title: DNA Methylation Changes Induced by a High-Fat Diet and Fish Oil Supplementation in the Skeletal Muscle of Mice.
abstract: OBJECTIVE
  To investigate the global changes in DNA methylation and methylation of the promoter region of the peroxisome proliferator-activated receptor gamma transcript variant 2 (Pparg2) gene resulting from a high-fat diet (HFD) and/or fish oil supplementation.
  
  
  METHODS
  Fish oil, rich in omega-3 polyunsaturated fatty acids, or water was orally administered to male mice for 12 weeks. After the first 4 weeks, the animals were fed a control diet or an HFD until the end of the experimental protocol, when the epididymal fat, gastrocnemius muscle and liver were excised.
  
  
  RESULTS
  Pparg2 mRNA expression was upregulated by obesity and downregulated by fish oil supplementation in the liver. In the gastrocnemius muscle, diet-induced obesity increased global DNA methylation. Fish oil prevented the decrease in Pparg2 promoter methylation induced by obesity in the gastrocnemius muscle. Regardless of the diet given, fish oil supplementation increased Pparg2 promoter methylation at CpG-263 in muscle and adipose tissue.
  
  
  CONCLUSIONS
  HFD and fish oil modified global and Pparg2 promoter DNA methylation in a tissue-specific manner. Fish oil supplementation attenuated body weight gain, abolished the increase in Pparg2 expression in the liver and prevented the decrease in Pparg2 promoter methylation in the muscle induced by the HFD.
authors.affiliation: Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil.
authors.forename: Catia L
authors.initials: CL
authors.lastname: Amaral
authors.forename: Amanda R
authors.initials: AR
authors.lastname: Crisma
authors.forename: Laureane N
authors.initials: LN
authors.lastname: Masi
authors.forename: Amanda R
authors.initials: AR
authors.lastname: Martins
authors.forename: Sandro M
authors.initials: SM
authors.lastname: Hirabara
authors.forename: Rui
authors.initials: R
authors.lastname: Curi
mesh_terms: D000273:Adipose Tissue / Q000378:metabolism; D000818:Animals; D019175:DNA Methylation; D059305:Diet, High-Fat / Q000009:adverse effects*; D019587:Dietary Supplements; D015525:Fatty Acids, Omega-3 / Q000008:administration & dosage; D005395:Fish Oils / Q000008:administration & dosage*; D008099:Liver / Q000378:metabolism; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D018482:Muscle, Skeletal / Q000378:metabolism*; D054647:Nutrigenomics; D009765:Obesity / Q000178:diet therapy / Q000235:genetics / Q000378:metabolism; D047495:PPAR gamma / Q000235:genetics; D011401:Promoter Regions, Genetic; D014018:Tissue Distribution
chemical_list: D015525:Fatty Acids, Omega-3; D005395:Fish Oils; D047495:PPAR gamma