Abstract：[Abstract]Objective: To investigate the repair effect of exosome derived from human umbilical cord mesenchymal stem cells(hucMSCexosome) to ischemia/reperfusion (I/R) myocardial cells. Methods: In vivo, Female SpragueDawley rats′ left anterior descending coronary artery (LAD) was occluded to induce regional myocardial ischemia, reperfusion was achieved by releasing the clamp. After 30 min of ischemia, hucMSCexosome was injected via tail vein. In vitro, I/R of H9C2(21) rat embryonic cardiac myoblasts was achieved by culturing the cells in low glucose DMEM without FBS in a hypoxia chamber, saturated with 5%CO2/93%N2 for 24 h and following reoxygenation using 10%FBS high glucose DMEM and hucMSCexosome in the normal incubating condition for 24 h. Using MTT, TUNEL, myocardial enzyme spectrum and mitochondrial membrane potential and other methods to detect the proliferation and apoptosis of myocardial cell. Results: In vivo,after the injury of I/R,lower level of LDH and CK activity was observed in the hucMSCexosome or hucMSC pretreated cells as compared with PBS control cells. TUNEL staining showed that there was a decrease in apoptosis in the injured cells after pretreated with hucMSCexosomes or hucMSC compared to PBStreated group. In vitro, cell proliferation examined by MTT assay were shown to reduce significantly after the injury of H/R. Pretreatment of cells with hucMSCexosome resulted in a marked decrease in hucMSCexosome induced mitochondrial membrane potential(ΔΨm) and apoptosis. Conclusion: Exosome secreted by hucMSC can reduce the injury of myocardial I/R effectively.
2012, Vol. 22 
