Change of plasma microRNA-208 level in acute myocardial infarction patients and its clinical significance

Zhijun Han, Lizhu Zhang, Ling Yuan, Xiaoxiao Liu, Xi Chen, Xinhe Ye, Chengjian Yang, Zihe Yan


Background: To study the change of cardiac-specific microRNA-208 (miRNA-208) level in acute myocardial infarction (AMI) patients and to explore the role of miRNA-208 in AMI progression.
Methods: The consecutive subjects including 42 AMI patients, 22 patients with unstable angina (UA), and 40 healthy subjects in our hospital from January 2013 to December 2013 were enrolled in this study. The peripheral miRNA-208 level was measured with real-time reverse-transcription polymerase chain reaction (RT-PCR), and the plasma cardiac troponin I (cTnI) and creatine kinase-MB (CK-MB) levels were determined using electrogenerated chemiluminescence (ECL) method. Patients in the AMI group were further grouped according to the number of stenosed coronary vessels and primary percutaneous coronary intervention (PCI) or not, and the difference in peripheral miRNA-208 level among these subgroups was analyzed.
Results: The miRNA-208 level was significantly higher in AMI group than in UA group and healthy controls immediately after admission (P<0.01). In the AMI patients, the plasma miRNA-208 level had a positive correlation with serum cTnI level (r=0.700, P=0.000). In 24 AMI patients who had undergone coronary angiography, the expression of miRNA-208 was significantly higher in patients with two or three stenosed coronary vessels. In 17 AMI patients who had successfully received emergent PCI treatment, the 24-h plasma miRNA-208 level was significantly lower than that immediately after admission (P<0.01).
Conclusions: The peripheral plasma miRNA-208 level remarkably increases after cardiac infarction and may dramatically change along with the increase of the myocardial damage. Thus, it may be a new biomarker for AMI.