title: DNA methylation pattern in overweight women under an energy-restricted diet supplemented with fish oil.
abstract: Dietary factors modulate gene expression and are able to alter epigenetic signatures in peripheral blood mononuclear cells (PBMC). However, there are limited studies about the effects of omega-3 polyunsaturated fatty acids (n-3 PUFA) on the epigenetic mechanisms that regulate gene expression. This research investigates the effects of n-3-rich fish oil supplementation on DNA methylation profile of several genes whose expression has been reported to be downregulated by n-3 PUFA in PBMC: CD36, FFAR3, CD14, PDK4, and FADS1. Young overweight women were supplemented with fish oil or control in a randomized 8-week intervention trial following a balanced diet with 30% energy restriction. Fatty acid receptor CD36 decreased DNA methylation at CpG +477 due to energy restriction. Hypocaloric diet-induced weight loss also reduced the methylation percentages of CpG sites located in CD14, PDK4, and FADS1. The methylation patterns of these genes were only slightly affected by the fish oil supplementation, being the most relevant to the attenuation of the weight loss-induced decrease in CD36 methylation after adjusting by baseline body weight. These results suggest that the n-3 PUFA-induced changes in the expression of these genes in PBMC are not mediated by DNA methylation, although other epigenetic mechanisms cannot be discarded.
authors.affiliation: Department of Nutrition, Food Sciences and Physiology, University of Navarra, C/Irunlarrea 1, 31008 Pamplona, Spain ; Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, Avenue Professor Lineu Prestes, 1524, 05508-900 São Paulo, SP, Brazil.
authors.forename: Cátia Lira
authors.initials: CL
authors.lastname: do Amaral
authors.affiliation: Department of Nutrition, Food Sciences and Physiology, University of Navarra, C/Irunlarrea 1, 31008 Pamplona, Spain ; CIBER Fisiopatología de la Obesidad y la Nutrición (CIBERobn), Instituto de Salud Carlos III, 28029 Madrid, Spain.
authors.forename: Fermín I
authors.initials: FI
authors.lastname: Milagro
authors.affiliation: Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, Avenue Professor Lineu Prestes, 1524, 05508-900 São Paulo, SP, Brazil.
authors.forename: Rui
authors.initials: R
authors.lastname: Curi
authors.affiliation: Department of Nutrition, Food Sciences and Physiology, University of Navarra, C/Irunlarrea 1, 31008 Pamplona, Spain ; CIBER Fisiopatología de la Obesidad y la Nutrición (CIBERobn), Instituto de Salud Carlos III, 28029 Madrid, Spain.
authors.forename: J Alfredo
authors.initials: JA
authors.lastname: Martínez
mesh_terms: D000328:Adult; D000818:Animals; D031204:Caloric Restriction; D019175:DNA Methylation / Q000187:drug effects*; D000090943:Delta-5 Fatty Acid Desaturase; D019587:Dietary Supplements; D015525:Fatty Acids, Omega-3 / Q000008:administration & dosage*; D005260:Female; D005395:Fish Oils / Q000008:administration & dosage*; D005786:Gene Expression Regulation / Q000187:drug effects; D006801:Humans; D007963:Leukocytes, Mononuclear / Q000378:metabolism*; D050177:Overweight / Q000178:diet therapy / Q000235:genetics / Q000473:pathology
chemical_list: D000090943:Delta-5 Fatty Acid Desaturase; D015525:Fatty Acids, Omega-3; D005395:Fish Oils; C000716847:FADS1 protein, human