title: Combined Stimulation with the Tumor Necrosis Factor α and the Epidermal Growth Factor Promotes the Proliferation of Hepatocytes in Rat Liver Cultured Slices.
abstract: The culture liver slices are mainly used to investigate drug metabolism and xenobiotic-mediated liver injuries while apoptosis and proliferation remain unexplored in this culture model. Here, we show a transient increase in LDH release and caspase activities indicating an ischemic injury during the slicing procedure. Then, caspase activities decrease and remain low in cultured slices demonstrating a low level of apoptosis. The slicing procedure is also associated with the G0/G1 transition of hepatocytes demonstrated by the activation of stress and proliferation signalling pathways including the ERK1/2 and JNK1/2/3 MAPKinases and the transient upregulation of c-fos. The cells further progress up to mid-G1 phase as indicated by the sequential induction of c-myc and p53 mRNA levels after the slicing procedure and at 24 h of culture, respectively. The stimulation by epidermal growth factor induces the ERK1/2 phosphorylation but fails to activate expression of late G1 and S phase markers such as cyclin D1 and Cdk1 indicating that hepatocytes are arrested in mid-G1 phase of the cell cycle. However, we found that combined stimulation by the proinflammatory cytokine tumor necrosis factor α and the epidermal growth factor promotes the commitment to DNA replication as observed in vivo during the liver regeneration.
authors.affiliation: Covance Laboratory SAS, 2-8 rue de Rouen, Z.I. de Limay-Porcheville, 78440 Porcheville, France.
authors.forename: Francis
authors.initials: F
authors.lastname: Finot
authors.forename: Régis
authors.initials: R
authors.lastname: Masson
authors.forename: Fabienne
authors.initials: F
authors.lastname: Desmots
authors.forename: Catherine
authors.initials: C
authors.lastname: Ribault
authors.forename: Nicole
authors.initials: N
authors.lastname: Bichet
authors.forename: Joan A
authors.initials: JA
authors.lastname: Vericat
authors.forename: Patricia
authors.initials: P
authors.lastname: Lafouge
authors.forename: Christiane
authors.initials: C
authors.lastname: Guguen-Guillouzo
authors.forename: Pascal
authors.initials: P
authors.lastname: Loyer