【摘要】 目的探讨Toll样受体4(TLR4)单克隆抗体(TLR4mAb)对葡聚糖硫酸钠(DSS)诱导的急性期溃疡性结肠炎(UC)小鼠肠黏膜TLR4介导的核因子(NF)-κB信号通路中磷酸化IκB激酶(p-IKK)及NF-κB的影响情况。方法30只BALB/c小鼠均分为正常对照组(A组)、UC模型组(B组)及低、中、高剂量TLR4mAb干预组(C、D、E组)。A组小鼠饮用蒸馏水7d;B、C、D、E组小鼠饮用5%DSS水溶液7d以制成UC模型。造模同时,C、D、E组小鼠分别腹腔注射低、中、高剂量TLR4mAb。造模及干预7d后处死小鼠,观察指标包括疾病活动指数(DAI)、结肠组织病理学评分(HPS)。采用Western印迹法检测各组肠黏膜p-IKK的蛋白表达,蛋白凝胶电泳迁移率变动分析法(EMSA法)检测NF-κB的活性变化。结果B组小鼠的结肠黏膜DAI及HPS均显著高于A组(P值均<0.01)。与模型组相比,使用TLR4mAb干预后中、高剂量组HPS有不同程度的缓解(P值均<0.01)。②与B组相比,D、E组的TLR4mAb后p-IKK表达及NF-κB的活性均显著下降(P值分别<0.05、0.01)。结论TLR4mAb可以减轻肠道炎症,发挥干预作用,其机制可能是通过抑制TLR4介导的NF-κB通路关键蛋白的表达,降低NF-κB的活性,继而减少下游炎性因子过度表达。更多还原

【Abstract】 Objective To evaluate the effects of toll like receptor 4 monoclonal antibodies(TLR4mAb)on phosphorylated IκB kinase(p-IKK)and nuclear factor kappa B(NF-κB)in NF-κB signaling pathway in mice with dextran sulfate sodium(DSS)-induced acute ulcerative colitis(UC).Methods Thirty male BALB/c mice were randomly assigned to five groups:normal control group(A),model group(B),low dose(C),medium dose(D),and high dose(E)TLR4mAb groups.Mice in group B,C,C,and E were given 5.0%(wt/wt)DSS solution for 7 days to induce acute intestinal inflammation,and those in group A were given distilled water freely.Group C,D,E received TLR4mAb injection of corresponding doses.Daily disease activity index(DAI)and histopathological score(HPS)were observed.The protein expression of p-IKK was examined by Western blotting assay,and the activity of NF-κB was measured by EMSA.Results ① Compared with group A,group B had markedly higher DAI and HPS(P<0.01).The HPS in group D and E was significantly lower than that of group B(P<0.01).② The expression of protein p-IKK and the activity of NF-κB in group D and E were significantly lower than those in group B(P<0.05 or 0.01).Conclusion TLR4mAb can ameliorate the DSS-induced colitis in mice through down-regulating the expression of p-IKK and the activity of NF-κB,reducing the downstream inflammatory factor expression.更多还原