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1.
Artigo em Inglês | MEDLINE | ID: mdl-38700469

RESUMO

Preeclampsia is a risk factor for future cardiovascular diseases. However, the mechanisms underlying this association remain unclear, limiting effective prevention strategies. Blood pressure responses to acute stimuli may reveal cardiovascular dysfunction not apparent at rest, identifying individuals at elevated cardiovascular risk. Therefore, we compared blood pressure responsiveness to acute stimuli between previously preeclamptic (PPE) women (34±5yr, 13±6 months postpartum) and women following healthy pregnancies (CTRL; 29±3yr, 15±4 months postpartum). Blood pressure (finger photoplethysmography calibrated to manual sphygmomanometry-derived values; PPE: n=12, CTRL: n=12) was assessed during end-expiratory apnea, mental stress, and isometric handgrip exercise protocols. Integrated muscle sympathetic nerve activity (MSNA) was assessed in a subset of participants (peroneal nerve microneurography; PPE: n=6, CTRL: n=8). Across all protocols, systolic blood pressure (SBP) was higher in PPE than CTRL (main effects of group all P<0.05). Peak changes in SBP were stressor-specific: peak increases in SBP were not different between PPE and CTRL during apnea (+8±6 vs. +6±5mmHg, P=0.32) or mental stress (+9±5 vs. +4±7mmHg, P=0.06). However, peak exercise-induced increases in SBP were greater in PPE than CTRL (+11±5 vs. +7±7mmHg, P=0.04). MSNA was higher in PPE than CTRL across all protocols (main effects of group all P<0.05), and increases in peak MSNA were greater in PPE than CTRL during apnea (+44±6 vs. +27±14burst/100hb, P=0.04) and exercise (+25±8 vs. +13±11burst/100hb, P=0.01) but not different between groups during mental stress (+2±3 vs. 0±5burst/100hb, P=0.41). Exaggerated pressor and sympathetic responses to certain stimuli may contribute to the elevated long-term risk for cardiovascular disease in PPE.

2.
Arch Gynecol Obstet ; 309(1): 17-36, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-36920532

RESUMO

INTRODUCTION: Polycystic ovary syndrome (PCOS) is a common endocrinopathy associated with cardiometabolic dysfunction. PURPOSE: (1) To compare HRPF indices, including cardiorespiratory fitness (CRF), muscle strength, and muscle endurance, between women with and without PCOS (i.e., controls). (2) To explore the impact of moderating factors, i.e., insulin sensitivity, androgen levels, physical activity levels, and body mass index, on these indices. METHODS: Articles comparing HRPF between PCOS and control groups were identified until February 27th, 2022. Random-effects meta-analyses were conducted and moderating factors were explored with subgroup and meta-regression analyses. RESULTS: Twenty studies were included. Compared to controls, CRF was lower in women with PCOS (n = 15, - 0.70 [- 1.35, - 0.05], P = 0.03, I2 = 95%). Meta-regression analyses demonstrated that fasting insulin (P = 0.004) and homeostatic model assessment of insulin resistance (P = 0.006) were negatively associated with CRF, while sex-hormone binding globulin levels (P = 0.003) were positively associated. Absolute muscle strength was not different between PCOS and controls (n = 7, 0.17 [- 0.10, 0.45], P = 0.22, I2 = 37%). One study evaluated muscle endurance and reported lower core endurance in PCOS subjects compared to controls. CONCLUSION: These data suggest that PCOS may be associated with impaired CRF. It remains unclear whether muscle strength and endurance differ between women with PCOS and controls. As this data set was limited by a small sample size, potential for bias, and inconsistent findings, additional studies accounting for the heterogeneous presentation of PCOS as well as improved matching between PCOS and controls for characteristics known to affect HRPF would help elucidate the impact of PCOS on indices of HRPF. PROSPERO REGISTRATION NUMBER: CRD42020196380.


