Chitosan Alleviates LPS-induced Intestinal Barrier Damage by Regulating Tight Junction Proteins Via MAPK Signaling Pathway
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-α and IL-β in 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.
万方数据
维普
