Epigenetic alteration of BDNF gene, social and health status as predictors of food and nutrition insecurity among familiar coffee farmers
Authors: Miranda Barbosa Wagner , César Jorden Almança Carlos , Vitorino Fretias Flavia , Conti Catarine , De Assis Pinheiro Julia , Almeida de Barros Alcemi , Gasparini dos Santos Joaquim , Ribeiro Borçoi Aline , Batista Pavesi Simão João , Daniele Cardoso Luciane , Krüger Arpini Juliana , Mota de Oliveira Mayara , Dalbó Juliana , Barros Archanjo Anderson , Oliveira Mendes Suzanny , De Lima Maia Lucas , Louro Iúri , Madeira Álvares-da-Silva Adriana 
Published: November 2022

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.