BACKGROUND: Alzheimer's Disease (AD) is a progressive neurological disorder with no specific curative medications. While only a few medications are approved by FDA (i.e., donepezil, galantamine, rivastigmine, and memantine) to relieve symptoms (e.g., cognitive decline), sophisticated clinical skills are crucial to optimize the appropriate regimens given the multiple coexisting comorbidities in this patient population. OBJECTIVE: Here, we propose a study to leverage reinforcement learning (RL) to learn the clinicians' decisions for AD patients based on the longitude records from Electronic Health Records (EHR). METHODS: In this study, we withdraw 1,736 patients fulfilling our criteria, from the Alzheimer's Disease Neuroimaging Initiative(ADNI) database. We focused on the two most frequent concomitant diseases, depression, and hypertension, thus resulting in five main cohorts, 1) whole data, 2) AD-only, 3) AD-hypertension, 4) AD-depression, and 5) AD-hypertension-depression. We modeled the treatment learning into an RL problem by defining the three factors (i.e., states, action, and reward) in RL in multiple strategies, where a regression model and a decision tree are developed to generate states, six main medications extracted (i.e., no drugs, cholinesterase inhibitors, memantine, hypertension drugs, a combination of cholinesterase inhibitors and memantine, and supplements or other drugs) are for action, and Mini-Mental State Exam (MMSE) scores are for reward. RESULTS: Given the proper dataset, the RL model can generate an optimal policy (regimen plan) that outperforms the clinician's treatment regimen. With the smallest data samples, the optimal-policy (i.e., policy iteration and Q-learning) gained a lesser reward than the clinician's policy (mean -2.68 and -2.76 vs . -2.66, respectively), but it gained more reward once the data size increased (mean -3.56 and -2.48 vs . -3.57, respectively). CONCLUSIONS: Our results highlight the potential of using RL to generate the optimal treatment based on the patients' longitude records. Our work can lead the path toward the development of RL-based decision support systems which could facilitate the daily practice to manage Alzheimer's disease with comorbidities.
BACKGROUND: Alzheimer's disease (AD) is a progressive neurological disorder with no specific curative medications. Sophisticated clinical skills are crucial to optimize treatment regimens given the multiple coexisting comorbidities in the patient population. OBJECTIVE: Here, we propose a study to leverage reinforcement learning (RL) to learn the clinicians' decisions for AD patients based on the longitude data from electronic health records. METHODS: In this study, we selected 1736 patients from the Alzheimer's Disease Neuroimaging Initiative (ADNI) database. We focused on the two most frequent concomitant diseases-depression, and hypertension, thus creating 5 data cohorts (ie, Whole Data, AD, AD-Hypertension, AD-Depression, and AD-Depression-Hypertension). We modeled the treatment learning into an RL problem by defining states, actions, and rewards. We built a regression model and decision tree to generate multiple states, used six combinations of medications (ie, cholinesterase inhibitors, memantine, memantine-cholinesterase inhibitors, hypertension drugs, supplements, or no drugs) as actions, and Mini-Mental State Exam (MMSE) scores as rewards. RESULTS: Given the proper dataset, the RL model can generate an optimal policy (regimen plan) that outperforms the clinician's treatment regimen. Optimal policies (ie, policy iteration and Q-learning) had lower rewards than the clinician's policy (mean -3.03 and -2.93 vs. -2.93, respectively) for smaller datasets but had higher rewards for larger datasets (mean -4.68 and -2.82 vs. -4.57, respectively). CONCLUSIONS: Our results highlight the potential of using RL to generate the optimal treatment based on the patients' longitude records. Our work can lead the path towards developing RL-based decision support systems that could help manage AD with comorbidities.
Title: Soluble epoxide hydrolase deficiency promotes liver regeneration and ameliorates liver injury in mice by regulating angiocrine factors and angiogenesis Deng W, Hu T, Xiong W, Jiang X, Cao Y, Li Z, Jiang H, Wang X Ref: Biochimica & Biophysica Acta Gen Subj, :130394, 2023 : PubMed
BACKGROUND: Soluble epoxide hydrolase (sEH) is a key enzyme for the hydrolysis of epoxyeicosatrienoic acids (EETs) and has been implicated in the pathogenesis of hepatic inflammation, fibrosis, cancer, and nonalcoholic fatty liver disease. However, the role of sEH in liver regeneration and injury remains unclear. METHODS: This study used sEH-deficient (sEH(-/-)) mice and wild-type (WT) mice. Hepatocyte proliferation was assessed by immunohistochemical (IHC) staining for Ki67. Liver injury was evaluated by histological staining with hematoxylin and eosin (H&E), Masson's trichrome, and Sirius red, as well as IHC staining for alpha-SMA. Hepatic macrophage infiltration and angiogenesis were reflected by IHC staining for CD68 and CD31. Liver angiocrine levels were detected by ELISA. The mRNA levels of angiocrine or cell cycle-related genes were measured by quantitative real-time RT-PCR (qPCR). The protein levels of cell proliferation-related protein and phosphorylated signal transducer and activator of transcription 3 (STAT3) were detected by western blotting. RESULTS: sEH mRNA and protein levels were significantly upregulated in mice after 2/3 partial hepatectomy (PHx). Compared with WT mice, sEH(-/-) mice exhibited a higher liver/body weight ratio and more Ki67-positive cells on days 2 and 3 after PHx. The accelerated liver regeneration in sEH(-/-) mice was attributed to angiogenesis and endothelial-derived angiocrine (HGF) production. Subsequently, hepatic protein expression of cyclinD1 (CYCD1) and the downstream direct targets of the STAT3 pathway, such as c-fos, c-jun, and c-myc, were also suppressed post-PHx in sEH(-/-) compared to WT mice. Furthermore, sEH deficiency attenuated CCl(4)-induced acute liver injury and reduced fibrosis in both CCl(4) and bile duct ligation (BDL)-induced liver fibrosis rodent models. Compared with WT mice, sEH(-/-) mice had slightly decreased hepatic macrophage infiltration and angiogenesis. Meanwhile, sEH(-/-) BDL mice had more Ki67-positive cells in the liver than WT BDL mice. CONCLUSIONS: sEH deficiency alters the angiocrine profile of liver endothelial to accelerate hepatocyte proliferation and liver regeneration, and blunts acute liver injury and fibrosis by inhibiting inflammation and angiogenesis. sEH inhibition is a promising target for liver diseases to improve liver regeneration and damage.
Title: The cholinergic pathway transmits signals of neuropeptide F to regulate feeding of Ostrinia furnacalis larvae Jiang X, Shi J, Yang H, Zhao Z Ref: Pest Manag Sci, :, 2023 : PubMed
BACKGROUND: Feeding is the basis of animal survival and reproduction. In insects, the neuropeptide F (NPF), a homologous polypeptide of NPY in vertebrates, plays an important role in regulation of feeding behavior. However, relatively little has been known about the molecular mechanism of feeding. RESULTS: In this study, we show that the cholinergic pathway is very important in signaling transmission of NPF feeding regulation in Ostrinia furnacalis larvae, in which the choline acetyltransferase (ChAT), the vesicular acetylcholine transporter (vAChT) in presynaptic membrane and the nicotinic acetylcholine receptor (nAChR) in postsynaptic membrane are positively regulated by NPF, while the ace1 and ace2 encoding the acetylcholinesterase (AChE) are negatively regulated by NPF, leading to a balance of acetylcholine (ACh) - the excitatory transmitter. More, the cholinergic pathway further transmits signaling to the downstream pathways of the phosphoInositide-3 kinase (PI3K) and the cAMP responsive element binding protein (CREB), respectively. CONCLUSION: The cholinergic transmission, positively regulated by NPF, is involved in feeding of O. furnacalis larvae via downstream PI3K and the CREB pathways, respectively. The deexcitation of cell cholinergic pathway or inhibition of PI3K and CREB lead to decreases of larval feeding amount.
Epoxyeicosatrienoic acids (EETs) have pleiotropic endogenous cardiovascular protective effects and can be hydrolyzed to the corresponding dihydroxyeicosatrienoic acids by soluble epoxide hydrolase (sEH). Heart failure with preserved ejection fraction (HFpEF) has shown an increased prevalence and worse prognosis over the decades. However, the role of sEH activity in HFpEF remains unclear. We enrolled 500 patients with HFpEF and 500 healthy controls between February 2010 and March 2016. Eight types of sEH-related eicosanoids were measured according to target metabolomics, and their correlation with clinical endpoints was also analyzed. The primary endpoint was cardiac mortality, and the secondary endpoint was a composite of cardiac events, including heart failure (HF) readmission, cardiogenic hospitalization, and all-cause mortality. Furthermore, the effect of sEH inhibitors on cardiac diastolic function in HFpEF was investigated in vivo and in vitro. Patients with HFpEF showed significantly enhanced EET degradation by the sEH enzyme compared with healthy controls. More importantly, sEH activity was positively correlated with cardiac mortality in patients with HFpEF, especially in older patients with arrhythmia. A consistent result was obtained in the multiple adjusted models. Decreased sEH activity by the sEH inhibitor showed a significant effective effect on the improvement of cardiac diastolic function by ameliorating lipid disorders in cardiomyocytes of HFpEF mouse model. This study demonstrated that increased sEH activity was associated with cardiac mortality in patients with HFpEF and suggested that sEH inhibition could be a promising therapeutic strategy to improve diastolic cardiac function. Clinical trial identifier: NCT03461107 (https://clinicaltrials.gov). SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s43657-022-00069-8.
Millions of individuals globally suffer from inadvertent, occupational or self-harm exposures from organophosphate (OP) insecticide exposures; significantly impacting human health. Similar to nerve agents, insecticides are neurotoxins which target and inhibit acetylcholinesterase (AChE) in central and peripheral synapses in the cholinergic nervous system. Post-exposure therapeutic countermeasures generally include admin-istration of atropine with an oxime, to reactivate the OP-inhibited AChE. However, animal model studies and recent clinical trials using insecticide-poisoned individuals have shown minimal clinical benefits of the currently approved oximes and their efficacy as antidotes has been debated. Currently-used oximes either reactivate poorly, do not readily cross the blood brain barrier (BBB), or are rapidly cleared from the circulation and must be repeatedly administered. Zwitterionic oximes of unbranched and simplified structure eg RS194B have been developed that efficiently cross the BBB resulting in reactivation of OP-inhibited AChE and dramatic reversal of severe clinical symptoms in mice and macaques exposed to OP insecticide or nerve agents. Thus, a single IM injection of RS194B has been shown to rapidly restore blood AChE and butyrylcholinesterase (BChE) activity, reverse cholinergic symptoms and prevent death in macaques following lethal inhaled sarin and paraoxon exposure. The present macaque studies extend these studies and assess the ability of post-exposure RS194B treatment to counteract oral poisoning by highly toxic diethylphosphorothioate insecticides such as parathion and chlorpyrifos, which require oxidation by P450 in the liver to convert inactive thions to the active toxic oxon forms, and once again demonstrated its efficacy to reactivate and alleviate clinical symptoms within 60 mins of a single IM administration. Furthermore, when delivered orally, the Tmax of RS194B at 1-2 hours was in the same range as those administered IM but were maintained in the circulation for longer periods greatly facilitating the use of RS194B as a non-invasive treatment, especially in isolated rural settings.
The aerial crop dusting and spraying of fields with the phosphorothioate insecticide parathion in the late 1900s, significantly improved crop yields but resulted in high levels of occupational toxicity in handlers and agricultural workers, as well as cases of intentional self-harm poisoning, culminating in its banning in many western countries by early 2000s. However because of the low solubility and volatility of parathion, most available products were formulated using organic solvents e.g. xylene, to increase the efficacy of the aerosols, dusts. In the present study, the toxicity of parathion was assessed when formulated in aqueous solvents (ethanol/PBS (1:9), and delivered to macaques as an aerosol. Doses of 800 microg/kg and 1.6 mg/kg were delivered one day apart, using a modified nebulizer calculated to result in lung deposition of -380 microg/kg with a similar or larger amount being swallowed; these doses being similar to the estimated lethal oral dose 286ug/kg - 1.43 mg/kg of formulated parathion in humans. Surprisingly, this dose (a combined amount of -14 mg) caused only low AChE inhibition and moderate BChE inhibition with no clinical symptoms, indicating that the use of organic solvents may have previously played a critical role in the severity of parathion toxicity following inhalation exposure. In addition, unlike constitutively toxic OPs, which are highly toxic when inhaled, these results are consistent with the idea that phosphorothioate insecticides, appear to be more intoxicating following oral than inhalation exposure. However, this still remains uncertain because the presence of organic solvents in the ingested parathion studies was not always known.
Title: Synergism of Feeding and Digestion Regulated by the Neuropeptide F System in Ostrinia furnacalis Larvae Zhao J, Song Y, Jiang X, He L, Wei L, Zhao Z Ref: Cells, 12:, 2023 : PubMed
Feeding is crucial for the growth and survival of animals, including humans, but relatively little is known about how it is regulated. Here, we show that larval feeding in Ostrinia furnacalis is regulated by neuropeptide F (NPF, the homologous peptide of mammalian NPY) via the insulin signalling pathway in the midgut. Furthermore, the genes pi3k and mtor in the insulin pathway positively regulate alpha-amylase and lipase of the midgut by recruiting the transcription factors c-Myc and PPARgamma for binding to the promotors of these two enzymes. Importantly, we find that the feeding behaviour and the digestive system of midgut in O. furnacalis larvae are closely related and interactive in that knocking down alpha-amylase or lipase induces a reduction in larval feeding, while food-deprived larvae lead to fewer expressions of alpha-amylase and lipase. Importantly, it is the gut NPF that regulates the alpha-amylase and lipase, while variations of alpha-amylase and lipase may feed back to the brain NPF. This current study reveals a molecular feedback mechanism between feeding behaviour and the digestive system that is regulated by the conserved NPF via insulin signalling systems in the midgut of O. furnacalis larvae.
Plant tannases (TAs) or tannin acyl hydrolases, a class of recently reported carboxylesterase (CXE) in tannin-rich plants, are involved in the degalloylation of two important secondary metabolites: flavan-3-ol gallates and hydrolyzable tannins (HTs). In this paper, we have made a new progress on the function of Camellia sinensis (Cs) TA-it is a hydrolase with promiscuous acyltransferase activity in vitro and in vivo experiments and promotes the synthesis of simple galloyl glucoses and flavan-3-ols gallates in plants. We gained the new understanding to the functions of CsTA through enzyme analysis, protein mass spectrometry identification, metabolic analysis of plants by genetic modification. Firstly, CsTA was proved that it is not only a hydrolase but also an acyltransferase. In the two-step covalent catalytic reaction, when CsTA hydrolyzes the galloylated compounds epigallocatechin-3-gallate (EGCG) or 1,2,3,4,6-penta-O-galloyl-beta-D-glucose (PGG) into their degalloylated forms, a long-lived Ser159-linked galloyl-enzyme covalent intermediate is also formed. Under nucleophilic attack, the galloyl group on the intermediate is transferred to the nucleophilic acyl acceptors (including water, methanol, flavan-3-ols and simple galloyl glucoses). Then, metabolic analysis suggested that transiently overexpression of TAs in young strawberry fruits, young leaves of tea plants and young leaves of Chinese bayberry actually increased the total content of simple galloyl glucoses and flavan-3-ol gallates. Overall, these findings provide new insights into the promiscuous acyltransferase activity of plant tannase.
Title: Major biotransformation of phthalic acid esters in Eisenia fetida: Mechanistic insights and association with catalytic enzymes and intestinal symbionts Fan X, Gu C, Jin Z, Cai J, Bian Y, Wang F, Chen H, Jiang X Ref: Environ Int, 171:107712, 2022 : PubMed
Phthalic acid esters (PAEs) are an important group of organic pollutants that are widely used as plasticizers in the environment. The PAEs in soil organisms are likely to be biotransformed into a variety of metabolites, and the combined toxicity of PAEs and their metabolites might be more serious than PAEs alone. However, there are only a few studies on PAE biotransformation by terrestrial animals, e.g. earthworms. Herein, the key biotransformation pathways of PAEs and their association with catalytic enzymes and intestinal symbionts in earthworms were studied using in vivo and in vitro incubation approaches. The widely distributed PAE in soil, dibutyl phthalate (DBP), was proven to be biotransformed rapidly together with apparent bioaccumulation in earthworms. The biotransformation of PAE congeners with medium or long side chains appeared to be faster compared with those with short side chains. DBP was biotransformed into butyl methyl phthalate (BMP), monobutyl phthalate (MBP), and phthalic acid (PA) through esterolysis and transesterification. Besides, the generation of small quantities of low-molecular weight metabolites via beta-oxidation, decarboxylation or ring-cleavage, was also observed, especially when the appropriate proportion of NADPH coenzyme was applied to transfer electrons for oxidases. Interestingly, the esterolysis of PAEs was mainly regulated by the cytoplasmic carboxylesterase (CarE) in earthworms, with a Michaelis constant (K(m)) of 0.416smM in the catalysis of DBP. The stronger esterolysis in non-intestinal tissues indicated that the CarE was primarily secreted by non-intestinal tissues of earthworms. Additionally, the intestinal symbiotic bacteria of earthworms could respond to PAE stress, leading to the changes in their diversity and composition. The enrichment of some genera e.g. Bacillus and Paracoccus, and the enhancement of metabolism function, e.g. amino acids, energy, lipids biosynthesis and oxidase secretion, indicated their important role in the degradation of PAEs.
Title: Identification of Differential Expression Genes between Volume and Pressure Overloaded Hearts Based on Bioinformatics Analysis Fu Y, Zhao D, Zhou Y, Lu J, Kang L, Jiang X, Xu R, Ding Z, Zou Y Ref: Genes (Basel), 13:, 2022 : PubMed
Volume overload (VO) and pressure overload (PO) are two common pathophysiological conditions associated with cardiac disease. VO, in particular, often occurs in a number of diseases, and no clinically meaningful molecular marker has yet been established. We intend to find the main differential gene expression using bioinformatics analysis. GSE97363 and GSE52796 are the two gene expression array datasets related with VO and PO, respectively. The LIMMA algorithm was used to identify differentially expressed genes (DEGs) of VO and PO. The DEGs were divided into three groups and subjected to functional enrichment analysis, which comprised GO analysis, KEGG analysis, and the protein-protein interaction (PPI) network. To validate the sequencing data, cardiomyocytes from AR and TAC mouse models were used to extract RNA for qRT-PCR. The three genes with random absolute values of LogFC and indicators of heart failure (natriuretic peptide B, NPPB) were detected: carboxylesterase 1D (CES1D), whirlin (WHRN), and WNK lysine deficient protein kinase 2 (WNK2). The DEGs in VO and PO were determined to be 2761 and 1093, respectively, in this study. Following the intersection, 305 genes were obtained, 255 of which expressed the opposing regulation and 50 of which expressed the same regulation. According to the GO and pathway enrichment studies, DEGs with opposing regulation are mostly common in fatty acid degradation, propanoate metabolism, and other signaling pathways. Finally, we used Cytoscape's three techniques to identify six hub genes by intersecting 255 with the opposite expression and constructing a PPI network. Peroxisome proliferator-activated receptor (PPARalpha), acyl-CoA dehydrogenase medium chain (ACADM), patatin-like phospholipase domain containing 2 (PNPLA2), isocitrate dehydrogenase 3 (IDH3), heat shock protein family D member 1 (HSPD1), and dihydrolipoamide S-acetyltransferase (DLAT) were identified as six potential genes. Furthermore, we predict that the hub genes PPARalpha, ACADM, and PNPLA2 regulate VO myocardial changes via fatty acid metabolism and acyl-Coa dehydrogenase activity, and that these genes could be employed as basic biomarkers for VO diagnosis and treatment.
