Interação entre gene e nutriente e sua associação à obesidade e ao diabetes melito

Relationship Between the Single Nucleotide Polymorphism A35C in the Cu/Zn-Superoxide Dismutase-1 Gene and Glycemic Control in Individuals with Type 2 Diabetes Mellitus

Hyperglycemia in type 2 diabetes mellitus (T2DM) increases oxidative stress. Furthermore, the presence of the single nucleotide polymorphism A35C (SNP A35C) in Cu/Zn-superoxide dismutase1 (SOD1) gene is closely related to this increase in oxidative stress and the development and progression of T2DM and its complications. This study aimed to evaluate the association between SNP A35C (rs2234694) genotypes and glycemic control in T2DM individuals. A total of 110 individuals were evaluated for anthropometric parameters, body composition, glycemic metabolism markers (fasting serum glucose, %HbA1c, insulin, C-peptide, and HOMA-IR, -%B, -%S), and SOD activity. Individuals were grouped according to SNP A35C genotypes. Variables of interest were assessed according to groups. The T-test for independent samples or the Mann-Whitney U test was used to analyze the differences in continuous variables between groups, and the chi-square test was performed for categorical variables. A binary logistic regression model was constructed, with p < 0.05 considered significant. Overweight was found in 81.8% of individuals with T2DM. Individuals with the AC genotype for SNP A35C had higher levels of fasting serum glucose (p = 0.018) and lower values of HOMA-%B (p = 0.044). The presence of the variant allele was positively associated with higher values of fasting serum glucose (OR: 11.340; 95%IC 1.173-109.649; p = 0.036) and HOMA-IR (OR: 9.987; 95%IC 1.127-88.506; p = 0.039). Individuals with the AC genotype of SNP A35C had poorer glycemic control than individuals with the AA genotype, and the presence of the variant allele was associated with poor glycemic control in T2DM individuals.

Gestational Weight Gain: Is the Role of Genetic Variants a Determinant? A Review

Excessive or insufficient gestational weight gain (GWG) leads to diverse adverse maternal and neonatal outcomes. There is evidence that pregestational body mass index (pBMI) plays a role in GWG, but no genetic cause has been identified. In this review, we aim to analyze genotype variants associated with GWG. Results: We identified seven genotype variants that may be involved in GWG regulation that were analyzed in studies carried out in Brazil, Romania, the USA, Turkey, Ukraine, and Canada. Some genetic variants were only associated with GWG in certain races or depending on the pBMI. In women who were obese or overweight before gestation, some genetic variants were associated with GWG. Environmental and genetic factors together showed a greater association with GWG than genetic factors alone; for example, type of diet was observed to have a significant influence. Conclusions: We found little scientific evidence of an association between genotype variants in countries with a high prevalence of women of reproductive age who are overweight and obese, such as in Latin America. GWG may be more dependent on environmental factors than genetic variants. We suggest a deeper study of genetic variants, cytokines, and their possible association with GWG, always with the respective control of potential cofounding factors, such as pBMI, diet, and race.

FTO and ADRB2 Genetic Polymorphisms Are Risk Factors for Earlier Excessive Gestational Weight Gain in Pregnant Women with Pregestational Diabetes Mellitus: Results of a Randomized Nutrigenetic Trial

Excessive gestational weight gain (GWG) is associated with increased risk of maternal and neonatal complications. We investigated obesity-related polymorphisms in the FTO gene (rs9939609, rs17817449) and ADRB2 (rs1042713, rs1042714) as candidate risk factors concerning excessive GWG in pregnant women with pregestational diabetes. This nutrigenetic trial, conducted in Brazil, randomly assigned 70 pregnant women to one of the groups: traditional diet (n = 41) or DASH diet (n = 29). Excessive GWG was the total weight gain above the upper limit of the recommendation, according to the Institute of Medicine guidelines. Genotyping was performed using real-time PCR. Time-to-event analysis was performed to investigate risk factors for progression to excessive GWG. Regardless the type of diet, AT carriers of rs9939609 (FTO) and AA carriers of rs1042713 (ADRB2) had higher risk of earlier exceeding GWG compared to TT (aHR 2.44; CI 95% 1.03-5.78; p = 0.04) and GG (aHR 3.91; CI 95% 1.12-13.70; p = 0.03) genotypes, respectively, as the AG carriers for FTO haplotype rs9939609:rs17817449 compared to TT carriers (aHR 1.79; CI 95% 1.04-3.06; p = 0.02).

