川芎嗪预处理骨髓间充质干细胞移植对脑缺血大鼠神经细胞凋亡的影响

Effects of tetramethylpyrazine preconditioning BMSCs transplantation on neuronal apoptosis in rats with cerebral ischemia

目的:探讨川芎嗪(TMP)预处理骨髓间充质干细胞(BMSCs)移植对脑缺血大鼠神经细胞凋亡及Bcl-2、Bax表达的影响。方法:采用全骨髓贴壁法分离BMSCs,川芎嗪(50、100μmol/L)预处理24h。线栓法诱导大鼠大脑中动脉阻塞模型,分假手术组、模型组、BMSCs组和川芎嗪预处理组。缺血后第1、7和14天,采用改良的神经损伤严重程度评分(m NSS)和角试验进行神经功能评价;缺血后第14天,采用原位末端标记(TUNEL)法观察神经细胞凋亡,Western blot法检测Bcl-2和Bax蛋白的表达。结果:与BMSCs组比较,川芎嗪预处理组大鼠m NSS评分和右转次数均显著减少,TUNEL阳性细胞数显著减少(P<0.05,P<0.01),Bcl-2蛋白表达显著上调,Bax蛋白表达显著下调(P<0.05,P<0.01)。结论:川芎嗪预处理BMSCs移植促进脑缺血大鼠神经功能恢复,机制可能与其调控Bcl-2/Bax表达抑制神经细胞凋亡有关。

Objective: To observe the effects of tetramethylpyrazine(TMP) preconditioning bone marrow mesenchymal stem cells(BMSCs) transplantation on neuronal apoptosis and the expression of Bcl-2/Bax in rats with cerebral ischemia. Methods: BMSCs were cultured by the whole bone marrow adherent method in vitro, BMSCs were preconditioned with TMP(50, 100μmol/L) for 24 h. Middle cerebral artery occlusion(MCAO) model was established by using suture method. SD rats were randomly divided into sham group, MCAO group, BMSCs group and BMSCs preconditioned with TMP groups. The neurological function was evaluated by modified neurological severity scores(m NSS) and corner test after ischemia. The neuronal apoptosis was detected by terminal deoxynucleotidyl transferase-mediated d-UTP nick end labeling(TUNEL). The protein expressions of Bcl-2 and Bax were analyzed by Western blot 14 days after ischemia. Results: Compared with BMSCs group, the score of m NSS and the number of right turn were significantly reduced, TUNEL positive cells were significantly decreased(P<0.05. P<0.01), Bcl-2 protein expression was increased, whereas the expression of Bax was decreased(P<0.05, P<0.01). Conclusion: TMP preconditioning BMSCs can significantly promote functional recovery in rats with cerebral ischemia, the mechanism may be related to inhibit neuronal apoptosis by regulating Bcl-2/Bax expression.