MicroRNA microarray expression profiling in human myocardial infarction.

MicroRNAs (miRNAs), small non-coding RNA molecules, are negative regulators of gene expression. Recent studies have indicated their role in various forms of cardiovascular disease. In spite of the number of miRNA microarray analyses performed, little is known about the genome-wide miRNA expression pattern in human myocardial infarction (MI).Using miRNA microarrays and bioinformatic analysis, miRNA expression was analyzed on human MI and foetal hearts compared to healthy adult hearts, to determine whether there is any similar expression pattern between MI and foetal hearts, and to identified miRNAs that have not previously been described as dysregulated in cardiovascular diseases. Of 719 miRNAs analyzed, approximately 50% were expressed in human hearts, 77 miRNAs were absent from all tested tissues and 57 were confidently dysregulated in at least one tested group. Some expression patterns appeared to be similar in MI and foetal hearts. Bioinformatic analysis revealed 10 miRNAs as dysregulated in MI not yet related to cardiovascular disease, and 5 miRNAs previously described only in animal models of cardiovascular diseases. Finally, qRT-PCR analysis confirmed dysregulation of 7 miRNAs, miR-150, miR-186, miR-210, miR-451, and muscle-specific, miR-1 and miR-133a/b; all of these are believed to be involved in various physiological and pathological processes.