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1.
J Enzyme Inhib Med Chem ; 37(1): 629-640, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35100926

RESUMO

Pancreatic lipase (PL) is a well-known key target for the prevention and treatment of obesity. Human carboxylesterase 1A (hCES1A) has become an important target for the treatment of hyperlipidaemia. Thus, the discovery of potent dual-target inhibitors based on PL and hCES1A hold great potential for the development of remedies for treating related metabolic diseases. In this study, a series of natural triterpenoids were collected and the inhibitory effects of these triterpenoids on PL and hCES1A were determined using fluorescence-based biochemical assays. It was found that oleanolic acid (OA) and ursolic acid (UA) have the excellent inhibitory effects against PL and hCES1A, and highly selectivity over hCES2A. Subsequently, a number of compounds based on the OA and UA skeletons were synthesised and evaluated. Structure-activity relationship (SAR) analysis of these compounds revealed that the acetyl group at the C-3 site of UA (compound 41) was very essential for both PL and hCES1A inhibition, with IC50 of 0.75 µM and 0.014 µM, respectively. In addition, compound 39 with 2-enol and 3-ketal moiety of OA also has strong inhibitory effects against both PL and hCES1A, with IC50 of 2.13 µM and 0.055 µM, respectively. Furthermore, compound 39 and 41 exhibited good selectivity over other human serine hydrolases including hCES2A, butyrylcholinesterase (BChE) and dipeptidyl peptidase IV (DPP-IV). Inhibitory kinetics and molecular docking studies demonstrated that both compounds 39 and 41 were effective mixed inhibitors of PL, while competitive inhibitors of hCES1A. Further investigations demonstrated that both compounds 39 and 41 could inhibit adipocyte adipogenesis induced by mouse preadipocytes. Collectively, we found two triterpenoid derivatives with strong inhibitory ability on both PL and hCES1A, which can be served as promising lead compounds for the development of more potent dual-target inhibitors targeting on PL and hCES1A.


Assuntos
Hidrolases de Éster Carboxílico/antagonistas & inibidores , Descoberta de Drogas , Inibidores Enzimáticos/farmacologia , Lipase/antagonistas & inibidores , Pâncreas/enzimologia , Triterpenos/farmacologia , Hidrolases de Éster Carboxílico/metabolismo , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Humanos , Lipase/metabolismo , Estrutura Molecular , Relação Estrutura-Atividade , Triterpenos/síntese química , Triterpenos/química
2.
Acta Pharmacol Sin ; 43(4): 1072-1081, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34183756

RESUMO

Jingyin granules, a marketed antiviral herbal medicine, have been recommended for treating H1N1 influenza A virus infection and Coronavirus disease 2019 (COVID-19) in China. To fight viral diseases in a more efficient way, Jingyin granules are frequently co-administered in clinical settings with a variety of therapeutic agents, including antiviral drugs, anti-inflammatory drugs, and other Western medicines. However, it is unclear whether Jingyin granules modulate the pharmacokinetics of Western drugs or trigger clinically significant herb-drug interactions. This study aims to assess the inhibitory potency of the herbal extract of Jingyin granules (HEJG) against human drug-metabolizing enzymes and to clarify whether HEJG can modulate the pharmacokinetic profiles of Western drug(s) in vivo. The results clearly demonstrated that HEJG dose-dependently inhibited human CES1A, CES2A, CYPs1A, 2A6, 2C8, 2C9, 2D6, and 2E1; this herbal medicine also time- and NADPH-dependently inhibited human CYP2C19 and CYP3A. In vivo tests showed that HEJG significantly increased the plasma exposure of lopinavir (a CYP3A-substrate drug) by 2.43-fold and strongly prolonged its half-life by 1.91-fold when HEJG (3 g/kg) was co-administered with lopinavir to rats. Further investigation revealed licochalcone A, licochalcone B, licochalcone C and echinatin in Radix Glycyrrhizae, as well as quercetin and kaempferol in Folium Llicis Purpureae, to be time-dependent CYP3A inhibitors. Collectively, our findings reveal that HEJG modulates the pharmacokinetics of CYP substrate-drug(s) by inactivating CYP3A, providing key information for both clinicians and patients to use herb-drug combinations for antiviral therapy in a scientific and reasonable way.


