title: MicroRNAs in metabolism.
abstract: MicroRNAs (miRNAs) have within the past decade emerged as key regulators of metabolic homoeostasis. Major tissues in intermediary metabolism important during development of the metabolic syndrome, such as β-cells, liver, skeletal and heart muscle as well as adipose tissue, have all been shown to be affected by miRNAs. In the pancreatic β-cell, a number of miRNAs are important in maintaining the balance between differentiation and proliferation (miR-200 and miR-29 families) and insulin exocytosis in the differentiated state is controlled by miR-7, miR-375 and miR-335. MiR-33a and MiR-33b play crucial roles in cholesterol and lipid metabolism, whereas miR-103 and miR-107 regulates hepatic insulin sensitivity. In muscle tissue, a defined number of miRNAs (miR-1, miR-133, miR-206) control myofibre type switch and induce myogenic differentiation programmes. Similarly, in adipose tissue, a defined number of miRNAs control white to brown adipocyte conversion or differentiation (miR-365, miR-133, miR-455). The discovery of circulating miRNAs in exosomes emphasizes their importance as both endocrine signalling molecules and potentially disease markers. Their dysregulation in metabolic diseases, such as obesity, type 2 diabetes and atherosclerosis stresses their potential as therapeutic targets. This review emphasizes current ideas and controversies within miRNA research in metabolism.
authors.affiliation: Center for Basic Metabolic Research, Faculty of Health, University of Copenhagen, Copenhagen, Denmark.
authors.forename: S
authors.initials: S
authors.lastname: Vienberg
authors.affiliation: Department of Science and Environment, Roskilde University, Roskilde, Denmark.
authors.forename: J
authors.initials: J
authors.lastname: Geiger
authors.affiliation: Center for Basic Metabolic Research, Faculty of Health, University of Copenhagen, Copenhagen, Denmark.
authors.forename: S
authors.initials: S
authors.lastname: Madsen
authors.affiliation: Department of Science and Environment, Roskilde University, Roskilde, Denmark.
authors.forename: L T
authors.identifier: 0000-0002-3598-2775
authors.initials: LT
authors.lastname: Dalgaard
mesh_terms: D000818:Animals; D006706:Homeostasis / Q000502:physiology*; D006801:Humans; D008660:Metabolism / Q000235:genetics*; D035683:MicroRNAs / Q000502:physiology*
chemical_list: D035683:MicroRNAs
keywords: adipocytes; metabolism; microRNA; non-alcoholic hepato-steatosis; type 2 diabetes mellitus; β-cells