title: Effects of quercetin on the release of endothelin, prostacyclin and tissue plasminogen activator from human endothelial cells in culture.
abstract: Quercetin and related flavonoids are naturally occurring polyphenolic compounds with multiple pharmacological activities. Using cultured human umbilical vein endothelial cells, we investigated the effects of quercetin on endothelin (ET-1) and tissue plasminogen activator (t-PA) release induced by thrombin. We observed that when endothelial cells pretreated with 5 or 50 microM of quercetin were incubated for 4 and 24 h with thrombin, ET-1 concentration-dependently decreased (n = 6, P < 0.01, at 4 h IC50 = 1.54 microM, at 24 h IC50 = 2.78 microM). Under the same experimental conditions, quercetin significantly increased t-PA (n = 6, P < 0.01, at 4 h EC50 = 0.71 microM and at 24 hrs EC50 = 0.74 microM). In the same preparation, we evaluated prostacyclin (PGI2) release, induced by thrombin activated platelets, as determined by a 6-Keto-PGF1alpha radioimmunoassay. Following the treatment of cultured endothelial cells with activated platelets, the concentration of 6-Keto-PGF1alpha was significantly increased (P < 0.01). Quercetin (1, 5, and 20 microM) inhibited PGI2, in a concentration-dependent manner (n = 6, P < 0.05). Our data indicate that quercetin modulates the release of ET-1, t-PA, and PGI2 from vascular endothelial cells.
authors.affiliation: Department of Pharmacology, Suzhou Medical College, China.
authors.forename: X
authors.initials: X
authors.lastname: Zhao
authors.forename: Z
authors.initials: Z
authors.lastname: Gu
authors.forename: A S
authors.initials: AS
authors.lastname: Attele
authors.forename: C S
authors.initials: CS
authors.lastname: Yuan
mesh_terms: D015121:6-Ketoprostaglandin F1 alpha / Q000378:metabolism*; D002478:Cells, Cultured; D019332:Endothelin-1 / Q000378:metabolism*; D004730:Endothelium, Vascular / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D006801:Humans; D015539:Platelet Activation / Q000187:drug effects; D011794:Quercetin / Q000494:pharmacology*; D013917:Thrombin / Q000494:pharmacology; D010959:Tissue Plasminogen Activator / Q000378:metabolism*
chemical_list: D019332:Endothelin-1; D015121:6-Ketoprostaglandin F1 alpha; D011794:Quercetin; D013917:Thrombin; D010959:Tissue Plasminogen Activator