title: Weight regain after slimming induced by an energy-restricted diet depends on interleukin-6 and peroxisome-proliferator-activated-receptor-gamma2 gene polymorphisms.
abstract: Weight-loss maintenance after following an energy-restricted diet is a major problem that a number of studies are trying to characterise. The aim of the present study was to investigate the role of IL-6 -174G>C and PPAR-gamma2 Pro12Ala variants on weight regulation in obese subjects receiving a low-energy diet and at 1 year after the acute slimming period. Sixty-seven volunteers (age 34.7 (SD 7.0) years; BMI 35.8 (SD 4.8) kg/m(2)) were enrolled in a 10-week dietary intervention and were contacted again 1 year after the end of this period. Body composition was measured at three times during the study. Also, PPAR-gamma2 Pro12Ala and IL-6 -174G>C polymorphisms were analysed in the participants. No statistical differences were observed depending on the genetic variants at baseline for anthropometric variables, or after the intervention. However, the C allele of the -174G>C IL-6 gene polymorphism was more frequently observed (P=0.032) in subjects with successful weight maintenance (<10 % weight regain). In fact, the C allele partially protected against weight regain (odds ratio 0.24; P=0.049), while the conjoint presence of both gene variants (C+ and Ala+) further improved the ability for weight maintenance (odds ratio 0.19; P=0.043). The present study demonstrates that the C allele of the -174G>C polymorphism gives protection against regain of weight lost. Moreover, the presence of the Ala allele of the PPARgamma-2 together with the C allele strengthens this protection. These findings support a role for these polymorphisms on weight regulation and suggest a synergetic effect of both variants on weight maintenance after following a diet to lose weight.
authors.affiliation: Department of Physiology and Nutrition, University of Navarra, Irunlarrea 1, 31008 Pamplona, Spain.
authors.forename: Estibaliz
authors.initials: E
authors.lastname: Goyenechea
authors.forename: M
authors.initials: M
authors.lastname: Dolores Parra
authors.forename: J
authors.initials: J
authors.lastname: Alfredo Martínez
mesh_terms: D000328:Adult; D000483:Alleles; D015415:Biomarkers / Q000032:analysis; D001823:Body Composition / Q000235:genetics; D002097:C-Reactive Protein / Q000032:analysis; D031204:Caloric Restriction / Q000379:methods*; D005260:Female; D005787:Gene Frequency / Q000235:genetics; D005838:Genotype; D006801:Humans; D015850:Interleukin-6 / Q000097:blood / Q000235:genetics*; D020738:Leptin / Q000097:blood; D008297:Male; D009765:Obesity / Q000188:drug therapy* / Q000235:genetics; D047495:PPAR gamma / Q000235:genetics*; D011110:Polymorphism, Genetic / Q000235:genetics*; D015430:Weight Gain / Q000235:genetics*; D015431:Weight Loss
chemical_list: D015415:Biomarkers; D015850:Interleukin-6; D020738:Leptin; D047495:PPAR gamma; D002097:C-Reactive Protein