The Regenerative Effect of Bone Marrow-Derived Stem Cells on Cell Count and Survival in Acute Radiation Syndrome

Acute radiation syndrome (ARS) is called as radiation sickness or radiation toxicity caused by abnormally high exposure to ionizing radiation in a very short period of time.1 High doses of ionizing radiation are able to contribute to detrimental systemic effects in different organs.2 In treatment of patients with ARS, physicians have used growth factors, cytokines and bone marrow transplantation.3 Mesenchymal stem cells (MSCs) have the potential for multilineage differentiation.4,5 Bone marrowderived stem cells (BMSCs) are the most wellknown type of the mesenchymal stem cells used with safety and efficacy in several diseases such as ARS.1 The present study assessed the regenerative effect of bone marrow-derived stem cells on cell count and survival in Acute Radiation Syndrome. For MSC culture, both femoral and tibial bones from male mice were removed and after removal of muscular and connective tissues, the bones were cut at both ends and the bone marrow was flushed out into a 15 ml falcon tube filled with Dulbecco’s Modified Eagle Medium (DMEM; Biovet, Bulgaria) and 1% penicillin streptomycin (Sigma, USA) and centrifuged at 1200 rpm for 5 minutes. The precipitate was cultured in 25 cm2 flasks containing DMEM supplemented with 10% fetal bovine serum (FBS; Biovet, Bulgaria), 1% L-glutamine (Sigma, USA) and 1% penicillin and streptomycin. The culture flasks were transferred into CO2 incubator while the medium was changed every 3 days. The adherent cells were subcultured until passage 5 while they were counted for survival rate. The osteogenic was evaluated with Alizarin Red staining (Sigma, USA). RT-PCR was conducted to evaluate the expression of MSC markers. Forty 8-12 weeks male mice were randomly divided into 2 equal groups. Group A received no BMSCs but group B underwent 150×103 cells of passage 5 in 150 μl medium of BMSC transplantation intravenously into the tail, 24 hours after γ irradiation. Both groups were irradiated with 10 Gy (dose rate .286 Gy/ min) 60CO, during 35 minutes with a field size of 35×35 for all the body area. BMSCs were plastic adherent and spindle-shape (Figure 1) and expressed CD90 marker but not CD34 and CD45 (Figure 2). Culture of BMSCs in osteogenic media lead to osteogenic differentiation of these cells (Figure 3). A significant increase was noticed for the number cells in bone marrow in group B 1. Department of Radiology and Radiotherapy, School of paramedical, Shahid Beheshti University of Medical Science, Tehran, Iran; 2. Stem Cell and Transgenic Technology Research Center, Shiraz University of Medical Sciences, Shiraz, Iran; 3. Department of Surgery, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran; 4. Department of Radiotherapy, Nemazee Hospital, Shiraz University of Medical Sciences, Shiraz, Iran; 5. Department of Biostatistics, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran; 6. Ionizing and Non-Ionizing Radiation Protection Research Center, Shiraz University of Medical Sciences, Shiraz, Iran