Abstract

Xiaohui Ma*, Wei Guo, Xiaoping Liu, Tai Yin, Xin Jia, Jiang Xiong, Hongpeng Zhang and Lijun Wang

Mesenchymal stem cells (MSCs) are undifferentiated multipotent cells which reside in various human tissues and have the potential to differentiate into osteoblasts, chondrocytes, adipocytes, fibroblasts and other tissues of mesenchymal origin. In this study, we investigated the effect of 60Co radiation on the proliferation and differentiation of MSCs. MSCs were treated with increasing radiation doses to assess the effect on MSC. Results showed that 2 Gy of 60Co radiation did not significantly affect MSCs. When compared with the control group and 2Gy of 60Co radiation group, the MSCs viability after 4 Gy of 60Co radiation markedly decreased (p < 0.05). Two weeks of 8 and 12 Gy of 60Co radiation induced all cell death. After the 5-Aza treatment, the expression of myocardial- specific protein, C-TNT and -MHC was not detected in the MSCs which were pretreated by 60Co radiation. In conclusion, middle dose (4 Gy) of irradiation induces MSCs morphological changes, as well as alteration in both proliferation and differentiation potentials of MSCs. 5- Aza treatment did not induce both proliferation and differentiation of MSCs because high dose (8 and 12 Gy) of irradiation killed all cells.