title: Evaluation of human hepatocytes under prolonged culture in a novel medium for the maintenance of hepatic differentiation: results with the model pro-inflammatory cytokine interleukin 6.
abstract: A major challenge for the evaluation of cytokine-induced down regulation of CYP gene expression in primary cultured hepatocytes is the spontaneous decrease in expression of the genes with culture duration. Based on our recent discovery that hepatocytes cultured for 7 days in a novel medium, Li's Differentiation Maintenance Medium (LDMM), would retain gene expression for markers of differentiation and most CYP isoforms at levels similar to those of the first day of culture, we examined the effects of the prototypical pro-inflammatory cytokine IL-6 in the "LDMM-stabilized (LS)" human hepatocyte model. The LS-human hepatocyte cultures were found to be responsive to IL-6 induction of the inflammatory gene marker, C-reactive protein (CRP), suggesting the expression of IL-6 receptors and the subsequent signaling pathways. Results from two independent laboratories with human hepatocytes from three donors demonstrated dose-dependent down regulation of the gene expression of several CYPs, i.e. 1A2, 2B6, 2C8, 2C9, 2C19, 2D6 and 3A4. The results suggest that the LS-human hepatocytes may represent a physiologically relevant experimental model for mechanistic investigation of the down-regulatory effects of inflammatory cytokines.
authors.forename: Albert P
authors.initials: AP
authors.lastname: Li
authors.forename: Qian
authors.initials: Q
authors.lastname: Yang
authors.forename: Hélène
authors.initials: H
authors.lastname: Vermet
authors.forename: Nathalie
authors.initials: N
authors.lastname: Raoust
authors.forename: Sylvie
authors.initials: S
authors.lastname: Klieber
authors.affiliation: In Vitro ADMET Laboratories LLC, 9221 Rumsey Road Suite 8, Columbia, Maryland 21045 (APL), USA. lialbert@invitroadmet.com.
authors.forename: Gérard
authors.initials: G
authors.lastname: Fabre
mesh_terms: D000328:Adult; D002097:C-Reactive Protein / Q000235:genetics / Q000378:metabolism; D002454:Cell Differentiation / Q000187:drug effects*; D002478:Cells, Cultured; D003470:Culture Media / Q000378:metabolism*; D003577:Cytochrome P-450 Enzyme System / Q000235:genetics / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D015536:Down-Regulation; D005260:Female; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects; D022781:Hepatocytes / Q000187:drug effects* / Q000201:enzymology; D006801:Humans; D018836:Inflammation Mediators / Q000494:pharmacology*; D015850:Interleukin-6 / Q000494:pharmacology*; D007527:Isoenzymes; D008297:Male; D008875:Middle Aged; D013997:Time Factors; D015854:Up-Regulation; D055815:Young Adult
chemical_list: D003470:Culture Media; C508600:IL6 protein, human; D018836:Inflammation Mediators; D015850:Interleukin-6; D007527:Isoenzymes; D002097:C-Reactive Protein; D003577:Cytochrome P-450 Enzyme System