A common variant near BDNF is associated with dietary calcium intake in adolescents

Association of MC4R rs17782313 Genotype With Energy Intake and Appetite: A Systematic Review and Meta-analysis

CONTEXT

The melanocortin-4 receptor gene (MC4R) is associated with a higher risk of obesity by the presence of the C allele in rs17782313, but the mechanisms are not clear.

OBJECTIVE

The present systematic review and meta-analysis aimed to explore the association between the different genotypes of MC4R rs17782313 and energy intake and appetite.

DATA SOURCES

A literature search was conducted up to June 2023 in PubMed, Scopus, Web of Science, and Cochrane Collaboration databases, following PRISMA guidelines.

DATA EXTRACTION

Inclusion criteria were studies in humans measuring energy intake, appetite, or satiety in all ages and physiological conditions. Studies dealing solely with body mass index were excluded. Twenty-one articles representing 48 560 participants were included in the meta-analysis.

DATA ANALYSIS

According to the NHLBI (National Heart, Lung, and Blood Institute) quality-assessment criteria, all case-control studies and 6 out of 17 cohort and cross-sectional studies were classified as "good," while the rest scored as "fair." Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated in a (CT+CC) vs TT dominant model, and both random-effects and fixed-effects models were used. A statistically significant association between the presence of the C allele and increased appetite was found (OR = 1.25; 95% CI: 1.01-1.49; P = .038) using the fixed-effects model, but the random-effects model proved nonsignificant. However, no association with energy intake was found. None of the variables considered (sample size, year of publication, sex, age group, type of population, origin, and quality) were identified as effect modifiers, and no publication biases were found after subgroup and meta-regression analyses.

CONCLUSION

To our knowledge, this is the first systematic review and meta-analysis that has analyzed the association between rs17782313 of MC4R and energy intake and appetite. Identifying people genetically predisposed to increased appetite may be of great interest, not only to prevent obesity in younger populations but also to avoid malnutrition in elderly persons. This paper is part of the Nutrition Reviews Special Collection on Precision Nutrition.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO registration no. CRD42023417916.

The BDNF Protein is Associated With Glucose Homeostasis and Food Intake in Carriers of Common BDNF Gene Variants

CONTEXT

Brain-derived neurotrophic factor (BDNF) concentrations may differ between BDNF genotype carriers. These changes occur in individuals with metabolic and mental disorders.

OBJECTIVE

The aim of this study was to assess the associations of glucose homeostasis parameters and the frequency of food consumption with BDNF protein concentrations based on BDNF single nucleotide polymorphisms (SNPs).

METHODS

Among the 439 participants, some common rs10835211 BDNF gene variants were analyzed. We evaluated BDNF concentrations, and measured glucose and insulin after fasting and during oral glucose tolerance tests. Anthropometric measurements, body composition, and body fat distribution were assessed, and a 3-day food intake diary and food frequency questionnaire were completed.

RESULTS

We observed significant differences in BDNF concentration between AA and AG genotype rs10835211 carriers (P = .018). The group of AA genotype holders were older, and positive correlation was found between age and BDNF in the whole study population (P = .012) and in the GG genotype carriers (P = .023). Moreover, BDNF protein correlated with fasting insulin (P = .015), HOMA-IR (P = .031), HOMA-B (P = .010), and the visceral/subcutaneous adipose tissue (VAT/SAT) ratio (P = .026) in the GG genotype individuals. Presence of the GG genotype was negatively correlated with nut and seed (P = .047) and lean pork consumption (P = .015), and the BDNF protein. Moreover, we observed correlations between the frequency of chicken (P = .028), pasta (P = .033), and sweet food intake (P = .040) with BDNF concentration in the general population. Among carriers of the AA genotype, we observed a positive correlation between the consumption of rice (P = .048) and sweet food (P = .028) and the BDNF protein level.

CONCLUSION

Peripheral BDNF may be associated with VAT content and insulin concentrations in GG genotype carriers and may vary with particular food intake, which warrants further investigation.

Polymorphisms of Fat Mass and Obesity-Associated Gene in the Pathogenesis of Child and Adolescent Metabolic Syndrome

Childhood metabolic syndrome (MetS) is prevalent around the world and is associated with a high likelihood of suffering from severe diseases such as cardiovascular disease later in adulthood. MetS is associated with genetic susceptibility that involves gene polymorphisms. The fat mass and obesity-associated gene (FTO) encodes an RNA N6-methyladenosine demethylase that regulates RNA stability and molecular functions. Human FTO contains genetic variants that significantly contribute to the early onset of MetS in children and adolescents. Emerging evidence has also uncovered that FTO polymorphisms in intron 1, such as rs9939609 and rs9930506 polymorphisms, are significantly associated with the development of MetS in children and adolescents. Mechanistic studies reported that FTO polymorphisms lead to aberrant expressions of FTO and the adjacent genes that promote adipogenesis and appetite and reduce steatolysis, satiety, and energy expenditure in the carriers. The present review highlights the recent observations on the key FTO polymorphisms that are associated with child and adolescent MetS with an exploration of the molecular mechanisms underlying the development of increased waist circumference, hypertension, and hyperlipidemia in child and adolescent MetS.

