Radix Pueraria lobata polysaccharide relieved DSS-induced ulcerative colitis through modulating PI3K signaling

[Display omitted] •PPL is a relatively low molecular weight polysaccharide.•PPL can ameliorate DSS-induced acute UC.•PPL can regulate plasma metabolism and dysbiosis of gut microbiota.•The effects of PPL were abolished after the knockdown of the PI3K gene. Polysaccharides are the essential active constituents of Radix Pueraria lobata. Numerous studies have shown that polysaccharides can play important roles in ulcerative colitis (UC). This study aimed to determine the protective effects of Radix Pueraria lobata polysaccharide (PPL) against UC. The pharmacological effects of PPL on the dextran sulfate sodium (DSS)-induced UC mice, changes in gut microbiota and metabolism, and DSS-induced Caco-2 cell injury were assessed in this study. Both the PPL inhibited the DSS-induced inflammation both in vivo and in vitro. Mechanistically, PPL inhibited inflammation by decreasing the activation of p-PI3K. Knocking down the PI3K gene resulted in abolishing the inhibitory effects of PPL on mouses and Caco-2 cells. The study concluded that the effects of PPL were completely dependent on PI3K.