Eleven chalcone derivatives have been tested for their inhibitory effects on platelet aggregation in rabbit platelet suspension and the activation of mast cells and neutrophils.
Arachidonic acid-induced platelet aggregation was potently inhibited by almost all the compounds and some also had a potent inhibitory effect on collagen-induced platelet aggregation and cyclooxygenase. Some hydroxychalcone derivatives showed strong inhibitory effects on the release of β-glucuronidase and lysozyme, and on superoxide formation by rat neutrophils stimulated with the peptide fMet-Leu-Phe (fMLP). We found that the anti-inflammatory effect of 2′,5′-dihydroxychalcone was greater than that of trifluoperazine. 2′,5′-Dihydroxy and 2′,3,4,4′-tetrahydroxyl chalcones, even at low concentration (50 μm), tested in platelet-rich plasma from man almost completely inhibited secondary aggregation induced by adrenaline.
These results suggest that the anti-platelet effects of the chalcones are mainly a result of inhibition of thromboxane formation.