Abstract 16314: Identification of MicroRNAs Inducing Adult Cardiomyocyte Proliferation

Background: Even though neonatal cardiomyocytes (NCM) proliferate robustly, adult cardiomyocytes (ACM) have very little proliferative potential. By functional screening of 875 microRNAs (miRs) Eulalio et al 2012 identified 46 miRs which induce proliferation of NCMs by more than 35%. Additional studies by Mahmood et al 2013 have identified Meis1 as the major player that controls ACM cell cycle. We hypothesize that the proliferation inducing potential of miRs may vary between NCMs and ACMs and some of these miRs may induce proliferation through Meis1 regulation. Methods and Results: ACM were isolated from male rats aged 4-6 months and transfected with miR mimics for cel-67 (control) and 24 of the top NCM proliferation inducing miRs individually. Edu was administered for 4 days starting day 1 after transfection. Cells were fixed on day 5 and immuno-stained. Proliferating cardiomyocytes were identified by co-staining of TnI and Edu and the percentage was calculated in each group. Eighteen of the 24 miRs induc...