Alteração epigenética no gene BDNF, status social e de saúde como preditores da insegurança alimentar e nutricional em cafeicultores familiares

Introduction: state of Food and Nutritional Security (FNS) is one that should guarantee the right of permanent access to quality food and in sufficient quantity without prejudicing access to other basic rights. In Brazil, rural family farming establishments represent 84.4% of total agricultural establishments and contribute to more than 70% of all food consumed by Brazilians. In this context, the production of the coffee commodity stands out. However, despite being food producers, they do not earn a good income. Slow economic activity can lead to loss of wages and income, illness, as well as food insecurity (FNiS). In addition, the molecular effects of FNiS are poorly studied, especially epigenetic. Objective: the objective of the present study is to analyze the association between Brain-Derived Neurotrophic Factor (BDNF) DNA methylation and socio demographic, lifestyle, and epigenetic factors, among coffee farmers in the Caparaó zone, in Espirito Santo, Southeast Brazil. Methods: the study was carried out in 22 randomly selected coffee producing communities in Zona Caparaó, an area that produces coffee of recognized quality. A total of 570 coffee farming households, 18 to 60 years of age, were included in the study by answering a questionnaire about socioeconomic characteristics, land use and ownership, behavior, health, and working conditions. FNiS evaluation was carried out using the Brazilian Food Insecurity Scale. BDNF exon I methylation was examined by methylation-specific PCR. Body mass index and biochemical analyses were performed. Logistic regression models were used to verify factors associated with FNiS (p<0.05). Data were analyzed using the Stata® statistical software package version 14. Results: the FNiS prevalence found was 23.68%. In multivariable logistic regression, the occurrence of FNiS was associated with hypermethylation of exon I of the BDNF promoter exon I [ORa = 5.03 (95% (1.98, 12.82)] when compared to the unmethylated gene. Moreover, FNiS was associated with excessive workload [ORa = 3.36 (1.23, 9.22)], possession of less land (hectares) [ORa = 0.77 (0.67, 0.90)] and greater number symptoms and / or illnesses in real life [ORa = 1.12 (1.04.1.20)]. Conclusion: there is a high prevalence of Food Insecurity in the studied region. This phenomenon was associated with epigenetic factors (BDNF methylation), excessive workload, small land ownership and a greater number of diseases / symptoms. Food insecurity is a psychosocial stressor that can lead to epigenetic changes in the BDNF gene, responsible for regulating cognitive functions, neuronal survival and involved in the genesis of psychiatric diseases.Introdução: o Estado de Segurança Alimentar e Nutricional (SAN) é aquele que deve garantir o direito de acesso permanente à alimentação de qualidade e em quantidade suficiente sem prejudicar o acesso a outros direitos básicos. No Brasil, os estabelecimentos de agricultura familiar rural representam 84,4% do total de estabelecimentos agropecuários e contribuem com mais de 70% de todos os alimentos consumidos pelos brasileiros. Nesse contexto, destaca-se a produção da commodity café. No entanto, apesar de serem produtores de alimentos, não auferem bons rendimentos. A lenta atividade econômica pode levar à perda de salários e renda, doenças e insegurança alimentar (INSAN). Além disso, os efeitos moleculares da INSAN são pouco estudados, sobretudo epigenéticos. Objetivos: o objetivo do presente estudo é analisar a associação entre a metilação do promotor do BDNF e a INSAN e a associação da INSAN com fatores sociodemográficos, de estilo de vida e epigenéticos, em cafeicultores da zona do Caparaó, no Espírito Santo, Sudeste do Brasil. Método: o estudo foi realizado em 22 comunidades cafeeiras selecionadas aleatoriamente na Zona do Caparaó, área que produz café de reconhecida qualidade. Um total de 570 famílias de cafeicultores, entre 18 a 60 anos, foram incluídos no estudo e responderam a um questionário sobre características socioeconômicas, uso e posse da terra, hábitos de vida, saúde e condições de trabalho. A avaliação da INSAN foi realizada por meio da Escala Brasileira de Insegurança Alimentar. A metilação do éxon I do BDNF foi examinada por PCR específica para metilação. Índice de massa corporal e análises bioquímicas foram realizadas. Modelos de regressão logística foram utilizados para verificar os fatores associados à INSAN (p<0,05). Os dados foram analisados usando o software estatístico Stata® versão 14. Resultados: a prevalência de INSAN encontrada foi de 23,68%. Na regressão logística multivariada, a ocorrência de INSAN foi associada a hipermetilação do éxon I do promotor do gene BDNF [ORa = 5,03 (95% (1,98, 12,82)] quando comparado ao gene não metilado. Além disso, a INSAN foi associada a carga de trabalho excessiva [ORa = 3,36 (1,23, 9,22)], posse de menos hectares de terra [ORa = 0,77 (0,67, 0,90)] e maior número de sintomas e/ou doenças da vida real [ORa = 1,12 (1.04.1.20)]. Conclusão: o estudo mostrou uma alta prevalência de Insegurança Alimentar na região analisada. Esse fenômeno foi associado a fatores epigenéticos (metilação do gene BDNF), carga horária excessiva, pequena propriedade de terra e maior número de doenças/sintomas. A INSAN pode ser um estressor capaz de promover alterações epigenéticas no gene BDNF, importante gene regulador da cognição, crescimento e sobrevivência neuronal e envolvido com doenças psiquiátricas

Psychosocial stress and central adiposity: A Brazilian study with a representative sample of the public health system users.

OBJECTIVE:To assess the association between indicators of psychosocial stress and central adiposity in adult users of the Unified Health System (SUS) from Southeast of Brazil. METHODS:This cross-sectional study was conducted with 384 adults (20 to 59 years old) from the city of Alegre, Southeastern Brazil. The simple random sample represented the population using the public health system of the municipality. The prevalence of obesity was based on the Body Mass Index, and central adiposity (dependent variable) was measured by waist circumference in centimeters. The independent variables were the following indicators of psychosocial stress: food and nutrition insecurity (yes/no), serum cortisol (μg/dL), symptoms suggestive of depression using the Beck Depression Inventory-II ≥ 17 (yes/no), and altered blood pressure ≥ 130/85 mmHg (yes/no). Univariate linear regression was performed between central adiposity and each stress indicator, and later the models were adjusted for socioeconomic, health, and lifestyle variables. All analyses were made separately by rural and urban location. RESULTS:The prevalence of weight excess, by the classification of the Body Mass Index ≥ 25.0 kg/m2, was 68.3% and, by waist circumference, 71.5% of individuals presented an increased risk for metabolic complications related to central adiposity. Mean waist circumference scores for the rural and urban population were 89.3 ± 12.7 cm and 92.9 ± 14.7 cm, respectively (p = 0.012). Indicators of stress that were associated with central adiposity were: cortisol in the rural population (β = -0.60; 95% CI = -1.09;-0.11) and altered blood pressure in the urban population (β = 6.66; 95% CI = 2.14;11.18). This occurred both in the raw analysis and in the models adjusted for confounding factors. CONCLUSION:Central adiposity was inversely associated with cortisol in the rural population and directly associated with higher arterial blood pressure in the urban population, suggesting a local influence on how individuals react to stress

Association between indicators of stress and central adiposity in the rural population.

<p>Association between indicators of stress and central adiposity in the rural population.</p

Association between indicators of stress and central adiposity in the urban population.

<p>Association between indicators of stress and central adiposity in the urban population.</p

Characteristics of the population according to rural and urban locations.

<p>Characteristics of the population according to rural and urban locations.</p