Ishige okamurae Celluclast extract ameliorates non-alcoholic fatty liver in high-fructose diet-fed mice by modulation of lipid metabolism and gut microbiota composition.

Recently, a new mechanism has revealed that gut microbiota plays a pivotal role in metabolizing fructose to acetate that facilitates hepatic lipogenesis. Therefore, our study investigated the role of microbiome on abnormal lipid synthesis in the presence of fructose and identified attenuating effects of Ishige okamurae Celluclast extract (IOCE) against fructose-induced fatty liver. The results indicated that oral administration of IOCE (150 and 300 mg/kg/day for 12 weeks) significantly reduced both gut microbiota-mediated and -non-mediated hepatic lipogenesis simultaneously triggered by fructose metabolism. IOCE reduced hepatic triglyceride accumulation and expression levels of key enzymes for glucolipid metabolism. In addition, IOCE regulated fatty acid synthesis, β-oxidation, and improved hepatic inflammation. Furthermore, IOCE inhibited direct fructose-to-acetate conversion and altered the compositions of gut microbiota. These findings suggest that IOCE might serve as a potential prebiotic dietary supplement by ameliorating fatty liver through dual regulation of classical lipogenic pathway and gut microbiota.