Vascular-Mediated Neuronal Cell Death Alzheimer's

描述（由申请人提供）：越来越多的数据支持在阿尔茨海默病（AD）大脑中发现血管生成特征的因素和过程的观点。我们已经表明，在AD微血管表达或释放许多炎症，促血管生成蛋白。尽管阿尔茨海默病患者大脑中的促血管生成因子增加，但缺乏血管增强的证据。在我们的模型中，我们假设血管生成过程不会进展到新的血管生长，因为促血管生成因子和抗血管生成因子的不平衡导致血管生成信号中断。在这个项目中，我们验证了AD微血管表达一种致缺氧表型的假设，以及这种脑内皮细胞的异常激活对AD病理的发展很重要。目的1：验证AD患者脑微血管被激活但不能完成血管生成的假设，因为促血管生成因子和抗血管生成因子的不平衡导致血管生成信号流产。从AD患者、年龄匹配的非痴呆对照组、炎症性和非炎症性CMS患者中分离出脑微血管。比较离体血管促血管生成因子和抗血管生成因子的表达，包括凝血酶、VEGF、内皮素-1 TGF-/0、一氧化氮、血栓反应蛋白和β淀粉样蛋白（A¿）。检测信号激酶磷脂酰肌醇-3激酶(PI3K)/Akt、p38激酶、细胞外信号调节激酶（ERK）和c-Jun nh2末端激酶（JNK）的活性。脑切片免疫组织化学用于评估促血管生成蛋白和抗血管生成蛋白与A/？沉积和AD病理。目的2：在阿尔茨海默病动物模型中验证血管生成表型的获得参与阿尔茨海默病病理和认知障碍发病机制的假设。为了确定血管生成表型的获得与疾病发病之间的时间相关性，研究人员在AD转基因小鼠的认知变化和AD病理发生前以及疾病进展过程中的几个年龄阶段，在离体脑微血管中测量了血管生成标志物。使用抗血管生成药物评估血管生成表型和疾病进展之间的因果关系。在行为改变和AD病理发生之前给药这些药物将决定抑制血管生成表型是否会影响疾病的进程。综上所述，Aim 1的数据显示了阿尔茨海默病血管生成变化的临床相关性，Aim 2的结果显示了血管生成表型与疾病进展之间的因果关系，这有力地证明了一种新的阿尔茨海默病治疗方法。这些结果可能是非常令人兴奋的，因为血管生成的脑内皮细胞是一个新的、未开发的治疗靶点，目前有几种抗血管生成药物正在III期临床试验中使用。因此，血管生成抑制剂的临床研究可以在AD患者中快速设计和实施。

DESCRIPTION (provided by applicant): Data are emerging to support the idea that factors and processes characteristic of angiogenesis are found in the Alzheimer disease (AD) brain. We have shown that in AD microvessels express or release many inflammatory, proangiogenic proteins. Despite increases in proangiogenic factors in the AD brain, evidence for increased vascularity is lacking. In our model we hypothesize that the angiogenic process does not progress to new vessel growth because an imbalance of pro- and anti-angiogenic factors results in aborted angiogenic signaling. In this project we test the hypothesis that AD microvessels express an anqiogenic phenotype and that this abnormal activation of brain endothelial cells is important for the development of AD pathology. Aim 1: To test the hypothesis that in AD brain microvessels become activated but fail to complete angiogenesis because an imbalance of pro- and anti-angiogenic factors results in aborted angiogenic signaling. Brain microvessels are isolated from AD patients, age-matched non-demented controls, and patients with inflammatory and non-inflammatory CMS disease. Isolated vessels are compared for expression of pro- and anti-angiogenic factors including thrombin, VEGF, endothelin-1 TGF-/0, nitric oxide, thrombospondin, and amyloid beta (A¿). The activities of signaling kinases phosphatidylinositol-3 kinase (PI3K)/Akt, p38 kinase, extracellular signal-regulated kinase (ERK), and c-Jun NH2-terminal kinase (JNK) are measured. Immunohistochemistry of brain sections is used to assess the spatial correlation of pro- and anti-angiogenic proteins with A/? deposition and AD pathology. Aim 2: To test the hypothesis that acquisition of the angiogenic phenotype contributes to the pathogenesis of AD pathology and cognitive impairment in animal models of AD. To determine the temporal association between acquisition of the angiogenic phenotype and the onset of disease, markers of angiogenesis are measured in isolated brain microvessels obtained from AD transgenic mice before the onset of cognitive changes and AD pathology and at several ages during disease progression. A causal link between the angiogenic phenotype and disease progression is evaluated using antiangiogenic drugs. Administration of these drugs to animals prior to the onset of behavioral changes and AD pathology will determine whether inhibiting the angiogenic phenotype affects the course of disease. Taken together, data from Aim 1 showing the clinical relevance of angiogenic changes in AD and results from Aim 2 demonstrating a causal link between the angiogenic phenotype and disease progression would argue strongly for a new therapeutic approach in AD. These results could be very exciting because the angiogenic brain endothelial cell is a novel, unexplored therapeutic target, and several antiangiogenic drugs are currently in use in Phase III clinical trials. Thus, clinical studies with angiogenesis inhibitors could be rapidly designed and implemented in AD patients.