人胰岛素样生长因子-1基因修饰的神经干细胞移植对缺氧缺血性脑损伤新生大鼠的治疗作用

摘要

Objective To explore the curative effect of insulin - like growth factor - 1 ( IGF - 1 ) gene modified neural stem cells ( NSCs - IGF - 1 ) transplantation on newborn rat models with hypoxic - ischemic brain damage(HIBD).Methods HIBD rat models were established in the way of ligation of the left common carotid artery and subjected to hypoxia.The rats were randomly divided into 4 groups:normal control group, HIBD control group, NSCs transplantation group and NSCs - IGF - 1 transplantation group.Cell transplantation was carried by tail vein injection.One day, 7 days,14 days and 21 days after transplantation, 5 rats in per group were killed respectively.Immunocytochemical staining for BrdU, Nestin were applied to observe the survival and distribution of the transplanted cells in vivo; Y - maze test and motor behavioral tests were performed as well to research the recovery of brain function of rats in different groups.Results Seven days after transplantation, BrdU -pesitive cells could be observed in both NSCs- IGF- 1 transplantation group and NSC transplantation group, and the former was significantly better than the latter ( P ＜ 0.05 ).Within the observation time, the expression of Nestin positive cells in NSCs - IGF - 1 transplantation group increased soon after transplantation, and it reached a peak on the 14th day,and then declined gradually.But Nestin positire and NSE positive cells in model control group decreased gradually from 7 days after transplantation.There was significant difference betwcen the 2 groups ( P ＜ 0.0l ).Fourteen days after transplantation, Nestin positive and NSE positive cells in NSCs - IGF - 1 transplantation group were significanfiy higher than those in NSCs transplantation group (Pa ＜ 0.01 ).Examinations on the rats learning, memorizing abilities and motor behavioral tests showed that those in NSCs - IGF - 1 transplantation group were significantly better than those in the control group and NSCs transplantation group ( Pa ＜ 0.01,0.05 ).Conclusions NSCs and NSCs - IGF - 1 can survive, proliferate and differentiate in brain of HIBD rats, and the nervous function recovery can be promoted partly by transplanting them.The effect of the NSCs - IGF - 1 is better than single NSCs.%目的 探讨胰岛素样生长因子-1(IGF-1)基因修饰神经干细胞(NSCs-IGF-1)移植对缺氧缺血性脑损伤(HIBD)新生大鼠脑功能恢复的治疗作用.方法 采用结扎大鼠左侧颈总动脉,低氧箱中缺氧处理的方法,制成新生大鼠HIBD模型,随机分为正常对照组、模型对照组、神经干细胞(NSCs)移植组和NSCs-IGF-1移植组,尾静脉注入法进行干细胞移植.分别于移植1 d、7 d、14 d、21 d 取5只大鼠脑组织进行病理切片,通过5-溴脱氧尿嘧啶(BrdU)、巢蛋白(Nestin)、神经元特异性烯醇化酶(NSE)免疫组织化学染色观察NSCs在宿主脑内存活及增殖和分化情况,并通过Y-迷宫实验和运动功能检测对剩余大鼠脑功能恢复情况进行观察.结果 移植7 d后,NSCs移植组和NSCs-IGF-1移植组均可见到BrdU阳性细胞,二组比较差异有统计学意义(P<0.05).在观测时间点内,NSCs-IGF-1移植组Nestin阳性细胞表达量早期升高,移植后14 d达峰值,后逐渐下降;NSE阳性细胞表达量逐渐升高.模型对照组在移植7 d后Nestin及NSE阳性细胞表达量逐渐降低,2组比较差异均有统计学意义(Pa<0.01).移植14 d,NSCs-IGF-1移植组Nestin及NSE阳性细胞表达量均明显高于NSCs移植组(Pa<0.01).大鼠学习记忆功能检测及运动功能检测结果均显示NSCs-IGF-1移植组明显优于模型对照组及NSCs移植组,二者差异均具有统计学意义(Pa<0.01,0.05).结论 NSCs及NSCs-IGF-1可以在脑内存活、增殖及分化,并可部分促进缺氧缺血大鼠脑功能的恢复;NSCs-IGF-1较单独移植NSCs效果好.