Study On Shugan Jianpi Decoction For IBS-D Mediated Intestinal Epithelial Cells Apoptosis/Autophagy To Maintain Intestinal Barrier

Objective: To study the significance of intestinal epithelial cell apoptosis and autophagy in maintaining the intestinal barrier integrity of Diarrhea-predominant Irritable Bowel Syndrome model rats,and to explore the mechanism of action on Shugan Jianpi Decoction in treating liver spleen and spleen deficiency syndrome IBS-D rats.Methods: 48 male Sprague-Dawley rats were randomly divided into groups according to body weight: normal group,model group,low dose group,medium dose group,high dose group,and western medicine group.In addition to the normal group,the remaining group was treated with the IBS-D rat model by the combination of the succulent gavage and the restraint stress method,and the rats were given different concentrations of Shugan Jianpi Decoction and Pevimonium bromide.Next,the markers of apoptosis,autophagy and intestinal barrier of colonic epithelial cells in each group were detected.Specifically,the general condition of the rat(including body weight,activity,coat color,stool characteristics)was observed.Histopathological changes were observed by HE staining under light microscope.Mast cell activation was observed by mast cell specific staining method using toluidine blue method.The microstructure of colon tissue was observed by electron microscopy.The apoptosis rate was counted by Tunel staining.The expression of inflammatory factor IL-6,autophagy marker protein Beclin-1,tight junction protein Occludin and Claudin-1 was detected by immunohistochemistry(SABC).Results: The IBS-D model was successfully prepared,according to general conditions and histopathology under light microscopy.The mast cell-specific staining showed that the mast cell count of the model group was higher than that of the normal group(P<0.05),and the counts of the low,medium and high dose groups were lower than the model group(P<0.05).Under the electron microscope,the IECs microvilli were disordered,partially swollen and ruptured,autophagy was obvious,and the intercellular space was widened.In the low,medium and high dose groups,the IECs microvilli were arranged neatly,the autophagy was not obvious,and the intercellular space was tight.Tunel staining showed that the apoptotic rate of the model group was significantly higher than that of the normal group(P<0.05),and the apoptosis rate of the low,medium and high dose groups was lower than that of the model group(P<0.05).Immunohistochemistry showed that the expression of IL-6 and Beclin-1 was increased in the model group compared with the normal group(P<0.05),and Occludin and Claudin-1 were decreased(P<0.05);the expressions of IL-6 and Beclin-1 in the low,medium and high dose groups were lower than those in the model group(P<0.05),and Occludin and Claudin-1 were increased(P<0.05).Conclusion: In the pathogenesis of IBS-D,intestinal imbalance was involved in the stimulation of injury,and apoptosis was considered a key factor.Shugan Jianpi Decoction was used to treat IBS-D because it reduced mast cell activation,decreased IL-6 and Beclin-1 expression,and elevated Occludin and Claudin-1.The expression promotes autophagy balance,reduces intestinal epithelial cell apoptosis,maintains intestinal barrier integrity,and maintains intestinal homeostasis.