Abstract

To examine the effect of cell transplantation and gene therapy on myocardial infarction. In this project, the mesenchymal stem cells (MSCs) exposed to ⁶⁰Co γ irradiation were transplanted into SD rats. MSCs were divided into two groups: control and irradiation groups. The control group did not receive irradiation. Irradiation group received irradiation. Different irradiation doses can have opposite effects on cell proliferation: irradiation dose as low as 2 to 4 Gy did not markedly affect MSCs growth, whereas higher doses of irradiation killed MSCs. There was clear mRNA amplification for C-TNT (IOD 0.36) and β-MHC (IOD 0.21) in cultured cells of group 1. The expression of mRNA for C-TNT and β-MHC could not be detected in cells of group 2 at week 4. After cell transplantation operation, left ventricular end-diastolic diameter (LVDd) of animals reduced and left ventricular ejection fraction (LVEF) increased. There was higher Left Ventricular End-Diastolic Pressure (LVEDP) in groups A and E than that in groups B, C and D. In addition, cardiac systolic and diastolic functions all markedly decreased. The expression of cytokines vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF) and interleukin-1β (IL-1β) mRNA was markedly increased in myocardial tissue of group B, C and D. But expression of cytokines VEGF, bFGF and IL-1β mRNA was not detected in myocardial tissue of groups A and E. MSCs transplantation was useful for myocardial infarction.

Key words: ⁶⁰Co γ irradiation, MSCs, myocardial infarction.