BACKGROUND: Glimepiride has good cardiovascular safety. However, whether glimepiride benefits clinical cardiovascular outcomes is unclear. METHODS: A total of 21,451 inpatients with type 2 diabetes (T2D) and chronic heart failure (CHF) were analyzed, including 638 who received glimepiride treatment and 20,813 who did not. Propensity score matching yielded 509 pairs (glimepiride and non-glimepiride groups), and both groups were followed up. Kaplan-Meier and Cox regression analyses were used to compare all-cause mortality, cardiovascular mortality, hospitalizations and emergency visits for heart failure, and hospitalizations for acute myocardial infarction or stroke. RESULTS: During follow-up, the all-cause mortality (adjusted hazard ratio [HR], 0.47; 95% confidence interval [CI], 0.35-0.63; P < 0.001), cardiovascular mortality (adjusted HR, 0.34; 95% CI, 0.24-0.48; P < 0.001), and number of hospitalizations and emergency visits for heart failure (adjusted HR, 0.42; 95% CI, 0.36-0.50; P < 0.001) and hospitalizations for acute myocardial infarction or stroke (adjusted HR, 0.53; 95% CI, 0.38-0.73; P < 0.001) were significantly lower in the glimepiride group; the conclusion remained similar in all subgroups. Furthermore, high-dose glimepiride use (2-4mg/day) was associated with lower cardiovascular mortality than low-dose (1mg/day) (adjusted HR, 0.55; 95% CI, 0.31-0.99; P = 0.047). Glimepiride exhibited good molecular docking with soluble epoxide hydrolase (sEH) and increased the level epoxyeicosatrienoic acid (EET). CONCLUSIONS: Long-term continuous glimepiride use is associated with better survival, fewer hospitalizations and emergency visits for heart failure, and fewer hospitalizations for acute myocardial infarction or stroke in patients with T2D and CHF. High-dose glimepiride has greater cardiovascular protective advantages than low-dose glimepiride. The cardiovascular protective effect of glimepiride may be related to the EET level increase through sEH inhibition.
BACKGROUND: A critical and controversial issue is whether antiviral therapy should be recommended in chronic hepatitis B virus (HBV) infection patients with persistently normal alanine aminotransferase (PNALT) and detectable HBV DNA. The study aimed to develop a non-invasive model for predicting significant liver histological changes (SLHC), which is the histological indication for antiviral therapy in chronic hepatitis B (CHB) patients with PNALT and detectable HBV DNA. METHODS: 398 chronic HBV infection patients with PNALT and detectable HBV DNA who underwent liver biopsy were divided into the estimation set (n = 256) and validation set (n = 142). A multivariate logistic regression model was developed to predict SLHC in the estimation set, and the diagnostic performance was further validated in the validation set. RESULTS: 132 patients (33.2%) with PNALT and detectable HBV DNA had SLHC. Aspartate aminotransferase (AST), cholinesterase (ChE), and liver stiffness measurement (LSM) were identified as the independent predictors of SLHC. The AUROC of the SLHC index, which combined AST, ChE, and LSM, was 0.824 and 0.816 in the estimation and validation set, respectively, for the prediction of SLHC. Applying the SLHC index >= 0.15, the presence of SLHC could be excluded with high negative predictive value in the estimation set (93.2%) and in the validation set (90.2%). Applying the SLHC index <= 0.55, the presence of SLHC could be considered with high positive predictive value in the estimation set (79.2%) and in the validation set (76.5%). CONCLUSION: The SLHC index provides a high accuracy in predicting liver histological indication for antiviral therapy in CHB patients with PNALT and detectable HBV DNA.
Title: Two-Stage SN38 Release from a Core-Shell Nanoparticle Enhances Tumor Deposition and Antitumor Efficacy for Synergistic Combination with Immune Checkpoint Blockade Jiang X, Lee M, Xia J, Luo T, Liu J, Rodriguez M, Lin W Ref: ACS Nano, :, 2022 : PubMed
Long-circulating nanomedicines efficiently deliver chemotherapies to tumors to reduce general toxicity. However, extended blood circulation of nanomedicines can increase drug exposure to leukocytes and lead to hematological toxicity. Here, we report a two-stage release strategy to enhance the drug deposition and antitumor efficacy of OxPt/SN38 core-shell nanoparticles with a hydrophilic oxaliplatin (OxPt) prodrug coordination polymer core and a lipid shell containing a hydrophobic cholesterol-conjugated SN38 prodrug (Chol-SN38). By conjugating cholesterol to the phenol group of SN38 via an acetal linkage and protecting the 20-hydroxy position with a trimethylsilyl (TMS) group, Chol-SN38 releases SN38 in two stages via esterase-catalyzed cleavage of the acetal linkage in the liver followed by acid-mediated hydrolysis of the TMS group to preferentially release SN38 in tumors. Compared to irinotecan, OxPt/SN38 reduces SN38 blood exposure by 9.0 times and increases SN38 tumor exposure by 4.7 times. As a result, OxPt/SN38 inhibits tumor growth on subcutaneous, spontaneous, and metastatic tumor models by causing apoptotic and immunogenic cell death. OxPt/SN38 exhibits strong synergy with the immune checkpoint blockade to regress subcutaneous colorectal and pancreatic tumors with 33-50% cure rates and greatly inhibits tumor growth and invasion in a spontaneous prostate cancer model and a liver metastasis model of colorectal cancer without causing side effects. Mechanistic studies revealed important roles of enhanced immunogenic cell death and upregulated PD-L1 expression by OxPt/SN38 in activating the tumor immune microenvironment to elicit potent antitumor immunity. This work highlights the potential of combining innovative prodrug design and nanomedicine formulation to address unmet needs in cancer therapy.
Title: Evodiamine-A Privileged Structure with Broad-Ranging Biological Activities Li D, Li Y, Jiang X, Liu W, Zhao Q Ref: Mini Rev Med Chem, :, 2022 : PubMed
Evodiamine (EVO) is a natural quinolone alkaloid firstly isolated from the fruit of Evodia rutaecarpa, which is one of the most frequently used traditional Chinese herb for treating a variety of ailments including headaches, abdominal pain, vomiting, diarrhea, amenorrhea difficult menstruation, postpartum hemorrhage, and other diseases. Latest pharmacological studies showed that EVO possesses a broad spectrum of pharmacological activities through different mechanisms. However, its moderate activities and poor physicochemical properties hampered its clinical application. In this regard, the modification of EVO aiming at seeking derivatives with more potency and better physicochemical properties has been extensively emerging. These derivatives exhibit diverse biological activities including antitumor, anti-Alzheimer's disease, anti-pulmonary hypertension, anti-fungi, and thermogenic activities via a variety of mechanisms. Moreover, they were described to act as single, dual, or multiple inhibitors or agonists of many proteins such as topoisomerase I, topoisomerase II, tubulin, histone deacetylase, sirtuins, butyrylcholinesterase, phosphodiesterase 5, and transient receptor potential vanilloid 1. However, hitherto, there is no comprehensive review to systematically summarize the derivatives of EVO. In this perspective, this paper aims to provide a comprehensive description of them focused on their diverse biological activities. For each biological activity, the mechanisms and the main structure-activity relationships (SARs) will be presented in cases where adequate information is available. Finally, future directions of this class of compounds will be discussed. This review will be helpful in understanding and encouraging further exploration of EVO.
Tacrine was the first approved drug by the FDA for the treatment of Alzheimer's disease (AD) but was withdrawn from the market due to its dose-dependent hepatotoxicity. Herein, we describe our efforts toward the discovery of a novel series of tacrine derivatives for cancer therapeutics. Intensive structural modifications of tacrine led to the identification of N-(4-{9-[(3S)-3-aminopyrrolidin-1-yl]-5,6,7,8-tetrahydroacridin-2-yl}pyridin-2-yl)cyclopropanecarboxamide hydrochloride ((S)-45, ZLWT-37) as a potent antiproliferative agent (GI(50) = 0.029 microM for HCT116). In addition, ZLWT-37 exhibited lower inhibitory activity against acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) compared to tacrine. The in vitro studies demonstrated that ZLWT-37 could significantly induce apoptosis and arrest the cell cycle in the G2/M phase in HCT116 cells. The in vivo studies revealed that compound ZLWT-37 showed excellent antitumor efficacy in HCT116 xenograft tumor model and favorable pharmacokinetics profiles (F% = 28.70%) as well as low toxicity in the acute toxicity test with a median lethal dose (LD(50)) of 380.3 mg/kg. Encouragingly, ZLWT-37 had no obvious hepatotoxicity, nephrotoxicity, and hematologic toxicity. Kinase assay suggested that ZLWT-37 possessed potent cyclin-dependent kinase 9 (CDK9) inhibitory activity (IC(50) = 0.002 microM) and good selectivity over CDK2 (IC(50) = 0.054 microM). Collectively, these findings indicate that compound ZLWT-37 is a promising anti-cancer agent that deserves further preclinical evaluation.
Multi-targeted directed ligands (MTDLs) are emerging as promising Alzheimer's disease (AD) therapeutic possibilities. Coumarin is a multifunctional backbone with extensive bioactivity that has been utilized to develop innovative anti-neurodegenerative properties and is a desirable starting point for the construction of MTDLs. Herein, we explored and synthesized a series of novel coumarin derivatives and assessed their inhibitory effects on cholinesterase (AChE, BuChE), GSK-3beta, and BACE1. Among these compounds, compound 30 displayed the multifunctional profile of targeting the AChE (IC(50) = 1.313 +/- 0.099 microM) with a good selectivity over BuChE (SI = 24.623), GSK-3beta (19.30% inhibition at 20 microM), BACE1 (IC(50) = 1.227 +/- 0.112 microM), along with moderate HepG2 cytotoxicity, SH-SY5Y cytotoxicity, low HL-7702 cytotoxicity, as well as good blood-brain barrier (BBB) permeability. Kinetic and docking studies indicated that compound 30 was a competitive AChE inhibitor. Furthermore, acute toxicity experiments revealed that it was non-toxic at a dosage of 1000 mg/kg. The ADME prediction results indicate that 30 has acceptable physicochemical properties. Collectively, these findings demonstrated that compound 30 would be a potential multifunctional candidate for AD therapy.
Alzheimer's disease (AD) is characterized by progressive cognitive impairment and mental behavior. The combination inhibition of two essential AD targets, acetylcholinesterase (AChE) and glycogen synthase kinase-3beta (GSK-3beta), might be a breakthrough in the discovery of therapeutic success. Herein, 17 beta-carboline-1,2,3-triazole hybrids were designed, synthesized, and evaluated for their AChE and GSK-3beta inhibitory potential. The results indicated that compound 21 has the most potent inhibition against eeAChE (IC(50) = 0.20 +/- 0.02 microM), hAChE (IC(50) = 0.34 +/- 0.01 microM) and GSK-3beta (IC(50) = 1.14 +/- 0.05 microM) among these compounds. In addition, it inhibited hAChE in a mixed type manner and could occupy the binding pocket forming diverse interactions with the target of AChE and GSK-3beta. Moreover, compound 21 showed low cytotoxicity against SH-SY5Y and HepG2 cell lines and good BBB permeability. Compound 21 also attenuated the tau hyperphosphorylation in the Tau (P301L) 293T cell model. The ADME projection exhibited that compound 21 has acceptable physicochemical characteristics. This study provides new leads for the assessment of AChE and GSK-3beta dual inhibition as a promising strategy for AD treatment.
Title: Oxidative stress and detoxification mechanisms of earthworms (Eisenia fetida) after exposure to flupyradifurone in a soil-earthworm system Qiao Z, Li P, Tan J, Peng C, Zhang F, Zhang W, Jiang X Ref: J Environ Manage, 322:115989, 2022 : PubMed
Flupyradifurone (FLU) has great application potential in agricultural production as a new generation of neonicotinoid insecticide after imidacloprid. Nevertheless, the toxic effects of FLU on non-target soil organisms remain unclear, resulting in considerable environmental risks. We evaluated the acute and subchronic toxicities of FLU to earthworms. The results of acute toxicity show that the median lethal concentration (LC(50)) values (14 d) of FLU were 186.9773 mg kg(-1) for adult earthworms and 157.6502 mg kg(-1) for juveniles, respectively. The subchronic toxicity of FLU that focused on the activities of antioxidant and detoxication enzymes showed the superoxide dismutase (SOD), catalase (CAT), and glutathione-S transferase (GST) activities in earthworms increased while the peroxidase (POD) and acetylcholinesterase (AChE) activities decreased after exposure to FLU. Oxidative damage analyses revealed that the reactive oxygen species (ROS) level and malonaldehyde (MDA) content in earthworms were increased by FLU, resulting in DNA damage. Transcriptomics and RT-qPCR confirmed that FLU influenced the expression of genes related to antioxidant response and detoxification of earthworms. Ultimately detoxification metabolism, environmental information processing, cell processes, and immune system pathways are significantly enriched to respond jointly to FLU. Our study fills the gaps in the toxicity of FLU to earthworms, providing a basis for its risk assessment of soil ecosystems and non-target biological toxicity.
Serine carboxypeptidase-like acyltransferases (SCPL-ATs) play a vital role in the diversification of plant metabolites. Galloylated flavan-3-ols highly accumulate in tea (Camellia sinensis), grape (Vitis vinifera), and persimmon (Diospyros kaki). To date, the biosynthetic mechanism of these compounds remains unknown. Herein, we report that two SCPL-AT paralogs are involved in galloylation of flavan-3-ols: CsSCPL4, which contains the conserved catalytic triad S-D-H, and CsSCPL5, which has the alternative triad T-D-Y. Integrated data from transgenic plants, recombinant enzymes, and gene mutations showed that CsSCPL4 is a catalytic acyltransferase, while CsSCPL5 is a non-catalytic companion paralog (NCCP). Co-expression of CsSCPL4 and CsSCPL5 is likely responsible for the galloylation. Furthermore, pull-down and co-immunoprecipitation assays showed that CsSCPL4 and CsSCPL5 interact, increasing protein stability and promoting post-translational processing. Moreover, phylogenetic analyses revealed that their homologs co-exist in galloylated flavan-3-ol- or hydrolyzable tannin-rich plant species. Enzymatic assays further revealed the necessity of co-expression of those homologs for acyltransferase activity. Evolution analysis revealed that the mutations of the CsSCPL5 catalytic residues may have taken place about 10 million years ago. These findings show that the co-expression of SCPL-ATs and their NCCPs contributes to the acylation of flavan-3-ols in the plant kingdom.
Activated autophagy-lysosomal pathway (ALP) can degrade virtually all kinds of cellular components, including intracellular lipid droplets, especially during catabolic conditions. Sustained lipolysis and increased plasma fatty acids concentrations are characteristic of dairy cows with hyperketonemia. However, the status of ALP in adipose tissue during this physiological condition is not well known. The present study aimed to ascertain whether lipolysis is associated with activation of ALP in adipose tissues of dairy cows with hyperketonemia and in calf adipocytes. In vivo, blood and subcutaneous adipose tissue (SAT) biopsies were collected from nonhyperketonemic (nonHYK) cows [blood beta-hydroxybutyrate (BHB) concentration <1.2 mM, n = 10] and hyperketonemic (HYK) cows (blood BHB concentration 1.2-3.0 mM, n = 10) with similar days in milk (range: 3-9) and parity (range: 2-4). In vitro, calf adipocytes isolated from 5 healthy Holstein calves (1 d old, female, 30-40 kg) were differentiated and used for (1) treatment with lipolysis inducer isoproterenol (ISO, 10 microM, 3 h) or mammalian target of rapamycin inhibitor Torin1 (250 nM, 3 h), and (2) pretreatment with or without the ALP inhibitor leupeptin (10 microg/mL, 4 h) followed by ISO (10 microM, 3 h) treatment. Compared with nonHYK cows, serum concentration of free fatty acids was greater and serum glucose concentration, DMI, and milk yield were lower in HYK cows. In SAT of HYK cows, ratio of phosphorylated hormone-sensitive lipase to hormone-sensitive lipase, and protein abundance of adipose triacylglycerol lipase were greater, but protein abundance of perilipin 1 (PLIN1) and cell death-inducing DNA fragmentation factor-alpha-like effector c (CIDEC) was lower. In addition, mRNA abundance of autophagy-related 5 (ATG5), autophagy-related 7 (ATG7), and microtubule-associated protein 1 light chain 3 beta (MAP1LC3B), protein abundance of lysosome-associated membrane protein 1, and cathepsin D, and activity of beta-N-acetylglucosaminidase were greater, whereas protein abundance of sequestosome-1 (p62) was lower in SAT of HYK cows. In calf adipocytes, treatment with ISO or Torin1 decreased protein abundance of PLIN1, and CIDEC, and triacylglycerol content in calf adipocytes, but increased glycerol content in the supernatant of calf adipocytes. Moreover, the mRNA abundance of ATG5, ATG7, and MAP1LC3B was upregulated, the protein abundance of lysosome-associated membrane protein 1, cathepsin D, and activity of beta-N-acetylglucosaminidase were increased, whereas the protein abundance of p62 was decreased in calf adipocytes treated with ISO or Torin1 compared with control group. Compared with treatment with ISO alone, the protein abundance of p62, PLIN1, and CIDEC, and triacylglycerol content in calf adipocytes were higher, but the glycerol content in the supernatant of calf adipocytes was lower in ISO and leupeptin co-treated group. Overall, these data indicated that activated ALP is associated with increased lipolysis in adipose tissues of dairy cows with hyperketonemia and in calf adipocytes.
Title: Transcriptomic Identification and Expression Profile Analysis of Odorant-Degrading Enzymes from the Asian Corn Borer Moth, Ostrinia furnacalis Zhang L, Shen Y, Jiang X, Liu S Ref: Insects, 13:, 2022 : PubMed
The Asian corn borer moth Ostrinia furnacalis is an important lepidopteran pest of maize in Asia. Odorant-degrading enzymes (ODEs), including carboxylesterases (CCEs), glutathione S-transferases (GSTs), cytochrome P450s (CYPs), UDP-glycosyltransferases (UGTs), and aldehyde oxidases (AOXs), are responsible for rapid inactivation of odorant signals in the insect antennae. In this study, we performed a transcriptome assembly for the antennae of O. furnacalis to identify putative ODE genes. Transcriptome sequencing revealed 35,056 unigenes, and 21,012 (59.94%) of these were annotated by searching against the reference sequences in the NCBI non-redundant (NR) protein database. For functional classification, these unigenes were subjected to Gene Ontology (GO), Eukaryotic Orthologous Groups (KOG), and Kyoto Encyclopedia of Genes and Genomes (KEGG) annotations. We identified 79 genes encoding putative ODEs: 19 CCEs, 17 GSTs, 24 CYPs, 13 UGTs, and 6 AOXs. BLASTX best hit results indicated that these genes shared quite high amino acid identities with their respective orthologs from other lepidopteran species. Reverse transcription-quantitative PCR showed that OfurCCE2, OfurCCE5, and OfurCCE18 were enriched in male antennae, while OfurCCE7 and OfurCCE10 were enriched in female antennae. OfurCCE14 and OfurCCE15 were expressed at near-equal amounts in the antennae of both sexes. Our findings establish a solid foundation for future studies aimed at understanding the olfactory functions of these genes in O. furnacalis.
