OBJECTIVE The inhibitory effect of active ingredients of Tripterygium wilfordii Hook.F.(TWHF)(celastrol,triptolide,triptonide,wilforlide A,wilforgine and wilforine)on human carboxylester⁃ase 1(CES1)and CES2 was detect...OBJECTIVE The inhibitory effect of active ingredients of Tripterygium wilfordii Hook.F.(TWHF)(celastrol,triptolide,triptonide,wilforlide A,wilforgine and wilforine)on human carboxylester⁃ase 1(CES1)and CES2 was detected to investigate the herb-drug interactions(HDIs)of TWHF.METHODS Human liver microsomes catalysed hydrolysis of 2-(2-benzoyl-3-methoxyphenyl)benzothi⁃azole(BMBT)and fluorescein diacetate(FD)were used as the probe reaction to phenotype the activity of CES1 and CES2,respectively.The residual activities of CES1 and CES2 were detected by ultrahigh performance liquid chromatography(UPLC)after intervention with celastrol,triptolide,triptonide,wilforlide A,wilforgine and wilforine(100μmol·L^(-1)).Kinetics analysis,involving half inhibitory concentra⁃tion(IC_(50)),inhibition type and kinetic parameter(Ki),and in vitro-in vivo extrapolation(IVIVE),was carried out to predict the HDIs between these compounds and CES-metabolizing drugs.Molecular docking was performed to analyze the ligand-enzyme interaction.RESULTS Out of the six main con⁃stituents of TWHF,only celastrol exhibited strong inhibition towards both CES1 and CES2,with the inhibitory rates of 97.45%(P<0.05)and 95.62%(P<0.05),respectively.The IC_(50)was 9.95 and 4.02 mol·L^(-1),respectively,and the types of inhibition were all non-competitive inhibition.Based on the kinetics analysis,the Ki values were calculated to be 5.10 and 10.55μmol·L^(-1)for the inhibition of celastrol on CES1 and CES2,respectively.IVIVE indicated that celastrol might disturb the metabolic hydrolysis of clinical drugs in vivo by inhibiting CES1.Molecular docking results showed that hydrogen bonds and hydrophobic contacts contributed to the interaction of celastrol and CESs.CONCLUSION The inhibitory effect of celastrol on CES1 and CES2 might cause HDIs with clinical drugs hydrolysed by CESs.展开更多
Available online The abnormal carboxylesterase(CES)expression is closely related to many diseases such as hyperlipidemia,atherosclerosis,obesity,liver cancer,type 2 diabetes mellitus and gastrointestinal stromal tumor...Available online The abnormal carboxylesterase(CES)expression is closely related to many diseases such as hyperlipidemia,atherosclerosis,obesity,liver cancer,type 2 diabetes mellitus and gastrointestinal stromal tumors.The detection of a single enzyme in practical samples is often constrained by the structural diversity of CESs.Thus,the development of broad-carboxylesterase responsive fluorescent probe,which can detect the presence of wide variety of CESs,may provide overall or category information from another point of view,supplementing the deficiency of single detection for CES subspecies.Organelle lysosome is involved in various cell processes,such as cell signaling,apoptosis,secretion,and energy metabolism.Up to date,lysosome-targeted fluorescent probes,especially those with red emission(over 550 nm,with relatively low biological harmfulness),for CES detection are still rare.A lysosomes-targeted red fluorescent probe CES-Lyso was designed to monitor intracellular a variety of carboxylesterases alteration with wonderful selectivity and sensitivity,which was further applied to distinguish different derived breast cancer cells and monitor carboxylesterase activity in the anticancer drug treatment.展开更多
Esterases participate in the metabolism of^10%of the clinical drugs that contain ester or amide bonds,but the esterases mediated drug/herb-drug interactions(DDIs or HDIs)have not been reviewed in depth.Carboxylesteras...Esterases participate in the metabolism of^10%of the clinical drugs that contain ester or amide bonds,but the esterases mediated drug/herb-drug interactions(DDIs or HDIs)have not been reviewed in depth.Carboxylesterases(CEs),the most abundant esterases expressed in the metabolic organ of mammals,play a pivotal role in hydrolysis of a variety of endogenous and xenobiotic esters.In the human body,two predominant carboxylesterases including hCE1 and hCE2 have been identified and extensively studied over the past decade.These two enzymes have been found with hydrolytic activity towards a variety of endogenous esters and ester-containing drugs.Recent studies have demonstrated that strong inhibition on hCEs may slow down the hydrolysis of CEs substrates,which may affect their pharmacokinetic properties and thus trigger potential DDIs or HDIs.Over the past decade,many herbal extracts and herbal constitutes have been found with strong inhibitory effects against CEs,and their potential risks on herb-drug interactions(HDIs)have also attracted much attention.This review focused on recent progress in hCEs mediated herb-drug interactions.The roles of hCEs in drug metabolism,the inhibitory capacities and inhibition mechanism of a variety of herbal extract and herbal constitutes against hCEs have been well summarized.Furthermore,the challenges and future perspectives in this field are highlighted by the authors.All information and knowledge presented in this review will be very helpful for the pharmacologists to deeper understand the metabolic interactions between herbal constituents and hCEs,as well as for clinical clinicians to reasonable use herbal medicines for alleviating hCEs-associated drug toxicity or avoiding the occurrence of clinically relevant hCEs-mediated HDIs.展开更多
cis-Diamminedichloroplatinum(CDDP)is widely used for the treatment of various solid cancers.Here we reported that CDDP increased the expression and enzymatic activities of carboxylesterase 1(CES1)and carboxylesterase ...cis-Diamminedichloroplatinum(CDDP)is widely used for the treatment of various solid cancers.Here we reported that CDDP increased the expression and enzymatic activities of carboxylesterase 1(CES1)and carboxylesterase 2(CES2),along with the upregulation of pregnane X receptor(PXR)and the downregulation of differentiated embryonic chondrocyte-expressed gene 1(DEC1)in human hepatoma cells,primary mouse hepatocytes,mouse liver and intestine.The overexpression or knockdown of PXR alone upregulated or downregulated the CES1 and CES2 expression,respectively.The increases in CES1 and CES2 expression levels induced by CDDP abolished or enhanced by PXR knockdown or overexpression,implying that CDDP induces carboxylesterases through the activation of PXR.Likewise,the overexpression or knockdown of DEC1 alone significantly decreased or increased PXR and its targets.Moreover,the increases of PXR and its targets induced by CDDP were abolished or alleviated by the overexpression or knockdown of DEC1.The overexpression or knockdown of DEC1 affected the response of PXR to CDDP,but not vice versa,suggesting that CDDP increases carboxylesterases by upregulating PXR mediated by the decrease of DEC1.In addition,CDDP did not increase DEC1 mRNA degradation but suppressed DEC1 promoter reporter activity,indicating that it suppresses DEC1 transcriptionally.The combined use of CDDP and irinotecan had a synergistic effect on two cell lines,especially when CDDP was used first.展开更多
Mammalian carboxylesterases(CEs) are key enzymes from the serine hydrolase superfamily.In the human body, two predominant carboxylesterases(CES1 and CES2) have been identified and extensively studied over the past dec...Mammalian carboxylesterases(CEs) are key enzymes from the serine hydrolase superfamily.In the human body, two predominant carboxylesterases(CES1 and CES2) have been identified and extensively studied over the past decade. These two enzymes play crucial roles in the metabolism of a wide variety of endogenous esters, ester-containing drugs and environmental toxicants. The key roles of CES in both human health and xenobiotic metabolism arouse great interest in the discovery of potent CES modulators to regulate endobiotic metabolism or to improve the efficacy of ester drugs. This review covers the structural and catalytic features of CES, tissue distributions, biological functions, genetic polymorphisms, substrate specificities and inhibitor properties of CES1 and CES2, as well as the significance and recent progress on the discovery of CES modulators. The information presented here will help pharmacologists explore the relevance of CES to human diseases or to assign the contribution of certain CES in xenobiotic metabolism. It will also facilitate medicinal chemistry efforts to design prodrugs activated by a given CES isoform, or to develop potent and selective modulators of CES for potential biomedical applications.展开更多
