The nutrigenetic influence of the interaction between dietary vitamin E and TXN and COMT gene polymorphisms on waist circumference: a case control study

摘要

Background: Abdominal obesity (AO) is a common modifiable risk factor for certain non-communicable diseasesassociated with enhanced oxidative stress (OS). The objective of this work was to investigate whether the interactionbetween antioxidant vitamin intake and OS-related polymorphisms modulates gene-associated anthropometry in aSpanish population.Methods: A total of 246 subjects with AO, and 492 age and gender matched non-AO subjects were included in thestudy. Anthropometric, biochemical, and OS parameters, and antioxidant dietary intake data were assessed using validatedprocedures. DNA from white blood cells was isolated and the genotype of seven polymorphisms from genesinvolved in OS (pro-oxidant and antioxidant) were analyzed using the SNPlex system. The effects of the c.-793T > Cpolymorphism on promoter activity and thus thioredoxin (TXN) activity were examined using reporter assays.Results: The AO group had higher 8-Oxo-2′-deoxyguanosine levels and took in less vitamin A and vitamin E comparedto the non-AO group. Logistic regression analysis revealed that the rs2301241 polymorphism in TXN andrs740603 in catechol-O-methyltransferase (COMT) were associated with waist circumference (WC) and AO. Moreover,these polymorphisms were more strongly associated with variations in WC in subjects with low vitamin E intakes. Apromoter assay revealed that the T to C conversion at c.-793 (rs2301241) induced a more than two fold increase inreporter gene expression.Conclusions: WC is associated both with dietary vitamin E intake and genetic variants of TXN and COMT suggestingthat existence of a complex nutrigenetic pathway that involves regulation of AO.