Assuntos
COVID-19 , Vírus da Influenza A Subtipo H1N1 , Animais , Antivirais/farmacologia , COVID-19/tratamento farmacológico , Inibidores do Citocromo P-450 CYP3A , Interações Ervas-Drogas , Humanos , Microssomos Hepáticos , Ratos
3.
Mater Sci Eng C Mater Biol Appl ; 130: 112472, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34702509

RESUMO

Cancer-derived exosomes or their specific components hold great promise for early diagnosis and precise staging of cancers. This work aimed to construct a novel enzyme-activatable fluorescent substrate for real-time detection and in situ imaging of a key exosomal surface protein CD26 in various biological systems, as well as to reveal the relevance of exosomal CD26 to the tumorigenesis. For these purposes, a group of Gly-Pro amides deriving from several near-infrared fluorophores were designed on the basis of the unique prolyl-cleaving dipeptidease activity of CD26, while molecular docking simulations were applied to assess the possibility of the designed amides as CD26 specific substrates. Following virtual screening and experimental validation, it was observed that GP-ACM displayed the best combination of high sensitivity and excellent specificity to CD26. The sensing and imaging ability of GP-ACM towards CD26 were examined in a range of biological systems, such as living cells, in situ tissues, and the exosomes secreted from cancer cells. Under physiological conditions, GP-ACM can be readily hydrolyzed by CD26 to release the fluorescent product ACM. The fluorescent product emits strong near-infrared fluorescence signals around 660 nm, which can be easily captured by the devices equipped with a fluorescence detector. GP-ACM prolyl-cleaving reaction shows excellent specificity and rapid response towards CD26, while its fluorescent product ACM displays good chemical stability and outstanding photostability. With the help of GP-ACM, CD26 in living cells, tissues and the tumor-secreted exosomes can be real-time monitored and in-situ imaged, while further investigations reveal that the exosomal CD26 activities are abnormally elevated with the progression of colon tumor. Collectively, the present study offers a practical optical assay for real-time monitoring CD26 activities in multiple complex biological systems including the exosomes secreted by tumor cells. The simplicity and effectiveness of this assay hold great potential for facilitating fundamental researches and clinical diagnosis of exosomal CD26 associated diseases.


Assuntos
Neoplasias Colorretais , Exossomos , Neoplasias Colorretais/diagnóstico por imagem , Dipeptidil Peptidase 4 , Corantes Fluorescentes , Humanos , Simulação de Acoplamento Molecular
4.
Curr Med Chem ; 2021 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-34525910

RESUMO

Prolyl-specific peptidases or proteases, including Dipeptidyl Peptidase 2, 4, 6, 8, 9, 10, Fibroblast Activation Protein, prolyl endopeptidase and prolyl carboxypeptidase, belong to the dipeptidyl peptidase family. In human physiology and anatomy, they have homology amino acid sequences, similarities in structure, but play distinct functions and roles. Some of them also play important roles in the metabolism of drugs containing endogenous peptides, xenobiotics containing peptides, and exogenous peptides. The major functions of these peptidases in both the metabolism of human health and bioactive peptides are of significant importance in the development of effective inhibitors to control the metabolism of endogenous bioactive peptides. The structural characteristics, distribution of tissue, endogenous substrates, and biological functions were summarized in this review. Furthermore, the xenobiotics metabolism of the dipeptidyl peptidase family is illustrated. All the evidence and information summarized in this review would be very useful for researchers to extend the understanding of the proteins of these families and offer advice and assistance in physiology and pathology studies.