Obesity-related parameters in carriers of some BDNF genetic variants may depend on daily dietary macronutrients intake

Some common single-nucleotide polymorphisms of the brain-derived neurotrophic factor (BDNF) gene have been associated not only with the neurodegenerative diseases but also with some eating disorders. The aim of this study was to assess the possible differences in the obesity-related and glucose metabolism parameters between some BDNF genotypes', that may depend on the daily energy and macronutrients intake. In 484 adult participants we performed the anthropometric measurements, body composition analysis, and body fat distribution. The daily dietary intake was assessed using the 3-day food intake diaries. Blood glucose and insulin concentrations were measured at fasting and during oral glucose tolerance tests. Moreover, the visceral adipose tissue/subcutaneous adipose tissue (VAT/SAT) ratio and homeostatic model assessment of insulin resistance were calculated. We noted that participants carrying the GG genotype had lower skeletal muscle mass and fat free mass (FFM) when carbohydrate intake was > 48%, whereas they presented higher fat-free mass (FFM), and surprisingly higher total cholesterol and LDL-C concentrations when daily fiber intake was > 18 g. Moreover, in these subjects we noted higher waist circumference, BMI, and fasting glucose and insulin concentrations, when > 18% of total daily energy intake was delivered from proteins, and higher VAT content and HDL-C concentrations when > 30% of energy intake was derived from dietary fat. Our results suggest that glucose homeostasis and obesity-related parameters in carriers of some common variants of BDNF gene, especially in the GG (rs10835211) genotype carriers, may differ dependently on daily energy, dietary macronutrients and fiber intake.

"GENYAL" Study to Childhood Obesity Prevention: Methodology and Preliminary Results

Objective

This article describes the methodology and summarizes some preliminary results of the GENYAL study aiming to design and validate a predictive model, considering both environmental and genetic factors, that identifies children who would benefit most from actions aimed at reducing the risk of obesity and its complications.

Design

The study is a cluster randomized clinical trial with 5-year follow-up. The initial evaluation was carried out in 2017. The schools were randomly split into intervention (nutritional education) and control schools. Anthropometric measurements, social and health as well as dietary and physical activity data of schoolchildren and their families are annually collected. A total of 26 single nucleotide polymorphisms (SNPs) were assessed. Machine Learning models are being designed to predict obesity phenotypes after the 5-year follow-up.

Settings

Six schools in Madrid.

Participants

A total of 221 schoolchildren (6-8 years old).

Results

Collected results show that the prevalence of excess weight was 19.0, 25.4, and 32.2% (according to World Health Organization, International Obesity Task Force and Orbegozo Foundation criteria, respectively). Associations between the nutritional state of children with mother BMI [β = 0.21 (0.13-0.3), p (adjusted) <0.001], geographical location of the school [OR = 2.74 (1.24-6.22), p (adjusted) = 0.06], dairy servings per day [OR = 0.48 (0.29-0.75), p (adjusted) = 0.05] and 8 SNPs [rs1260326, rs780094, rs10913469, rs328, rs7647305, rs3101336, rs2568958, rs925946; p (not adjusted) <0.05] were found.

Conclusions

These baseline data support the evidence that environmental and genetic factors play a role in the development of childhood obesity. After 5-year follow-up, the GENYAL study pretends to validate the predictive model as a new strategy to fight against obesity.

Clinical Trial Registration

This study has been registered in ClinicalTrials.gov with the identifier NCT03419520, https://clinicaltrials.gov/ct2/show/NCT03419520.

BDNF Gene as a Precision Skill of Obesity Management

The scarcity of the results obtained for the treatment of obesity leads us to consider new strategies, contemplating all the factors involved in the development of the disease. One of the key molecules for controlling body weight and energy homeostasis is the brain-derived neurotrophic factor (BDNF). This work summarizes the mechanisms in which BDNF gene regulates this multifactorial disease. In addition, we discuss the role of other BDNF polymorphisms as genetic determinants of obesity. In this context, a total of 14 SNPs near or inside BDNF/BDNF-AS related to BMI were identified in various GWASs. Finally, we assess gene-diet interaction as a novel tool to prevent obesity and formulate solid and personalized nutritional management. Our research group has performed the first study on the association of BDNF-AS rs925946 polymorphism and calcium intake as potential modulators of the nutritional status. Although these results should be confirmed in future studies, they open the path for new prevention opportunities.

Association of calcium and dairy product consumption with childhood obesity and the presence of a Brain Derived Neurotropic Factor-Antisense (BDNF-AS) polymorphism

BACKGROUND & AIMS

Calcium and dairy products have multiple health benefits. The objective of this work was to evaluate the association between calcium/dairy intake, blood pressure, the BDNF-AS rs925946 polymorphism and nutritional status in a group of schoolchildren.

