神经干细胞移植对大鼠脊髓损伤后GDNF基因表达的影响及意义

Effect of neural stem cell transplantation on glial cell line-derived neurotrophic factor after spinal cord injury in rats

目的:探讨神经干细胞(NSC)移植对大鼠脊髓损伤后胶质细胞源性神经营养因子(GDNF)表达的影响及其意义。方法:NSC提取自新生Wistar大鼠的海马区,经培养、鉴定。制作大鼠脊髓损伤(SCI)模型,于伤后第7d移植NSC。实验分为3组:NSC移植组(A组)、DMEM填充组(B组)、正常对照组(C组)。应用RT-PCR法和免疫组化法观察细胞移植后不同时间点GDNF基因的表达变化。结果:RT-PCR结果分析,移植术后第1,3,5d,A组GDNF mRNA的表达量明显高于B组,差别有显著性意义(P<0.05)。组化结果分析,移植术后第7,14,28d GDNF的表达量明显高于B组,差别有显著性意义(P<0.05)。结论:NSC在移植后可上调神经营养因子GDNF基因的表达,是修复脊髓损伤的机制之一。

Objective： To observe the effect of neural stem cell （NSC） transplantation on glial cell line-derived neurotrophic factor （GDNF） after spinal cord injury （SCI） in rats, and to investigate the mechanism of repairing SCI by NSC transplantation. Methods： NSCs derived from the hippocampus of neonatal rats were cultured and identified by immunocytochemistry. Sixty adult Wistar rats were randomly divided into 3 groups. The rat model of SCI was established in groups A and B, and the rats were injected with NSCs in group A and DMEM solution in group B 7 days after SCI, respectively. The rats in group C were normal controls. The expression of GDNF at the injured site and in the adjacent areas was detected by reverse transcription polymerase chain reaction （RT-PCR） and immunohistochemistry. Results ： The results of RT-PCR showed that the expression of GDNF mRNA in group A was significantly higher than that in group B on days 1, 3, and 5 of NSC transplantation. The results of immunohistochemistry indicated that the expression of GDNF in group A was significantly higher than that in group B on days 7, 14, and 28 of NSC transplantation. Conclusion ： The transplantation of NSC could up-regulate the expression of GDNF, which may be one of the mechanisms of repairing SCI by NSC transplantation.