Abstract 10668: Release Kinetics of Muscle-enriched MicroRNAs in Patients With Acute Myocardial Infarction
Background: MicroRNAs (miRs) have been proposed as novel biomarkers in patients with cardiovascular disease. Data are lacking on the exact release kinetics of miRs in patients with acute myocardial infarction (MI). Therefore, in the present study we aimed to analyze the release kinetics of muscle-enriched (miR-1, miR-208a, miR-133a) miRs in patients with hypertrophic obstructive cardiomyopathy (HOCM) undergoing transcoronary ablation of septal hypertrophy (TASH) as a method uniquely offering a clearly defined onset of myocardial infarction.
Methods and Results: Consecutive patients (n=11) with hypertrophic obstructive cardiomyopathy (HOCM) undergoing TASH were included into the study. TASH was performed according to standard clinical practice. Circulating miRs (miR-1, miR-208a, miR-133a) were measured by TaqMan polymerase chain reaction in serum. Serum samples were collected before as well as 15 min, 30 min, 45 min, 60 min, 75 min, 90 min, 105 min, 2 hours, 4 hours, 8 hours and 24 hours after TASH. Circulating levels of miR-1 increased significantly at 60 min (>30 fold; P=0.02) with a peak after 480 min. MiR-208a level were significantly increased at 75 min (= 2 fold; P=0.03) with a further increase until 105 min after induction of MI (4 fold; P<0.03) and a decrease after 24 hours (<0.5 fold; P=n.s.). Levels of miR-133a were significantly increased already after 45 minutes (16 fold; P=0.03). MiR-133a reached a plateau between 75 min and 480min (50 fold change) and decreases afterwards reaching a fold change of 40 compared to baseline levels after 24 hours.
Conclusion: Muscle-enriched miR-1, miR-208a and miR-133a show a continuous rise during the first 4 hours after onset of myocardial infarction. The first significant difference compared to baseline levels occurs by measuring miR-133a already 45 min after induction of myocardial infarction. These results demonstrate for the first time the regulation of human muscle-enriched miR and provide thereby important information for the use as cardiac biomarkers.
- © 2012 by American Heart Association, Inc.