Tea flavor is a comprehensive representation of its aroma and other characteristics.The formation of volatile odor compounds during tea processing depends on a variety of enzymatic and non-enzymatic activities.(Z)-3-h...Tea flavor is a comprehensive representation of its aroma and other characteristics.The formation of volatile odor compounds during tea processing depends on a variety of enzymatic and non-enzymatic activities.(Z)-3-hexenol is considered the primary source of the green odor and is also the most important component in tea aroma,significantly affecting the overall aroma.However,the biosynthesis and accumulation of(Z)-3-hexenol during tea processing have not been fully analyzed.In this study,we found that withering treatment at different times and withering plus shaking treatment at different degrees promoted the accumulation of important volatile components of green tea odor,especially(Z)-3-hexenol by GC-MS.The RNA-seq and qRT-PCR results showed that withering and withering plus shaking treatments enhanced the expression of(Z)-3-hexenol-related genes in tea leaves,including synthetic pathway 1 genes(CsLOX3,CsHPL1,CsADH4,and CsAHD1),synthetic pathway 2 genes(CsGLU),and synthetic pathway 3 genes(CsCXEs).Correlation analysis of the key odorants and important genes in the three synthetic pathways revealed that some CsCXEs were positively correlated with green odor compounds.The in vitro enzyme activity results showed that rCsCXE3(GWHTASIV011658),and rCsCXE6(GWHTASIV031480)exhibited hydrolytic activity against three tea acetate compounds[hexyl acetate,(E)-2-hexyl acetate,and(Z)-3-hexyl acetate],resulting in the production of corresponding alcohol compounds.In summary,withering and shaking treatment during tea processing promoted the expression of CsCXE3 and CsCXE6,thereby enhancing the production of hexenol compounds.These compounds play a crucial role in increasing the green odor of tea.展开更多
Mammalian carboxylesterases hydrolyze a wide range of xenobiotic and endogenous compounds, including lipid esters. Physiological functions of car- boxylesterases in lipid metabolism and energy home- ostasis in vivo ha...Mammalian carboxylesterases hydrolyze a wide range of xenobiotic and endogenous compounds, including lipid esters. Physiological functions of car- boxylesterases in lipid metabolism and energy home- ostasis in vivo have been demonstrated by genetic manipulations and chemical inhibition in mice, and in vitro through （over）expression, knockdown of expression, and chemical inhibition in a variety of cells. Recent research advances have revealed the relevance of carboxylesterases to metabolic diseases such as obesity and fatty liver disease, suggesting these enzymes might be potential targets for treatment of metabolic disorders. In order to translate pre-clinical studies in cellular and mouse models to humans, dif- ferences and similarities of carboxylesterases between mice and human need to be elucidated. This review presents and discusses the research progress in structure and function of mouse and human car- boxylesterases, and the role of these enzymes in lipid metabolism and metabolic disorders.展开更多
Carboxylesterases (CarEs) belong to a super family of multifunctional enzymes associated with the degradation of endogenous and exogenous compounds. Many insect CarEs are known to play important roles in catalyzing th...Carboxylesterases (CarEs) belong to a super family of multifunctional enzymes associated with the degradation of endogenous and exogenous compounds. Many insect CarEs are known to play important roles in catalyzing the hydrolysis of organophosphates (OPs), carbamates, and synthetic pyrethroids (SPs). The elevation of esterase activity through gene amplification and overexpression of estα2 and estβ2 genes contributes to the development of resistance to OP insecticides in the mosquito Culex quinquefasciatus. Three additional CarE genes are upregulated in permethrin-resistant Cx. quinquefasciatus according to an RNA-seq analysis, but their function remains unknown. In this study, we, for the first time, characterized the function of these three novel genes using in vitro protein expression, an insecticide metabolism study and molecular docking analysis. All three CarE genes were significantly overexpressed in resistant mosquito larvae, but not adults, compared to susceptible strain. No gene copy differences in these three genes were found in the mosquitoes tested. In vitro high-performance liquid chromatography (HPLC) revealed that CPIJ018231, CPIJ018232, and CPIJ018233 metabolized 30.4% ± 2.9%, 34.7% ± 6.8%, and 23.2% ± 2.2% of the permethrin, respectively. No mutations in resistant strains might significantly affect their CarE hydrolysis ability. A docking analysis further confirmed that these three CarEs from resistant strain all potentially metabolize permethrin. Taken together, these three carboxylesterase genes could play important roles in the development of permethrin resistance in Cx. quinquefasciatus larvae through transcriptional overexpression, metabolism, and detoxification.展开更多
Background:Head and neck squamous cell carcinoma(HNSCC)is a prevalent form of cancer globally,with chemoresistance posing a major challenge in treatment outcomes.The efficacy of the commonly used chemotherapeutic agent...Background:Head and neck squamous cell carcinoma(HNSCC)is a prevalent form of cancer globally,with chemoresistance posing a major challenge in treatment outcomes.The efficacy of the commonly used chemotherapeutic agent,cisplatin,is diminished in patients with poor prognoses.Methods:Various bioinformatics databases were utilized to examine Carboxylesterase 1(CES1)gene expression,clinicopathologic features,patient survival analysis,and gene function.An organoid model of HNSCC was established,along with the induction of drug-resistant HNSCC in the organoid model.CES1 expression was assessed using qRT-PCR and Western Blot,and differential markers were identified through transcriptome sequencing.Knockdown and overexpression models of CES1 were created in SCC-9 and patient-derived organoid(PDO)cells using shRNA and lentivirus to investigate the tumor biology and cisplatin resistance associated with CES1.Results:Research in bioinformatics has uncovered a strong correlation between the expression level of CES1 and the prognosis of HNSCC.The data suggests a significant link between CES1 expression and tobacco smoking.RNA-sequencing revealed a notable increase in CES1 expression in HNSCC-PDOcis-R cells compared to the parental PDO cells.Subsequently,we performed in vitro studies by HNSCC-PDO and SCC-9 and found that CES1-overexpressing cells exhibited reduced sensitivity to cisplatin and stronger tumor malignant biological behavior compared with CES1-knockdown cells.Conclusion:The observed association between CES1 expression and tobacco smoking implies a potential influence of smoking on the efficacy of cisplatin-based chemotherapy in HNSCC through the regulation of CES1 expression.展开更多
[Objective] The research aimed to assess the effect of transgenic Bt plus CpTI cotton variety SGK321 on carboxylesterase and acetylcholinesterase of cotton aphid Aphis gossypii and provide theoretical basis for studyi...[Objective] The research aimed to assess the effect of transgenic Bt plus CpTI cotton variety SGK321 on carboxylesterase and acetylcholinesterase of cotton aphid Aphis gossypii and provide theoretical basis for studying the biosafety of transgenic cotton.[Method] Cotton aphids were fed with SGK321 and Shiyuan321（normal parental varieties） for over 40 generations.Enzyme activities were compared between cotton aphids feeding on SGK321 for 1,2,3,41,42 and 43 generations with those on Shiyuan321.[Result] The carboxylesterase activity of cotton aphids feeding on SGK321 for 1 generation was significantly higher than those feeding on Shiyuan321.Acetylcholinesterase activity of cotton aphids feeding on SGK321 for 1,2 and 3 generations were significantly higher than those feeding on Shiyuan321 in the same generation.But there was no significant difference of enzyme activity between cotton aphids feeding on SGK321 for a long term and those feeding on parental cotton.[Conclusion] The cotton aphid that feeding on transgenic Bt plus CpTI cotton SGK321 for a long time has adaptivity to SGK321 by regulating the detoxifying enzyme.展开更多
