Exercise alters the gut microbiome and microbial metabolites: Implications for colorectal cancer and inflammatory bowel disease

Abstract

Introduction Exercise training reduces colon cancer and inflammatory bowel diseases (IBD), but the mechanisms remain unknown. We hypothesized that acute and chronic exercise would alter the gut microbiota and its associated metabolome in a beneficial way. Methods Mice exercised for 6 weeks with access to voluntary wheels (VWR; n = 10), or were forcibly run on a treadmill running (FTR; n = 10). A control group remained sedentary (SED; n = 9). The conserved bacterial 16s rRNA gene was isolated from the feces and cecum and sequenced using high-throughput Illumina Miseq. In another experiment, mice were randomized to sedentary (SED, n = 10), acute moderate (MOD, n = 10) or high intensity running (HI, n = 10). Mice were euthanized 45 min post and cecal contents were analyzed for short chain fatty acids (SCFA) by GC-MS. Results Exercise training differentially altered the community structure of the microbiome at both intestinal sites ( p 0.05 ). Further evaluation revealed that exercise altered many bacterial taxa in both the feces and the cecum. Notably, voluntary exercise reduced ceca and fecal concentrations of Turicibacter spp., a genus of bacteria implicated in ulcerative colitis in humans and mice. Acute, HI (but not MOD) exercise increased the levels of potentially beneficial acetate, propionate, and butyrate, compared to SED ( p 0.05 ). Conclusion Acute and chronic exercise invokes changes in the microbiome and metabolome that may be beneficial to the prevention or treatment of IBD and colon cancer.