BACKGROUND AND AIMS: Hepatosteatosis is one of the early features of alcoholic liver disease (ALD) and pharmaceutical or genetic interfering of the development of hepatosteatosis will efficiently alleviate the progression of ALD. Currently, the role of histone methyltransferase Setdb1 in ALD is not yet well understood. METHOD: Lieber-De Carli diet mice model and NIAAA mice model were constructed to confirm the expression of Setdb1. The hepatocyte-specific Setdb1-knockout (Setdb1-HKO) mice was established to determine the effects of Setdb1 in vivo. Adenovirus-Setdb1 were produced to rescue the hepatic steatosis in both Setdb1-HKO and Lieber-De Carli mice. The enrichment of H3k9me3 in the upstream sequence of Plin2 and the chaperone-mediated autophagy (CMA) of Plin2 were identified by ChIP and co-IP. Dual-luciferase reporter assay was used to detect the interaction of Setdb1 3'UTR and miR216b-5p in AML12 or HEK 293 T cells. RESULTS: We found that Setdb1 was downregulated in the liver of alcohol-fed mice. Setdb1 knockdown promoted lipid accumulation in AML12 hepatocytes. Meanwhile, hepatocyte-specific Setdb1-knockout (Setdb1-HKO) mice exhibited significant lipid accumulation in the liver. Overexpression of Setdb1 was performed with an adenoviral vector through tail vein injection, which ameliorated hepatosteatosis in both Setdb1-HKO and alcoholic diet-fed mice. Mechanistically, downregulated Setdb1 promoted the mRNA expression of Plin2 by desuppressing H3K9me3-mediated chromatin silencing in its upstream sequence. Pin2 acts as a critical membrane surface-associated protein to maintain lipid droplet stability and inhibit lipase degradation. The downregulation of Setdb1 also maintained the stability of Plin2 protein through inhibiting Plin2-recruited chaperone-mediated autophagy (CMA). To explore the reasons for Setdb1 suppression in ALD, we found that upregulated miR-216b-5p bound to the 3'UTR of Setdb1 mRNA, disturbed its mRNA stability, and eventually aggravated hepatic steatosis. CONCLUSIONS: Setdb1 suppression plays an important role in the progression of alcoholic hepatosteatosis via elevating the expression of Plin2 mRNA and maintaining the stability of Plin2 protein. Targeting hepatic Setdb1 might be a promising diagnostic or therapeutic strategy for ALD.
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Background
Acetylcholinesterase (AChE) inhibitors attempt to reduce the breakdown of acetylcholine levels in the brain of patients with Alzheimers disease (AD) by inhibiting the responsible enzyme AChE in the synaptic cleft. This study evaluated the safety, tolerability, and pharmacokinetics of fluoropezil (DC20), a novel AChE inhibitor under development for the treatment of AD in healthy young and elderly Chinese subjects.
Methods
The study on young subjects were divided into two arms: the multiple ascending-dose (MAD) arm (double-blind, randomized, placebo-controlled, multiple ascending-dose, 2 and 6 mg, N = 24), and the food effect arm (three-period, self-crossover, open-labeled, fasting/standard diet/high-fat diet administration, 4 mg, N = 12). A two-period, self-crossover, open-labeled, single ascending-dose study was designed for elderly subjects (2 and 4 mg, N = 11).
Results
For young subjects study: In the MAD arm, the accumulation ratios of DC20 in vivo were 2.29 and 2.15, respectively. In the food effect arm, compared with fasting administration, area under the concentrationtime curve from zero to t (AUC0-t) orally after a standard diet and high-fat diet slightly increased by about
19% and 29% and the Tmax were delayed by around 1 hour. For elderly subjects study, Tmax were 1.5 and 1.25 hour, t1/2 were 77.1 and 74.2 hour, respectively. After oral administration of DC20 in healthy young and elderly subjects, no serious adverse events occurred, the most common adverse events associated with the study drug were gastrointestinal reactions.
Conclusion
We predicted the safety risks of DC20 in the clinical treatment of AD, which were well tolerated by the healthy young and elderly subjects. The elimination of DC20 from the body was slower in elderly subjects than in young subjects.
