Title: Monoacylglycerol lipase regulates macrophage polarization and cancer progression in uveal melanoma and pan-cancer Tan Y, Pan J, Deng Z, Chen T, Xia J, Liu Z, Zou C, Qin B Ref: Front Immunol, 14:1161960, 2023 : PubMed
BACKGROUND: Although lipid metabolism has been proven to play a key role in the development of cancer, its significance in uveal melanoma (UM) has not yet been elucidated in the available literature. METHODS: To identify the expression patterns of lipid metabolism in 80 UM patients from the TCGA database, 47 genes involved in lipid metabolism were analyzed. Consensus clustering revealed two distinct molecular groups. ESTIMATE, TIMER, and ssGSEA analyses were done to identify the differences between the two subgroups in tumor microenvironment (TME) and immune state. Using Cox regression and Lasso regression analysis, a risk model based on differentially expressed genes (DEGs) was developed. To validate the expression of monoacylglycerol lipase (MGLL) and immune infiltration in diverse malignancies, a pan-cancer cohort from the UCSC database was utilized. Next, a single-cell sequencing analysis on UM patients from the GEO data was used to characterize the lipid metabolism in TME and the role of MGLL in UM. Finally, in vitro investigations were utilized to study the involvement of MGLL in UM. RESULTS: Two molecular subgroups of UM patients have considerably varied survival rates. The majority of DEGs between the two subgroups were associated with immune-related pathways. Low immune scores, high tumor purity, a low number of immune infiltrating cells, and a comparatively low immunological state were associated with a more favorable prognosis. An examination of GO and KEGG data demonstrated that the risk model based on genes involved with lipid metabolism can accurately predict survival in patients with UM. It has been demonstrated that MGLL, a crucial gene in this paradigm, promotes the proliferation, invasion, and migration of UM cells. In addition, we discovered that MGLL is strongly expressed in macrophages, specifically M2 macrophages, which may play a function in the M2 polarization of macrophages and M2 macrophage activation in cancer cells. CONCLUSION: This study demonstrates that the risk model based on lipid metabolism may be useful for predicting the prognosis of patients with UM. By promoting macrophage M2 polarization, MGLL contributes to the evolution of malignancy in UM, suggesting that it may be a therapeutic target for UM.
Title: Resistance to Beta-cypermethrin, Azadirachtin, and Matrine, and Biochemical Characterization of Field Populations of Oedaleus asiaticus (Bey-Bienko) in Inner Mongolia, Northern China Gao S, Tan Y, Han H, Guo N, Gao H, Xu L, Lin K Ref: J Insect Sci, 22:, 2022 : PubMed
Oedaleus asiaticus (Bey-Bienko) is an economically devastating locust species found in grassland and pastoral areas of the Inner Mongolia region of northern China. In this study, resistance to three frequently used insecticides (beta-cypermethrin, matrine, and azadirachtin) was investigated in six field populations of O. asiaticus using the leaf-dip bioassay method. The inhibitory effects of synergists and the activities of detoxification enzyme activities in the different populations were determined to explore potential biochemical resistance mechanisms. The results showed that the field populations SB (resistance ratio [RR]=7.85), ZB (RR=5.64), and DB (RR=6.75) had developed low levels of resistance to beta-cypermethrin compared with a susceptible control strain. Both the SB (RR=5.92) and XC (RR=6.38) populations had also developed low levels of resistance against matrine, with the other populations remaining susceptible to both beta-cypermethrin and matrine. All field populations were susceptible to azadirachtin. Synergism analysis showed that triphenyl phosphate (TPP) and diethyl-maleate (DEM) increased the toxicity of beta-cypermethrin significantly in the SB population, while the synergistic effects of TPP, piperonyl butoxide (PBO), and DEM on the toxicity of matrine were higher in SB (SR 3.86, 4.18, and 3.07, respectively) than in SS (SR 2.24, 2.86, and 2.29, respectively), but no synergistic effects of TPP, PBO, and DEM on azadirachtin were found. Biochemical assays showed that the activities of carboxylesterases (CarEs) and glutathione-S-transferases (GSTs) were significantly raised in all field populations of O. asiaticus, with a significant positive correlation observed between beta-cypermethrin resistance and CarE activity. The activities of cytochrome P450 monooxygenases (P450) and multi-function oxidases (MFO) were elevated in all six field populations, and P450 activity displayed strong positive correlations with the three insecticides. Our findings suggest that resistance to beta-cypermethrin in O. asiaticus may be mainly attributed to elevated CarE and GST activities, while P450 plays an important role in metabolizing matrine and azadirachtin. Our study provides insights that will help improve insecticide resistance management strategies.
