U.S. Department of Agriculture/Agricultural Research Service, Children's Nutrition Research Center, Baylor College of Medicine, Houston, TX 77030, USA.
Am J Clin Nutr. 2012 Jun;95(6):1487-94. doi: 10.3945/ajcn.111.032045. Epub 2012 May 2.
Isoflavones, having chemical structures similar to estrogens, are believed to stimulate nitric oxide production and thus lower blood pressure. The efficacy of soy isoflavone supplementation to stimulate nitric oxide production and lower blood pressure in menopausal women with high normal blood pressure remains unknown.
The objective was to test the effect of soy isoflavone supplementation on nitric oxide production and blood pressure in menopausal women with high normal blood pressure.
A randomized, double-blind, parallel, placebo-controlled 6-wk trial was conducted to assess the effects of daily supplementation with 80 mg soy hypocotyl isoflavones (in aglycone units) on nitric oxide metabolism and blood pressure in 24 menopausal women with 12 women per group. Changes in nitric oxide metabolism were assessed via a primed, constant-infusion protocol with [15N]arginine and [13C]- and [2H]citrulline. Changes in blood pressure and associated vascular hemodynamics were assessed via office and 24-h ambulatory blood pressure monitoring, forearm blood flow, and indexes of arterial compliance.
When compared with placebo and after control for pretreatment values, soy isoflavone supplementation had no effect on arginine flux, citrulline flux, nitric oxide synthesis, blood pressure, forearm blood flow, or estimates of arterial stiffness.
Daily supplementation with 80 mg soy hypocotyl isoflavones over a 6-wk period had no effect on nitric oxide metabolism or blood pressure and associated vascular hemodynamics in menopausal women with high normal blood pressure.
异黄酮的化学结构与雌激素相似，被认为可以刺激一氧化氮的产生，从而降低血压。然而，关于补充大豆异黄酮是否可以刺激一氧化氮的产生并降低血压正常偏高的绝经后女性的血压，目前还不清楚。
本研究旨在测试大豆异黄酮补充剂对血压正常偏高的绝经后女性一氧化氮产生和血压的影响。
进行了一项随机、双盲、平行、安慰剂对照的 6 周试验，以评估每天补充 80mg 大豆下胚轴异黄酮（以苷元计）对 24 名血压正常偏高的绝经后女性一氧化氮代谢和血压的影响，每组 12 名女性。通过[15N]精氨酸和[13C]-和[2H]瓜氨酸的引物恒速输注方案评估一氧化氮代谢的变化。通过办公室和 24 小时动态血压监测、前臂血流和动脉顺应性指数评估血压和相关血管血流动力学的变化。
与安慰剂相比，并且在控制预处理值后，大豆异黄酮补充剂对精氨酸流量、瓜氨酸流量、一氧化氮合成、血压、前臂血流或动脉僵硬度估计值均无影响。
在 6 周的时间内，每天补充 80mg 大豆下胚轴异黄酮对血压正常偏高的绝经后女性的一氧化氮代谢或血压及相关血管血流动力学没有影响。
