APP/AB/Tau biochemistry in transgenic mice, familial and sporadic AD

描述（由申请人提供）：阿尔茨海默病（AD）是一种影响美国400万老年人的痴呆症，预计到2050年这一数字将翻两番。这种神经退行性疾病在65岁的人群中占4%，在85岁的人群中占40%，每年花费超过1000亿美元。迫切需要有效的治疗干预措施，以预防、延迟发病年龄或缓解这种痴呆症的病程。转基因（Tg）小鼠表达人类AD基因，如淀粉样蛋白前体蛋白（APP）、早老素（PS）、微管蛋白tau、淀粉样蛋白切割酶-1 （BACE-1）和a-突触核蛋白，为研究这些神经病理疾病的发病机制和治疗效果提供了工具。在Specific Aim 1中，我们的目标是通过建立这些范式与人类AD受试者之间生化相似性和差异性的程度，更好地了解几种Tg小鼠模型的优势和局限性。在Specific Aim 2中，对AD患者主动和被动免疫后的可溶性和沉积性A¿在灰质、白质和脑血管系统中进行定量和定性评估，以评估免疫对A¿动力学的影响及其对AD病程的临床影响。在Specific Aim 3中，将测定AD和非痴呆对照者脑微粒体、线粒体和脂质筏脑部分中保留的APP和A¿肽，以更好地了解神经元和神经胶质参与AD病理生理的作用。为了实现这三个目标，将实施物理化学技术，包括使用密度和亲和梯度、混沌剂、多重色谱分离、氨基酸分析、肽测序、质谱、生物信息学数据库、免疫测定和Western blotting。提出的研究将：1)有助于准确解释Tg小鼠的实验反应，2)有助于在分子水平上阐明抗A¿免疫的直接和间接作用，3)发现膜保留APP/ A¿肽的病理后果，除了可溶性A¿和沉积的淀粉样蛋白。更全面地了解阿尔茨海默病分子表型及其临床反应将有助于发现和应用有效的治疗方法，从而预防阿尔茨海默病或提高阿尔茨海默病患者的生活质量。

DESCRIPTION (provided by applicant): Alzheimer's disease (AD) is a dementia that affects 4 million elderly individuals in the USA and this number is projected to quadruple by 2050. This neurodegenerative disorder strikes 4% of individuals at 65 years of age and as many as 40% of those at age 85 at a cost of over $100 billion annually. There is an urgent need for effective therapeutic interventions that may prevent, delay the age of onset or relent the course of this dementia. Transgenic (Tg) mice expressing human AD genes such as amyloid-¿ precursor protein (APP), presenilin (PS), the microtubule protein tau, ¿-amyloid cleaving enzyme-1 (BACE-1), and a-synuclein have provided tools to investigate both the pathogenesis and the efficacy of treatments for these neuropathological disorders. Our goal, in Specific Aim 1, is to better understand the strengths and limitations of several Tg mice models by establishing the degree of biochemical similarities and differences between these paradigms and human AD subjects. In Specific Aim 2, soluble and deposited A¿ remaining after anti- A¿ active and passive immunizations of AD patients will be quantitatively and qualitatively assessed in gray and white matter and cerebral vasculature to evaluate the effects of immunization on A¿ dynamics and its clinical impact on the course of AD. In Specific Aim 3, the APP and A¿ peptides retained in the brain microsomal, mitochondrial and lipid raft brain fractions in AD and non-demented controls will be determined to better understand the role of neuronal and glial participation in the pathophysiology of AD. To achieve these three objectives physicochemical techniques involving the use of density and affinity gradients, chaotropic agents, multiple chromatographic separations, amino acid analysis, peptide sequencing, mass spectrometry, bioinformatics data bases, immunoassays and Western blotting will be implemented. The proposed studies will: 1) aid in the accurate interpretation of Tg mouse experimental responses, 2) help to elucidate at the molecular level the direct and indirect effects of anti- A¿ immunization and 3) discover the pathological consequences, beyond soluble A¿ and deposited amyloid, of membrane-retained APP/ A¿ peptides. A more complete understanding of AD molecular phenotypes and their clinical responses will aid in the discovery and application of efficacious treatments that will prevent AD or enhance the quality of life of AD patients. PUBLIC HEALTH RELEVANCE: More than 5 million Americans already suffer from Alzheimer's disease and this number is expected to quadruple by the year 2050, making the development of effective remedial interventions to prevent, delay the onset or slow the progression of this devastating dementia a national imperative. We know neither the cause nor posses a means to cure AD today, but meticulous chemical studies of human brains and animal models will help to elucidate the fundamental molecular basis of Alzheimer's disease and reveal the precise pathological changes that occur in the human brain during the development of this disease. This knowledge will provide the essential bases for the development of the next generation of medicinal interventions that will prevent Alzheimer's disease or enhance the quality of life of individuals with this dementia.