Title: Neuronal STAT3/HIF-1alpha/PTRF axis-mediated bioenergetic disturbance exacerbates cerebral ischemia-reperfusion injury via PLA2G4A Jin W, Zhao J, Yang E, Wang Y, Wang Q, Wu Y, Tong F, Tan Y, Zhou J, Kang C Ref: Theranostics, 12:3196, 2022 : PubMed
Ischemic stroke is an acute and severe neurological disease with high mortality and disability rates worldwide. Polymerase I and transcript release factor (PTRF) plays a pivotal role in regulating cellular senescence, glucose intolerance, lipid metabolism, and mitochondrial bioenergetics, but its mechanism, characteristics, and functions in neuronal cells following the cerebral ischemia-reperfusion (I/R) injury remain to be determined. Methods: Transcription factor motif analysis, chromatin immunoprecipitation (ChIP), luciferase and co-Immunoprecipitation (co-IP) assays were performed to investigate the mechanisms of PTRF in neuronal cells after I/R injury. Lentiviral-sgRNA against PTRF gene was introduced to HT22 cells, and adeno-associated virus (AAV) encoding a human synapsin (hSyn) promoter-driven construct was transduced a short hairpin RNA (shRNA) against PTRF mRNA in primary neuronal cells and the cortex of the cerebral I/R mice for investigating the role of PTRF in neuronal damage and PLA2G4A change induced by the cerebral I/R injury. Results: Here, we reported that neuronal PTRF was remarkably increased in the cerebral penumbra after I/R injury, and HIF-1alpha and STAT3 regulated the I/R-dependent expression of PTRF via binding to its promoter in neuronal cells. Moreover, overexpression of neuronal PTRF enhanced the activity and stability of PLA2G4A by decreasing its proteasome-mediated degradation pathway. Subsequently, PTRF promoted reprogramming of lipid metabolism and altered mitochondrial bioenergetics, which could lead to oxidative damage, involving autophagy, lipid peroxidation, and ferroptosis via PLA2G4A in neuronal cells. Furthermore, inhibition of neuronal PTRF/PLA2G4A-axis markedly reduced the neurological deficits, cerebral infarct volumes, and mortality rates in the mice following cerebral I/R injury. Conclusion: Our results thus identify that the STAT3/HIF-1alpha/PTRF-axis in neurons, aggravating cerebral I/R injury by regulating the activity and stability of PLA2G4A, might be a novel therapeutic target for ischemic stroke.
Title: Characterization of the anti-AChE potential and alkaloids in Rhizoma Coptidis from different Coptis species combined with spectrum-effect relationship and molecular docking Qi L, Zhong F, Liu N, Wang J, Nie K, Tan Y, Ma Y, Xia L Ref: Front Plant Sci, 13:1020309, 2022 : PubMed
Coptis species are the main source of Rhizoma Coptidis (RC) drugs, which have always been used to treat Alzheimer's disease in the clinical experience of ancient China. However, many species of this genus have been largely underutilized until now. With this fact, this research has been designed to investigate for the first time the anti-acetylcholinesterase (AChE) property of different extracts for RC drugs from four Coptis species (C. chinensis, C. deltoidea, C. teeta and C. omeiensis) and to quantify the main alkaloids. Petroleum ether, ethyl acetate and n-butanol fractions of RC drugs were sequentially collected using an accelerated solvent extraction technique. Spectrum-effect relationship and molecular docking were applied to analyse the relationships between alkaloids and AChE inhibitory activity. The N-butanol extract was proven to be the main active fraction, and C. teeta may be the best source of RC drugs for Alzheimer's disease treatment, with significantly lower IC 20, IC 50 and IC 80 values for AChE inhibition. The UPLC/QqQ-MS quantitative analysis showed that the accumulations of 10 alkaloids in RC drugs from different sources greatly varied. Three data processing methods (Random forest, Boruta and Pearson correlation) comprehensively analysed the spectrum-effect relationship and revealed that columbamine, berberine and palmatine were the most important AChE inhibitors that could be used as quality markers to select RC drugs for Alzheimer's disease treatment. In addition, the dominant compounds were successfully docked against AChE to verify the binding affinity and interactions with the active site. The present study can contribute to the reasonable development and utilization of RC drugs from different sources, especially to provide certain evidence for their application in the treatment of Alzheimer's disease.
Title: Extracellular secretion of a cutinase with polyester-degrading potential by E. coli using a novel signal peptide from Amycolatopsis mediterranei Tan Y, Henehan GT, Kinsella GK, Ryan BJ Ref: World J Microbiol Biotechnol, 38:60, 2022 : PubMed
Recent studies in this laboratory showed that an extracellular cutinase from A. mediterranei (AmCut) was able to degrade the plastics polycaprolactone and polybutylene succinate. Such plastics can be slow to degrade in soils due to a lack of efficient polyester degrading organisms. AmCut also showed potential for the biocatalytic synthesis of esters by reverse hydrolysis. The gene for AmCut has an upstream leader sequence whose transcript is not present in the purified enzyme. In this study, we show using predictive modelling, that this sequence codes for an N-terminal signal peptide that directs transmembrane expression via the Sec secretion pathway. E. coli is a useful host for recombinant enzymes used in biocatalysis due to the ease of genetic manipulation in this organism, which allows tuning of enzymes for specific applications, by mutagenesis. When a truncated GST-tagged AmCut gene (lacking its signal peptide) was expressed in E. coli, all cutinase activity was observed in the cytosolic fraction. However, when GST-tagged AmCut was expressed in E. coli along with its native signal peptide, cutinase activity was observed in both the periplasmic space and the culture medium. This finding revealed that the native signal peptide of a Gram-positive organism (AmCut) was being recognised by the Gram-negative (E. coli) Sec transmembrane transport system. AmCut was transported into E. coli's periplasmic space from where it was released into the culture medium. Surprisingly, the presence of a bulky GST tag at the N-terminus of the signal peptide did not hinder transmembrane targeting. Although the periplasmic targeting was unexpected, it is not unprecedented due to the conservation of the Sec pathway across species. It was more surprising that AmCut was secreted from the periplasmic space into the culture medium. This suggests that extracellular AmCut translocation across the E. coli outer membrane may involve non-classical secretion pathways. This tuneable recombinant E. coli expressing extracellular AmCut may be useful for degradation of polyester substrates in the environment; this and other applications are discussed.
