Integrated analysis of effect of daisaikoto, a traditional Japanese medicine, on the metabolome and gut microbiome in a mouse model of nonalcoholic fatty liver disease

Abstract

Dysregulation of lipid metabolism and diabetes are risk factors for nonalcoholic fatty liver disease (NAFLD), and the gut-liver axis and intestinal microbiome are known to be highly associated with the pathogenesis of this disease. In Japan, the traditional medicine daisaikoto (DST) is prescribed for individuals affected by hepatic dysfunction. Herein, we evaluated the therapeutic potential of DST for treating NAFLD through modification of the liver and stool metabolome and microbiome by using STAM mice as a model of NAFLD. STAM mice were fed a high-fat diet with or without 3 % DST for 3 weeks. Plasma and liver of STAM, STAM with DST, and C57BL/6J ("Normal") mice were collected at 9 weeks, and stools at 4, 6, and 9 weeks of age. The liver pathology, metabolome and stool microbiome were analyzed. DST ameliorated the NAFLD activity score of STAM mice and decreased the levels of several liver lipid mediators such as arachidonic acid and its derivatives. In normal mice, nine kinds of family accounted for 94.1 % of microbiome composition; the total percentage of these family was significantly decreased in STAM mice (45.6 %), and DST administration improved this imbalance in microbiome composition (65.2 %). In stool samples, DST increased ursodeoxycholic acid content and altered several amino acids, which were correlated with changes in the gut microbiome and liver metabolites. In summary, DST ameliorates NAFLD by decreasing arachidonic acid metabolism in the liver; this amelioration seems to be associated with crosstalk among components of the liver, intestinal environment, and microbiome.

Keywords: Daisaikoto; Gut microbiome; Metabolome; Nonalcoholic fatty liver disease; Traditional Japanese medicine.