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: 10334410
• 负责人: William C Mobley
• 金额: $ 70.2万
• 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/10334410
• 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.

我们的目标是使用反义寡核苷酸预防 DS（21 三体）（AD-DS）中的阿尔茨海默病 (AD)。 (ASO)，我们将在 AD-DS (Dp16) 小鼠模型中选择性靶向淀粉样前体蛋白 (APP) 的 RNA AD/脑淀粉样变性（第41行）的治疗前提是：1）增加APP基因剂量。 正如 AD-DS 模型中所复制的那样，标准化 APP 剂量消除了：a) 与年龄相关的。 蓝斑和基底前脑复合体的神经变性，b) Tau 过度磷酸化，c) 2) 指出了增加 APP 基因剂量的作用机制，增加了全长 APP (fl-APP)、其 99 个残基 C 端片段 (C99) 和 Aβ42 均增加 Rab5 活性，从而早期放大 内体，破坏神经营养信号的内体运输，并导致 BFCN 萎缩 3) 因此，降低这些 APP 产品的含量是预防或减轻影响的合理方法。 最近已证明 AD-DS 中增加的 APP 基因剂量（包括对内体的影响）是安全的。 事实上，FDA 已批准 ASO 用于脊髓性肌萎缩症动机试验。 ASOs 在其他中枢神经系统疾病中的作用在初步研究中，我们表明脑室内（ICV）注射 ASOs。 靶向小鼠和人类 APP 的 ASO（即 mAPP-ASO 和 hAPP-ASO）可减少 APP mRNA 和蛋白质 我们将使用 AD-DS 和 AD/脑淀粉样变性小鼠模型来测试治疗假设。 APP-ASOs 将选择性地降低 APP mRNA 及其产物的水平，以预防和/或减轻 神经退行性变的机制假设是 APP-ASO 将使内体结构正常化。 功能、神经营养素信号传导和运输，并使用定义的 GO/NOGO 标准改善认知。 作为指南，我们将追求以下具体目标： 1. 在体外研究新设计的 APP-ASO 的功效和 使用现有的 mAPP-ASO 作为基准，将设计额外的 mAPP-ASO 增加靶向 APP mRNA 及其产物并使内体大小正常化的效力 2. 建立。 APP-ASO 最佳剂量和剂量间隔基于经验定义的体内药代动力学 (PK) 和 我们将定义有效、无毒的剂量和治疗间隔。 将 mAPP-ASO 和 hAPP-ASO 推进目标 3 中的体内研究。在 Dp16 模型中，我们将目标 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%。 研究体内 APP-ASO 在改善神经变性和使内体正常化方面的功效 为了检验治疗假设，我们将询问是否在 Dp16 变性之前给予 APP-ASO。 小鼠和 41 系小鼠中的斑块沉积会阻止这些变化 接下来，我们将询问 Dp16 是否发生变性。 小鼠可以通过 APP-ASO 治疗来逆转，该机制假设将由是否告知。 APP-ASO 变性的减少与内体表型的正常化相关。