Abstract 18834: Genetic Ablation of S-nitrosoglutathione Reductase (GSNOR) in Mice Enhances Proliferative Expansion of Adult Heart Progenitors and Myocytes Post Myocardial Infarction

Introduction: The molecular pathways underlying the proliferative activity of adult cardiac myocytes and stem/progenitors in response to heart damage remain elusive. Since perturbing nitroso-redox balance in mice by genetic deletion of GSNOR (GSNOR-/-) confers resilience to experimental myocardial infarction (MI), we investigated whether GSNOR knockout influences the proliferative activity of the post-MI heart. Hypothesis: Knockout of GSNOR in mice enhances the proliferative expansion of CMs and cKit+ cardiac stem cells (CSCs) in response to MI. Methods: Wild-type (WT) and GSNOR-/-mice (n=5/ group) underwent experimental MI. To assess proliferative activity, animals received intraperitoneal injections of 5-bromodeoxyuridine (BrdU) at selected time-points during the first 2 weeks post-MI. Immunnohistochemical evaluation was performed 1 month post-MI. Results: Confocal immunofluorescence revealed that GSNOR-/- hearts exhibited higher rates of BrdU incorporation in CSCs after MI (10.9%±4.99 of WT CSCs compar...