Methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism associated with body fat accumulation could possibly trigger an inflammatory process by elevating homocysteine levels and increasing cytokine production, causing several diseases. This study aimed to evaluate the effects of food intervention, and not folate supplements, on the levels of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and interleukin-1β (IL-1β) in overweight and obese women with the MTHFR C677T polymorphism. A randomized, double-blind eight-week clinical trial of 48 overweight and obese women was conducted. Participants were randomly assigned into two groups. They received 300 g of vegetables daily for eight weeks containing different doses of folate: 95 µg/day for Group 1 and 191 µg/day for Group 2. MTHFR C677T polymorphism genotyping was assessed by digestion with HinfI enzyme and on 12% polyacrylamide gels. Anthropometric measurements, 24-h dietary recall, and biochemical analysis (blood folic acid, vitamin B12, homocysteine (Hcy), TNF-α, IL-1β, and IL-6) were determined at the beginning and end of the study. Group 2 had a significant increase in folate intake (p < 0.001) and plasma folic acid (p < 0.05) for individuals with the cytosine–cytosine (CC), cytosine–thymine (CT), and thymine–thymine (TT) genotypes. However, only individuals with the TT genotype presented reduced levels of Hcy, TNF-α, IL-6, and IL-1β (p < 0.001). Group 1 showed significant differences in folate consumption (p < 0.001) and folic acid levels (p < 0.05) for individuals with the CT and TT genotypes. Food intervention with folate from vegetables increased folic acid levels and reduced interleukins, TNF-α, and Hcy levels, mainly for individuals with the TT genotype.

BackgroundDNA methylation has been evidenced as a potential epigenetic mechanism related to various candidate genes to development of obesity. Therefore, the objective of this study was to evaluate the DNA methylation levels of the ADRB3 gene by body mass index (BMI) in a representative adult population, besides characterizing this population as to the lipid profile, oxidative stress and food intake.MethodsThis was a cross-sectional population-based study, involving 262 adults aged 20–59 years, of both genders, representative of the East and West regions of the municipality of João Pessoa, Paraíba state, Brazil, in that were evaluated lifestyle variables and performed nutritional, biochemical evaluation and DNA methylation levels of the ADRB3 gene using high resolution melting method. The relationship between the study variables was performed using analyses of variance and multiple regression models. All results were obtained using the software R, 3.3.2.ResultsFrom the stratification of categories BMI, was observed a difference in the average variables values of age, waist-to-height ratio, waist-to-hip ratio, waist circumference, triglycerides and intake of trans fat, which occurred more frequently between the categories “eutrophic” and “obesity”. From the multiple regression analysis in the group of eutrophic adults, it was observed a negative relationship between methylation levels of the ADRB3 gene with serum levels of folic acid. However, no significant relation was observed among lipid profile, oxidative stress and food intake in individuals distributed in the three categories of BMI.ConclusionsA negative relationship was demonstrated between methylation levels of the ADRB3 gene in eutrophic adults individuals with serum levels of folic acid, as well as with the independent gender of BMI, however, was not observed relation with lipid profile, oxidative stress and variables of food intake. Regarding the absence of relationship with methylation levels of the ADRB3 gene in the categories of overweight, mild and moderate obesity, the answer probably lies in the insufficient amount of body fat to initiate inflammatory processes and oxidative stress with a direct impact on methylation levels, what is differently is found most of the times in exacerbated levels in severe obesity.Electronic supplementary materialThe online version of this article (10.1186/s12967-018-1529-0) contains supplementary material, which is available to authorized users.

