Toll样受体4单克隆抗体对急性期溃疡性结肠炎小鼠结肠黏膜Toll样受体4介导的核因子-κB信号通路的影响  

Protective effects of toll like receptor 4 monoclonal antibodies on gut mucosal nuclear factor kappa B signaling pathway in mice with dextran sulfate sodium-induced acute ulcerative colitis

作　　者：刘懿[1] 王磊[1] 张志军[1] 孙旭[1] 黄剑平[1] 陈坚[1] 岳文杰[1] 李娟 董乐 钟良 

机构地区：[1]复旦大学附属华山医院消化科,上海200040

出　　处：《上海医学》2009年第8期702-705,共4页Shanghai Medical Journal

基　　金：上海市科学技术委员会基础研究重点课题(07JC14004)

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。Objective To evaluate the effects of toll like receptor 4 monoclonal antibodies （TLR4mAb） on phosphorylated IKB kinase（p-IKK）and nuclear factor kappa B（NF-κB）in NF-KB 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 （DAD 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 ①Compared 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）. ②The expression of protein p-IKK and the activity of NF-KB 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.

关 键 词：溃疡性结肠炎 Toll样受体4单克隆抗体 核因子-κB抑制蛋白激酶 核因子-ΚB 小鼠 

分 类 号：R574.62[医药卫生—消化系统]