摘要
目的探讨移植胶质细胞源性神经营养因子(GDNF)基因修饰的骨髓基质干细胞(BMSCs)对大鼠脑出血后神经细胞凋亡及凋亡相关基因表达的影响。方法通过脑立体定位仪向SD大鼠脑尾壳核注射胶原酶和肝素建立脑出血动物模型,将48只模型大鼠随机分为BMSCs组、GDNF/BMSCs组和生理盐水组,各组又根据细胞移植后再喂养时间的不同(1周、2周)分为2个亚组,每亚组8只大鼠。于建模后第3天在脑出血部位分别移植BMSCs、GDNF/BMSCs或注射生理盐水,采用神经功能缺失评分和HE染色评估大鼠神经功能缺失情况和脑损伤面积,RT-PCR法观察GDNF mRNA的表达,原位缺口末端标记法(TUNEL)和免疫组织化学染色观察细胞凋亡数及Bax和Bcl-xl蛋白的表达。结果与生理盐水组和BMSCs组相比,GDNF/BMSCs组神经功能恢复更好,脑损伤面积所占比率显著降低,GDNF mRNA表达上调,凋亡细胞数明显下降。在1周和2周时间点,GDNF/BMSCs组与BMSCs组和生理盐水组相比,Bcl-xl阳性细胞数明显增加,而Bax阳性细胞数则减少。结论 GDNF基因修饰的BMSCs移植至脑出血大鼠后,可能通过上调GDNF基因的表达、抑制细胞凋亡、增加Bcl-xl蛋白的表达和降低Bax蛋白的表达发挥神经保护作用。
Objective To explore the effects of bone marrow stromal cells （BMSCs） transplantation modified by glial cell line-derived neurotrophic factor （GDNF） gene on neuronal apoptosis and the expression of apoptosis-related genes in rats with intracerebral hemorrhage. Methods Forty-eight rats were used to establish the model of intracerebral hemorrhage by injecting with collagenase and heparin into caudate nucleus through stereotaxic apparatus. The rats were randomly divided into BMSCs group, GDNF/BMSCs group and saline group, and were stereotaxically grafed with BMSCs, GDNF/BMSCs and saline respectively at the 3rd day after operation. Each group was subdivided into two subgroups according to different refeeding time （ 1 week, 2 weeks）. Neurological function and area of brain injury were assessed by neurological deficits score and HE staining respectively. Expression of GDNF mRNA was observed by RT-PCR. The number of neuronal apoptosis and the expressions of Bax and Bcl-xl in the margin of the hemorrhagic focus were observed by TUNEL and immunohistochemistry. Results Significant recovery of neurological function and increase of GDNF mRNA expression were found in the GDNF/BMSCs group compared with BMSCs and saline group. Both rate of brain injury area and the number of neuronal apoptosis in the GDNF/BMSCs group were significantly less than other groups. As compared with the BMSCs and saline group, the number of Bcl-xl positive cells increased in the GDNF/BMSCs group, while the number of Bax positive cells decreased. Conclusion The transplantation BMSCs modified by GDNF gene provides better neuroproteetion than native BMSCs. The underlying mechanisms may be due to partly inhibited apoptosis, and the expression of up-regulated Bcl-xl and down-regulated Bax protein.
出处
《解剖学报》
CAS
CSCD
北大核心
2011年第6期731-736,共6页
Acta Anatomica Sinica
基金
四川省卫生厅科研基金资助项目(100224)
四川省教育厅科研基金资助项目(2006A155)
