Protective Effects of Protopanaxatriol Saponins on Ulcerative Colitis in Mouse Based on UPLC-Q/TOF-MS Serum and Colon Metabolomics

Ulcerative colitis (UC) is a chronic, nonspecific inflammation of the bowel that mainly affects the mucosa and submucosa of the rectum and colon. Ginsenosides are the main active ingredients in ginseng and show many therapeutic effects in anti-inflammatory diseases, cancer, and nervous system regulation. Protopanaxatriol saponin (PTS) is an important part of saponins, and there is no research on its pharmacological effects on colitis. In this study, a model of ulcerative colitis in mice was induced by having mice freely drink 3.5% dextran sodium sulfate (DSS) solution, and UPLC-Q-TOF-MS-based metabolomics methods were applied to explore the therapeutic effect and protective mechanism of PTS for treating UC. The results showed that PTS could significantly prevent colon shortening and pathological damage and alleviate abnormal changes in UC mouse physiological and biochemical parameters. Moreover, PTS intervention regulated proinflammatory cytokines such as TNF-α, IL-6, and IL-1 in serum, and MPO and NO in colon. Interestingly, PTS could significantly inhibit UC mouse metabolic dysfunction by reversing abnormal changes in 29 metabolites and regulating eleven metabolic pathways. PTS has potential application in the treatment of UC and could alleviate UC in mice by affecting riboflavin metabolism, arachidonic acid metabolism, glycerophospholipid metabolism, retinol metabolism, and steroid hormone biosynthesis and by regulating pentose and glucuronate conversion, linoleic acid metabolism, phenylalanine metabolism, ether lipid metabolism, sphingolipid metabolism, and tyrosine metabolism, which points at a direction for further research and for the development of PTS as a novel natural agent.