Astrocytic Calcineurin and Connexin43 Gap Junctions in Alzheimer's Disease

描述(申请人提供)：作为影响超过520万人的第六大死因，阿尔茨海默病(AD)正在成为一种健康危机。令人失望的是，之前的临床试验显示，在找到治疗这种毁灭性疾病的方法方面收效甚微。因此，探索新的和可替代的分子靶标是至关重要的。这项拟议的项目将测试最重要的假设，即钙调神经磷酸酶(CN)和连接蛋白43(Cx43)的相互作用在AD进展过程中扰乱星形胶质细胞的缝隙连接(GJ)连接，导致神经功能的有害变化。该项目将使用一系列AD模型系统，包括人类海马区标本、APP/PS1转基因小鼠和大鼠原代星形胶质细胞培养，使用多学科方法来研究这一假说。除了优秀的模型系统外，该项目还将使用各种尖端技术，包括荧光共振能量转移(FRET)、腺相关病毒(AAV)介导的基因传递和切片电生理学。主要的假说将通过三个独立的具体目标进行检验，这三个目标是：使用FRET和免疫共沉淀(Co-IPs)等技术检验CN与Cx43在AD进展过程中相互作用的假说；使用染料偶联和Western印迹等技术检验β淀粉样蛋白(A-beta)以CN依赖的方式破坏缝隙连接(GJ)偶联的假说；使用主动回避范式和技术如染料偶联、Western印迹和切片电生理学等认知措施检验CN/Cx43相互作用破坏AD小鼠模型GJ偶联和神经功能的假说。该项目不仅在神经科学研究方面提供了卓越的培训，还将为AD的潜在新治疗靶点提供极其有价值的信息。

DESCRIPTION (provided by applicant): As the sixth leading cause of death that affects over 5.2 million people, Alzheimer's disease (AD) is becoming a health crisis. To much disappointment, previous clinical trials have shown little success in finding a treatment for this devastating disease. Thus, it is critical that new and alternative molecular targets be explored. The proposed project will test the overarching hypothesis that calcineurin (CN) and connexin43 (Cx43) interactions disrupt gap junction (GJ) coupling in astrocytes during the progression of AD leading to detrimental changes in neurologic function. This project will use a multi-disciplinary approach to investigate the hypothesis using an array of AD model systems, including human hippocampal specimens, APP/PS1 transgenic mice, and rat primary astrocyte cultures. In addition to the excellent model systems, this project will use a variety of cutting-edge techniques, including fluorescence resonance energy transfer (FRET), adeno-associated virus (AAV) - mediated gene delivery, and slice electrophysiology. The overarching hypothesis will be examined through three independent specific aims which are as follows: to test the hypothesis that CN interacts with Cx43 during the progression of AD using techniques such as FRET and co-immunoprecipitations (Co-IPs); to test the hypothesis that beta amyloid (A-beta) disrupts gap junction (GJ) coupling in a CN-dependent manner using techniques such as dye coupling and Western blot; to test the hypothesis that CN/Cx43 interactions disrupt GJ coupling and neurologic function in a mouse model of AD using cognitive measures such as the active avoidance paradigm and techniques such as dye coupling, Western blot, and slice electrophysiology. This project not only provides superior training in neuroscience research, but also will provide extremely valuable information into a potential new therapeutic target for AD.