Blocking beta 2-adrenergic receptor inhibits dendrite ramification in a mouse model of Alzheimer＇s disease

• Published in: 中国神经再生研究：英文版 2017, Vol.12 (9), p.1499-1506
• Main Author: Qin Wu Jin-xia Sun Xiang-he Song Jing Wang Cun-quan Xiong Fei-xiang Teng Cui-xiang Gao
• Format: Article
• Language: English
• Subjects: Morris水迷宫; β2-肾上腺素能受体; 免疫组织化学染色; 分枝; 小鼠模型; 树突; 淀粉样前体蛋白; 阿尔茨海默病
• ISSN: 1673-5374

Dendrite ramification affects synaptic strength and plays a crucial role in memory. Previous studies revealed a correlation between beta 2-adrenergic receptor dysfunction and Alzheimer＇s disease （AD）, although the mechanism involved is still poorly understood. The current study investigated the potential effect of the selective β2-adrenergic receptor antagonist, ICI 118551 （ICI）, on Aβ deposits and AD-related cognitive impairment. Morris water maze test results demonstrated that the performance of AD-transgenic （TG） mice treated with ICI （AD-TG/ICI） was significantly poorer compared with NaCl-treated AD-TG mice （AD-TG/NaCl）, suggesting that β2-adrenergic receptor blockage by ICI might reduce the learning and memory abilities of mice. Golgi staining and immunohistochemical staining revealed that blockage of the β2-adrenergic receptor by ICI treatment decreased the number of dendritic branches, and ICI treatment in AD-TG mice decreased the expression of hippocampal synaptophysin and synapsin 1. Western blot assay results showed that the blockage of β2-adrener- gic receptor increased amyloid-β accumulation by downregulating hippocampal a-secretase activity and increasing the phosphorylation of amyloid precursor protein. These findings suggest that blocking the β2-adrenergic receptor inhibits dendrite ramification of hippocampal neurons in a mouse model of AD.