Effects of 3,5,4′-tri-[4-(nitrooxy)butanoyl]oxy resveratrol, a new nitric oxide-releasing derivative of resveratrol, on platelet activation

Background Resveratrol is a polyphenol of red wine that is thought to contribute to the "French paradox" by protecting against atherosclerotic cardiovascular events. It has anti-inflammatory and antioxidant properties and enhances nitric oxide (NO) production. However, in conditions of severe endothelial dysfunction, its cardiovascular protective effects may be limited. Our study aimed to synthesize and characterize a new nitro derivative of resveratrol, trinitroresveratrol (TN-RSV), for its potential nitric oxide-donating and antiplatelet effects. Methods 3,5,4′-tri-[4-(nitrooxy)butanoyl]oxy resveratrol (TN-RSV) was synthetized starting from commercial resveratrol (RSV) through the intermediacy of 3,5,4′-tri-(4-bromo-butanoyl)oxy resveratrol. Platelet aggregation was assessed by light transmission aggregometry (LTA) using collagen as agonist. The release of nitric oxide (NO) from TN-RSV or from activated platelets was assessed as the concentration of the NO degradation products (nitrites plus nitrates, NOx) in the supernatant. Platelet adhesion to collagen under flow conditions was assessed using a parallel plate perfusion chamber. Reactive oxygen species (ROS) production from collagen-activated platelets was assessed by flow cytometry using the fluorescent probe H2DCFDA. Results TN-RSV spontaneously released NO and significantly inhibited collagen-induced platelet aggregation in a dosedependent manner. This effect was greater than that of resveratrol and it was not affected by the preincubation with L-NAME, a nitric-oxide synthase (NOS) inhibitor, indicating that TN-RSV directly inhibits platelet activation independently of NOS. Conclusions Our findings suggest that TN-RSV has potential as an antiplatelet agent and that further research exploring its therapeutic applications for conditions associated with endothelial dysfunction and platelet hyperreactivity is warranted.