Anti-inflammatory effects of purple sweet potato anthocyanin extract in DSS-induced colitis: modulation of commensal bacteria and attenuated bacterial intestinal infection

The purple sweet potato anthocyanin has been acknowledged for its beneficial effects on human inflammatory bowel diseases (IBD). Although the ability of anthocyanin in modulating gut microbiota has been reported, the interactions between bacterias modulated by anthocyanin and intestinal inflammation have not been fully elucidated. We aimed to ascertain whether the purple sweet potato anthocyanin extract (PSPAE) modulation of gut microbiota in the dextran sodium sulphate (DSS) induced model of mouse chronic colitis could result in the maintenance of intestinal homeostasis and protection against bacterial intestinal inflammation. The chronic colitis was induced by adding DSS in drinking water while given the mice PSPAE gavaged (20mg/kg). Effects on colon tissue damage, gut microbiota composition, tight junction protein, and cytokines were evaluated. PSPAE prevented the loss of Bifidobacterium and Lactobacillus and inhibited the increase of Gammaproteobacteria and Helicobacter upon DSS treatment. The non-pathogenic-dependent and pathogenic-dependent microenvironments were established upon treatment with broad-spectrum antibiotics. Both PSPAE treatment and non-pathogenic treatment modified the colonic expression of mouse tight junction proteins and maintained the architecture of the colon. However, the non-pathogen treatment could not attenuate the intestinal inflammatory. Moreover, the pathogen-dependent dysbiosis was exacerbated because of the enhancing colonization of pathogens like Helicobacter. The PSPAE exerted modulation of gut microbiota to maintain the gut microenvironment homeostasis in chronic DSS colitis mice, which may help to propose a new treatment that combines efficacy and reduction on the possibility of bacterial intestinal infection.