摘要
AIM:To investigate whether naofen is involved in tumor necrosis factor(TNF)-α-mediated apoptosis of hepatocytes induced by lipopolysaccharide(LPS).METHODS:In vivo,rats were treated with LPS or antiTNF-αantibody,whereas in vitro,primary hepatocytes and Kupffer cells(KCs)were separately isolated from rat livers using collagenase perfusion,and primary hepatocytes were cultured in medium containing LPS or TNF-α,or in conditioned medium from LPS-treated KCs(KC-CM)/KC-CM+anti-TNF-αantibody.Naofen and TNF-αmRNA expression was examined by realtime reverse transcription-polymerase chain reaction.Immunoblotting was used to measure protein expression.Hepatocyte apoptosis was determined by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling(TUNEL)assay.RESULTS:LPS significantly induced both naofen expression and caspase-3 activity in the rat liver,which coincided with an increase in the number of TUNELpositive hepatocytes.The increase of TNF-αexpression induced by LPS was preceded by increases in naofen and caspase-3 activity.Elevation of naofen expression and caspase-3 activity was abrogated by pretreatment with anti-TNF-αantibody.In KCs,LPS caused an increase in TNF-αthat was almost consistent with that in the liver of LPS-treated rats.In hepatocytes,neither LPS nor TNF-αalone affected either naofen expression or caspase-3 activation.The incubation of hepatocytes with KC-CM significantly enhanced both naofen expression and caspase-3 activity.Moreover,the effects of the KC-CM-induced increase in naofen expression and caspase-3 activity were blocked by anti-TNF-αantibody.CONCLUSION:TNF-αreleased from KCs treated with LPS may induce hepatic naofen expression,which then stimulates hepatocellular apoptosis through activation of caspase-3.
AIM: To investigate whether naofen is involved in tumor necrosis factor (TNF)-α-mediated apoptosis of hepatocytes induced by lipopolysaccharide (LPS).