Carboxylesterases （CarEs） from two field populations of the oriental migratory locust, Locusta migratoria manilensis （Meyen）, were examined to try to understand their contribution to malathion insensitivity. The C...Carboxylesterases （CarEs） from two field populations of the oriental migratory locust, Locusta migratoria manilensis （Meyen）, were examined to try to understand their contribution to malathion insensitivity. The CarEs activities in Wudi population （WD） were 1.75- and 1.50-fold significantly higher than those in Huangliu population （HL） when a-naphthyl acetate （a-NA） and [3-naphthyl acetate were used as substrates, respectively. Such elevated CarEs activities presented in the WD could be because of an increased staining intensity of the a-NA-hydrolyzing CarEs as shown on the nondenaturing polyacrylamide gel electrophoresis. Inhibition studies of CarEs using paraoxon and malaoxon indicated that CarE activities in the HL were more strongly inhibited than those in the WD. Furthermore, a 449-bp DNA fragment of CarE was obtained from L. migratoria manilensis. Hemiquantity reverse transcription-polymerase chain reaction analysis showed that CarE gene expression level in the WD was higher than that in the HL. The higher CarE activities and the increased CarE mRNA level in the WD appeared to be associated with decreased susceptibility to malathion in the WD due to the application of organophosphorus insecticides.展开更多
Methyl(S)-4-(6-amino-9 H-purin-9-yl)-2-hydroxybutanoate(DZ2002) is a potent reversible inhibitor of S-adenosyl-L-homocysteine hydrolase(SAHH). Due to its ester structure, DZ2002 is rapidly hydrolyzed in rat blood to 4...Methyl(S)-4-(6-amino-9 H-purin-9-yl)-2-hydroxybutanoate(DZ2002) is a potent reversible inhibitor of S-adenosyl-L-homocysteine hydrolase(SAHH). Due to its ester structure, DZ2002 is rapidly hydrolyzed in rat blood to 4-(6-amino-9 H-purin-9-yl)-2-hydroxybutyric acid(DZA) during and after blood sampling from rats; this hampers accurate determination of the circulating DZ2002 and its acid metabolite DZA in rats. To this end, a method for determining the blood concentrations of DZ2002 and DZA in rats was developed by using methanol to immediately deactivate blood carboxylesterases during sampling. The newly developed bioanalytical assay possessed favorable accuracy and precision with lower limit of quantification of 31 nM for DZ2002 and DZA. This validated assay was applied to a rat pharmacokinetic study of DZ2002. After oral administration, DZ2002 was found to be extensively converted into DZA. The level of systemic exposure to DZ2002 was significantly lower than that of DZA. The apparent oral bioavailability of DZ2002 was 90%–159%. The mean terminal half-lives of DZ2002 and DZA were 0.3–0.9 and 1.3–5.1 h, respectively. The sample preparation method illustrated here may be adopted for determination of other circulating ester drugs and their acid metabolites in rodents.展开更多
Carboxylesterases (CESs) play important roles in the metabolism of endogenous and foreign compounds in physiological and pharmacological responses. The aim of this study was to investigate the effect of dexamethasone ...Carboxylesterases (CESs) play important roles in the metabolism of endogenous and foreign compounds in physiological and pharmacological responses. The aim of this study was to investigate the effect of dexamethasone at different doses on the expression of CES1 and CES2. Imidapril and irinotecan hydrochloride (CPT-11) were used as special substrates for CES1 and CES2, respectively. Rat hepatocytes were cultured and treated with different concentrations of dexamethasone. The hydrolytic activity of CES1 and CES2 was tested by incubation experiment and their expression was quantitated by real-time PCR. A pharmacokinetic study was conducted in SD rats to further evaluate the effect of dexamethasone on CESs activity in vivo. Western blotting was performed to investigate the regulatory mechanism related to pregnane X receptor (PXR) and glucocorticoid receptor (GR). The results showed that exposure of cultured rat hepatocytes to nanomolar dexamethasone inhibited the imidapril hydrolase activity, which was slightly elevated by micromolar dexamethasone. For CES2, CPT-11 hydrolase activity was induced only when dexamethasone reached micromolar levels. The real-time PCR demonstrated that CES1 mRNA was markedly decreased by nanomolar dexamethasone and increased by micromolar dexamethasone, whereas CES2 mRNA was significantly increased by micromolar dexamethasone. The results of a complementary animal study showed that the concurrent administration of dexamethasone significantly increased the plasma concentration of the metabolite of imidapril while the ratio of CPT-11 to its metabolite SN-38 was significantly decreased. PXR protein was gradually increased by serial concentrations of dexamethasone. However, only nanomolar dexamethasone elevated the level of GR protein. The different concentrations of dexamethasone required suggested that suppression of CES1 may be mediated by GR whereas the induction of CES2 may result from the role of PXR. It was concluded that dexamethasone at different concentrations can differentially regulate CES1 and CES2.展开更多
Infectious pandemics result in hundreds and millions of deaths,notable examples of the Spanish Flu,the Black Death and smallpox.The current pandemic,caused by SARS-CoV-2(severe acute respiratory syndrome coronavirus 2...Infectious pandemics result in hundreds and millions of deaths,notable examples of the Spanish Flu,the Black Death and smallpox.The current pandemic,caused by SARS-CoV-2(severe acute respiratory syndrome coronavirus 2),is unprecedented even in the historical term of pandemics.The unprecedentedness is featured by multiple surges,rapid identification of therapeutic options and accelerated development of vaccines.Remdesivir,originally developed for Ebola viral disease,is the first treatment of COVID-19(Coronavirus disease 2019)approved by the United States Food and Drug Administration.As demonstrated by in vitro and preclinical studies,this therapeutic agent is highly potent with a broad spectrum activity against viruses from as many as seven families even cross species.However,randomized controlled trials have failed to confirm the efficacy and safety.Remdesivir improves some clinical signs but not critical parameters such as mortality.This antiviral agent is an ester/phosphorylation prodrug and excessive hydrolysis which increases cellular toxicity.Remdesivir is given intravenously,leading to concentration spikes and likely increasing the potential of hydrolysis-based toxicity.This review has proposed a conceptual framework for improving its efficacy and minimizing toxicity not only for the COVID-19 pandemic but also for future ones caused by remdesivir-sensitive viruses.展开更多
The melon aphid, Aphis gossypii Glover (Hemiptera: Aphididae), is a highly polyphagous sap sucking pest on wide varieties of crops including cotton and vegetables. It is a notorious vector of many plant viruses that a...The melon aphid, Aphis gossypii Glover (Hemiptera: Aphididae), is a highly polyphagous sap sucking pest on wide varieties of crops including cotton and vegetables. It is a notorious vector of many plant viruses that are persistently and non-persistently transmitted. In nature, aphids are regulated by their natural enemies. However, chemical control remains a major management tool even though resistance to insecticides has been documented worldwide. A better understanding of mechanisms by which insecticide resistance occurs and its early detection is desirable to develop effective management strategies. The present investigation was conducted to study the development of resistance to an organophosphate (OP) compound-dimethoate, identify biochemical mechanism(s) involved in resistance and study cross-resistance to imidacloprid in laboratory selected A. gossypii strains in comparison to susceptible strains. Bioassay studies revealed that the LC50 values increased dramatically with dimethoate selection in resistant strains and the resistance ratio (RR) was 270-, 243- and 210-fold greater than that of the susceptible strains by 30th generation. Further, biochemical assays revealed enhanced activities of carboxylesterases (CarE), glutathione S-transferases (GSTs) and cytochrome P450-mediated p-Nitroanisole O-demethylase (PNOD) in resistant strains supporting their role in dimethoate detoxification. This study thus revealed that enhanced activity of detoxifying enzymes viz., CarE, GSTs and PNODs is one of the mechanisms underlying dimethoate resistance in A. gossypii collected from South India. Interestingly, the possibility of negatively correlated cross-resistance to imidacloprid was identified in three OP- resistant strains exhibiting 2.97-, 2.56- and 3.76-fold sensitivity to imidacloprid (a novel neonicotinoid). This indicated that the latter was less affected by the resistance mechanism(s) present.展开更多
