酒精性肝纤维化核因子κB信号通路与性别的差异

Nuclear factor-κB signaling pathway and gender differences in alcoholic liver fibrosis

目的探讨酒精性肝纤维化的核因子(NF)-κB信号通路与性别差异的关系。方法将7~8周龄的C57BL/6 N小鼠随机分为:雄性正常组、雄性模型组,雌性正常组和雌性模型组各20只。正常组采用对照液体饲料喂养8周,模型组采用酒精液体饲料喂养8周,联合31.5%乙醇灌胃(每周两次,5 g/kg)建立酒精性肝纤维化模型。8周末处死小鼠,检测各组小鼠血清学谷丙转氨酶(ALT)及谷草转氨酶(AST)的活性,雌二醇(E2)和睾酮(T)的水平,天狼星红染色检测各组小鼠纤维化情况,HE染色观察肝组织病理学变化,免疫组织化学法检测NF-κB-P65和α平滑肌肌动蛋白(α-SMA)阳性面积率,免疫印迹法检测Ⅰ型胶原蛋白(collagenⅠ)、肿瘤坏死因子α(TNF-α)、磷酸化核因子κB-P65(p-NF-κB-P65)、核因子κB抑制因子α(IκBα)、磷酸化核因子κB抑制因子α(p-IκBα)的表达水平。结果雄性模型组ALT,AST酶活性和T的水平升高,E2的水平降低,胶原纤维增加,HE染色坏死积分升高,NF-κB-P65和α-SMA的阳性面积率增加,collagenⅠ,TNF-α、p-NF-κB-P65、p-IκBα的表达增加,IκBα的表达降低。结论酒精更容易导致雄性小鼠肝纤维化,这可能与加强IκBα磷酸化释放NF-κB,促使磷酸化NF-κB-p65增多,进一步激活NF-κB信号通路有关。

Objective To investigate the relationship between nuclear factor(NF)-κB signaling pathway and gender differences in alcoholic liver fibrosis.Methods C57BL/6 N mice at 7-8 weeks of age were randomly divided into:male normal group,male model group,female normal group and female model group of 20 mice each.The normal group was fed with control liquid diet for 8 weeks,and the model group was fed with alcoholic liquid diet for 8 weeks combined with 31.5%ethanol gavage(5 g/kg twice a week)to establish an alcoholic liver fibrosis model.The mice were executed at the end of 8 weekends,and the alanine aminotransferase(ALT),aspartate aminotransferase(AST)activity,estradiol(E_(2))and testosterone(T)levels were detected in each group,and the fibrosis was detected in each group by Sirius red staining,and liver histopathological changes were observed by HE staining.The postive area rate of NF-κB-P65 andα-SMA were detected by immunohistochemistry and the expression levels of collagenⅠ,tumor necrosis factor-α(TNF-α),phosphorylated nuclear factorκB-P65(p-NF-κB-P65),inhibitor of NF-κB(IκBα),and phosphorylated IκBα(p-IκBα)were detected by wes Western blotting.Results The male model group showed increased levels of ALT,AST enzyme activity and T,decreased levels of E_(2),increased collagen fibrils,increased HE staining necrosis score,increased positive area rate of NF-κB-P65 andα-smooth muscle actin(α-SMA),increased expression of collagenⅠ,TNF-α,p-NF-κB-P65,p-IκBαand decreased expression of IκBα.Conclusion Alcohol is more likely to cause liver fibrosis in male mice,which may be related to enhanced IκBαphosphorylation releasing NF-κB,contributing to increased phosphorylated NF-κB-P65 and further activation of NF-κB signaling pathway.