MicroRNAs in platelet function and cardiovascular disease.

Cardiovascular disease--a leading cause of morbidity and mortality among adults-is strongly influenced by platelet function through acute thrombotic and atherogenic mechanisms. Pathways that regulate platelet activity and lead to coronary occlusion are central to the pathogenesis of acute coronary syndromes. Platelet activation contributes to other thrombotic disorders and cardiovascular diseases, including stroke. Anucleate platelets are now understood to contain transcripts that might relate to other physiological or pathophysiological conditions, be released into the circulation, participate in protein formation, and engage in horizontal RNA transfer to other vascular cells. These platelet transcripts include microRNAs (miRNAs), which are small noncoding RNAs involved in many molecular processes, most notably regulation of gene expression. In platelets, these noncoding RNAs seem to participate in vascular homeostasis, inflammation, and platelet function. In addition, levels of platelet miRNAs in the circulation are associated with the presence or extent of cardiovascular diseases, such as atrial fibrillation and peripheral vascular disease. Accumulating data suggest mechanistic roles for platelet-derived miRNAs in haemostasis, thrombosis, and unstable coronary syndromes. In addition, evidence suggests that platelet-derived miRNAs might have important roles as biomarkers of cardiovascular disease susceptibility, prognosis, or treatment.