Proliferation And Differentiation Of Neural Stem Cells Transplantation In Rats With Cerebral Ischemia

Objective:To observe the effects of neural stem cells transplantation in rats’ striatum and subventricular zone on rat models of focal cerebral ischemia and reperfusion.Method:Hippocampus was extracted from fetal rat pregnant14days. Suspension culture was used to isolate rat NSCs, identified with Nestin. The left side of the brain that produce cerebral ischemia90min reperfusion model was made by middle cerebral artery occlusion method. Neurologic signs were assessed by By Zea Longa five quartering method,1,2,3level will determine the success of the model in rats. Neural stem cells were injected under the left striatum24hours after a successful stereotaxic instrument was built. The rats were randomly divided into normal group, sham operation group, model group, PBS group and ischemic graft ischemic neural stem cell transplantation group, which were observed in3days,7days,14days. Use a7-point evaluation criterion to assess the ischemia-induced neurological deficits; Forelimb damage to all the animals were evaluated with the foot-fault approach; Changes in infarct size was observed by TTC. Cell morphology and structure of the stroke side were investigated by Nigeria dyeing results; apoptosis and apoptosis-positive cell counts were studied by Tunel assay; Expression under the cortex and striatum and lateral ventricle area (SVZ) were observed by Brdu/NeuN, Brdu/GFAP, fluorescent double standard method. Positive cells were calculated by statistics.Results:1. The right hemiplegia was occurred in model group, saline group and neural stem cells group in varying degrees. TTC:compared to that of PBS ischemic transplant group, rats in ischemic transplantation of neural stem cell group have a smaller infarct volume..2. Nissl staining there was a large area of necrosis and apoptosis of neurons in ischemia group ischemic area. Damage mainly focused in the cortex and striatum. Degeneration of nerve cells damage range was significantly reduced in ischemic transplantation of neural stem cell group. 3. Tunel (apoptosis staining):the apoptosis of positive cells of ischemic transplantation of neural stem cell group were less than that of ischemic transplant PBS group at each time point.4. Double immunofluorescent labeling:In the SVZ region, endogenous neural stem cell proliferation began at the third day, and reached the peak at seventh day, at the14th day, it was significantly reduced. Among them, the number of Brdu/NeuN increased significantly in ischemic neural stem cell transplantation group compared with PBS ischemic transplant group (P<0.05). the number Brdu/GFAP significantly reduced in ischemic neural stem cell transplantation group compared to that of PBS ischemic transplant group, the difference was significant (P<0.05).5. A large number of cells in the cortex and striatum Brdu/GFAP was found positive in PBS ischemic transplant group, while it was significantly reduced in ischemic neural stem cell group.Conclusions:1. Both neurological deficits and coordination capacity of rats with cerebral ischemia have been significantly improved via transplantation of neural stem cells.2. Transplantation of neural stem cells can possibly promote the differentiation of endogenous NSCs into neurons, and reduce the differentiation towards glial cells.3. Transplantation of neural stem cells may change the ischemic microenvironment of striatum, which possibly inhibits the proliferation of glial cells.