5.
Chem Biol Interact ; 345: 109566, 2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34174250

RESUMO

Mammalian carboxylesterases (CES), the key members of the serine hydrolase superfamily, hydrolyze a wide range of endogenous substances and xenobiotics bearing ester or amide bond(s). In humans, most of identified CES are segregated into the CES1A and CES2A subfamilies. Strong inhibition on human CES (including hCES1A and hCES2A) may modulate pharmacokinetic profiles of CES-substrate drugs, thereby changing the pharmacological and toxicological responses of these drugs. This review covered recent advances in discovery of hCES inhibitors from clinically available medications, as well as their impact on CES-associated drug metabolism. Three comprehensive lists of hCES inhibitors deriving from clinically available medications including therapeutic drugs, pharmaceutical excipients and herbal medicines, alongside with their inhibition potentials and inhibition parameters, are summarized. Furthermore, the potential risks of hCES inhibitors to trigger drug/herb-drug interactions (DDIs/HDIs) and future concerns in this field are highlighted. Potent hCES inhibitors may trigger clinically relevant DDIs/HDIs, especially when these inhibitors are co-administrated with CES substrate-drugs with very narrow therapeutic windows. All data and knowledge presented here provide key information for the clinicians to assess the risks of clinically available hCES inhibitors on drug metabolism. In future, more practical and highly specific substrates for hCES1A/hCES2A should be developed and used for studies on CES-mediated DDIs/HDIs both in vitro and in vivo.


Assuntos
Carboxilesterase/antagonistas & inibidores , Carboxilesterase/metabolismo , Inibidores Enzimáticos/farmacologia , Preparações Farmacêuticas/metabolismo , Animais , Descoberta de Drogas , Humanos , Inativação Metabólica/efeitos dos fármacos
6.
Anal Methods ; 13(24): 2671-2678, 2021 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-34036983

RESUMO

Dipeptidyl peptidase-IV (DPP-IV) plays a critical role in glucose metabolism and has become an important target for type 2 diabetes mellitus. We previously reported a two-photon fluorescent probe glycyl-prolyl-N-butyl-4-amino-1,8-naphthalimide (GP-BAN) for DPP-IV detection with high specificity and sensitivity. In this study, a high-throughput screening (HTS) method for DPP-IV inhibitors using human plasma as the enzyme source was established and optimized. Further investigations demonstrate that the IC50 value of sitagliptin (listed as the DPP-IV inhibitor) determined with human recombinant DPP-IV (36.22 nM) is very similar to that in human plasma (39.18 nM), and sitagliptin acts as a competitive inhibitor against human plasma DPP-IV-mediated GP-BAN hydrolysis. These results indicate that expensive human recombinant DPP-IV can be replaced by human plasma in this GP-BAN-based assay. On this basis, GP-AMC (commercial probe) was used as a comparison to verify this method, and the catalytic efficacy (Vmax/Km) for GP-AMC (0.09 min-1) hydrolysis in human plasma is lower than that for GP-BAN (0.21 min-1). Further analysis of inhibition kinetics (sitagliptin) and molecular docking (GP-BAN and GP-AMC) showed that GP-BAN has better specificity and affinity for enzymes than GP-AMC. Finally, the optimized method was used for the HTS of DPP-IV inhibitors in 69 natural alkaloids.


Assuntos
Diabetes Mellitus Tipo 2 , Inibidores da Dipeptidil Peptidase IV , Diabetes Mellitus Tipo 2/tratamento farmacológico , Ensaios de Triagem em Larga Escala , Humanos , Simulação de Acoplamento Molecular , Fosfato de Sitagliptina
7.
J Enzyme Inhib Med Chem ; 36(1): 1079-1087, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34030574

RESUMO

Inhibitors of COMT are clinically used for the treatment of Parkinson's disease. Here, we report the first natural pentacyclic triterpenoid-type COMT inhibitors and their structure-activity relationships and inhibition mechanism. The most potent compounds were found to be oleanic acid, betulinic acid and celastrol with IC50 values of 3.89-5.07 µM, that acted as mixed (uncompetitive plus non-competitive) inhibitors of COMT, representing a new skeleton of COMT inhibitor. Molecular docking suggested that they can specifically recognise and bind with the unique hydrophobic residues surrounding the catechol pocket. Furthermore, oleanic acid and betulinic acid proved to be less disruptive of mitochondrial membrane potential (MMP) compared to tolcapone, thus reducing the risk of liver toxicity. These findings could be used to produce an ideal lead compound and to guide synthetic efforts in generating related derivatives for further preclinical testing.


