title: MicroRNAs in lipid metabolism.
abstract: OBJECTIVE
  Although the role for microRNAs (miRNAs) in regulating multiple physiological processes including apoptosis, cell differentiation, and cancer is well established, the importance of these tiny RNAs in regulating lipid metabolism has only recently been uncovered. This review summarizes the evidence for a critical role of miRNAs in regulating lipid metabolism.
  
  
  RESULTS
  Lipid metabolism is tightly regulated at the cellular level. In addition to classic transcriptional regulation of cholesterol metabolism (e.g. by SREBP and LXR), members of a class of noncoding RNAs termed miRNAs have now been identified to be potent post-transcriptional regulators of lipid metabolism genes involved in cholesterol homeostasis and fatty acid oxidation. Several reports have recently shown that miR-33 regulates cholesterol efflux and HDL biogenesis by downregulating the expression of the ABC transporters, ABCA1 and ABCG1. In addition, miR-33 also inhibits the translation of several transcripts encoding proteins involved in fatty acid β-oxidation including CPT1a, CROT, and HADHB, thereby reducing fatty acid degradation. Other miRNAs including miR-122, miR-370, miR-335, and miR-378/378*, miR-27 and miR-125a-5p have been implicated in regulating cholesterol homeostasis, fatty acid metabolism and lipogenesis.
  
  
  CONCLUSIONS
  Recent advances in the understanding of the regulation of lipid metabolism indicate that miRNAs play major roles in regulating cholesterol and fatty acid metabolism. These new findings may open new avenues for the treatment of dyslipidemias.
authors.affiliation: Department of Medicine, New York University School of Medicine, New York, New York, USA. carlos.fernandez-hernando@nyumc.org
authors.forename: Carlos
authors.initials: C
authors.lastname: Fernández-Hernando
authors.forename: Yajaira
authors.initials: Y
authors.lastname: Suárez
authors.forename: Katey J
authors.initials: KJ
authors.lastname: Rayner
authors.forename: Kathryn J
authors.initials: KJ
authors.lastname: Moore
mesh_terms: D000818:Animals; D002784:Cholesterol / Q000378:metabolism; D005227:Fatty Acids / Q000378:metabolism; D006801:Humans; D050356:Lipid Metabolism; D035683:MicroRNAs / Q000235:genetics / Q000378:metabolism*; D051779:Sterol Regulatory Element Binding Proteins / Q000235:genetics / Q000378:metabolism
chemical_list: D005227:Fatty Acids; D035683:MicroRNAs; D051779:Sterol Regulatory Element Binding Proteins; D002784:Cholesterol