Effect of neural stem cells transplantation on neurocyte apoptosis and bcl-2 expression of rat after spinal cord injury

Objective To study effects of neural stem cells(NSCs)transplantation on neurocyte apoptosis and bcl-2 expression of rat after spinal cord injury(SCI).Methods 40 SD rats were divided into four groups randomly:Normal group,SCI group,NSCs group and BrdU+NSCs group.SCI model was induced with electrocircuit control spinal cord injuring device.NSCs in logarithmic phage were labeled with Brdu.The NSCs were transplanted into the injured site after SCI.The expression of Brdu and bcl-2 were detected by immunohistochemisty,and cell apoptosis of TUNEL were used to observe neural cell(immunohistochemisty and immunofluorescence).The improved Rivlin method(namely,slope test)was used to assess the motor function following spinal cord injury in rats.Results NSCs labeled with Brdu could be detected in the spinal cord after transplantation.TUNEL positive cells were significantly decreased at each time point in NSCs group and BrdU+NSCs group than that of SCI group(P0.01),the grey level of bcl-2 positive neurons at each time point in NSCs group and BrdU+NSCs group were higher than those of SCI group(P0.01),the expression peak of bcl-2 was postponed and reached the peak on 7thd.On 7thd,14thd and 28thd after transplantation,inclined plane test of NSCs group and BrdU+NSCs group were higher than those of SCI group(P0.01).There were no significant differences between NSCs group and BrdU+NSCs group(P0.05).Conclusion The transplantation of NSCs can survive in the injured site of spinal cord,upregulate more obviously the expression of bcl-2 and inhibit neurocyte apoptosis after spinal cord injury,then promote more remarkably functional recovery of hind limb in rat after SCI.