Onion quercetin inhibits vascular endothelial cell dysfunction and prevents hypertension

Onion consumption has been reported to be associated with a lower incidence of myocardial infarction and stroke. Quercetin found in onions may contribute to this effect. This review aimed to describe the role of quercetin in vascular endothelial dysfunction-related hypertension. It also described the effects of quercetin on blood pressure (BP) regulation, vascular endothelial cell health associated with cardiovascular disease (CVD), and possible mechanisms underlying these effects. To this end, several epidemiological, in vivo, and in vitro studies published in PubMed, ScienceDirect, and Web of Science were analyzed. Epidemiological studies have shown that onions and quercetin can lower BP level and improve vascular dysfunction. The antioxidant and anti-inflammatory effects of quercetin may contribute to antihypertensive effect and endothelial cell health. In particular, in vivo studies have demonstrated that quercetin and its metabolites inhibit the renin-angiotensin (RA) system and increase nitric oxide (NO) production, reactive oxygen species production, and vascular endothelial cell inflammation, thereby possibly contributing to the improvement of endothelial dysfunction. Thus, quercetin acts directly on vascular endothelial cells to block hypertension and potentially contributes to CVD prevention.

Automated summary

Onion and quercetin found in onions can lower blood pressure, improve vascular dysfunction, and prevent cardiovascular disease through antioxidant, anti-inflammatory effects, inhibition of the renin-angiotensin system, and increased nitric oxide production.