脑缺血恢复期骨髓间充质干细胞移植对神经功能和促血管生成素-1、2及其受体表达的影响

Effects of bone marrow mesenchymal stem cells transplantation at cerebral ischemia recovery stage on neurological function and expressions of angiopoietins-1,2 and their receptor

目的探讨脑缺血恢复期骨髓间充质干细胞(BMSCs)移植对神经功能和促血管生成素(Ang)-1、Ang-2及酪氨酸激酶受体-2(Tie-2)表达的影响。方法 42只SD大鼠随机分为脑缺血对照组(对照组,12只)、BMSC移植组(15只)及假手术组(15只),各组又分为缺血后28d、35d、42d3个亚组。用线栓法制作脑缺血大鼠模型,用改良黏附物移除试验(MST)评估大鼠神经功能。在脑缺血后21d,给BMSCs移植组大鼠尾静脉注射BMSCs,对照组大鼠注射等体积PBS。在脑缺血后28d、35d、42d(移植后7d、14d、21d),用逆转录-聚合酶链反应(RT-PCR)及WesternBlotting法检测大鼠缺血周围脑组织Ang-1、Ang-2及Tie-2mRNA和蛋白的水平。结果 BMSCs移植组大鼠各时间点亚组的MST评分均显著高于对照组(均P<0.05);BM-SCs移植组及对照组各时间点亚组脑组织的Ang-1、Tie-2mRNA和蛋白水平明显高于假手术组(P<0.05～0.01),脑缺血后28d、35d,BMSCs移植组脑组织Ang-1、Tie-2mRNA及蛋白水平均明显高于对照组(均P<0.01),而脑缺血后42d两组之间的差异无统计学意义;3组各时间点亚组脑组织Ang-2mRNA及蛋白水平的差异均无统计学意义。结论脑缺血恢复期BMSCs移植能改善神经功能,并使缺血周围脑组织Ang-1、Tie-2的表达水平明显增高,而对Ang-2表达无明显影响。

Objective To explore the effects of bone marrow mesenchymal stem cells （BMSCs） transplantation at cerebral ischemia recovery stage on the neurological function and expressions of angiopoietins（Ang）-1,Ang-2 and Tie-2.Methods 42 SD rats were randomly divided to cerebral ischemia control group （control group,n=12）,BMSCs transplanted group（n=15） and sham operation group（n=15）,and each group was divided to 28 d,35 d,42 d after cerebral ischemia sub-groups.Models of cerebral ischemia rats were made with thread embolism method.Modified adhesive removal test （MST） was taken for the assessment of neurological function in the rats.After cerebral ischemia 21 d,the BMSCs were administrated through tail vein in the BMSCs transplanted group,while the same volume of PBS was administrated in the control group.At 28 d,35 d,42 d after cerebral ischemia （7 d,14 d and 21 d after BMSCs transplantation）,the mRNA and protein levels of Ang-1,Ang-2 and Tie-2 of the rats cerebral ischemic boundary tissues were detected with RT-PCR and Western Blotting.Results The scors of MST in the BMSCs transplanted group were significantly higher than that in the control group at each time point subgroups （all P〈0.05）.The mRNA and protein levels of Ang-1,Tie-2 at cerebral tissues in BMSCs transplanted group and the control group were significantly higher than those in the sham-operated group at each time point subgroups （P〈0.05-0.01）.In the 28 d,35 d after cerebral ischemia subgroups,the mRNA and protein levels of Ang-1,Tie-2 at cerebral tissues in the BMSCs transplanted group were significantly higher than those in the control group （all P〈0.01）,however there was no significant difference between two the 42 d after cerebral ischemia subgroups.In three groups each time point subgroup,the mRNA and protein levels of Ang-2 at the cerebral tissues had no significant difference.Conclusions BMSCs transplantation at the recovery stage of cerebral ischemia can improve the neurological function,as well as increase the expression of Ang-1,Tie-2 at the cerebral ischemic boundary tissues.However it has no significant effect on the expression of Ang-2.