The melon aphid, <i>Aphis gossypii</i> Glover (Hemiptera: Aphididae), is a highly polyphagous sap sucking pest on wide varieties of crops including cotton and vegetables. It is a notorious vector of many p...The melon aphid, <i>Aphis gossypii</i> Glover (Hemiptera: Aphididae), is a highly polyphagous sap sucking pest on wide varieties of crops including cotton and vegetables. It is a notorious vector of many plant viruses that are persistently and non-persistently transmitted. In nature, aphids are regulated by their natural enemies. However, chemical control remains a major management tool even though resistance to insecticides has been documented worldwide. A better understanding of mechanisms by which insecticide resistance occurs and its early detection is desirable to develop effective management strategies. The present investigation was conducted to study the development of resistance to an organophosphate (OP) compound-dimethoate, identify biochemical mechanism(s) involved in resistance and study cross-resistance to imidacloprid in laboratory selected <i>A. gossypii</i> strains in comparison to susceptible strains. Bioassay studies revealed that the LC50 values increased dramatically with dimethoate selection in resistant strains and the resistance ratio (RR) was 270-, 243- and 210-fold greater than that of the susceptible strains by 30th generation. Further, biochemical assays revealed enhanced activities of carboxylesterases (CarE), glutathione S-transferases (GSTs) and cytochrome P450-mediated <i>p</i>-Nitroanisole <i>O</i>-demethylase (PNOD) in resistant strains supporting their role in dimethoate detoxification. This study thus revealed that enhanced activity of detoxifying enzymes <i>viz</i>., CarE, GSTs and PNODs is one of the mechanisms underlying dimethoate resistance in <i>A. gossypii</i> collected from South India. Interestingly, the possibility of negatively correlated cross-resistance to imidacloprid was identified in three OP- resistant strains exhibiting 2.97-, 2.56- and 3.76-fold sensitivity to imidacloprid (a novel neonicotinoid). This indicated that the latter was less affected by the resistance mechanism(s) present.展开更多
Background: T-2 toxin poses a great threat to human health because it has the highest toxicity of the currently known trichothecene mycotoxins. To understand the in vivo toxicity and transformation mechanism of T-2 to...Background: T-2 toxin poses a great threat to human health because it has the highest toxicity of the currently known trichothecene mycotoxins. To understand the in vivo toxicity and transformation mechanism of T-2 toxin, we investigated the role of two principal phase Ⅰ drug-metabolizing enzymes(cytochrome P450 [CYP450] enzymes) on the metabolism of T-2 toxin, which are crucial to the metabolism of endogenous substances and xenobiotics. We also investigated carboxylesterase, which also plays an important role in the metabolism of toxic substances.Methods: A chemical inhibition method and a recombinant method were employed to investigate the metabolism of the T-2 toxin by the CYP450 enzymes, and a chemical inhibition method was used to study carboxylesterase metabolism. Samples incubated with human liver microsomes were analyzed by high performance liquid chromatography-triple quadrupole mass spectrometry(HPLC- Qq Q MS) after a simple pretreatment.Results: In the presence of a carboxylesterase inhibitor, only 20% T-2 toxin was metabolized. When CYP enzyme inhibitors and a carboxylesterase inhibitor were both present, only 3% of the T-2 toxin was metabolized. The contributions of the CYP450 enzyme family to T-2 toxin metabolism followed the descending order CYP3A4, CYP2E1, CYP1A2, CYP2B6 or CYP2D6 or CYP2C19.Conclusions: Carboxylesterase and CYP450 enzymes are of great importance in T-2 toxin metabolism, in which carboxylesterase is predominant and CYP450 has a subordinate role. CYP3A4 is the principal member of the CYP450 enzyme family responsible for T-2 toxin metabolism. The metabolite produced by carboxylesterase is HT-2, and the metabolite produced by CYP 3A4 is 3'-OH T-2. The different metabolites show different toxicities. Our results will provide useful data concerning the toxic mechanism, the safety evaluation, and the health risk assessment of T-2 toxin.展开更多
Despite the fact that the phenomenon of capacitation was discovered over half century ago and much progress has been made in identifying sperm events involved in capacitation, few specific molecules of epididymal orig...Despite the fact that the phenomenon of capacitation was discovered over half century ago and much progress has been made in identifying sperm events involved in capacitation, few specific molecules of epididymal origin have been identified as being directly involved in this process in vivo. Previously, our group cloned and characterized a carboxyl esterase gene CesSa in the rat epididymis. The CES5A protein is mainly expressed in the corpus and cauda epididymidis and secreted into the corresponding lumens. Here, we report the function of CESSA in sperm maturation. By local injection of Lentivirus-mediated siRNA in the CESSA.expressing region of the rat epididymis, CesSa-knockdown animal models were created. These animals exhibited an inhibited sperm capacitation and a reduction in male fertility. These results suggest that CESSA plays an important role in sperm maturation and male fertility.展开更多
Carboxylesterase 1(CES1), one of the most abundant serine hydrolases in mammals, has drawn much attentions in recent years, owing to this enzyme involves in many physiological processes via hydrolysis of both endogeno...Carboxylesterase 1(CES1), one of the most abundant serine hydrolases in mammals, has drawn much attentions in recent years, owing to this enzyme involves in many physiological processes via hydrolysis of both endogenous esters and xenobiotic esters. Herein, to real-time monitor the activities of CES1 in various biological systems, a practical and iso form-specific fluorescent probe was developed on the basis of the substrate preference of CES1, as well as the structural and optical properties of BODIPY dyes. After screening of a panel of BODIPY ester derivatives, probe 1 displayed the best combination of specificity,sensitivity, enzymatic kinetics and applicability for monitoring CES1 activities in real samples. This probe was successfully used to detect CESl activities in several biological systems including tissue preparations,living cells, tissue slices and zebrafish. Furthermore, the biomedical applications of probe 1 for screening of CES1 inhibitors were also demonstrated using tissue preparations or living cells as enzyme sources. In summary, a practical and broadly applicable tool for real-time monitoring CES1 in biological systems was developed and well-characterized, which held great promise for further investigations on CES1-associated drug discovery, clinical practice and fundamental research.展开更多
