Genetic Variants in Antioxidant Genes Modulate the Relationships Among Obesity-Related Oxidative Stress Markers in...

Single-nucleotide polymorphisms (SNPs) in antioxidant genes could influence redox regulation from early life. We aimed to assess the direct and modulatory effects of SNPs in antioxidant genes (SOD2 rs4880, GPX1 rs1050450, GPX7 rs835337, CAT rs1001179) on the relationships among obesity-related oxidative stress markers in Mexican children. Anthropometric data of 2946 unrelated children were analyzed in this cross-sectional study. SNPs were genotyped using TaqMan assay. Serum total antioxidant capacity (sTAC) and oxidative stress markers (thiobarbituric acid reactive substances [TBARS, as lipid peroxidation], and protein carbonyl [PC]) were assessed. Although no SNPs were associated with obesity (p ≥ 0.125), both sTAC (p = 0.001) and TBARS (p = 0.015) were positively associated with it. A negative relationship was also observed between sTAC and TBARS (p < 0.001). SOD2 rs4880 was negatively associated with TBARS, while GPX1 rs1050450 was inversely associated with both TBARS and PC levels (p ≤ 0.036). The inverse association between sTAC and TBARS remained significant only in non-carriers of SOD2 rs4880 (p = 0.003) and GPX1 rs1050450 (p = 0.002). Our data evidence that sTAC and TBARS are associated with obesity, showing a negative relationship in Mexican children who are non-carriers of SOD2 rs4880 and GPX1 rs1050450.