Title: The Functional Characterization of Carboxylesterases Involved in the Degradation of Volatile Esters Produced in Strawberry Fruits Zhang L, Zhou K, Wang M, Li R, Dai X, Liu Y, Jiang X, Xia T, Gao L Ref: Int J Mol Sci, 24:383, 2022 : PubMed
Volatile ester compounds are important contributors to the flavor of strawberry, which affect consumer preference. Here, the GC-MS results showed that volatile esters are the basic aroma components of strawberry, banana, apple, pear, and peach, and the volatile esters were significantly accumulated with the maturation of strawberry fruits. The main purpose of this study is to discuss the relationship between carboxylesterases (CXEs) and the accumulation of volatile ester components in strawberries. FaCXE2 and FaCXE3 were found to have the activity of hydrolyzing hexyl acetate, Z-3-hexenyl acetate, and E-2-hexenyl acetate to the corresponding alcohols. The enzyme kinetics results showed that FaCXE3 had the higher affinity for hexyl acetate, E-2-hexenyl acetate, and Z-3-hexenyl acetate compared with FaCXE2. The volatile esters were mainly accumulated at the maturity stages in strawberry fruits, less at the early stages, and the least during the following maturation stages. The expression of FaCXE2 gradually increased with fruit ripening and the expression level of FaCXE3 showed a decreasing trend, which suggested the complexity of the true function of CXEs. The transient expression of FaCXE2 and FaCXE3 genes in strawberry fruits resulted in a significantly decreased content of volatile esters, such as Z-3-hexenyl acetate, methyl hexanoate, methyl butyrate, and other volatile esters. Taken together, FaCXE2 and FaCXE3 are indeed involved in the regulation of the synthesis and degradation of strawberry volatile esters.
Title: Mechanistic insights into primary biotransformation of diethyl phthalate in earthworm and significant SOD inhibitory effect of esterolytic products Fan X, Gu C, Cai J, Zhong M, Bian Y, Jiang X Ref: Chemosphere, 288:132491, 2021 : PubMed
Phthalic acid esters (PAEs) are used as plasticizer or modifier in artificially-manufactured products. Though the rapid biotransformation of phthalates in microbes and plants have been well documented, it is less studied yet in terrestrial animals, e.g. earthworm. In this study, the major biotransformation of diethyl phthalate (DEP) in Eisenia fetida was illustrated using in vitro incubation of earthworm crude enzymes. DEP could be substantially biotransformed into phthalate monoester (MEP) and a small amount of phthalic acid (PA) through esterolysis, which was verified to be driven by endogenous carboxylesterase. Despite the inferior contribution, the oxidation of DEP might also occur under the initiated electron transfer by NADPH coenzyme. The dominant metabolite MEP showed a higher inhibition of superoxide dismutase (SOD) activity than DEP with EC(50) of 0.0082 +/- 0.0016 mmol/L, so the higher ecological risks of MEP would be marked. The inhibition effect of PA was validated to be even stronger than MEP though it was slightly generated. The direct binding interaction with SOD was proved to be an important molecular event for regulation of SOD activity. Besides the static quenching mechanism, the caused conformational changes including despiralization of alpha-helix and spatial reorientation of tryptophan were spectrally believed to affect binding and underlie inhibition efficiency of SOD activity.
Title: Two cases of Chanarin-Dorfman syndrome with novel and recurrent mutations in the ABHD5 gene Jiang X, Zhong W, Yu B, Lin Z, Wang H Ref: Int J Dermatol, :, 2021 : PubMed
Title: Discovery of 2-(cyclopropanecarboxamido)-N-(5-((1-(4-fluorobenzyl)piperidin-4-yl)methoxy)pyridin-3-yl)isonicotinamide as a potent dual AChE/GSK3beta inhibitor for the treatment of Alzheimer's disease: Significantly increasing the level of acetylcholine in the brain without affecting that in intestine Jiang X, Liu C, Zou M, Xie H, Lin T, Lyu W, Xu J, Li Y, Feng F and Liu W<1 more author(s)>Jiang X, Liu C, Zou M, Xie H, Lin T, Lyu W, Xu J, Li Y, Feng F, Sun H, Liu W (- 1) Ref: Eur Journal of Medicinal Chemistry, 223:113663, 2021 : PubMed
Acetylcholinesterase (AChE) inhibitors are currently the first-line drugs approved by the FDA for the treatment of Alzheimer's disease (AD). However, a short effective-window limits their therapeutic benefits. Clinical studies have confirmed that the combination of AChE inhibitors and neuroprotective agents exhibits better anti-AD effects. We have previously reported that the dual AChE/GSK3beta (Glycogen synthase kinase 3beta) modulators have both neuroprotective effects and cognitive impairment-improvement effects. In this study, we characterized a new backbone of the AChE/GSK3beta inhibitor 11c. It was identified as a highly potent AChE inhibitor and was found superior to donepezil, the first-line drug for the treatment of AD. In vivo studies confirmed that 11c significantly inhibited the activity of AChE in the brain but had little effect on the activity of AChE in the intestine. This advantage of 11c was expected to reduce the peripheral side effects caused by donepezil. Furthermore, biomarker studies have shown that 11c also improved the levels of acetylcholine and synaptophysin in the brain and exhibited neuroprotective effects. Preliminary in vivo and in vitro research results underline the exciting potential of compound 11c in the treatment of AD.
Cannabidiol (CBD) and rivastigmine have been launched as drugs for treating dementia and cholinesterases (ChEs) are ideal drug targets. This study focused on developing novel ChE inhibitors as drug leads against dementia through molecular modeling and fragment reassembly approaches. A potent carbamate fragment binding to active site gorge of BuChE was found via a docking-based structural splicing approach, thus, 17 novel compounds were designed by structural reassembly. Compound C16 was identified as a highly selective potent BuChE inhibitor (IC(50) = 5.3 nM, SI > 4000), superior to CBD (IC(50) = 0.67 microM). C16 possessed BBB penetrating ability, benign safety, neuroprotection, antioxidant and pseudo-irreversible BuChE inhibition (K(d) = 13 nM, k(2) = 0.26 min(-1)), showing good drug-like properties. In vivo studies confirmed that C16 significantly ameliorated the scopolamine-induced cognition impairment, almost entirely recovered the Abeta(1-42) (icv)-impaired cognitive function to the normal level, showed better behavioral performance than donepezil and good anti-amyloidogenic effect. Hence, the potential BuChE inhibitor C16 can be developed as a promising disease-modifying treatment of AD.
The natural product harmine, a representative beta-carboline alkaloid from the seeds of Peganum harmala L. (Zygophyllaceae), possesses a broad spectrum of biological activities. In this study, a novel series of harmine derivatives containing N-benzylpiperidine moiety were identified for the treatment of Alzheimer's disease (AD). The results showed that all the derivatives possessed significant anti-acetylcholinesterase (AChE) activity and good selectivity over butyrylcholinesterase (BChE). In particular, compound ZLWH-23 exhibited potent anti-AChE activity (IC(50) = 0.27 microM) and selective BChE inhibition (IC(50) = 20.82 microM), as well as acceptable glycogen synthase kinase-3 (GSK-3beta) inhibition (IC(50) = 6.78 microM). Molecular docking studies and molecular dynamics simulations indicated that ZLWH-23 could form stable interaction with AChE and GSK-3beta. Gratifyingly, ZLWH-23 exhibited good selectivity for GSK-3beta over multi-kinases and very low cytotoxicity towards SH-SY5Y, HEK-293T, HL-7702, and HepG2 cell lines. Importantly, ZLWH-23 displayed efficient reduction against tau hyperphosphorylation on Ser-396 site in Tau (P301L) 293T cell model. Collectively, harmine-based derivatives could be considered as possible drug leads for the development of AD therapies.
Background: Alzheimer's disease is a multifactorial neurological disorder seen in elderly people. Loss of cholinergic transmission and unbalanced tryptophan metabolism kynurenine pathway have been demonstrated in neuropsychiatric diseases. Methods & results: Among the two series of synthesized compounds, compounds 5c and 5h were identified as effective dual BChE/IDO1 inhibitors, with well-balanced micromolar activity. Compounds 5c and 5h exhibited promising ability to ameliorate behavioral impairment by Morris water maze. The safety of miconazole analogs was also validated by PC12 and SH-SY5Y cell lines. Conclusion: These results highlight the ability of 5c and 5h to treat Alzheimer's disease.
Title: Long non-coding RNA ABHD11-AS1 promotes colorectal cancer progression and invasion through targeting the integrin subunit alpha 5/focal adhesion kinase/phosphoinositide 3 kinase/Akt signaling pathway Luo J, Jiang Y, Wu L, Zhuo D, Zhang S, Jiang X, Sun Y, Huang Y Ref: Aging (Albany NY), 13:20179, 2021 : PubMed
Long non-coding (lnc)RNA ABHD11-AS1 participates in the development and progress of various cancers, but its role in colorectal cancer (CRC) remains poorly known. In the present study, public database analysis and quantitative reverse transcription PCR of CRC and normal tissues showed that ABHD11-AS1 was overexpressed in CRC and associated with poor prognosis in CRC patients. Both in vitro and in vivo experiments demonstrated that loss-of-function of ABHD11-AS1 attenuated the proliferation, migration, and invasion of CRC cells and induced their apoptosis. Transcriptome sequencing and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis indicated that the phosphoinositide 3 kinase (PI3K)/Akt signaling pathway is a potential target of ABHD11-AS1. Additionally, we noted that ABHD11-AS1 deficiency reduced integrin subunit alpha (ITGA)5 expression, and impaired the phosphorylation of P85, focal adhesion kinase (FAK), and Akt1 in CRC cell lines and tumor tissues of nude mice. Furthermore, we observed that ITGA5 overexpression abrogated the effect of ABHD11-AS1 knockdown on the proliferation and invasion abilities of CRC cells. Taken together, our studies suggest that lncRNA ABHD11-AS1 promotes proliferation, migration, and invasion in CRC by activating the ITGA5/Fak/PI3K/Akt signaling pathway, and that the ITGA5/Fak/PI3K/Akt axis is a promising target for CRC therapy.
Title: The enantioselective toxicity and oxidative stress of dinotefuran on zebrafish (Danio rerio) Ran L, Yang Y, Zhou X, Jiang X, Hu D, Lu P Ref: Ecotoxicology & Environmental Safety, 226:112809, 2021 : PubMed
Dinotefuran is a widely used neonicotinoid pesticides in agriculture and it has certain ecological toxicity to aquatic organisms. Studies on the potential toxicological effects of dinotefuran on fish are limited. In the present study, 96 h acute toxicity test indicated that enantiomers of R-(-)-dinotefuran had a greater toxic effect than Rac-dinotefuran on zebrafish, and S-(+)-dinotefuran was the least. In chronic assay, R-(-)-dinotefuran exerted more effects on the development of zebrafish than S-(+)-dinotefuran, and dinotefuran also had enantioselective effect on oxidative stress. Significant changes were observed in the superoxide dismutase (SOD), glutathione S-transferase (GST) and acetylcholinesterase (AChE) activities and malondialdehyde (MDA) contents, which demonstrated dinotefuran induced oxidative stress in zebrafish. Besides, through an ultra-performance liquid chromatography quadrupole-TOF mass spectrometry (UPLC-Q-TOF-MS)-based metabolomics method was used to evaluate the enantioselectivity of dinotefuran enantiomers in zebrafish. The results indicated that R-(-)-dinotefuran caused greater disturbances of endogenous metabolites. Phenylalanine metabolic pathways, glycine, serine and threonine metabolic pathways are only involved in zebrafish exposed to R-(-)-dinotefuran; whereas phenylalanine, tyrosine and tryptophan biosynthesis was only involved in zebrafish exposed to S-(+)-dinotefuran. This study provides a certain reference value for assessing the environmental risks of dinotefuran enantiomers to aquatic organisms, and has practical significance for guiding the ecologically and environmentally safety use of dinotefuran.
Title: Novel pyridine-containing sultones: Structure-activity relationship and biological evaluation as selective AChE inhibitors for the treatment of Alzheimer's disease Tang W, Zhang H, Wu C, Chen X, Zhang Z, Jiang X, Qin HL Ref: ChemMedChem, :, 2021 : PubMed
Novel pyridine-containing sultones were synthesized and evaluated for their ChE inhibitory activity. Most of compounds showed selective AChE inhibitory activity. The structure-activity relationship (SAR) showed: (i) fused pyridine-containing sultones increased the AChE inhibition, series B > series A ; (ii) series B with halo-phenyl had better activity. Compound B4 was identified as a selective AChE inhibitor (IC 50 = 8.93 microM), which was nicely fallen into Tc AChE via hydrogen interactions between delta-pyridylsultone scaffold with Asp72, Ser122, Phe288, Phe290 and Trp84. Compound B4 showed reversible and non-competitive ( K i = 7.67 microM) AChE inhibition, nontoxicity and remarkable neuro-protective activity. In vivo studies confirmed that compound B4 significantly ameliorates performances of scopolamine-treated C57BL/6J mice, suggesting a significant benefit of AChE inhibition for a disease-modifying treatment of AD.
Title: Systematic Analysis and Biochemical Characterization of the Caffeoyl Shikimate Esterase Gene Family in Poplar Wang X, Chao N, Zhang A, Kang J, Jiang X, Gai Y Ref: Int J Mol Sci, 22:, 2021 : PubMed
Caffeoyl shikimate esterase (CSE) hydrolyzes caffeoyl shikimate into caffeate and shikimate in the phenylpropanoid pathway. In this study, we performed a systematic analysis of the CSE gene family and investigated the possible roles of CSE and CSE-like genes in Populus. We conducted a genome-wide analysis of the CSE gene family, including functional and phylogenetic analyses of CSE and CSE-like genes, using the poplar (Populus trichocarpa) genome. Eighteen CSE and CSE-like genes were identified in the Populus genome, and five phylogenetic groups were identified from phylogenetic analysis. CSEs in Group Ia, which were proposed as bona fide CSEs, have probably been lost in most monocots except Oryza sativa. Primary functional classification showed that PoptrCSE1 and PoptrCSE2 had putative function in lignin biosynthesis. In addition, PoptrCSE2, along with PoptrCSE12, might also respond to stress with a function in cell wall biosynthesis. Enzymatic assay of PoptoCSE1 (Populus tomentosa), -2 and -12 showed that PoptoCSE1 and -2 maintained CSE activity. PoptoCSE1 and 2 had similar biochemical properties, tissue expression patterns and subcellular localization. Most of the PoptrCSE-like genes are homologs of AtMAGL (monoacylglycerol lipase) genes in Arabidopsis and may function as MAG lipase in poplar. Our study provides a systematic understanding of this novel gene family and suggests the function of CSE in monolignol biosynthesis in Populus.
Title: Structure-activity relationship, in vitro and in vivo evaluation of novel dienyl sulphonyl fluorides as selective BuChE inhibitors for the treatment of Alzheimer's disease Wu C, Zhang G, Zhang ZW, Jiang X, Zhang Z, Li H, Qin HL, Tang W Ref: J Enzyme Inhib Med Chem, 36:1860, 2021 : PubMed
To discover novel scaffolds as leads against dementia, a series of delta-aryl-1,3-dienesulfonyl fluorides with alpha-halo, alpha-aryl and alpha-alkynyl were assayed for ChE inhibitory activity, in which compound A10 was identified as a selective BuChE inhibitor (IC(50) = 0.021 microM for eqBChE, 3.62 microM for hBuChE). SAR of BuChE inhibition showed: (i) o- > m- > p-; -OCH(3) > -CH(3) > -Cl (-Br) for delta-aryl; (ii) alpha-Br > alpha-Cl, alpha-I. Compound A10 exhibited neuroprotective, BBB penetration, mixed competitive inhibitory effect on BuChE (K(i) = 29 nM), and benign neural and hepatic safety. Treatment with A10 could almost entirely recover the Abeta(1-42)-induced cognitive dysfunction to the normal level, and the assessment of total amount of Abeta(1-42) confirmed its anti-amyloidogenic profile. Therefore, the potential BuChE inhibitor A10 is a promising effective lead for the treatment of AD.
Title: Alpha/Beta-Hydrolase Domain-Containing 6: Signaling and Function in the Central Nervous System Zhang H, Li X, Liao D, Luo P, Jiang X Ref: Front Pharmacol, 12:784202, 2021 : PubMed
Endocannabinoid (eCB) signaling plays an important role in the central nervous system (CNS). alpha/beta-Hydrolase domain-containing 6 (ABHD6) is a transmembrane serine hydrolase that hydrolyzes monoacylglycerol (MAG) lipids such as endocannabinoid 2-arachidonoyl glycerol (2-AG). ABHD6 participates in neurotransmission, inflammation, brain energy metabolism, tumorigenesis and other biological processes and is a potential therapeutic target for various neurological diseases, such as traumatic brain injury (TBI), multiple sclerosis (MS), epilepsy, mental illness, and pain. This review summarizes the molecular mechanisms of action and biological functions of ABHD6, particularly its mechanism of action in the pathogenesis of neurological diseases, and provides a theoretical basis for new pharmacological interventions via targeting of ABHD6.
Title: Comparative assessment of neurotoxicity impacts induced by alkyl tri-n-butyl phosphate and aromatic tricresyl phosphate in PC12 cells Chang Y, Cui H, Jiang X, Li M Ref: Environ Toxicol, 35:1326, 2020 : PubMed
Organophosphate flame retardants (OPFRs) have become a growing concern due to their potential environmental and health risk. However, limited studies have described the toxicity, particularly neurotoxicity of alkyl and aromatic OPFRs. This study investigated the neurotoxicity of alkyl tri-n-butyl phosphate (TnBP) and aromatic tricresyl phosphate (TCP) to rat adrenal pheochromocytoma (PC12) cells for 24h. Viability detection showed dose-response toxicity effect of TCP and TnBP to PC12 cells. The half-maximal inhibitory concentration of 24h (24h-IC(50) ) of TCP and TnBP were 2415.61 and 338.09microM, respectively. Both TnBP and TCP significantly changed the acetylcholinesterase (AChE) activity, and TnBP is more likely to cause neurotoxicity to PC12 cells compared to TCP. Also, The results of LDH and caspase-3 activity detection as well as Hoechst staining suggested that cell apoptosis induced by TCP and TnBP may be the primary pathway. These findings provide a toxicity data of aromatic and alkyl-substituted OPFRs to PC12 cells, and a new insight into the toxicity of OPFRs on health risk assessment.
Plant tannins, including condensed tannins (CTs) and hydrolyzable tannins (HTs), are widely distributed in the plant kingdom. To date, tannase (TA) - is a type of tannin acyl-hydrolase hydrolyzing HTs, CT monomer gallates and depsides - has been reported in microbes only. Whether plants express TA remains unknown. Herein, we report plant TA genes. A native Camellia sinensis TA (CsTA) is identified from leaves. Six TAs are cloned from tea, strawberry (Fragariasxsananassa, Fa) and four other crops. Biochemical analysis shows that the native CsTA and six recombinant TAs hydrolyze tannin compounds, depsides and phenolic glycosides. Transcriptional and metabolic analyses reveal that the expression of CsTA is oppositely associated with the accumulation of galloylated catechins. Moreover, the transient overexpression and RNA interference of FaTA are positively associated with the accumulation of ellagitannins in strawberry fruit. Phylogenetic analysis across different kingdoms shows that 29 plant TA homologs are clustered as a plant-specific TA clade in class I carboxylesterases. Further analysis across the angiosperms reveals that these TA genes are dispersed in tannin-rich plants, which share a single phylogenetic origin c. 120 million yr ago. Plant TA is discovered for the first time in the plant kingdom and is shown to be valuable to improve tannin compositions in plants.