Carboxylesterase(CarE)was considered as important phase-I detoxifying enzymes which participated in detoxification of different types of insecticides.Up-regulation of CarE genes has been proved playing a major role in...Carboxylesterase(CarE)was considered as important phase-I detoxifying enzymes which participated in detoxification of different types of insecticides.Up-regulation of CarE genes has been proved playing a major role in insecticide resistance in many pest insects,but its involvement in resistance to insecticides in Plutella xylostella has been rarely reported.In this study,a CarE cDNA named PxαE8 was identified in P.xylostella,which has an open reading frame of 1599 nucleotides and putatively encodes 532 amino acids.The investigation of spatial expression profiles of PxαE8 revealed that it was expressed in all developmental stages,especially in larvae and adults.The body part/tissue-specific expression profiles showed that the PxαE8 mainly expressed in fat body,malpighian tubule and hemolymph of larvae.Further,the relative expression of PxαE8 in two multi-resistant field populations,Hainan(HN)and Guangdong(GD)populations,was found 24.4-and 15.5-fold higher than that in susceptible population,respectively.Knockdown of PxαE8 by RNA interference dramatically increased the mortalities of larvae of HN population treated with LC_(50) of beta-cypermethrin and phoxim by 25.3 and 18.3%,respectively.These results suggested that up-regulation of PxαE8 was involved in resistance to both beta-cypermethrin and phoxim in P.xylostella,which shed light on further understanding of molecular mechanisms of multi-insecticide-resistance in P.xylostella and other pest insects.展开更多
文摘OBJECTIVE The inhibitory effect of active ingredients of Tripterygium wilfordii Hook.F.(TWHF)(celastrol,triptolide,triptonide,wilforlide A,wilforgine and wilforine)on human carboxylester⁃ase 1(CES1)and CES2 was detected to investigate the herb-drug interactions(HDIs)of TWHF.METHODS Human liver microsomes catalysed hydrolysis of 2-(2-benzoyl-3-methoxyphenyl)benzothi⁃azole(BMBT)and fluorescein diacetate(FD)were used as the probe reaction to phenotype the activity of CES1 and CES2,respectively.The residual activities of CES1 and CES2 were detected by ultrahigh performance liquid chromatography(UPLC)after intervention with celastrol,triptolide,triptonide,wilforlide A,wilforgine and wilforine(100μmol·L^(-1)).Kinetics analysis,involving half inhibitory concentra⁃tion(IC_(50)),inhibition type and kinetic parameter(Ki),and in vitro-in vivo extrapolation(IVIVE),was carried out to predict the HDIs between these compounds and CES-metabolizing drugs.Molecular docking was performed to analyze the ligand-enzyme interaction.RESULTS Out of the six main con⁃stituents of TWHF,only celastrol exhibited strong inhibition towards both CES1 and CES2,with the inhibitory rates of 97.45%(P<0.05)and 95.62%(P<0.05),respectively.The IC_(50)was 9.95 and 4.02 mol·L^(-1),respectively,and the types of inhibition were all non-competitive inhibition.Based on the kinetics analysis,the Ki values were calculated to be 5.10 and 10.55μmol·L^(-1)for the inhibition of celastrol on CES1 and CES2,respectively.IVIVE indicated that celastrol might disturb the metabolic hydrolysis of clinical drugs in vivo by inhibiting CES1.Molecular docking results showed that hydrogen bonds and hydrophobic contacts contributed to the interaction of celastrol and CESs.CONCLUSION The inhibitory effect of celastrol on CES1 and CES2 might cause HDIs with clinical drugs hydrolysed by CESs.
基金the financial support from the National Natural Science Foundation of China (No. 21705120)the Technology Support Project of Shandong Province Higher Educational Youth Innovation (No. 2019KJM008)+1 种基金the Natural Science Foundation of Shandong Province, China (No. ZR2017LB016)the Project of Shandong Province Higher Educational Science and Technology Program (No. J17KB074)
文摘Available online The abnormal carboxylesterase(CES)expression is closely related to many diseases such as hyperlipidemia,atherosclerosis,obesity,liver cancer,type 2 diabetes mellitus and gastrointestinal stromal tumors.The detection of a single enzyme in practical samples is often constrained by the structural diversity of CESs.Thus,the development of broad-carboxylesterase responsive fluorescent probe,which can detect the presence of wide variety of CESs,may provide overall or category information from another point of view,supplementing the deficiency of single detection for CES subspecies.Organelle lysosome is involved in various cell processes,such as cell signaling,apoptosis,secretion,and energy metabolism.Up to date,lysosome-targeted fluorescent probes,especially those with red emission(over 550 nm,with relatively low biological harmfulness),for CES detection are still rare.A lysosomes-targeted red fluorescent probe CES-Lyso was designed to monitor intracellular a variety of carboxylesterases alteration with wonderful selectivity and sensitivity,which was further applied to distinguish different derived breast cancer cells and monitor carboxylesterase activity in the anticancer drug treatment.
基金the National Key Research and Development Program of China(2017YFC1700200,2017YFC1702000)the National Scientific and Technological Major Projects of China(2017ZX09101004)+3 种基金the National Natural Science Foundation of China(81703604,81773687 and 81573501)Program of Shanghai Academic/Technology Research Leader(18XD1403600)Shuguang Program(No.18SG40)Shanghai Education Development Foundation and Shanghai Municipal Education Commission,Project funded by China Postdoctoral Science Foundation(2017M621520,and 2018T110406).
文摘Esterases participate in the metabolism of^10%of the clinical drugs that contain ester or amide bonds,but the esterases mediated drug/herb-drug interactions(DDIs or HDIs)have not been reviewed in depth.Carboxylesterases(CEs),the most abundant esterases expressed in the metabolic organ of mammals,play a pivotal role in hydrolysis of a variety of endogenous and xenobiotic esters.In the human body,two predominant carboxylesterases including hCE1 and hCE2 have been identified and extensively studied over the past decade.These two enzymes have been found with hydrolytic activity towards a variety of endogenous esters and ester-containing drugs.Recent studies have demonstrated that strong inhibition on hCEs may slow down the hydrolysis of CEs substrates,which may affect their pharmacokinetic properties and thus trigger potential DDIs or HDIs.Over the past decade,many herbal extracts and herbal constitutes have been found with strong inhibitory effects against CEs,and their potential risks on herb-drug interactions(HDIs)have also attracted much attention.This review focused on recent progress in hCEs mediated herb-drug interactions.The roles of hCEs in drug metabolism,the inhibitory capacities and inhibition mechanism of a variety of herbal extract and herbal constitutes against hCEs have been well summarized.Furthermore,the challenges and future perspectives in this field are highlighted by the authors.All information and knowledge presented in this review will be very helpful for the pharmacologists to deeper understand the metabolic interactions between herbal constituents and hCEs,as well as for clinical clinicians to reasonable use herbal medicines for alleviating hCEs-associated drug toxicity or avoiding the occurrence of clinically relevant hCEs-mediated HDIs.
基金The work was supported by the National Natural Science Foundation of China(Grant Nos.82073934 and 81872937)to J.Y.
文摘cis-Diamminedichloroplatinum(CDDP)is widely used for the treatment of various solid cancers.Here we reported that CDDP increased the expression and enzymatic activities of carboxylesterase 1(CES1)and carboxylesterase 2(CES2),along with the upregulation of pregnane X receptor(PXR)and the downregulation of differentiated embryonic chondrocyte-expressed gene 1(DEC1)in human hepatoma cells,primary mouse hepatocytes,mouse liver and intestine.The overexpression or knockdown of PXR alone upregulated or downregulated the CES1 and CES2 expression,respectively.The increases in CES1 and CES2 expression levels induced by CDDP abolished or enhanced by PXR knockdown or overexpression,implying that CDDP induces carboxylesterases through the activation of PXR.Likewise,the overexpression or knockdown of DEC1 alone significantly decreased or increased PXR and its targets.Moreover,the increases of PXR and its targets induced by CDDP were abolished or alleviated by the overexpression or knockdown of DEC1.The overexpression or knockdown of DEC1 affected the response of PXR to CDDP,but not vice versa,suggesting that CDDP increases carboxylesterases by upregulating PXR mediated by the decrease of DEC1.In addition,CDDP did not increase DEC1 mRNA degradation but suppressed DEC1 promoter reporter activity,indicating that it suppresses DEC1 transcriptionally.The combined use of CDDP and irinotecan had a synergistic effect on two cell lines,especially when CDDP was used first.
