Cyclohexanehexol Therapy in Transgenic Models of Alzheimer's Disease

描述(申请人提供)：含有β淀粉样蛋白(A？)和带有磷酸化tau的神经原纤维缠结(NFT)的老年斑是阿尔茨海默病(AD)的病理特征。ASS多肽，尤其是A？42，被认为在AD的发病机制中起关键作用。我们发现布洛芬是一种非类固醇抗炎药(NSAID)，具有降低A42的作用，可以减少Ass沉积、NFT和在一种新的三重转基因AD小鼠模型(3xTg-AD)中的认知功能下降，该模型同时出现老年斑和NFT。R-氟比洛芬是非类固醇抗炎药氟比洛芬的一种对映体，它降低了A？42，但缺乏环氧合酶抑制，减少了AD转基因小鼠的A？负担，目前正在进行第三期AD临床试验。我们发现口服R-氟比洛芬在转基因小鼠脑中具有良好的耐受性和可检测性。肌醇是环己醇的一种异构体，可以抑制A？寡聚体的形成，当口服给AD转基因小鼠时，可以减少A？的聚集和沉积，并减少认知能力的下降。重要的是，肌醇是无毒的，通常存在于大脑中，可以通过磁共振波谱(MRS)检测到。我们建议的一个主要目标是使用3xTg-AD模型和双转基因PSAPP模型，该模型不会发生NFT，但会形成更广泛和快速的A？沉积，以评估肌醇和环己醇的第二个异构体-肌醇单独和与R-氟比洛芬联合使用的预防和治疗效果。我们假设，环己己醇将通过减少A？42的寡聚化来减少A？的神经毒性，并改善转基因小鼠的神经化学特征和认知能力，与R-氟比洛芬联合治疗将具有附加治疗效果，R-氟比洛芬通过完全不同的作用机制减少A？的沉积。我们的初步研究表明，我们可以使用MRS检测到使用肌醇治疗的转基因小鼠大脑中肌醇水平增加3-4倍，而且这种治疗改善了两种转基因小鼠的长期记忆。使用肌醇的初步研究表明，它在小鼠身上耐受性很好。本研究的目的是：1)评估双转基因和三转基因小鼠的代谢、组织病理学、生化和认知特征，以及在病理建立之前或之后口服肌醇的情况。将使用对A？没有影响的肌醇作为对照。将使用放射臂水迷宫研究行为效应，并将使用蛋白质印迹、ELISA、MRS和定量免疫细胞化学来研究生化和组织学效应；2)评估R-氟比洛芬与AIM 1中定义的最有效的环己醇化合物联合治疗是否具有相加治疗效果，使用AIM 1中定义的参数。我们还将在指定年龄的小鼠上进行系列MRS，以评估联合治疗对代谢谱的纵向影响。我们建议的研究将探索结合最先进的成像、神经病理和生化技术的诊断方法和潜在的治疗方法，以帮助设计预防和治疗AD的策略。与公共卫生相关：阿尔茨海默病是一种持续发展的、总是致命的疾病，影响着数以百万计的美国老年人，每年花费美国政府数十亿美元的医疗费用。在这项提议中，我们将使用表达人类阿尔茨海默氏症基因的转基因小鼠模型来研究我们如何治疗由于大脑中异常蛋白质积累而导致的病理。我们将在活着的小鼠身上使用治疗剂，用最先进的成像技术监测疾病的进展，并将结果与免疫组织化学结果相关联。这些研究将为未来开发更好的检测和治疗阿尔茨海默病的方法奠定重要基础。

DESCRIPTION (provided by applicant): Senile plaques that contain beta amyloid (A¿) and neurofibrillary tangles (NFT) with phosphorylated tau are the pathological hallmarks of Alzheimer's disease (AD). Ass peptides, especially A¿42, are thought to play a key role in the pathogenesis of AD. We found that ibuprofen, a non-steroidal anti-inflammatory drug (NSAID) with A¿42- lowering effects, reduces Ass deposition, NFT and cognitive decline in a novel triple transgenic mouse model of AD (3xTg-AD) that develops both senile plaques and NFT. R-flurbiprofen, an enantiomer of the NSAID flurbiprofen that lowers A¿42 but lacks cyclooxygenase inhibition reduces A¿ burden in AD transgenic mice and is currently being tested in a phase III AD clinical trial. We found that oral R-flurbiprofen is well tolerated and detectable in transgenic mouse brain. Scyllo-inositol, an isomer of cyclohexanahexol, inhibits A¿ oligomers formation and, when orally administered to AD transgenicyc mice, reduces A¿ aggregation and deposition, and reduces cognitive decline. Importantly, scyllo-inositol is nontoxic, normally present in brain, and can be detected by magnetic resonance spectroscopy (MRS). A major goal of our proposal is to use the 3xTg-AD model and a double transgenic PSAPP model, that does not develop NFT but develops more widespread and rapid A¿ deposition, to assess the prophylactic and therapeutic effects of scyllo-inositol and a second isomer of cyclohexanahexol, myo-inositol, alone and in combination with R-flurbiprofen. We hypothesize that cyclohexanehexols will reduce the neurotoxicity of A¿ and improve the neurochemical profile and cognitive performance of transgenic mice by decreasing the oligomerization of A¿42 and that combination therapy with R-flurbiprofen, which reduces A¿ deposition through an entirely different mechanism of action, will have an additive therapeutic effect. Our preliminary studies show that we can detect a 3-4 fold increase in scyllo-inositol levels in the brains of transgenic mice treated with scyllo-inositol using MRS and that the treatment improves long-term memory in both transgenic mouse models. Preliminary studies using myo-inositol show that it is well tolerated in mice. The aims of the present proposal are: 1) To assess, the metabolic, histopathological, biochemical and cognitive profiles of double and triple transgenic mice treated with oral scyllo- or myo-inositol either before or after pathology has been established. Chiro-inositol, which has no effects on A¿, will be used as a control. Behavioral effects will be studied using radial arm water maze and biochemical and histological effects will be studied using western blot, ELISA, MRS and quantitative immunocytochemistry; 2) To assess whether combination therapy with R-flurbiprofen and the most effective cyclohexanahexol compound defined in aim 1 will have additive therapeutic effects using the parameters defined in aim 1. We will also perform serial MRS on mice at defined ages to assess the longitudinal effects of combination therapy on metabolic profiles. Our proposed research will investigate diagnostic methods and potential therapeutics integrating state of the art imaging, neuropathological and biochemical techniques to help design strategies to prevent and treat AD. PUBLIC HEALTH RELEVANCE: Alzheimer's disease is a relentlessly progressive, invariably fatal, disorder affecting millions of older Americans and costing the U.S. government billions of dollars in health care annually. In this proposal we will use a genetically modified mouse model that expresses human Alzheimer genes to study how we can treat the pathologies that are due to the accumulation of abnormal proteins in the brain. We will use therapeutic agents in living mice and monitor the disease progression with state-of-the-art imaging techniques and correlate findings with immunohistochemical findings. These studies will lay important groundwork for the future development of better approaches to detect and treat Alzheimer's disease.