Figure 1.

(A) The molecular structure of eugenol, with the molecular formula C₁₀H₁₂O₂, is illustrated. Washed human platelets (3.6 × 10⁸ cells/mL) were preincubated with either a solvent control (0.1% DMSO) or varying concentrations of eugenol (0.5 to 100 μM). Subsequently, platelets were exposed to different agonists, including (B) collagen (1 μg/mL), (C) arachidonic acid (AA; 60 μM), (D) thrombin (0.02 U/mL), or (E) U46619 (1 μM), to induce platelet aggregation. Concentration-response histograms for eugenol highlight its inhibitory effects on platelet aggregation triggered by various agonists (%). (F) Cytotoxicity assessment involved preincubating platelets with 0.1% DMSO, 10 μM, or 20 μM eugenol for 10 min, followed by two washes with Tyrode’s solution. Subsequently, platelets were stimulated with collagen (1 μg/mL). Statistical significance levels of * p < 0.05 and *** p < 0.001 indicate differences compared to the 0.1% DMSO-treated group. The presented data in (B–F) represent the mean ± standard error of the mean (n = 4).