METHODS

As part of the GENYAL study to childhood obesity prevention, 221 children belonging to different areas of the Community of Madrid were enrolled. Anthropometric and dietary data were collected, and children were genotyped according to the rs925946 polymorphism. Adjusted logistic and linear models were used to describe the data.

RESULTS

A significantly lower consumption of calcium in overweight versus normal weight children was observed (811.0 ± 174.1; 859.0 ± 195.9; 954.0 ± 223.1 mg; for obesity, overweight and normal weight, respectively, p = 0.010). Moreover, an inverse association between blood pressures and calcium intake was detected (β = -0.006 (-0.011, -3e^-4)), p = 0.040. The number of dairy servings/day showed a protective effect against overweight (OR = 0.48 (0.29, 0.75), p = 0.001). Finally, common homozygous children (GG) showed an inverse association between the calcium intake and the BMI (β = -0.003 (-0.006, -0.001), p = 0.004), which was not observed in children carrying the T allele (β = -1.3e^-4 (-0.0022, 0.0024), p = 0.93).

CONCLUSION

Calcium and dairy were strongly associated with the nutritional status and blood pressure. The identification of differential effects of calcium/dairy consumption on the nutritional status according to genetics may contribute to the personalization of future nutritional advice.

TRIAL REGISTRATION

This study is registered at www.clinicaltrials.govNCT03419520.

The Association between Obesity-Risk Genes and Gestational Weight Gain Is Modified by Dietary Intake in African American Women

Obesity-risk genes have been associated with dietary intake, appetite regulation, and gestational weight gain (GWG). The purpose of this study was to examine whether dietary intake including total energy intake and macronutrients modify or mediate the association between obesity-risk genes and GWG. An observational study was conducted with 85 African American pregnant women. Sociodemographic, medical, and lifestyle factors and dietary recalls were collected during pregnancy. Seven obesity-risk genetic variants were genotyped. Regression analyses with bootstrapping methods were used to examine the moderation and mediation effects of dietary intake. The mean GWG was 14.2 kg, and 55.3% of the women gained above the Institute of Medicine GWG guidelines. A nominally significant association was found between rs17782313 (close to MC4R) and percentage of energy intake from fat (P=0.043). A variant downstream of KCTD15 (rs11084753) was nominally significantly related to GWG (P=0.023). There was a significant interaction between the KCTD15 polymorphism and dietary fat intake (P=0.048). Women with the AG genotype gained more weight during pregnancy with more dietary fat consumption. In conclusion, our results indicate that dietary macronutrients, especially fat intake, may modify the effect of the KCTD15 gene on GWG. Improved knowledge of gene-diet interactions can facilitate the development of personalized interventions.

Interaction of BDNF rs6265 variants and energy and protein intake in the risk for glucose intolerance and type 2 diabetes in middle-aged adults

OBJECTIVES

Brain-derived neurotrophic factor (BDNF) is associated with the risk for Alzheimer's disease and type 2 diabetes. The aim of this study was to examine the association of BDNF variants with type 2 diabetes and the interactions of different BDNF genotypes with dietary habits and food and nutrient intakes in middle-aged adults.

METHODS

The study population included 8840 adults ages 40 to 65 y from the Ansan and Asung areas in the Korean Genome Epidemiology Study, a cross-sectional study of Korean adults, conducted from 2001 to 2002. Adjusted odd ratios for the prevalence of glucose intolerance and type 2 diabetes according to BDNF genotypes were calculated after adjusting for age, sex, residence area, body mass index, physical activity, and smoking and stress status. Nutrient intake was calculated from usual food intake determined by semiquantitative food frequencies using the nutrient assessment software.

RESULTS

BDNF rs6265 Val/Met and Met/Met variants were negatively associated with the risk for type 2 diabetes after adjusting for covariates. Serum glucose levels after glucose loading and hemoglobin A1c, but not serum insulin levels, also were negatively associated with BDNF Val/Met and Met/Met. In subgroup analysis, sex and stress levels had an interaction with BDNF Val/Met in the risk for type 2 diabetes. Glucose-intolerant and diabetic, but not nondiabetic, patients with BDNF Met/Met had nominally, but significantly higher intakes of energy than those with BDNF Val/Val. BDNF rs6265 had consistent gene-diet interactions with energy and protein intake. With low-energy, low-protein, and high-carbohydrate intake, BDNF Val/Met lowered the risk for type 2 diabetes after adjusting for confounding factors. BDNF Val/Met did not compensate for developing type 2 diabetes with high-energy intake. Additionally, indexes of insulin resistance and insulin secretion showed the same gene-energy interaction as type 2 diabetes.

CONCLUSIONS

BDNF Val/Met and Met/Met variants (rs6265) decreases the risk for glucose intolerance and type 2 diabetes. BDNF variants interacted with nutrient intake, especially energy and protein intake: Middle-aged individuals with BDNF Val/Val are prone to developing type 2 diabetes even with low energy and protein intake.