Nutrigenomics in Regulating the Expression of Genes Related to Type 2 Diabetes Mellitus

Nutrigenomics is the study of the gene-nutrient interaction and it indicates that some nutrients, called bioactive compounds, can mold the genetic expression or change the nucleotide chain. Polyphenols are secondary metabolites found in plants that are regularly consumed in functional foods and help prevent or delay the onset of type 2 diabetes mellitus (T2DM) and its complications. This article objected to review studies about the interaction of diet with polyphenols and Mediterranean diet in the expression of human genes related to T2DM. Resveratrol acts as an antioxidant, anti-inflammatory, and increases mitochondrial function. Regular consumption of quercetin resulted in improvement of hypertension and suppression of diabetes-induced vasoconstriction. Genistein also showed positive results in T2DM, such as increased cell mass and improved glucose tolerance and insulin levels. Catechins showed efficiency in inducing genes in triacylglycerol biosynthesis, inhibition of fatty acids and cholesterol, and resulting in their participation in mitigating complications of diabetes. Lastly, curcumin was demonstrated to be a protector of the pancreatic islets against streptozotocin-induced oxidative stress. Growing evidence suggest that bioactive compounds such as polyphenols have an important role in T2DM and the prevention and treatment of its complication, as they cause activation or inhibition of related genes.

Sugar Addiction: From Evolution to Revolution

The obesity epidemic has been widely publicized in the media worldwide. Investigators at all levels have been looking for factors that have contributed to the development of this epidemic. Two major theories have been proposed: (1) sedentary lifestyle and (2) variety and ease of inexpensive palatable foods. In the present review, we analyze how nutrients like sugar that are often used to make foods more appealing could also lead to habituation and even in some cases addiction thereby uniquely contributing to the obesity epidemic. We review the evolutionary aspects of feeding and how they have shaped the human brain to function in "survival mode" signaling to "eat as much as you can while you can." This leads to our present understanding of how the dopaminergic system is involved in reward and its functions in hedonistic rewards, like eating of highly palatable foods, and drug addiction. We also review how other neurotransmitters, like acetylcholine, interact in the satiation processes to counteract the dopamine system. Lastly, we analyze the important question of whether there is sufficient empirical evidence of sugar addiction, discussed within the broader context of food addiction.

Association between polymorphism of tumor necrosis factor alpha (tnfα) in the region -308 g/a with tinnitus in the elderly with a history of occupational noise exposure

Context:

Tinnitus is a common disorder that occurs frequently across all strata of population and has an important health concern and is often associated with different forms of the hearing loss of varying severity.

Aims:

To investigate the association between the polymorphism of tumor necrosis factor alpha (TNFα) in the region −308 G/A with the susceptibility to tinnitus in individuals with the history of exposure to occupational noise.

Settings and Design:

This was a cross-sectional study with a sample of 179 independent elderly people above 60 years of age.

Materials and Methods:

Information on exposure to occupational noise was obtained by interviews. Audiological evaluation was performed using pure tone audiometry and genotyped through polymerase chain reaction by restriction fragment length polymorphism.

Statistical Analysis Used:

Data were analyzed using the chi-square test and the odds ratio (OR), with the significance level set at 5%.

Results:

Among elderly with tinnitus (43.01%), 33.76% had a history of exposure to occupational noise. A statistically significant association was found between genotype frequencies of the TNFα gene in the −308 G/A region and the complaint of tinnitus (P = 0.04 and χ² = 4.19). The elderly with the G allele were less likely to have tinnitus due to occupational noise exposure when compared to those carrying the A allele (OR = 2.74; 95% CI: 1.56–4.81; P < 0.0005).

Conclusion:

This study suggests an association between the TNFα with susceptibility to tinnitus in individuals with a history of exposure to occupational noise.

Guide for Current Nutrigenetic, Nutrigenomic, and Nutriepigenetic Approaches for Precision Nutrition Involving the Prevention and Management of Chronic Diseases Associated with Obesity

Chronic diseases, including obesity, are major causes of morbidity and mortality in most countries. The adverse impacts of obesity and associated comorbidities on health remain a major concern due to the lack of effective interventions for prevention and management. Precision nutrition is an emerging therapeutic approach that takes into account an individual's genetic and epigenetic information, as well as age, gender, or particular physiopathological status. Advances in genomic sciences are contributing to a better understanding of the role of genetic variants and epigenetic signatures as well as gene expression patterns in the development of diverse chronic conditions, and how they may modify therapeutic responses. This knowledge has led to the search for genetic and epigenetic biomarkers to predict the risk of developing chronic diseases and personalizing their prevention and treatment. Additionally, original nutritional interventions based on nutrients and bioactive dietary compounds that can modify epigenetic marks and gene expression have been implemented. Although caution must be exercised, these scientific insights are paving the way for the design of innovative strategies for the control of chronic diseases accompanying obesity. This document provides a number of examples of the huge potential of understanding nutrigenetic, nutrigenomic, and nutriepigenetic roles in precision nutrition.