Title: Novel deoxyvasicinone and tetrahydro-beta-carboline hybrids as inhibitors of acetylcholinesterase and amyloid beta aggregation Du H, Jiang X, Ma M, Xu H, Liu S, Ma F Ref: Bioorganic & Medicinal Chemistry Lett, :127659, 2020 : PubMed
A novel series of deoxyvasicinone-tetrahydro-beta-carboline hybrids were synthesized and evaluated as acetylcholinesterase (AChE) and beta-amyloid peptide (Abeta) aggregation inhibitors for the treatment of Alzheimer's disease. The results revealed that the derivatives had multifunctional profiles, including AChE inhibition, Abeta(1-42) aggregation inhibition, and neuroprotective properties. Inspiringly, hybrids 8b and 8d displayed excellent inhibitory activities against hAChE (IC(50) = 0.93 and 1.08 nM, respectively) and Abeta(1-42) self-aggregation (IC(50) = 19.71 and 2.05 M, respectively). In addition, 8b and 8d showed low cytotoxicity and good neuroprotective activity against Abeta(1-42)-induced damage in SH-SY5Y cells.
A key factor in the success of the MTDLs drug discovery approach is the selection of suitable target proteins. Based on the results of our previous research regarding dual-target inhibitors of AChE/GSK-3beta and analysis of target proteins, in the current study, 28 hybrids were designed and synthesized. Docking studies allowed us to rationalize the binding mode of the synthesized compounds in both targets. In vitro enzyme inhibition studies identified compound GT15 as a lead molecule with preferential AChE/GSK-3beta inhibition (hAChE IC(50) = 1.2 +/- 0.1 nM; hGSK-3beta IC(50) = 22.2 +/- 1.4 nM). In addition, GT15 showed high kinase selectivity for GSK-3, except for DYRK1, with inhibition rate of 83.69% and 67.94% against DYRK1alpha and DYRK1beta at a concentration of 20 muM. The compound also exhibited good permeability across the blood-brain-barrier and ability to inhibit the phosphorylation of tau protein. Upon oral administration, GT15 exhibited promising cognitive improvement in the scopolamine-induced cognitive deficit mice in the Morris water maze model. These results suggest that AChE and GSK-3 based multitargeted approach have therapeutic potential for Alzheimer's disease.
In the present work, a novel series of pyridinethiazole bearing benzylpiperidine hybrids were designed and synthesized as dual-target inhibitors of GSK-3beta/AChE. Among them, GD29 was the most promising candidate, with an IC(50) value of 0.3 M for hAChE and an IC(50) value of 0.003 M for hGSK-3beta, respectively. The compounds exhibited good drug-like properties with optimal inhibitory enzyme activities. Moreover, GD29 showed anti-inflammatory properties at micromolar concentrations and displayed interesting neuroprotective profiles in an in vitro model of oxidative stress-induced neuronal death. Notably, the compounds also exhibited good permeability across the blood-brain-barrier (BBB) both in vitro. Central cholinomimetic activity was confirmed using a scopolamine-induced cognition impairment model in Institute of Cancer Research (ICR) mice upon oral administration. The current work identified optimized compounds and explored the therapeutic potential of glycogen synthase kinase 3/cholinesterase inhibition for the treatment of AD.
INTRODUCTION: Myasthenia gravis (MG) is an autoimmune disease in which antibodies directly target components of the neuromuscular junction, causing neuromuscular conduction damage that leads to muscle weakness. The current pharmaceutical treatment for MG is still not ideal to address the problems of disease progression, high recurrence rate, and drug side effects. Clinical observations suggest that traditional Chinese medicine (TCM) can strengthen immunity and improve symptoms of MG patients, delay the progression of the disease, reduce or even prevent the need for immunosuppressive therapy when used in combination with acetylcholinesterase inhibitors or low-dose prednisone, as well as improve the quality of life of patients. The Qiangji Jianli Capsule (QJC) is a combination of medicinal herbs which is used in traditional Chinese medicine. Since MG is a rare disorder, randomized controlled trials comparing large cohorts are difficult to conduct. Therefore, we proposed to aggregate data from a small series of N-of-1 trials to assess the effect of the Chinese medical prescription QJC, which strengthens the spleen and nourishes Qi, as an add-on treatment for MG with spleen and stomach Qi deficiency syndrome. METHODS AND ANALYSIS: Single-center, randomized, double-blind, multiple crossover N-of-1 studies will compare QJC versus placebo in 5 adult MG patients with spleen and stomach Qi deficiency syndrome. Patients will undergo 3 cycles of two 4-week intervention periods. According to the treatment schedule, patients will continue to be treated with pyridine bromide tablets, prednisone acetate, tablets and/or tacrolimus capsules throughout the entire trial. Each period consisting of 4-week oral add-on treatment with QJC will be compared with 4-week add-on treatment with a placebo. The primary endpoints are quantitative myasthenia gravis (QMG) test; measurement of the amount of Treg cells and cytokines such as interferon-gamma (IFN-gamma), interleukin-4 (IL-4), interleukin-17A (IL-17A), and transforming growth factor-beta (TGF-beta); and corticosteroid or immunosuppressive agent dosage. Secondary outcome measures: Clinical: Evaluation of the effect of TCM syndromes; MG-activities of daily living (MG-ADL) scales; adverse events. ETHICS AND DISSEMINATION: This study was approved by The First Affiliated Hospital of Guangzhou University of Chinese Medicine (GZUCM), No. ZYYECK[2019]038. The results will be published in a peer-reviewed publication. Regulatory stakeholders will comment on the suitability of the trial for market authorization and reimbursement purposes. Trial registration: Chinese Clinical Trial Register, ID: ChiCTR2000033516. Registered on 3 June 2020, http://www.chictr.org.cn/showprojen.aspx?proj=54618.
Title: Soluble epoxide hydrolase inhibitor protects against blood-brain barrier dysfunction in a mouse model of type 2 diabetes via the AMPK/HO-1 pathway Wu J, Zhao Y, Fan Z, Chen Q, Chen J, Sun Y, Jiang X, Xiao Q Ref: Biochemical & Biophysical Research Communications, :, 2020 : PubMed
Diabetes mellitus is a metabolic disorder that can lead to blood-brain barrier (BBB) disruption and cognitive decline. However, the mechanisms of BBB breakdown in diabetes are still unclear. Soluble epoxide hydrolase (sEH) is an enzyme that degrades epoxyeicosatrienoic acids (EETs), which have multiple protective effects on vascular structure and functions. In the current study, we showed increased vascular permeability of the BBB, which was accompanied by upregulation of sEH and downregulation of 14,15-EET. Moreover, the sEH inhibitor t-AUCB restored diabetic BBB integrity in vivo, and 14,15-EET prevented ROS accumulation and MEC injury in vitro. t-AUCB or 14,15-EET treatment provoked AMPK/HO-1 activation under diabetic conditions in vivo and in vitro. Thus, we suggest that decreased EET degradation by sEH inhibition might be a potential therapeutic approach to attenuate the progression of BBB injury in diabetic mice via AMPK/HO-1 pathway activation.
Title: The structure-based optimization of delta-sultone-fused pyrazoles as selective BuChE inhibitors Zhang Z, Min J, Chen M, Jiang X, Xu Y, Qin H, Tang W Ref: Eur Journal of Medicinal Chemistry, 201:112273, 2020 : PubMed
Structure-based optimization was conducted to improve the potency and selectivity of BuChE inhibitors with delta-sulfonolactone-fused pyrazole scaffold. By mimicking the hydrophobic interactions of donepezil at PAS, the introduction of a tertiary benzylamine at 5-position can significantly increase BuChE inhibitory activity. Compounds C4 and C6 were identified as high selective nanomolar BuChE inhibitors (IC50 = 8.3 and 7.7 nM, respectively), which exhibited mild antioxidant capacity, nontoxicity, lipophilicity and neuroprotective activity. Kinetic studies showed that BuChE inhibition of compound C6 was mixed-type against BuChE (Ki = 24 nM) and >2000-fold selectivity for BuChE over AChE. The proposed binding mode of new inhibitors was consistent with the results of structure-activity relationship analysis.
Nanoscale field-effect transistors (FETs) represent a unique platform for real time, label-free transduction of biochemical signals with unprecedented sensitivity and spatiotemporal resolution, yet their translation toward practical biomedical applications remains challenging. Herein, we demonstrate the potential to overcome several key limitations of traditional FET sensors by exploiting bioactive hydrogels as the gate material. Spatially defined photopolymerization is utilized to achieve selective patterning of polyethylene glycol on top of individual graphene FET devices, through which multiple biospecific receptors can be independently encapsulated into the hydrogel gate. The hydrogel-mediated integration of penicillinase was demonstrated to effectively catalyze enzymatic reaction in the confined microenvironment, enabling real time, label-free detection of penicillin down to 0.2 mM. Multiplexed functionalization with penicillinase and acetylcholinesterase has been demonstrated to achieve highly specific sensing. In addition, the microenvironment created by the hydrogel gate has been shown to significantly reduce the nonspecific binding of nontarget molecules to graphene channels as well as preserve the encapsulated enzyme activity for at least one week, in comparison to free enzymes showing significant signal loss within one day. This general approach presents a new biointegration strategy and facilitates multiplex detection of bioanalytes on the same platform, which could underwrite new advances in healthcare research.
Title: Neuroprotective Effect of Resveratrol via Activation of Sirt1 Signaling in a Rat Model of Combined Diabetes and Alzheimer's Disease Ma X, Sun Z, Han X, Li S, Jiang X, Chen S, Zhang J, Lu H Ref: Front Neurosci, 13:1400, 2019 : PubMed
Background: Alzheimer's disease (AD) and diabetes mellitus (DM) often coexist in patients because having one of these conditions increases risk for the other. These two diseases share several pathophysiological mechanisms, such as specific inflammatory signaling pathways, oxidative stress, and cell apoptosis. It is still unclear exactly which mechanisms associated with DM are responsible for increased AD risk. Studies have found that even transient elevation of brain Abeta levels can allow T2DM to slightly disrupt the neural milieu in a way that encourages pathologies associated with the onset of memory deficits and AD. A recent study argues that a potential common pathogenetic mechanism underlying both DM and AD is evidenced by the cooccurrence of amyloid brain legions and deposits containing both tau and Abeta in pancreatic beta cells. Given these links, an investigation detailing disease mechanisms as well as treatment options for patients with cooccurring DM and AD is urgently needed. The biological effects of resveratrol relevant to DM and AD treatment include its abilities to modulate oxidative stress and reduce inflammation. A rat model of DM and concomitant AD was created for this study using intraperitoneal injection of streptozotocin and hippocampal injection of Abeta1-40 to characterize resveratrol's potential protective action. Results: Resveratrol significantly increased the Sirt1 expression, inhibited the memory impairment, the increased acetylcholinesterase, malondialdehyde, interleukin-1beta and interleukin 6 levels, and the decreased levels of choline acetyltransferase (ChAT), superoxide dismutase (SOD), and glutathione in this rat model of diabetes and concomitant AD. The Sirt 1 inhibitor EX527 partially reversed the effects of resveratrol. Conclusion: This study suggests that resveratrol may have a neuroprotective action through activation of Sirt1 signaling in diabetes and AD with concurrent onset.
The recent intentional use of nerve agents and pesticides in Europe and Afghanistan highlights the need for an effective countermeasure against organophosphates (OP) toxins. The most developed pretreatment candidate to date is plasma (native) human butyrylcholinesterase (HuBChE), which is limited in availability and because of its 1:1 stoichiometry with OPs, a large dose will present challenges when delivered parenterally both in terms of pharmacokinetics and manageability in the field. A tetrameric recombinant (r) form of human BChE produced in CHO-K1 cells with similar structure, in vivo stability and antidotal efficacy as the native form, has been developed to deliver rHuBChE as an aerosol (aer) to form a pulmonary bioshield capable of neutralizing inhaled OPs in situ and prevent AChE inhibition in the blood and in the brain; the latter associated with the symptoms of OP toxicity. Previous proof-of-concept macaque studies demonstrated that delivery of 9mg/kg using a microsprayer inserted down the trachea, resulted in protection against an inhaled dose of 15ug/kg of aer-paraoxon (aer-Px) given 72h later. In the present studies, pulmonary delivery of rHuBChE in macaques was achieved using Aerogen vibrating mesh nebulizers, similar to that used for human self-administration. The promising findings indicate that despite the poor lung deposition observed in macaques using nebulizers (13-20%), protective levels of RBC-AChE were still present in the blood even when exposure aer-Px (55mug/kg) was delayed for five days. This long term retention of 5mg/kg rHuBChE deposited in the lung bodes well for the use of an aer-rHuBChE pretreatment in humans where a user-friendly customized nebulizer with increased lung deposition up to 50% will provide even longer protection at a lower dose.
Title: Protective effects of enzyme degradation extract from Porphyra yezoensis against oxidative stress and brain injury in D-galactose-induced aging mice Wang C, Shen Z, Yu J, Yang J, Meng F, Jiang X, Zhu C Ref: British Journal of Nutrition, :1, 2019 : PubMed
This study investigated the effects of Porphyra yezoensis enzyme degradation extract (PYEDE) on the brain injuries and neurodegenerative diseases due to oxidative stress. We used in vitro antioxidant systems to verify the antioxidant potential of PYEDE. The results indicated that PYEDE alleviated weight loss and organ atrophy, reduced the levels of lipid peroxidation and protein carbonylation, and elevated glutathione (GSH) content in the serum and brains of the D-gal-induced aging model mice. PYEDE also renewed the glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), and total anti-oxidant capability (T-AOC) activities, downregulated the inducible nitric oxide synthase (iNOS) activity and nitric oxide (NO) levels, normalized the hippocampal neurons, and modulated multiple neurotransmitter systems by inhibiting the activities of acetylcholinesterase (AchE) and monoamine oxidase (MAO) in the upregulation of acetylcholine (Ach), dopamine (DA) and norepinephrine (NE) levels. Overall, PYEDE is a promising supplement for the alleviation of oxidative stress and age-associated brain diseases.
Title: Discovery of delta-sultone-fused pyrazoles for treating Alzheimer's disease: Design, synthesis, biological evaluation and SAR studies Xu Y, Zhang Z, Jiang X, Chen X, Wang Z, Alsulami H, Qin HL, Tang W Ref: Eur Journal of Medicinal Chemistry, 181:111598, 2019 : PubMed
A class of novel delta-sulfonolactone-fused pyrazole scaffold was prepared via sulfur (VI) fluoride exchange (SuFEx) chemistry using aryl sulfonyl fluorides and pyrazolones. Enzyme screening revealed their cholinesterase inhibitory activity, among them, compounds 4a, 5a and 5d were identified as highly selective submicromolar BuChE inhibitors (IC50=0.20, 0.46 and 0.42muM, respectively), which exhibited nontoxicity, lipophilicity and remarkable neuroprotective activity. Kinetic studies showed that BuChE inhibition of compounds 5a and 5d was reversible, mixed-type and non-competitive inhibition against BuChE (Ki=145nM and 60nM, respectively). Compound 5d can be accommodated into hBuChE via pi-S interaction and hydrophobic interactions. The title compounds are potentially symptomatic treatment in progressive Alzheimer's disease.
Postoperative cognitive dysfunction (POCD) is consistently associated with increased morbidity and mortality. However, its mechanism remains poorly understood. We hypothesized that central cholinergic neuronal degeneration facilitates the development of POCD. The impact of anesthesia/surgery (appendectomy) on learning and memory and the levels of choline acetyltransferase (ChAT), acetylcholinesterase (AChE), vesicular acetylcholine transporter (VAChT), and choline transporter (CHT) in adult and aged mice were measured. Separate cohorts were analyzed after pretreatment with donepezil, an AChE inhibitor, in aged mice or with murine-p75-saporin (mu-p75-sap), a cholinergic-specific immunotoxin, in adult mice. Morris Water Maze was used to measure the learning and memory changes after anesthesia/surgery. Western blot was used to measure the changes in the protein levels of the biomarkers of the central cholinergic system. We found that anesthesia/surgery-induced memory decline and attenuation of central cholinergic biomarkers (ChAT and VAChT) in aged mice but not in adult mice. Donepezil pretreatment reduced central cholinergic impairment in the aged mice and prevented learning and memory declines after anesthesia/surgery. In contrast, when central cholinergic neurons were pre-injured with mu-p75-sap, cognitive dysfunction developed in the adult mice after anesthesia/surgery. These data suggest that central cholinergic neuronal degeneration facilitates the development of POCD.
Small molecule cholinesterases inhibitor (ChEI) provides an effective therapeutic strategy to treat Alzheimer's disease (AD). Currently, the discovery of new ChEI with multi-target effect is still of great importance. Herein, we report the synthesis, structure-activity relationship study and biological evaluation of a series of tacrine-cinnamic acid hybrids as new ChEIs. All target compounds are evaluated for their in vitro cholinesterase inhibitory activities. The representatives which show potent activity on cholinesterase, are evaluated for the amyloid beta-protein self-aggregation inhibition and in vivo assays. The optimal compound 19, 27, and 30 (human AChE IC50 = 10.2 +/- 1.2, 16.5 +/- 1.7, and 15.3 +/- 1.8 nM, respectively) show good performance in ameliorating the scopolamine-induced cognition impairment and preliminary safety in hepatotoxicity evaluation. These compounds deserve further evaluation for the development of new therapeutic agents against AD.
Title: Redox-Controlled Fluorescent Nanoswitch Based on Reversible Disulfide and Its Application in Butyrylcholinesterase Activity Assay Chen G, Feng H, Jiang X, Xu J, Pan S, Qian Z Ref: Analytical Chemistry, 90:1643, 2018 : PubMed
Butyrylcholinesterase (BChE) mainly contributing to plasma cholinesterase activity is an important indicator for routinely diagnosing liver function and organophosphorus poisoning in clinical diagnosis, but its current assays are scarce and frequently suffer from some significant interference and instability. Herein, we report a redox-controlled fluorescence nanoswtich based on reversible disulfide bonds, and further develop a fluorometric assay of BChE via thiol-triggered disaggregation-induced emission. Thiol-functionalized carbon quantum dots (thiol-CQDs) with intense fluorescence is found to be responsive to hydrogen peroxide, and their redox reaction transforms thiol-CQDs to nonfluorescent thiol-CQD assembly. The thiols inverse this process by a thiol-exchange reaction to turn on the fluorescence. The fluorescence can be reversibly switched by the formation and breaking of disulfide bonds caused by external redox stimuli. The specific thiol-triggered disaggregation-induced emission enables us to assay BChE activity in a fluorescence turn-on and real-time way using butyrylthiocholine iodide as the substrate. As-established BChE assay achieves sufficient sensitivity for practical determination in human serum, and is capable of avoiding the interference from micromolar glutathione and discriminatively quantifying BChE from its sister enzyme acetylcholinesterase. The first design of reversible redox-controlled nanosiwtch based on disulfide expands the application of disulfide chemistry in sensing and clinical diagnostics, and this novel BChE assay enriches the detection methods for cholinesterase activity.
