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中促炎因子及信号传导通路的影响  

Influence of Toll like receptor 4 monoclonal antibodies on proinflammatory cytokines and Toll like receptor 4 signaling pathway in intestinal mucosa of mice with DSS-induced acute ulcerative colitis

作　　者：刘懿[1] 张志军[1] 王磊[1] 陈坚[1] 孙旭[1] 钟良[1] 孙大裕[1] 

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》2008年第4期270-274,共5页Shanghai Medical Journal

基　　金：上海市科学技术委员会基金资助(05ZR14021)

摘　　要：目的探讨Toll样受体4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小鼠结肠黏膜的促炎因子肿瘤坏死因子(TNF)-α、干扰素(IFN)-γ、白细胞介素(IL)-1β以及信号传道通路P38MAPK、磷酸化P38MAPK、c-fos、c-jun蛋白表达情况的影响。方法18只BALB/c小鼠分为对照(A)、急性期溃疡性结肠炎模型(B)及干预(C)组。A组小鼠饮用蒸馏水7 d;B、C组小鼠饮用5%DSS水溶液7 d,以产生急性期溃疡性结肠炎模型。C组小鼠在造模开始的同时,腹腔内注射TLR4mAb,观察其干预作用。造模及干预7 d后处死小鼠,观察指标包括疾病活动指数(DAI)、结肠组织病理学炎症损伤评分(HPS),采用逆转录-聚合酶链反应检测各组结肠黏膜TNF-αmRNA、IFN-γmRNA、IL-1βmRNA表达,采用Western印迹法测定各组结肠黏膜P38MAPK、磷酸化P38MAPK、c-fos、c-jun蛋白表达。结果①造模第8天,B组的DAI明显高于A、C组(P值均<0.01),A与C组间的差异无统计学意义(P>0.05)。C组小鼠予TLR4mAb干预1周后,HPS明显小于B组(P<0.01),而与A组的差异无统计学意义(P>0.05)。②B组TNF-αmRNA、IFN一γmRNA和IL-1βmRNA均显著高于A和C组(P值均<0.01),而后两组间的差异均无统计学意义(P值均>0.05)。③B组的P38MAPK蛋白、c-jun蛋白表达明显高于A组(P值均<0.01)和C组(P值分别<0.01和0.05),后两组间的差异也有统计学意义(P值均<0.01)。3组间磷酸化P38MAPK、c-fos蛋白表达的差异均无统计学意义(P值均>0.05)。结论TLR4mAb可能通过抑制TLR4-P38MAPK-c-fos/c-jun信息传导通路,降低信号传导通路中P38MAPK、c-jun蛋白的表达,下调小鼠结肠黏膜促炎因子TNF-αmRNA、IFN-γmRNA、IL-1βmRNA表达而发挥其干预作用。Objective To evaluate the influence of Toll like receptor 4 monoclonal antibodies （TLR4mAb） on the levels of proinflammatory cytokines （tumor necrosis factor [TNF]-α, Interferon [IFN]-γ and interleukin [IL]-1β） and the protein expression involved in TLR4 P38MAPK-c-fos/c-jun signaling pathway （P38MAPK, phosphorylated P38MAPK,c-fos, and c-junexpression） in the intestinal mucosa of mice with dextran sulfate sodium （DSS）-induced ulcerative colitis （UC） . Methods Eighteen male BALB/c mice were randomly assigned to three groups., normal control group （A）, UC model group（B） and intervention group （C）. Animals in Group B and group C were only given 5.0%（wt/wt） DSS solution as drinking water for 7 days to induce acute intestinal inflammation; those in Group A had free access to distilled water. Mice in Group C also received intraperitoneal TLR4mAb injection every 48h since the start of DSS exposure. The animals were sacrificed on the 7th day of the experiment. The disease activity index （DAI, for all the 7 days） and histopathological score （HPS） were examined. The mRNA expression Of TNF-α, IFN-γ, and IL-1β were detected by RT-PCR; the protein expression of P38 MAPK and phosphorylated P38 MAPK, c-fos, and c-jun were measured by Western Blot. Results①On the 8 th day of DSS exposure, DAI in group B was significantly higher than those in the group A and C （both P〈0.01） ; there was no significant difference between the later 2 groups. One week after TLR4mAB intervention, HPS in group C was significantly smaller than that in group B （P〈0.01）, and had no significant difference compared with Group A. ② The levels of TNF-α, IFN-γ and IL-1β mRNA in group B were significantly higher than those in group A and C （both P〈0.01）, with no significant difference found between the later 2 groups. ③The protein expression of P38MAPK and c-jun in group B were significantly higher than those in group A and C （P〈0.01 or P〈0.05） ; significant difference was also

关 键 词：溃疡性结肠炎 Toll样受体4单克隆抗体 肿瘤坏死因子-Α 干扰素-Γ 白细胞介素-Β 

分 类 号：R574.62[医药卫生—消化系统] R392.3[医药卫生—内科学]