Catwalk系统评估脐带间充质干细胞移植治疗大鼠脑损伤后运动功能的恢复情况

摘要

目的 应用Catwalk步态分析系统评价脐带间充质干细胞(UC-MSCs)治疗脑损伤后的功能恢复情况.方法 采用重物坠落模型制作脑损伤模型.成年Wistar大鼠分成3组:移植治疗组,脑损伤后第7天移植DiO标记的UC-MSCs;损伤对照组,损伤后第7天注射等量生理盐水；正常对照组不接收任何手术和治疗.按照分组,分别在大鼠损伤前、损伤后3d以及UC-MSCs移植治疗后7d,以改良神经损伤程度评分(mNSS)为经典评估参照指标,同步对实验鼠进行Catwalk步态分析检测,并于移植后14d进行脑片免疫组化染色观察,评价以Catwalk步态分析系统检测UC-MSCs治疗脑损伤后功能恢复情况的灵敏度.结果 细胞移植后7d,损伤组和移植组的mNSS评分有统计学差异(P＜0.05)；而Catwalk则从大鼠每一只爪子的压力、长度、宽度、面积、步幅等不同量化的角度,呈示了损伤组各参数与正常组之间的差异(P＜0.05),以及移植组和损伤组之间的部分差异；移植治疗组的损伤灶区显示,DiO标记的UC-MSCs呈GFAP和β-Tubulin Ⅲ阳性表达.结论 以Catwalk步态分析系统评估损伤大鼠治疗前后的运动功能情况更为敏感客观,可准确评价UC-MSCs移植治疗TBI并促进脑功能恢复的情况.%Objective To assess the effect of CatWalk automated gait analysis system for evaluation of motor function of rats with traumatic brain injury (TB1) after umbilical cord mesenchymal stromal cell (UC-MSC) treatment.Methods Eighteen Wistar rats were randomized equally into normal control group,TBI + saline group,and TBI + UC-MSCs group.The rats in the latter two groups were subjected to weight-drop impact to induce TBI followed by injection UC-MSCs or saline into the lesion 7 days after TBI.The neurological function was assessed using CatWalk system and modified neurological severity scores (mNSS) before and 3 days after TBI and 7 days after UC-MSC transplantation.The rats were sacrificed 14 days after the cell transplantation and the brain sections were stained for immunohistochemical analyses.Results Three days after TBI,mNSS test showed moderate injury of the rats.Seven days after the cell transplantation,the rats showed significant motor function improvement and CatWalk analysis indicated partial recovery of the gait parameters of the 4 limbs compared to the rats with saline treatment.Histological analyses showed that DiO-labeled UC-MSCs were present in the lesion boundary and expressed glial fibrillary acidic protein and fi-tubulin III.Conclusion UC-MSC transplantation can promote functional improvement of the brain after TBI in rats.Compared with mNSS test,CatWalk analysis is more sensitive and objective for assessing neurological function and also provides more detailed information on specific gait parameters.