title: PGC-1α is required for exercise- and exercise training-induced UCP1 up-regulation in mouse white adipose tissue.
abstract: BACKGROUND
  The aim of the present study was to test the hypotheses that 1) a single exercise bout increases UCP1 mRNA in both inguinal (i)WAT and epididymal (e)WAT, 2) UCP1 expression and responsiveness to exercise are different in iWAT and eWAT, 3) PGC-1α determines the basal levels of UCP1 and PRDM16 in WAT and 4) exercise and exercise training regulate UCP1 and PRDM16 expression in WAT in a PGC-1α-dependent manner.
  
  
  METHODS
  Whole body PGC-1α knockout (KO) and wildtype (WT) littermate mice performed a single treadmill exercise bout at 14 m/min and 10% slope for 1 hour. Mice were sacrificed and iWAT, eWAT and quadriceps muscle were removed immediately after, 2, 6 and 10 hours after running, and from sedentary mice that served as controls. In addition, PGC-1α KO mice and WT littermates were exercise trained for 5 weeks with sedentary mice as untrained controls. Thirty-six-37 hours after the last exercise bout iWAT was removed.
  
  
  RESULTS
  UCP1 mRNA content increased 19-fold in iWAT and 7.5-fold in eWAT peaking at 6 h and 0' of recovery, respectively, in WT but with no changes in PGC-1α KO mice. UCP1 protein was undetectable in eWAT and very low in iWAT of untrained mice but increased with exercise training to 4.4 (AU) in iWAT from WT mice without significant effects in PGC-1α KO mice.
  
  
  CONCLUSIONS
  The present observations provide evidence that exercise training increases UCP1 protein in iWAT through PGC-1α, likely as a cumulative effect of transient increases in UCP1 expression after each exercise bout. Moreover, the results suggest that iWAT is more responsive than eWAT in exercise-induced regulation of UCP1. In addition, as PRDM16 mRNA content decreased in recovery from acute exercise, the present findings suggest that acute exercise elicits regulation of several brown adipose tissue genes in mouse WAT.
authors.affiliation: Department of Biology, Centre of Inflammation and Metabolism and August Krogh Centre, University of Copenhagen, Copenhagen, Denmark.
authors.forename: Stine
authors.initials: S
authors.lastname: Ringholm
authors.forename: Jakob
authors.initials: J
authors.lastname: Grunnet Knudsen
authors.forename: Lotte
authors.initials: L
authors.lastname: Leick
authors.forename: Anders
authors.initials: A
authors.lastname: Lundgaard
authors.forename: Maja
authors.initials: M
authors.lastname: Munk Nielsen
authors.forename: Henriette
authors.initials: H
authors.lastname: Pilegaard
mesh_terms: D052436:Adipose Tissue, White / Q000378:metabolism*; D000818:Animals; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D006003:Glycogen / Q000235:genetics / Q000378:metabolism; D007473:Ion Channels / Q000235:genetics* / Q000378:metabolism*; D008297:Male; D051379:Mice; D018345:Mice, Knockout; D024101:Mitochondrial Proteins / Q000235:genetics* / Q000378:metabolism*; D000071248:Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha; D010805:Physical Conditioning, Animal; D019408:Platelet Endothelial Cell Adhesion Molecule-1 / Q000235:genetics / Q000378:metabolism; D052097:Quadriceps Muscle / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics; D014157:Transcription Factors / Q000235:genetics* / Q000378:metabolism*; D000071256:Uncoupling Protein 1; D015854:Up-Regulation / Q000235:genetics*
chemical_list: D004268:DNA-Binding Proteins; D007473:Ion Channels; D024101:Mitochondrial Proteins; D000071248:Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha; D019408:Platelet Endothelial Cell Adhesion Molecule-1; C485290:Ppargc1a protein, mouse; C521133:Prdm16 protein, mouse; D012333:RNA, Messenger; D014157:Transcription Factors; C000604372:Ucp1 protein, mouse; D000071256:Uncoupling Protein 1; D006003:Glycogen