Mecanismos associados às disfunções cardiometabólicas em um modelo experimental de menopausa e síndrome metabólica: papel do treinamento físico aeróbio ou resistido

Abstract

The aim of this study was to evaluate effects of the ovarian hormones deprivation associated with hypertension and fructose overload in metabolic, cardiovascular, autonomic, inflammation and oxidative stress parameters. Additionally aimed to investigate the effects of the dynamic or resistance exercise training this condition by association of the risk factors. Female rats Wistar (n=8) and SHR (n=32) were divided in: normotensive (C), hypertensive (H), hypertensive ovariectomized (HO), hypertensive ovariectomized treated with fructose (FHO), and submitted aerobic exercise training (FHOTa) or resistance exercise training (FHOTr). The aerobic exercise training (treadmill; 1h/day; 5d/wk) and resistance exercise training (ladder adaptated for rats; 1h/day; 5d/wk) were performed during 8 weeks. Cardiovascular function, autonomic cardiovascular modulation, metabolic and physical capacity were evaluated, as weel as the relationship of these variables with cardiac oxidative stress and inflammation in the cardiac and renal tissues. The association of risk factors promoted an exarcebated increase in blood pressure (FHO: 173±1 vs. C:108±1 mmHg). In contrast, was observed resting bradycardia after exercise training (FHO: 393±10 vs. FHOTa:336±9 and FHOTr:330±13bpm). The FHO group showed impairment in the pressoreceptors sensibility, autonomic modulation and lower nitric oxide bioavaliability. Both aerobic and resistance exercise training normalized the RMSSD (parasympathetic modulation index) and increased the pressoreceptors sensibility. TNF alpha and leptin were increased in the FHO group (65.8±9.9 pg/mg protein and 1346.65±127.28pg/ml) in relation to C group (23.66±4.35 pg/mg protein and 974.28±90.90 pg/ml), which was normalized of the trainings. Correlation between TNF alpha and leptin (positive) was obtained in the treated with fructose groups (sedentary and trained). On the other hand, the exercise training promoted higher nitric oxide bioavaliability (FHOTa:0.32±0.2; FHOTr:1.46±0.18 vs. FHO:1.35±0.21 C:1.1±0.15 nmol/mg protein) and increase oh the IL-10 (only FHOTr: 40.25±7.97 vs. FHO:16.26±2.52pg/mg protein). Positive correlation was obtained between RMSSD and IL-10. The fructose overload induced an increase membrane lipoperoxidation in the cardiac tissue (FHO:15043±1333; FHOTa:10652±814; FHOTr:11551±1350 vs. C:2661±358µlmol/mg protein), which was reduced by both types of the training. The FHO group showed increase proteins damage in the renal tissue (FHO:4.40±0.37 vs. C: 1.97±0.21nmol/mg protein) and both exercise training were effective in decrease this variable. Negative correlation was obtained between cardiac RMSSD and QL. Positive correlation was obtained between renal LF-PAS and TBARS. Fructose overload reduced the cardiac TRAP, however, both exercise training enhance this variable. Fructose consumption induced impairment in the redox balance (FHO: 8.2±0.51 vs. C:10.4±0.63), which can be reversed by aerobic (FHOTa: 12.9±0.44) and resistance exercise training (FHOTr:). The redox balance was positively related with RMSSD and negatively correlated with TNF alpha. Concluding, the results evidences that fructose overload induced impairment in the cardiovascular autonomic modulation associated increase inflammatory and oxidative stress parameters in hypertensive ovariectomized rats. Dynamic aerobic or resistance exercise training of the moderate intensity this model of risk factors association attenuated some of the metabolic, cardiovascular and autonomic dysfunctions probably by improving inflammatory markers and oxidative stress.