Studies Of The Protective Effect Of MgSO₄ On The Radiation-induced Neural Stem Cell Of Rats Injury

Object : to explore the neuroprotective effect of magnesium sulfate on radiation-induced neural stem cells of rats injury.Methods: Brain tissue was obtained from newborn sprague-dawley rats cerebral hemisphere within 24 hours ,dissociate hemisphere to culture the neural stem cells. After the identification of neural stem cell by immunofluorescence, the neural stem cells were randomly divided into 3 groups: blank control group, experimental control group and experimental group. The whole neural stem cells of experimental control group and experimental group were irradiated to a dose of 2Gy or 4Gy with ⁶⁰Co gamma rays .The proliferation ,the apoptosis, the cycle of neural stem cells were detected at different time points ranging from 24h,48h,72h after radiation, compared to the blank control group. SAS was used for analysis.Results:1.Neural stem cells were cultured separately added with epidermal growth factor or the combination of epidermal growth factor and fibroblast growth factor .It appears that propagating neurospheres in the presence of epidermal growth factor alone results in a greater degree of commitment to glial lineages, whereas fibroblast growth factor allows for a greater extent of neurons.2.In the proliferation studies, different doses of magnesium sulfate were added into neural stem cell culture medium, It appears that the dose of magnesium sulfate affect the proliferation of neural stem cells. If the concentration is greater than a certain limit would result in the death of neural stem cells, or it would promote the proliferation of neural stem cells within a confined area.3. Neural stem cells were irradiated with 2Gy or 4Gy gamma rays , compared with blank control group ,the proliferation rate of experimental control group significantly reduced(p<0.05), whereas, compared with experimental control group ,the proliferation rate of experimental group significantly increased excluding the time of 24h point(p<0.05).4. Neural stem cells were irradiated with 2Gy or 4Gyγrays , compared with blank control group ,the apoptosis rate of experimental control group significantly increased(p<0.05), whereas, compared with experimental control group ,the apoptosis rate of experimental group significantlyreduced(p<0.05).5. Neural stem cells were irradiated with 2Gy or 4Gyγrays , compared with blank control group ,the G1 phase arrest of experimental control group significantly increased(p<0.05) and the G2 phase arrest increased slightly, it appears that 4Gy was significant , whereas, compared with experimental control group ,the G1 phase arrest of experimental group significantly decreased(p<0.05),it is closer to the blank control group.Conclusions:1. Epidermal growth factor can promote neural stem cells to differentiate more glial cells. Fibroblast growth factor allows for a greater extent of neurons.2. Within the scope of a certain dose of magnesium sulfate can promote the proliferation of neural stem cells.3. Magnesium sulfate can inhibit the injury of proliferation in the early stage after irradiation.4. Magnesium sulfate can decrease the apoptosis caused by ionizing radiation.5. Magnesium sulfate can decrease the G1 phase arrest caused by ionizing radiation.