title: Evaluation of CYP3A4 inhibition and hepatotoxicity using DMSO-treated human hepatoma HuH-7 cells.
abstract: A human hepatoma cell line (HuH-7) was evaluated as a metabolically competent cell model to investigate cytochrome P450 3A4 (CYP3A4) inhibition, induction, and hepatotoxicity. First, CYP3A4 gene expression and activity were determined in HuH-7 cells under three culture conditions: 1-week culture, 3-week culture, or 1 % dimethyl sulfoxide (DMSO) treatment. HuH-7 cells treated with DMSO for 2 weeks after confluence expressed the highest CYP3A4 gene expression and activity compared to the other two culture conditions. Furthermore, CYP3A4 activity in DMSO-treated HuH-7 cells was compared to that in a human hepatoma cell line (HepG2/C3A) and human bipotent progenitor cell line (HepaRG), which yielded the following ranking: HepaRG > DMSO-treated HuH-7 >> HepG2/C3A cells. The effects of three known CYP3A4 inhibitors were evaluated using DMSO-treated HuH-7 cells. CYP3A4 enzyme inhibition in HuH-7 cells was further compared to human recombinant CYP3A4, indicating similar potency for reversible inhibitors (IC 50 within 2.5-fold), but different potency for the irreversible inhibitor. Next, induction of CYP3A4 activity was compared between DMSO-treated HuH-7 and HepaRG cells using two known inducers. DMSO-treated HuH-7 cells yielded minimal CYP3A4 induction compared to that in the HepaRG cells after 48-h treatments. Finally, the cytotoxicity of five known hepatotoxicants was evaluated in DMSO-treated HuH-7, HepG2/C3A, and HepaRG cells, and significant differences in cytotoxic sensitivity were observed. Overall, DMSO-treated HuH-7 cells are a valuable model for medium- or high-throughput screening of chemicals for CYP3A4 inhibition and hepatotoxicity.
authors.affiliation: Division of Toxicology, Office of Applied Research and Safety Assessment, Center for Food Safety and Applied Nutrition, US Food and Drug Administration, Laurel, MD, USA. yitong.liu@fda.hhs.gov.
authors.forename: Yitong
authors.identifier: http://orcid.org/0000-0002-4300-4349
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Division of Toxicology, Office of Applied Research and Safety Assessment, Center for Food Safety and Applied Nutrition, US Food and Drug Administration, Laurel, MD, USA.
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Flynn
authors.affiliation: Division of Pre-Clinical Innovation, National Center for Advancing Translational Sciences, National Institutes of Health, Bethesda, MD, USA.
authors.forename: Menghang
authors.initials: M
authors.lastname: Xia
authors.affiliation: Division of Toxicology, Office of Applied Research and Safety Assessment, Center for Food Safety and Applied Nutrition, US Food and Drug Administration, Laurel, MD, USA.
authors.forename: Paddy L
authors.initials: PL
authors.lastname: Wiesenfeld
authors.affiliation: Division of Public Health Informatics & Analytics, Office of Analytics and Outreach, Center for Food Safety and Applied Nutrition, US Food and Drug Administration, College Park, MD, USA.
authors.forename: Martine S
authors.initials: MS
authors.lastname: Ferguson
mesh_terms: D006528:Carcinoma, Hepatocellular / Q000201:enzymology; D045744:Cell Line, Tumor; D051544:Cytochrome P-450 CYP3A / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism*; D065607:Cytochrome P-450 Enzyme Inhibitors / Q000494:pharmacology*; D004121:Dimethyl Sulfoxide / Q000494:pharmacology*; D015870:Gene Expression / Q000187:drug effects; D056945:Hep G2 Cells; D022781:Hepatocytes / Q000187:drug effects* / Q000201:enzymology*; D006801:Humans; D008113:Liver Neoplasms / Q000201:enzymology; D018675:Toxicity Tests / Q000379:methods*
chemical_list: D065607:Cytochrome P-450 Enzyme Inhibitors; D051544:Cytochrome P-450 CYP3A; C510163:CYP3A4 protein, human; D004121:Dimethyl Sulfoxide
keywords: CYP3A4; DMSO; Hepatotoxicity; HuH-7 cells; Induction; Inhibition