IRE1α和IRE1β在DSS诱导的小鼠慢性结肠炎中的表达及意义  

Expression and significance of IRE1α and IRE1β in DSS induced mouse chronic colitis

作　　者：戴发亮 董仕桢 轩青霞 陈梦露[1,3] 陈攀[1] 冯丹丹[1] 范永刚[1,2] 高强[1,4] 

机构地区：[1]河南科技大学临床医学院河南科技大学第一附属医院消化内科,洛阳471023 [2]河南科技大学临床医学院河南科技大学第一附属医院肝胆外科,洛阳471023 [3]河南科技大学临床医学院河南科技大学第一附属医院检验科,洛阳471023 [4]首都医科大学附属北京康复医院消化内科,北京100114

出　　处：《安徽医科大学学报》2017年第4期495-500,共6页Acta Universitatis Medicinalis Anhui

基　　金：国家自然科学基金(编号:81370487)

摘　　要：目的探讨肌醇需求酶1(IRE1)α和IRE1β在葡聚糖硫酸钠(DSS)诱导的小鼠慢性结肠炎中的表达及意义。方法选择8~10周龄的C57BL/6雌性小鼠随机分为两组:对照组10只,正常饮水;慢性炎症组10只,先给予1.0%DSS自由饮用7 d,然后正常饮水14 d如此作为一个周期,循环3个周期建立小鼠慢性结肠炎模型。通过疾病活动指数(DAI)评分、结肠长度测定和HE染色等方法评估肠道炎症程度。采用实时定量PCR技术检测小鼠结肠组织中炎症因子、内质网应激因子IRE1α、IRE1β、非剪接型X-盒结合蛋白1(XBP1u)、剪接型X-盒结合蛋白1(XBP1s)和黏蛋白(MUC)2 mRNA表达,免疫组织化学方法检测IRE1α、IRE1β和MUC2表达。结果对照组小鼠无肠炎表现,而慢性炎症组在3个周期末结肠出现炎症表现。实时定量PCR结果显示白介素(IL)-6、IL-8和肿瘤坏死因子(TNF)-αmRNA在慢性炎症组高于对照组(P<0.05);XBP1s和IRE1αmRNA在两组表达无明显差异;XBP1u mRNA在慢性炎症组表达低于对照组(P<0.05)。IRE1β和MUC2 mRNA在慢性炎症组表达均低于对照组(P<0.05)。IRE1α蛋白主要表达于结肠上皮的刷状缘、浆细胞等细胞的胞质中,其表达量在炎症组高于对照组,IRE1β蛋白和MUC2蛋白主要表达于结肠上皮细胞胞质中,两者表达量在炎症组低于对照组(P<0.05)。结论 IRE1α可能通过对XBP1进行剪接来参与肠道炎症反应,并且IRE1α还有可能通过其他机制来调节自身的表达来参与炎症过程;IRE1β和MUC2可能与结肠上皮的功能维持有关,在肠道炎症过程中IRE1β和MUC2表达功能受到抑制而影响炎症的发生和发展。Objective To investigate the expression and significance of IRE1α and IRE1β in chronic colitis induced by dextran sulphate sodium（DSS） in mice. Methods Seven-to-eight-week-old C57BL/6 mice were randomly divided into control group and chronic colitis group（n = 10 for each group）. Chronic colitis group was given1. 0% DSS free to drink for 7 days and then water for 14 days as a cycle. After three cycles a mouse model of chronic colitis was established. Mice in the control group was only given drinking water. Disease activity index（DAI）,colon length and pathological inflammation score of the colon were observed. The expression of pro-inflammation cytokines,IRE1α,IRE1β,XBP1 u,XBP1s and MUC2 mRNA were detected by real-time quantitative PCR,and the expression of IRE1α,IRE1β and MUC2 protein were evaluated by immunohistochemistry. Results There was no inflammation in mouse colon of the control group; whereas mice showed the inflammatory manifestations at the end of third cycle in mouse colon of the chronic colitis group. IL-6,IL-8 and TNF-α mRNA in chronic colitis group were significantly higher than that of the control group（P〈0. 05）. There was no significant difference in the expression of XBP1 s and IRE1 between the two groups. The expression of IRE1β,XBP1 u and MUC2 mRNA in mice with chronic colitis were significantly lower than that of control group（P〈0. 05）. The protein of IRE1α was mainly expressed in the cytoplasm of colonic epithelial brush margin and plasma cells and lymphocytes of some inflammatory cells. IRE1α protein in the colitis group was higher than that of the control group. The protein of IRE1β and MUC2 were mainly expressed in colonic epithelial cells,and their expression was decreased in chronic colitis group（P〈0. 05）. Conclusion ER stress molecule IRE1α may be involved in the intestinal inflammatory response by splicing XBP1,and regulate its own expression through other mechanisms to participate in the inflammatory process. The pathway of IRE1β/MUC2 is inhi

关 键 词：炎症性肠病 慢性结肠炎 IRE1α IRE1β 黏蛋白2 

分 类 号：R363[医药卫生—病理学] R574[医药卫生—基础医学]