Abstract
1. Cell models expressing human drug transporters and enzymes are useful tools to understand the process of drug disposition in vitro. However, no study on transfected cells stably co-expressing human organic anion transporter 1 (hOAT1) and/or human cytochrome P450 1A2 (hCYP1A2) is available. In this study, cell models stably expressing hOAT1 and/or hCYP1A2 were established, and were used to investigate the interactions of ingredients of herbal medicines (IHMs) with hOAT1 and/or hCYP1A2.
2. The MDCK cells were stable transfected with recombinant plasmids expressing hOAT1 and/or hCYP1A2. Cellular uptake assay and CYP450 activity assay showed that the transfected cells were available. A marked high expression of hOAT1 and hCYP1A2 mRNA was also validated by quantitative RT-PCR. Totally 6 IHMs which significantly inhibited the activity of hOAT1 were screened out by employing hOAT1 expressing cells. The contribution of hOAT1 and hCYP1A2 to the toxicity of aristolochic acid I (AAI) was further determined. Compared to mock cells, all transfected cells showed a decrease in viability after being treated with AAI.
3. A method to establish transfected cell expressing drug metabolism enzymes and/or transporters was provided in our study. Three IHMs (dihydrotanshinone I, cryptotanshinone, and tanshinone I) were confirmed as novel inhibitors of hOAT1. Furthermore, a synergistic effect of hOAT1 and hCYP1A2 on AAI-induced toxicity was also observed in this investigation.
Declaration of interest
This project was supported by International Science & Technology Cooperation Program of China (2014DFE30050), Ministry of Science and Technology of China (2012ZX09506001-004), the Program for Zhejiang Leading Team of S&T Innovation Team (2011R50014), and the Fundamental Research Funds for the Central Universities of China Ministry of Education (2016XZZX001-08). The authors report no declarations of interest.