MicroRNAs in metabolism and metabolic disorders

Abstract

MicroRNAs (miRNAs) such as miR-33a and miR-33b are key regulators of cholesterol and lipid homeostasis and represent attractive therapeutic targets for raising high-density lipoprotein (HDL) levels and lowering triglyceride levels. A role has recently been elucidated for miRNAs (for example, miR-103, miR-107 and let-7) in regulation of insulin signalling and control of glucose homeostasis. An emerging link of certain miRNAs to metabolic dysregulation in adipogenesis and obesity suggests that this class of non-coding RNAs may have important roles in disorders associated with metabolic syndrome (MetS). Aberrant hepatic miRNA expression may also contribute to other aspects of MetS, such as non-alcoholic fatty liver disease (NAFLD). Circulating miRNAs have recently been identified in the blood, including as part of HDL. Data suggest that circulating miRNAs may exert effects on gene expression in target cells and tissues. The link of abnormal miRNA expression to metabolic disorders has highlighted the therapeutic potential of antisense targeting of specific miRNAs (for example, miR-122, miR-33a and miR-33b).