摘要
Abstract
Objective: To explore the differentiation of the marrow stem cells (MSCs) in vitro, the mechanism of neural repair and behavioral change mediated by MSCs transplantation, and observe the role of growth associated protein-43 in neuronal plasticity following cerebral ischemia/reperfusion injury. Methods: 118 adult male Wister rats were divided randomly into sham-operation group (n=42), cerebral ischemia/reperfusion group (n=42) and cell transplantation group (n=30). According to the time points of reperfusion, each group was divided into 7 subgroups: 3 h, 8 h,16 h, 48 h and 5 d, 9 d, 16 d (n=6 each). All ischemia duration was 1 h. MSCs transplantation was performed after the reperfusion at each time point (n=6). Another 4 Wistar rats severed as donors of MSCs transplantation. Following reperfusion in each time point brain tissue was obtained. The MSCs were induced by basic fibroblast growth factor (bFGF) and epidermal growth factor (EGF) in vitro and identified as nerve-like stem cells, neuron-like cells, neurogliocyte-like cells by Nestin, 5-bromodeoxyuridine (BrdU) and glial fibrillary acidic protein (GFAP) respectively.Neurological behavior detection and neurological scoring were performed respectively after MSCs transplantation.Modified suture method was used to establish the models of middle cerebral artery occlusion/reperfusion (MCAO/R),and TUNEL method was applied to observe the distribution of apoptosis in cortex region and hippocampal region, and GAP-43 positive neurons were detected by immunohistochemistry in two regions. The formation of infarction in cerebral ischemic penumbra and the dynamic change of directed migration of transplanted cells were observed. Results: In the reperfusion 9 d group, the number of GAP-43 positive neurons reached the peak and was significantly increased as compared with sham operation group (P＜0. 01). In the reperfusion 16 d group, apoptosis rate reached the maximum (P＜0. 01). In the cell transplantation 5 d group, infarction area was significantly increased as compared with ischemia/reperfusion group (P＜0. 01). In the cell transplantation 9 d group, the number of transplanted neurons reached the peak (P＜0. 01). In the cell transplantation 16 d group, neural function score was obviously decreased (P＜0. 01). Conclusion: The repair of infarction area in cerebral ischemic penumbra is mediated by the transplantation of MSCs. The expression of GAP-43 inhibits apoptosis of neurons and promotes the plasticity of cerebral nerves.关键词
脑缺血/再灌注损伤/骨髓间充质干细胞/GAP-43/移植/再生Key words
cerebral ischemia/reperfusion injury/ the marrow stem cells/ the growth-associated protein-43/ transplantation / regeneration分类
医药卫生
