脂肪来源干细胞移植促进大鼠脑梗死周边区皮质结直肠癌缺失蛋白(DCC)和神经丝蛋白200(NF-200)的表达

Transplanted adipose-derived stem cells promote the expression of deleted in colorectal cancer(DCC) and neurofilament-200(NF-200) in peri-infarct cortex of rats

目的研究脂肪来源干细胞(ADSC)移植对大鼠脑梗死周边区皮质中结直肠癌缺失蛋白(DCC)和神经丝蛋白200(NF-200)表达的影响。方法 SD大鼠随机分为假手术组、模型组和ADSC组。采用改良Longa线栓法制备大鼠大脑中动脉闭塞脑梗死模型。ADSC组大鼠于造模后24 h经颈动脉注射入50μL用PKH-26标记的ADSC悬液(含约2×10^6个细胞),模型组大鼠注射等剂量的生理盐水。于造模后第7、14天,在荧光显微镜下观察脑组织中ADSC的迁移情况,采用Western blot法检测脑梗死周边区皮质DCC、 NF-200的蛋白水平,免疫荧光法检测脑梗死周边区皮质中DCC、NF-200的表达和分布。结果 ADSC组大鼠脑组织中可检测到PKH-26标记的ADSC,且大部分位于脑梗死周边区皮质中。造模后第7、14天,模型组DCC的表达均高于假手术组,而NF-200的表达均低于假手术组;ADSC组DCC和NF-200的表达在各个时间点均高于模型组。在梗死周边区皮质, DCC主要表达于NF-200阳性的神经元轴突中。结论经颈动脉移植的ADSC可以迁移至脑梗死周边区皮质,并可能通过促进该区域DCC、NF-200的表达,从而强化神经轴突的再生修复。

Objective To investigate the effects of adipose-derived stem cells(ADSCs) transplantation on the expression of deleted in colorectal cancer(DCC) and neurofilament-200(NF-200) in peri-infarct cortex of rats. Methods SD rats were randomly divided into sham group, model group and ADSCs group. The rat model of middle cerebral artery occlusion(MCAO) was established with the modified Longa’s method. Twenty-four hours after MCAO, 50 μL of cell suspension containing about 2×10^6 PKH-26-labeled ADSCs was injected into the carotid artery of rats in the ADSCs group, and the same dose of saline was given to the rats in the model group. Day 7 and 14 after MCAO, the migration of ADSCs in rat brains was observed under a fluorescence microscope, and the protein levels of DCC and NF-200 in the peri-infarct cortex were measured by Western blot analysis and the expression and distribution of DCC and NF-200 were detected by immunofluorescent histochemistry. Results PKH-26-labeled ADSCs were observed in the rat brains of ADSC group, and most of them were located in the peri-infarct cortex. At 7 and 14 days after MCAO, the expression of DCC in the model group was higher than that in the sham group, while the expression level of NF-200 was lower. Besides, the expression of DCC and NF-200 in the ADSC group was both higher than that in the model group. In the peri-infract cortex, DCC was mainly expressed in NF-200-positive neuronal axons. Conclusion The ADSCs can migrate to the peri-infarct cortex after transplantation via carotid artery, and may strengthen the axonal regeneration and repairment by promoting the expression of DCC and NF-200 in this region.