Liao Wang, Jiang Mujun, Li Mei, Jin Congli, Xiao Songhua, Fan Shengnuo, Fang Wenli, Zheng Yuqiu, Liu Jun
Department of Neurology, Sun Yat-sen Memorial Hospital, Sun Yat-sen UniversityGuangzhou, China; Guangdong Province Key Laboratory of Brain Function and Disease, Zhongshan School of Medicine, Sun Yat-sen UniversityGuangzhou, China; Laboratory of RNA and Major Diseases of Brain and Heart, Sun Yat-sen Memorial Hospital, Sun Yat-sen UniversityGuangzhou, China.
Department of Neurology, Bengbu Medical College, The First Affiliated Hospital Bengbu, China.
Front Neurosci. 2017 Feb 23;11:87. doi: 10.3389/fnins.2017.00087. eCollection 2017.
This study aimed to explore the influence of magnesium elevation on fate determination of adult neural progenitor cells (aNPCs) and the underlying mechanism . Adult neurogenesis, which is the generation of functional neurons from neural precursors, occurs throughout life in restricted anatomical regions in mammals. Magnesium is the fourth most abundant ion in mammals, and its elevation in the brain has been shown to enhance memory and synaptic plasticity . However, the effects of magnesium on fate determination of aNPCs, which are vital processes in neurogenesis, remain unknown. NPCs isolated from the dentate gyrus of adult C57/BL6 mice were induced to differentiate in a medium with varying magnesium concentrations (0.6, 0.8, and 1.0 mM) and extracellular signal-regulated kinase (ERK) inhibitor PD0325901. The proportion of cells that differentiated into neurons and glial cells was evaluated using immunofluorescence. Quantitative real-time polymerase chain reaction and Western blot methods were used to determine the expression of β-III tubulin (Tuj1) and glial fibrillary acidic protein (GFAP). The activation of ERK and cAMP response element-binding protein (CREB) was examined by Western blot to reveal the underlying mechanism. Magnesium elevation increased the proportion of Tju1-positive cells and decreased the proportion of GFAP-positive cells. Also, the expression of Tuj1 was upregulated, whereas the expression of GFAP was downregulated. Moreover, magnesium elevation enhanced the activation of both ERK and CREB. Treatment with PD0325901 reversed these effects in a dose-dependent manner. Magnesium elevation promoted neural differentiation while suppressing glial cell differentiation, possibly via ERK-induced CREB activation.
本研究旨在探讨镁离子浓度升高对成年神经祖细胞(aNPCs)命运决定的影响及其潜在机制。成年神经发生是指神经前体细胞产生功能性神经元的过程,在哺乳动物的特定解剖区域终生存在。镁是哺乳动物体内第四丰富的离子,其在脑内浓度升高已被证明可增强记忆和突触可塑性。然而,镁对aNPCs命运决定(神经发生中的关键过程)的影响仍不清楚。从成年C57/BL6小鼠齿状回分离的NPCs在含有不同镁浓度(0.6、0.8和1.0 mM)的培养基以及细胞外信号调节激酶(ERK)抑制剂PD0325901中诱导分化。使用免疫荧光评估分化为神经元和胶质细胞的细胞比例。采用定量实时聚合酶链反应和蛋白质印迹法测定β-III微管蛋白(Tuj1)和胶质纤维酸性蛋白(GFAP)的表达。通过蛋白质印迹检测ERK和环磷酸腺苷反应元件结合蛋白(CREB)的激活情况以揭示潜在机制。镁离子浓度升高增加了Tuj1阳性细胞的比例,降低了GFAP阳性细胞的比例。此外,Tuj1的表达上调,而GFAP的表达下调。而且,镁离子浓度升高增强了ERK和CREB的激活。用PD0325901处理以剂量依赖方式逆转了这些效应。镁离子浓度升高可能通过ERK诱导的CREB激活促进神经分化,同时抑制胶质细胞分化。