Abstract 16332: MicroRNA Mediated Proliferation of Human iPS Derived Cardiomyocytes for Cardiac Repair
Background: An innovative approach to generate cells for cardiac regeneration is to reprogram somatic cells into iPS and differentiate them into cardiomyocytes (CMs). Recent studies have shown micro-RNAs (miRs) can induce proliferation of neonatal rat and mouse cardiomyocytes. Here we report that overexpression of specific miRs can induce proliferation of human iPS (HiPS) derived CM and improve cardiac regeneration and function.
Methods and Results: Studies by Eulalio et. al, in 2012 identified a list of miRs that induced proliferation in neonatal mammalian cardiomyocytes. Here we transiently transfected human iPS derived CMs with miR-cel-67 (control miR), miR-1273, miR-210, and miR-1825 and administered EDU (5μM) to label proliferating cells. Five days post transfection, cells were fixed and stained for cardiomyocytes marker troponin-I, and EDU. A significant increase in proliferation was observed with miR-210 and miR-1825, while miR-1273 did not show any significant change (21.03 % and 42.97% with miR-210 and miR-1825, respectively as compared to 7.2% with miR-1273 and 6.9% with control miR-cel-67; p<.05). We selected miR-1825 for in-vivo cell transplantation experiments using immunocompromised nude mice (NOD.CB17-Prkdcscid/J). HiPS CMs were transfected with either control miR-cel-67 or miR-1825 and transplanted in mice hearts following LAD ligation. Cell control group received DMEM without cells (N= 8/group). EDU was administered IP at a concentration of 500μg/100μl per mouse, every alternate day, up to day 12 after transplantation. Four weeks after LAD ligation hearts were harvested for immuno-histology studies. Both the cell transplanted groups showed a significant reduction in infarction size when compared to DMEM control group (DMEM control 48.75+/- 5.6% vs miR-1825 HiPS CMs 33.86 +/- 4.0%; p<.05).
Conclusion: We here show a significant increase in proliferation of HiPS CMs following miR-210 and miR-1825 transduction. Our in-vivo studies show a reduction in infarction size in mice hearts that were transplanted with HiPS CMs compared to DMEM control. Collectively, this study proposes a novel approach of transplanting proliferating HiPS-CMs to acheive cardiac regeneration following ischemic injury.
Author Disclosures: S. Durrani: None. R. Pandey: None. S. Jiang: None. R.P. Ahmed: None.
- © 2014 by American Heart Association, Inc.