Association between endothelial nitric oxide synthase and the renin-angiotensin-aldosterone system polymorphisms, blood pressure and training status in normotensive/pre-hypertension and hypertensive older adults: a pilot study

Abstract

Introduction:Variations in blood pressure (BP) are, in part, genetically determined and some polymorphisms of renin-angiotensin- aldosterone system (RAAS) and synthase of endothelial nitric oxide (eNOS) have been related to hypertension (HT). Conversely, physical exercise is considered a non-pharmacological tool for HT control, treatment, and prevention. Objective: The purpose of this study is to investigate the relationship between eNOS and RAAS polymorphisms, their epistatic interaction, and the respective humoral factors in the BP control in normotensive/pre-hypertension and hypertensive older adults and how this relationship can be modulated by training status (TS) level. Methods:A total of 155 older adults (66.94 ± 6.83 years old) performed the following evaluations: AAHPERD battery test to determine the general functional fitness index (GFFI), systolic and diastolic blood pressure (SBP and DBP), blood collection for DNA extraction, analysis of eNOS gene polymorphisms rs2070744; rs61722009 and rs1799983 and RAAS polymorphisms rs699; rs1799752 and rs5186, and quantification of ACE activity (Fluorimetric Assay) and nitrite concentration (Chemiluminescence Method). Results and Conclusion:Good TS level appears to exert greater influence on SBP for G2 and G3 (G1: 125.79 ± 14.03/ G2: 119.91 ± 11.72/G3: 119.71 ± 10.85) and on NO2 for G3 (G1: 0.42 ± 0.25/ G2: 0.54 ± 0.45/ G3: 0.71 ± 0.52). No associations were observed between eNOS and RAAS polymorphisms, but the epistasis was identified between eNOS polymorphism, rs2070744, and RAAS polymorphism, rs699, revealing a statistically significant interaction (p = .0235) with training score of 0.63, a training test accuracy of 0.61 and a cross-validation consistency of 10/10. This result suggests an increased risk of hypertension.