Hydrogen alleviates non-alcoholic fatty liver disease in mice by regulating intestinal flora

Abstract

Despite being the most common form of chronic liver disease, there are still no approved drugs for thetreatment of non-alcoholic fatty liver disease (NAFLD). The aim of this study was to elucidate the therapeutic effects and possible mechanisms of hydrogen (H2) inhalation in mice with NAFLD. Male C57BL/6 mice (6 weeks old) were fed either a 60% fat diet (high-fat diet [HFD]) or a 10% fat diet (normal diet) for 11 weeks. Then, H2 was administered to random HFD-fed mice for another 11 weeks before they were euthanized. Biochemical analysis of serum samples, histological analysis of liver and ileum samples, 16S rRNA sequencing analysis of stool samples, and analysis of the expression levels of related factors by enzyme-linked immunosorbent assay were conducted to determine the effect of H2 intervention on NAFLD. H2 inhalation alleviated hyperglycemia and impaired glucose tolerance; decreased the serum concentrations of triglycerides, cholesterol, alanine aminotransferase, aspartate aminotransferase, lipopolysaccharide, and tumor necrosis factor-alpha; and ameliorated liver injury by a HFD, although no weight loss was observed. Interestingly, H2 inhalation increased the relative abundance of Akkermansia muciniphila and decreased the Firmicutes-to-Bacteroidia ratio in the intestinal tract of NAFLD mice. These data indicate that H2 alleviated the symptoms of NAFLD by increasing the abundance of A. muciniphila in the intestine. Thus, H2 may be a new potential treatment strategy for patients with NAFLD.