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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: OBJECTIVE, METHODS, RESULTS. Meshes: Animals, Cells, Cultured, Cytokines, DNA-Binding Proteins, Drug Combinations, Gene Expression Regulation, Hepatocytes, I-kappa B Proteins, Inflammation Mediators, Lipopolysaccharides, Liver, Male, NF-KappaB Inhibitor alpha, NF-kappa B, Nitric Oxide, Nitric Oxide Synthase, Nitric Oxide Synthase Type II, Promoter Regions, Genetic, Rats, Rats, Wistar, S-Adenosylmethionine.
user
Does s-Adenosylmethionine modulate inducible nitric oxide synthase gene expression in rat liver and isolated hepatocytes? Context: Hepatocellular availability of S-adenosylmethionine, the principal biological methyl donor, is compromised in situations of liver damage. S-Adenosylmethionine administration alleviates experimental liver injury and increases survival in cirrhotic patients. The mechanisms behind these beneficial effects of S-adenosylmethionine are not completely known. An inflammatory component is common to many of the pathological conditions in which S-adenosylmethionine grants protection to the liver. This notion led us to study the effect of S-adenosylmethionine administration on hepatic nitric oxide synthase-2 induction in response to bacterial lipopolysaccharide and proinflammatory cytokines. The effect of S-adenosylmethionine on nitric oxide synthase-2 expression was assessed in rats challenged with bacterial lipopolysaccharide and in isolated rat hepatocytes treated with proinflammatory cytokines. Interactions between S-adenosylmethionine and cytokines on nuclear factor kappa B activation and nitric oxide synthase-2 promoter transactivation were studied in isolated rat hepatocytes and HepG2 cells, respectively. S-Adenosylmethionine attenuated the induction of nitric oxide synthase-2 in the liver of lipopolysaccharide-treated rats and in cytokine-treated hepatocytes. S-Adenosylmethionine accelerated the resynthesis of inhibitor kappa B alpha, blunted the activation of nuclear factor kappa B and reduced the transactivation of nitric oxide synthase-2 promoter.
assistant
Our findings indicate that the hepatoprotective actions of S-adenosylmethionine may be mediated in part through the modulation of nitric oxide production. Final Decision: yes