Alteration of the intestinal microbiota associated with the development of nonalcoholic steatohepatitis and sarcopenia in SHRSP5/Dmcr.

Sarcopenia, characterized by skeletal muscle atrophy, was previously considered age-related; however, it is also associated with other diseases. Nonalcoholic fatty liver disease (NAFLD) is known to cause sarcopenia, and its complications have been reported to affect prognosis. The intestinal microbiota of patients with NAFLD or sarcopenia has been found to be altered compared to that of healthy individuals. However, the alterations that occur when both diseases coexist in humans or experimental animals remain unclear. Therefore, this study aimed to determine the intestinal microbiota changes associated with NAFLD with sarcopenia in SHRSP5/Dmcr rats at the time of concomitant disease. Fecal samples were collected from the rectum of SHRSP5/Dmcr rats fed a normal diet (non-NAFLD and non-Sarcopenia, n = 5) or a high-fat and high-cholesterol diet (NAFLD and Sarcopenia, n = 5) for 20 weeks, and subjected to 16S rRNA analysis. In the NAFLD and sarcopenia group, the diversity of the intestinal microbiota was reduced; further, the bacterial species reported in patients with NAFLD or sarcopenia were also changed. At the family level, the abundances of Akkermansiaceae, Bacteroidaceae, and Tannerellaceae were significantly higher whereas Ruminococcaceae and Lactobacillaceae were decreased in the NAFLD and sarcopenia group. At the genus level, the abundances of Akkermansia, Bacteroides, Ruminococcus, and Parabacteroides were significantly higher whereas the abundance of Lactobacillus was significantly decreased in the NAFLD and sarcopenia group. Overall, these findings help improve the existing understanding regarding the intestinal microbiota changes observed in conditions where NASH and sarcopenia co-occur.