Antisense Oligonucleotides targeting APP to prevent neurodegeneration in models of Down Syndrome and Alzheimer's disease

靶向 APP 的反义寡核苷酸可预防唐氏综合症和阿尔茨海默病模型中的神经变性

• 批准号: 10092057
• 负责人: William C Mobley
• 金额: $ 73.21万
• 依托单位: UNIVERSITY OF CALIFORNIA, SAN DIEGO
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-04-15 至 2024-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10092057
• 关键词: Age; Alzheimer' s Disease; Alzheimer' s disease model; Amyloid; Amyloid beta-42; Amyloid beta-Protein Precursor; Antisense Oligonucleotides; Atrophic; Benchmarking; Blinded; C-terminal; Central Nervous System Diseases; Chromosome 21; Code; Cognition; Cognitive deficits; Collaborations; Complex; Dementia; Deposition; Disease; Dose; Down Syndrome; Drug Kinetics; Early Endosome; Elderly; Endosomes; Gene Expression; Gene Proteins; Genes; Genome; Goals; Guanosine Triphosphate Phosphohydrolases; Human Amyloid Precursor Protein; In Vitro; Injections; Intracellular Transport; Length; Measures; Mediating; Messenger RNA; Modeling; Mus; Nerve Degeneration; Neurofibrillary Tangles; Neurons; Outcome; Pharmacodynamics; Phenotype; Population; Property; Proteins; RNA; RTN4 gene; Sampling; Senile Plaques; Signal Transduction; Specificity; Spinal Muscular Atrophy; Structure; Synapses; System; Testing; Therapeutic; Tissues; Toxic effect; Transgenic Organisms; Treatment Efficacy; Treatment Protocols; Trisomy; Vertebral column; age related neurodegeneration; basal forebrain; base; cerebral amyloidosis; cholinergic; design; entorhinal cortex; improved; in vivo; inorganic phosphate; locus ceruleus structure; mouse model; mutant mouse model; neuropathology; neurotrophic factor; pharmacokinetics and pharmacodynamics; phosphorothioate; prevent; protein expression; tau Proteins; tau-1; therapeutic evaluation; trafficking

We aim to prevent Alzheimer disease (AD) in DS (trisomy 21) (AD-DS). Using antisense oligonucleotides (ASOs), we will selectively target RNA for the amyloid precursor protein (APP) in mouse models of AD-DS (Dp16) and AD/cerebral amyloidosis (Line 41). The therapeutic premise is based on: 1) increased APP gene dose is necessary for AD-DS. As replicated in models of AD-DS, normalizing APP dose eliminated: a) age-related neurodegeneration in locus coeruleus and the basal forebrain complex, b) hyper- phosphorylation of Tau, and c) enlargement of early endosomes; 2) pointing to a mechanism by which increased APP gene dose acts, increased full-length APP (fl-APP), its 99 residue C-terminal fragment (C99) and Aβ42 each increased Rab5 activity, thus enlarging early endosomes, disrupting endosomal trafficking of neurotrophic signals, and causing atrophy of BFCNs; 3) therefore, reducing levels of these APP products is a rational approach to preventing or lessening the impact of increased APP gene dose in AD-DS, including effects on endosomes. ASOs have recently been shown to safely and effectively treat CNS disorders. Indeed, FDA approval for ASOs in Spinal Muscular Atrophy motivates trials of ASOs in other CNS diseases. In preliminary studies we showed that intracerebroventricular (ICV) injection of ASOs targeting mouse and human APP (i.e. mAPP-ASOs and hAPP-ASOs) reduced APP mRNA and protein levels. Using mouse models of AD-DS and AD/cerebral amyloidosis we will test the therapeutic hypothesis that APP-ASOs will selectively reduce the levels of APP mRNA and its products to prevent and/or lessen neurodegeneration. The mechanistic hypothesis is that APP-ASOs will normalize endosomal structure and function, neurotrophin signaling and trafficking, and improve cognition. Using defined GO/NOGO criteria as a guide, we will pursue these Specific Aims: 1. To investigate newly designed APP-ASOs in vitro for efficacy and target specificity. Using an existing mAPP-ASO as benchmark, additional mAPP-ASOs will be designed to increase potency for targeting APP mRNA and its products and normalizing endosome size. 2. To establish optimal APP-ASO doses and dose-intervals based on empirically defined in vivo pharmacokinetic (PK) and pharmacodynamic (PD) properties. We will define effective, non-toxic doses and treatment intervals for advancement of mAPP-ASOs and hAPP-ASOs to in vivo studies in Aim 3. In the Dp16 model, we will target a ~33% reduction of mAPP RNA, i.e. to 2N values; in Line 41 mice we will target a 50% reduction. Aim 3. To investigate in vivo APP-ASO efficacy in ameliorating neurodegeneration and normalizing endosomal phenotypes. To test the therapeutic hypothesis, we will ask if APP-ASOs given before degeneration in Dp16 mice and plaque deposition in Line 41 mice prevent these changes. Next, we will ask if degeneration in Dp16 mice can be reversed by APP-ASO treatment. The mechanistic hypothesis will be informed by whether or not APP-ASO reductions in degeneration are correlated with normalization of endosomal phenotypes.

