Objective:To investigate the role of rheum tanguticum polysaccharide(RTP)in treating ulcerative colitis(UC)by improving intestinal flora.Methods:UC model was established,rats were divided into normal control group,model group and RTP treatment group.The integrity of colonic mucosa,submucosa and muscularis were observed by HE staining.Expressions of TNF-α,IL-6,IL-8 and IL-1β in serum were assessed by ELISA.16S rRNA sequencing was performed to analyze the composition and differences of intestinal flora in rats.Results:UC rats had symptoms such as loose stools,blood in the stool,anal filth,chills and mental malaise.RTP treatment could significantly improve the symptoms and reduce DAI scores(P<0.05).HE staining showed that the colonic struc-ture of UC rats was necrotic and inflammatory cells infiltrated submucosa.RTP treatment could significantly promote the repair and regeneration of mucosal epithelium.RTP could significantly inhibit inflammatory response and downregulate the expression of inflam-matory factors in UC rats(P<0.05).Composition and abundance of intestinal flora in UC rats were significantly different from that of normal control group.Staphylococcus was significantly increased,while Collinsella,Allobaculum,Chlamydia and Holdemanella were significantly decreased.RTP treatment could improve intestinal flora,reduce the abundance of Staphylococcus,and increase the abundance of Collinsella,Allobaculum,Chlamydia and Holdemanella.Conclusion:RTP can be used to treat UC in rats by inhibiting inflammation and improving intestinal flora.

Objective:To investigate the role of rheum tanguticum polysaccharide(RTP)in treating ulcerative colitis(UC)by improving intestinal flora.Methods:UC model was established,rats were divided into normal control group,model group and RTP treatment group.The integrity of colonic mucosa,submucosa and muscularis were observed by HE staining.Expressions of TNF-α,IL-6,IL-8 and IL-1β in serum were assessed by ELISA.16S rRNA sequencing was performed to analyze the composition and differences of intestinal flora in rats.Results:UC rats had symptoms such as loose stools,blood in the stool,anal filth,chills and mental malaise.RTP treatment could significantly improve the symptoms and reduce DAI scores(P<0.05).HE staining showed that the colonic struc-ture of UC rats was necrotic and inflammatory cells infiltrated submucosa.RTP treatment could significantly promote the repair and regeneration of mucosal epithelium.RTP could significantly inhibit inflammatory response and downregulate the expression of inflam-matory factors in UC rats(P<0.05).Composition and abundance of intestinal flora in UC rats were significantly different from that of normal control group.Staphylococcus was significantly increased,while Collinsella,Allobaculum,Chlamydia and Holdemanella were significantly decreased.RTP treatment could improve intestinal flora,reduce the abundance of Staphylococcus,and increase the abundance of Collinsella,Allobaculum,Chlamydia and Holdemanella.Conclusion:RTP can be used to treat UC in rats by inhibiting inflammation and improving intestinal flora.