PDF(Pubmed)
Abstract：
UNASSIGNED: Cardiovascular disease (CVD) is the leading cause of death in women, with increased risk following menopause. Dietary intake of beetroot juice and other plant-based nitrate-rich foods is a promising non-pharmacological strategy for increasing systemic nitric oxide and improving endothelial function in elderly populations. The purpose of this randomized, placebo-controlled, double-blind, crossover clinical trial was to determine the effects of short-term dietary nitrate (NO3 -) supplementation, in the form of beetroot juice, on resting macrovascular endothelial function and endothelial resistance to whole-arm ischemia-reperfusion (IR) injury in postmenopausal women at two distinct stages of menopause.
UNASSIGNED: Early-postmenopausal [1-6 years following their final menstrual period (FMP), n = 12] and late-postmenopausal (6+ years FMP, n = 12) women consumed nitrate-rich (400 mg NO3 -/70 mL) and nitrate-depleted beetroot juice (approximately 40 mg NO3 -/70 mL, placebo) daily for 7 days. Brachial artery flow-mediated dilation (FMD) was measured pre-supplementation (Day 0), and approximately 24 h after the last beetroot juice (BR) dose (Day 8, post-7-day BR). Consequently, FMD was measured immediately post-IR injury and 15 min later (recovery).
UNASSIGNED: Results of the linear mixed-effects model revealed a significantly greater increase in resting FMD with 7 days of BRnitrate compared to BRplacebo (mean difference of 2.21, 95% CI [0.082, 4.34], p = 0.042); however, neither treatment blunted the decline in post-IR injury FMD in either postmenopausal group. Our results suggest that 7-day BRnitrate-mediated endothelial protection is lost within the 24-h period following the final dose of BRnitrate.
UNASSIGNED: Our findings demonstrate that nitrate-mediated postmenopausal endothelial protection is dependent on the timing of supplementation in relation to IR injury and chronobiological variations in dietary nitrate metabolism.
UNASSIGNED: https://classic.clinicaltrials.gov/ct2/show/NCT03644472.
UNASSIGNED: Early-postmenopausal [1-6 years following their final menstrual period (FMP), n = 12] and late-postmenopausal (6+ years FMP, n = 12) women consumed nitrate-rich (400 mg NO3 -/70 mL) and nitrate-depleted beetroot juice (approximately 40 mg NO3 -/70 mL, placebo) daily for 7 days. Brachial artery flow-mediated dilation (FMD) was measured pre-supplementation (Day 0), and approximately 24 h after the last beetroot juice (BR) dose (Day 8, post-7-day BR). Consequently, FMD was measured immediately post-IR injury and 15 min later (recovery).
UNASSIGNED: Results of the linear mixed-effects model revealed a significantly greater increase in resting FMD with 7 days of BRnitrate compared to BRplacebo (mean difference of 2.21, 95% CI [0.082, 4.34], p = 0.042); however, neither treatment blunted the decline in post-IR injury FMD in either postmenopausal group. Our results suggest that 7-day BRnitrate-mediated endothelial protection is lost within the 24-h period following the final dose of BRnitrate.
UNASSIGNED: Our findings demonstrate that nitrate-mediated postmenopausal endothelial protection is dependent on the timing of supplementation in relation to IR injury and chronobiological variations in dietary nitrate metabolism.
UNASSIGNED: https://classic.clinicaltrials.gov/ct2/show/NCT03644472.
摘要：
心血管疾病（CVD）是女性死亡的主要原因，更年期后风险增加。饮食摄入甜菜根汁和其他富含植物硝酸盐的食物是一种有前途的非药物策略，可增加全身一氧化氮并改善老年人群的内皮功能。这个随机化的目的，安慰剂对照,双盲,交叉临床试验是为了确定短期膳食硝酸盐（NO3-）补充的效果，以甜菜根汁的形式，在两个不同的绝经阶段，绝经后妇女静息大血管内皮功能和内皮抵抗全臂缺血再灌注（IR）损伤。
■绝经后早期[最后一次月经期（FMP）后1-6年，n=12]和绝经后期（6年以上FMP，n=12）妇女食用富含硝酸盐（400mgNO3-/70mL）和硝酸盐耗尽的甜菜根汁（约40mgNO3-/70mL，安慰剂)每天持续7天。补充前测量肱动脉血流介导的扩张（FMD）（第0天），以及在最后一次甜菜根汁(BR)剂量后约24小时(第8天,第7天后BR)。因此,在IR损伤后立即测量FMD,并在15分钟后(恢复)测量FMD。
■线性混合效应模型的结果表明，与BR安慰剂相比，服用BRnitrate7天的静息口蹄疫明显增加（平均差异为2.21，95％CI[0.082，4.34]，p=0.042)；然而，两种治疗方法均未缓解绝经后任何一组IR损伤后FMD的下降.我们的结果表明，在最终剂量的硝酸酯后的24小时内，硝酸酯介导的7天内皮保护作用丧失。
■我们的研究结果表明，硝酸盐介导的绝经后内皮保护依赖于补充时间与IR损伤和饮食硝酸盐代谢的时间生物学变化有关。
■https://classic.clinicaltrials.gov/ct2/show/NCT03644472.
■绝经后早期[最后一次月经期（FMP）后1-6年，n=12]和绝经后期（6年以上FMP，n=12）妇女食用富含硝酸盐（400mgNO3-/70mL）和硝酸盐耗尽的甜菜根汁（约40mgNO3-/70mL，安慰剂)每天持续7天。补充前测量肱动脉血流介导的扩张（FMD）（第0天），以及在最后一次甜菜根汁(BR)剂量后约24小时(第8天,第7天后BR)。因此,在IR损伤后立即测量FMD,并在15分钟后(恢复)测量FMD。
■线性混合效应模型的结果表明，与BR安慰剂相比，服用BRnitrate7天的静息口蹄疫明显增加（平均差异为2.21，95％CI[0.082，4.34]，p=0.042)；然而，两种治疗方法均未缓解绝经后任何一组IR损伤后FMD的下降.我们的结果表明，在最终剂量的硝酸酯后的24小时内，硝酸酯介导的7天内皮保护作用丧失。
■我们的研究结果表明，硝酸盐介导的绝经后内皮保护依赖于补充时间与IR损伤和饮食硝酸盐代谢的时间生物学变化有关。
■https://classic.clinicaltrials.gov/ct2/show/NCT03644472.