Title: Characterization and functional analysis of two acetylcholinesterase genes in Bradysia odoriphaga Yang et Zhang (Diptera: Sciaridae) Ding Q, Xu X, Wang X, Ullah F, Gao X, Song D Ref: Pestic Biochem Physiol, 174:104807, 2021 : PubMed
Two acetylcholinesterase genes (Boace1 and Boace2) were cloned from Bradysia odoriphaga, a devastating soil pest that mainly damages Chinese chives. The Boace1 encodes BoAChE1 protein consisting of 696 amino acid residues, while Boace2 encodes BoAChE2 containing 638 amino acids. Phylogenetic analysis showed that Boace1 and Boace2 are appeared to be distinct clusters. The gene expression patterns at different development stages and various body parts tissues were examined, and their biological functions were characterized by RNA interference and analog docking prediction. The results showed that both Boace genes were expressed in all developmental stages and examined tissues. The transcript level of Boace2 was significantly higher than Boace1 in all tested samples, and Boace1 was found most abundant in the head while Boace2 was highly expressed in the fat body of B. odoriphaga. The silencing of Boace1 and Boace2 significantly decreased the AChE activity of 36.6% and 14.8% separately, and increased the susceptibility of B. odoriphaga to phoxim, with 60.8% and 44.7% mortality. Besides, overexpression and gene duplication of Boace1 were found in two field resistant populations, and two major mutations, A319S and G400V, were detected in Boace1. Moreover, the docking results revealed that BoAChE1 had a higher affinity towards organophosphorus than BoAChE2. It is concluded that Boace2 is the most abundant ace type in B. odoriphaga, while both Boace play vital roles. Boace1 might play a major neurological function and more likely be the prime target for insecticides, while Boace2 might play some important unidentified roles.
Title: Characterization of the insecticide detoxification carboxylesterase Boest1 from Bradysia odoriphaga Yang et Zhang (Diptera:Sciaridae) Ding Q, Xu X, Sang Z, Wang R, Ullah F, Gao X, Song D Ref: Pest Manag Sci, :, 2021 : PubMed
BACKGROUND: In insects, carboxylesterases (CarEs) are enzymes involved in the detoxification of insecticides. However, the molecular mechanism of CarE-mediated insecticide metabolism in Bradysia odoriphaga, a serious agricultural pest, remains unclear. The aim of this study is to investigate the detoxification process of malathion, bifenthrin, and imidacloprid by B. odoriphaga carboxylesterase (Boest1). RESULTS: An alpha class CarE gene Boest1 was cloned from B. odoriphaga. The results of real-time quantitative PCR showed that Boest1 is up-regulated with age during the larval stage, and the level of transcription of Boest1 is higher in the midgut and Malpighian tubule than in other tissues. The expression level of Boest1 was significantly increased after exposure to malathion and bifenthrin. Recombinant BoEST1 expressed in vitro showed high catalytic activity toward alpha-naphthyl acetate, which was substantially inhibited by malathion and triphenyl phosphate. The in vitro metabolism assays showed that BoEST1 demonstrates hydrolytic capacity toward malathion and bifenthrin but not imidacloprid. The binding free energy analysis indicates that BoEST1 has a higher affinity for malathion and bifenthrin than imidacloprid. CONCLUSION: These results suggest that BoEST1 plays a role in the breakdown of insecticides and may be involved in the development of resistance in the Chinese chive pest B. odoriphaga; our findings also provide data for better pest management and perspectives for new pesticides development. This article is protected by copyright. All rights reserved.
