Conclusions
These results indicate that curcumin displays selective and potent inhibitory activity on platelet responses to pathological stimuli, such as fibrillar amyloid peptides.
Methods
Commercial ultrapure curcumin was used, and platelet aggregation, granule secretion, phosphorylation of selected signaling proteins, and reactive oxygen species production were analyzed on isolated human platelets.
Results
Our results demonstrate that curcumin effectively suppressed platelet aggregation induced by fibrillar amyloid peptides. This effect was associated with the reduction in intracellular signaling pathways involving PKC, PI3K, and MAPK. By contrast, platelet aggregation and activation induced by thrombin and convulxin were only partially reduced by preincubation with curcumin. Moreover, curcumin completely suppressed granule secretion only when platelets were stimulated with hemostatic agonists, but it had no effects upon stimulation with amyloid peptides. Additionally, curcumin reduced the production of reactive oxygen species induced by amyloid peptides with a stronger efficiency compared to platelets stimulated with thrombin. Conclusions: These results indicate that curcumin displays selective and potent inhibitory activity on platelet responses to pathological stimuli, such as fibrillar amyloid peptides.