基金supported by the National Key Research and Development Program of China (2016YFC1303900,2017YFC1700200,2017YFC1702000)the National Scientific and Technological Major Projects of China (2017ZX09101004)+2 种基金the National Natural Science Foundation of China (81703604,81773687,21602219,81573501 and 81473181)Program of Shanghai Academic/Technology Research Leader (18XD1403600)the Innovative Entrepreneurship Program of High-level Talents in Dalian (2016RQ025)
文摘Mammalian carboxylesterases(CEs) are key enzymes from the serine hydrolase superfamily.In the human body, two predominant carboxylesterases(CES1 and CES2) have been identified and extensively studied over the past decade. These two enzymes play crucial roles in the metabolism of a wide variety of endogenous esters, ester-containing drugs and environmental toxicants. The key roles of CES in both human health and xenobiotic metabolism arouse great interest in the discovery of potent CES modulators to regulate endobiotic metabolism or to improve the efficacy of ester drugs. This review covers the structural and catalytic features of CES, tissue distributions, biological functions, genetic polymorphisms, substrate specificities and inhibitor properties of CES1 and CES2, as well as the significance and recent progress on the discovery of CES modulators. The information presented here will help pharmacologists explore the relevance of CES to human diseases or to assign the contribution of certain CES in xenobiotic metabolism. It will also facilitate medicinal chemistry efforts to design prodrugs activated by a given CES isoform, or to develop potent and selective modulators of CES for potential biomedical applications.
基金supported by the Natural Science Foundation of China(Grant Nos.U21A2023 and 32072621)the earmarked fund for CARS-19 and the Youth Science and Technology Talents Support Program(2020)by Anhui Association for Science and Technology(Grant No.RCTJ202010).
文摘Tea flavor is a comprehensive representation of its aroma and other characteristics.The formation of volatile odor compounds during tea processing depends on a variety of enzymatic and non-enzymatic activities.(Z)-3-hexenol is considered the primary source of the green odor and is also the most important component in tea aroma,significantly affecting the overall aroma.However,the biosynthesis and accumulation of(Z)-3-hexenol during tea processing have not been fully analyzed.In this study,we found that withering treatment at different times and withering plus shaking treatment at different degrees promoted the accumulation of important volatile components of green tea odor,especially(Z)-3-hexenol by GC-MS.The RNA-seq and qRT-PCR results showed that withering and withering plus shaking treatments enhanced the expression of(Z)-3-hexenol-related genes in tea leaves,including synthetic pathway 1 genes(CsLOX3,CsHPL1,CsADH4,and CsAHD1),synthetic pathway 2 genes(CsGLU),and synthetic pathway 3 genes(CsCXEs).Correlation analysis of the key odorants and important genes in the three synthetic pathways revealed that some CsCXEs were positively correlated with green odor compounds.The in vitro enzyme activity results showed that rCsCXE3(GWHTASIV011658),and rCsCXE6(GWHTASIV031480)exhibited hydrolytic activity against three tea acetate compounds[hexyl acetate,(E)-2-hexyl acetate,and(Z)-3-hexyl acetate],resulting in the production of corresponding alcohol compounds.In summary,withering and shaking treatment during tea processing promoted the expression of CsCXE3 and CsCXE6,thereby enhancing the production of hexenol compounds.These compounds play a crucial role in increasing the green odor of tea.
文摘Mammalian carboxylesterases hydrolyze a wide range of xenobiotic and endogenous compounds, including lipid esters. Physiological functions of car- boxylesterases in lipid metabolism and energy home- ostasis in vivo have been demonstrated by genetic manipulations and chemical inhibition in mice, and in vitro through （over）expression, knockdown of expression, and chemical inhibition in a variety of cells. Recent research advances have revealed the relevance of carboxylesterases to metabolic diseases such as obesity and fatty liver disease, suggesting these enzymes might be potential targets for treatment of metabolic disorders. In order to translate pre-clinical studies in cellular and mouse models to humans, dif- ferences and similarities of carboxylesterases between mice and human need to be elucidated. This review presents and discusses the research progress in structure and function of mouse and human car- boxylesterases, and the role of these enzymes in lipid metabolism and metabolic disorders.
基金The project described was supported by the following awards:AAES Hatch/Multistate Grants ALA08-045,ALA015-1-10026,ALA015-1-16009 to NL.
文摘Carboxylesterases (CarEs) belong to a super family of multifunctional enzymes associated with the degradation of endogenous and exogenous compounds. Many insect CarEs are known to play important roles in catalyzing the hydrolysis of organophosphates (OPs), carbamates, and synthetic pyrethroids (SPs). The elevation of esterase activity through gene amplification and overexpression of estα2 and estβ2 genes contributes to the development of resistance to OP insecticides in the mosquito Culex quinquefasciatus. Three additional CarE genes are upregulated in permethrin-resistant Cx. quinquefasciatus according to an RNA-seq analysis, but their function remains unknown. In this study, we, for the first time, characterized the function of these three novel genes using in vitro protein expression, an insecticide metabolism study and molecular docking analysis. All three CarE genes were significantly overexpressed in resistant mosquito larvae, but not adults, compared to susceptible strain. No gene copy differences in these three genes were found in the mosquitoes tested. In vitro high-performance liquid chromatography (HPLC) revealed that CPIJ018231, CPIJ018232, and CPIJ018233 metabolized 30.4% ± 2.9%, 34.7% ± 6.8%, and 23.2% ± 2.2% of the permethrin, respectively. No mutations in resistant strains might significantly affect their CarE hydrolysis ability. A docking analysis further confirmed that these three CarEs from resistant strain all potentially metabolize permethrin. Taken together, these three carboxylesterase genes could play important roles in the development of permethrin resistance in Cx. quinquefasciatus larvae through transcriptional overexpression, metabolism, and detoxification.
基金supported by the National Natural Science Foundation of China(No.82160386)the Guangxi Natural Science Foundation of China(No.2024GXNSFDA010032,2023GXNSFAA026189).
文摘Background:Head and neck squamous cell carcinoma(HNSCC)is a prevalent form of cancer globally,with chemoresistance posing a major challenge in treatment outcomes.The efficacy of the commonly used chemotherapeutic agent,cisplatin,is diminished in patients with poor prognoses.Methods:Various bioinformatics databases were utilized to examine Carboxylesterase 1(CES1)gene expression,clinicopathologic features,patient survival analysis,and gene function.An organoid model of HNSCC was established,along with the induction of drug-resistant HNSCC in the organoid model.CES1 expression was assessed using qRT-PCR and Western Blot,and differential markers were identified through transcriptome sequencing.Knockdown and overexpression models of CES1 were created in SCC-9 and patient-derived organoid(PDO)cells using shRNA and lentivirus to investigate the tumor biology and cisplatin resistance associated with CES1.Results:Research in bioinformatics has uncovered a strong correlation between the expression level of CES1 and the prognosis of HNSCC.The data suggests a significant link between CES1 expression and tobacco smoking.RNA-sequencing revealed a notable increase in CES1 expression in HNSCC-PDOcis-R cells compared to the parental PDO cells.Subsequently,we performed in vitro studies by HNSCC-PDO and SCC-9 and found that CES1-overexpressing cells exhibited reduced sensitivity to cisplatin and stronger tumor malignant biological behavior compared with CES1-knockdown cells.Conclusion:The observed association between CES1 expression and tobacco smoking implies a potential influence of smoking on the efficacy of cisplatin-based chemotherapy in HNSCC through the regulation of CES1 expression.
基金Supported by Major Program for New Transgenic Plant VarietiesBreeding (2008ZX08012-04)~~
文摘[Objective] The research aimed to assess the effect of transgenic Bt plus CpTI cotton variety SGK321 on carboxylesterase and acetylcholinesterase of cotton aphid Aphis gossypii and provide theoretical basis for studying the biosafety of transgenic cotton.[Method] Cotton aphids were fed with SGK321 and Shiyuan321（normal parental varieties） for over 40 generations.Enzyme activities were compared between cotton aphids feeding on SGK321 for 1,2,3,41,42 and 43 generations with those on Shiyuan321.[Result] The carboxylesterase activity of cotton aphids feeding on SGK321 for 1 generation was significantly higher than those feeding on Shiyuan321.Acetylcholinesterase activity of cotton aphids feeding on SGK321 for 1,2 and 3 generations were significantly higher than those feeding on Shiyuan321 in the same generation.But there was no significant difference of enzyme activity between cotton aphids feeding on SGK321 for a long term and those feeding on parental cotton.[Conclusion] The cotton aphid that feeding on transgenic Bt plus CpTI cotton SGK321 for a long time has adaptivity to SGK321 by regulating the detoxifying enzyme.
