DNA Nanostructures as siRNA Delivery Vehicles for Alzheimer's Therapy

项目摘要/摘要 阿尔茨海默病(AD)是最常见的与年龄相关的神经退行性疾病，其特征是 认知能力的逐渐恶化。目前治疗AD的有效方法是对症药物 旨在改善认知和行为症状，而不改变疾病的潜在病程或 延缓疾病的发展。因此，有必要对AD采取疾病修正治疗策略，使其 可阻断或修饰导致神经变性的分子病理步骤。RNA干扰是其中之一 这种策略一直被积极地用于选择性敲除AD靶基因，但通常使用 病毒载体存在准备和安全方面的问题。 我们提出了一种新的DNA纳米技术方法来克服这些问题。DNA纳米技术提供了 对建筑物形状和结构的近原子控制，消除了药物载体大小的异质性。脱氧核糖核酸 可以用额外的化学基团功能化，从而允许药物分子的可控附着和 保护药物不被生物降解。由于DNA是一种生物材料，DNA纳米结构引发了 当用于药物输送时，最小的免疫反应是无毒的、生物相容的和可生物降解的。 此外，DNA纳米结构可以进入细胞，而不需要转染剂。我们的方法将使用 DNA多面体作为基于RNA干扰的AD治疗的模型结构。具体来说，我们会：(1) 开发可控结合小干扰RNA的DNA多角体并掺入2‘-O- 甲基链，以增强生理环境中的生物稳定性，以及(2)建立DNA的活性 基于纳米结构的药物在人诱导多能干细胞(IPSC)来源的AD模型细胞系中的传递。 我们的提案汇集了一个由不同的化学研究人员组成的跨学科团队， 生物学、神经紊乱为RNAi治疗AD提供了一种新的方法。建议数 该战略具有许多优势，包括(I)精确的药物加载和定量，(I)生物相容性 和生物降解性，(Iii)低剂量高效，和(Iv)增强的生物稳定性，以承受 生理条件和复杂的生物体液。我们预计，我们的方法将提供可靠的证据 通过DNA纳米结构提供可行的siRNA的概念，在AD的临床治疗中具有巨大的潜力。

Project Summary/Abstract Alzheimer’s disease (AD) is the most common age-related neurodegenerative disorder, characterized by progressive deterioration of cognitive capacity. Currently available treatments for AD are symptomatic agents that aim to improve cognitive and behavioral symptoms without altering the underlying course of the disease or slowing disease progression. Thus, there is a necessity for disease-modifying treatment strategies for AD that can block or modify the molecular pathological steps leading to neurodegeneration. RNA interference is one such strategy that has been actively pursued for selective knockdown of AD target genes, but typically used viral vectors have preparation and safety concerns. We propose a new DNA nanotechnology approach to overcome these issues. DNA nanotechnology offers near-atomic control over building shapes and structures, eliminating heterogeneity in size of drug carriers. DNA can be functionalized with additional chemical groups that allow controllable attachment of drug molecules and protect the drug against biological degradation. Since DNA is a biological material, DNA nanostructures elicit minimal immune response when used in drug delivery, are non-toxic, biocompatible and biodegradable. Further, DNA nanostructures can enter cells without the need for a transfection agent. Our approach will use DNA polyhedra as model structures for RNA interference based treatment of AD. Specifically, we will: (1) develop DNA polyhedra with controllable attachment of small interfering RNAs (siRNAs) and incorporate 2'-O- methyl strands to enhance biostability in physiological environments, and (2) establish viability of DNA nanostructure-based drug delivery in human induced pluripotent stem cell (iPSC) derived AD model cell lines. Our proposal brings together an interdisciplinary team comprising a diverse group of researchers in chemistry, biology, and neurological disorders to provide a novel approach for RNAi treatment of AD. The proposed strategy has a number of advantages including (i) precise drug loading and quantification, (i) biocompatibility and biodegradability, (iii) low dosage with high efficacy, and (iv) enhanced biostability to withstand physiological conditions and complex biofluids. We anticipate that our approach will provide a robust proof of concept for viable siRNA delivery by DNA nanostructures with great future potential for clinical treatment of AD.