目的初步探讨骨髓间充质干细胞 (bone marrow mesenchymal stem cells,BM-MSCs)治疗新生重度缺氧缺血性脑损伤大鼠神经营养因子的表达及其与疗效的关系。方法60只6日龄SD大鼠被随机分为手术对照组(NS组)、空白对照组(BC组)和干细胞移植组(MSC组),每组20只,制备重度缺氧缺血性脑损伤大鼠模型。将BM-MSCs经体外培养、扩增后,经枕大池移植到MSC组模型大鼠的蛛网膜下腔中,NS组用相同体积的生理盐水代替BM-MSCs,BC组于模型建立后不进行任何移植。经上述处理后3、7、14、21 d对大鼠进行改良神经功能缺损评分(modified neurological severity scores,mNSS),同时收集大鼠脑脊液检测神经生长因子(nerve growth factor,NGF)、脑源性神经营养因子(brain-derived neurotrophic factor, BDNF)、神经营养素-3(neurotrophin-3,NT-3)、胶质细胞源性神营养因子(glia cell line-derived neurotrophic factor,GDNF)等神经营养因子的表达。结果MSC组及NS组大鼠在移植后第7、14和21天,其mNSS评分与移植前和移植后第3天相比较差异均有统计学意义(P＜0.05)。MSC组、NS组及BC组移植后21 d mNSS评分分别为7.0±2.8、10.0±3.7和11.0±1.6。与第3天比较,BC组仅在移植后21 d出现差异并具有统计学意义(P＜0.05),移植后7 d和14 d差异无统计学意义。脑脊液检测发现MSC组神经营养因子NGF、NT-3、BDNF及GDNF的表达较移植前有显著增加(P＜0.05),而NS组和BC组表达反而减少(P＜0.05)。结论经枕大池移植BM-MSCs对脑损伤大鼠神经功能恢复具有促进作用,推断NGF、NT-3、BDNF、GDNF等神经营养因子在其中起重要作用,其具体作用机制有待进一步研究。

Objective To study the expression changes in nerve growth factor (NGF) and brain derived neurotrophic factor (BDNF) and nerve nutriment-3 neurotrophin-3 (NT-3), glia cell line - derived neurotrophic factor (GDNF) in the process of bone marrow mesenchymal stem cells (BM-MSCs) therapy to newborn rats with severe hypoxic ischemic brain damage and relationship with improvement of neural function. Methods The rat models of severe hypoxic ischemic brain damage developed by the right common carotid artery ligation +oxygen deficit(number=60)were divided into stem cell treatment group(MSC group, number=20), the operation control group(NS group, number=20)and blank control group(BC group, number=20) randomly.We transplanted BM-MSCs cultured and amplified in vitro into cerebrospinal fluid of model rats through cisterna magna. Movement of rats was assessed with modified Neurological Severity Scores (mNSS) at day 3, day 7, day 14 and day 21 after transplantation.NS group used the same volume of normal saline instead of BM-MSCs and mNSS evaluation time and method was the same as in MSC group. We established BC group the model with no transplantation and mNSS evaluation time and method was the same with MSC group,examined the expressions of NGF, BDNF, NT - 3and GDNF collected from rats, cerebrospinal fluid at day 3, day 7, day 14 and day 21 after transplantation. Results There was significant difference in mNSS scores between MSC group and NS group at day 7, day 14 and day 21 after transplantation(P＜0.05);Scores in MSC group, NS group and BC group were 7±2.8、10±3.7 and 11±1.6, respectively.And BC group had a variation only in day 21 after transplantation(P＜0.05). And there was apparent increase in the expression of neurotrophic factors in MSC group at day 3, day 7, day 14 and day 21 after transplantation by cerebrospinal fluid detection(P＜0.05). Conclusions BM - MSCs can promote recovery of neurological function in brain injury rats. NGF、NT-3、BDNF and GDNF play an important role in the process of the recovery of neural function,but the specific mechanism needs further research.