We demonstrated the effects of exosomes secreted by cardiac mesenchymal stem cells (C-MSC-Exo) in protecting acute ischemic myocardium from reperfusion injury. To investigate the effect of exosomes from C-MSC on angiogenesis, we injected C-MSC-Exo or PBS intramuscularly into ischemic hind limb. Blood perfusion of limb was evaluated by laser Doppler Imaging. We observed that ischemic limb treated with C-MSC-Exo exhibits improved blood perfusion compared to ischemic limb treated with PBS at 2 weeks and 1 month after induction of limb ischemia. To explore the potential mechanisms underlying C-MSC-Exo's angiogenetic effect, we performed microRNA array analysis and identify mmu-miR-7116-5p as the most abundant enriched miRNA detected in C-MSC-Exo. Bioinformatics' analysis shows that miR-7116-5p negatively regulates protein polyubiquitination. In conclusion, our study demonstrated that intramuscular delivery of C-MSC-Exo after limb ischemia improves blood perfusion, and we identified the most abundant miRNAs that are preferentially enriched in C-MSC-Exo.
Keywords: Angiogenesis; Cardiac mesenchymal stem cells; Exosomes; Hind limb ischemia; miR-7116-5p.