ANÁLISE DE METILAÇÃO DO GENE PRKAA2 (AMPKα2) EM GÊMEOS MONOZIGÓTICOS DISCORDANTES PARA APTIDÃO CARDIORRESPIRATÓRIA

Abstract

The low cardiorespiratory fitness (VO2máx) has been associated with molecular and biochemical disturbances that influence the glucose metabolism and lipid profile. However, it is unclear whether this association is confounded by genetic factors. The case-control model (monozygotic twins (MZ) discordant) used in this study, cross-sectional, evaluated 09 pairs of MZ twins aged 13,9±2,2 years, which showed intra-pair difference for the VO2máx of 16,9% to 41,6% (from 10,4 to 22,5 ml.kg-1.min-1). Once verified the difference in cardiorespiratory fitness between the brothers, that with the highest VO2max integrated the group TWIN-1, and consequently its co-twin, was part of the group TWIN-2. The objective was to investigate the impact of disagreement in the VO2máx in the PRKAA2 (AMPKα2) gene methylation its relationship to with the glucose metabolismo and lipid profile, independent of genomic effects. We obtained anthropometric measurements of weight, height, waist circumference, and skinfold thickness. A maximal exercise test on a treadmill with direct analysis of gases was used for determination of VO2máx and blood fasting and post-glucose load (OGTT) was collected for laboratory tests, and estimation of HOMA-IR and HOMA-β, lipid profile, besides the extraction of genomic DNA for methylation analysis. The results revealed no differences between the twins with higher (TWIN 1) and lower (TWIN 2) VO2máx in anthropometric variables, HOMA-IR and HOMA-β, lipid profile, and gene methylation PRKAA2. However, we observed a low fasting blood glucose concentration in TWIN-1 compared to TWIN-2. Still, it was observed that the group TWIN-1, there was a negative relationship between methylation and gene PRKAA2 HDL-C, whereas in the group TWIN-2 was positive relationship between methylation and total cholesterol and LDL-C. In conclusion, when genetic factors are controlled, children and adolescents with low VO2máx are likely to have higher fasting glucose concentration. Methylation of PRKAA2 gene appears to be positively related to TC and LDL-C. This study is evidence that an increase in VO2max can have determining effects on glucose metabolism in children and adolescents.