摘要
目的通过观察miRNA-9在骨髓间充质干细胞（MSCs）分化为神经元过程中的作用，探讨基因修饰在脊髓损伤治疗中的作用。方法分离培养大鼠MSCs并构建miRNA-9-1慢病毒载体。成功建立84只大鼠急性脊髓损伤模型，并按照随机数字表法分为对照组、MSCs组及miRNA组，每组28只。脊髓损伤后l周，对MSCs组大鼠进行MSCs移植，对miRNA组大鼠移植miRNA-9-1慢病毒载体感染的MSCs，对照组大鼠仅在损伤部位注射等量的生理盐水。选择不同时间点对大鼠后肢进行Basso Beattie Bresnahan（BBB）评分，并行神经丝蛋白200（NF-200）和胶质纤维酸性蛋白（GFAP）免疫组织化学染色，对各组阳性表达面积百分比进行比较。结果细胞移植4周后，各组大鼠BBB评分差异有统计学意义，其中miRNA组评分较MSCs组及对照组明显提高。差异有统计学意义（P〈0．05）。免疫组织化学染色示miRNA组的NF-200阳性面积较MSCs组及对照组明显增大，GFAP阳性面积较MSCs组及对照组明显减小，各组间的差异具有统计学意义（P〈0．05）。结论miRNA-9在MSCs横向分化为神经元中起重要调控作用，并通过促进轴突再生．减，少脊髓损伤部位反应性胶质细胞的数量等机制促进脊髓损伤后的功能修复。
Objeetive To assess the role of microRNA-9 in bone marrow mesenchymal stemcells differentiating into neurons and research the role of gene modification in spinal cord injury treatment. Methods Adherent culture was used to isolate and culture rat bone marrow mesenchymal stem cells （MSCs）; microRNA-9-1 lentiviral vector was constructed. Acute spinal cord injury （SCI） models were established in 84 adult SD rats at T10/11 level according to the improved Allen＇s method; then, they were randomly divided into control group, MSCs group and miRNA group （n=28）. One week after SCI, the rats of MSCs group were treated with MSCs implantation, and the rats ofmiRNA group were treated with MSCs-transfected microRNA-9-1 lentiviral vector; while rats of the control group only received the same amount of physical saline in the same region. The neurological fimctions were evaluated by using Basso-Beattie-Bresnahan （BBB） scale 1 and 3 days, and 1, 2, 4, 6, 8 and 12 weeks after SCI. The immunoreactivity of neuro filament 200 （NF-200） and glial fibrillary acidic protein （GFAP） was measured, and the percentage of positive response area was assayed and compared between groups. Results Four weeks after cell transplantation, statistical difference of BBB scale scores was noted between each two groups; the scores of miRNA group were significantly higher than those of the MSCs group and control group （P〈0.05）. The immunohistochemistry staining indicated that the expression of NF-200 was significantly more intense and the expression of GFAP was significantly weaker in miRNA group than those of the other two groups （P〈0.05）. Conclusion MicroRNA-9 may play an important role in bone marrow mesenchymal stem cells differentiating into neurons, and possesseffects on repairing injured spinal cord and promoting functional recovery through promoting axonal regeneration and reducing the number of reactive glial cells in the spinal cord injury site.
出处
《中华神经医学杂志》
CAS
CSCD
北大核心
2012年第12期1204-1208,共5页
Chinese Journal of Neuromedicine
关键词
间充质干细胞
脊髓损伤
慢病毒载体
Marrow mesenchymal stem cell
Spinal cord injury
Lentiviral vector
