GALANIN REMOLDELING IN THE PROGRESSION OF AD

描述(由申请者提供)：当今痴呆症研究的一个关键挑战是 了解阿尔茨海默病(AD)进展过程中退行性和再生性事件的神经生物学机制。这一PPG部分将检验一组假说，旨在更深入地了解与AD患者胆碱能前脑(CBF)神经元存活相关的甘氨酸能神经重塑反应。最近的发现使我们假设，增加的GAL可能对特定的CBF神经元具有神经保护作用，因为神经退行性变在发生GAL重塑的CBF前部最小，轻度认知障碍(MCI)和轻度AD(50)患者的CBF神经元的损失很小(见初步数据)，在缺乏GAL基因的小鼠的CBF前部，CBF神经元减少了35%，GAL促进了培养的感觉神经元的突起生长，GAL和GAL受体在胚胎干细胞中表达，提示了在细胞分化中的作用。本申请测试了一系列假设，即在从MCI到AD的转变过程中，1)Gal重塑增强了与神经保护相关的基因的表达， GAL重塑包括神经生长因子及其受体和特定的GAL受体基因；2)利用Binder博士提供的针对位点特异性tau磷酸化表位的抗体，选择性地稳定包含部位特异性tau磷酸化表位的CBF神经元中与微管形成相关的基因的表达(项目4)；3)GAL重塑与表达GAL mRNA的神经元的数量随着AD的进展有关，或在疾病进展期间每个CBF前神经元的GAL mRNA合成增加，4；利用共聚焦显微镜，在CBF高神经支配的神经元上，GAL突触样突触样结合增加。来自Rush宗教秩序研究的GAL重塑将在临床诊断为无认知损害、MCI和AD的个人中进行评估。分子方面的发现将是 与认知(即陈述性、工作和情景记忆)、注意力测试、病理学(即Braak和Reagan标准、斑块负荷)和诊断类别相关。这些研究将导致旨在减缓AD无情攻击的新的药物治疗。项目3讨论摘要：经修订的申请被视为一项改进。有一个共识是，评价者认识到项目3的工作仍然是相关的，因为没有计划进行机械性调查；实际上，当计划仅限于研究人类患者材料时，这些调查甚至可能是不可能的。AIM 1被认为是项目3中最有趣的方面。对于AIM 2，评价者强烈敦促PL包括开发用于原位杂交研究的三种甘丙氨酸受体的探针。序列是已知的，使得寡核苷酸探针可以像开发甘丙素mRNA的探针的计划一样容易制备。从它们的使用中可以获得大量有价值的信息。

DESCRIPTION (provided by applicant): A crucial challenge in dementia research today is to understand the neurobiologic mechanisms underlying the degenerative and regenerative events which occur during the progression of Alzheimer's disease (AD). This PPG component will examine a set of hypotheses aimed at gaining greater insight into the galaninergic neural remodeling response associated with the survival of cholinergic basal forebrain (CBF) neurons in AD. Recent findings have led us to hypothesize that increased GAL may be neuroprotective for select CBF neurons since neural degeneration is least in the anterior CBF where GAL remodeling occurs, the loss of CBF neurons is minimal in people with mild cognitive impairment (MCI) and mild AD (50) at a point in the disease process where GAL remodeling begins (see Preliminary data), there is a 35% reduction in CBF neurons in the anterior CBF in mice lacking the GAL gene, GAL enhances neurite outgrowth in cultured sensory neurons and GAL and GAL receptors are expressed in embryonic stem cells suggesting a role in cell differentiation. The present application tests a series of hypotheses that during the transition from MCI to AD that 1) GAL remodeling enhances the expression of genes associated with neuroprotection, in anterior CBF neurons including nerve growth factor and its receptors and specific GAL receptor genes; 2) Selectively stabilizes the expression of genes associated with micortublular formation in CBF neurons containing site-specific tau phosphorylation epitopes using antibodies against site-specific tau phosphopeptides provided by Dr. Binder (Project 4); 3) GAL remodeling is associated with an increase in the number of GAL mRNA expressing neurons as AD progresses or alternatively there is an increase in GAL mRNA synthesis per anterior CBF neuron during disease progression, 4; There is an increase in GAL synaptic-like appositions upon anterior CBF hyper innervated neurons using a confocal microscope. GAL remodeling will be evaluated in individuals derived from the Rush Religious Orders Study with a clinical diagnosis of no cognitive impairment, MCI, and AD. The molecular findings will be correlated with cognitive (i.e., declarative, working and episodic memory), attention tests, pathology (i.e., Braak and Reagan Criteria, plaque load) and diagnostic categories. These investigations will lead to novel pharmacological treatments aimed at slowing the relentless onslaught of AD. Summary of the Project 3 Discussion: The revised application is seen as an improvement. There is a consensus that the reviewers recognized the work of Project 3 remains correlative, since no mechanistic investigations are planned; indeed, they may not even be possible when limiting the plan to study of human patient material. Aim 1 was viewed as the most interesting aspect of Project 3. For Aim 2, reviewers strongly urged the PL to include the development of probes to the three galanin receptors for use in the in situ hybridization studies. The sequences are known such that oligonucleotide probes can be as easily prepared as the plan for development of probes for galanin mRNA. A good deal of valuable information could be derived from their use.