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Chem Biol Interact ; : 108871, 2019 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-31669218


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.

Int J Biol Macromol ; 137: 261-269, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31260759


Human carboxylesterase 2 (CES2A), one of the most abundant hydrolases distributed in human small intestine and colon, play key roles in the hydrolysis of a wide range of prodrugs and other esters. Recent studies have demonstrated that CES2A inhibitors may ameliorate irinotecan-induced severe diarrhea, but the specific and efficacious inhibitors targeting intracellular CES2A are rarely reported. Herein, a large-scale screening campaign was conducted for discovery of potent and specific CES2A inhibitor(s). Following screening of more than one hundred of natural products, glabridin (a bioactive compound of Glycyrrhiza glabra L.) was found displaying potent inhibition on CES2A and high specificity over CES1A (>500-fold) and other serine hydrolases. Further investigation showed that glabridin was cell permeable and low cytotoxic, as well as capable of inhibiting intracellular CES2A in living cells, with the IC50 value of 0.52 µM. Molecular dynamics simulations showed that glabridin formed strong and stable interactions with both the catalytic cavity and Z site of CES2A via hydrophobic interactions. In summary, glabridin was a potent and specific inhibitor targeting intracellular CES2A, which could be used as an ideal lead compound to develop more efficacious CES2A inhibitors for modulating the pharmacokinetic behaviors of CES2A-substrate drugs and alleviating irinotecan-induced diarrhea.

Chem Biol Interact ; 308: 339-349, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31170387


Magnolol, the most abundant bioactive constituent of the Chinese herb Magnolia officinalis, has been found with multiple biological activities, including anti-oxidative, anti-inflammatory and enzyme-regulatory activities. In this study, the inhibitory effects and inhibition mechanism of magnolol on human carboxylesterases (hCEs), the key enzymes responsible for the hydrolytic metabolism of a variety of endogenous esters as well as ester-bearing drugs, have been well-investigated. The results demonstrate that magnolol strongly inhibits hCE1-mediated hydrolysis of various substrates, whereas the inhibition of hCE2 by magnolol is substrate-dependent, ranging from strong to moderate. Inhibition of intracellular hCE1 and hCE2 by magnolol was also investigated in living HepG2 cells, and the results showed that magnolol could strongly inhibit intracellular hCE1, while the inhibition of intracellular hCE2 was weak. Inhibition kinetic analyses and docking simulations revealed that magnolol inhibited both hCE1 and hCE2 in a mixed manner, which could be partially attributed to its binding at two distinct ligand-binding sites in each carboxylesterase, including the catalytic cavity and the regulatory domain. In addition, the potential risk of the metabolic interactions of magnolol via hCE1 inhibition was predicted on the basis of a series of available pharmacokinetic data and the inhibition constants. All these findings are very helpful in deciphering the metabolic interactions between magnolol and hCEs, and also very useful for avoiding deleterious interactions via inhibition of hCEs.

Compostos de Bifenilo/metabolismo , Hidrolases de Éster Carboxílico/metabolismo , Lignanas/metabolismo , Sítios de Ligação , Biocatálise , Compostos de Bifenilo/química , Hidrolases de Éster Carboxílico/antagonistas & inibidores , Domínio Catalítico , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/metabolismo , Células Hep G2 , Humanos , Hidrólise , Cinética , Lignanas/química , Simulação de Acoplamento Molecular
Zhonghua Zheng Xing Wai Ke Za Zhi ; 29(4): 268-72, 2013 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-24228508


OBJECTIVE: To investigate the possibility of placenta mesenchymal stem cells (PMSCs) differentiation into dermal fibroblast, and the potency of PMSCs used in cutaneous wound healing and stored as seed cells. METHODS: Enzyme digestion method was used to obtain PMSCs, and PMSCs were amplified after culture in vitro. Flow cytometry assay, osteogenic and adipogenic differentiation were done for MSCs identification. The induction medium composed of DMEM/F12 + 50 microg/ml VC + 100 ng/ml connective tissue growth factor (CTGF) was added into the 24-well plate for 16 days induction period. Pictures were taken to record morphologic change. Immunofluorescence tests were performed to detect Vimentin, FSP-1, collagen I , collagen III, desmin and laminin expression before and after induction. At the same time osteogenic and adipogenic differentiation were used to assay the differentiation ability change after induction. The induced dermal fibroblasts were frozen in liquid nitrogen and recovery and trypan blue was used to detect cell viability. RESULTS: After CTGF induction, PMSCs got obvious fibroblasts morphology, the protein level of Vimentin, FSP-1, collagen I, collagen III and Laminin increased, PMSCs started to express Desmin, the dermal fibroblasts specific proteins, and osteogenic and adipogenic differentiation ability was diminished. PMSCs were successfully induced into dermal fibroblasts, and these induced cells could get a high cell viability ( more than 90% ) after recovery. CONCLUSIONS: PMSCs could be induced into dermal fibroblasts by CTGF in vitro. PMSCs have the potential application in skin wound healing, and can be used as seed cells of dermal fibroblasts.

Diferenciação Celular/efeitos dos fármacos , Fator de Crescimento do Tecido Conjuntivo/farmacologia , Fibroblastos/citologia , Células-Tronco Mesenquimais/citologia , Células Cultivadas , Feminino , Fibroblastos/efeitos dos fármacos , Humanos , Células-Tronco Mesenquimais/efeitos dos fármacos , Placenta/citologia , Gravidez