Overview of 8 Circulating MicroRNAs and Their Functions as Major Biomarkers for Cardiovascular Diseases

Intracellular microRNAs (miRNAs) can be released into extracellular compartments, thus entering into body fluids such as blood circulation. Circulating miRNAs are highly stable and considered as novel biomarkers for the diagnosis and/or prognosis of cardiovascular diseases (CVDs). There is a growing body of evidence supporting circulating miRNAs as prognosis and/or diagnosis biomarkers for CVDs. Using the signatures of circulating miRNAs could improve sensitivity and specificity as biomarkers for CVDs, including unstable angina, myocardial infarction, in-stent restenosis after coronary drug-eluting stents implantation, atrial fibrillation, and heart failure. Circulating miRNAs are associated with other traditional CVD biomarkers such as cardiac-specific troponin, myoglobin and creatine kinase-MB, and other CVD risk factors such as diabetes mellitus and hyperlipidemia. The present review is different with other review articles in that we provide detailed information for individual miRNAs, including both clinical and basic science data. We have selected the 8 miRNAs (miR-1, miR-21, miR-126, miR-133, miR-145, miR-208, miR-223, and miR-499) that are most studied and have shown major clinical value as biomarkers for CADs. The purpose of this review is to provide a full-spectrum overview of these miRNAs and to help clinicians/researchers to understand the clinical value of major circulating miRNAs and help them to design or participate in further investigations of these miRNAs, developing new technologies to improve health care for patients with CVDs.