动脉移植BMSCs对脊髓缺血再灌注损伤大鼠脊髓细胞凋亡和caspase-9基因的影响

Effects of the bone marrow mesenchymal stem cells transplanted by abdominal aortic on apoptosis and caspase-9 in spinal cord of rats with spinal cord ischemic reperfusion injury

目的探讨肾下腹主动脉移植骨髓间充质干细胞(BMSCs)对缺血再灌注损伤脊髓细胞凋亡、caspase-9表达及功能恢复的影响。方法将大鼠随机分为假手术组、缺血再灌注组、移植组,每组8只。假手术组仅行手术操作;缺血再灌注组阻断肾下腹主动脉120 min后开放,恢复脊髓再灌注5 min后经动脉留置管推注1 m L培养基;移植组恢复再灌注5 min后推注100万BMSCs悬液1 m L。术后1、3和7 d对大鼠进行BBB评分;用RT-PCR、Western blot检测术后7 d大鼠缺血节段脊髓内caspase-9基因和蛋白表达,TUNEL观察细胞凋亡。结果缺血再灌注组和移植组大鼠BBB评分于术后1、3和7 d均显著低于假手术组(P<0.01),移植组术后3、7 d BBB评分高于缺血再灌注组(P<0.01);移植组和缺血再灌注组损伤脊髓caspase-9 mRNA和蛋白表达水平较假手术组增加(P<0.01),缺血再灌注组增加更为显著(P<0.01)。缺血再灌注组和移植组损伤脊髓内出现大量凋亡细胞,而移植组凋亡细胞数少于缺血再灌注组(P<0.01)。结论肾下腹主动脉移植BMSCs可通过抑制缺血再灌注损伤脊髓caspase-9表达,减轻脊髓局部细胞凋亡,改善其神经功能恢复。

Objective To investigate the functional recovery and effects of the bone marrow mesenchymal stem cells （BMSCs） transplanted by abdominal aortic on apoptosis and caspase-9 in spinal cord ischemic reperfusion injured （SCIRI） rats.Methods Twenty-four adult female SD rats were assigned randomly into 3 groups （8 rats in each group）.Rats in the sham group were subjected to the operative procedure but short of blocking abdominal aorta.Rats in the control group and the transplantation group were subjected to abdomen aorta occlusion for 120 min to induce spinal cord ischemia,and then the aorta was reopened for spinal cord reperfusion.Five minutes later,10％ FBS culture medium and BMSCs suspension were injected by the arterial trocar respectively.BBB scores was assessed at 1,3 and 7days after the operation.RT-PCR and Western blot were used to detect the expressional changes of caspase-9 and TUNEL was used to observe apoptosis in the lumbar segments of spinal cord.Results Compared with the sham group,BBB scores in the transplantation group and the control group decreased obviously at 1,3 and 7days post operation （P ＜0.01）.However,the scores in the transplanted rats were much higher than that in the control group （P ＜0.01）.The mRNA and protein level of caspase-9 was increased greatly in the SCIRI rats,but the level in the transplantation group was lower than that in the control group （P ＜0.01）.Apoptosis had been detected in the injuried cords,the number of apoptosis in the transplantation group was fewer than that in the control group （P ＜ 0.01）.Conclusions BMSCs,transplanted by the abdominal aorta,can promote the functional recovery by inhibiting the expression of caspase-9 and reducing the occurrence of apoptosis in the injuried spinal cord.