Type 5 Resistant Starch Can Effectively Alleviate Experimentally Induced Colitis in Mice by Modulating Gut Microbiota

Resistant starch (RS) has been shown to modulate intestinal microbiota in animal models in ways that could reduce the effects of dysbiosis-related diseases. However, the mechanism of how this is achieved is not understood. The present study aimed to reveal the mechanism of how RS mitigates dextran sulfate sodium (DSS)-induced colitis in mice by using a starch-lipid complex (RS type 5), with an RS type 2 from high-amylose maize starch as a comparison. Both RS5 and RS2 induced changes in the diversity and composition of the gut bacteria, leading to the alleviation of the induced colitis symptoms including decreasing the loss in body weight, disease activity index score, and colonic shortening. The levels of inflammatory cytokines were modulated and accompanied by an increase in goblet cell numbers and thickening of the intestinal mucus layer. RS5 was more effective, compared to RS2, in alleviating all of the colitis symptoms, mainly through improving the gut microflora dysbiosis and stimulating the generation of short-chain fatty acids (SCFAs). Our study shows that RS5 could effectively alleviate the symptoms of colitis, highlighting a potential use for RS5, particularly in relieving inflammatory bowel disease.