Alvares Thiago Silveira, Maturana Felipe Mattioni, Soares Rogerio Nogueira
Multidisciplinary Center UFRJ-Macaé, Federal University of Rio de Janeiro, Macaé, Rio de Janeiro, Brazil.
Sports Medicine Department, University Hospital of Tubingen, Tubingen, Germany.
Maturitas. 2024 Nov;189:108115. doi: 10.1016/j.maturitas.2024.108115. Epub 2024 Sep 13.
Aging is associated with an increased risk of cardiovascular disease and vascular dysfunction. Reduced nitric oxide bioavailability is considered one of the key mechanisms underlying vascular dysfunction in large arteries of older adults. However, the relationship between cardiovascular disease risk factors, nitric oxide bioavailability, and skeletal muscle microvascular reactivity, an early hallmark in cardiovascular disease progression, is unclear in older individuals. Also uncertain is whether this relationship is influenced by sex. Therefore, this study assessed the association between cardiovascular disease risk factors, circulating markers of nitric oxide availability (plasma nitrate and nitrite), and skeletal muscle microvascular reactivity in older individuals. First, we confirmed in a cohort of young and older individuals that aging is associated with skeletal muscle microvascular dysfunction. Next, we observed that skeletal muscle microvascular reactivity (P = 0.653; η = 0.016) and circulating nitric oxide metabolites (Nitrate: P = 0.641, η = 0.011; Nitrite: P = 0.560, η = 0.017; NOx: P = 0.639, η = 0.011) did not differ between older males and females. Finally, using multivariate regression models, we found that: (i) the number of cardiovascular risk factors was negatively associated with skeletal muscle microvascular reactivity in older males and females (B = -0.132, P = 0.044); (ii) the relationship between plasma nitrite and skeletal muscle microvascular reactivity was influenced by sex (F = 6.837, P = 0.016); and (iii) skeletal muscle microvascular reactivity in older females displayed a strong positive association with plasma nitrite (R = 0.720, P < 0.001). While the impact of cardiovascular disease risk factors on skeletal muscle microvascular reactivity was not influenced by sex, sex-related discrepancies were found in the relationship between nitric oxide bioavailability and skeletal muscle microvascular reactivity in older individuals.
衰老与心血管疾病风险增加及血管功能障碍相关。一氧化氮生物利用度降低被认为是老年人大动脉血管功能障碍的关键机制之一。然而，在老年人中，心血管疾病风险因素、一氧化氮生物利用度与骨骼肌微血管反应性（心血管疾病进展的早期标志）之间的关系尚不清楚。同样不确定的是这种关系是否受性别影响。因此，本研究评估了老年人心血管疾病风险因素、一氧化氮可用性的循环标志物（血浆硝酸盐和亚硝酸盐）与骨骼肌微血管反应性之间的关联。首先，我们在一组年轻人和老年人中证实，衰老与骨骼肌微血管功能障碍相关。接下来，我们观察到老年人男性和女性之间的骨骼肌微血管反应性（P = 0.653；η = 0.016）和循环一氧化氮代谢产物（硝酸盐：P = 0.641，η = 0.011；亚硝酸盐：P = 0.560，η = 0.017；氮氧化物：P = 0.639，η = 0.011）没有差异。最后，使用多元回归模型，我们发现：（i）心血管风险因素的数量与老年人男性和女性的骨骼肌微血管反应性呈负相关（B = -0.132，P = 0.044）；（ii）血浆亚硝酸盐与骨骼肌微血管反应性之间的关系受性别影响（F = 6.837，P = 0.016）；（iii）老年女性的骨骼肌微血管反应性与血浆亚硝酸盐呈强正相关（R = 0.720，P < 0.001）。虽然心血管疾病风险因素对骨骼肌微血管反应性的影响不受性别影响，但在老年人中，一氧化氮生物利用度与骨骼肌微血管反应性之间的关系存在性别差异。
