Antioxidants with carcinostatic activity (resveratrol, vitamin E and selenium) in modulation of blood platelet adhesion

Compounds with potential antiplatelet activity can be used in the therapy o f cardiovascular disorders. We investigated the effects of three different antioxidants with carcinostatic property: trans-resveratrol, Trolox - a wat er-soluble analog of vitamin E, and inorganic selenocompounds (sodium selen ite and selenate) on blood platelet adhesion to fibrinogen (Fg). Adhesion, the initial step of platelet activation, was estimated by the colorimetric method with BCA (bicinchoninic acid) solution in 96-well Fg-coated microtit er dishes. It was shown that resveratrol significantly inhibited adhesion o f both thrombin- and ADP-activated platelets to Fg. After incubation of pla telets for 30 min. at 37 degrees C with resveratrol at the concentration of 100 mu g/ml above 40% inhibition of adhesion was achieved. The inhibition of platelet adhesion of Fg caused by Trolox was lower than by resveratrol a nd at higher concentration (1 mM) reached maximum 12%. We also demonstrated that neither sodium selenite nor selenate significantly altered platelet a dhesion to Fg. We conclude that changed adhesion of blood platelets to Fg i n the presence of resveratrol and Trolox, but not selenium may be the resul t of different antioxidative activities of tested compounds.