Assuntos
Produtos Biológicos/farmacologia , Catecol O-Metiltransferase/metabolismo , Inibidores Enzimáticos/farmacologia , Triterpenos Pentacíclicos/farmacologia , Produtos Biológicos/síntese química , Produtos Biológicos/química , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Humanos , Cinética , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Conformação Molecular , Simulação de Acoplamento Molecular , Triterpenos Pentacíclicos/síntese química , Triterpenos Pentacíclicos/química , Proteínas Recombinantes/metabolismo , Estereoisomerismo , Relação Estrutura-Atividade
8.
Bioorg Med Chem ; 40: 116187, 2021 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-33965840

RESUMO

Carboxylesterase 2 (CES2) is one of the most important Phase I drug metabolizing enzymes in the carboxylesterase family. It plays crucial roles in the bioavailability of oral ester prodrugs and the therapeutic effect of some anticancer drugs such as irinotecan (CPT11) and capecitabine. In addition to the well-known roles of CES2 in xenobiotic metabolism, the enzyme also participates in endogenous metabolism and the production of lipids. In this study, we synthesized a series of pyrazolones and assayed their inhibitory effects against CES2 in vitro. Structure-activity relationship analysis of these pyrazolones reveals that the introduction of 4-methylphenyl unit (R1), 4-methylbenzyl (R2) and cyclohexyl (R3) moieties are beneficial for CES2 inhibition. Guided by these SARs results, 1-cyclohexyl-4-(4-methylbenzyl)-3-p-tolyl-1H- pyrazol-5(4H)-one (27) was designed and synthesized. Further investigations demonstrated that the compound 27 exhibited stronger CES2 inhibition activity with a lower IC50 value (0.13 µM). The inhibition kinetic study demonstrated that compound 27 inhibited the hydrolysis of CES2-fluorescein diacetate (FD) through non-competitive inhibition. In addition, the molecular docking showed that the core of pyrazolone, the cyclohexane moiety, 4-methylbenzyl and 4-methylphenyl groups in compound 27 all played important roles with the amino acid residues of CSE2. Also, compound 27 could inhibit adipocyte adipogenesis induced by mouse preadipocytes. In brief, we designed and synthesized a novel pyrazolone compound with a strong inhibitory ability on CES2 and could inhibit the adipogenesis induced by mouse preadipocytes, which can be served as a promising lead compound for the development of more potent pyrazolone-type CES2 inhibitors, and also used as a potential tool for exploring the biological functions of CES2 in human being.


Assuntos
Adipogenia/efeitos dos fármacos , Carboxilesterase/antagonistas & inibidores , Descoberta de Drogas , Inibidores Enzimáticos/farmacologia , Pirazolonas/farmacologia , Carboxilesterase/metabolismo , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Humanos , Simulação de Acoplamento Molecular , Estrutura Molecular , Pirazolonas/síntese química , Pirazolonas/química , Relação Estrutura-Atividade , Células Tumorais Cultivadas
9.
ChemMedChem ; 16(10): 1600-1604, 2021 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-33527731

RESUMO

Pancreatic lipase (PL), a key target for the prevention and treatment of obesity, plays crucial roles in the hydrolysis and absorption of in dietary fat. In this study, a series of pyrazolones was synthesized, and their inhibitory effects against PL were assayed by using 4-methylumbelliferyl oleate (4-MUO) as optical substrate for PL. Comprehensive structure-activity relationship analysis of these pyrazolones led us to design and synthesize a novel compound P32 (5-(naphthalen-2-yl)-2-phenyl-4-(thiophen-2-ylmethyl)-2,4-dihydro-3H-pyrazol-3-one) as a potent mixed-competitive inhibitor of PL (IC50 =0.30 µM). In addition, P32 displayed some selectivity over other known serine hydrolases. A molecular docking study for P32 demonstrated that the inhibitory activity of P32 towards PL could be attributed to the π-π interactions of 2-naphthyl unit (R1 ) and hydrophobic interactions of phenyl moiety (R3 ) with the active site of PL. Thus, P32 could serve as promising lead compound for the development of more efficacious and selective pyrazolones-type PL inhibitors for biomedical applications.


