中文摘要：

[目的]通过体外细胞实验,研究氧化型谷胱甘肽[glutathione（Oxidized）,GSSG]通过抑制细胞内肿瘤坏死因子（tumor necrosis factor-α,TNF-α）介导的核转录因子（nuclear transcription factors kappa B,NF-κB）的活化诱导肝细胞死亡的作用机制。[方法]以人肝细胞株Hep G2为细胞模型,利用乳酸脱氢酶（lactate dehydrogenase,LDH）测定法及Hoechst染色法检测GSSG、TNF-α作用后细胞培养液中LDH活性及细胞凋亡情况。通过蛋白免疫印迹法（western blot,WB）检测细胞中蛋白质谷胱甘肽化水平、IκB激酶β（inhibitor kappa B kinase-β,IKK-β）蛋白表达水平及其磷酸化水平。通过酶联免疫法（enzyme linked immunosorbent assay,ELISA）检测GSSG、还原型谷胱甘肽（glutathione,GSH）水平及NF-κB（P65）的结合活性。并利用实时定量荧光PCR（real time PCR,RT-PCR）检测NF-κB目标基因的表达情况。[结果]（1）H2O2作用后可显著提高Hep G2细胞内GSSG水平。（2）GSSG可以显著增加Hep G2细胞对TNF-α杀伤作用的敏感性。（3）GSSG通过氧化巯基使蛋白质谷胱甘肽化水平显著升高。（4）GSSG抑制Hep G2细胞内TNF-α介导的NF-κB活化。（5）GSSG通过谷胱甘肽化修饰IKK-β抑制NF-κB的活性。[结论]氧化应激产物GSSG通过抑制TNF-α介导的NF-κB活化诱导肝细胞死亡。这可能是一种新的非酒精性脂肪性肝病（nonalcoholic fatty liver disease,NAFLD）的发病机制。

英文摘要：

[Objective] To study the role of GSSG in hepatocyte death induced by inhibiting of TNF-α-mediated the NF-κB activation.[Methods]Human liver cell line HepG2 was used to establish the cell model. The effect of GSSG on TNF-α-induced cell death was determined by lactate dehydrogenase（LDH）release and Hoechst Staining. The intracellular levels of GSSG-protein adducts, and the protein expression of IKK- β and phospho-IKK-β was determined by Western blotting. The intranuclear NF-κB（p65） and its DNA binding activity were detected by ELISA. The level of GSSG and GSH was detected by ELISA too.Use Real time PCR to detect the expression of NF-κB target genes. [Results]（1）GSSG significantly increased the sensitivity of HepG2 cells for the killing effect of TNF-α.（2）H_2O_2can significantly increase the level of GSSG in HepG2 cells.（3）GSSG significantly increased the level of glutathione-protein adducts by oxidizing sulfhydryl.（4）GSSG inhibited TNF-α-mediated NF-κB（p65） activation in HepG2 cells.（5）GSSG inhibited NF-κB activity by glutathione modification of IKK-β. [Conclusions]Oxidative stress plays a key role in the development of non-alcoholic fatty liver disease, and produces GSSG as a hepatocyte-sensitizing factor, which inhibits TNF-α-mediated NF-κB anti-apoptotic signaling pathway in hepatocytes, thus inducing alcoholic liver damage.This may be a new pathogenesis of nonalcoholic fatty liver disease.