Title: Protective Effect of Hyperforin on beta Amyloid Protein Induced Apoptosis in PC12 Cells and Colchicine Induced Alzheimer's Disease: An Anti-oxidant and Anti-inflammatory Therapy Jiang X, Kumar M, Zhu Y Ref: J Oleo Sci, 67:1443, 2018 : PubMed
The current investigation aimed to scrutinize the neuro-protective effect of hyperforin on betaamyloid peptide (Abeta)1-42 and H2O2 induced injury in PC12 cells and colchicine induced Alzheimer's disease (AD). PC12 cells were treated with H2O2 and (Abeta)1-42 in the presence of hyperforin. The cell viability was determined via suing the MTT assay; malondialdehyde (MDA) and lactate dehydrogenase (LDH) levels were also scrutinized. Colchicine induced the destruction of memory and learning which was exhibited in neurobehavioral theory (passive avoidance and Morris water maze) connected with reduced activity of acetylcholinesterase (AChE). Antioxidant and inflammatory parameters also estimated. Hyperforin dose dependently increased the cell viability and reduced the MDA and LDH release via PC12 cell injured with H2O2 and (Abeta)1-42. Hyperforin treatment lead to a considerable enhance in TLT in the retention trials as comparisian to acquisition trial suggesting as boosting memory and learning in rats. Hyperforin treatments significantly increase the AChE and reduced the superoxide dismutase, glutathione, MDA, protein carbonyl, glutathione peroxdiase, catalase, NFkB and IL1beta at dose dependent manner. In summary, the model of H2O2 and (Abeta)1-42 induced PC12 cell injury was successfully developed and dose dependently treatment of hypoforin showed the neuroprotective effect against the H2O2 and (Abeta)1-42 induced cell damage. These finding clearly exhibited that hyperforin reverted the colchicine induced neurochemical and behavioural alteration via potent antiinflammatory and antioxidant activity.
Title: Modified Buzhong Yiqi decoction for myasthenia gravis: A systematic review protocol Jiang X, Chen G, Huang J, Xie L, Shen D, Jiang K, Xu H Ref: Medicine (Baltimore), 97:e13677, 2018 : PubMed
BACKGROUND: Myasthenia gravis (MG) is an autoimmune disease caused by the transmission of dysfunction in the neuromuscular junction, manifesting partial or systemic skeletal muscle weakness and fatigue, which are exacerbated by activities and relieved after rest. Currently, the conventional therapy is applying cholinesterase inhibitors, steroids, immunosuppressant, and thymectomy. However, these drugs have obvious side effects. According to traditional Chinese medicine (TCM) theory, Buzhong Yiqi decoction (BYD) is a Qi-supplementing formula which is suitable for MG management as MG is generally diagnosed as "flaccidity syndrome" and considered caused by Qi-deficiency. An increasing number of clinical controlled studies also have found that BYD could improve the efficacy and reduced adverse effects in treating MG, but there is no systematic review of it. Therefore, we will use meta-analysis to evaluate the efficacy and safety of BYD for MG. METHODS: PubMed, MEDLINE, EMBASE, Cochrane Library, China National Knowledge Infrastructure (CNKI), Wanfang data, Chinese Scientific Journals Database (VIP), and China biomedical literature database (CBM) will be searched to obtain the eligible studies published up to June 1, 2018. The primary outcome will be clinical absolute score before and after treatment, clinical relative score as well as effective rate. The secondary outcome will be the concentration of acetylcholine receptor antibody (AchRAb) in serum and adverse events incidence. Data analysis will be conducted using RevMan5.3 and Stata V.9.0 software. Trial sequential analysis (TSA) will be performed to assess the risk of random error and the validity of conclusion using TSA program version 0.9 beta. RESULTS: This systematic review will provide a high-quality synthesis of BYD and its modified forms for MG from various evaluation aspects including clinical absolute score before and after treatment, clinical relative score, effective rate, the concentration of AchRAb in serum and adverse events incidence. CONCLUSION: The systematic review will provide evidence to assess the efficacy and safety of BYD and its modified forms in the treatment of MG. PROSPERO REGISTRATION NUMBER: PROSPERO CRD42018095241.
In our endeavor towards the development of potent multi-target ligands for the treatment of Alzheimer's disease, miconazole was identified to show BuChE-IDO1 dual-target inhibitory effects. Morris water maze test indicated that miconazole obviously ameliorated the cognitive function impaired by scopolamine. Furthermore, it showed good safety in primary hepatotoxicity evaluation. Based on these results, we designed, synthesized, and evaluated a series of miconazole derivatives as BuChE-IDO1 dual-target inhibitors. Out of the 12 compounds, 5i and 5j exhibited the best potency in enzymatic evaluation, thus were selected for subsequent behavioral study, in which the two compounds exerted much improved effect than tacrine. Meanwhile, 5i and 5j displayed no apparent hepatotoxicity. The results suggest that miconazole analogue offers an attractive starting point for further development of new BuChE-IDO1 dual-target inhibitors against Alzheimer's disease.
Fatalities from organophosphate (OP) insecticide result from both occupational and deliberate exposure; significantly impacting human health. Like nerve agents, insecticides are neurotoxins which target and inhibit acetylcholinesterases (AChE) in central and peripheral synapses in the cholinergic nervous system. Post-exposure therapeutic countermeasures generally include administration of atropine with a pyridinium aldoximes e.g. pralidoxime, to reactivate the OP-inhibited AChE. However, commonly used oximes inefficiently cross the blood brain barrier and are rapidly cleared and their benefit is debated. Recent findings have demonstrated the ability of a novel zwitterionic, centrally acting, brain penetrating oxime (RS194B) to reverse severe symptoms and rapidly reactivate sarin-inhibited AChE in macaques but has not been tested following OP pesticide poisoning. The severe symptoms following a lethal dose of inhaled paraoxon (100ug/kg), which mimicked those in insecticide poisoned individuals, were rapidly reversed in macaques by post-exposure IM administration of 80mg/kg of RS194B. This occurred with a concomitant reactivation of AChE to 40-100% in <1hr and BChE (40% in 8hr). These findings will be used to develop a macaque model with RS194B as a post-exposure treatment for insecticide poisoning and generate efficacy data for approval under the FDA Animal rule.
Tea, one of the world's most important beverage crops, provides numerous secondary metabolites that account for its rich taste and health benefits. Here we present a high-quality sequence of the genome of tea, Camellia sinensis var. sinensis (CSS), using both Illumina and PacBio sequencing technologies. At least 64% of the 3.1-Gb genome assembly consists of repetitive sequences, and the rest yields 33,932 high-confidence predictions of encoded proteins. Divergence between two major lineages, CSS and Camellia sinensis var. assamica (CSA), is calculated to approximately 0.38 to 1.54 million years ago (Mya). Analysis of genic collinearity reveals that the tea genome is the product of two rounds of whole-genome duplications (WGDs) that occurred approximately 30 to 40 and approximately 90 to 100 Mya. We provide evidence that these WGD events, and subsequent paralogous duplications, had major impacts on the copy numbers of secondary metabolite genes, particularly genes critical to producing three key quality compounds: catechins, theanine, and caffeine. Analyses of transcriptome and phytochemistry data show that amplification and transcriptional divergence of genes encoding a large acyltransferase family and leucoanthocyanidin reductases are associated with the characteristic young leaf accumulation of monomeric galloylated catechins in tea, while functional divergence of a single member of the glutamine synthetase gene family yielded theanine synthetase. This genome sequence will facilitate understanding of tea genome evolution and tea metabolite pathways, and will promote germplasm utilization for breeding improved tea varieties.
Background: Postoperative cognitive dysfunction (POCD) is consistently associated with increased morbidity and mortality, which has become a major concern of patients and caregivers. Although POCD occurs mainly in aged patients, it happens at any age. Previous studies demonstrated that anesthesia/surgery had no effects on reference memory of adult mice. However, whether it impairs working memory remains unclear. Working memory deficit would result in many deficits of executive function. We hypothesized that anesthesia/surgery impaired the working memory of adult mice and the central cholinergic system was involved. Method: Tibial fracture internal fixation under the anesthesia of isoflurane was performed in two-month-old C57BL/6 mice. Two days later, the spatial reference memory and working memory were measured by a Morris Water Maze (MWM). Donepezil, an inhibitor of acetylcholinesterase (AChE), was administered in another cohort mice for 4 weeks. Then, the working memory was measured by MWM 2 days after anesthesia/surgery. Western blot was used to detect the protein levels of acetylcholine transferase (ChAT), AChE, vesicular acetylcholine transporter (VAChT), and choline transporter (ChT) in the prefrontal cortex (PFC). Results: We found that anesthesia/surgery had no effects on the reference memory, but it impaired the working memory in adult mice. Meanwhile, we also found that the protein level of ChAT in PFC decreased significantly compared with that in control group. Donepezil pretreatment prevented working memory impairment and the decrease of the protein levels of ChAT induced by anesthesia/surgery. Conclusion: These results suggest that anesthesia/surgery leads to working memory deficits in adult mice and central cholinergic system impairment is involved.
Title: Ag(+) -Gated Surface Chemistry of Gold Nanoparticles and Colorimetric Detection of Acetylcholinesterase Zhang J, Zheng W, Jiang X Ref: Small, :e1801680, 2018 : PubMed
Chemical regulation of enzyme-mimic activity of nanomaterials is challenging because it requires a precise understanding of the surface chemistry and mechanism, and rationally designed applications. Herein, Ag(+) -gated peroxidase activity is demonstrated by successfully modulating surface chemistry of cetyltrimethylammonium bromide-capped gold nanoparticles (CTAB-AuNPs). A surface blocking effect of long-chain molecules on surfaces of AuNPs that inhibit peroxidase activity of AuNPs is found. Ag(+) ions can selectively bind on the surfaces of AuNPs and competitively destroy CTAB membrane forming Ag(+) @CTAB-AuNPs complexes to result in enhanced peroxidase activity. Ag(+) @CTAB-AuNPs show the highest peroxidase activity compared to similar-sized citrate-capped and ascorbic acid-capped AuNPs. Ag(+) @CTAB-AuNPs can potentially develop into analyte-responsive systems and exhibit advantages in the optical sensing field. For example, the Ag(+) @CTAB-AuNPs system shows an enhanced sensitivity and selectivity for acetylcholinesterase activity sensing compared to other methods.
Stimuli-responsive hydrogels (SRhG) that undergo response to physicochemical stimuli have been broadly applied in separation, biosensing, and drug delivery. Since, most of the SRhG are based on the structural behaviors (swelling or collapse). Herein, we describe a more simple and convenient colorimetric SRhG of polydopamine-coated gold nanoparticles (Au@PDA NPs) hydrogel. The newly developed SRhG is based on the in situ surface chemistry of Au@PDA NPs with core-shell structure embedding in agarose hydrogel. Silver ions can in situ form Ag NPs on surfaces of Au@PDA NPs (Ag_Au@PDA NPs with core-satellites like structure) at ambient conditions, which shift the localized surface plasmon resonance (LSPR) absorption peak and result in color change. The solid sensing phase of SRhG shows greatly improved stability and anti-interference ability comparing to that of solution phase sensing. With rational designs, Au@PDA NPs hydrogel shows great potential in optical sensing, for example, biothiol detection, and coupled with enzyme-cascade reaction for acetylcholinesterase activity detection and inhibitor assays with excellent sensitivity and selectivity.
Paraoxonase 1 gene (PON1) polymorphisms and dietary vegetable and fruit intake are both established determinants of ischemic stroke (IS). However, little is known about whether these factors jointly influence the risk of IS. We analyzed the main effects of PON1, as well as the interactions between PON1 and dietary vegetable or fruit intake with the risk of total IS and its subtypes in a family-based case-control study conducted among 2158 Chinese participants (1007 IS cases and 1151 IS-free controls) from 918 families. Conditional logistic regression models, with each family as a stratum, were used to examine the association between rs662 and IS. Gene-diet interactions were tested by including a cross-product term of dietary vegetable or fruit intake by rs662_G allele count in the models. Each copy of the PON1 rs662_G allele was associated with 28% higher risk of total IS (p = 0.008) and 32% higher risk of large artery atherosclerosis subtype (LAA) (p = 0.01). We observed an interaction between rs662 and vegetable intake for both total IS (p = 0.006) and LAA (p = 0.02) after adjustment for covariates. Individuals who carry the rs662_A allele may benefit to a greater extent from intake of vegetables and thus be more effectively protected from ischemic stroke, whereas carriers of the G allele may still remain at greater risk for ischemic stroke due to their genetic backgrounds even when they consume a high level of vegetables. More studies are needed to replicate our findings among other populations.
Title: Therapeutic Agents in Alzheimer's Disease Through a Multi-targetdirected Ligands Strategy: Recent Progress Based on Tacrine Core Lin H, Li Q, Gu K, Zhu J, Jiang X, Chen Y, Sun H Ref: Curr Top Med Chem, 17:3000, 2017 : PubMed
Alzheimer's Disease (AD) is one of the most common forms of dementia in elderly people. To date, efficacious therapeutic agent for the treatment of AD is still very limited, so it has long been a challenging and attractive task to discover new anti-AD drugs. Considering the multifactorial nature of AD, recently, the concept of Multi-Target-Directed Ligands (MTDLs) has emerged as a new strategy for designing therapeutic agents on AD. MTDLs are believed to exert their effects through simultaneously affecting multiple targets which contribute to etiology of AD. Therefore, MTDLs are considered to be more efficacious than mono-target agents. Tacrine is the first drug approved by Food and Drug Administration (FDA). Although the clinical use of tacrine is restricted because of its hepatotoxicity, the high Ligand Efficiency (LE) of this compound makes it an ideal component for designing MTDLs. This article provides an update review of the advances on the development of MTDLs based on tacrine. Case studies are carefully selected to show the detailed strategy on medicinal modification of Tacrine-Based MTDLs. Finally, several concerns and opinions on designing new MTDLs are discussed as well.
Drug-induced proteome stress that involves protein aggregation may cause adverse effects and undermine the safety profile of a drug. Safety of drugs is regularly evaluated using cytotoxicity assays that measure cell death. However, these assays provide limited insights into the presence of proteome stress in live cells. A fluorogenic protein sensor is reported to detect drug-induced proteome stress prior to cell death. An aggregation prone Halo-tag mutant (AgHalo) was evolved to sense proteome stress through its aggregation. Detection of such conformational changes was enabled by a fluorogenic ligand that fluoresces upon AgHalo forming soluble aggregates. Using 5 common anticancer drugs, we exemplified detection of differential proteome stress before any cell death was observed. Thus, this sensor can be used to evaluate drug safety in a regime that the current cytotoxicity assays cannot cover and be generally applied to detect proteome stress induced by other toxins.
The N-myc downstream regulated gene (NDRG) family consists of 4 members, NDRG-1, -2, -3, -4. Physiologically, we found Ndrg3, a critical gene which led to homologous lethality in the early embryo development, regulated the male meiosis in mouse. The expression of Ndrg3 was enhanced specifically in germ cells, and reached its peak level in the pachytene stage spermatocyte. Haplo-insufficiency of Ndrg3 gene led to sub-infertility during the male early maturation. In the Ndrg3(+/-) germ cells, some meiosis events such as DSB repair and synaptonemal complex formation were impaired. Disturbances on meiotic prophase progression and spermatogenesis were observed. In mechanism, the attenuation of pERK1/2 signaling was detected in the heterozygous testis. With our primary spermatocyte culture system, we found that lactate promoted DSB repair via ERK1/2 signaling in the male mouse germ cells in vitro. Deficiency of Ndrg3 gene attenuated the activation of ERK which further led to the aberrancy of DSB repair in the male germ cells in mouse. Taken together, we reported that Ndrg3 gene modulated the lactate induced ERK pathway to facilitate DSB repair in male germ cells, which further regulated meiosis and subsequently fertility in male mouse.
Title: Post-exposure treatment with the oxime RS194B rapidly reverses early and advanced symptoms in macaques exposed to sarin vapor Rosenberg YJ, Mao L, Jiang X, Lees J, Zhang L, Radic Z, Taylor P Ref: Chemico-Biological Interactions, 274:50, 2017 : PubMed
Organophosphate (OP) nerve agents and pesticides trigger a common mechanism of neurotoxicity resulting from critical targeting and inhibition of acetylcholinesterases (AChE) in central and peripheral synapses in the cholinergic nervous system. Therapeutic countermeasures have thus focused on either administering an oxime post-exposure, that can rapidly reactivate OP-inhibited AChE, or by preventing OP poisoning through administering pre-exposure treatments that scavenge OPs before they inhibit their physiological AChE targets. While several pyridinium aldoxime antidotes are currently approved, their utility is impaired due to their inability to cross the blood-brain barrier (BBB) efficiently. The present study utilized a macaque (Ma) model to demonstrate the efficacy of a novel zwitterionic and centrally acting oxime RS194B to reactivate sarin- and paraoxon-inhibited macaque AChE and butyrylcholinesterase (BChE) in vitro and to further assess the capacity of RS194B to effect a reversal of clinical symptoms following sarin inhalation in vivo. In vitro, oxime reactivation of MaAChE and MaBChE was shown to be comparable to their human orthologs, while the macaque studies indicated that IM administration of 62.5 mg/kg of RS194B and 0.28 mg/kg atropine after continuous exposure to 49.6 mug/kg sarin vapor, rapidly reactivated the inhibited AChE and BChE in blood and reversed both early and advanced clinical symptoms of sarin-induced toxicity following pulmonary exposure within 1 h. The rapid cessation of autonomic and central symptoms, including convulsions, observed in macaques bodes well for the use of RS194B as an intra- or post-exposure human treatment and validates the macaque model in generating efficacy and toxicology data required for approval under the FDA Animal rule.
The discovery of complete ammonia oxidizer (comammox) has fundamentally upended our perception of the global nitrogen cycle. Here, we reported four metagenome assembled genomes (MAGs) of comammox Nitrospira that were retrieved from metagenome datasets of tap water in Singapore (SG-bin1 and SG-bin2), Hainan province, China (HN-bin3) and Stanford, CA, USA (ST-bin4). Genes of phylogenetically distinct ammonia monooxygenase subunit A (amoA) and hydroxylamine dehydrogenase (hao) were identified in these four MAGs. Phylogenetic analysis based on ribosomal proteins, AmoA, hao and nitrite oxidoreductase (subunits nxrA and nxrB) sequences indicated their close relationships with published comammox Nitrospira. Canonical ammonia-oxidizing microbes (AOM) were also identified in the three tap water samples, ammonia-oxidizing bacteria (AOB) in Singapore's and Stanford's samples and ammonia-oxidizing archaea (AOA) in Hainan's sample. The comammox amoA-like sequences were also detected from some other drinking water systems, and even outnumbered the AOA and AOB amoA-like sequences. The findings of MAGs and the occurrences of AOM in different drinking water systems provided a significant clue that comammox are widely distributed in drinking water systems.
The cholinergic impairment is an early marker in Alzheimer's disease (AD), while the mechanisms are not fully understood. We investigated here the effects of glycogen synthase kinse-3 (GSK-3) activation on the cholinergic homoeostasis in nucleus basalis of Meynert (NBM) and frontal cortex, the cholinergic enriched regions. We activated GSK-3 by lateral ventricular infusion of wortmannin (WT) and GF-109203X (GFX), the inhibitors of phosphoinositol-3 kinase (PI3-K) and protein kinase C (PKC), respectively, and significantly decreased the acetylcholine (ACh) level via inhibiting choline acetyl transferase (ChAT) rather than regulating acetylcholinesterase (AChE). Neuronal axonal transport was disrupted and ChAT accumulation occurred in NBM and frontal cortex accompanied with hyperphosphorylation of tau and neurofilaments. Moreover, ChAT expression decreased in NBM attributing to cleavage of nuclear factor-kappaB/p100 into p52 for translocation into nucleus to lower ChAT mRNA level. The cholinergic dysfunction could be mimicked by overexpression of GSK-3 and rescued by simultaneous administration of LiCl or SB216763, inhibitors of GSK-3. Our data reveal the molecular mechanism that may underlie the cholinergic impairments in AD patients.