Assuntos
Resistência à Insulina , Síndrome do Ovário Policístico , Feminino , Humanos , Síndrome do Ovário Policístico/metabolismo , Resistência à Insulina/fisiologia , Insulina , Força Muscular/fisiologia , Aptidão Física , Índice de Massa Corporal
3.
Exp Physiol ; 108(10): 1250-1256, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37642329

RESUMO

Polycystic ovary syndrome (PCOS) is a complex disorder characterized by reproductive abnormalities, cardiometabolic disturbances and a heightened risk of cardiovascular disease. A small but compelling body of research demonstrates that females with PCOS present with elevated muscle sympathetic nerve activity (MSNA) at rest. Heightened MSNA is present in lean, overweight and obese females with PCOS, but limited evidence suggests that androgens may be more strongly linked to elevated MSNA in lean females with PCOS than in obese females with PCOS. Although the specific mechanisms underlying elevated MSNA in PCOS remain elusive, sympathetic activation is implicated in the progression of several cardiovascular diseases and may contribute to the cardiovascular pathophysiology of PCOS. Encouragingly, MSNA appears responsive to non-pharmacological intervention, making the sympathetic nervous system a promising therapeutic target to mitigate cardiovascular risk in PCOS. This brief review summarizes the existing evidence regarding elevated MSNA, cardiovascular risk profile and vascular function, as well as the potential for clinical intervention and future research directions in females with PCOS. NEW FINDINGS: What is the topic of this review? The presence of elevated muscle sympathetic nerve activity in females with polycystic ovary syndrome and the implications for cardiovascular health. What advance does it highlight? The sympathetic nervous system likely contributes to elevated cardiovascular disease risk in females with polycystic ovary syndrome. Moreover, it presents as a promising therapeutic target for mitigating cardiovascular disease and merits further investigation.


Assuntos
Doenças Cardiovasculares , Síndrome do Ovário Policístico , Feminino , Humanos , Sistema Nervoso Simpático , Obesidade , Músculos
4.
J Appl Physiol (1985) ; 134(4): 868-878, 2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-36861670

RESUMO

Polycystic ovary syndrome (PCOS) is associated with endothelial dysfunction; whether this is attributable to comorbid hyperandrogenism and/or obesity remains to be established. Therefore, we 1) compared endothelial function between lean and overweight/obese (OW/OB) women with and without androgen excess (AE)-PCOS and 2) examined androgens as potential modulators of endothelial function in these women. The flow-mediated dilation (FMD) test was applied in 14 women with AE-PCOS (lean: n = 7; OW/OB: n = 7) and 14 controls (CTRL; lean: n = 7, OW/OB: n = 7) at baseline (BSL) and following 7 days of ethinyl estradiol supplementation (EE; 30 µg/day) to assess the effect of a vasodilatory therapeutic on endothelial function; at each time point we assessed peak increases in diameter during reactive hyperemia (%FMD), shear rate, and low flow-mediated constriction (%LFMC). BSL %FMD was attenuated in lean AE-PCOS versus both lean CTRL (5.2 ± 1.5 vs. 10.3 ± 2.6%, P < 0.01) and OW/OB AE-PCOS (5.2 ± 1.5 vs. 6.6 ± 0.9%, P = 0.048). A negative correlation between BSL %FMD and free testosterone was observed in lean AE-PCOS only (R2 = 0.68, P = 0.02). EE increased %FMD in both OW/OB groups (CTRL: 7.6 ± 0.6 vs. 10.4 ± 2.5%, AE-PCOS: 6.6 ± 0.9 vs. 9.6 ± 1.7%, P < 0.01), had no impact on %FMD in lean AE-PCOS (5.17 ± 1.5 vs. 5.17 ± 1.1%, P = 0.99), and reduced %FMD in lean CTRL (10.3 ± 2.6 vs. 7.6 ± 1.2%, P = 0.03). Collectively, these data indicate that lean women with AE-PCOS exhibit more severe endothelial dysfunction than their OW/OB counterparts. Furthermore, endothelial dysfunction appears to be mediated by circulating androgens in lean but not in OW/OB AE-PCOS, suggesting a difference in the endothelial pathophysiology of AE-PCOS between these phenotypes.NEW & NOTEWORTHY We present evidence for marked endothelial dysfunction in lean women with androgen excess polycystic ovary syndrome (AE-PCOS) that is 1) associated with free testosterone levels, 2) impaired relative to overweight/obese women with AE-PCOS, and 3) unchanged following short-term ethinyl estradiol supplementation. These data indicate an important direct effect of androgens on the vascular system in women with AE-PCOS. Our data also suggest that the relationship between androgens and vascular health differs between phenotypes of AE-PCOS.


Assuntos
Síndrome do Ovário Policístico , Humanos , Feminino , Síndrome do Ovário Policístico/complicações , Síndrome do Ovário Policístico/terapia , Androgênios , Sobrepeso/complicações , Índice de Massa Corporal , Obesidade , Etinilestradiol/farmacologia , Testosterona
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