[Protective effect of an apoptosis inhibitor in a new model of hepatitis induced by interleukin-4 in the rat]. / Effet protecteur d'un peptide inhibiteur de l'apoptose dans un nouveau modèle d'hépatite induite par l'interleukine-4 chez le rat.

ABSTRACT

OBJECTIVES: Interleukin-4 is a cytokine with pleiotropic effects on many cells. The effects of its expression on the liver remain unclear. To obtain organ-localized cytokine expression and analyze its effect on the liver, recombinant adenovirus with coding sequences of interleukin-4 were transduced to rat livers. METHODS: Adenovirus with coding sequences of rat interleukin-4 were injected into the portal vein of Wistar rats. Microscopic examination of the liver was performed. The effects of interleukin-4 were confirmed in vitro on primary cultured rat hepatocytes. The same analysis was performed after intraperitoneal injection of l'YVADcmk, an inhibitor of the interleukin 1 converting enzyme. RESULTS: Interleukin-4 expression due to the recombinant adenovirus produced dose-related, potentially lethal, severe hepatitis. This hepatitis was characterized by a leucocyte infiltrate mainly composed of eosinophilic polymorphonuclear and mast cells with numerous apoptotic hepatocytes. Intraperitoneal injection of YVADcmk decreased hepatocyte apoptosis and biological hepatitis and prevented death. CONCLUSION: These results suggested that YVADcmk might be used in fulminant hepatitis in which apoptosis is predominant.