摘要：

目的 探讨骨髓间充质干细胞（BMMSC）移植对脑出血大鼠模型神经功能的保护作用。方法 采用Ⅶ型胶原酶制备Sprague-Dawley大鼠右侧纹状体出血模型，改良神经功能缺损评分（mNSS）、免疫组织化学染色和TUNEL法观察BMMSC细胞移植治疗后1、 3、 7、14和28d大鼠神经功能改善程度、 脑源性神经营养因子（BDNF）表达变化和细胞凋亡情况。结果 不同处理组大鼠各观察时间点mNSS评分（均P=0.000）、凋亡细胞数目（均P=0.000）差异均有统计学意义。与对照组和模型组相比，移植组大鼠治疗后28dmNSS评分降低（P<0.05），且呈时间性递减，治疗后7、14和28dmNSS评分均低于治疗后1和3d（P<0.05）；治疗后1、 3、 7、14和28d，模型组和移植组大鼠凋亡细胞数目增加（P<0.05）且于治疗后7d达峰值（均P<0.05），治疗后14和28d凋亡细胞数目虽有所减少但仍高于治疗后1和3d（均P< 0.05）。移植组大鼠移植区及周围BDNF表达升高，偶见绿色荧光蛋白和胶质纤维酸性蛋白、绿色荧光蛋白和神经元核抗原双表达细胞，表明移植的BMMSC细胞已在宿主脑组织中存活并向神经元样细胞和神经胶质样细胞分化。结论 由胶原酶诱导的脑出血大鼠模型稳定，可用于脑出血研究。移植的BMMSC 细胞通过上调BDNF表达、减少细胞凋亡而发挥神经保护作用。

关键词:  脑出血, 骨髓细胞, 干细胞移植, 脑源性神经营养因子, 细胞凋亡, 细胞, 培养的, 疾病模型, 动物

Abstract:

 Objective To investigate the neuroprotective effect of bone marrow mesenchymal stem cell (BMMSC) transplantation on collagenase-induced intracerebral hemorrhage (ICH) adult sprague-Dawley (SD) rat model. Methods The collagenase-induced ICH models were constructed by injection of collagenase type Ⅶ into the striatum on the right side stereotaxically. Forty-five healthy male SD rats were selected and then randomly divided into 3 groups of fifteen each, control group, ICH rat model group (model group), BMMSC transplanted ICH group (transplantation group). In transplantation group, BMMSC were transplanted into the perilesional sites 2 h after ICH injury. Modified Neurological Severity Score (mNSS), brain-derived neurotrophic factor (BDNF) immunohistochemical expression, and TUNEL test (cell apoptosis) were assessed at the 1, 3, 7, 14 and 28 d after model-made/transplanted treatment of BMMSC. Results The mNSS score (P = 0.000) and apoptotic cell number (P = 0.000) of rats in different treatment groups at each observation time point showed statistically significant differences. Compared with the control group and the model group, the mNSS score of the transplantation group was lower 28 d after treatment (P < 0.05), showing a decreasing timeliness. The mNSS scores 7, 14 and 28 d after treatment was lower than that 1and 3 d after treatment (P < 0.05). On 1, 3, 7, 14 and 28 d after transplantation, the number of apoptotic cells in the model group and the transplantation group increased (P < 0.05) and reached the peak on 7 d after treatment (all P < 0.05). The number of apoptotic cells on 14 and 28 d was reduced but still higher than that on 1 and 3 d (all P < 0.05). In the transplantation group the expression of BDNF protein was significantly increased, and very few GFP + GFAP and GFP + NeuN positive cells were found in the brain tissue. These results indicated that the transplanted BMMSC had survived in the host brain tissue and with neuronal and glial differentiation. Conclusions Rat ICH model induced by collagenase type Ⅶ is stable for experimental study. The transplanted BMMSC can significantly provide better neuroprotection by increasing BDNF expression and reduce apoptosis.

Key words:  Cerebral hemorrhage, Bone marrow cells, Stem cell transplantation, Brain-derived neurotrophic factor, Apoptosis, Cells, cultured, Disease models, animal