ABSTRACT
Objective: In this study, primary cultured human hepatocytes were used to study the induction of P450 enzyme by the sesquiterpene lactone derivative ACT001, which provided reference for the clinical use of ACT001. Methods Three batches of frozen primary human hepatocytes were inoculated and cultured, and CYP1A2, CYP2B6 and CYP3A4 were induced by ACT001. Real-time fluorescence quantitative PCR was used to determine the mRNA expression level of P450 enzyme, and the activity of P450 enzyme was determined by LC-MS/MS method. Results The expression level of P450 enzyme mRNA and the activity of P450 enzyme showed that the P450 enzyme induction model was successfully established. Compared with the control group, the CYP1A2 mRNA expression level and enzyme activity of ACT001 1 μmol/L and 6 μmol/L group showed no significant changes. The mRNA expression level of CYP1A2 in ACT001 30 μmol/L group was significantly decreased, and the enzyme activity was decreased, but not as significantly as that of mRNA. With the increase of ACT001 concentration, the expression level of CYP2B6 mRNA was gradually increased. Compared with the control group, the expression level of CYP2B6 mRNA in the ACT001 group at 30 μmol/L was significantly increased, which was seven times higher than that in the control group, and the increase of enzyme activity was four times higher than that in the control group, which was 40% higher than that in the phenobarbital sodium induction multiple. Compared with the control group, the CYP3A4 mRNA expression level of cells in the ACT001 1 μmol/L group was significantly increased, which was four times higher than that of the control group, but did not reach 40% of the positive inducer rifampicin, and the CYP3A4 mRNA expression level was decreased gradually with the increase of ACT001 concentration. At the same time, there was no significant increase in CYP3A4 enzyme activity after ACT001 administration at different concentrations, which was less than two times of that in the control group. Conclusion The data indicated that ACT001 had no induction potential for CYP1A2 and CYP3A4, and had potential for CYP2B6 induction. In combination with CYP2B6 substrates, it should be avoided in clinical combination therapy to reduce adverse reactions caused by P450-mediated drug drug interaction.
ABSTRACT
Bentysrepinine (Y101), a derivative of phenyalanine dipeptide, has a novel mechanism in the treatment of hepatitis B virus (HBV) infection with a good anti-HBV effect. In the present study, a fluorometric-based high throughput method using cytochrome P450 (CYP) screening kit was adopted to evaluate in vitro inhibition potential of Y101 on CYP isoenzymes by calculating remaining enzyme activities and inhibitory potential (IC50 values) using the determined values of fluorescence intensity. The result showed that Y101 exhibited little activity in the inhibition of CYP1A2, CYP3A4, CYP2C9, CYP2C19 and CYP2D6 (IC50 > 100 μmol·L-1). Y101 was used to treat human primary hepotocytes for 72 h, and the enzyme activities of CYP1A2, CYP2B6 and CYP3A4 were determined with a cocktail of probe substrates for the three CYP isoforms. The metabolites were simultaneously determined using a LC-MS/MS method. Y101 had no activity in the induction of CYP1A2, CYP2B6 and CYP3A4 on the basis of the following results:① The ratio of enzyme activities between test and control groups were all below than 1 (varied from 0.662 to 0.928); ② The induction potential of Y101 were lower than forty percent compared with that of positive groups. The above results suggest that Y101 has little activity in the regulation of metabolic drug-drug interactions based on the CYP isoform changes following co-administration of drugs.
ABSTRACT
Bentysrepinine (Y101), a derivative of phenylalanine dipeptide, is a novel drug candidate for the treatment of hepatitis B virus (HBV) infection. Our previous preclinical pharmacokinetic study showed that its in vivo absorption and distribution characteristics were probably related to transmembrane transport after Y101 was administered intragastically in rats. In this study, Caco-2 and MDCK-MDR1 cell models were used to investigate interactions between Y101 and P-gp through the apparent permeation coefficient (Papp) and efflux ratio (RE); the results showed that Y101 was a substrate of P-gp. In addition, gene-transfected cell models, HEK293-hOATP1B1, HEK293-hOATP2B1 and CHO-PEPT1 were used to evaluate the affinity to OATP1B1,
ABSTRACT
Objective: To study the mechanisms of absorption and transport of 3-acetyl-11-keto-β-boswellic acid (AKBA) from Boswellia carterif in Caco-2 cell, MDCK-MDR1, and MDCK-Wild cell models. Methods: The Caco-2, MDCK-MDR1, and MDCK-Wild cell monolayer models were used to study the bi-directional transport of AKBA in apical (AP)→basal (BL) or BL→AP; The concentration of AKBA was measured by LC-MS/MS and apparent permeability coefficient (Papp) was calculated. Results: Papp (AP→BL) and Papp (BL→AP) values of AKBA (50 μmol/L) in Caco-2 cell model were 7.9 × 10-7 and 1.5 × 10-7 cm/s, respectively; Papp (AP→BL) and Papp (BL→AP) values of AKBA (50 μmol/L) in MDCK-MDR1 cell model were 2.6 × 10-7 and 0.8 × 10-7 cm/s, respectively; Papp (AP→BL) and Papp (BL→AP) of AKBA (50 μmol/L) in MDCK-Wild cell model was 2.4 × 10-7 and 0.6 × 10-7 cm/s, respectively; The rates of efflux (RE) for AKBA in Caco-2 and MDCK-MDR1 cell monolayers were both smaller than 2. Conclusion: AKBA is not the substrate of P-gp and its absorption rate is low. AKBA is absorbed through the intestinal epithelial cells by active transport absorption and passive diffusion possibly.