Cysteine sulfenylation-selective carbon nucleophiles prevent oxLDL/CD36–mediated platelet aggregation. (A) Structures of the carbon nucleophiles used to selectively target cysteine sulfenylation (Cys-SOH). The red carbon is the site of covalent adduction onto sulfenylated cysteines. (B) Carbon nucleophiles show varying degrees of inhibiting platelet aggregation by oxLDL/CD36. Human platelets (3 × 10⁸/mL) were pretreated with varying concentrations of carbon nucleophiles for 15 minutes prior to stimulation for 15 minutes with 50 µg/mL oxLDL. Platelet aggregation was initiated after 200 µg/mL fibrinogen and 1 mM CaCl₂/MgCl₂ were added. The percentage of maximum platelet aggregation by oxLDL was plotted and the IC₅₀ calculated from fitted curves using log [inhibitor] vs normalized response nonlinear regression. (C) Representative aggregometry tracing of BTD-mediated inhibition of CD36 signaling. Human platelets (3 × 10⁸/mL) were pretreated with DMSO or up to 5 mM BTD, followed by stimulation with 50 µg/mL oxLDL for 15 minutes. Platelet aggregation was initiated after adding 200 µg/mL fibrinogen and 1 mM CaCl₂/MgCl₂. BTD does not inhibit platelet activation by physiologic activators ADP and collagen. (D-E) Human platelets (3 × 10⁸/mL) were pretreated with 1 mM BTD for 15 minutes before aggregation induced by the agonists ADP (2 or 20 µM) (D) or collagen-related peptide (CRP; 1 or 10 µg/mL) (E). P values were determined by 1-way analysis of variance with Dunnett’s post hoc analysis (C) and paired Student t test (D-E). **P < .01 compared with no treatment in (C). N ≥ 3 separate donors (B-C), and N = 3 separate donors (D-E). Data are expressed as mean ± SEM. PRD, 1-methylpiperidine-2,4-dione; PYD, 1-methylpyrrolidine-2,4-dione.