Three Kampo medicines-bofutsushosan, boiogito, and daisaikoto-have different effects on host fat accumulation and the intestinal microbiota in a high-fat-diet-induced mouse model of obesity.

Inhibiting body fat accumulation is important for the prevention of obesity. In Japan, three Kampo medicines are commonly used to treat obesity: bofutsushosan, boiogito, and daisaikoto. To compare the influences of these Kampo medicines on the intestinal microbiota, it is necessary to conduct a simultaneous investigation using the same mouse model under the same experimental conditions. C57BL/6J mice were divided into five groups: normal chow (NC), high-fat diet (HFD), HFD + 3% bofutsushosan extract (BTS), HFD + 3% boiogito extract (BOT), and HFD + 3% daisaikoto extract (DST). Epididymal white adipose tissue (WAT) weight, mesenteric WAT weight, serum triglyceride levels, and serum total cholesterol levels were measured. Additionally, total bacteria, alpha diversity, beta diversity, and bacterial composition in stool samples were measured. Body weight and epididymal WAT weight gain were significantly inhibited in the BTS-treated group and DST-treated group, but not in the BOT-treated group, compared with the HFD control group. Additionally, serum total cholesterol levels were significantly lower in the DST-treated group than in the HFD group. Specific intestinal bacteria, Clostridium sensu stricto 1, Erysipelatoclostridium, Roseburia, and the Lachnospiraceae NK4A136 group, were significantly changed in the Kampo-treated groups compared with the HFD group, and each of them was correlated with body weight gain, body fat rate, epididymal WAT weight, or mesenteric WAT weight. Our simultaneous investigation of BTS, BOT, and DST under the same conditions clearly demonstrated different changes in the intestinal microbiota and different effects on fat accumulation as well as their association among the three Kampo medicines.