Background Defects in DNA methylation have been shown to be associated with metabolic diseases such as obesity, dyslipidemia, and hypercholesterolemia. To analyze the methylation profile of the ADRB3 gene and correlate it with lipid profile, lipid intake, and oxidative stress based on malondialdehyde (MDA) and total antioxidant capacity (TAC), homocysteine and folic acid levels, nutritional status, lifestyle, and socioeconomic variables in an adult population. A cross-sectional epidemiological study representative of the East and West regions of the municipality of João Pessoa, Paraíba state, Brazil, enrolled 265 adults of both genders. Demographic, lifestyle, and socioeconomic questionnaires and a 24-h recall questionnaire were applied by trained interviewers’ home. Nutritional and biochemical evaluation (DNA methylation, lipid profile, MDA, TAC, homocysteine and folic acid levels) was performed. Results DNA hypermethylation of the ADRB3 gene, analyzed in leukocytes, was present in 50% of subjects and was associated with a higher risk of being overweight (OR 3.28; p = 0.008) or obese (OR 3.06; p = 0.017), a higher waist–hip ratio in males (OR 1.17; p = 0.000), greater intake of trans fats (OR 1.94; p = 0.032), higher LDL (OR 2.64; p = 0.003) and triglycerides (OR 1.81; p = 0.031), and higher folic acid levels (OR 1.85; p = 0.022). Conclusions These results suggest that epigenetic changes in the ADRB3 gene locus may explain the development of obesity and non-communicable diseases associated with trans-fat intake, altered lipid profile, and elevated folic acid. Because of its persistence, DNA methylation may have an impact in adults, in association with the development of non-communicable diseases. This study is the first population-based study of the ADRB3 gene, and the data further support evaluation of ADRB3 DNA methylation as an effective biomarker.

Obesity is highly prevalent in developed countries and contributes to a substantial burden of morbidity and mortality. Increased adiposity is often accompanied by comorbidities such as insulin resistance, type 2 diabetes, hypercholesterolemia, cardiovascular disease, fatty liver disease, low-grade inflammation, immune disorders, endocrine complications, and sleep apnea, which may require specific dietary and pharmacological interventions. The current obesity epidemic requires a better understanding of the underlying mechanisms through which genetic and epigenetic factors interact to determine metabolic characteristics. Epigenetic studies are dynamic; tags with reversible potential can be influenced by genetics and environment attributing phenotypic variations. There are large knowledge gaps regarding how human epigenetic changes are related to obesity and its consequences. Therefore, the present study elucidates the role of epigenetics in the etiology of obesity. Recent studies suggest that the epigenetic regulation of gene expression (DNA methylation and histone modifications) could be a major contributor to the variation of susceptibility to diseases such as obesity. The identification of genes that determine obesity susceptibility can provide information on the pathophysiological mechanisms underlying body weight regulation, food intake control and fat distribution, which in turn can lead to new approaches to treatment and prevention of obesity.

Introduction:The aim of the present study was to evaluate the amount and quality of fat consumed habitually by pre-diabetic and normoglycaemic adults. Materials and Methods:A cross-sectional epidemiological study involving 233 individuals from the East and West Zones of the municipality of João Pessoa, Northeastern Brazil, was performed. Anthropometric, biochemical, food consumption, and lifestyle data were collected.Results: There were no differences for demographic, socioeconomic, epidemiological variables, as well as for the variables of habitual consumption of fat and different types of isolated or associated fatty acids and lifestyle between the two groups. However, different relationships were observed in each group, between fasting blood glucose values and fat consumption, such as: in the pre-diabetic group there was an inverse relationship with fat consumption tertiles in relation to fatty acids (AG) monounsaturated (M) -(15.16 ± 0.65g and 24.11 ± 2.74g) and Index I: S (I: S) -(1.39 ± 0.72g); and positive relationships with the consumption of the w-6: w-3 and w-6: w-9 indexes. In the normoglycemic group, inverse relationships were observed with the consumption of AGM w-3 and the w-3 total fat index and a positive relationship with the consumption of total polyunsaturated AG fats, indexes w-6: w-3, I: S w-6: w-9. Conclusion:It was concluded that there were no differences between the consumption variables for all types of fats between the two groups, but differences were observed in terms of the amounts consumed, especially regarding the indices between fatty acids, when relating these values of consumption in each group with fasting blood glucose values. Therefore, the quantitative needs of different types of fats to prevent the increase or reduction of blood glucose, are possibly different between normoglycemic and pre-diabetic.