Title: Enantioselective Metabolic Mechanism and Metabolism Pathway of Pydiflumetofen in Rat Liver Microsomes: In Vitro and In Silico Study Wang Z, Li R, Wu Q, Duan J, Tan Y, Sun X, Chen R, Shi H, Wang M Ref: Journal of Agricultural and Food Chemistry, 70:2520, 2022 : PubMed
Pydiflumetofen (PYD) has been used worldwide. However, the enantioselective fate of PYD within mammals is not clear. Thus, the enantioselective metabolism and its potential mechanisms of PYD were explored via in vitro and in silico. Consistent results were observed between metabolism and enzyme kinetics experiments, with S-PYD metabolizing faster than R-PYD in rat liver microsomes. Moreover, CYP3A1 and carboxylesterase 1 were found to be major enzymes participating in the metabolism of PYD. Based on the computational results, S-PYD bound with CYP3A1 and carboxylesterase 1 more tightly with lower binding free energy than R-PYD, explaining the mechanism of enantioselective metabolism. Nine phase I metabolites of PYD were identified, and metabolic pathways of PYD were speculated. This study is the first to clarify the metabolism of PYD in mammals, and further research to evaluate the toxicological implications of these metabolites will help in assessing the risk of PYD.
Cytoplasmic lipid droplets (LDs) can store neutral lipids as an energy source when needed and also regulate the key metabolic processes of intracellular lipid accumulation, which is associated with several metabolic diseases. The perilipins (Plins) are a family of proteins that associate with the surface of LDs. As a member of Plins superfamily, perilipin 5 (Plin5) coats LDs in cardiomyocytes, which is significantly related to reactive oxygen species (ROS) production originated from mitochondria in the heart, consequently determining the progression of diabetic cardiomyopathy. Plin5 may play a bidirectional function in lipid metabolism which is in a state of dynamic balance. In the basic state, Plin5 inhibited the binding of comparative gene identification-58 (CGI-58) to adipose triglyceride lipase (ATGL) by binding CGI-58, thus inhibiting lipolysis. However, when the body is under stress (such as cold, fasting, exercise, and other stimuli), protein kinase A (PKA) phosphorylates and activates Plin5, which then causes Plin5 to release the binding site of CGI-58 and ATGL, prompting CGI-58 to bind to ATGL and activate ATGL activity, thus accelerating the lipolysis process, revealing the indispensable role of Plin5 in lipid turnover. Here, the purpose of this review is to summarize the present understanding of the bidirectional regulation role of Plin5 in oxidative tissues and to reveal its potential role in diabetic cardiomyopathy protection.
Title: Bioactive Polyketide and Diketopiperazine Derivatives from the Mangrove-Sediment-Derived Fungus Aspergillus sp. SCSIO41407 Cai J, Chen C, Tan Y, Chen W, Luo X, Luo L, Yang B, Liu Y, Zhou X Ref: Molecules, 26:, 2021 : PubMed
Ten polyketide derivatives (1-10), including a new natural product named (E)-2,4-dihydroxy-3-methyl-6-(2-oxopent-3-en-1-yl) benzaldehyde (1), and five known diketopiperazines (11-15), were isolated from the mangrove-sediment-derived fungus Aspergillus sp. SCSIO41407. The structures of 1-15 were determined via NMR and MS spectroscopic analysis. In a variety of bioactivity screening, 3 showed weak cytotoxicity against the A549 cell line, and 2 exhibited weak antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA). Compounds 3, 5, and 6 showed inhibition against acetylcholinesterase (AChE) with IC(50) values of 23.9, 39.9, and 18.6 microM. Compounds 11, 12, and 14 exhibited obvious inhibitory activities of lipopolysaccharide (LPS)-induced nuclear factor-kappaB (NF-kappaB) with IC(50) values of 19.2, 20.9, and 8.7 microM, and they also suppressed RANKL-induced osteoclast differentiation in bone marrow macrophages cells (BMMCs), with the concentration of 5 microM. In silico molecular docking with AChE and NF-kappaB p65 protein were also performed to understand the inhibitory activities, and 1, 11-14 showed obvious protein/ligand-binding effects to the NF-kappaB p65 protein.
Title: Juvenile hormone regulates the reproductive diapause through Methoprene-tolerant gene in Galeruca daurica Ma HY, Li YY, Li L, Tan Y, Pang BP Ref: Insect Molecular Biology, :, 2021 : PubMed
Juvenile hormone (JH) signaling plays an important role in regulation of reproductive diapause in insects. However, its underlying molecular mechanism has been unclear. Methoprene-tolerant (Met), as a universal JH receptor, is involved in JH action. To gain some insight into its function in the reproductive diapause of Galeruca daurica, a serious pest on the Inner Mongolia grasslands undergoing obligatory summer diapause at the adult stage, we cloned the complete open-reading frame (ORF) sequences of Met and other 7 JH signaling-related genes, including JH acid methyltransferase (JHAMT), JH esterase (JHE), JH epoxide hydrolase (JHEH), Kruppel homolog 1 (Kr-h1), vitellogenin (Vg), forkhead box O (FOXO), and fatty acid synthase 2 (FAS2), from this species. GdMet encoded a putative protein, which contained three domains typical of the bHLH-PAS family. Expression patterns of these 8 genes were developmentally regulated during adult development. Topical application of JH analog (JHA) methoprene into the 3-day-old and 5-day-old adults induced the expression of GdMet. Silencing GdMet by RNAi inhibited the expression of JHBP, JHE, Kr-h1, and Vg, whereas promoted the FAS2 expression, which enhanced lipid accumulation and fat body development, and finally induced the adults into diapause ahead. Combining with our previous results, we conclude that JH may regulate reproductive diapause through a conserved Met-dependent pathway in G. daurica.