Title: Fluorescence Resonance Energy Transfer-based Biosensor Composed of Nitrogen-doped Carbon Dots and Gold Nanoparticles for the Highly Sensitive Detection of Organophosphorus Pesticides Gong NC, Li YL, Jiang X, Zheng XF, Wang YY, Huan SY Ref: Anal Sci, 32:951, 2016 : PubMed
The present article reports a novel biosensor for organophosphorus pesticides based on fluorescence resonance energy transfer (FRET) between nitrogen-doped carbon dots (NC-dots) and gold nanoparticles (AuNPs). The effective NC-dots/AuNPs assembly through the Au-N interaction results in good fluorescence quenching. Active acetylcholinesterase (AChE) catalyzes the hydrolysis of acetylthiocholine into -SH containing thiocholine to replace the NC-dots and trigger the aggregation of AuNPs. In the presence of paraoxon, the activity of AChE is inhibited, and thus preventing the generation of thiocholine, causing fewer NC-dots to be replaced. As a consequence, the fluorescence intensity gradually decreases with increasing amount of paraoxon. This biosensor does not require any complex synthesis or modification, and the results show a wide detection range of from 10(-4) to 10(-9) g/L with a detection limit of 1.0 x 10(-9) g/L (3.6 x 10(-12) mol/L). Two linear response regions have been reported with a turning point at about 10(-6) g/L and three different factors that would influence the response behavior. These phenomena discussed in detail so as to explain the special response mechanism.
Post-stroke cognitive impairment (PSCI), commonly seen in the clinical practice, is a major factor impeding patient rehabilitation. Enriched environment (EE) intervention is a simple and effective way to improve cognitive impairment, partially due to the rebalancing of the basal forebrain-hippocampus cholinergic signaling pathway. Epigenetic changes have been identified in many cognitive disorders. However, studies on the effects of EE on epigenetic regulation of cholinergic circuits in PSCI animal models have not yet been reported. In this study, we established a photothrombotic mouse PSCI model and showed that after EE intervention, mice with PSCI had significantly improved water maze performance, better induction of hippocampal long-term potentiation (LTP), enhanced function of the basal forebrain-hippocampus cholinergic circuits of contralateral side of stroke and relatively balanced acetylation homeostasis compared to those of PSCI mice in standard environments (SE). In addition, PSCI mice in EE expressed much higher levels of p-CREB and CBP than in SE, and the chromatins bound to M-type promoter of ChAT gene were more acetylated. These results demonstrate that EE plays an important role in the improvement of PSCI and the underlying mechanism may involve in the acetylation of histones bound to the ChAT gene promoter in cholinergic circuits.
The large yellow croaker Larimichthys crocea (L. crocea) is one of the most economically important marine fish in China and East Asian countries. It also exhibits peculiar behavioral and physiological characteristics, especially sensitive to various environmental stresses, such as hypoxia and air exposure. These traits may render L. crocea a good model for investigating the response mechanisms to environmental stress. To understand the molecular and genetic mechanisms underlying the adaptation and response of L. crocea to environmental stress, we sequenced and assembled the genome of L. crocea using a bacterial artificial chromosome and whole-genome shotgun hierarchical strategy. The final genome assembly was 679 Mb, with a contig N50 of 63.11 kb and a scaffold N50 of 1.03 Mb, containing 25,401 protein-coding genes. Gene families underlying adaptive behaviours, such as vision-related crystallins, olfactory receptors, and auditory sense-related genes, were significantly expanded in the genome of L. crocea relative to those of other vertebrates. Transcriptome analyses of the hypoxia-exposed L. crocea brain revealed new aspects of neuro-endocrine-immune/metabolism regulatory networks that may help the fish to avoid cerebral inflammatory injury and maintain energy balance under hypoxia. Proteomics data demonstrate that skin mucus of the air-exposed L. crocea had a complex composition, with an unexpectedly high number of proteins (3,209), suggesting its multiple protective mechanisms involved in antioxidant functions, oxygen transport, immune defence, and osmotic and ionic regulation. Our results reveal the molecular and genetic basis of fish adaptation and response to hypoxia and air exposure. The data generated by this study will provide valuable resources for the genetic improvement of stress resistance and yield potential in L. crocea.
The Asian tiger mosquito, Aedes albopictus, is a highly successful invasive species that transmits a number of human viral diseases, including dengue and Chikungunya fevers. This species has a large genome with significant population-based size variation. The complete genome sequence was determined for the Foshan strain, an established laboratory colony derived from wild mosquitoes from southeastern China, a region within the historical range of the origin of the species. The genome comprises 1,967 Mb, the largest mosquito genome sequenced to date, and its size results principally from an abundance of repetitive DNA classes. In addition, expansions of the numbers of members in gene families involved in insecticide-resistance mechanisms, diapause, sex determination, immunity, and olfaction also contribute to the larger size. Portions of integrated flavivirus-like genomes support a shared evolutionary history of association of these viruses with their vector. The large genome repertory may contribute to the adaptability and success of Ae. albopictus as an invasive species.
Butterflies are exceptionally diverse but their potential as an experimental system has been limited by the difficulty of deciphering heterozygous genomes and a lack of genetic manipulation technology. Here we use a hybrid assembly approach to construct high-quality reference genomes for Papilio xuthus (contig and scaffold N50: 492 kb, 3.4 Mb) and Papilio machaon (contig and scaffold N50: 81 kb, 1.15 Mb), highly heterozygous species that differ in host plant affiliations, and adult and larval colour patterns. Integrating comparative genomics and analyses of gene expression yields multiple insights into butterfly evolution, including potential roles of specific genes in recent diversification. To functionally test gene function, we develop an efficient (up to 92.5%) CRISPR/Cas9 gene editing method that yields obvious phenotypes with three genes, Abdominal-B, ebony and frizzled. Our results provide valuable genomic and technological resources for butterflies and unlock their potential as a genetic model system.
Title: Preoperative risk factors for prolonged postoperative ventilation following thymectomy in myasthenia gravis Lu W, Yu T, Longhini F, Jiang X, Qin X, Jin X Ref: Int J Clin Exp Med, 8:13990, 2015 : PubMed
Adequate preoperative evaluation and preparation for surgery are required to prevent prolonged mechanical ventilation after thymectomy, and facilitate the recovery of patients with myasthenia gravis (MG). The objective of this study was to identify the preoperative risk factors for extubation failure after thymectomy in patients with MG. METHODS: A retrospective study was conducted on 61 patients with MG who underwent extended thymectomy. Several factors were evaluated including patients' demographic data, preoperative medical therapies, medical history, and comorbidities. Multivariate logistic regression analysis was used to identify the predictors of late extubation after thymectomy for MG. RESULTS: Fourteen patients (22.95%) required breathing support after anesthesia or endotracheal re-intubation within 48 h. Univariate analysis illustrated that the quantitative MG (QMG) grade (odds ratio [OR] = 1.368, P = 0.000), preoperative muscle strength (OR = 0.279, P = 0.000), use of pyridostigmine (OR = 1.011, P = 0.024) and prednisone (OR = 1.059, P = 0.022), preoperative lung function (OR = 4.875, P = 0.016), low preoperative cholinesterase levels (OR = 0.999, P = 0.014), impaired preoperative swallowing muscle activity (OR = 7.619, P = 0.003), and positivity for acetylcholine receptor antibodies (OR = 14.143, P = 0.001) were significant predictors of prolonged postoperative intubation. Multivariate logistic regression analysis revealed that the QMG score (OR = 3.408, P = 0.000) and Myasthenia Gravis Foundation of America (MGFA) classification (OR = 28.683, P = 0.002) were independent risk factors for prolonged postoperative intubation. CONCLUSION: The preoperative MGFA clinical classification and QMG score were independent risk factors for prolonged postoperative intubation in patients with MG.
Organophosphate poisoning is highly lethal as organophosphates, which are commonly found in insecticides and nerve agents, cause irreversible phosphorylation and inactivation of acetylcholinesterase (AChE), leading to neuromuscular disorders via accumulation of acetylcholine in the body. Direct interception of organophosphates in the systemic circulation thus provides a desirable strategy in treatment of the condition. Inspired by the presence of AChE on red blood cell (RBC) membranes, we explored a biomimetic nanoparticle consisting of a polymeric core surrounded by RBC membranes to serve as an anti-organophosphate agent. Through in vitro studies, we demonstrated that the biomimetic nanoparticles retain the enzymatic activity of membrane-bound AChE and are able to bind to a model organophosphate, dichlorvos, precluding its inhibitory effect on other enzymatic substrates. In a mouse model of organophosphate poisoning, the nanoparticles were shown to improve the AChE activity in the blood and markedly improved the survival of dichlorvos-challenged mice.
Although recent innovations in transient plant systems have enabled gram quantities of proteins in 1-2 weeks, very few have been translated into applications due to technical challenges and high downstream processing costs. Here we report high-level production, using a Nicotiana benthamiana/p19 system, of an engineered recombinant human acetylcholinesterase (rAChE) that is highly stable in a minimally processed leaf extract. Lyophylized clarified extracts withstand prolonged storage at 70 degrees C and, upon reconstitution, can be used in several devices to detect organophosphate (OP) nerve agents and pesticides on surfaces ranging from 0 degrees C to 50 degrees C. The recent use of sarin in Syria highlights the urgent need for nerve agent detection and countermeasures necessary for preparedness and emergency responses. Bypassing cumbersome and expensive downstream processes has enabled us to fully exploit the speed, low cost and scalability of transient production systems resulting in the first successful implementation of plant-produced rAChE into a commercial biotechnology product.
Title: Pharmacokinetics and immunogenicity of a recombinant human butyrylcholinesterase bioscavenger in macaques following intravenous and pulmonary delivery Rosenberg YJ, Adams RJ, Hernandez-Abanto S, Jiang X, Sun W, Mao L, Lee KD Ref: Chemico-Biological Interactions, 242:219, 2015 : PubMed
Recombinant (r) and native butyrylcholinesterse (BChE) are potent bioscavengers of organophosphates (OPs) such as nerve agents and pesticides and are undergoing development as antidotal treatments for OP-induced toxicity. Because of the lethal properties of such agents, regulatory approval will require extensive testing under the Animal Rule. However, human (Hu) glycoprotein biologicals, such as BChE, present a challenge for assessing immunogenicity and efficacy in heterologous animal models since any immune responses to the small species differences in amino acids or glycans between the host and biologic may alter pharmacodynamics and preclude accurate efficacy testing; possibly underestimating their potential protective value in humans. To establish accurate pharmacokinetic and efficacy data, an homologous animal model has been developed in which native and PEGylated forms of CHO-derived rMaBChE were multiply injected into homologous macaques with no induction of antibody. These now serve as controls for assessing the pharmacokinetics and immunogenicity in macaques of multiple administrations of PEGylated and unmodified human rBChE (rHuBChE) by both intravenous (IV) and pulmonary routes. The results indicate that, except for maximal concentration (Cmax), the pharmacokinetic parameters following IV injection with heterologous PEG-rHuBChE were greatly reduced even after the first injection compared with homologous PEG-rMaBChE. Anti-HuBChE antibody responses were induced in all monkeys after the second and third administrations regardless of the route of delivery; impacting rates of clearance and usually resulting in reduced endogenous MaBChE activity. These data highlight the difficulties inherent in assessing pharmacokinetics and immunogenicity in animal models, but bode well for the efficacy and safety of rHuBChE pretreatments in homologous humans.
Mycobacterium tuberculosis (Mtb) maintains its intrabacterial pH (pHIB) near neutrality in the acidic environment of phagosomes within activated macrophages. A previously reported genetic screen revealed that Mtb loses this ability when the mycobacterial acid resistance protease (marP) gene is disrupted. In the present study, a high throughput screen (HTS) of compounds against the protease domain of MarP identified benzoxazinones as inhibitors of MarP. A potent benzoxazinone, BO43 (6-chloro-2-(2'-methylphenyl)-4H-1,3-benzoxazin-4-one), acylated MarP and lowered Mtb's pHIB and survival during incubation at pH 4.5. BO43 had similar effects on MarP-deficient Mtb, suggesting the existence of additional target(s). Reaction of an alkynyl-benzoxazinone, BO43T, with Mycobacterium bovis variant bacille Calmette-Guerin (BCG) followed by click chemistry with azido-biotin identified both the MarP homologue and the high temperature requirement A1 (HtrA1) homologue, an essential protein. Thus, the chemical probe identified through a target-based screen not only reacted with its intended target in the intact cells but also implicated an additional enzyme that had eluded a genetic screen biased against essential genes.
PURPOSE: H102, a novel beta-sheet breaker peptide, was encapsulated into liposomes to reduce its degradation and increase its brain penetration through intranasal administration for the treatment of Alzheimer's disease (AD). METHODS: The H102 liposomes were prepared using a modified thin film hydration method, and their transport characteristics were tested on Calu-3 cell monolayers. The pharmacokinetics in rats' blood and brains were also investigated. Behavioral experiments were performed to evaluate the improvements on AD rats' spatial memory impairment. The neuroprotective effects were tested by detecting acetylcholinesterase (AchE), choline acetyltransferase (ChAT) and insulin degrading enzyme (IDE) activity and conducting histological assays. The safety was evaluated on rats' nasal mucosa and cilia. RESULTS: The liposomes prepared could penetrate Calu-3 cell monolayers consistently. After intranasal administration, H102 could be effectively delivered to the brain, and the AUC of H102 liposomes in the hippocampus was 2.92-fold larger than that of solution group. H102 liposomes could excellently ameliorate spatial memory impairment of AD model rats, increase the activities of ChAT and IDE and inhibit plaque deposition, even in a lower dosage compared with H102 intranasal solution. H102 nasal formulations showed no toxicity on nasal mucosa. CONCLUSIONS: The H102-loaded liposome prepared in this study for nasal administration is stable, effective and safe, which has great potential for AD treatment.
Title: Iterative type I polyketide synthases involved in enediyne natural product biosynthesis Chen X, Ji R, Jiang X, Yang R, Liu F, Xin Y Ref: IUBMB Life, 66:587, 2014 : PubMed
Enediyne natural products are potent antibiotics structurally characterized by an enediyne core containing two acetylenic groups conjugated to a double bond in a 9- or 10-membered carbocycle. The biosynthetic gene clusters for enediynes encode a novel iterative type I polyketide synthase (PKSE), which is generally believed to initiate the biosynthetic process of enediyne cores. This review article will cover research efforts made since its discovery to elucidate the role of the PKSE in enediyne core biosynthesis. Topics covered include the unique domain architecture, identification, and characterization of turnover products, and interaction with partner thioesterase protein.
BACKGROUND: The asexual fungus Fusarium oxysporum f. sp. cubense (Foc) causing vascular wilt disease is one of the most devastating pathogens of banana (Musa spp.). To understand the molecular underpinning of pathogenicity in Foc, the genomes and transcriptomes of two Foc isolates were sequenced. METHODOLOGY/PRINCIPAL FINDINGS: Genome analysis revealed that the genome structures of race 1 and race 4 isolates were highly syntenic with those of F. oxysporum f. sp. lycopersici strain Fol4287. A large number of putative virulence associated genes were identified in both Foc genomes, including genes putatively involved in root attachment, cell degradation, detoxification of toxin, transport, secondary metabolites biosynthesis and signal transductions. Importantly, relative to the Foc race 1 isolate (Foc1), the Foc race 4 isolate (Foc4) has evolved with some expanded gene families of transporters and transcription factors for transport of toxins and nutrients that may facilitate its ability to adapt to host environments and contribute to pathogenicity to banana. Transcriptome analysis disclosed a significant difference in transcriptional responses between Foc1 and Foc4 at 48 h post inoculation to the banana 'Brazil' in comparison with the vegetative growth stage. Of particular note, more virulence-associated genes were up regulated in Foc4 than in Foc1. Several signaling pathways like the mitogen-activated protein kinase Fmk1 mediated invasion growth pathway, the FGA1-mediated G protein signaling pathway and a pathogenicity associated two-component system were activated in Foc4 rather than in Foc1. Together, these differences in gene content and transcription response between Foc1 and Foc4 might account for variation in their virulence during infection of the banana variety 'Brazil'. CONCLUSIONS/SIGNIFICANCE: Foc genome sequences will facilitate us to identify pathogenicity mechanism involved in the banana vascular wilt disease development. These will thus advance us develop effective methods for managing the banana vascular wilt disease, including improvement of disease resistance in banana.
BACKGROUND: Anopheles stephensi is the key vector of malaria throughout the Indian subcontinent and Middle East and an emerging model for molecular and genetic studies of mosquito-parasite interactions. The type form of the species is responsible for the majority of urban malaria transmission across its range. RESULTS: Here, we report the genome sequence and annotation of the Indian strain of the type form of An. stephensi. The 221 Mb genome assembly represents more than 92% of the entire genome and was produced using a combination of 454, Illumina, and PacBio sequencing. Physical mapping assigned 62% of the genome onto chromosomes, enabling chromosome-based analysis. Comparisons between An. stephensi and An. gambiae reveal that the rate of gene order reshuffling on the X chromosome was three times higher than that on the autosomes. An. stephensi has more heterochromatin in pericentric regions but less repetitive DNA in chromosome arms than An. gambiae. We also identify a number of Y-chromosome contigs and BACs. Interspersed repeats constitute 7.1% of the assembled genome while LTR retrotransposons alone comprise more than 49% of the Y contigs. RNA-seq analyses provide new insights into mosquito innate immunity, development, and sexual dimorphism. CONCLUSIONS: The genome analysis described in this manuscript provides a resource and platform for fundamental and translational research into a major urban malaria vector. Chromosome-based investigations provide unique perspectives on Anopheles chromosome evolution. RNA-seq analysis and studies of immunity genes offer new insights into mosquito biology and mosquito-parasite interactions.
Title: Protection against paraoxon toxicity by an intravenous pretreatment with polyethylene-glycol-conjugated recombinant butyrylcholinesterase in macaques Rosenberg YJ, Gearhart J, Mao L, Jiang X, Hernandez-Abanto S Ref: Chemico-Biological Interactions, 210:20, 2014 : PubMed
Recombinant (r) butyrylcholinesterase (rBChE) produced in CHO cells is being developed as a prophylactic countermeasure against neurotoxicity resulting from exposure to organophosphates (OPs) in the form of pesticides and nerve agents. To evaluate the efficacy of a parenteral pretreatment, a PEGylated macaque (Ma) form of rBChE was administered into homologous animals to ensure good plasma retention without immunogenicity. Thus, macaques were administered PEG-rMaBChE at either 5 or 7mg/kg intravenously (i.v.) and exposed subcutaneously to 12mug/kg of the potent pesticide paraoxon (Px) at 1h or at 1 and 72h, respectively. Protection was measured by the ability of rBChE prophylaxis to prevent the inhibition of circulating acetylcholinesterase on red blood cells (RBC-AChE). In rBChE-pretreated animals, no inhibition of RBC-AChE activity after the first Px exposure and only a 10-20% reduction after the second exposure were observed as compared to a 75% RBC-AChE inhibition usually obtained without pretreatment. In addition, these studies raised other interesting issues. The lipophilic nature of Px, appears to result in early and transient inhibition of RBC-AChE as a result of transfer of OP bound to RBC even in BChE-pretreated animals. The protection by a single injection of rBChE against two administrations of Px represents the first example of protection by an i.v. rBChE pretreatment against a pesticide such as Px and bodes well for a parenteral rHuBChE pretreatment as an OP countermeasure in humans.
