Dietary Alaska pollock protein attenuates liver steatosis and alters gut microbiota in leptin-deficient ob/ob mice

Abstract

• Alaska pollock protein attenuated liver steatosis in leptin-deficient ob/ob mice. • Alaska pollock protein activated liver fatty acid oxidation through PPARα pathway. • Alaska pollock protein enhanced acetic acid production in cecal contents. • Alaska pollock protein improved the structure of the microbiota in cecal content. This study examined the effects of dietary Alaska pollock ( Theragra chalcogramma ) protein (APP) on nonalcoholic fatty liver disease (NAFLD) and gut microbiota in leptin-deficient ob/ob mice. Mice were fed with high-fat diet containing either casein or APP for six weeks. Then, lipid accumulation and mRNA expression levels in the liver and the composition and metabolites of the gut microbiota were evaluated. Dietary APP attenuated liver steatosis in part through the enhancement and suppression of gene expression involved in liver fatty acid oxidation and synthesis, respectively. The enhancement of liver peroxisome proliferator-activated receptor alpha mRNA expression level by APP consumption may be partly due to the high acetic acid content in cecal contents. Moreover, APP consumption modified the structure of the microbiota and high relative abundance of probiotic bacteria and low relative abundances of Bacteroides and Blautia in cecal content. Therefore, APP consumption could help prevent NAFLD development.