Effects of a Short-Term High-Fat Diet on Microbiota Biodiversity of the Small and Large Intestines of C57BL/6SPF Mice.

Long-term high-fat diet (HFD) promotes the formation of excess body weight and disorders of lipid metabolism and causes persistent dysbiotic changes in the intestinal microbial community. Changes in eating behavior, endocrine and immune functions of the host are associated with changes in the structure and functional activity of microbial communities. Short-term HFD may also influence the composition and function of the intestinal microbiota, but data on this issue are limited, and most papers are focused on the study of the large intestinal microbiota. The present study examined the effect of short-term HFD (4 weeks) on the structure of microbial communities in the small and large intestines of 24 mice. High-throughput metagenomic sequencing was performed on 48 samples of small and large intestine contents. It was revealed that short-term HFD in mice contributed to impaired glucose tolerance and increased the diversity of microbiota in the colon, but not of the small intestine, and also led to changes in the representation of certain microbial taxa (in particular Tenericutes and Verrucomicrobia). Furthermore, short-term HFD increased blood glucose levels compared to control mice (fed a normal diet), but did not affect lipid metabolism. The results will help to assess the contribution of environmental factors to the structure of microbial communities of the small and large intestines and may also be useful for correcting dysbiotic conditions, including when prescribing therapeutic diets (for example, a ketogenic diet).