Title: An extracellular lipase from Amycolatopsis mediterannei is a cutinase with plastic degrading activity Tan Y, Henehan GT, Kinsella GK, Ryan BJ Ref: Comput Struct Biotechnol J, 19:869, 2021 : PubMed
An extracellular lipase from Amycolatopsis mediteranei (AML) with potential applications in process biotechnology was recently cloned and examined in this laboratory. In the present study, the 3D structure of AML was elucidated by comparative modelling. AML lacked the 'lid' structure observed in most true lipases and shared similarities with plastic degrading enzymes. Modelling and substrate specificity studies showed that AML was a cutinase with a relatively exposed active site and specificity for medium chain fatty acyl moieties. AML rapidly hydrolysed the aliphatic plastics poly(sigma-caprolactone) and poly(1,4-butylene succinate) extended with 1,6-diisocyanatohexane under mild conditions. These plastics are known to be slow to degrade in landfill. Poly(L-lactic acid) was not hydrolysed by AML, nor was the aromatic plastic Polyethylene Terephthalate (PET). The specificity of AML is partly explained by active site topology and analysis reveals that minor changes in the active site region can have large effects on substrate preference. These findings show that extracellular Amycolatopsis enzymes are capable of degrading a wider range of plastics than is generally recognised. The potential for application of AML in the bioremediation of plastics is discussed.
BACKGROUND: The brain-gut-microbiota axis plays a crucial role in the bidirectional interactions between the brain and the gut. Soluble epoxide hydrolase (coded by the Ephx2 gene) plays an important role in inflammation, which has been implicated in stress-related depression. Ephx2 knock-out (KO) mice exposed to chronic social defeat stress (CSDS) did not show depression-like behaviors, indicating stress resilience. Here we examined whether the brain-gut-microbiota axis influences the resilience in Ephx2 KO mice. METHODS: Effects of fecal microbiota transplantation (FMT) from CSDS-susceptible (or control) mice in wild-type (WT) mice and Ephx2 KO mice treated with an antibiotic cocktail (ABX) were investigated. Behavioral, biochemical tests and 16S ribosome RNA analysis were performed. RESULTS: FMT from CSDS-susceptible mice produced anhedonia-like behavior in ABX-treated WT and Ephx2 KO mice. The 16S ribosome RNA analysis showed that Faecalibaculum rodentium (F. rodentium) may be responsible for the observed anhedonia-like behavior following FMT from CSDS-susceptible mice. Ingestion of F. rodentium for 14 days produced depression- and anhedonia-like behaviors, higher blood levels of interleukin-6, and reduced expression of synaptic proteins in the prefrontal cortex of ABX-treated Ephx2 KO mice. Furthermore, subdiaphragmatic vagotomy blocked the development of these behavioral abnormalities after ingestion of F. rodentium. LIMITATIONS: Detailed mechanisms are unclear. CONCLUSIONS: These findings suggest that F. rodentium might contribute to the conversion of resilient Ephx2 KO mice into KO mice with depression-like phenotypes. The brain-gut-microbiota axis via the subdiaphragmatic vagus nerve plays a crucial role in susceptibility and resilience to stress.
Title: Identification and characterization of a novel carboxylesterase EstQ7 from a soil metagenomic library Yan Z, Ding L, Zou D, Wang L, Tan Y, Guo S, Zhang Y, Xin Z Ref: Arch Microbiol, :, 2021 : PubMed
A novel lipolytic gene, estq7, was identified from a fosmid metagenomic library. The recombinant enzyme EstQ7 consists of 370 amino acids with an anticipated molecular mass of 42 kDa. Multiple sequence alignments showed that EstQ7 contained a pentapeptide motif GHSMG, and a putative catalytic triad Ser174-Asp306-His344. Interestingly, EstQ7 was found to have very little similarity to the characterized lipolytic enzymes. Phylogenetic analysis revealed that EstQ7 may be a member of a novel family of lipolytic enzymes. Biochemical characterization of the recombinant enzyme revealed that it constitutes a slightly alkalophilic, moderate thermophilic and highly active carboxylesterase against short-chain fatty acid esters with optimum temperature 50 degC and pH 8.2. The Km and kcat values toward p-nitrophenyl acetate were determined to be 0.17 mM and 1910s(-1), respectively. Moreover, EstQ7 was demonstrated to have acyltransferase activity by GC-MS analysis. Structural modeling of the three-dimensional structure of this new enzyme showed that it exhibits a typical alpha/beta hydrolase fold, and the catalytic triad residues are spatially close. Molecular docking revealed the interactions between the enzyme and the ligand. The high levels of lipolytic activity of EstQ7, combined with its moderate thermophilic property and acyltransferase activity, render this novel enzyme a promising candidate biocatalyst for food, pharmaceutical and biotechnological applications.
Title: The rs1051931 G>A Polymorphism in the PLA2G7 Gene Confers Resistance to Immunoglobulin Therapy in Kawasaki Disease in a Southern Chinese Population Gu X, Lin W, Xu Y, Che D, Tan Y, Lu Z, Pi L, Fu L, Zhou H, Jiang Z Ref: Front Pediatr, 8:338, 2020 : PubMed
Background: Kawasaki disease (KD) is a common cardiovascular disease in infants and young children, with fever, rash, and conjunctivitis as the main clinical manifestations, which can lead to the occurrence of coronary aneurysms. Intravenous immunoglobulin (IVIG) is the preferred treatment for KD patients, but 10-20% of patients are resistant to IVIG. Lipoprotein-associated phospholipase A 2 (Lp-PLA2) is a potential therapeutic target for coronary atherosclerotic heart disease, and the polymorphism of Phospholipase A2 Group VII (PLA2G7) is closely related to the activity of Lp-PLA2, of which rs1051931 is the strongest. Therefore, the rs1051931 polymorphism may be a predictor of IVIG resistance in KD patients. Methods: A total of 760 KD cases, including 148 IVIG-resistant patients and 612 IVIG-responsive patients, were genotyped for rs1051931 in PLA2G7, we compared the effects of rs1051931 on IVIG treatment in KD patients by odds ratios (OR) and 95% confidence interval (CI). Results: The homozygous mutation AA may be a protective factor for IVIG resistance in KD patients (adjusted OR = 3.47, 95% CI = 1.14-10.57, P = 0.0284) and is more evident in patients with KD aged <60 months (adjusted OR = 3.68, 95% CI = 1.10-12.28, P = 0.0399). Conclusions: The PLA2G7 rs1051931 G>A polymorphism may be suitable as a biomarker for the diagnosis or prognosis of IVIG resistance in KD in a southern Chinese population.
