Anti-Inflammatory Potential of Wampee (Clausena lansium (Lour.) Skeels) Polyphenol Extract in Ulcerative Colitis: Gut Microbiota and TLR4-p38 MAPK/NF-κB Signaling Axis Regulation

The consumption of wampee has traditionally been utilized to alleviate gastrointestinal inflammation and associated disorders; however, its exact mechanism has remained unknown. The aim of this study was to elucidate the therapeutic efficacy and underlying mechanism of wampee polyphenol extract (WPE) in dextran sulfate sodium (DSS)-induced ulcerative colitis (UC). The findings revealed that WPE alleviated diverse symptoms of UC, regulated various inflammatory cytokines, and effectively protected the colon tissue structure and barrier integrity, thereby inhibiting LPS translocation. Moreover, WPE restored the richness and diversity of gut microbiota and optimized its structure at the phylum and genus levels, causing a notable improvement in short- chain fatty acid (SCFA) metabolism, particularly acetic acid, propionic acid, and butyric acid. Consequently, WPE was demonstrated to effectively suppress the LPS-induced TLR4-p38 MAPK/NF-κB signaling pathway by modulating gut microbiota and SCFA metabolism. These findings provided a theoretical basis for the use of wampee as a potential functional natural food for UC.