Illicit drug N-ethylpentylone potentiates platelet activation through 5-hydroxytryptamine2A receptor-mediated...

Several illicit drugs have been reported to be associated with ischemic stroke and myocardial infarction. However, their underlying mechanisms remain poorly investigated.

In this study, we focused on N-ethylpentylone (NEP), a synthetic cathinone with potent hallucinogenic properties, and explored its role in platelet activation.

Platelet function assays and flow cytometry were used to evaluate the effects of NEP on platelet aggregation, spreading, clot retraction, and integrin α_IIbβ₃ activation. The role of 5-hydroxytryptamine2A receptor (5-HT2AR) in NEP-mediated platelet responses was investigated using the selective 5-HT2AR antagonist M100907 in both ex vivo and in vivo experiments. Phosphoproteomics identified NEP-regulated phosphorylation sites, and Western blotting validated mitogen-activated protein kinase pathway activation by targeting key phosphorylation nodes.

NEP significantly potentiated platelet aggregation, spreading, clot retraction, and integrin α_IIbβ₃ activation in a concentration-dependent manner. The NEP-potentiated platelet responses were suppressed by M100907 in both ex vivo and in vivo models, confirming the critical regulatory role of 5-HT2AR. Phosphoproteomics revealed NEP-triggered upregulation of phosphorylation, which was enriched in mitogen-activated protein kinase pathways. Western blotting confirmed selective extracellular signal-regulated kinase and p38 phosphorylation, with no effect on C-Jun NH2-terminal kinase.

NEP directly enhances agonist-induced platelet activation by targeting 5-HT2AR on platelet membranes. The findings of this study provide valuable insights for elucidating the hematotoxic mechanisms of NEP and other illicit drugs.