三七总皂苷对脑缺血再灌注大鼠神经血管单元的影响

Abstract: Objective To investigate the effect of panax notoginseng saponins (PNS) on the neurovascular unit (NVU) of the brain tissue around the ischemic focus in rats after cerebral ischemia reperfusion (CIR). Methods The model of focal middle cerebral artery occlusion (MCAO) was established by the suture method. The neurological function scores of rats in each group were detected 4 hours after the operation according to the Longa scoring standard, and then each group was intervened, and the neurological function scores were carried out at 24 hours, 72 hours, 7 days and 3 weeks after ischemia reperfusion respectively. The expression changes of neuronal nuclear antigen (NeuN), glial fibrillary acidic protein (GFAP) and laminin (LN) related to each component of NVU were detected by Western blotting. The ultrastructural changes of NVU in the brain tissue around the ischemic focus of rats in each group at different time points were observed under a transmission electron microscope. Results Compared with the model group, the neurological function scores of rats in the treatment group gradually improved. Compared with the model group, the expression levels of NeuN, GFAP and LN in the treatment group gradually increased, and the differences in the expressions of NeuN and LN at 7 days and 3 weeks were statistically significant (P<0.05), and the differences in the expression level of GFAP at 72 hours, 7 days and 3 weeks compared with the model group were statistically significant (P<0.05). Electron microscope observation showed that the pathological morphological damage of the ultrastructure of NVU in the brain tissue of rats in the treatment group at 24 hours, 72 hours, 7 days and 3 weeks after reperfusion was significantly alleviated compared with that in the model group at the same time points. Conclusion It is indicated that PNS promotes the repair of neurons, glial cells and microvessels of NVU after cerebral ischemia through integration, improves the symptoms of neurological function deficit, and has a protective effect on cerebral ischemia, and its mechanism may be related to the up-regulation of the protein expressions of GFAP, NeuN and LN after cerebral ischemia.

摘要:目的 探讨三七总皂苷（panax notoginseng saponins, PNS）对脑缺血再灌注（cerebral ischemia reperfusion, CIR）后大鼠缺血灶周边脑组织神经血管单元（neurovascular unit, NVU）的影响。方法 采用线栓法制作局灶性大脑中动脉闭塞（middle cerebral artery occlusion, MCAO）模型。采用Longa法评分标准检测各组大鼠术后4 h神经功能评分，随之各组进行干预，分别在缺血再灌注后24 h、72 h、7 d、3 w进行神经功能评分。应用蛋白质印迹法检测NVU各组分相关的神经核抗原（neuronal nuclear antigen, NeuN）、胶质纤维酸性蛋白（glial fibrillary acidic protein, GFAP）和层粘连蛋白（laminin, LN）的表达变化。透射电镜下观察各组大鼠缺血灶周边脑组织不同时间点的NVU超微结构变化。结果 治疗组与模型组相比，大鼠神经功能评分逐渐改善。与模型组相比，治疗组NeuN、GFAP、LN的表达量逐渐升高，其中7 d、3 w的NeuN、LN表达差异具有统计学意义（P<0.05），GFAP表达量在72 h、7 d、3 w与模型组相比差异有统计学意义（P<0.05）。电镜观察发现再灌注24 h、72 h、7 d、3 w治疗组大鼠脑组织NVU超微结构的病理形态损伤均较同时间点模型组明显减轻。结论 表明PNS通过整合促进脑缺血后NVU的神经元、胶质细胞和微血管的修复，改善神经功能缺损症状，对脑缺血具有保护作用，其机制可能与上调脑缺血后GFAP 、NeuN、LN蛋白表达有关。