Comparative study of cytochrome P450 expression in three permanent human hepatocytes / 中国药理学与毒理学杂志

ABSTRACT

OBJECTIVE To investigate the expression differences of seven cytochrome P450 (CYP) isoforms between L02, LX-2 and HepG2 cells and identify the most suitable cell type for different CYP researches. METHODS L02, LX-2 and HepG2 cells were treated with omeprazole (Ome), dexamethasone(Dex), phenobarbital sodium (Phe), isoniazid (Iso) and rifampicin (Rif) at 5, 10, 20 and 40 μmol • L-1. Cell viability was analyzed by CCK-8 assay. The gene expressions of CYP1A2, CYP2B6, CYP2C9, CYP2C19, CYP2D6, CYP2E1 and CYP3A4 in LX-2 cells were assessed by real-time quantitative PCR (RT-qPCR). The protein expressions of these seven CYP isoforms in L02, LX-2 and HepG2 cells were assessed by Western blotting. Furthermore, CYP3A4 activity in the three types of cells treated with Rif 5, 10, 20 and 40 μmol • L-1 for 24 h was validated by Luciferin-PFBE. RESULTS Cell viabilities of all the three hepatocytes were over 80% when exposed to Ome, Dex, Phe, Iso and Rif (≤40 μmol • L-1) for 24 h. According to the RT-qPCR, Phe could significantly enhance the gene expressions of CYP2B6 (P<0.05) and CYP2D6 (P<0.01) in LX-2 cells. The results of Western blotting exhibited protein expression differences of seven CYP isoforms between L02, LX-2 and HepG2 cells treated with Ome, Dex, Phe, Iso and Rif (≤40 μmol-L-1) for 24 h. CYP2C9 [Integrated absorbance (IA)=1.58±0.07], CYP2C19 (IA= 0.95±0.03) and CYP3A4 (IA=1.29±0.05) had higher expression abundances in L02 cells, CYP2B6 (IA= 1.48±0.01) and CYP2D6 (IA=1.46±0.02) in LX-2 cells, and CYP1A2 (IA=1.62±0.19) and CYP2E1 (IA= 1.49±0.10) in HepG2 cells. Additionally, CYP3A4 activity in L02, LX-2 and HepG2 cells could not be up-regulated by Rif. CONCLUSION The most suitable cell type for different CYP researches is L02 for CYP2C9, CYP2C19 and CYP3A4, LX-2 for CYP2B6 and CYP2D6, HepG2 for CYP1A2 and CYP2E1, respectively.