Metabolomics combined with mass spectrometry imaging decode the novel role of Gastrodia elata Blume on ulcerative colitis

Gastrodia elata Blume, a homologous substance of medicine and food, has been reported to exert multiple health benefits. This study aimed to investigate the beneficial role of Gastrodia elata Blume extract (GE) on ulcerative colitis (UC) from the perspective of gut microbiota by metabolomics and mass spectrometry imaging. Gut microbiota analysis showed that GE alleviated UC in a gut microbiota-dependent manner. Metabolomics showed that GE increased the levels of microbial tryptophan metabolites including kynurenic acid, 3-hydroxykynurenic acid, serotonin, etc. Matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI) confirmed the spatial distribution of these metabolites in colon. Western blot analysis further confirmed that these metabolites modulated by GE drove the activation of the AhR/NLRP3 signaling axis. Taken together, these findings demonstrated that GE modulated gut microbiota-derived tryptophan metabolites to attenuate UC, and support the application of Gastrodia elata Blume as a viable dietary resource for the treatment of UC.