Assuntos
Desenho de Fármacos , Inibidores Enzimáticos/farmacologia , Lipase/antagonistas & inibidores , Pirazolonas/farmacologia , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Humanos , Lipase/metabolismo , Modelos Moleculares , Estrutura Molecular , Pâncreas/enzimologia , Pirazolonas/síntese química , Pirazolonas/química , Relação Estrutura-Atividade
10.
Eur J Med Chem ; 209: 112856, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33007602

RESUMO

Human carboxylesterase 2 (hCES2A), one of the major serine hydrolases distributed in the small intestine, plays a crucial role in hydrolysis of ester-bearing drugs. Accumulating evidence has indicated that hCES2A inhibitor therapy can modulate the pharmacokinetic and toxicological profiles of some important hCES2A-substrate drugs, such as the anticancer agent CPT-11. Herein, a series of indanone-chalcone hybrids are designed and synthesized to find potent and highly selective hCES2A inhibitors. Inhibition assays demonstrated that most indanone-chalcone hybrids displayed strong to moderate hCES2A inhibition activities. Structure-hCES2A inhibition activity relationship studies showed that introduction of a hydroxyl at the C4' site and introduction of an N-alkyl group at the C6 site were beneficial for hCES2A inhibition. Particularly, B7 (an N-alkylated 1-indanone-chalcone hybrid) exhibited the most potent inhibition on hCES2A and excellent specificity (this agent could not inhibit other human esterases including hCES1A and butyrylcholinesterase). Inhibition kinetic analyses demonstrated that B7 potently inhibited hCES2A-mediated FD hydrolysis in a mixed inhibition manner, with a calculated Ki value of 0.068 µM. Furthermore, B7 was capable of inhibiting intracellular hCES2A in living cells and displayed good metabolic stability. Collectively, our findings show that indanone-chalcone hybrids are good choices for the development of hCES2A inhibitors, while B7 is a promising candidate for the development of novel anti-diarrhea agents to ameliorate irinotecan-induced intestinal toxicity.


Assuntos
Carboxilesterase/antagonistas & inibidores , Chalconas/química , Chalconas/farmacologia , Indanos/química , Indanos/farmacologia , Carboxilesterase/metabolismo , Chalconas/síntese química , Desenho de Fármacos , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Células Hep G2 , Humanos , Indanos/síntese química , Simulação de Acoplamento Molecular , Relação Estrutura-Atividade
11.
Bioorg Chem ; 105: 104367, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33080495

RESUMO

Human Carboxylesterase 2A (hCES2A), one of the most important serine hydrolases, plays crucial roles in the hydrolysis and the metabolic activation of a wide range of esters and amides. Increasing evidence has indicated that potent inhibition on intestinal hCES2A may reduce the excessive accumulation of SN-38 (the hydrolytic metabolite of irinotecan with potent cytotoxicity) in the intestinal tract and thereby alleviate the intestinal toxicity triggered by irinotecan. In this study, more than sixty natural alkaloids have been collected and their inhibitory effects against hCES2A are assayed using a fluorescence-based biochemical assay. Following preliminary screening, seventeen alkaloids are found with strong to moderate hCES2A inhibition activity. Primary structure-activity relationships (SAR) analysis of natural isoquinoline alkaloids reveal that the benzo-1,3-dioxole group and the aromatic pyridine structure are beneficial for hCES2A inhibition. Further investigations demonstrate that a steroidal alkaloid reserpine exhibits strong hCES2A inhibition activity (IC50 = 0.94 µM) and high selectivity over other human serine hydrolases including hCES1A, dipeptidyl peptidase IV (DPP-IV), butyrylcholinesterase (BChE) and thrombin. Inhibition kinetic analyses demonstrated that reserpine acts as a non-competitive inhibitor against hCES2A-mediated FD hydrolysis. Molecular docking simulations demonstrated that the potent inhibition of hCES2A by reserpine could partially be attributed to its strong σ-π and S-π interactions between reserpine and hCES2A. Collectively, our findings suggest that reserpine is a potent and highly selective inhibitor of hCES2A, which can be served as a promising lead compound for the development of more efficacious and selective alkaloids-type hCES2A inhibitors for biomedical applications.


