iPSC Modeling of AD Using Progerin

项目摘要/摘要 年龄是阿尔茨海默病(AD)的最大危险因素。然而，AD的细胞和动物模型未能 概括了人类的衰老，未能捕捉到疾病病理学的关键方面。我们的长期目标是 了解衰老在AD发病机制中的作用。因此，我们建议开发一种诱导式 基于多能干细胞(IPSC)的AD模型结合了加速衰老，目标是获得更多 强健地模拟AD的发病和进展。最近的发现表明，层蛋白A生物学中的扰动 可能与AD有关。在初步研究中，我们发现LMNA基因显著增加，这种基因 编码核膜蛋白Lamin A，并显著减少前Lamin A的ZMPSTE24 在尸检确认的AD脑组织和激光切割的AD脑内神经元中的加工酶 与年龄匹配的对照组相比。我们预测LMNA和ZMPSTE24水平的这些变化将 导致法尼化的前层蛋白A的增加，这已被证明是加速衰老的表型， 包括获得异常的核层，以及核质隔间的损害， 染色质的组织和基因表达类似于LMNA异构体孕激素的积累。我们 假设强制表达前层素A或孕激素会加速与年龄相关的变化和疾病 阿尔茨海默病患者IPSC-皮质细胞表型。首先，我们将确定层粘连蛋白A 在AD大脑和AD易感的IPSC-皮质细胞中，表达和处理受到干扰。到时候我们会的 确定强制表达孕激素是否会导致AD易感IPSC衰老相关功能障碍 皮质神经元和星形胶质细胞。最后，我们将定义和量化被迫表达的促进素对 与AD病理相关的细胞表型，包括Aβ和tau的分泌、聚集和周转 皮质细胞和3D前脑器官中。这项研究的结果将决定扰动是否会在 Lamin A生物学与AD相关，并可能参与AD的发病机制，并将建立一种 在人类AD IPSC-皮质细胞模型中包含层蛋白A相关衰老参数的新模型。这些 这些发现将为研究衰老在疾病机制中的作用开辟新的途径 并将推动AD体外模型的开发，以帮助设计和 验证潜在的治疗策略。

Project Summary/Abstract Age is the strongest risk factor for Alzheimer's disease (AD). However, cell and animal models of AD fail to recapitulate human aging and fail to capture key aspects of disease pathology. Our long-term goal is to understand how aging contributes to AD pathogenesis. Therefore, we propose to develop an induced pluripotent stem cell (iPSC)-based model of AD that incorporates accelerated aging, with the objective of more robustly modeling AD onset and progression. Recent findings indicate that perturbations in lamin A biology may contribute to AD. In preliminary studies, we have found a significant increase in LMNA, the gene that encodes the nuclear envelope protein lamin A, and a significant decrease in ZMPSTE24, a prelamin A processing enzyme, in autopsy-confirmed AD brain tissue and in laser-dissected neurons from AD brains compared to age-matched controls. We predict that these changes in LMNA and ZMPSTE24 levels would cause an increase in farnesylated prelamin A, which has been shown to drive accelerated aging phenotypes, including acquisition of an abnormal nuclear lamina, and impairments in nucleocytoplasic compartmentation, chromatin organization and gene expression similar to the accumulation of the LMNA isoform progerin. We hypothesize that forced expression of prelamin A or progerin accelerates age-associated changes and disease phenotypes in iPSC-cortical cells derived from AD patients. First, we will determine whether lamin A expression and processing are perturbed in AD brains and AD-predisposed iPSC-cortical cells. We will then determine whether forced progerin expression causes aging-related dysfunction in AD-predisposed iPSC- cortical neurons and astrocytes. Finally, we will define and quantify the effects of forced progerin expression on cell phenotypes related to AD pathology, including Aβ and tau secretion, aggregation and turnover, in iPSC-2D cortical cells and in 3D forebrain organoids. The results from this study will determine whether perturbations in lamin A biology are associated with AD, and potentially contribute to AD pathogenesis, and will establish a novel model incorporating lamin A-related aging parameters in a human AD iPSC-cortical cell model. These findings will open novel avenues for investigating the contribution of aging to the disease mechanisms underlying AD pathology and will advance the development of in vitro models of AD to aid in the design and validation of potential therapeutic strategies.