American Ginseng Attenuates Colitis-Associated Colon Carcinogenesis in Mice: Impact on Gut Microbiota and Metabolomics

Inflammatory bowel disease is a risk factor for colorectal cancer initiation and development. In this study, the effects of American ginseng on chemically induced colitis and colon carcinogenesis were evaluated using an azoxymethane (AOM)/dextran sulfate sodium (DSS) mouse model. During the acute phase on day 15, the oral administration of ginseng (15 and 30 mg/kg/day) significantly suppressed AOM/DSS-induced colitis, as demonstrated by the disease activity index and colon tissue histology. During the chronic phase in week 13, AOM/DSS-induced tumor multiplicity was significantly suppressed by ginseng. Ginseng significantly attenuated the increase of inflammatory cytokines, such as IL1 alpha, IL1 beta, IL6, G-CSF, and GM-CSF. Serum metabolomics data in the PCA plots showed good separation between the AOM/DSS model and ginseng-treated mice, and the most important endogenous metabolite changes were identified. The 16S rRNA data showed that after AOM/DSS, the microbiome community in the model group was obviously changed, and ginseng inhibited these changes. Fecal metabolomics analysis supported these findings. In conclusion, oral ginseng significantly decreased AOM/DSS-induced colitis and colon carcinogenesis by inhibiting inflammatory cytokines and restoring the metabolomics and microbiota profiles accordingly. Selective endogenous small molecules could be used as biomarkers to elucidate the effects of ginseng treatment. (C) 2016 AACR.