MicroRNAs that Distinguish Neonatal Cardiovascular Progenitor Cells and are Induced during Cardiovascular Repair

SMSU Event Center

Myocardial infarctions affect approximately 735,000 people annually in the United States and decrease quality of life. Damaged adult human heart muscle does not naturally regenerate, however, neonates have an enhanced capability of repairing cardiovascular damage, but the process in which this occurs is unknown. Studies have shown that microRNAs (miRNAs) play a major role in the regenerative ability of cardiac stem cells. The objective of this project is to distinguish alterations in miRNA expression in human neonatal and adult cardiac progenitor cell (CPC) clones expressing islet-1. We hypothesize that transcripts encoding miRNAs associated with enhanced stemness, cell division, and survival will exhibit elevated levels of expression in neonatal CPC. To address this question multiple unique neonatal and adult clonal populations were isolated and analyzed using RT-PCR to assess 41 different miRNA transcript levels. To understand the role of miRNA expression associated with the regenerating myocardium of CPC-mediated cardiovascular repair, total RNA was purified from the CPC-treated region of the myocardium of four sheep, and control sheep. Several miRNAs were induced after neonatal CPC transplantation while also elevated in the human neonatal CPCs when compared to adults. Included in this group of miRNAs is the miRNA-302 family, which is involved in the regulation of stemness and pluripotency. Literature has shown that these miRNAs have the capability of improving cardiovascular function after cardiovascular tissue damage. These studies will facilitate the identification of miRNAs that are involved in cardiovascular repair, providing an avenue to enhance future, stem cell-based clinical therapies.