Respostas a testes de estresse metabólico, mental e físico em mulheres jovens com histórico familiar de hipertensão arterial e obesidade

Abstract

Arterial hypertension (SAH) is an important cause of morbidity and mortality. Heredity is a risk factor for non-modifiable SAH, with reports of additional increase in blood pressure and muscle sympathetic nerve activity in response to mental or physical stimulus in offspring of hypertensive parents. Recently, we demonstrated that the presence of overweight was associated with exacerbation of autonomic impairment and the presence of oxidative stress markers in men with a positive history of SAH even at rest. Despite this evidence, it is worth noting that female samples have been neglected or underestimated in clinical and experimental studies, as well as in studies focusing on heredity, despite the strong trend towards increased cardiovascular mortality among women in recent years. Thus, in this thesis, we evaluated the influence of the positive family history of SAH, associated or not with overweight/obesity, on cardiovascular, autonomic, inflammatory and oxidative stress adjustments to mental, physical and metabolic stimulus in women. A cross-sectional clinical study was carried out. Forty female subjects between 18-30 years old, were selected and divided into 4 groups: groups with negative (FNE, n = 09) or positive (FHE, n = 11) family history of SAH and eutrophics and groups with negative (FNO, n = 09) or positive (FHO, n = 11) family history of SAH and overweight/obesity. The subjects were submitted to three stresses maneuvers: 1) Mental, by applying the Stroop-Color Word Test (SCWT); 2) Physical, through isometric exercise with Hand Grip (HG, 30% maximum load for 90 seconds) and 3) Metabolic, induced by acute fructose intake (30 g of fructose [10%] in 300 ml of water with lemon juice). Cardiovascular and autonomic assessments were performed before and after tests; and inflammatory markers and oxidative stress before and after metabolic stress test. As a result, there were higher sysolic arterial pressure (SAP) and VAR-SAP in the FNO (34.4 ± 9.3 mmHg²) and FHO groups (37.1 ± 8.3 mmHg²) compared to the eutrophic groups (FNE- 23.0 ± 7.0 mmHg²) and FHE- 22.6 ± 8.8 mmHg²), but only the FHO group showed a greater vascular sympathetic (BF abs SBP) when compared to eutrophic groups. Only groups with a positive history of SAH (FHE and FHO) showed a reduction in the antioxidant enzyme activity GPx when compared to groups with a negative history of SAH (FNE and FNO). In addition, the association of factors (FHO group) increased the values of nitrosative stress (nitrite: FNO- 0.99 ± 0.47 vs. FNE- 0.44 ± 0.29 and FHE- 0.30 ± 0.19 nmol/mg protein), as well as of protein oxidation (FHO vs. eutrophic groups) and of NADPH oxidase activity (FHO vs. all groups). Responses to mental stress in the 3rd minute showed an increase in SBP in FHE, FNO and FHO groups compared to their respective baseline values. In addition, exacerbated response in the 3rd minute to SBP was observed in FNO and FHO groups compared to the FNE group and to PAD in the FHO group when compared to the FNE group. The FHE, FNO and FHO groups also showed higher VAR-SAP (FHE- 39.9 ± 10.7; FNO- 41.1 ± 12.9; FHO- 43.0 ± 14.7 vs. FNE- 24.1 ± 9.1 mmHg²) and BF abs SAP in relation to the FNE group after SCWT. In physical stress, the results showed that HR increased exacerbated at 90 seconds of HG in the FNO groups when compared to the FNE group, and in the FHO group in relation to the FNE and FHE groups. There was also an exacerbated response to increased VAR-SAP and BF abs SAP in the FHE and FHO groups compared to the FNE group post HG. Only the FHO group (6.6 ± 1.3 ms/mmHg) showed reduced baroreflex sensitivity (alpha index) when compared to the FNE group (10.3 ± 1.0 ms / mmHg) after exercise with HG. Regarding metabolic stimulus, the results showed a higher SBP in the FHE and FHO groups compared to the FNE group. The Δ SBP (post- basal of fructose) was higher in the groups with a positive history of SAH (FHE- 13.1 ± 7.1 and FHO- 11.0 ± 9.6 vs. FNE- 0.8 ± 6.4 mmHg). The VAR-SAP was higher in the FHE and FHO groups compared to the FNE group and all groups increased exacerbated vascular sympathetic modulation when compared to the FNE group, but only the FHO group had a decrease in the alpha index (6.9 ± 1.2 ms / mmHg) in relation to the FHE group (10.8 ± 2.6 ms / mmHg) in post-fructose. All 11 groups showed a reduction in GPx activity in relation to their baseline values after frutose. The overweight/obese groups showed higher values of plasma nitrites after fructose when compared to the eutrophic groups (FNO- 0.89 ± 0.51 and FHO- 0.88 ± 0.14 vs. FNE- 0.33 ± 0.19 and FHE- 0.34 ± 0.11 nmol/mg protein) and there was an increase in NADPH oxidase activity in the FHO group compared to the FNE group post-fructose. In conclusion, the results showed that young adult women with a family history of SAH and overweight/obesity already had baseline conditions with increased SBP, within the normal range, impaired on heart rate variability and on arterial pressure variability (HRV and APV), associated with increased markers of nitrosative and oxidative stress; and these changes being exacerbated in response to physiological stimulus maneuvers. However, eutrophic women with a positive history of SAH, clinically normal at rest, showed pressoric and APV responses impaired only when subjected to mental, physical and metabolic stimulus, as well as increased oxidative stress markers after acute fructose intake. These findings suggest that the assessment of HRV and APV in a non-invasive way can be used as an early biomarker of dysfunctions associated with the development of SAH in women, mainly exposed to genetic or environmental risk factors.