壳寡糖经MAPK信号调控紧密连接蛋白缓解LPS诱导的肠屏障损伤  

Chitosan Alleviates LPSinduced Intestinal Barrier Damage by Regulating Tight Junction Proteins Via MAPK Signaling Pathway

作　　者：谢慧丽 吴莲云 巨向红[1] 刘晓曦 李有全 李寅 高元 周秋 汤瑞凡 雍艳红[1] XIE Huili;WU Lianyun;Ju Xianghong;LIU Xiaoxi;LI Youquan;LI Yin;GAO Yuan;ZHOU Qiu;TANG Ruifan;YONG Yanhong(College of Coastal Agriculture,Guangdong Ocean University,Zhanjiang Guangdong 524088)

机构地区：[1]广东海洋大学滨海农业学院,广东湛江524088

出　　处：《广东畜牧兽医科技》2024年第6期41-49,共9页Guangdong Journal of Animal and Veterinary Science

基　　金：国家自然科学基金面上项目(32273077)。

摘　　要：该试验旨在研究壳寡糖(COS)缓解LPS诱导的猪肠上皮细胞(IPEC-J2)屏障功能损伤的作用机制。试验分为4组,分别为对照组、LPS处理组、COS处理组、COS+LPS处理组。采用(1)CCK-8法测定肠上皮细胞增殖率;(2)TEER法和FITC-dextran法测定单层融合上皮通透性;(3)Western blot测定细胞紧密连接蛋白ZO-1、Occludin、Claudin-1和Claudin-4和丝裂原活化蛋白激酶(MAPK)信号通路关键蛋白ERK、JNK、P38及其磷酸化蛋白表达水平。结果表明:1)在LPS刺激下,IPEC-J2的增殖率显著下降,COS预处理能显著抑制LPS诱导的IPEC-J2增殖率下降(P<0.01)。2)COS能增加肠单层融合上皮的电阻率,并显著改善LPS诱导的肠单层融合上皮电阻率下降和对FITC-dextran的透过率增加(P<0.01)。3)COS能显著抑制LPS诱导的IPEC-J2中TNF-α和IL-β的上调(P<0.01)。4)LPS刺激后,细胞紧密连接蛋白显著下调,而COS预处理能显著抑制LPS诱导的紧密连接蛋白ZO-1、Occludin、Claudin-1和Claudin-4下调;COS预处理能抑制LPS诱导的p-ERK表达下调。由此可见,壳寡糖具有明显的抗炎和黏膜保护功能;壳寡糖对炎性肠病的保护与紧密连接蛋白表达上调有关;壳寡糖经MAPK信号调控紧密连接蛋白表达而改善肠屏障损伤。The aim of this experiment was to investigate the mechanism of action of chitosan(COS)in alleviating LPS-induced impairment of porcine intestinal epithelial cell(IPEC-J2)barrier function.The experiment was divided into four groups,namely,control group,LPS-treated group,COS-treated group,and COS+LPS-treated group.The proliferation rate of intestinal epithelial cells was measured by(1)CCK-8 method;(2)TEER method and FITC-dextran method for monolayer fusion epithelial permeability;(3)Western blot for cellular tight junction proteins ZO-1,Occludin,Claudin-1,and Claudin-4 and mitogen-activated protein kinase(MAPK)and mitogen-activated protein kinase(MAPK),ERK,JNK,P38 and their phosphorylated protein expression levels.The results showed that 1)the proliferation rate of IPEC-J2 was significantly decreased under LPS stimulation,and COS pretreatment significantly inhibited the LPS-induced decrease in the proliferation rate of IPEC-J2(P<0.01).2)COS increased the resistivity of intestinal monolayer fusion epithelium and significantly ameliorated the LPS-induced decrease in intestinal monolayer fusion epithelium resistivity and the increase in permeability to FITC-dextran(P<0.01).3)COS significantly inhibited the LPS-induced up-regulation of TNF-αand IL-βin IPEC-J2(P<0.01).4)After LPS stimulation,cellular tight junction proteins were significantly down-regulated,while COS pretreatment significantly inhibited LPS-induced down-regulation of tight junction proteins ZO-1,Occludin,Claudin-1 and Claudin-4;COS pretreatment inhibited LPS-induced down-regulation of p-ERK expression.Thus,chitooligosaccharides have obvious anti-inflammatory and mucosal protective functions;the protection of chitooligosaccharides against inflammatory bowel disease is related to the up-regulation of tight junction proteins;chitooligosaccharides improve intestinal barrier damage by regulating tight junction proteins expression via MAPK signaling.

关 键 词：壳寡糖 紧密连接蛋白 MAPK 

分 类 号：S852.3[农业科学—基础兽医学]