Gut microbiota composition associated with hepatic fibrosis in non‐obese patients with non‐alcoholic fatty liver disease
Michihiro Iwaki, Takaomi Kessoku, Anna Ozaki, Yuki Kasai, Takashi Kobayashi, Asako Nogami, Yasushi Honda, Yuji Ogawa, Kento Imajo, Masato Yoneda, Ayako Maeda, Yoshiki Tanaka, Shunji Nakajima, Hiroshi Ohno, Haruki Usuda, Miwa Kawanaka, Takumi Kawaguchi, Takuji Torimura, Masayoshi Kage, Hideyuki Hyogo, Hirokazu Takahashi, Yuichiro Eguchi, Shinichi Aishima, Koichiro Wada, Noritoshi Kobayashi, Yoshio Sumida, Satoru Saito, Atsushi Nakajima
Abstract
Abstract Background and Aim Gut microbiota composition is associated with the pathogenesis of non‐alcoholic fatty liver disease. However, the association between gut microbiota composition and non‐alcoholic fatty liver disease in non‐obese patients remains unclear. We compared clinical parameters and gut microbiota profiles of healthy controls and non‐obese and obese patients with non‐alcoholic fatty liver disease. Methods We examined the clinical parameters and gut microbiota profiles by 16S rRNA sequences and short‐chain fatty acid levels in fecal samples from 51 non‐obese patients with non‐alcoholic fatty liver disease (body mass index <25 kg/m 2 ) and 51 obese patients with non‐alcoholic fatty liver disease (body mass index ≥30 kg/m 2 ) who underwent pathological examination and 87 controls at five hospitals in Japan. Results Although no significant differences between the non‐obese and other groups were observed in alpha diversity, a significant difference was found in beta diversity. We observed a significant decrease in serum alanine aminotransferase levels, Eubacterium population, and butyric acid levels in non‐obese patients with non‐alcoholic fatty liver disease compared with those in obese patients with non‐alcoholic fatty liver disease. A significant negative correlation was found between the stage of hepatic fibrosis and Eubacterium abundance in non‐obese patients with non‐alcoholic fatty liver disease. Conclusions The decrease in the abundance of Eubacterium that produces butyric acid may play an important role in the development of non‐alcoholic fatty liver disease in non‐obese individuals. This study was registered at the University Hospital Medical Information Network clinical trial registration system (UMIN000020917).