Assuntos
Alcaloides/farmacologia , Produtos Biológicos/farmacologia , Carboxilesterase/antagonistas & inibidores , Descoberta de Drogas , Inibidores Enzimáticos/farmacologia , Alcaloides/síntese química , Alcaloides/química , Produtos Biológicos/síntese química , Produtos Biológicos/química , Carboxilesterase/metabolismo , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Humanos , Cinética , Simulação de Acoplamento Molecular , Estrutura Molecular , Relação Estrutura-Atividade
12.
ACS Sens ; 5(7): 1987-1995, 2020 07 24.
Artigo em Inglês | MEDLINE | ID: mdl-32529833

RESUMO

Discovery of novel liver injury indicators and development of practical assays to detect target indicator(s) would strongly facilitate the diagnosis of liver disorders. Herein, an alternative biomarker discovery strategy was applied to find suitable endoplasmic reticulum-resident protein(s) as serologic indicator(s) for hepatocyte injury via analysis of the human proteome database among plasma and various organs. Both database searching and preliminary experiments suggested that human carboxylesterase 1A (CES1A), one of the most abundant and hepatic-restricted proteins, could serve as a good serologic indicator for hepatocyte injury. Then, a highly selective and practical bioluminescent sensor was developed for real-time sensing of CES1A in various biological systems including plasma. With the help of this bioluminescent sensor, the release of hepatic CES1A into the extracellular medium or the circulation system could be directly monitored. Further investigations demonstrated that serum activity levels of CES1A were elevated dramatically in mice with liver injury or patients with liver diseases. Collectively, this study provided solid evidence to support that CES1A was a novel serological indicator for hepatocyte injury. Furthermore, the strategy used in this study paved a new way for the rational discovery of practical indicators to monitor the dynamic progression of injury in a given tissue or organ.


Assuntos
Carboxilesterase , Estresse do Retículo Endoplasmático , Retículo Endoplasmático , Hepatócitos , Animais , Humanos , Fígado , Camundongos
13.
Chem Biol Interact ; 315: 108871, 2020 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-31669218

RESUMO

Clopidogrel, a clinically used antiplatelet agent, can be readily hydrolyzed by human carboxylesterase 1A (CES1A) to release an inactive metabolite clopidogrel carboxylic acid (CCA). In this study, clopidogrel was used as a tool substrate to investigate the interspecies variation of clopidogrel hydrolysis in hepatic microsomes from various mammals including human and six laboratory animals (such as mouse, rat, rabbit, beagle dog, minipig and cynomolgus monkey). The results demonstrated that clopidogrel could be hydrolyzed into CCA by all tested hepatic microsomes from human or other mammals, but the hydrolytic rates greatly varied among species. Inhibition assays demonstrated that BNPP (an inactivator of mammalian CES) strongly inactivated clopidogrel hydrolytic activity in all tested hepatic microsomes, suggested that mammalian CES were major contributor(s) responsible for clopidogrel hydrolysis in hepatic preparations from all above-mentioned species. By contrast, the response of a reversible inhibitor of human CES1A on clopidogrel hydrolysis in these liver preparations varied significantly among different species. Moreover, the enzymatic kinetics and the apparent kinetic parameters of clopidogrel hydrolysis in hepatic microsomes from various animal species were evaluated and compared to each other. These findings provide crucial information for deeply understanding the differences in catalytic behaviors of mammalian CES, which will be very helpful for choosing suitable laboratory animal(s) for whole tests of CES1A substrate-drugs.


Assuntos
Clopidogrel/metabolismo , Mamíferos/metabolismo , Microssomos Hepáticos/metabolismo , Animais , Hidrolases de Éster Carboxílico/metabolismo , Cães , Humanos , Hidrólise , Cinética , Macaca fascicularis , Camundongos , Coelhos , Ratos , Suínos , Porco Miniatura
15.
Fitoterapia ; 137: 104199, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31175950

