Flavonoids: Antiplatelet Effect as Inhibitors of COX-1

Abstract

Flavonoids are compounds with a benzopyranic structure that exhibits multiple pharmacological activities. They are known for their venotonic activity, but their mechanism of action remains unclear. It is thought that, as this mechanism is mediated by prostaglandins, these compounds may interfere with the arachidonic acid (AA) cascade. These assays are designed to measure the antiplatelet aggregation capacity of quercetin, rutin, diosmetin, diosmin, and hidrosmin, as well as to evaluate a potential structure−activity ratio. In this paper, several studies on platelet aggregation at different concentrations (from 0.33 mM to 1.5 mM) of different flavone compounds are conducted, measuring platelet aggregation by impedance aggregometry, and the cyclooxygenase (COX) activity by metabolites generated, including the activity of the pure recombinant enzyme in the presence of these polyphenols. The results obtained showed that quercetin and diosmetin aglycones have a greater antiplatelet effect and inhibit the COX enzyme activity to a greater extent than their heterosides; however, the fact that greater inhibition of the pure recombinant enzyme was achieved by heterosides suggests that these compounds may have difficulty in crossing biological membranes. In any case, in view of the results obtained, it can be concluded that flavonoids could be useful as coadjuvants in the treatment of cardiovascular pathologies.

Antioxidant Potential of Diosmin and Diosmetin against Oxidative Stress in Endothelial Cells

“…Our findings demonstrate a protective effect of diosmin/diosmetin on H 2 O 2 -induced cell damage in the endothelium; however, it should be pointed out that diosmetin acted more effectively, probably as a result of partial blocking of the activity of diosmin by the sugar moiety. The higher activity of the aglycone form was also observed by Zaragozá et al, who investigated the inhibition of platelet aggregation and COX-1 [ 37 ] and the impact of these flavonoids on the level of pro-inflammatory factors in LPS-treated cells [ 38 ].…”

Post-operative epidural haematoma as complication of overconsumption of dried fruit in lumbar spinal surgery: a case report and review of the literature

“…Primary haemostasis, the initial pathway to form a platelet plug, is dependent on adequate platelet adhesion, activation and aggregation [22]. Flavonoids have been shown to inhibit platelets in a dose-dependent manner [8,11]. It has been reported that a set of 30 different flavonoids inhibit platelet aggregation at concentrations between 0.12 and 122.0 µmol/L [8].…”

“…In addition to PMQ, pycnogenol, catechin and epicatechin, all flavonoid constituents, have been shown to increase the activated partial thromboplastin time (aPTT) and PT, leading to anticoagulation defects [6,9,10]. It seems that flavonoids inhibit platelets in a dose-dependent manner, by altering arachidonic acid metabolism [6,11]. Current research has been unable to quantify the minimum dose or concentration to cause significant clotting abnormalities.…”

Roles of Embryonic Lethal Abnormal Vision-Like RNA Binding Proteins in Cancer and Beyond

“…For example, eltrombopag often acts as a thrombopoietin (TPO) receptor agonist ( Bussel et al, 2019 ), AZA as a DNA methyltransferase inhibitor ( Song et al, 2022 ) and TSA as a histone deacetylase inhibitor ( He et al, 2022 ). Pyrvinium pamoate ( Faheem et al, 2022 ), Rottlerin ( Hufnagel et al, 2009 ), dihydrotanshinone-I ( Sun et al, 2022 ), quercetin ( Zaragozá et al, 2022 ) and suramin ( Zhang et al, 2022 ) all have effects on other physiological or pathological processes.…”