Association of Inflammatory and Oxidative Stress Biomarkers Adjusted by Personal, Psychological, Biochemical, Anthropometric, and Physiological Variables with Global DNA Methylation in a Sample of Mexican Individuals

Global DNA methylation has been associated with numerous traits and conditions; however, its relationship with inflammation and oxidative stress biomarkers has not been fully elucidated. The objective of this study is to determine the correlation between inflammatory and oxidative stress markers with global DNA methylation after adjusting for personal, psychological, biochemical, anthropometric, and physiological variables in a non-representative sample of the Mexican population. An adult Mexican population was invited to participate and complete a questionnaire with personal and psychological variables. Additionally, anthropometric variables and blood pressure were measured in all the participants. Finally, general blood tests, global DNA methylation analysis, and measurements of inflammatory and oxidative stress markers were performed. A total of 157 participants were included, of which 83 (52.8%) were women, with a median age of 24 years and an age range of 18-58 years. In the comparison between sexes, men showed higher levels of global DNA methylation. In addition, men showed a higher number of correlations with this variable. The bivariate correlations showed low positive correlations of IL-8, IL-10, TNF-α, and 8-isoprostane with global DNA methylation in the total sample. In addition, BMI showed low negative and significant correlations with global DNA methylation in the total, women's, and men's samples, while blood pressure showed low negative correlations with global DNA methylation in the men's sample. Men showed low negative correlations with personal and biochemical variables that were not found in the women's group. In the multivariate analyses, the psychological variables (SOC-13 comprehensibility, perceived stress, and assertiveness) correlated negatively either in the total, or in men's or women's samples, and the daily intake of drugs correlated negatively with methylation in the women's sample in the bivariate and multivariate analyses. In conclusion, global DNA methylation seems to be related to many variables, including the inflammatory and oxidative stress biomarkers, and this relationship is different in each sex.