RESUMO

Human carboxylesterase 1 (CES1), primarily expressed in the liver and adipocytes, is responsible for the hydrolysis of endogenous esters (such as cholesteryl esters and triacylglycerols) and the metabolism of xenobiotic esters (such as clopidogrel and oseltamivir), thus participates in physiological and pathological processes. In this study, a series of natural pentacyclic triterpenoids were collected and their inhibitory effects against CES1 and CES2 were assayed using D-luciferin methyl ester (DME) and N-(2-butyl-1,3-dioxo-2,3-dihydro-1H-benzo[de] isoquinolin- 6-yl)- 2-chloroacetamide (NCEN) as specific optical substrate for CES1, and CES2, respectively. To this end, betulinic acid (BA) was found with strong inhibitory effect on CES1 (IC50, 15 nM) and relative high selectivity over CES2 (>2400-fold). Primary structure-activity relationships (SAR) analysis and docking simulations revealed that the carboxyl group at the C-28 site of BA is very essential for CES1 inhibition. The inhibition kinetic analyses demonstrated that BA was a potent competitive inhibitor against CES1-mediated DME hydrolysis. Further investigation on the inhibitory effect of BA in living cells (HepG2) based assays demonstrated that BA displayed potent inhibitory effects on intracellular CES1 activities, with the low IC50 value of 1.30 µM. These results demonstrated that BA is potent and highly selective CES1 inhibitor, which might be used as the promising tool for exploring the biological functions of CES1 in complex biological systems.


Assuntos
Hidrolases de Éster Carboxílico/antagonistas & inibidores , Triterpenos/farmacologia , Células Hep G2 , Humanos , Simulação de Acoplamento Molecular , Estrutura Molecular , Relação Estrutura-Atividade
16.
Front Pharmacol ; 10: 52, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30778299

RESUMO

Bufotalin (BFT), one of the naturally occurring bufodienolides, has multiple pharmacological and toxicological effects including antitumor activity and cardiotoxicity. This study aimed to character the metabolic pathway(s) of BFT and to identify the key drug metabolizing enzyme(s) responsible for hepatic metabolism of BFT in human, as well as to explore the related molecular mechanism of enzymatic selectivity. The major metabolite of BFT in human liver microsomes (HLMs) was fully identified as 5ß-hydroxylbufotalin by LC-MS/MS and NMR techniques. Reaction phenotyping and chemical inhibition assays showed that CYP3A4 and CYP3A5 were key enzymes responsible for BFT 5ß-hydroxylation. Kinetic analyses demonstrated that BFT 5ß-hydroxylation in both HLMs and human CYP3A4 followed the biphasic kinetics, while BFT 5ß-hydroxylation in CYP3A5 followed substrate inhibition kinetics. Furthermore, molecular docking simulations showed that BFT could bind on two different ligand-binding sites on both CYP3A4 and CYP3A5, which partially explained the different kinetic behaviors of BFT in CYP3A4 and CYP3A5. These findings are very helpful for elucidating the phase I metabolism of BFT in human and for deeper understanding the key interactions between CYP3A enzymes and bufadienolides, as well as for the development of bufadienolide-type drugs with improved pharmacokinetic and safety profiles.

17.
Chin Med ; 14: 56, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31889992

RESUMO

Background: Human carboxylesterases (hCES) are key serine hydrolases responsible for the hydrolysis of a wide range of endogenous and xenobiotic esters. Although it has been reported that some ginsenosides can modulate the activities of various enzymes, the inhibitory effects of ginsenosides on hCES have not been well-investigated. Methods: In this study, more than 20 ginsenosides were collected and their inhibitory effects on hCES1A and hCES2A were assayed using the highly specific fluorescent probe substrates for each isoenzyme. Molecular docking simulations were also performed to investigate the interactions between ginsenosides and hCES. Results: Among all tested ginsenosides, Dammarenediol II (DM) and 20S-O-ß-(d-glucosyl)-dammarenediol II (DMG) displayed potent inhibition against both hCES1A and hCES2A, while protopanaxadiol (PPD) and protopanaxatriol (PPT) exhibited strong inhibition on hCES2A and high selectivity over hCES1A. Introduction of O-glycosyl groups at the core skeleton decreased hCES inhibition activity, while the hydroxyl groups at different sites might also effect hCES inhibition. Inhibition kinetic analyses demonstrated that DM and DMG functioned as competitive inhibitors against hCES1A-mediated d-luciferin methyl ester (DME) hydrolysis. In contrast, DM, DMG, PPD and PPT inhibit hCES2A-mediated fluorescein diacetate (FD) hydrolysis via a mixed manner. Conclusion: The structure-inhibition relationships of ginsenosides as hCES inhibitors was investigated for the first time. Our results revealed that DM and DMG were potent inhibitors against both hCES1A and hCES2A, while PPD and PPT were selective and strong inhibitors against hCES2A.

