Abstract 21308: Mesenchymal Stem Cells Driven by Exosomal Mir-125b Protect Myocardial Infarction via P53-Mediated Autophagy Signalling

Background and Objectives: Bone marrow derived mesenchymal stem cells (MSCs) transplantation confers protection against adverse cardiac remodeling mainly through paracrine effects, however, it remains largely unknow whether autophagy is involved in the protection offered by MSCs therapy. In the present study, we used the mice myocardial infarction(MI)model to investigate whether and how MSCs modulates autophagy activity to protect the injured myocardium. Methods and Results: Using a well established methodology of MSCs therapy for treating myocardial infarction, we reproduced the data that MSCs can reduce myocardial apoptosis to improve cardiac function post-MI, which was closely associated with attenuated autophagy flux in cardiac tissue. To further investigate how MSCs modulate autophagic activity, we co-cultured MSCs with neonatal mice cardiomyocytes (NMCMs) to test whether NMCMs co-cultured with MSCs exhibited enhanced tolerance to hypoxia. We showed that NMCMs exposed to hypoxia had increased autopha...