Purpose/Background: Nutritional flow in the intestine is important to maintain intestinal tissue integrity and support the resident microbes. However, intestinal starvation, including fecal diversion, continues to be an integral part of colorectal surgery. Some documented detrimental effects of colonic starvation include decreased mucin, dysbiosis and bacterial translocation and local tissue atrophy. The systemic impact of fecal diversion on metabolism, immunity and microbiome health is poorly understood.
Methods/Interventions: To address the systemic effects of fecal diversion on metabolism, immunity and the colonic microbiome, I performed proximal loop colostomies in 15-week-old C57BL/6J male mice. Animals were fed one of four different diets, differing in nutritional composition or degree of processing, for two weeks prior to surgery. For each of six colostomy animals per diet, we characterized short-chain fatty acids by GC/MS, bacterial microbiome composition by 16S sequencing, and systemic inflammation by serum cytokines.
Results/Outcomes: Only eight days of colonic starvation by diverting colostomy led to significantly decreased bacterial load, by 16S qPCR, as well as differences in microbial community composition. We also found that serum TNF-α, G-CSF, and IL-6 levels, exhibited a diet-dependent effect with high-fat diet leading to the highest levels in colostomy, but not sham control, animals.
Conclusion/Discussion: Our results suggest that nutritional pre-habilitation shapes acute post-operative inflammation and colonic microbiome composition shortly after a diverting colostomy in a pre-clinical murine model of fecal diversion.
