title: Different dose-dependent mechanisms are involved in early cyclosporine a-induced cholestatic effects in hepaRG cells.
abstract: Mechanisms involved in drug-induced cholestasis in humans remain poorly understood. Although cyclosporine A (CsA) and tacrolimus (FK506) share similar immunosuppressive properties, only CsA is known to cause dose-dependent cholestasis. Here, we have investigated the mechanisms implicated in early cholestatic effects of CsA using the differentiated human HepaRG cell line. Inhibition of efflux and uptake of taurocholate was evidenced as early as 15 min and 1 h respectively after addition of 10μM CsA; it peaked at around 2 h and was reversible. These early effects were associated with generation of oxidative stress and deregulation of cPKC pathway. At higher CsA concentrations (≥50μM) alterations of efflux and uptake activities were enhanced and became irreversible, pericanalicular F-actin microfilaments were disorganized and bile canaliculi were constricted. These changes were associated with induction of endoplasmic reticulum stress that preceded generation of oxidative stress. Concentration-dependent changes were observed on total bile acid disposition, which were characterized by an increase and a decrease in culture medium and cells, respectively, after a 24-h treatment with CsA. Accordingly, genes encoding hepatobiliary transporters and bile acid synthesis enzymes were differently deregulated depending on CsA concentration. By contrast, FK506 induced limited effects only at 25-50μM and did not alter bile canaliculi. Our data demonstrate involvement of different concentration-dependent mechanisms in CsA-induced cholestasis and point out a critical role of endoplasmic reticulum stress in the occurrence of the major cholestatic features.
authors: Inserm UMR991, Foie, Métabolisme et Cancer, Rennes, France Université de Rennes 1, Rennes, France.
authors: Ahmad
authors: A
authors: Sharanek
authors: Inserm UMR991, Foie, Métabolisme et Cancer, Rennes, France Université de Rennes 1, Rennes, France.
authors: Pamela Bachour-El
authors: PB
authors: Azzi
authors: Inserm UMR991, Foie, Métabolisme et Cancer, Rennes, France Université de Rennes 1, Rennes, France.
authors: Houssein
authors: H
authors: Al-Attrache
authors: Inserm UMR991, Foie, Métabolisme et Cancer, Rennes, France Université de Rennes 1, Rennes, France.
authors: Camille C
authors: CC
authors: Savary
authors: ERL Inserm U1157/UMR7203, Faculté de Medecine Pierre et Marie Curie, Site Saint Antoine, Paris, France.
authors: Lydie
authors: L
authors: Humbert
authors: ERL Inserm U1157/UMR7203, Faculté de Medecine Pierre et Marie Curie, Site Saint Antoine, Paris, France.
authors: Dominique
authors: D
authors: Rainteau
authors: Inserm UMR991, Foie, Métabolisme et Cancer, Rennes, France Université de Rennes 1, Rennes, France.
authors: Christiane
authors: C
authors: Guguen-Guillouzo
authors: Inserm UMR991, Foie, Métabolisme et Cancer, Rennes, France Université de Rennes 1, Rennes, France andre.guillouzo@univ-rennes1.fr.
authors: André
authors: A
authors: Guillouzo
mesh_terms: D000199:Actins / Q000378:metabolism; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D002779:Cholestasis / Q000139:chemically induced* / Q000235:genetics / Q000378:metabolism; D016572:Cyclosporine / Q000633:toxicity*; D004305:Dose-Response Relationship, Drug; D059865:Endoplasmic Reticulum Stress / Q000187:drug effects / Q000235:genetics; D015870:Gene Expression / Q000235:genetics; D006801:Humans; D007166:Immunosuppressive Agents / Q000633:toxicity*; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism; D010766:Phosphorylation; D017382:Reactive Oxygen Species / Q000378:metabolism; D013656:Taurocholic Acid / Q000378:metabolism / Q000494:pharmacology; D059008:Time-Lapse Imaging
chemical_list: D000199:Actins; D007166:Immunosuppressive Agents; D017382:Reactive Oxygen Species; D013656:Taurocholic Acid; D016572:Cyclosporine; D020928:Mitogen-Activated Protein Kinases
keywords: bile acids; cPKC signaling; endoplasmic reticulum stress; hepatocytes; oxidative stress; tacrolimus; transporters