The Peanut Skin Procyanidins Attenuate DSS-Induced Ulcerative Colitis in C57BL/6 Mice

Polyphenols from peanut skin have been reported to possess many beneficial functions for human health, including anti-oxidative, antibacterial, anticancer, and other activities. To date, however, its anti-inflammatory effect and the underlying mechanism remain unclear. In this study, the anti-inflammatory effect of peanut skin procyanidins extract (PSPE) and peanut skin procyanidins (PSPc) were investigated by a dextran sodium sulfate (DSS)-induced colitis mouse model. The results showed that both PSPE and PSPc supplementation reversed the DSS-induced body weight loss and reduced disease activity index (DAI) values, accompanied by enhanced goblet cell numbers and tight junction protein claudin-1 expression in the colon. PSPE and PSPc treatment also suppressed the inflammatory responses and oxidative stress in the colon by down-regulating IL-1β, TNF-α, and MDA expressions. Meanwhile, PSPE and PSPc significantly altered the gut microbiota composition by increasing the relative abundance of Clostridium XlVb and Anaerotruncus, and inhibiting the relative abundance of Alistipes at the genus level. PSPE and PSPc also significantly elevated the production of short-chain fatty acids (SCFAs) in mice with colitis. The correlation analysis suggested that the protective effects of PSPE and PSPc on colitis might be related to the alteration of gut microbiota composition and the formation of SCFAs. In conclusion, the current research indicates that supplementation of PSPE and PSPc could be a promising nutritional strategy for colitis prevention and treatment.