Epidemiological studies suggest that exposure to herbicides during pregnancy might increase risk for autism spectrum disorder (ASD) in offspring. However, the precise mechanisms underlying the risk of ASD by herbicides such as glyphosate remain unclear. Soluble epoxide hydrolase (sEH) in the metabolism of polyunsaturated fatty acids is shown to play a key role in the development of ASD in offspring after maternal immune activation. Here, we found ASD-like behavioral abnormalities in juvenile offspring after maternal exposure to high levels of formulated glyphosate. Furthermore, we found higher levels of sEH in the prefrontal cortex (PFC), hippocampus, and striatum of juvenile offspring, and oxylipin analysis showed decreased levels of epoxy-fatty acids such as 8 (9)-EpETrE in the blood, PFC, hippocampus, and striatum of juvenile offspring after maternal glyphosate exposure, supporting increased activity of sEH in the offspring. Moreover, we found abnormal composition of gut microbiota and short-chain fatty acids in fecal samples of juvenile offspring after maternal glyphosate exposure. Interestingly, oral administration of TPPU (an sEH inhibitor) to pregnant mothers from E5 to P21 prevented ASD-like behaviors such as social interaction deficits and increased grooming time in the juvenile offspring after maternal glyphosate exposure. These findings suggest that maternal exposure to high levels of glyphosate causes ASD-like behavioral abnormalities and abnormal composition of gut microbiota in juvenile offspring, and that increased activity of sEH might play a role in ASD-like behaviors in offspring after maternal glyphosate exposure. Therefore, sEH may represent a target for ASD in offspring after maternal stress from occupational exposure to contaminants.
Title: Increased expression of soluble epoxide hydrolase in the brain and liver from patients with major psychiatric disorders: A role of brain - liver axis Zhang J, Tan Y, Chang L, Hammock BD, Hashimoto K Ref: J Affect Disord, 270:131, 2020 : PubMed
BACKGROUND: Soluble epoxide hydrolase (sEH) in the metabolism of polyunsaturated fatty acids might play a role in the pathogenesis of major psychiatric disorders. Here we studied whether expression of sEH protein is altered in the postmortem samples (parietal cortex, and liver) from patients with major psychiatric disorders. METHODS: Protein expression of sEH in the parietal cortex and liver from control, major depressive disorder (MDD), bipolar disorder (BD), and schizophrenia (SZ) groups was measured. RESULTS: Levels of sEH in the parietal cortex and liver from MDD, BD, and SZ groups were significantly higher than the control group. Interestingly, there was a positive correlation between sEH protein in the parietal cortex and sEH protein the liver in all groups. LIMITATIONS: The small number in each group may limit our interpretation. CONCLUSIONS: This study shows that the increased expression of sEH in the brain and liver might play a role in the pathogenesis of major psychiatric disorders, suggesting a role of brain - liver axis in major psychiatric disorders.
Title: Molecular and functional properties of two Spodoptera exigua acetylcholinesterase genes Zhao J, Hao D, Xiao L, Tan Y, Jiang Y, Bai L, Wang K Ref: Archives of Insect Biochemistry & Physiology, :e21554, 2019 : PubMed
Acetylcholinesterase (AChE) is a vital enzyme that hydrolyzes acetylcholine. Here, full-length complementary DNAs (cDNAs) of two acetylcholinesterase genes (SeAce1 and SeAce2) were obtained from Spodoptera exigua, a widespread phytophagous pest in agriculture. The complete SeAce1 cDNA comprised 5447 nucleotides including an open reading frame (ORF) encoding 694 amino acids, while SeAce2 cDNA encompassed a 1917-bp ORF which would likely yield 638 amino acids. Both SeAce1 and SeAce2 contained specific characteristics of functional AChE. A phylogenetic tree of all lepidopteran insect Aces showed S. exigua clustered with S. litura, Helicoverpa assulta, and H. armigera, all of which are Noctuidae. In S. exigua, SeAce1 gene expression levels (reverse transcription polymerase chain reaction [RT-PCR] and quantitative RT-PCR) were markedly increased compared with SeAce2 in all developmental phases and tissue types. Both genes were down regulated by inserting the corresponding dsRNAs in 5th instar larvae, which resulted in 56.7% (SeAce1) and 24.6% (SeAce2) death. Downregulation of both SeAce1 and SeAce2 significantly reduced fecundity and vitellogenin gene expression in S. exigua. These results revealed the biological functions of the two Ace genes (SeAce1 and SeAce2), providing novel insights into the development of strategies for controlling insect pests.
