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.
■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.