我们的目标是预防DS（21三体）（AD-DS）中的阿尔茨海默病（AD）。使用反义寡核苷酸 （ASO），我们将在AD-DS（Dp 16）小鼠模型中选择性靶向淀粉样前体蛋白（APP）的RNA 和AD/脑淀粉样变性（第41行）。治疗前提是基于：1）增加APP基因剂量， 这是AD-DS的必要条件。如在AD-DS模型中复制的，消除了标准化APP剂量：a）年龄相关的 蓝斑和基底前脑复合体中的神经变性，B）Tau的过度磷酸化，和c） 早期内体扩大; 2）指出APP基因剂量增加的作用机制，增加全长 APP（fl-APP）、其99个残基的C-末端片段（C99）和Aβ42均增加Rab 5的活性，从而使Rab 5的活性提前增大， 内体，破坏神经营养信号的内体运输，并引起BFCN萎缩; 3） 因此，减少这些APP产品的水平是预防或减轻 AD-DS中APP基因剂量增加，包括对内体的影响。ASO最近被证明可以安全地 有效治疗中枢神经系统疾病。事实上，FDA批准ASO用于脊髓性肌萎缩症的试验 其他中枢神经系统疾病中的ASO。在初步研究中，我们发现侧脑室（ICV）注射 靶向小鼠和人APP的ASO（即mAPP-ASO和hAPP-ASO）减少APP mRNA和蛋白质 程度.使用AD-DS和AD/脑淀粉样变性的小鼠模型，我们将测试治疗假设 APP-ASO将选择性地降低APP mRNA及其产物的水平，以预防和/或减轻 神经变性机制假说是APP-ASO将使内体结构正常化， 功能，神经营养因子信号传导和运输，并改善认知。使用定义的GO/NOGO标准作为 作为指导，我们将追求这些具体目标：1。在体外研究新设计的APP-ASO的疗效， 目标专一性使用现有mAPP-ASO作为基准，将设计额外的mAPP-ASO，以 增加靶向APP mRNA及其产物效力并使内体大小正常化。2.建立 基于经验定义的体内药代动力学（PK）的最佳APP-ASO剂量和剂量间隔， 药效学（PD）特性。我们将确定有效的、无毒的剂量和治疗间隔， 在目的3中，将mAPP-ASO和hAPP-ASO推进到体内研究。在Dp 16模型中，我们将针对 mAPP RNA减少约33%，即减少至2N值;在41系小鼠中，我们的目标是减少50%。目标3.到 研究APP-ASO在改善神经变性和使内体正常化中体内功效 表型为了检验治疗假设，我们将询问在Dp 16中变性之前给予APP-ASO是否 41系小鼠中的斑块沉积阻止了这些变化。接下来，我们将询问Dp 16中的变性是否 小鼠可以通过APP-ASO治疗逆转。机械假说将被告知是否 变性中的APP-ASO减少与内体表型的正常化相关。