Inhibitory effects of sulphated flavonoids isolated from Flaveria bidentis on platelet aggregation

GUGLIELMONE HUGO A; AGNESE AM; NUÑEZMONTOYA S; CABRERA JL

PERGAMON-ELSEVIER SCIENCE LTD

Año: 2005 vol. 115 p. 495 - 495

laveria bidentis is a plant species that has as major constituents sulphated flavonoids in the highest degree of sulphatation. Among them, quercetin 3,7,3´,4´-tetrasulphate (QTS) and quercetin 3-acetyl-7,3´,4´-trisulphate (ATS) are the most important constituents. Both showed anticoagulant properties. The objective of the present study was to evaluate the effects of these flavonoids on human platelet aggregation in comparison with the well-known inhibitor quercetin (Qc) by using several agonists. Platelet-rich plasma (PRP) or washed human platelets (WP) were incubated with different concentrations of the flavonoids to be tested (1 to 1000 microM, final concentration), and the platelet aggregation was induced by using adenosine 5´-diphosphate (ADP), epinephrine (EP), collagen, arachidonic acid (AA) and ristocetin as agonists. QTS (500 microM) and Qc (250 microM) markedly inhibited platelet aggregation with all the aggregant agents, except ristocetin, whereas