臂丛损伤神经干细胞脊髓前角移植后分化情况及对运动神经元的保护作用

目的观察臂丛根性撕脱伤后将脊髓源性神经干细胞(neuralstemcell,NSC)移植于脊髓前角后的存活、分化情况及对脊髓前角受损运动神经元的保护作用。方法取新生鼠脊髓,分离获得脊髓源性神经干细胞,体外培养、扩增、鉴定、5溴2-脱氧尿苷(BrdU)标记。取SD大鼠60只,随机分成实验组、对照组和单纯组。从后路制备C5~C7臂丛神经根性撕脱伤动物模型。实验组移植神经干细胞于C6脊髓前角,对照组移植灭活神经干细胞,单纯组不作移植。术后1、2、4、8、12周取脊髓标本进行组织学与免疫组化染色观察。结果神经干细胞移植入脊髓后能存活、分化;臂丛根性撕脱伤后脊髓前角运动神经元数目明显减少;实验组神经干细胞移植后2、4、8、12周各个时间点运动神经元的存活率均高于对照组和单纯组。结论臂丛根性撕脱伤脊髓前角神经干细胞移植后能存活并分化为神经元及星型胶质细胞,脊髓源性神经干细胞移植能明显减少前角运动神经元的继发性死亡,对脊髓前角受损运动神经元有保护作用。

An experimental study on differentiation of transplanted neural stem cells and the protective effect on motoneurons after brachial plexus avulsion injuries

Objective To study the survival, migration, differentiation of neural stem cells transplanted into ventral horn of the spinal cord following brachial plexus avulsion, and their protective effect on motoneurons. WTHZ Methods Neural stem cells isolated from spinal cord of neonatal rats were cultured, expanded, labeled by BrdU before being transplanted. C_ 5-7 root avulsion of the brachial plexus was created via posterior approach in 60 adult SD rats. The animals were then randomly divided into three groups. In vitro cultured neural stem cells were transplanted into the ventral horn spinal cord of C_6 level in the experimental group. Dead stem cells were transplanted in the sham experimental group. No cell transplantation was done in the control group. In 1, 2, 4, 8, and 12 weeks postoperatively, histologic and immunohistochemistry assays of the spinal cord were carried out. Results After being transplanted into ventral horn of the spinal cord, neural stem cells can survive, migrate for one segment of the spinal cord and differentiate into neurons and astrocytes. The number of motoneurons in the ventral horn of the spinal cord decreased markedly after brachial plexus avulsion. The survival rate of motoneurons in the experimental group was higher than that in the sham transplantation group and control group at 2, 4, 8, and 12 weeks postoperatively. WTHZ Conclusion Neural stem cells can survive, migrate and differentiate after being transplanted into ventral horn of the spinal cord. They exert motoneuron protective effect that decreases the secondary death of motoneurons of the ventral horn in brachial plexus avulsion injuries.