经脑室神经干细胞移植治疗脑室周围白质软化新生大鼠电镜下脑病理评估

Cerebral Pathological Evaluation under Electron Microscopy of Meonatal Rats with Periventricular Leukomalacia Treated with Neural Stem Cells Transplantation Intraventriculariy

目的对经脑室植入神经干细胞(NSCs)的脑室周围白质软化(PVL)新生大鼠进行电镜下脑病理和髓鞘形成评估,探讨NSCs移植对治疗早产儿PVL的可行性,以及胶质细胞源性神经营养因子(GDNF)对NSCs治疗PVL的影响。方法采用颈部正中切开双侧颈总动脉结扎法制备PVL模型。采用孕14 d SD大鼠大脑皮质制备NSCs。2日龄新生大鼠随机分为PVL对照组(PVL组),PVL加NSCs移植组(PVL加NSCs组),PVL加NSCs移植及GDNF组(PVL加NSCs加GDNF组),假手术对照组(Sham组),Sham加NSCs移植组(Sham加NSCs组),以及Sham加NSCs移植及GDNF组(Sham加NSCs加GDNF组)。NSCs移植组将NSCs调整为5×107L-1,将2μL移植液以0.5μL/min注入侧脑室内。GDNF干预组以100μg/L GDNF加入NSCs移植液中注入侧脑室。对2日龄PVL新生大鼠在建模后72 h进行经脑室NSCs移植,分别于移植第21天行电镜下脑病理和髓鞘形成评估。结果移植第21天,电镜显示,PVL组可见部分神经元固缩变形,细胞器减少,罕见髓鞘形成。PVL加NSCs组皮质部位神经元形态基本正常,脑白质内髓鞘形成明显增加。PVL加NSCs加GDNF组皮质改善以及髓鞘形成增多情况较PVL加NSCs组则更为明显。假手术各组未见明显变化。结论经脑室NSCs移植对早产儿PVL具有很大的治疗潜力,GDNF可能具有增强NSCs的治疗作用。

Objective To evaluate the brain pathological changes and myelinogenesis after exdogenous neural stem cells （NSCs） trans- plantation intraventrilarily in neonatal rats with periventricular leukomalacia （PYL） ,and to explore the feasibility of NSCs transplantation for the treatment of PVL in premature infants. Methods The PVL models were established by ligated carotid artery through meso neak opened. NSCs were prepared from embryonic rat brain with E14. Two - day - old neonatal rats were randomly divided into PVL group, PVL plus NSCs group, PVL plus NSCs plus glial cell line derived neurotrophic factor（GDNF） group, Sham group, Sham plus NSCs group, and Sham plus NSCs plus GDNF, 15 rats each group. The intraventricular transplantation of exdogenous NSCs was undertaken in two- day- old neonatal rats with either PVL or Sham group at 72 h after operation. The cerebral pathological change and myelinogenetie evaluation under electron microscopy was undertaken at 21 days after transplantation,respectively. Results It was observed under electron microscopy at 21 days after transplantation that there were either pyknosis, metamorphism and reduetive organelles in cortical neurons or sparse myelinogenesis in white matter in PVL group,and basically normal cortical neurons and increased myelinogenesis in PVL group with transplantation of NSCs, respectively. Furthermore, more significant improvement in cortical neurons and more myelinogenesis in white matter were found in PVL plus NSCs plus GDNF group. Conclusions Intraventricular transplantation of NSCs,which is a suitable route,is with a great potential feasibility for the treatment of PVL,the most common intractable brain injury in premature infants.