Title: Improvement of the activation of lipase from Candida rugosa following physical and chemical immobilization on modified mesoporous silica Wang C, Li Y, Zhou G, Jiang X, Xu Y, Bu Z Ref: Mater Sci Eng C Mater Biol Appl, 45:261, 2014 : PubMed
Lipase from Candida rugosa (CRL) was chemically and physically immobilized onto four types of rod-shaped mesoporous silica (RSMS). RSMS prepared using surfactant P123 and poly(ethylene glycol) as co-templates was functionalized with (3-aminopropyl)triethoxysilane (APTES) to obtain P-RSMS by post-synthesis grafting. Tetraethoxysilane was hydrothermally co-condensed with APTES to obtain C-RSMS. A two-step process using APTES and glutaraldehyde was also performed to obtain G-RSMS. The effects of modification methods (including post-synthesis grafting and co-condensation) and glutaraldehyde on the mesoscopic order, interplanar spacing d100, cell parameter a0, mesoporous structure, and wall thickness of RSMS were studied in detail. Results showed that all samples were mesoporous materials with 2D mesostructures (p6mm). Pore size and d100 decreased, whereas the wall thickness increased after different modifications. CRL was used as a model enzyme to determine the effect of physical and chemical adsorption on loading amount and enzymatic activity. The possible mechanism of CRL immobilization on G-RSMS by chemical adsorption was systematically investigated. The chemical immobilization of CRL on G-RSMS increased the loading amount, hydrolytic activity, thermal stability, and reusability. Moreover, immobilized CRL was employed to catalyze the resolution of 2-octanol by esterification with caprylic acid. The enantiomeric excess of 2-octanol was 45.8% when the reaction was catalyzed by G-RSMS-CRL and decreased to about 38%-39% using the physically immobilized CRL, after 48h of reaction in hexane.
Mudskippers are amphibious fishes that have developed morphological and physiological adaptations to match their unique lifestyles. Here we perform whole-genome sequencing of four representative mudskippers to elucidate the molecular mechanisms underlying these adaptations. We discover an expansion of innate immune system genes in the mudskippers that may provide defence against terrestrial pathogens. Several genes of the ammonia excretion pathway in the gills have experienced positive selection, suggesting their important roles in mudskippers' tolerance to environmental ammonia. Some vision-related genes are differentially lost or mutated, illustrating genomic changes associated with aerial vision. Transcriptomic analyses of mudskippers exposed to air highlight regulatory pathways that are up- or down-regulated in response to hypoxia. The present study provides a valuable resource for understanding the molecular mechanisms underlying water-to-land transition of vertebrates.
INTRODUCTION: A significant number of mania patients fail to respond to current pharmacotherapy, thereby there is need for novel augmentation strategies. The results of some early studies showed the effectiveness of cholinomimetics in the treatment of mania. One open case series suggested the efficacy of donepezil in the treatment of bipolar disorder. Our aim was to explore whether an oral cholinesterase inhibitor, donepezil, administered during a 4-week treatment period, would benefit patients with acute mania. METHODS: We conducted a 4-week double-blind, placebo-controlled trial of donepezil as an adjunctive treatment to lithium in patients with acute mania. Eligible subjects were randomly assigned to receive donepezil or placebo in addition to lithium. Donepezil was started at 5 mg/day, and increased to 10 mg/day in the first week. Patients were rated with the Young Mania Rating Scale (YMRS) and Brief Psychiatric Rating Scale (BPRS) at baseline, day 1, week 1, week 2, and week 4. RESULTS: Out of the 30 patients who were enrolled, 15 were on donepezil and 15 were on placebo. All patients completed the 4-week trial. On the first day, there was a difference of 1.97 units on the psychomotor symptoms scale of the YMRS in the donepezil group as compared to the placebo group (t = 2.39, P = 0.02). There was a difference of 0.57 units (t = 2.09, P = 0.04) in the speech item and a difference of 0.29 units in the sexual interest item (t = 2.11, P = 0.04) in the donepezil group as compared to the placebo group. The total YMRS difference on the first day approached the conventional significance level (1.97 units, t = 1.84, P = 0.07). Over the course of 4 weeks, we failed to find that donepezil produced any significant difference in the YMRS (6.71 units difference, t = -1.44, P = 0.16) or the BPRS scale (1.29 units difference, t = -0.33, P = 0.75) as compared to placebo. Ten subjects (66.67%) in both groups met the criteria for clinical response (Fisher's exact P = 1.00). Five subjects (33.33%) in the donepezil group met the criteria for clinical remission while nine subjects (60.00%) in the placebo group met the remission criteria (Fisher's exact P = 0.27). CONCLUSION: Use of the oral anticholinergic donepezil had some benefit in the augmentation of lithium treatment on the first day, but did not provide any significant benefits in the long-term.
Title: Highly sensitive colorimetric detection of organophosphate pesticides using copper catalyzed click chemistry Fu G, Chen W, Yue X, Jiang X Ref: Talanta, 103:110, 2013 : PubMed
Highly sensitive colorimetric detection of organophosphate pesticides (OPs) was developed using Cu (I)-catalyzed click chemistry as the colorimetric signal amplification process between the acetylcholine esterase-acetylthiocholine system (AChE-ATCl) and azide- terminal alkyne-functionalized Au NPs as the colorimetric probe. It was demonstrated that the involvement of Cu (I)-catalyzed click chemistry allowed greatly improved colorimetric sensitivity for OPs detection based on the indirect modulation of click chemistry-induced Au NPs aggregation by the AChE-ATCl system. Paraoxon as the model OPs in the concentration range from 10(-6) to 10(-4)g/L can be directly detected using the naked-eye-based colorimetric assay without the aid of any complex instruments. The results for paraoxon detection in spiked apple juice were found to be in good agreement with that obtained by the conventional UV-vis spectroscopy. This simple and reliable assay would greatly improve the public safety and environmental protection in an on-site and real-time detection format.
Development of effective non-invasive drug delivery systems is of great importance to the treatment of Alzheimer's diseases and has made great progress in recent years. In this work, lactoferrin (Lf), a natural iron binding protein, whose receptor is highly expressed in both respiratory epithelial cells and neurons is here utilized to facilitate the nose-to-brain drug delivery of neuroprotection peptides. The Lf-conjugated PEG-PCL nanoparticle (Lf-NP) was constructed via a maleimide-thiol reaction with the Lf conjugation confirmed by CBQCA Protein Quantitation and XPS analysis. Other important parameters such as particle size distribution, zeta potential and in vitro release of fluorescent probes were also characterized. Compared with unmodified nanoparticles (NP), Lf-NP exhibited a significantly enhanced cellular accumulation in 16HBE14o-cells through both caveolae-/clathrin-mediated endocytosis and direct translocation. Following intranasal administration, Lf-NP facilitated the brain distribution of the coumarin-6 incorporated with the AUC0-8h in rat cerebrum (with hippocampus removed), cerebellum, olfactory tract, olfactory bulb and hippocampus 1.36, 1.53, 1.70, 1.57 and 1.23 times higher than that of coumarin-6 carried by NP, respectively. Using a neuroprotective peptide - NAPVSIPQ (NAP) as the model drug, the neuroprotective and memory improvement effect of Lf-NP was observed even at lower dose than that of NP in a Morris water maze experiment, which was also confirmed by the evaluation of acetylcholinesterase, choline acetyltransferase activity and neuronal degeneration in the mice hippocampus. In conclusion, Lf-NP may serve as a promising nose-to-brain drug delivery carrier especially for peptides and proteins.
Title: Pulmonary delivery of an aerosolized recombinant human butyrylcholinesterase pretreatment protects against aerosolized paraoxon in macaques Rosenberg YJ, Laube B, Mao L, Jiang X, Hernandez-Abanto S, Lee KD, Adams R Ref: Chemico-Biological Interactions, 203:167, 2013 : PubMed
Butyrylcholinesterase (BChE) is the leading pretreatment candidate against exposure to organophosphates (OPs), which pose an ever increasing public and military health. Since respiratory failure is the primary cause of death following acute OP poisoning, an inhaled BChE therapeutic could prove highly efficacious in preventing acute toxicity as well as the associated delayed neuropathy. To address this, studies have been performed in mice and macaques using Chinese Hamster Ovary cells (CHO)-derived recombinant (r) BChE delivered by the pulmonary route, to examine whether the deposition of both macaque (Ma) and human (Hu) rBChE administered as aerosols (aer) favored the creation and retention of an efficient protective "pulmonary bioshield" that could scavenge incoming (inhaled) OPs in situ thereby preventing entry into the circulation and inhibition of plasma BChE and AChE on red blood cells (RBC-AChE) and in cholinergic synapses. In contrast to parenteral delivery of rBChE, which currently requires posttranslational modification for good plasma stability, an unmodified aer-rBChE pretreatment given 1-40h prior to >1 LD50 of aer-paraoxon (Px) was able to prevent inhibition of circulating cholinesterase in a dose-dependent manner. These studies are the first to show protection by rBChE against a pesticide such as paraoxon when delivered directly into the lung and bode well for the use of a non-invasive and consumer friendly method of rHuBChE delivery as a human treatment to counteract OP toxicity.
Title: Cloning, expression and characterization of a new enantioselective esterase from a marine bacterium Pelagibacterium halotolerans B2T Wei X, Jiang X, Ye L, Yuan S, Chen Z, Wu M, Yu H Ref: J Mol Catal B Enzym, 97:270, 2013 : PubMed
An esterase, designated as PE8 (219 aa, 23.19 kDa), was cloned from a marine bacterium Pelagibacterium halotolerans B2T and overexpressed in Escherichia coli Rosetta, resulting an active, soluble protein which constituted 23.1% of the total cell protein content. Phylogenetic analysis of the protein showed it was a new member of family VI lipolytic enzymes. Biochemical characterization analysis showed that PE8 preferred short chain p-nitrophenyl esters (C2-C6), exhibited maximum activity toward p-nitrophenyl acetate, and was not a metalloenzyme. PE8 was an alkaline esterase with an optimal pH of 9.5 and an optimal temperature of 45 C toward p-nitrophenyl acetate. Furthermore, it was found that PE8 exhibited activity and enantioselectivity in the synthesis of methyl (R)-3-(4-fluorophenyl)glutarate ((R)-3-MFG) from the prochiral dimethyl 3-(4-fluorophenyl)glutarate (3-DFG). (R)-3-MFG was obtained in 71.6% ee and 73.2% yield after 36 h reaction under optimized conditions (0.6 M phosphate buffer (pH 8.0) containing 17.5% 1,4-dioxane under 30C). In addition, PE8 was tolerant to extremely strong basic and high ionic strength solutions as it exhibited high activity even at pH 11.0 in 1 M phosphate buffer. Given its highly soluble expression, alkalitolerance, halotolerance and enantioselectivity, PE8 could be a promising candidate for the production of (R)-3-MFG in industry. The results also demonstrate the potential of the marine environment as a source of useful biocatalysts.
Bats are the only mammals capable of sustained flight and are notorious reservoir hosts for some of the world's most highly pathogenic viruses, including Nipah, Hendra, Ebola, and severe acute respiratory syndrome (SARS). To identify genetic changes associated with the development of bat-specific traits, we performed whole-genome sequencing and comparative analyses of two distantly related species, fruit bat Pteropus alecto and insectivorous bat Myotis davidii. We discovered an unexpected concentration of positively selected genes in the DNA damage checkpoint and nuclear factor kappaB pathways that may be related to the origin of flight, as well as expansion and contraction of important gene families. Comparison of bat genomes with other mammalian species has provided new insights into bat biology and evolution.
Title: Enhancement of nose-to-brain delivery of basic fibroblast growth factor for improving rat memory impairments induced by co-injection of beta-amyloid and ibotenic acid into the bilateral hippocampus Feng C, Zhang C, Shao X, Liu Q, Qian Y, Feng L, Chen J, Zha Y, Zhang Q, Jiang X Ref: Int J Pharm, 423:226, 2012 : PubMed
Basic fibroblast growth factor (bFGF) delivery to the brain of animals appears to be an emerging potential therapeutic approach to neurodegenerative diseases, such as Alzheimer's disease (AD). The intranasal route of administration could provide an alternative to intracerebroventricular infusion. A nasal spray of bFGF had been developed previously and the objective of the present study was to investigate whether bFGF nasal spray could enhance brain uptake of bFGF and ameliorate memory impairment induced by co-injection of beta-amyloid(25-35) and ibotenic acid into bilateral hippocampus of rats. The results of brain uptake study showed that the AUC(0-12h) of bFGF nasal spray in olfactory bulb, cerebrum, cerebellum and hippocampus was respectively 2.47, 2.38, 2.56 and 2.19 times that of intravenous bFGF solution, and 1.11, 1.95, 1.40 and 1.93 times that of intranasal bFGF solution, indicating that intranasal administration of bFGF nasal spray was an effective means of delivering bFGF to the brain, especially to cerebrum and hippocampus. In Morris water maze tasks, intravenous administration of bFGF solution at high dose (40 mug/kg) showed little improvement on spatial memory impairment. In contrast, bFGF solution of the same dose following intranasal administration could significantly ameliorate spatial memory impairment. bFGF nasal spray obviously improved spatial memory impairment even at a dose half (20 mug/kg) of bFGF solution, recovered their acetylcholinesterase and choline acetyltransferase activity to the sham control level, and alleviated neuronal degeneration in rat hippocampus, indicating neuroprotective effects on the central nerve system. In a word, bFGF nasal spray may be a new formulation of great potential for treating AD.
Title: Identification and characterization of novel esterases from a deep-sea sediment metagenome Jiang X, Xu X, Huo Y, Wu Y, Zhu X, Zhang X, Wu M Ref: Arch Microbiol, 194:207, 2012 : PubMed
A deep-sea sediment metagenomic library was constructed and screened for lipolytic enzymes by activity-based approach. Nine novel lipolytic enzymes were identified, and the amino acid sequences shared 56% to 84% identity to other lipolytic enzymes in the database. Phylogenetic analysis showed that these enzymes belonged to family IV lipolytic enzymes. One of the lipolytic enzymes, Est6, was successfully cloned and expressed in Escherichia coli Rosetta in a soluble form. The recombinant protein was purified by Ni-nitrilotriacetic affinity chromatography column and characterized using p-nitrophenyl esters with various chain lengths. The est6 gene consisted of 909 bp that encoded 302 amino acid residues. Est6 was most similar to a lipolytic enzyme from uncultured bacterium (ACL67845, 61% identity) isolated from the South China Sea marine sediment metagenome. The characterization of Est6 revealed that it was a cold-active esterase and exhibited the highest activity toward p-nitrophenyl butyrate (C4) at 20 degrees C and pH 7.5.
Title: Cloning, expression and characterization of a halotolerant esterase from a marine bacterium Pelagibacterium halotolerans B2T Jiang X, Huo Y, Cheng H, Zhang X, Zhu X, Wu M Ref: Extremophiles, 16:427, 2012 : PubMed
An esterase PE10 (279 aa) from Pelagibacterium halotolerans B2(T) was cloned and overexpressed in Escherichia coli Rosetta in a soluble form. The deduced protein was 29.91 kDa and the phylogenetic analysis of the deduced amino acids sequence showed it represented a new family of lipolytic enzymes. The recombinant protein was purified by Ni-NTA affinity chromatography column and the characterization showed its optimal temperature and pH were 45 degrees C and pH 7.5, respectively. Substrate specificity study showed PE10 preferred short chain p-nitrophenyl esters and exhibited maximum activity toward p-nitrophenyl acetate. In addition, PE10 was a halotolerant esterase as it was still active under 4 M NaCl. Three-dimensional modeling of PE10 suggested that the high negative electrostatic potential on the surface may relevant to its tolerance to high salt environment. With this halotolerance property, PE10 could be a candidate for industrial use.
Title: Biosynthesis and properties of medium-chain-length polyhydroxyalkanoates with enriched content of the dominant monomer Jiang X, Sun Z, Marchessault RH, Ramsay JA, Ramsay BA Ref: Biomacromolecules, 13:2926, 2012 : PubMed
When grown in a nonanoic acid-limited chemostat at a dilution rate of 0.25 h(-1), Pseudomonas putida KT2440 produced poly(3-hydroxynonanoate-co-3-hydroxyheptanoate) containing 68 mol % 3-hydroxynonanoate (C9) and 32 mol % 3-hydroxyheptanoate (C7). Under the same conditions, but in the presence of acrylic acid, a fatty acid beta-oxidation inhibitor, the C9 monomer content increased to 88 mol %. Cofeeding glucose (3.9 g L(-1)) and nonanoic acid (2.9 +/- 0.1 g L(-1)) in continuous culture with 0.2 g L(-1) of acrylic acid in the feed, further increased the C9 content to 95 mol %. A yield of PHA from nonanoic acid of 0.93 mol mol(-1) was attained. PHA with a 3-hydroxyoctanoate (C8) content of 98 mol % was produced with the same cofeeding methodology from octanoic acid. As the dominant monomer content increased, the melting point of the poly(3-hydroxynonanoate) copolymers increased from 46 to 63 degreesC and that of the poly(3-hydroxyoctanoate) copolymers from 54 to 62 degreesC. All copolymer compositions resulted in elongation to break values of about 1300%, but tensile strength at break and Young's modulus both increased with increasing amounts of the dominant monomer.
Title: A highly sensitive gold-nanoparticle-based assay for acetylcholinesterase in cerebrospinal fluid of transgenic mice with Alzheimer's disease Liu D, Chen W, Tian Y, He S, Zheng W, Sun J, Wang Z, Jiang X Ref: Adv Healthc Mater, 1:90, 2012 : PubMed
A highly sensitive, selective, and dual-readout (colorimetric and fluorometric) assay for acetylcholinesterase (AChE) based on Rhodamine B-modified gold nanoparticle is reported. Due to its good sensitivity and selectivity, the assay can be used for monitoring AChE levels in the cerebrospinal fluid of transgenic mice with Alzheimer's disease.
Title: Complete genome sequence of Klebsiella pneumoniae subsp. pneumoniae HS11286, a multidrug-resistant strain isolated from human sputum Liu P, Li P, Jiang X, Bi D, Xie Y, Tai C, Deng Z, Rajakumar K, Ou HY Ref: Journal of Bacteriology, 194:1841, 2012 : PubMed
Klebsiella pneumoniae is an important pathogen commonly associated with opportunistic infections. Here we report the genome sequence of a strain, HS11286, isolated from human sputum in 2011 in Shanghai, China. It contains one chromosome (5.3 Mb), three multidrug resistance plasmids ( approximately 110 kb), including a carbapenemase producer, and three small plasmids ( approximately 3 kb).
Title: A highly sensitive, dual-readout assay based on gold nanoparticles for organophosphorus and carbamate pesticides Liu D, Chen W, Wei J, Li X, Wang Z, Jiang X Ref: Analytical Chemistry, 84:4185, 2012 : PubMed
This report presents a highly sensitive, rhodamine B-covered gold nanoparticle (RB-AuNP) -based assay with dual readouts (colorimetric and fluorometric) for detecting organophosphorus and carbamate pesticides in complex solutions. The detection mechanism is based on the fact that these pesticides can inhibit the activity of acetylcholinesterase (AChE), thus preventing the generation of thiocholine (which turns the RB-AuNP solutions blue and unquenches the fluorescence of RB simultaneously). The color of the RB-AuNP solution remains red and the fluorescence of RB remains quenched. By use of this dual-readout assay, the lowest detectable concentrations for several kinds of pesticides including carbaryl, diazinon, malathion, and phorate were measured to be 0.1, 0.1, 0.3, and 1 mug/L, respectively, all of which are much lower than the maximum residue limits (MRL) as reported in the European Union pesticides database as well as those from the U.S. Department Agriculture (USDA). This assay allows detection of pesticides in real samples such as agricultural products and river water. The results in detecting pesticide residues collected from food samples via this method agree well with those from high-performance liquid chromatography (HPLC). This simple assay is therefore suitable for sensing pesticides in complex samples, especially in combination with other portable platforms.
