title: ERRγ enhances UCP1 expression and fatty acid oxidation in brown adipocytes.
abstract: OBJECTIVE
  Estrogen-related receptors (ERRs) are important regulators of energy metabolism. Here we investigated the hypothesis that ERRγ impacts on differentiation and function of brown adipocytes.
  
  
  METHODS
  We characterize the expression of ERRγ in adipose tissues and cell models and investigate the effects of modulating ERRγ activity on UCP1 gene expression and metabolic features of brown and white adipocytes.
  
  
  RESULTS
  ERRγ was preferentially expressed in brown compared to white fat depots, and ERRγ was induced during cold-induced browning of subcutaneous white adipose tissue and brown adipogenesis. Overexpression of ERRγ positively regulated uncoupling protein 1 (UCP1) expression levels during brown adipogenesis. This ERRγ-induced augmentation of UCP1 expression was independent of the presence of peroxisome proliferator-activated receptor coactivator-1 (PGC-1α) but was associated with increased rates of fatty acid oxidation in adrenergically stimulated cells. ERRγ did not influence mitochondrial biogenesis, and its reduced expression in white adipocytes could not explain their low expression level of UCP1.
  
  
  CONCLUSIONS
  Through its augmenting effect on expression of UCP1, ERRγ may physiologically be involved in increasing the potential for energy expenditure in brown adipocytes, a function that is becoming of therapeutic interest.
authors: Department of Biomedical Sciences, University of Copenhagen, DK-2200 Copenhagen N, Denmark.
authors: Karen
authors: K
authors: Dixen
authors: Astrid L
authors: AL
authors: Basse
authors: Maria
authors: M
authors: Murholm
authors: Marie S
authors: MS
authors: Isidor
authors: Lillian H L
authors: LH
authors: Hansen
authors: M Christine H
authors: MC
authors: Petersen
authors: Lise
authors: L
authors: Madsen
authors: Natasa
authors: N
authors: Petrovic
authors: Jan
authors: J
authors: Nedergaard
authors: Bjørn
authors: B
authors: Quistorff
authors: Jacob B
authors: JB
authors: Hansen
mesh_terms: D052437:Adipocytes, Brown / Q000378:metabolism*; D052438:Adipocytes, White / Q000378:metabolism; D050156:Adipogenesis; D052436:Adipose Tissue, White / Q000378:metabolism; D000818:Animals; D002454:Cell Differentiation; D002478:Cells, Cultured; D056915:DNA Copy Number Variations; D004272:DNA, Mitochondrial / Q000235:genetics / Q000302:isolation & purification; D004734:Energy Metabolism; D005260:Female; D007473:Ion Channels / Q000235:genetics / Q000378:metabolism*; D007770:L-Lactate Dehydrogenase / Q000235:genetics / Q000378:metabolism; D050356:Lipid Metabolism; D008066:Lipolysis / Q000502:physiology; D051379:Mice; D008810:Mice, Inbred C57BL; D024101:Mitochondrial Proteins / Q000235:genetics / Q000378:metabolism*; D010084:Oxidation-Reduction; D010172:Palmitoylcarnitine / Q000378:metabolism; D000071248:Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D011960:Receptors, Estrogen / Q000235:genetics / Q000378:metabolism*; D015534:Trans-Activators / Q000235:genetics / Q000378:metabolism; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism; D000071256:Uncoupling Protein 1
chemical_list: D004272:DNA, Mitochondrial; D007473:Ion Channels; D024101:Mitochondrial Proteins; D000071248:Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha; C485290:Ppargc1a protein, mouse; C501429:Ppargc1a protein, rat; D012333:RNA, Messenger; D011960:Receptors, Estrogen; D015534:Trans-Activators; D014157:Transcription Factors; C000604372:Ucp1 protein, mouse; C000604373:Ucp1 protein, rat; D000071256:Uncoupling Protein 1; D010172:Palmitoylcarnitine; D007770:L-Lactate Dehydrogenase