Anti-inflammatory effects of Forsythia suspensa in dextran sulfate sodium-induced colitis

Ethnopharmacological relevance: Forsythia suspensa Fructus (FS) is used to treat various inflammatory disorders in traditional Oriental medicine, including gastrointestinal diseases, but its therapeutic potential in ulcerative colitis is unclear. Thus, we investigated any potential therapeutic effects of FS against intestinal inflammation and the bioactive constituents in FS. Materials and methods: After the induction of colitis using 3% dextran sulfate sodium, FS (100 mg/kg/day) was administered orally during the experimental period. We evaluated body weight, bloody diarrhea, colon length, and pro-inflammatory cytokine levels. Subsequently, the bioactive constituents of FS were identified using UPLC/MS/MS. Results: FS significantly decreased the body weight loss, colon length shortening, and tumor necrosis factor-alpha and interleukin-6 elevations induced by colitis compared with the negative control (P < 0.05). Moreover, FS improved the colitis-induced histopathological damage to the colon, including epithelial necrosis, infiltration of inflammatory cells, ulceration, and submucosal edema. In phytochemical analyses, 7 flavonoids, 9 lignans, 13 phenolics, and 2 triterpenes were identified by comparison with the retention times and mass fragmentations of authentic standards. Conclusions: We demonstrated beneficial effects of FS and its constituents, suggesting their potential for treatment of intestinal inflammation. These data could provide useful information for managing ulcerative colitis.