Effects of Saposhnikovia divaricata (Turcz.) Schischk extract on inflammation and gut microbial composition in DSS-induced colitis

Abstract

Inflammatory Bowel Disease (IBD), a chronic inflammation in the gastrointestinal tracts, affects up to 1 in 200 individuals per year. Most current clinical drugs for IBD lead to research for new possible treatments due to their adverse effects. Root of Saposhnikovia divaricata (Turcz.) Schischk (SD) has been used as a medicinal herb with its anti-inflammatory and analgesic effects. In this study, we investigated the effect of SD extracts on inflammation and gut microbiota modulation in vitro and colitis-induced mice. We purified seven compounds from methanol extract of SD roots (MESD), and found MESD and two compounds; deltoin and 3-O-angeloylhamaudol, reduced level of nitric oxide in Raw 264.7 mouse macrophages. Oral administration of MESD lowered pro-inflammatory cytokines, IL-1β and TNFα, in the serum and the colon in dextran sulfate sodium (DSS)-induced IBD mouse model. Furthermore, MESD significantly shifted the gut microbial composition. DSS treatment significantly increased the abundance of pathogens and decreased the butyrate producing bacteria. MESD decreased the abundance of genera Clostridium sensu stricto 1 and enriched some of predicted metabolic activities such as chondroitin sulfate degradation. These results suggest that MESD may ameliorate the DSS-induced colitis inflammation by regulating the compositions and functions of gut microbiota in mice.