EDN1 and endothelial dysfunction: Three quercetin metabolites, i.e., quercetin-3-glucuronide, isorhamnetin-3-glucuronide and quercetin-3’-sulfate have been shown to prevent the impairment of endothelial-derived NO response while only quercetin and quercetin-3-glucuronide are able to prevent the in vitro ET-1 induced endothelial dysfunction.