Department of Pharmaceutics, California Northstate University College of Pharmacy, 10811 International Drive, Rancho Cordova, California, USA.
Nutr Rev. 2012 Jun;70(6):367-72. doi: 10.1111/j.1753-4887.2012.00477.x. Epub 2012 Apr 19.
Epidemiological evidence suggests a higher consumption of vegetables confers a protective effect against the risk of cardiovascular disease. Impaired bioavailability of nitric oxide (NO), which is a critical regulator of vascular homeostasis, in the vasculature is thought to be a major problem in cardiovascular disease. Classically, vascular endothelium is suggested to be the sole source of bioactive NO in the vasculature. Emerging literature, however, associates the nitrate-nitrite-NO pathway, in which endogenous nitrate undergoes reduction to nitrite and then to NO in various tissues, including blood, with the production of bioactive NO. Indeed, NO generated from the nitrate-nitrite-NO pathway has recently been associated with the maintenance of NO homeostasis in the body. Endogenous nitrate originates mostly from NO oxidation in the biological milieu and from exposure to dietary nitrate. Consumption of vegetables accounts for approximately 80-85% of daily nitrate exposure in humans, thereby establishing inorganic nitrate as a promising factor in the cardiovascular health benefits of vegetables. At this point in time, however, the benefit : hazard ratio of inorganic nitrate and its active metabolite nitrite remains less clear and must be studied in prospective controlled studies. This brief review discusses the potential role of inorganic dietary nitrate in the cardiovascular health benefits of vegetables.
流行病学证据表明，蔬菜摄入量较高可降低心血管疾病的风险。血管中一氧化氮（NO）的生物利用度受损，被认为是心血管疾病的一个主要问题，而 NO 是血管稳态的关键调节剂。传统上，血管内皮被认为是血管中生物活性 NO 的唯一来源。然而，新出现的文献将硝酸盐-亚硝酸盐-NO 途径与内源性硝酸盐在包括血液在内的各种组织中还原为亚硝酸盐，然后再还原为 NO 联系起来，与生物活性 NO 的产生有关。事实上，最近已经有研究表明，来自硝酸盐-亚硝酸盐-NO 途径的 NO 与体内 NO 稳态的维持有关。内源性硝酸盐主要来源于生物环境中 NO 的氧化和饮食中硝酸盐的暴露。蔬菜的摄入约占人体每日硝酸盐暴露量的 80-85%，从而使无机硝酸盐成为蔬菜对心血管健康有益的一个有希望的因素。然而，在现阶段，无机硝酸盐及其活性代谢物亚硝酸盐的益处与危害比仍不明确，必须在前瞻性对照研究中进行研究。这篇简要综述讨论了无机饮食硝酸盐在蔬菜对心血管健康益处中的潜在作用。
