title: Disruption of BSEP Function in HepaRG Cells Alters Bile Acid Disposition and Is a Susceptive Factor to Drug-Induced Cholestatic Injury.
abstract: In the present study, we characterized in vitro biosynthesis and disposition of bile acids (BAs) as well as hepatic transporter expression followed by ABCB11 (BSEP) gene knockout in HepaRG cells (HepaRG-KO cells). BSEP KO in HepaRG cells led to time-dependent BA accumulation, resulting in reduced biosynthesis of BAs and altered BA disposition. In HepaRG-KO cells, the expression of NTCP, OATP1B1, OATP2B1, BCRP, P-gp, and MRP2 were reduced, whereas MRP3 and OCT1 were up-regulated. As a result, BSEP KO altered the disposition of BAs and subsequently underwent adaptive regulations of BA synthesis and homeostasis to enable healthy growth of the cells. Although BSEP inhibitors caused no or slight increase of BAs in HepaRG wild type cells (HepaRG-WT cells), excessive intracellular accumulation of BAs was observed in HepaRG-KO cells exposed to bosentan and troglitazone, but not dipyridamole. LDH release in the medium was remarkably increased in HepaRG-KO cultures exposed to troglitazone (50 μM), suggesting drug-induced cellular injury. The results revealed that functional impairment of BSEP predisposes the cells to altered BA disposition and is a susceptive factor to drug-induced cholestatic injury. In total, BSEP inhibition might trigger the processes but is not a sole determinant of cholestatic cellular injury. As intracellular BA accumulation is determined by BSEP function and the subsequent adaptive gene regulation, assessment of intracellular BA accumulation in HepaRG-KO cells could be a useful approach to evaluate drug-induced liver injury (DILI) potentials of drugs that could disrupt other BA homeostasis pathways beyond BSEP inhibition.
authors.forename: Xi
authors.initials: X
authors.lastname: Qiu
authors.forename: Yueping
authors.initials: Y
authors.lastname: Zhang
authors.forename: Tongtong
authors.initials: T
authors.lastname: Liu
authors.forename: Hong
authors.initials: H
authors.lastname: Shen
authors.affiliation: Life Science and Technology Center, Sigma-Aldrich , St. Louis, Missouri 63103, United States.
authors.forename: Yongling
authors.initials: Y
authors.lastname: Xiao
authors.affiliation: Life Science and Technology Center, Sigma-Aldrich , St. Louis, Missouri 63103, United States.
authors.forename: Maureen J
authors.initials: MJ
authors.lastname: Bourner
authors.affiliation: Life Science and Technology Center, Sigma-Aldrich , St. Louis, Missouri 63103, United States.
authors.forename: Jennifer R
authors.initials: JR
authors.lastname: Pratt
authors.affiliation: Life Science and Technology Center, Sigma-Aldrich , St. Louis, Missouri 63103, United States.
authors.forename: David C
authors.initials: DC
authors.lastname: Thompson
authors.forename: Punit
authors.initials: P
authors.lastname: Marathe
authors.forename: W Griffith
authors.initials: WG
authors.lastname: Humphreys
authors.forename: Yurong
authors.initials: Y
authors.lastname: Lai
mesh_terms: D000074020:ATP Binding Cassette Transporter, Subfamily B, Member 11; D018528:ATP-Binding Cassette Transporters / Q000235:genetics / Q000378:metabolism*; D001647:Bile Acids and Salts / Q000378:metabolism*; D002460:Cell Line; D056486:Chemical and Drug Induced Liver Injury / Q000235:genetics / Q000378:metabolism*; D002779:Cholestasis / Q000378:metabolism; D006801:Humans; D008099:Liver / Q000378:metabolism; D008954:Models, Biological; D012307:Risk Factors
chemical_list: C093491:ABCB11 protein, human; D000074020:ATP Binding Cassette Transporter, Subfamily B, Member 11; D018528:ATP-Binding Cassette Transporters; D001647:Bile Acids and Salts
keywords: HepaRG cells; bile acid homeostasis; bile acids; bile salt export pump (BSEP); cholestasis; drug-induced liver injury (DILI); transporters