Title: Inhibition of Butyrylcholinesterase with Fluorobenzylcymserine, An Experimental Alzheimer's Drug Candidate: Validation of Enzoinformatics Results by Classical and Innovative Enzyme Kinetic Analyses Kamal MA, Shakil S, Nawaz MS, Yu QS, Tweedie D, Tan Y, Qu X, Greig NH Ref: CNS Neurol Disord Drug Targets, 16:820, 2017 : PubMed
BACKGROUND: Selective butyrylcholinesterase (BuChE)-inhibition, increases acetylcholine (ACh) levels. In rodents, this inhibition is known to boost cognition. Also, this occurs without the typical unwanted adverse effects of acetylcholinesterase-inhibitors or AChE-Is. The novel compound, fluorobenzylcymserine (FBC), is derived from our effort to design a selective BuChE-inhibitor. Also, we wanted to check whether butyrylcholinesterase-inhibitors (BuChE-Is) possessed an edge over AChE-Is in Alzheimer's disease (AD) in terms of efficacy and/or tolerance. METHOD: FBC was synthesized as reported earlier while enzymatic activity of BuChE was calculated by Ellman-technique. Molecular docking was performed using Autodock4.2. We applied classical as well as innovative analyses of enzyme-kinetics for exploring "FBC:human BuChE-interaction". The mode of inhibition and kinetic parameters were also determined. RESULTS: Docking results displayed two strong interacting sites for FBC. One of these binding sites was previously identified as a deep narrow groove having polar aromatic residues while a second site was identified during this study which displayed better interaction and was lined with aliphatic and sulphur containing residues. At low concentrations of BuChE, the IC50 was found to be very low i.e. 4.79 and 6.10 nM for 12 and 36 microg, respectively, whereas it increased exponentially by increasing the units of BuChE. CONCLUSION: These analyses indicate that FBC is an interesting AD drug candidate that could provide a potent and partial mixed type of inhibition of human BuChE.
Title: Comparative genomic and transcriptomic analyses of the Fuzhuan brick tea-fermentation fungus Aspergillus cristatus Ge Y, Wang Y, Liu Y, Tan Y, Ren X, Zhang X, Hyde KD, Liu Z Ref: BMC Genomics, 17:428, 2016 : PubMed
BACKGROUND: Aspergillus cristatus is the dominant fungus involved in the fermentation of Chinese Fuzhuan brick tea. Aspergillus cristatus is a homothallic fungus that undergoes a sexual stage without asexual conidiation when cultured in hypotonic medium. The asexual stage is induced by a high salt concentration, which completely inhibits sexual development. The taxon is therefore appropriate for investigating the mechanisms of asexual and sexual reproduction in fungi. In this study, de novo genome sequencing and analysis of transcriptomes during culture under high- and low-osmolarity conditions were performed. These analyses facilitated investigation of the evolution of mating-type genes, which determine the mode of sexual reproduction, in A. cristatus, the response of the high-osmolarity glycerol (HOG) pathway to osmotic stimulation, and the detection of mycotoxins and evaluation of the relationship with the location of the encoding genes. RESULTS: The A. cristatus genome comprised 27.9 Mb and included 68 scaffolds, from which 10,136 protein-coding gene models were predicted. A phylogenetic analysis suggested a considerable phylogenetic distance between A. cristatus and A. nidulans. Comparison of the mating-type gene loci among Aspergillus species indicated that the mode in A. cristatus differs from those in other Aspergillus species. The components of the HOG pathway were conserved in the genome of A. cristatus. Differential gene expression analysis in A. cristatus using RNA-Seq demonstrated that the expression of most genes in the HOG pathway was unaffected by osmotic pressure. No gene clusters associated with the production of carcinogens were detected. CONCLUSIONS: A model of the mating-type locus in A. cristatus is reported for the first time. Aspergillus cristatus has evolved various mechanisms to cope with high osmotic stress. As a fungus associated with Fuzhuan tea, it is considered to be safe under low- and high-osmolarity conditions.
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: Contribution of carboxylesterase and cytochrome p450 to the bioactivation and detoxification of isocarbophos and its enantiomers in human liver microsomes Zhuang XM, Wei X, Tan Y, Xiao WB, Yang HY, Xie JW, Lu C, Li H Ref: Toxicol Sci, 140:40, 2014 : PubMed
Organophosphorus pesticides are the most widely used pesticides in modern agricultural systems to ensure good harvests. Isocarbophos (ICP), with a potent acetylcholinesterase inhibitory effect is widely utilized to control a variety of leaf-eating and soil insects. However, the characteristics of the bioactivation and detoxification of ICP in humans remain unclear. In this study, the oxidative metabolism, esterase hydrolysis, and chiral inversion of ICP in human liver microsomes (HLMs) were investigated with the aid of a stereoselective LC/MS/MS method. The depletion of ICP in HLMs was faster in the absence of carboxylesterase inhibitor (BNPP) than in the presence of NADPH and BNPP, with t1/2 of 5.2 and 90 min, respectively. Carboxylesterase was found to be responsible for the hydrolysis of ICP, the major metabolic pathway. CYP3A4, CYP1A2, CYP2D6, CYP2C9, and CYP2C19 were all involved in the secondary metabolism pathway of desulfuration of ICP. Flavin-containing monooxygenase (FMO) did not contribute to the clearance of ICP. The hydrolysis and desulfuration of (+/-)ICP, (+)ICP, and (-)ICP in HLMs follow Michaelis-Menten kinetics. Individual enantiomers of ICP and its oxidative desulfuration metabolite isocarbophos oxon (ICPO) were found to be inhibitors of acetylcholinesterases at different extents. For example, (+/-)ICPO is more potent than ICP (IC50 0.031muM vs. 192muM), whereas (+)ICPO is more potent than (-)ICPO (IC50 0.017muM vs. 1.55muM). Given the finding of rapid hydrolysis of ICP and low abundance of oxidative metabolites presence in human liver, the current study highlights that human liver has a greater capacity for detoxification of ICP.