Paenibacillus mucilaginosus is a ubiquitous functional bacterium in microbial fertilizer. Here we report the complete sequence of P. mucilaginosus 3016. Multiple sets of functional genes have been found in the genome. To the best of our knowledge, this is the first announcement about the complete genome sequence of a P. mucilaginosus strain.
Title: A novel small Odorranalectin-bearing cubosomes: preparation, brain delivery and pharmacodynamic study on amyloid-beta(2)(5)(-)(3)(5)-treated rats following intranasal administration Wu H, Li J, Zhang Q, Yan X, Guo L, Gao X, Qiu M, Jiang X, Lai R, Chen H Ref: Eur J Pharm Biopharm, 80:368, 2012 : PubMed
Because of the immunogenicity and toxicity in vivo of large molecules such as lectins, the application of these molecules is remarkably restricted in drug delivery systems. In this study, to improve the brain drug delivery and reduce the immunogenicity of traditional lectin modified delivery system, Odorranalectin (OL, 1700 Da), a novel non-immunogenic small peptide, was selected to establish an OL-modified cubosomes (Cubs) system. The streptavidin (SA)-conjugated Cubs were prepared by incorporating maleimide-PEG-oleate and taking advantage of its thiol group binding reactivity to conjugate with 2-iminothiolane thiolated SA; mono-biotinylated OL was then coupled with the SA-modified Cubs. The OL-decorated Cubs (OL-Cubs) devised via a non-covalent SA-biotin "bridge" made it easy to conjugate OL and determine the number of ligands on the surface of the Cubs using sensitive chemiluminescent detection. Retention of the bio-recognitive activity of OL after covalent coupling was verified by hemagglutination testing. Nose-to-brain delivery characteristic of OL-Cubs was investigated by in vivo fluorescent biodistribution using coumarin-6 as a marker. The relative uptake of coumarin carried by OL-Cubs was 1.66- to 3.46-fold in brain tissues compared to that incorporated in the Cubs. Besides, Gly14-Humanin (S14G-HN) as a model peptide drug was loaded into cubosomes and evaluated for its pharmacodynamics on Alzheimer's disease (AD) rats following intranasal administration by Morris water maze test and acetylcholinesterase activity determination. The results suggested that OL functionalization enhanced the therapeutic effects of S14G-HN-loaded cubosomes on AD. Thus, OL-Cubs might offer a novel effective and noninvasive system for brain drug delivery, especially for peptides and proteins.
The Pacific oyster Crassostrea gigas belongs to one of the most species-rich but genomically poorly explored phyla, the Mollusca. Here we report the sequencing and assembly of the oyster genome using short reads and a fosmid-pooling strategy, along with transcriptomes of development and stress response and the proteome of the shell. The oyster genome is highly polymorphic and rich in repetitive sequences, with some transposable elements still actively shaping variation. Transcriptome studies reveal an extensive set of genes responding to environmental stress. The expansion of genes coding for heat shock protein 70 and inhibitors of apoptosis is probably central to the oyster's adaptation to sessile life in the highly stressful intertidal zone. Our analyses also show that shell formation in molluscs is more complex than currently understood and involves extensive participation of cells and their exosomes. The oyster genome sequence fills a void in our understanding of the Lophotrochozoa.
Title: In vivo toxicity and immunogenicity of wheat germ agglutinin conjugated poly(ethylene glycol)-poly(lactic acid) nanoparticles for intranasal delivery to the brain Liu Q, Shao X, Chen J, Shen Y, Feng C, Gao X, Zhao Y, Li J, Zhang Q, Jiang X Ref: Toxicol Appl Pharmacol, 251:79, 2011 : PubMed
Biodegradable polymer-based nanoparticles have been widely studied to deliver therapeutic agents to the brain after intranasal administration. However, knowledge as to the side effects of nanoparticle delivery system to the brain is limited. The aim of this study was to investigate the in vivo toxicity and immunogenicity of wheat germ agglutinin (WGA) conjugated poly(ethylene glycol)-poly(lactic acid) nanoparticles (WGA-NP) after intranasal instillation. Sprague-Dawley rats were intranasally given WGA-NP for 7 continuous days. Amino acid neurotransmitters, lactate dehydrogenase (LDH) activity, reduced glutathione (GSH), acetylcholine, acetylcholinesterase activity, tumor necrosis factor alpha (TNF-alpha) and interleukin-8 (IL-8) in rat olfactory bulb (OB) and brain were measured to estimate the in vivo toxicity of WGA-NP. Balb/C mice were intranasally immunized by WGA-NP and then WGA-specific antibodies in serum and nasal wash were detected by indirect ELISA. WGA-NP showed slight toxicity to brain tissue, as evidenced by increased glutamate level in rat brain and enhanced LDH activity in rat OB. No significant changes in acetylcholine level, acetylcholinesterase activity, GSH level, TNF-alpha level and IL-8 level were observed in rat OB and brain for the WGA-NP group. WGA-specific antibodies in mice serum and nasal wash were not increased after two intranasal immunizations of WGA-NP. These results demonstrate that WGA-NP is a safe carrier system for intranasal delivery of therapeutic agents to the brain.
Paenibacillus polymyxa SC2 is an important plant growth-promoting rhizobacterium (PGPR). Here, we report the complete genome sequence of P. polymyxa SC2. Multiple sets of functional genes have been found in the genome. As far as we know, this is the first complete genome sequence of Paenibacillus polymyxa.
Title: Demonstration of in vivo stability and lack of immunogenicity of a polyethyleneglycol-conjugated recombinant CHO-derived butyrylcholinesterase bioscavenger using a homologous macaque model Rosenberg YJ, Saxena A, Sun W, Jiang X, Chilukuri N, Luo C, Doctor BP, Lee KD Ref: Chemico-Biological Interactions, 187:279, 2010 : PubMed
Human serum and recombinant butyrylcholinesterase (rHuBChE) are the most advanced prophylactics against organophosphate (OP) toxicity due to nerve agent or insecticide exposure. For ethical reasons, such potential multi-use treatments cannot be tested in humans and will require extensive testing in animal models and the "Animal Rule" 21 (21 CFR 601.90) for regulatory approval. This will involve multiple injections of rHuBChE into heterologous animals, e.g. macaques, rodents with inevitable immunogenicity and subsequent elimination of the enzyme on repeat injections. In order to accurately assess pharmacokinetics, efficacy and safety of a candidate rBChE in an "antibody free" system, a homologous macaque (Ma) model has been developed. In these studies, macaques received single or multiple intravenous injections of native MaBChE as well as unmodified or PEG-conjugated forms of rMaBChE produced in CHO cells. Compared to the poor plasma retention of unmodified rBChE (MRT: <10h), three injections of 1.5-2.3mg/kg of PEG-conjugated tetrameric rBChE resulted in high circulatory stability (MRT: >134h) and lack of immunogenicity similar to native MaBChE. PEG-conjugation of the monomeric rMaBChE form also exhibited pharmacokinetic profiles comparable to the tetrameric form (MRT: >113h). However, despite the increased bioavailability of PEG-rBChE, antigenicity studies using sandwich ELISA showed that while macaque BChE was not immunogenic in macaques, PEGylation of rMaBChE did not prevent binding to anti-BChE antibodies, suggesting PEGylation may not be sufficient to mask non-human epitopes on rBChE. This homologous model can provide necessary preclinical protection data for the use of PEG-rHuBChE in humans and bodes well for a safe and efficacious CHO-derived rHuBChE therapeutic.
Title: Cloning of a novel lipase gene, lipJ08, from Candida rugosa and expression in Pichia pastoris by codon optimization Xu L, Jiang X, Yang J, Liu Y, Yan Y Ref: Biotechnol Lett, 32:269, 2010 : PubMed
A novel lipase gene, lipJ08, was cloned from Candida rugosa ATCC14830, along with the already reported five lipase genes (lip1-lip5). Nucleotide sequencing indicated that the lipJ08 gene contains a 1650 bp open reading frame (ORF) without introns. The deduced amino acid sequence corresponds to 534 amino acid residues, including a putative signal sequence of 15 amino acid residues. Seventeen of the non-universal serine codons (CTG) of lipJ08 were converted into universal serine codons (TCT) by PCR-based mutagenesis. The native and codon-optimized lipJ08 genes were expressed in Pichia pastoris. The hydrolytic activity of the recombinant LIPJ08 was 4.7 U/ml, whereas the activity of the recombinant wild-type lipase could not be detected.
Human paraoxonase (HuPON1) is a serum enzyme that exhibits a broad spectrum of hydrolytic activities, including the hydrolysis of various organophosphates, esters, and recently identified lactone substrates. Despite intensive site-directed mutagenesis and other biological studies, the structural basis for the specificity of substrate interactions of HuPON1 remains elusive. In this study, we apply homology modeling, docking, and molecular dynamic (MD) simulations to probe the binding interactions of HuPON1 with representative substrates. The results suggest that the active site of HuPON1 is characterized by two distinct binding regions: the hydrophobic binding site for arylesters/lactones, and the paraoxon binding site for phosphotriesters. The unique binding modes proposed for each type of substrate reveal a number of key residues governing substrate specificity. The polymorphic residue R/Q192 interacts with the leaving group of paraoxon, suggesting it plays an important role in the proper positioning of this substrate in the active site. MD simulations of the optimal binding complexes show that residue Y71 undergoes an "open-closed" conformational change upon ligand binding, and forms strong interactions with substrates. Further binding free energy calculations and residual decomposition give a more refined molecular view of the energetics and origin of HuPON1/substrate interactions. These studies provide a theoretical model of substrate binding and specificity associated with wild type and mutant forms of HuPON1, which can be applied in the rational design of HuPON1 variants as bioscavengers with enhanced catalytic activity.
Title: Mutation in acetylcholinesterase1 associated with triazophos resistance in rice stem borer, Chilo suppressalis (Lepidoptera: Pyralidae) Jiang X, Qu M, Denholm I, Fang J, Jiang W, Han Z Ref: Biochemical & Biophysical Research Communications, 378:269, 2009 : PubMed
Two full-length genes encoding different acetylcholinesterases (AChEs), designated as Ch-ace1 and Ch-ace2, were cloned from strains of the rice stem borer (Chilo suppressalis) susceptible and resistant to the organophosphate insecticide triazophos. Sequence analysis found an amino acid mutation A314S in Ch-ace1 (corresponding to A201 in Torpedo californica AChE) that was consistently associated with the occurrence of resistance. This mutation removed an MspA1 I restriction site from the wild type allele. An assay based on restriction fragment length polymorphism (RFLP) analysis was developed to diagnose A314S genotypes in field populations. Results showed a strong correlation between frequencies of the mutation and phenotypic levels of resistance to triazophos. The assay offers a prospect for rapid monitoring of resistance and assisting with the appropriate choice of insecticide for combating damage caused by C. suppressalis.
PURPOSE: This Food and Drug Administration (FDA) approval report describes the data and analyses leading to the approval by the FDA of nilotinib (Tasigna, AMN-107; Novartis Pharmaceuticals Corporation), an inhibitor of Bcr-Abl tyrosine kinase, for the treatment of chronic-phase (CP) and accelerated-phase (AP) chronic myelogenous leukemia (CML) resistant to or intolerant of imatinib. EXPERIMENTAL DESIGN: The FDA approval of the efficacy and safety of nilotinib was based on the results of an ongoing single-arm, open-label, phase 2 clinical trial. The primary end point for CML-CP was unconfirmed major cytogenetic response. The efficacy end point for CML-AP was confirmed hematologic response. RESULTS: The major cytogenetic response rate in 232 evaluable CP patients was 40% (95% confidence interval, 33%, 46%). The hematologic response rate in 105 evaluable AP patients was 26% (95% confidence interval, 18%, 35%). The median duration of response has not been reached for both CML-CP and CML-AP responding patients. In CML-CP patients, the common serious drug-related adverse reactions were thrombocytopenia and neutropenia. In CML-AP patients, the common serious drug-related adverse reactions were thrombocytopenia, neutropenia, pneumonia, febrile neutropenia, leukopenia, intracranial hemorrhage, elevated lipase, and pyrexia. Nilotinib prolongs the QT interval and sudden deaths have been reported; these risks and appropriate risk minimization strategies are described in a boxed warning on the labeling. CONCLUSIONS: On October 29, 2007, the U.S. FDA granted accelerated approval to nilotinib (Tasigna) for use in the treatment of CP and AP Philadelphia chromosome positive CML in adult patients resistant to or intolerant of prior therapy that included imatinib.
Clear cell renal cell carcinoma (CCRCC) is the most common pathological type of renal cell carcinoma and the main cause of renal carcinoma mortality. NDRG2, a new member of the N-Myc downstream-regulated gene (NDRG) family, is a focus for study at present. Up to now, its expression and function in carcinoma remain unclear. The aim of this study was to investigate its expression in CCRCC tissues and several renal carcinoma cell lines. The expression of NDRG2 was evaluated in renal cell carcinoma cell lines, tumor and adjacent non-tumor tissues from same clear cell renal cell carcinoma patients, by using immunohistochemistry, immunofluorescence, RT-PCR and Western blot. By immunohistochemistry and immunofluorescence we found that NDRG2 was predominantly located in the cytoplasm and membrane of renal carcinoma cancer cells, and the positive rate of NDRG2 in renal carcinoma specimens was 30.3% (40/132), which is significantly lower than 91.67% (121/132) in normal renal tissues (p<0.01). The average staining score in normal renal tissues was significantly higher than renal carcinoma (6.12+/-1.84 versus 2.65+/-1.23, p<0.01). Moreover, NDRG2 mRNA and protein were down-regulated in 6 fresh CCRCC tissues compared with their adjacent noncancerous tissues and normal tissues. Its expression was also lower in the human CCRCC-derived cell lines A-498 and 786-O than in the human proximal tubular cell lines HK-2 and HKC. These results indicated that NDRG2 might play an important role in the carcinogenesis and development of CCRCC and may function as a tumor suppressor in CCRCC.
Title: Crystal structure of homoserine O-acetyltransferase from Leptospira interrogans Wang M, Liu L, Wang Y, Wei Z, Zhang P, Li Y, Jiang X, Xu H, Gong W Ref: Biochemical & Biophysical Research Communications, 363:1050, 2007 : PubMed
Homoserine O-acetyltransferase (HTA, EC 2.3.1.31) initiates methionine biosynthesis pathway by catalyzing the transfer of acetyl group from acetyl-CoA to homoserine. This study reports the crystal structure of HTA from Leptospira interrogans determined at 2.2A resolution using selenomethionyl single-wavelength anomalous diffraction method. HTA is modular and consists of two structurally distinct domains--a core alpha/beta domain containing the catalytic site and a helical bundle called the lid domain. Overall, the structure fold belongs to alpha/beta hydrolase superfamily with the characteristic 'catalytic triad' residues in the active site. Detailed structure analysis showed that the catalytic histidine and serine are both present in two conformations, which may be involved in the catalytic mechanism for acetyl transfer.
Some 23 analogues of the potent acetylcholinesterase (AChE) inhibitor territrem B (1) were designed, synthesized, and tested for their biological activities. Some of the new synthetic derivatives exhibited IC50 values for AChE inhibition in the upper micromolar range. Molecular-modeling studies indicated that a planar conformation seems to be crucial for AChE inhibition. The two N-atoms of the piperazine moieties in 5o, 5p, and 5r might further enhance the inhibitory effects. The cytotoxicities of selected compounds against six human tumor cell lines were also determined.
Title: Differences in active-site gorge dimensions of cholinesterases revealed by binding of inhibitors to human butyrylcholinesterase Saxena A, Redman AM, Jiang X, Lockridge O, Doctor BP Ref: Chemico-Biological Interactions, 119-120:61, 1999 : PubMed
We examined the role of A328(F330) in the binding of various inhibitors to cholinesterases (ChEs) using human butyrylcholinesterase (BChE) mutants to determine if the conclusions drawn from studies with acetylcholinesterase (AChE) mutants could be extended to BChE. For huperzine A and edrophonium, the results obtained with AChE mutants could be directly correlated with those obtained with native ChEs and site-specific mutants of human BChE. Inhibition studies of ethopropazine with BChE mutants, where A328 was modified to either F or Y, suggested that A328 was not solely responsible for the selectivity of ethopropazine. Volume calculations for the active-site gorge showed that the poor inhibitory activity of ethopropazine towards AChE was due to the smaller dimension of the active-site gorge. The volume of the BChE active-site gorge is approximately 200 A3 larger than that of the AChE gorge, which allows the accommodation of ethopropazine in two different orientations as demonstrated by rigid-body refinement and molecular dynamics calculations. These results suggest that, although the overall scaffolding of the two enzymes may be highly similar, the dimensions and the micro-environment of the gorge play a significant role in determining the selectivity of substrate and inhibitors for ChEs.
Title: Differences in active site gorge dimensions of cholinesterases revealed by binding of inhibitors to human butyrylcholinesterase Saxena A, Redman AM, Jiang X, Lockridge O, Doctor BP Ref: Biochemistry, 36:14642, 1997 : PubMed
Amino acid sequence alignments of cholinesterases revealed that 6 of 14 aromatic amino acid residues lining the active center gorge of acetylcholinesterase are replaced by aliphatic amino acid residues in butyrylcholinesterase. The Y337 (F330) in mammalian acetylcholinesterase, which is replaced by A328 in human butyrylcholinesterase, is implicated in the binding of ligands such as huperzine A, edrophonium, and acridines and one end of bisquaternary compounds such as BW284C51 and decamethonium. Y337 may sterically hinder the binding of phenothiazines such as ethopropazine, which contains a bulky exocyclic substitution. Inhibition studies of (-)-huperzine A with human butyrylcholinesterase mutants, where A328 (KI = 194.6 microM) was modified to either F (KI = 0.6 microM, as in Torpedo acetylcholinesterase) or Y (KI = 0.032 microM, as in mammalian acetylcholinesterase), confirmed previous observations made with acetylcholinesterase mutants that this residue is important for binding huperzine A. Inhibition studies of ethopropazine with butyrylcholinesterase mutants, where A328 (KI = 0.18 microM) was modified to either F (KI = 0.82 microM) or Y (KI = 0.28 microM), suggested that A328 was not solely responsible for the selectivity of ethopropazine. Volume calculations for the active site gorge showed that the poor inhibitory activity of ethopropazine toward acetylcholinesterase was due to the smaller dimension of the active site gorge which was unable to accommodate the bulky inhibitor molecule. The volume of the butyrylcholinesterase active site gorge is approximately 200 A3 larger than that of the acetylcholinesterase gorge, which allows the accommodation of ethopropazine in two different orientations as demonstrated by rigid-body refinement and molecular dynamics calculations.
Sodium pentachlorophenate (Na-PCP) has been used in China for years as an molluscacide to kill oncomelania, which is an intermediate host of Schistosome. To evaluate the effects of its long-term successive usage on environment, human exposure and health, studies were carried out in Sichuan, Jiangxi, Jiangsu and Fujian provinces, with a time gap of more than one month between sample collection and last spray of Na-PCP. Results indicated that PCP contents in surface water, soil, sediment, animals and plants were significantly higher in studied areas than in control areas. The daily intake and the content in urine of PCP were also sigificantify higher in studied areas. But, there was no difference on physical and biochemical examinations except that a 22%-28% decrease of blood cholinesterase activity was found in studied areas. The health effect of impurities in Na-PCP, dioxins and furans, was assessed and discussed.
