Anticoagulant effect and action mechanism of sulphated flavonoids from Flaveria bidentis.

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

PERGAMON-ELSEVIER SCIENCE LTD

Año: 2002 vol. 105 p. 183 - 183

uercetin 3-acetyl-7,3´,4´-trisulphate (ATS) and quercetin 3,7,3´,4´-tetrasulphate (QTS) obtained from Flaveria bidentis (Asteraceae) were investigated in vitro for anticoagulant activity. Three different concentrations of each flavonoid were assayed at different incubation times, showing at 1 mM significant prolongation on the activated partial thromboplastin time (APTT), less on the prothrombin time (PT), and no effect on the thrombin time (TT). In order to define the action mechanism of the anticoagulant activity, all coagulation factors were evaluated and no important activity decrease was observed, indicating that another mechanism is involved. Thus, thrombin inhibition mediated by antithrombin III (ATIII) and heparin cofactor II (HCII) activation was investigated in comparison to the physiological activators, heparin and dermatan sulphate (DS), respectively. As a conclusion, no activation on ATIII for neither flavonoids was observed. On the contrary, Q