Circulating microRNA: a novel potential biomarker for early diagnosis of acute myocardial infarction in humans

Eur Heart J. 2010 Mar;31(6):659-66. doi: 10.1093/eurheartj/ehq013. Epub 2010 Feb 16.


Aims: microRNA (miRNA) is reported to be present in the blood of humans and has been increasingly suggested as a biomarker for diseases. We aim to determine the potential of cardiac-specific miRNAs in circulation to serve as biomarkers for acute myocardial infarction (AMI).

Methods and results: By verifying their tissue expression patterns with real-time polymerase chain reaction (PCR) analysis, muscle-enriched miRNAs (miR-1, miR-133a, and miR-499) and cardiac-specific miR-208a were selected as candidates for this study. With miRNA microarray and real-time PCR analyses, miR-1, miR-133a, and miR-499 were present with very low abundance, and miR-208a was absent in the plasma from healthy people. In the AMI rats, the plasma levels of these miRNAs were significantly increased. Especially, miR-208a in plasma was undetected at 0 h, but was significantly increased to a detectable level as early as 1 h after coronary artery occlusion. Further evaluation of the miRNA levels in plasma from AMI patients (n = 33) demonstrated that all four miRNA levels were substantially higher than those from healthy people (n = 30, P < 0.01), patients with non-AMI coronary heart disease (n = 16, P < 0.01), or patients with other cardiovascular diseases (n = 17, P < 0.01). Notably, miR-208a remained undetectable in non-AMI patients, but was easily detected in 90.9% AMI patients and in 100% AMI patients within 4 h of the onset of symptoms. By receiver operating characteristic curve analysis, among the four miRNAs investigated, miR-208a revealed the higher sensitivity and specificity for diagnosing AMI.

Conclusion: Elevated cardiac-specific miR-208a in plasma may be a novel biomarker for early detection of myocardial injury in humans.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Area Under Curve
  • Biomarkers / metabolism
  • Coronary Vessels
  • Disease Models, Animal
  • Early Diagnosis
  • Female
  • Humans
  • Ligation
  • Male
  • MicroRNAs / metabolism*
  • Middle Aged
  • Muscle, Skeletal / metabolism
  • Myocardial Infarction / diagnosis*
  • Myocardium / metabolism
  • Rats
  • Reverse Transcriptase Polymerase Chain Reaction


  • Biomarkers
  • MicroRNAs