同型半胱氨酸调控MEK-ERK-MLCK通路影响结肠炎大鼠肠黏膜通透性的实验研究  

Effect of homocysteine on the intestinal permeability by regulating MEK-ERK-MLCK signal transduction in experimental colitis rats

作　　者：丁少桢 丁浩[1] 梅俏[1] 刘晓昌[1] 胡静[1] 胡咏梅[1] 许建明[1] 

机构地区：[1]安徽医科大学第一附属医院消化内科,安徽合肥230022

出　　处：《中国药理学通报》2016年第4期498-502,共5页Chinese Pharmacological Bulletin

基　　金：国家自然科学基金资助项目(No81470809);杨森科学研究委员会中国分会研究基金(No2012JRCC消化02)

摘　　要：目的探讨同型半胱氨酸(homocysteine,Hcy)是否通过调控MEK-ERK-MLCK通路影响结肠炎大鼠肠黏膜通透性的机制。方法 SD大鼠分为4组,A组为正常对照组(NS皮下注射+NS灌肠),B组为正常对照+Hcy注射组(Hcy皮下注射+NS灌肠),C组为TNBS模型组(NS皮下注射+TNBS灌肠),D组为TNBS模型+Hcy注射组(Hcy皮下注射+TNBS灌肠)。建立高Hcy血症的实验性结肠炎大鼠模型,实验结束时取大鼠结肠组织病理学检查,并进行结肠匀浆检测MPO活性,采用Western blot方法检测大鼠小肠组织中MEK、ERK、p-ERK、MLCK、p-MLCK的蛋白表达水平,采用RT-q PCR方法检测大鼠小肠组织中MLCK mRNA表达。结果与正常对照组及模型对照组相比,TNBS模型+Hcy皮下注射组大鼠DAI及HI评分增高,结肠匀浆MPO活性增高,小肠黏膜组织MEK、ERK、p-ERK、MLCK、p-MLCK蛋白表达水平增加,MLCK mRNA相对表达量增加。结论 Hcy增加实验性结肠炎大鼠肠黏膜通透性,可能与调控MEK-ERKMLCK信号通路有关。Aim To investigate whether Hcy influenced the intestinal mucosal permeability by regulating MEKERK-MLCK pathway. Methods SD rats were divided into 4 groups: normal group,normal + Hcy group,TNBS / ethanol group,TNBS / ethanol + Hcy group. Experimental colitis model with hyperhomocystinemia was established in rats with intracolonic administration of TNBS and subcutaneous injection of Hcy. The colonic mucosal tissue was collected for histopathological examination and activity of myeloperoxidase( MPO). The protein expression of MLCK,p-MLCK,MEK,ERK and p-ERK in intestinal mucosal tissues was examined by Western blot method. The mRNA expression of MLCK was examined by RT-q PCR method. Result Compared with the normal group and TNBS group,the DAI and HI scores and the MPO activity were increased in TNBS / ethanol + Hcy group( P < 0. 01). Western blot and RT-q PCR showed that expression of MLCK,p-MLCK,MEK,ERK and p-ERK increased in small intestine in TNBS / ethanol + Hcy group. Conclusion Hcy can increase intestinal permeability in TNBS-induced colitis rats by regulating the expression of MEK-ERKMLCK signal pathway.

关 键 词：同型半胱氨酸 炎症性肠病 肠黏膜通透性 紧密连接 肌球蛋白轻链激酶 细胞外信号调节激酶 

分 类 号：R-322[医药卫生] R322.45