A novel series of tacrine-caffeic acid hybrids (5a-f) were designed and synthesized by combining caffeic acid (CA) with tacrine. The antioxidant study revealed that all the hybrids have much more antioxidant capacities compared to CA. Among these compounds, 5e showed the highest selectivity in inhibiting acetylcholinesterase (AChE) over butyrylcholinesterase (BuChE). Enzyme kinetic study had suggested that 5e binds to both catalytic (CAS) and peripheral anionic sites (PAS) of AChE. Moreover, compound 5e also inhibited self- or AChE-induced beta-amyloid(1-40) aggregation, as well as had potent neuroprotective effects against H(2)O(2)- and glutamate- induced cell death with low toxicity in HT22 cells.
Pseudomonas sp. USM 4-55 is a locally isolated bacterium that possesses the ability to produce polyhydroxyalkanoates (PHA) consisting of both poly(3-hydroxybutyrate) [P(3HB)] homopolymer and medium-chain length (mcl) monomers (6 to 14 carbon atoms) when sugars or fatty acids are utilized as the sole carbon source. In this study, the P(3HB) biosynthesis operon carrying the phbC(Ps) P(3HB) synthase was successfully cloned and sequenced using a homologous probe. Three open reading frames encoding NADPH-dependent acetoacetyl-coenzyme A reductase (PhbB(Ps)), beta-ketothiolase (PhbA(Ps)) and P(3HB) synthase (PhbC(Ps)) were found in the phb operon. The genetic organization of phb operon showed a putative promoter region, followed by phbB(Ps)-phbA(Ps)-phbC(Ps). phbR(Ps)which encoded a putative transcriptional activator was located in the opposite orientation, upstream of phbBAC(Ps). Heterologous expression of pGEM''ABex harboring phbC(Ps) in Escherichia coli JM109 resulted in P(3HB) accumulation of up to 40% of dry cell weight (DCW).
Title: Targeting BuChE-inflammatory pathway by SK0506 to manage type 2 diabetes and Alzheimer disease Kamal MA, Tan Y, Seale JP, Qu X Ref: Neurochem Res, 34:2163, 2009 : PubMed
Type 2 diabetes mellitus (T2DM) and Alzheimer's disease (AD) affect a large percent of the population worldwide. Experimental studies have revealed that T2DM and AD share several molecular processes that underlie their respective degenerative pathology. Based on this information, we quantified TNF-alpha, IL-6 levels, serum glucose, serum triglyceride, hepatic triglyceride, serum AST, serum ALT and butyrylcholinesterase (BuChE) in various rat tissues. HFD was fed to rats resulting in increased body weight, fasting blood glucose, IL-6, TNF-alpha levels, hepatic triglyceride, serum AST, serum ALT and BuChE. SK0506 treatment significantly prevented weight gain induced by HFD feeding. SK0506, but not Rosiglitazone, significantly reduced serum and hepatic triglycerides levels. Treatment with SK0506 also ameliorated elevated levels of both inflammatory markers (TNF-alpha and IL-6) and serum liver enzymes (ALT and AST) significantly in HFD fed rats. BuChE activity also reduced in skeletal muscle and adipose tissues of rats treated by SK0506. In conclusion, current study has opened new potential avenues towards research for management of T2DM and AD by Chinese herbal extracts, ''SK0506''.
Infantile neuronal ceroid lipofuscinosis (INCL, Infantile Batten Disease) is an inherited, neurodegenerative lysosomal storage disorder. INCL is the result of a CLN1 gene mutation leading to a deficiency in palmitoyl protein thioesterase 1 (PPT1) activity. Studies in the forebrain demonstrate the PPT1-deficient mouse (PPT1-/-) mimics the clinical symptoms and underlying pathology of INCL; however, little is known about changes in cerebellar function or pathology. In this study, we demonstrate Purkinje cell loss beginning at 3 months, which correlates with changes in rotarod performance. Concurrently, we observed an early stage reactive gliosis and a primary pathology in astrocytes, including changes in S100beta and GLAST expression. Conversely, there was a late stage granule cell loss, microglial activation, and demyelination. This study suggests that neuronal-glial interactions are the core pathology in the PPT1-/- cerebellum. In addition, these data identify potential endpoints for use in future efficacy studies for the treatment of INCL.
Title: Tetrahydrofurobenzofuran cymserine, a potent butyrylcholinesterase inhibitor and experimental Alzheimer drug candidate, enzyme kinetic analysis Kamal MA, Qu X, Yu QS, Tweedie D, Holloway HW, Li Y, Tan Y, Greig NH Ref: J Neural Transm (Vienna), 115:889, 2008 : PubMed
Synaptic loss, particularly related to the forebrain cholinergic system, is considered to be an early event that leads to Alzheimer's disease (AD) and has led to the development of acetylcholinesterase inhibitors (AChE-Is) as the mainstay of treatment for several degenerative disorders that culminate in dementia. The primary dose-limiting toxicities of all clinically available AChE-Is are, similar to useful actions on cognition, cholinergically mediated and they ultimately limit the value of this drug class in achieving anything but symptomatic improvements. In addition, AChE levels in brain areas associated with AD decline with disease progression, which likely ultimately limits the therapeutic utility of this drug class. New research indicates that selective inhibition of butyrylcholinesterase (BuChE), a closely related enzyme that is markedly elevated in AD brain, increases acetylcholine (ACh) and augments cognition in rodents free of the characteristic undesirable actions of AChE-Is. BuChE inhibition hence represents an innovative treatment approach for AD, and agents are currently being synthesized to optimally achieve this. The novel compound, tetrahydrofurobenzofuran cymserine (THFBFC), is derived from our effort to produce a potent and BuChE-selective inhibitor as a candidate to test the hypothesis that BuChE-Is would be efficacious and better tolerated than AChE-Is in AD. Herein, we applied innovative enzyme kinetic analyses to characterize the quantitative interaction of THFBFC with human BuChE. These provided values for the agent's IC(50), together with specific new kinetic constants, such as K (T50), K (T1/2), R (I), (o)K (RT), (o)P(max), K(PT) and PT(1/2), to aid define target concentrations for clinical translation. Additional classical kinetic parameters, including K(i), K(m)or K(s), k(cat) or V(max) and V (mi) were also determined. THFBFC proved to be a potent competitive inhibitor of human BuChE and, like its isomer dihydrobenzodioxepine cymserine, is a potentially interesting AD drug candidate.
