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

描述(申请人提供)：阿尔茨海默病(AD)是一种痴呆症，在美国有400万老年人患有，预计到2050年这一数字将翻两番。这种神经退行性疾病在65岁的人中有4%的人会受到影响，在85岁的人中有多达40%的人会受到影响，每年的损失超过1000亿美元。迫切需要有效的治疗干预措施，以预防、推迟发病年龄或缓解这种痴呆的病程。表达人类AD基因的转基因(TG)小鼠，如淀粉样前体蛋白(APP)、早老素(PS)、微管蛋白tau、β-淀粉样裂解酶-1(BACE-1)和α-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。在具体目标1中，我们的目标是通过建立这些范例与人类AD受试者之间的生化相似和差异程度，更好地了解几种TG小鼠模型的优点和局限性。在特定目标2中，对AD患者抗A主动免疫和被动免疫后残留的可溶性和沉淀性A进行灰质、白质和脑血管的定量和定性评价，以评价免疫对A动力学的影响及其对AD病程的临床影响。在特定的目标3中，将测定AD和非痴呆对照组的脑微粒体、线粒体和脂筏脑部分中保留的APP和A肽，以更好地了解神经元和神经胶质参与AD的病理生理学的作用。为了实现这三个目标，将采用涉及密度和亲和力梯度、共振剂、多层析分离、氨基酸分析、肽序列、质谱学、生物信息学数据库、免疫分析和Western blotting的物理化学技术。建议的研究将有助于：1)帮助准确解释TG小鼠的实验反应，2)有助于在分子水平上阐明抗-A免疫的直接和间接影响，以及3)发现膜保留的APP/A‘多肽的病理后果，而不仅仅是可溶性A和沉积的淀粉样蛋白。更全面地了解AD的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来预防AD或提高AD患者的生活质量。 公共卫生意义：500多万美国人已经患有阿尔茨海默氏症，这一数字预计到2050年将翻两番，这使得开发有效的补救干预措施来预防、推迟这种毁灭性痴呆症的发病或减缓其发展成为全国的当务之急。我们今天既不知道阿尔茨海默病的病因，也没有治愈阿尔茨海默病的方法，但对人脑和动物模型进行细致的化学研究将有助于阐明阿尔茨海默病的基本分子基础，并揭示人类大脑在这种疾病发展过程中发生的精确病理变化。这些知识将为开发下一代药物干预措施提供必要的基础，这些干预措施将预防阿尔茨海默病或提高痴呆症患者的生活质量。

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.