Cardiac-released extracellular vesicles can activate endothelial cells.

In a recent edition of Annals of Translational Medicine , Doran and Voora are giving a commentary entitled “Circulating extracellular vesicles containing miRNAs may have utility as early biomarkers for cardiac injury” (1), a perspective on our recent work on the release of extracellular vesicles (EVs) after myocardial injury (MI) (2). Current standard biomarkers for MI are circulating creatinine Kinase MB (CK­MB) and cardiac troponin, which are released within 2–3 hours after the onset of cardiac injury. Although extremely powerful in a daily clinical setting, a continuous search for new markers is warranted since both an early rule-in or rule-out of MI is associated with improved outcomes and lower health-care costs. A novel direction for new biomarkers is their association with small carriers, including EVs, which are present in human serum and can carry a variety of proteins, RNAs and microRNAs (miRNAs) in higher quantities then free in plasma. Nature is, however, not generating EVs as biomarkers but is using these mediators as powerful signaling molecules to activate and stimulate cells, thereby potentially including reparative signals to induce inflammation or maybe regeneration (3).