山茱萸拮抗线粒体缺陷致神经细胞微管及微管相关蛋白表达异常

目的观察中药山茱萸水提液对线粒体呼吸链复合体IV(即细胞色素C氧化酶)抑制剂叠氮钠(NaN3)致神经细胞骨架系统损伤的拮抗作用,探讨山茱萸在防治阿尔采末病中的机制。方法山茱萸水提液(0.125～8g生药·L-1)分别与SH-SY5Y人神经母细胞瘤细胞及原代培养新生大鼠海马神经元共孵育24～48h,加入64mmol·L-1叠氮钠作用4～6h,MTT、LDH法测定细胞存活率,激光共聚焦显微镜观察细胞微管结构及微管相关蛋白表达的变化。结果1～4g·L-1山茱萸能明显拮抗叠氮钠致神经细胞存活率下降;使损伤的微管结构基本恢复正常,微管相关蛋白表达增加,尤以突起内最为明显。结论中药山茱萸能明显拮抗线粒体缺陷致神经细胞损伤,其机制与保护细胞骨架系统有关,对于防治阿尔采末病等神经退行性疾病有一定应用前景。

Effect of Chinese herb cornus on expressions of microtubule and microtubule-associated proteins in nerve cells damaged by mitochondrial deficiency

Aim In order to study the protective effect of Chinese herb cornus on cytoskeleton system of nerve cells damaged by sodium azide, a specific inhibitor of cytochrome C oxidase(COX), and its potential application in Alzheimers disease(AD) therapy. Methods SH-SY5Y human neuroblastoma cells or primary cultured hippocampal neurons of newborn rats were incubated with water extract of cornus from 0.125~8 g·L-1 dried medicinal herb for 24~48 h, then exposed to 64 mmol·L-1 sodium azide for 4~6 h. Cell viability was measured by MTT and LDH methods; cell morphology, immunofluorecence-stained cellular microtubules and microtubule-associated proteins (MAPs) were observed by confocal microscopy. Results Cornus (1~4 g·L-1) antagonized the decrease of cell viability of SH-SY5Y human neuroblastoma cells and primary cultured hippocampal neurons induced by sodium azide. After exposed to 64 mmol·L-1 sodium azide for 4~6 h, the processes of cells retracted, synapses disappeared, axons were shortened under contrast microscope. Meanwhile, microtubles were disassembled and became disorderly; expressions of microtubule-associated proteins were also reduced especially in the processes observed by confocal microscopy. Cornus (1~4 g·L-1) improved the morphology of neurons, the structure of microtubules and expressions of microtubule-associated proteins significantly. Conclusion Chinese herb cornus antagonizes the cytoskeleton injury of nerve cells induced by mitochondrial deficiency. The pharmacological mechanism of this herb is related with the protection of microtubles assembly and microtubule-associated proteins production, so Chinese herb cornus will play the potential role in treating Alzheimers disease and other neurodegenerative diseases.