18.
RSC Adv ; 9(68): 40168-40175, 2019 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-35541371

RESUMO

A mild strategy for visible-light-induced synthesis of bis(indolyl)methanes was developed using aromatic aldehydes and indole as substrates. This reaction could be performed at room temperature under catalyst- and additive-free conditions to synthesize a series of bis(indolyl)methanes in good to excellent yields. In addition, all synthesized bis(indolyl)methanes together with ß-substituted indole derivatives synthesized according to our previous work, were evaluated for their inhibitory effect against human carboxylesterase (CES1 and CES2). Primary structure-activity relationship analysis of all tested compounds showed that the modifications of ß-substituted indole at the ß-site with another indolyl group led to a significant enhancement of the inhibitory effect on CES2, and the bisindolyl structure is essential for CES2 inhibition. These results demonstrated that these bis(indolyl)methanes are potent and selective CES2 inhibitors, which might be helpful for medicinal chemists to design and develop more potent and selective CES2 inhibitors for biomedical applications.

19.
Int J Biol Macromol ; 120(Pt B): 1944-1954, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30268757

RESUMO

Human carboxylesterase 1 (hCE1) is a key enzyme responsible for the hydrolysis of a wide range of endogenous and xenobiotic esters, but the highly selective inhibitors against hCE1 are rarely reported. This study aimed to assess the inhibitory effects of natural flavonoids against hCE1 and to find potential specific hCE1 inhibitors. To this end, fifty-eight natural flavonoids were collected and their inhibitory effects against both hCE1 and hCE2 were assayed. Among all tested compounds, nevadensin, an abundant natural constitute from Lysionotus pauciflorus Maxim., displayed the best combination of inhibition potency and selectivity towards hCE1. The inhibition mechanism of nevadensin on hCE1 was further investigated using two site-specific hCE1 substrates including D-luciferin methyl ester (DME) and 2­(2­benzoyloxy­3­methoxyphenyl)benzothiazole (BMBT). Furthermore, docking simulations demonstrated that the binding area of nevadensin on hCE1 was highly overlapped with that of DME but was far away from that of BMBT, which was highly consistent with the inhibition modes of nevadensin. These findings found a natural occurring specific inhibitor of hCE1, which could be served as a lead compound for the development of novel hCE1 inhibitor with improved properties, and also hold great promise for investigating hCE1-ligand interactions.


Assuntos
Produtos Biológicos/farmacologia , Hidrolases de Éster Carboxílico/antagonistas & inibidores , Flavonas/farmacologia , Produtos Biológicos/metabolismo , Hidrolases de Éster Carboxílico/química , Hidrolases de Éster Carboxílico/metabolismo , Flavonas/metabolismo , Humanos , Concentração Inibidora 50 , Simulação de Acoplamento Molecular , Conformação Proteica , Especificidade por Substrato
20.
Bioorg Chem ; 77: 320-329, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29421708

RESUMO

Human carboxylesterases (hCEs) are key enzymes from the serine hydrolase superfamily. Among all identified hCEs, human carboxylesterase 2 (hCE2) plays crucial roles in the metabolic activation of ester drugs including irinotecan and flutamide. Selective and potent hCE2 inhibitors could be used to alleviate the toxicity induced by hCE2-substrate drugs. In this study, more than fifty flavonoids were collected to assay their inhibitory effects against hCE2 using a fluorescence-based method. The results demonstrated that C3 and C6 hydroxy groups were essential for hCE2 inhibition, while O-glycosylation or C-glycosylation would lead to the loss of hCE2 inhibition. Among all tested flavonoids, 5,6-dihydroxyflavone displayed the most potent inhibitory effect against hCE2 with the IC50 value of 3.50 µM. The inhibition mechanism of 5,6-dihydroxyflavone was further investigated by both experimental and docking simulations. All these findings are very helpful for the medicinal chemists to design and develop more potent and highly selective flavonoid-type hCE2 inhibitors.


Assuntos
Carboxilesterase/antagonistas & inibidores , Inibidores Enzimáticos/farmacologia , Flavonoides/farmacologia , Carboxilesterase/metabolismo , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Flavonoides/síntese química , Flavonoides/química , Humanos , Estrutura Molecular , Relação Estrutura-Atividade
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