Title: Different amino-acid substitutions confer insecticide resistance through acetylcholinesterase 1 insensitivity in Culex vishnui and Culex tritaeniorhynchus (Diptera: Culicidae) from China Alout H, Berthomieu A, Cui F, Tan Y, Berticat C, Qiao C, Weill M Ref: Journal of Medical Entomology, 44:463, 2007 : PubMed
Insecticide resistance owing to insensitive acetylcholinesterase (AChE)1 has been reported in several mosquito species, and only two mutations in the ace-1 gene have been implicated in resistance: 119S and 331W substitutions. We analyzed the AChE1 resistance status of Culex vishnui (Theobald) and Culex tritaeniorhynchus Giles sampled in various regions of China. These two species displayed distinct mutations leading to AChE1 insensitivity; the 119S substitution in resistant C. vishnui mosquitoes and the 331W substitution in resistant C. tritaeniorhynchus. A biochemical test was validated to detect the 331W mutation in field samples. The comparison of the recombinant G119S and 331W mutant proteins produced in vitro with the AChE1 extracted from resistant mosquitoes indicated that the AChE1 insensitivity observed could be specifically attributed to these substitutions. Comparison of their biochemical characteristics indicated that the resistance conferred by these mutations depends on the insecticide used, regardless of its class. This resistance seemed to be fixed in the Cx. tritaeniorhynchus populations sampled in a 2000-km transect, suggesting a very high level of insecticide application or a low fitness cost associated with this 331W mutation.
Title: Filariasis vector in China: insecticide resistance and population structure of mosquito Culex pipiens complex Cui F, Tan Y, Qiao C-L Ref: Pest Manag Sci, 63:453, 2007 : PubMed
Seven field populations of mosquito Culex pipiens complex (Diptera: Culicidae) were collected from four provinces of China. The resistance status of larvae to dichlorvos, parathion, chlorpyrifos, fenobucarb (BPMC) and propoxur were determined by bioassays, disclosing that they were more resistant to organophosphate (moderate or low resistance) than to carbamate (low or no significant resistance) insecticides. Starch gel electrophoresis confirmed the presence and distribution of overproduced esterases B1, A2-B2, A8-B8 and A9-B9, the frequencies of which varied according to their regional origins. Electrophoretic polymorphism at four putatively neutral loci (got-1, got-2, pgi and pgm) showed that the overall genetic differentiation found across all populations was significantly large (Fst = 0.28, P < 10(-4)), and genetic exchange was slightly restricted by distance isolation (P = 0.018).
Ascoviruses (family Ascoviridae) are double-stranded DNA viruses with circular genomes that attack lepidopterans, where they produce large, enveloped virions, 150 by 400 nm, and cause a chronic, fatal disease with a cytopathology resembling that of apoptosis. After infection, host cell DNA is degraded, the nucleus fragments, and the cell then cleaves into large virion-containing vesicles. These vesicles and virions circulate in the hemolymph, where they are acquired by parasitic wasps during oviposition and subsequently transmitted to new hosts. To develop a better understanding of ascovirus biology, we sequenced the genome of the type species Spodoptera frugiperda ascovirus 1a (SfAV-1a). The genome consisted of 156,922 bp, with a G+C ratio of 49.2%, and contained 123 putative open reading frames coding for a variety of enzymes and virion structural proteins, of which tentative functions were assigned to 44. Among the most interesting enzymes, due to their potential role in apoptosis and viral vesicle formation, were a caspase, a cathepsin B, several kinases, E3 ubiquitin ligases, and especially several enzymes involved in lipid metabolism, including a fatty acid elongase, a sphingomyelinase, a phosphate acyltransferase, and a patatin-like phospholipase. Comparison of SfAV-1a proteins with those of other viruses showed that 10% were orthologs of Chilo iridescent virus proteins, the highest correspondence with any virus, providing further evidence that ascoviruses evolved from a lepidopteran iridovirus. The SfAV-1a genome sequence will facilitate the determination of how ascoviruses manipulate apoptosis to generate the novel virion-containing vesicles characteristic of these viruses and enable study of their origin and evolution.
Title: Cloning, expression, and nucleotide sequence of a lipase gene from Pseudomonas fluorescens B52 Tan Y, Miller KJ Ref: Applied Environmental Microbiology, 58:1402, 1992 : PubMed
In this study, we report the cloning and expression of lipase gene from Pseudomonas fluorescens B52, a psychrotrophic spoilage bacterium isolated from refrigerated raw milk. Sequence analysis revealed one major open reading frame of 1,428 nucleotides that was predicted to encode a protein with a molecular weight of 50,241. The predicted enzyme was found to contain an amino acid sequence highly homologous to the putative substrate-binding domain present within all lipases examined to date.
