Departamento de Clínica Médica - Universidade do Estado do Rio de Janeiro (UERJ), Rio de Janeiro, RJ - Brasil.
Instituto de Química - Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ - Brasil.
Arq Bras Cardiol. 2023 Jan 9;120(1):e20220209. doi: 10.36660/abc.20220209. eCollection 2023.
The diet's inorganic nitrate (NO3-) may provide a physiological substrate for reducing nitrate (NO2-) to NO independent of the endothelium. Studies suggest that inorganic NO3- has beneficial effects on cardiovascular health.
This study evaluated the acute effects of 500 mL nitrate-rich beetroot juice (BRJ; containing 11.5mmol NO3-) on blood pressure and endothelial function in treated hypertensive patients.
A randomized, placebo-controlled, crossover study was conducted in treated hypertensive patients (n=37; women=62%) who underwent clinical and nutritional evaluation and assessment of central hemodynamic parameters and microvascular reactivity. The significance level was p<0.05.
The mean age was 59±7 years, and mean systolic and diastolic blood pressures were 142±10/83±9mmHg. There was a significant increase in the subendocardial viability ratio (SEVR; 149±25 vs. 165±30%, p<0.001) and reduction in ejection duration (ED; 37±4 vs. 34±4%, p<0.001) in the beetroot phase but no significant SEVR difference in the control phase. The % increase in perfusion (155 vs. 159 %, p=0.042) was significantly increased in the beetroot phase, which was not observed in the control phase. In the beetroot phase, the change in SEVR showed a significant correlation with the change in the area under the curve of post-occlusive reactive hyperemia (AUC-PORH) (r=0.45, p=0.012). The change in ED showed a significant correlation with the post-intervention perfusion peak (r=-0.37, p=0.031) and AUC-PORH (r=-0.36, p=0.046).
The acute ingestion of BRJ by hypertensive patients resulted in an improvement of endothelial function, which was associated with higher subendocardial viability and performance in myocardial contraction.
饮食中的无机硝酸盐（NO3-）可能为将硝酸盐（NO2-）还原为非内皮依赖性的 NO 提供生理底物。研究表明，无机 NO3- 对心血管健康有益。
本研究评估了富含硝酸盐的甜菜根汁（BRJ；含有 11.5mmol NO3-）500mL 对治疗高血压患者的血压和内皮功能的急性影响。
在接受治疗的高血压患者（n=37；女性占 62%）中进行了一项随机、安慰剂对照、交叉研究，这些患者接受了临床和营养评估以及中心血液动力学参数和微血管反应性的评估。显著性水平为 p<0.05。
平均年龄为 59±7 岁，平均收缩压和舒张压分别为 142±10/83±9mmHg。在甜菜根阶段，心内膜下存活比（SEVR；149±25 对 165±30%，p<0.001）显著增加，射血时间（ED；37±4 对 34±4%，p<0.001）减少，但在对照阶段 SEVR 无显著差异。在甜菜根阶段，灌注的增加百分比（155 对 159%，p=0.042）显著增加，而在对照阶段则没有观察到。在甜菜根阶段，SEVR 的变化与阻塞后反应性充血的曲线下面积（AUC-PORH）的变化呈显著相关性（r=0.45，p=0.012）。ED 的变化与干预后灌注峰值呈显著相关性（r=-0.37，p=0.031）和 AUC-PORH（r=-0.36，p=0.046）。
高血压患者急性摄入 BRJ 可改善内皮功能，这与更高的心内膜下存活率和心肌收缩功能有关。
