Within the body, NO is produced by nitric oxide synthases via converting l-arginine to citrulline. Additionally, NO is also produced via the NOS-independent nitrate-nitrite-NO pathway. Unlike the classical pathway, the nitrate-nitrite-NO pathway is oxygen independent and viewed as a back-up function to ensure NO generation during ischaemia/hypoxia. Dietary nitrate and nitrite have emerged as substrates for endogenous NO generation and other bioactive nitrogen oxides with promising protective effects on cardiovascular and metabolic function. In brief, inorganic nitrate and nitrite can decrease blood pressure, protect against ischaemia-reperfusion injury, enhance endothelial function, inhibit platelet aggregation, modulate mitochondrial function and improve features of the metabolic syndrome. However, many questions regarding the specific mechanisms of these protective effects on cardiovascular and metabolic diseases remain unclear. In this review, we focus on nitrate/nitrite bioactivation, as well as the potential mechanisms for nitrate/nitrite-mediated effects on cardiovascular and metabolic diseases. Understanding how dietary nitrate and nitrite induce beneficial effect on cardiovascular and metabolic diseases could open up novel therapeutic opportunities in clinical practice.

中文翻译：

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硝酸盐和亚硝酸盐对心血管和代谢疾病的保护作用机理。

在体内，一氧化氮合酶通过将1-精氨酸转化为瓜氨酸生成NO。此外，还通过非NOS依赖性硝酸盐-亚硝酸盐-NO途径产生NO。与经典途径不同，硝酸盐-亚硝酸盐-NO途径与氧气无关，被视为一种备用功能，可确保在缺血/缺氧时不会产生NO。饮食中的硝酸盐和亚硝酸盐已成为内源性NO生成的底物和其他具有生物活性的氮氧化物，对心血管和代谢功能具有良好的保护作用。简而言之，无机硝酸盐和亚硝酸盐可降低血压，防止缺血再灌注损伤，增强内皮功能，抑制血小板聚集，调节线粒体功能并改善代谢综合征的特征。然而，关于这些对心血管疾病和代谢性疾病的保护作用的具体机制的许多问题仍不清楚。在这篇综述中，我们集中于硝酸盐/亚硝酸盐的生物活化，以及硝酸盐/亚硝酸盐介导的对心血管疾病和代谢疾病的潜在作用机制。了解饮食中的硝酸盐和亚硝酸盐如何对心血管疾病和代谢性疾病产生有益作用，可以为临床实践带来新的治疗机会。