Obesity-induced upregulation of microRNA-183-5p promotes hepatic triglyceride accumulation by targeting the B-cell translocation gene 1.

Abstract

AIMS\nObesity is recognized as a risk factor for many metabolic disorders, particularly nonalcoholic fatty liver disease (NAFLD). However, the underlying mechanism is still poorly understood. Several lines of evidence indicate that microRNA (miRNA) is a key regulator of lipid metabolism. In this study, we investigated the role of miR-183-5p in the development of NAFLD.\n\n\nMETHODS\nThe expression levels of miR-183-5p and B-cell translocation gene 1 (Btg1) were determined by quantitative real-time PCR and histological analysis in livers of obese mice and cell models induced with palmitic acid (PA), respectively. AML12 cells were treated with PA in the presence or absence of miR-183-5p mimics or inhibitor. Moreover, a Luciferase reporter assay was used to determine whether Btg1 is the direct target of miR-183-5p. Protein levels of BTG1 were estimated using western blotting.\n\n\nKEY FINDINGS\nExpression of miR-183-5p was increased in the livers of three murine models and also in the AML12 cell model. Overexpression of miR-183-5p in the cell model and mice led to hepatic triglyceride (TG) accumulation and upregulation of lipogenic genes, whereas inhibition of miR-183-5p in the cell model improved hepatic TG accumulation. Mechanistically, we further identified Btg1 as a direct target gene of miR-183-5p.\n\n\nSIGNIFICANCE\nOur findings revealed that miR-183-5p affected the regulation of hepatic TG homeostasis, which may provide a potential therapeutic target for hepatosteatosis.