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.

我们的目标是在DS(21三体)(AD-DS)中预防阿尔茨海默病(AD)。使用反义寡核苷酸 (ASOS)，我们将选择性地针对AD-DS(Dp16)小鼠模型中的淀粉样前体蛋白(APP)的RNA。 和AD/脑淀粉样变性(41行)。治疗的前提是：1)增加APP基因剂量 对于AD-DS来说是必要的。正如在AD-DS模型中复制的那样，使APP剂量正常化消除了：a)年龄相关 蓝斑和基底前脑复合体的神经退行性变，b)Tau过度磷酸化，c) 早期内小体的增大；2)表明APP基因剂量增加，全长增加的机制 APP(fl-APP)、其99个残基C-末端片段(C99)和Aβ42分别增加了Rab5的活性，从而早期放大 内体，扰乱内体对神经营养信号的转运，并导致BFCNs萎缩；3) 因此，降低这些APP产品的水平是预防或减轻 增加AD-DS的APP基因剂量，包括对内小体的影响。ASO最近被证明是安全的 并有效治疗中枢神经系统疾病。事实上，FDA批准ASO治疗脊髓性肌萎缩症是一项激励试验 ASOS在其他中枢神经系统疾病中的作用。在初步研究中，我们发现脑室(Icv)注射 靶向小鼠和人类APP的ASO(即Mapp-ASOS和Happ-ASOS)减少了APP的mRNA和蛋白 级别。使用AD-DS和AD/脑淀粉样变性的小鼠模型，我们将检验治疗假说 APP-ASOS将选择性地降低APP mRNA及其产品的水平，以防止和/或减少 神经退行性变。机制假说是APP-ASOS将使内体结构正常化和 功能，神经营养因子信号和运输，并改善认知。使用定义的GO/NOGO标准作为 作为指南，我们将追求以下具体目标：1.研究新设计的APP-ASO的体外疗效和 靶标特异性。使用现有的Mapp-ASO作为基准，其他Mapp-ASO将被设计为 增加针对APP mRNA及其产物的效力，并使内体大小正常化。2.确立 最佳APP-ASO剂量和剂量间隔基于经验定义的体内药代动力学(PK)和 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AIM 3中，MAPP-ASOS和HAPP-ASOS在体内研究中的进展。在Dp16模型中，我们将针对 ~33%的Mapp RNA减少，即2N值；在第41行小鼠中，我们的目标是减少50%。目标3.至 APP-ASO改善神经退行性变和内体正常化的体内实验研究 表型。为了检验治疗假说，我们将询问在Dp16变性之前是否给予APP-ASO 小鼠和第41行小鼠的斑块沉积可以阻止这些变化。接下来，我们将询问Dp16中是否存在退化 APP-ASO治疗可以逆转小鼠的病情。机械假说将由以下因素决定： APP-ASO退变的减少与内体表型的正常化相关。