Title: Pharmacological Activity, Pharmacokinetics, and Toxicity of Timosaponin AIII, a Natural Product Isolated From Anemarrhena asphodeloides Bunge: A Review Lin Y, Zhao WR, Shi WT, Zhang J, Zhang KY, Ding Q, Chen XL, Tang JY, Zhou ZY Ref: Front Pharmacol, 11:764, 2020 : PubMed
Anemarrhena asphodeloides Bunge is a famous Chinese Materia Medica and has been used in traditional Chinese medicine for more than two thousand years. Steroidal saponins are important active components isolated from A. asphodeloides Bunge. Among which, the accumulation of numerous experimental studies involved in Timosaponin AIII (Timo AIII) draws our attention in the recent decades. In this review, we searched all the scientific literatures using the key word "timosaponin AIII" in the PubMed database update to March 2020. We comprehensively summarized the pharmacological activity, pharmacokinetics, and toxicity of Timo AIII. We found that Timo AIII presents multiple-pharmacological activities, such as anti-cancer, anti-neuronal disorders, anti-inflammation, anti-coagulant, and so on. And the anti-cancer effect of Timo AIII in various cancers, especially hepatocellular cancer and breast cancer, is supposed as its most potential activity. The anti-inflammatory activity of Timo AIII is also beneficial to many diseases. Moreover, VEGFR, X-linked inhibitor of apoptosis protein (XIAP), B-cell-specific Moloney murine leukemia virus integration site 1 (BMI1), thromboxane (Tx) A2 receptor, mTOR, NF-kappaB, COX-2, MMPs, acetylcholinesterase (AChE), and so on are identified as the crucial pharmacological targets of Timo AIII. Furthermore, the hepatotoxicity of Timo AIII was most concerned, and the pharmacokinetics and toxicity of Timo AIII need further studies in diverse animal models. In conclusion, Timo AIII is potent as a compound or leading compound for further drug development while still needs in-depth studies.
Title: Observation of Acetylcholinesterase in Stress-Induced Depression Phenotypes by Two-Photon Fluorescence Imaging in the Mouse Brain Wang X, Li P, Ding Q, Wu C, Zhang W, Tang B Ref: Journal of the American Chemical Society, 141:2061, 2019 : PubMed
Oxidative stress in depression is a prime cause of neurotransmitter metabolism dysfunction in the brain. Acetylcholinesterase (AChE), a key hydrolase in the cholinergic system, directly determines the degradation of neurotransmitters. However, due to the complexity of the brain and lack of appropriate in situ imaging tools, the mechanism underlying the changes in AChE activity in depression remains unclear. Hence, we generated a two-photon fluorescence probe (MCYN) for real-time visualization of AChE with excellent sensitivity and selectivity. AChE can specifically recognize and cleave the carbamic acid ester bond in MCYN, and MCYN emits bright fluorescence at 560 nm by two-photon excitation at 800 nm. By utilizing MCYN to monitor AChE, we discovered a significant increase in AChE activity in the brains of mice with depression phenotypes. Notably, with the assistance of a two-photon fluorescence imaging probe of the superoxide anion radical (O2(*-)), in vivo visualization for the first time revealed the positive correlation between AChE and O2(*-) levels associated with depressive behaviors. This finding suggests that oxidative stress may induce AChE overactivation, leading to depression-related behaviors. This work provides a new and rewarding perspective to elucidate the role of oxidative stress regulating AChE in the pathology of depression.
Title: Mechanism hypotheses for the electrophysiological manifestations of two cases of endplate acetylcholinesterase deficiency related congenital myasthenic syndrome Ding Q, Shen D, Dai Y, Hu Y, Guan Y, Liu M, Cui L Ref: J Clin Neurosci, 48:229, 2018 : PubMed
OBJECTIVE: To summarize the electrophysiological characteristics of two cases of endplate acetylcholinesterase deficiency (EAD) related congenital myasthenic syndrome (CMS) caused by COLQ mutation and to discuss the possible mechanism of these electrophysiological phenomena. METHODS: Electrophysiological examinations were conducted including nerve conduction studies, routine electromyography (EMG), repetitive nerve stimulation (RNS) and single fiber EMG (SFEMG). The ulnar nerve was also stimulated at 50Hz followed by 0.5Hz to record the recovery process of compound muscle action potential (CMAP). RESULTS: Repetitive CMAP (R-CMAP) was found in motor nerve conduction in both cases. Needle EMG showed myogenic damages and SFEMG showed remarkably increased jitter values. Of note, the amplitude of CMAP and R-CMAP showed regular changing trends, and so did their time intervals in RNS studies. CONCLUSIONS: The change patterns of CMAP and R-CMAP, in combination with other electrophysiological features are very useful for the diagnosis of EAD related CMS, especially in predicting the presence of correct gene mutations.