基金the National Natural Science Foundation of China （30470219）.
文摘Carboxylesterases （CarEs） from two field populations of the oriental migratory locust, Locusta migratoria manilensis （Meyen）, were examined to try to understand their contribution to malathion insensitivity. The CarEs activities in Wudi population （WD） were 1.75- and 1.50-fold significantly higher than those in Huangliu population （HL） when a-naphthyl acetate （a-NA） and [3-naphthyl acetate were used as substrates, respectively. Such elevated CarEs activities presented in the WD could be because of an increased staining intensity of the a-NA-hydrolyzing CarEs as shown on the nondenaturing polyacrylamide gel electrophoresis. Inhibition studies of CarEs using paraoxon and malaoxon indicated that CarE activities in the HL were more strongly inhibited than those in the WD. Furthermore, a 449-bp DNA fragment of CarE was obtained from L. migratoria manilensis. Hemiquantity reverse transcription-polymerase chain reaction analysis showed that CarE gene expression level in the WD was higher than that in the HL. The higher CarE activities and the increased CarE mRNA level in the WD appeared to be associated with decreased susceptibility to malathion in the WD due to the application of organophosphorus insecticides.
基金funded by grants from the National Science & Technology Major Project of China ‘Key New Drug Creation and Manufacturing Program’ (2017ZX09301012-006)the National Natural Science Foundation of China (81603380)the Strategic Priority Research Program of the Chinese Academy of Sciences (XDA12050306)
文摘Methyl(S)-4-(6-amino-9 H-purin-9-yl)-2-hydroxybutanoate(DZ2002) is a potent reversible inhibitor of S-adenosyl-L-homocysteine hydrolase(SAHH). Due to its ester structure, DZ2002 is rapidly hydrolyzed in rat blood to 4-(6-amino-9 H-purin-9-yl)-2-hydroxybutyric acid(DZA) during and after blood sampling from rats; this hampers accurate determination of the circulating DZ2002 and its acid metabolite DZA in rats. To this end, a method for determining the blood concentrations of DZ2002 and DZA in rats was developed by using methanol to immediately deactivate blood carboxylesterases during sampling. The newly developed bioanalytical assay possessed favorable accuracy and precision with lower limit of quantification of 31 nM for DZ2002 and DZA. This validated assay was applied to a rat pharmacokinetic study of DZ2002. After oral administration, DZ2002 was found to be extensively converted into DZA. The level of systemic exposure to DZ2002 was significantly lower than that of DZA. The apparent oral bioavailability of DZ2002 was 90%–159%. The mean terminal half-lives of DZ2002 and DZA were 0.3–0.9 and 1.3–5.1 h, respectively. The sample preparation method illustrated here may be adopted for determination of other circulating ester drugs and their acid metabolites in rodents.
基金supported by a grant from the Natural Science Foundation of Hubei Province of China(No.2011CD-B550)
文摘Carboxylesterases (CESs) play important roles in the metabolism of endogenous and foreign compounds in physiological and pharmacological responses. The aim of this study was to investigate the effect of dexamethasone at different doses on the expression of CES1 and CES2. Imidapril and irinotecan hydrochloride (CPT-11) were used as special substrates for CES1 and CES2, respectively. Rat hepatocytes were cultured and treated with different concentrations of dexamethasone. The hydrolytic activity of CES1 and CES2 was tested by incubation experiment and their expression was quantitated by real-time PCR. A pharmacokinetic study was conducted in SD rats to further evaluate the effect of dexamethasone on CESs activity in vivo. Western blotting was performed to investigate the regulatory mechanism related to pregnane X receptor (PXR) and glucocorticoid receptor (GR). The results showed that exposure of cultured rat hepatocytes to nanomolar dexamethasone inhibited the imidapril hydrolase activity, which was slightly elevated by micromolar dexamethasone. For CES2, CPT-11 hydrolase activity was induced only when dexamethasone reached micromolar levels. The real-time PCR demonstrated that CES1 mRNA was markedly decreased by nanomolar dexamethasone and increased by micromolar dexamethasone, whereas CES2 mRNA was significantly increased by micromolar dexamethasone. The results of a complementary animal study showed that the concurrent administration of dexamethasone significantly increased the plasma concentration of the metabolite of imidapril while the ratio of CPT-11 to its metabolite SN-38 was significantly decreased. PXR protein was gradually increased by serial concentrations of dexamethasone. However, only nanomolar dexamethasone elevated the level of GR protein. The different concentrations of dexamethasone required suggested that suppression of CES1 may be mediated by GR whereas the induction of CES2 may result from the role of PXR. It was concluded that dexamethasone at different concentrations can differentially regulate CES1 and CES2.
基金supported by National Institutes of Health Grants R01 EB018748,R21 Al153031University of Cincinnati Cancer Center(Yan,B).
文摘Infectious pandemics result in hundreds and millions of deaths,notable examples of the Spanish Flu,the Black Death and smallpox.The current pandemic,caused by SARS-CoV-2(severe acute respiratory syndrome coronavirus 2),is unprecedented even in the historical term of pandemics.The unprecedentedness is featured by multiple surges,rapid identification of therapeutic options and accelerated development of vaccines.Remdesivir,originally developed for Ebola viral disease,is the first treatment of COVID-19(Coronavirus disease 2019)approved by the United States Food and Drug Administration.As demonstrated by in vitro and preclinical studies,this therapeutic agent is highly potent with a broad spectrum activity against viruses from as many as seven families even cross species.However,randomized controlled trials have failed to confirm the efficacy and safety.Remdesivir improves some clinical signs but not critical parameters such as mortality.This antiviral agent is an ester/phosphorylation prodrug and excessive hydrolysis which increases cellular toxicity.Remdesivir is given intravenously,leading to concentration spikes and likely increasing the potential of hydrolysis-based toxicity.This review has proposed a conceptual framework for improving its efficacy and minimizing toxicity not only for the COVID-19 pandemic but also for future ones caused by remdesivir-sensitive viruses.
文摘The melon aphid, Aphis gossypii Glover (Hemiptera: Aphididae), is a highly polyphagous sap sucking pest on wide varieties of crops including cotton and vegetables. It is a notorious vector of many plant viruses that are persistently and non-persistently transmitted. In nature, aphids are regulated by their natural enemies. However, chemical control remains a major management tool even though resistance to insecticides has been documented worldwide. A better understanding of mechanisms by which insecticide resistance occurs and its early detection is desirable to develop effective management strategies. The present investigation was conducted to study the development of resistance to an organophosphate (OP) compound-dimethoate, identify biochemical mechanism(s) involved in resistance and study cross-resistance to imidacloprid in laboratory selected A. gossypii strains in comparison to susceptible strains. Bioassay studies revealed that the LC50 values increased dramatically with dimethoate selection in resistant strains and the resistance ratio (RR) was 270-, 243- and 210-fold greater than that of the susceptible strains by 30th generation. Further, biochemical assays revealed enhanced activities of carboxylesterases (CarE), glutathione S-transferases (GSTs) and cytochrome P450-mediated p-Nitroanisole O-demethylase (PNOD) in resistant strains supporting their role in dimethoate detoxification. This study thus revealed that enhanced activity of detoxifying enzymes viz., CarE, GSTs and PNODs is one of the mechanisms underlying dimethoate resistance in A. gossypii collected from South India. Interestingly, the possibility of negatively correlated cross-resistance to imidacloprid was identified in three OP- resistant strains exhibiting 2.97-, 2.56- and 3.76-fold sensitivity to imidacloprid (a novel neonicotinoid). This indicated that the latter was less affected by the resistance mechanism(s) present.
