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AIM:To investigate effects of hepatotropic growth factors on radical production in rat hepatocytes during sepsis.METHODS:Rat hepatocytes,isolated by collagenase perfusion,were incubated with a lipopolysaccharide(LPS)-containing cytokine mixture of interleukin-1β,tumor necrosis factor-α and interferon-γ to simulate sepsis and either co-incubated or pre-incubated with hepatotropic growth factors,e.g.hepatocyte growth factor,epidermal growth factor and/or transforming growth factor-α.Cells were analyzed for glutathione levels.Culture supernatants were assayed for produc-tion of reactive oxygen intermediates(ROIs) as well as NO2-,NO3-and S-nitrosothiols.To determine cellular damage,release of aspartate aminotransferase(AST) into the culture medium was analyzed.Activation of nuclear factor(NF)-κB was measured by electrophoretic mobility shift assay.RESULTS:Rat hepatocytes treated with the LPS-containing cytokine mixture showed a significant increase in ROI and nitrogen oxide intermediate formation.AST leakage was not significantly increased in cells treated with the LPS-containing cytokine mixture,independent of growth-factor co-stimulation.However,pretreatment with growth factors significantly reduced AST leakage and ROI formation while increasing cellular glutathione.Application of growth factors did not result in increased NF-κB activation.Pretreatment with growth factors further increased formation of NO2-,NO3-and S-nitrosothiols in hepatocytes stimulated with LPS-containing cytokine mixture.Thus,we propose that,together with an increase in glutathione increased NO2-,NO3-formation might shift their metabolism towards non-toxic products.CONCLUSION:Our data suggest that hepatotropic growth factors positively influence sepsis-induced hepatocellular injury by reducing cytotoxic ROI formation via induction of the cellular protective antioxidative systems.
AIM: To investigate effects of hepatotropic growth factors on radical production in rat hepatocytes during sepsis. METHODS: Rat hepatocytes, isolated by collagenase perfusion, were incubated with a lipopolysaccharide (LPS) -containing cytokine mixture of interleukin-1β, tumor necrosis factor-α and interferon-γ to simulate sepsis and either co-incubated or pre-incubated with hepatotropic growth factors, eg hepatocyte growth factor, epidermal growth factor and / or transforming growth factor-α. Cells were analyzed for glutathione levels. Culture supernatants were assayed for produc-tion of reactive oxygen intermediates (ROIs) as well as NO2-, NO3- and S- nitrosothiols. To determine cellular damage, release of aspartate aminotransferase (AST) into the culture medium was analyzed. Activation of nuclear factor (NF) κB was measured by electrophoretic mobility shift assay .RESULTS: Rat hepatocytes treated with the LPS-containing cytokine mixture showed a significant increase in ROI and nitrogen oxide intermedia te formation. AST leakage was not significantly increased in cells treated with the LPS-containing cytokine mixture, independent of growth-factor co-stimulation. However, pretreatment with growth factors significantly reduced AST leakage and ROI formation while increasing cellular glutathione. Application of growth Factors did not result in increased NF-κB activation. Treatment with growth factors further increased formation of NO2-, NO3-and S-nitrosothiols in hepatocytes stimulated with LPS-containing cytokine mixture .hus, we propose that, together with an increase in glutathione increased NO2-, NO3-formation might shift their metabolism towards non-toxic products. CONCLUSION: Our data suggest that hepatotropic growth factors positively influenced sepsis-induced hepatocellular injury by reducing cytotoxic ROI formation via induction of the cellular protective antioxidative systems.