中国神经再生研究(英文版) ›› 2014, Vol. 9 ›› Issue (1): 41-50.doi: 10.4103/1673-5374.125328

• 原著:退行性病与再生 • 上一篇    下一篇

Dab2:减轻阿尔茨海默病海马神经元的损伤

  

  • 收稿日期:2013-11-29 出版日期:2014-01-05 发布日期:2014-01-05

Dab2 attenuates brain injury in APP/PS1 mice via targeting transforming growth factor-beta/SMAD signaling

Lei Song1, Yue Gu2, Jing Jie2, Xiaoxue Bai2, Ying Yang2, Chaoying Liu2, Qun Liu1   

  1. 1 Department of Neurology, Norman Bethune First Hospital of Jilin University, Changchun, Jilin Province, China
    2 Department of Respiratory Medicine, Norman Bethune First Hospital of Jilin University, Changchun, Jilin Province, China
  • Received:2013-11-29 Online:2014-01-05 Published:2014-01-05
  • Contact: Qun Liu, M.D., Department of Neurology, Norman Bethune First Hospital of Jilin University, Changchun 130021, Jilin Province, China, songleisl@163.com. Chaoying Liu, Department of Respiratory Medicine, Norman Bethune First Hospital of Jilin University, Changchun, Jilin Province, China, 48580116@qq.com.

摘要:

阿尔茨海默病患者脑内转化生长因子β受体—TβRII极度缺乏,导致TGF-β1/SMADs信号通路传导抑制,从而加重了β淀粉样蛋白的沉积和神经元的损伤。Dab2是一种特异性衔接蛋白,可促进内质体中的TβRⅡ重新循环至膜上而免于降解,从而保证了TGF-β1/SMADs信号通路的有效传导。实验通过腺相关病毒载体使Dab2基因在APP/PS1转基因小鼠海马内过表达,研究Dab2蛋白对阿尔茨海默病疾病模型中TGF-β1/SMADs信号通路的调节作用以及其潜在的神经保护作用。结果显示,APP/PS1小鼠海马内TβRII含量明显低于正常小鼠。过表达Dab2后APP/PS1双转基因阿尔茨海默病小鼠海马内TβRII、p-SMAD2/3的含量显著上调,脑内β淀粉样蛋白的沉积、海马内小胶质细胞的激活,肿瘤坏死因子α和白细胞介素6的表达以及神经元的缺失明显减轻。实验结果证明,Dab2可能通过调节TGF-β1/SMADs信号通路发挥对阿尔茨海默病的神经保护作用。

关键词: TGF-β1, Dab2, 阿尔茨海默病, β淀粉样蛋白, 神经元, SMAD2, SMAD3, 小胶质细胞

Abstract:

Transforming growth factor-beta (TGF-β) type II receptor (TβRII) levels are extremely low in the brain tissue of patients with Alzheimer’s disease. This receptor inhibits TGF-β1/SMAD signaling and thereby aggravates amyolid-beta deposition and neuronal injury. Dab2, a specific adapter protein, protects TβRII from degradation and ensures the effective conduction of TGF-β1/SMAD signaling. In this study, we used an adenoviral vector to overexpress the Dab2 gene in the mouse hippocampus and investigated the regulatory effect of Dab2 protein on TGF-β1/SMAD signaling in a mouse model of Alzheimer’s disease, and the potential neuroprotective effect. The results showed that the TβRII level was lower in APP/PS1 mouse hippocampus than in normal mouse hippocampus. After Dab2 expression, hippocampal TβRII and p-SMAD2/3 levels were significantly increased, while amyloid-beta deposition, microglia activation, tumor necrosis factor-α and interleulin-6 levels and neuronal loss were significantly attenuated in APP/PS1 mouse brain tissue. These results suggest that Dab2 can exhibit neuroprotective effects in Alzheimer’s disease by regulating TGF-β1/SMAD signaling.

Key words: nerve regeneration, transforming growth factor-β1, Dab2, Alzheimer’s disease, amyolid-beta, neuron, SMAD2, SMAD3, microglia, neural regeneration