ABSTRACT
Aim To provide references for clinical trials dose and rational drug use by evaluating mitochondrial toxicity of bentysrepinine on HepG2 cells.Methods Mitochondrial toxicity of bentysrepinine on HepG2 cells was cmomprehensively evaluated by measuring proliferation inhibition rate, lactic acid content in culture supernatant, reactive oxygen species(ROS) content, mitochondrial membrane potential (MMP) variation and the activity of mitochondrial respiratory chain complex enzymes Ⅰ to Ⅳ.Results The half inhibitory concentration of bentysrepinine of HepG2 cells was 359 μmol·L-1.Compared with the control group, bentysrepinine could reduce the MMP, raise the level of lactic acid, increase the content of ROS and lower the activity of mitochondrial respiratory chain complex enzymes Ⅰ to Ⅲ with the concentration of 400 μmol·L-1(196 mg·L-1), showing an obvious mitochondrial toxicity.Compared with lamivudine and adefovir dipivoxil, bentysrepinine exerted no influence on indexes above with the same concentration 100 μmol·L-1.Conclusions Bentysrepinine shows an obvious mitochondrial toxicity on HepG2 cells with the concentration of 400 μmol·L-1.This mitochondrial toxicity is not presented with the concentration of 200 μmol·L-1.It shows that the safety range of bentysrepinine about mitochondrial toxicity is relatively wide.The test plays a guiding role in clinical trial dose design as well as clinical treatment.
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 effect of bentysrepinine (Y101) metabolites on improving binding affinity of HBV DNA polymerase. Methods: The binding mode of Y101 and its metabolites with DNA polymerase has been driven by hydrophobic interaction. Results: Two compounds, T2 and T4, exhibited the improvement of the binding affinity to HBV DNA polymerase protein, which suggests that the inhibitory activity against HBV DNA polymerase protein can be enhanced. Conclusion: The variant docking poses of T2 and T4 might imply the novel recognition of inhibitory effects of T2 and T4, in comparison with Y101.
ABSTRACT
Bentysrepinine (Y101), a derivative of repensine, is a novel di-peptide structure isolated from Dichondra repens. In vitro and in vivo tests exhibited that bentysrepinine markedly inhibited DNA-HBV and cccDNA activities. The binding mode of Y101 and repensine with DNA polymerase was driven by hydrophobic interactions. This might provide novel recognition of inhibitory effect of Y101 against HBV, though its inhibition mechanism needs to be validated by bio-assay at cellular level and of polymerase activity. Preliminary docking study suggested that Y101 might be able to inhibit HIV inverse transcriptase, also have the potential to interact with DNA polymerase and HCV NS5B polymerase.