文摘The melon aphid, <i>Aphis gossypii</i> Glover (Hemiptera: Aphididae), is a highly polyphagous sap sucking pest on wide varieties of crops including cotton and vegetables. It is a notorious vector of many plant viruses that are persistently and non-persistently transmitted. In nature, aphids are regulated by their natural enemies. However, chemical control remains a major management tool even though resistance to insecticides has been documented worldwide. A better understanding of mechanisms by which insecticide resistance occurs and its early detection is desirable to develop effective management strategies. The present investigation was conducted to study the development of resistance to an organophosphate (OP) compound-dimethoate, identify biochemical mechanism(s) involved in resistance and study cross-resistance to imidacloprid in laboratory selected <i>A. gossypii</i> strains in comparison to susceptible strains. Bioassay studies revealed that the LC50 values increased dramatically with dimethoate selection in resistant strains and the resistance ratio (RR) was 270-, 243- and 210-fold greater than that of the susceptible strains by 30th generation. Further, biochemical assays revealed enhanced activities of carboxylesterases (CarE), glutathione S-transferases (GSTs) and cytochrome P450-mediated <i>p</i>-Nitroanisole <i>O</i>-demethylase (PNOD) in resistant strains supporting their role in dimethoate detoxification. This study thus revealed that enhanced activity of detoxifying enzymes <i>viz</i>., CarE, GSTs and PNODs is one of the mechanisms underlying dimethoate resistance in <i>A. gossypii</i> collected from South India. Interestingly, the possibility of negatively correlated cross-resistance to imidacloprid was identified in three OP- resistant strains exhibiting 2.97-, 2.56- and 3.76-fold sensitivity to imidacloprid (a novel neonicotinoid). This indicated that the latter was less affected by the resistance mechanism(s) present.
基金supported by the Key Projects in the National Science & Technology Pillar Program of China (2011BAK10B07)the National Major Special Projects in the Ministry of Science and Technology of China (2012 2X09301003-001-010)
文摘Background: T-2 toxin poses a great threat to human health because it has the highest toxicity of the currently known trichothecene mycotoxins. To understand the in vivo toxicity and transformation mechanism of T-2 toxin, we investigated the role of two principal phase Ⅰ drug-metabolizing enzymes(cytochrome P450 [CYP450] enzymes) on the metabolism of T-2 toxin, which are crucial to the metabolism of endogenous substances and xenobiotics. We also investigated carboxylesterase, which also plays an important role in the metabolism of toxic substances.Methods: A chemical inhibition method and a recombinant method were employed to investigate the metabolism of the T-2 toxin by the CYP450 enzymes, and a chemical inhibition method was used to study carboxylesterase metabolism. Samples incubated with human liver microsomes were analyzed by high performance liquid chromatography-triple quadrupole mass spectrometry(HPLC- Qq Q MS) after a simple pretreatment.Results: In the presence of a carboxylesterase inhibitor, only 20% T-2 toxin was metabolized. When CYP enzyme inhibitors and a carboxylesterase inhibitor were both present, only 3% of the T-2 toxin was metabolized. The contributions of the CYP450 enzyme family to T-2 toxin metabolism followed the descending order CYP3A4, CYP2E1, CYP1A2, CYP2B6 or CYP2D6 or CYP2C19.Conclusions: Carboxylesterase and CYP450 enzymes are of great importance in T-2 toxin metabolism, in which carboxylesterase is predominant and CYP450 has a subordinate role. CYP3A4 is the principal member of the CYP450 enzyme family responsible for T-2 toxin metabolism. The metabolite produced by carboxylesterase is HT-2, and the metabolite produced by CYP 3A4 is 3'-OH T-2. The different metabolites show different toxicities. Our results will provide useful data concerning the toxic mechanism, the safety evaluation, and the health risk assessment of T-2 toxin.
文摘Despite the fact that the phenomenon of capacitation was discovered over half century ago and much progress has been made in identifying sperm events involved in capacitation, few specific molecules of epididymal origin have been identified as being directly involved in this process in vivo. Previously, our group cloned and characterized a carboxyl esterase gene CesSa in the rat epididymis. The CES5A protein is mainly expressed in the corpus and cauda epididymidis and secreted into the corresponding lumens. Here, we report the function of CESSA in sperm maturation. By local injection of Lentivirus-mediated siRNA in the CESSA.expressing region of the rat epididymis, CesSa-knockdown animal models were created. These animals exhibited an inhibited sperm capacitation and a reduction in male fertility. These results suggest that CESSA plays an important role in sperm maturation and male fertility.
基金supported by the National Natural Science Foundation of China(Nos. 21572029, 31600641,81703604, 81773687, 81672961 and 81573501)the National Key Research and Development Program of China (Nos. 2017YFC1700200 and 2017YFC1702000)+2 种基金Program of Shanghai Academic/Technology Research Leader(No. 18XD1403600)Shuguang Program (No. 18SG40)supported by Shanghai Education Development Foundation and Shanghai Municipal Education Commission and the Innovative Entrepreneurship Program of High-level Talents in Dalian (Nos. 2016RQ025 and 2017RQ121)
文摘Carboxylesterase 1(CES1), one of the most abundant serine hydrolases in mammals, has drawn much attentions in recent years, owing to this enzyme involves in many physiological processes via hydrolysis of both endogenous esters and xenobiotic esters. Herein, to real-time monitor the activities of CES1 in various biological systems, a practical and iso form-specific fluorescent probe was developed on the basis of the substrate preference of CES1, as well as the structural and optical properties of BODIPY dyes. After screening of a panel of BODIPY ester derivatives, probe 1 displayed the best combination of specificity,sensitivity, enzymatic kinetics and applicability for monitoring CES1 activities in real samples. This probe was successfully used to detect CESl activities in several biological systems including tissue preparations,living cells, tissue slices and zebrafish. Furthermore, the biomedical applications of probe 1 for screening of CES1 inhibitors were also demonstrated using tissue preparations or living cells as enzyme sources. In summary, a practical and broadly applicable tool for real-time monitoring CES1 in biological systems was developed and well-characterized, which held great promise for further investigations on CES1-associated drug discovery, clinical practice and fundamental research.
基金supported by the National Natural Science Foundation of China (31371956, 31572023 and 31772186)
文摘Carboxylesterase(CarE)was considered as important phase-I detoxifying enzymes which participated in detoxification of different types of insecticides.Up-regulation of CarE genes has been proved playing a major role in insecticide resistance in many pest insects,but its involvement in resistance to insecticides in Plutella xylostella has been rarely reported.In this study,a CarE cDNA named PxαE8 was identified in P.xylostella,which has an open reading frame of 1599 nucleotides and putatively encodes 532 amino acids.The investigation of spatial expression profiles of PxαE8 revealed that it was expressed in all developmental stages,especially in larvae and adults.The body part/tissue-specific expression profiles showed that the PxαE8 mainly expressed in fat body,malpighian tubule and hemolymph of larvae.Further,the relative expression of PxαE8 in two multi-resistant field populations,Hainan(HN)and Guangdong(GD)populations,was found 24.4-and 15.5-fold higher than that in susceptible population,respectively.Knockdown of PxαE8 by RNA interference dramatically increased the mortalities of larvae of HN population treated with LC_(50) of beta-cypermethrin and phoxim by 25.3 and 18.3%,respectively.These results suggested that up-regulation of PxαE8 was involved in resistance to both beta-cypermethrin and phoxim in P.xylostella,which shed light on further understanding of molecular mechanisms of multi-insecticide-resistance in P.xylostella and other pest insects.
