紧密连接蛋白Occludin表达与小鼠肠屏障功能障碍和炎性出血的关系  

The relationship between the expression of tight junction protein Occludin and intestinal barrier dysfunction and inflammatory hemorrhage in young mice.

作　　者：王莉芬 何伟 王懿凡 WANG Li-fen;HE Wei;WANG Yi-fan(The First District of Pediatrics,Qionghai People's Hospital,Qionghai Hainan 571400,China.)

机构地区：[1]琼海市人民医院儿科,海南琼海571400

出　　处：《临床和实验医学杂志》2021年第18期1908-1912,共5页Journal of Clinical and Experimental Medicine

基　　金：海南省自然科学基金(编号:2018619527)。

摘　　要：目的探讨紧密连接蛋白Occludin表达与小鼠肠屏障功能障碍和炎性出血的关系。方法以15只C57BL/6新生小鼠为研究对象,通过交替饮用3%葡聚糖硫酸钠(DSS)溶液和去离子水建立炎症性肠病模型,并根据实验设置分为对照组(正常小鼠+腹腔注射生理盐水)、模型组(模型小鼠+腹腔注射生理盐水)和Occludin转染组(模型小鼠+腹腔注射50μL Occludin过表达慢病毒载体)。注射1周后通过蛋白印迹分析各实验组小鼠体内紧密连接蛋白Occludin的表达。通过酶联免疫吸附试验(ELISA)试剂盒分析提取组织中促炎细胞因子肿瘤坏死因子-α(TNF-α)、白细胞介素(IL)-6和IL-1β的水平。通过异硫氰酸荧光素-葡聚糖(FITC-D)方法和血液中脂多糖(LPS)的浓度评估小鼠的肠屏障功能。通过免疫组织化学对小鼠肠组织进行评分。通过比较小鼠结肠长度与体重比评估结肠发育。通过逆转录聚合酶链式扩增(RT-PCR)实时分析凋蛋白p53、Bax和Bcl-2的mRNA表达。结果模型组较对照组中Occludin的蛋白表达降低(P<0.05),Occludin转染组较模型组Occludin的蛋白表达升高(P<0.05)。模型组较对照组中TNF-α、IL-6和IL-1β的水平升高(P<0.05),Occludin转染组较模型组TNF-α、IL-6和IL-1β的水平降低(P<0.05)。模型组较对照组中FITC-D和LPS升高(P<0.05),Occludin转染组较模型组FITC-D和LPS降低(P<0.05)。模型组较对照组中组织学评分和粪便出血评分升高(P<0.05),Occludin转染组较模型组相应评分降低(P<0.05)。模型组较对照组结肠长度与体重之比值降低(P<0.05),Occludin转染组较模型组比值升高(P<0.05)。模型组较对照组p53、Bax的mRNA表达升高,Bcl-2表达降低(P<0.05),Occludin转染组较模型组Bax的mRNA表达降低,Bcl-2表达升高(P<0.05)。结论紧密连接蛋白Occludin的过表达减轻了DSS引起的小鼠肠黏膜损伤,促进体内肠道形态和肠屏障完整性的更新。Objective To investigate the relationship between the expression of tight junction protein Occludin and intestinal barrier dysfunction and inflammatory hemorrhage in young mice.Methods Fifteen C57BL/6 newborn mice were used as the research objects.The inflammatory bowel disease model was established by drinking 3%dextran sodium sulfate(DSS)solution and deionized water alternately.According to the experimental settings,they were divided into control group(normal mice+intraperitoneal injection of saline),model group(model mice+intraperitoneal injection of saline)and Occludin transfection group(model mice+intraperitoneal injection of 50μL Occludin overexpression lentiviral vector).After 1 week of injection,the expression of tight junction protein Occludin in mice of each experimental group was analyzed by Western blotting.The levels of pro-inflammatory cytokines tumor necrosis factor alpha(TNF-α),interleukin(IL)-6 and IL-1βin the extracted tissues were analyzed by enzyme-linked immunosorbent assay(ELISA)kit.The intestinal barrier function of mice was evaluated by the FITC-D method and the concentration of LPS in the blood.The intestinal tissues of young mice were scored by immunohistochemistry.The colon development was evaluated by comparing the ratio of the length of the colon to the body weight of the young mice.Real-time analysis of mRNA expression of AP53,Bax and Bcl-2 by RT-PCR.Results The protein expression of Occludin in the model group was lower than that in the control group(P<0.05),and the protein expression of Occludin in the Occludin transfection group was higher than that in the model group(P<0.05).The levels of TNF-α,IL-6 and IL-1βin the model group were higher than those in the control group(P<0.05),and the levels of TNF-α,IL-6 and IL-1βin the Occludin transfection group were lower than those in the model group(P<0.05).The FITC-D and LPS in the model group were higher than those in the control group(P<0.05),and the FITC-D and LPS in the Occludin transfection group were lower than those in the m

关 键 词：小鼠 紧密连接蛋白OCCLUDIN 肠屏障 免疫组织化学 炎性出血 

分 类 号：R574[医药卫生—消化系统]