The organophosphate-induced delayed neuropathy (OPIDN), often leads to paresthesias, ataxia and paralysis, occurs in the late-stage of acute poisoning or after repeated exposures to organophosphate (OP) insecticides or nerve agents, and may contribute to the Gulf War Syndrome. The acute phase of OP poisoning is often attributed to acetylcholinesterase inhibition. However, the underlying mechanism for the delayed neuropathy remains unknown and no treatment is available. Here we demonstrate that TRPA1 channel (Transient receptor potential cation channel, member A1) mediates OPIDN. A variety of OPs, exemplified by malathion, activates TRPA1 but not other neuronal TRP channels. Malathion increases the intracellular calcium levels and upregulates the excitability of mouse dorsal root ganglion neurons in vitro. Mice with repeated exposures to malathion also develop local tissue nerve injuries and pain-related behaviors, which resembles OPIDN. Both the neuropathological changes and the nocifensive behaviors can be attenuated by treatment of TRPA1 antagonist HC030031 or abolished by knockout of Trpa1 gene. In the classic hens OPIDN model, malathion causes nerve injuries and ataxia to a similar level as the positive inducer tri-ortho-cresyl phosphate (TOCP), which also activates TRPA1 channel. Treatment with HC030031 reduces the damages caused by malathion or tri-ortho-cresyl phosphate. Duloxetine and Ketotifen, two commercially available drugs exhibiting TRPA1 inhibitory activity, show neuroprotective effects against OPIDN and might be used in emergency situations. The current study suggests TRPA1 is the major mediator of OPIDN and targeting TRPA1 is an effective way for the treatment of OPIDN.
Soluble oligomeric amyloid-beta (Abeta) species are toxic to many cell types and are a putative etiological factor in Alzheimer's disease. The NINDS-Custom Collection of 1040 drugs and biologically active compounds was robotically screened for inhibitors of Abeta oligomer formation with a single-site biotinylated Abeta(1-42) oligomer assembly assay. Several quinoline-like compounds were identified with IC(50)'s <10 microM, including the antiprotozoal clioquinol that has been reported to have effects on metal ion metabolism. The 2-OH, 4-OH, and 6-OH quinolines do not block Abeta oligomer formation up to a concentration of 100 microM. Analogs of clioquinol have shown activity in reducing Abeta levels and improving behavioral deficits in mouse models of Abeta pathology. The inhibitory effects of clioquinol and other 8-OH quinoline derivatives on oligomer formation in vitro are unrelated to their chelating activity. Crosslinking studies suggest that clioquinol acts at the stage of trimer formation. These preliminary data may suggest that 8-OH quinolines have the potential for suppressing Abeta oligomer formation which should be considered when assessing the effects of these compounds in animal models and clinical trials.
Title: CSF cholinesterase in early-onset and late-onset Alzheimer's disease and multi-infarct dementia of Chinese patients Shen ZX, Ding Q, Wei CZ, Ding MC, Meng JM Ref: Acta Neurologica Scandinavica, 87:19, 1993 : PubMed
Using Ellman spectrophotometric method we measured the total cholinesterase (ChE) activity in lumbar cerebrospinal fluid (CSF) of 13 persons without neurological disorder, 10 non-demented patients with cerebral infarcts, 17 patients with dementia of Alzheimer's type (DAT) (11 presenile, 6 senile cases), 10 patients with multi-infarct dementia (MID), 1 patient with Parkinson's disease associated with dementia. The ChE activity in CSF was significantly lower in the DAT group compared with age-matched control subjects (p < 0.001). This paper also analyses the possibility of using CSF ChE activity as a marker of DAT, and the relationships between its level of activity and the age of the patient at onset, stage of illness and severity of dementia as well as discrepancies in the data published so far. Previous work has shown that ChE activity in the brain tissue and CSF of MID is normal: therefore, if low ChE activity is found in the CSF of MID patients, as was obtained in 8 out of 10 cases in our series, the diagnosis of mixed dementia should be considered.
