Glysocaminoglycan Modifications as Regulators of Alzheimer's Disease-Related Pathologies

糖胺聚糖修饰作为阿尔茨海默病相关病理的调节剂

• 批准号: 10461886
• 负责人: SCOTT B SELLECK
• 金额: $ 19.77万
• 依托单位: PENNSYLVANIA STATE UNIVERSITY, THE
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-08-15 至 2024-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10461886
• 关键词: Adenosine; Adult; Affect; Alzheimer' s Disease; Alzheimer' s disease model; Area; Autophagocytosis; Autophagosome; Biological Markers; Biological Process; CRISPR/Cas technology; Cell physiology; Cell surface; Cells; Chondroitin Sulfates; Clustered Regularly Interspaced Short Palindromic Repeats; Cytoprotection; Development; Disease; Drosophila genus; Endocytosis; Endosomes; Environment; Enzymes; Excision; Extracellular Matrix; Genes; Goals; Heparan Sulfate Biosynthesis; Heparan Sulfate Proteoglycan; Heparitin Sulfate; Human; Human Cell Line; Induced pluripotent stem cell derived neurons; Intervention; Laboratories; Length; Lentivirus; Lentivirus Vector; Longevity; Lysosomes; Medical; Membrane; Mitochondria; Modeling; Modification; Molecular; Morphology; Mutation; Nerve Degeneration; Neurodegenerative Disorders; Neurons; Organelles; Oxidative Stress; Pathogenesis; Pathology; Patients; Pattern; Phenotype; Play; Process; Proteins; Proteoglycan; Proteome; Regulation; Research Priority; Resistance; Role; Structure; Sulfate; Susceptibility Gene; System; Technology; Work; age related; base; clinically relevant; experimental study; familial Alzheimer disease; fluorophore; glycosylation; human stem cells; human tissue; in vivo; induced pluripotent stem cell; knock-down; macromolecule; mutant; neuron loss; presenilin; presenilin-1; programs; protein aggregation; protein distribution; protein folding; protein function; sabbatical; sensor; therapeutic target; trafficking

Project Summary/Abstract As described by the High Priority Research Topics for this RFA, there is compelling evidence that glycosylation plays “critical roles in the early pathogenesis and progression of AD” yet the “potential of these molecules to serve as biomarkers and targets of disease intervention remains largely unexplored”. Specific areas of program relevance included the “role of extracellular matrix and proteoglycans in … accumulation of AD-related pathologies”. These areas are topics my laboratory has recently explored and my group has been involved in establishing the biological functions of heparan sulfate modified proteins over the last 20 years. In recent work we have shown that heparan sulfate proteoglycans regulate membrane trafficking, including autophagy, endocytosis and mitochondrial surveillance(1), processes central to neurodegenerative pathology. We have shown that modest changes in heparan sulfate structure, such as sulfation state or chain length, can increase catabolic membrane trafficking, including delivery of autophagosomes to the lysosome. These findings suggest that changing heparan sulfate structure could counteract the cellular processes that are compromised in AD and related pathologies. This hypothesis is supported by our demonstration that partial reductions in specific heparan sulfate modifying enzyme encoding genes can suppress cell loss in three distinct Drosophila models of neurodegenerative diseases(2) including AD. It is important to point out that the level of these changes do not disrupt developmental patterning but actually confers increased lifespan and resistance to oxidative stress. Using a panel of CRISPR-generated mutant human cell lines affecting heparan sulfate biosynthesis we have shown that the regulation of membrane trafficking by these molecules is conserved in human cells. We now wish to extend these observations into medically relevant models of AD to determine if heparan sulfate biosynthesis is a viable therapeutic target for AD and related pathologies. These studies employ both iPSC-derived neurons bearing mutations in known AD susceptibility genes (presenilin and APP), and a Drosophila model of age-dependent neurodegeneration, where conditional knockdown of presenilin function is achieved in adult neurons. In both of these systems we propose to determine if changes in heparan sulfate biosynthesis achieved by targeted knockdown of key biosynthetic enzyme encoding genes can achieve rescue of cellular phenotypes, and reverse the alterations in autophagy, mitophagy, and membrane trafficking that have been observed in human tissues as well as iPSC-derived neurons from patients.

项目概要/摘要 正如本 RFA 的高优先级研究主题所述，有令人信服的证据 糖基化在“AD 的早期发病机制和进展中发挥着关键作用”，但 “这些分子作为生物标志物和疾病干预目标的潜力仍然存在 很大程度上尚未探索”。计划相关的具体领域包括“细胞外的作用 AD 相关病理积累中的基质和蛋白聚糖”。这些领域是 我的实验室最近探索的主题，我的小组参与了建立 过去 20 年硫酸乙酰肝素修饰蛋白的生物学功能。在最近的工作中 我们已经证明硫酸乙酰肝素蛋白聚糖调节膜运输，包括 自噬、内吞作用和线粒体监视(1)，这些过程的核心 神经退行性病理学。我们已经证明硫酸乙酰肝素的适度变化 结构，例如硫酸化状态或链长，可以增加分解代谢膜运输， 包括将自噬体递送至溶酶体。这些发现表明改变 硫酸乙酰肝素结构可以抵消 AD 中受损的细胞过程 和相关的病理。这个假设得到了我们的证明的支持，即部分 特定硫酸乙酰肝素修饰酶编码基因的减少可以抑制细胞损失 包括 AD 在内的三种不同的果蝇神经退行性疾病模型 (2)。这是 需要指出的是，这些变化的程度不会破坏发育模式 但实际上可以延长寿命并增强对氧化应激的抵抗力。使用面板 CRISPR 生成的突变人类细胞系影响硫酸乙酰肝素生物合成 研究表明，这些分子对膜运输的调节在人类中是保守的 细胞。我们现在希望将这些观察结果扩展到 AD 的医学相关模型中 确定硫酸乙酰肝素生物合成是否是 AD 及相关疾病的可行治疗靶点 病理学。这些研究使用了已知 AD 中携带突变的 iPSC 衍生神经元 易感基因（早老素和 APP）和年龄依赖性果蝇模型 神经退行性疾病，其中在成人中实现了早老素功能的条件性敲除 神经元。在这两个系统中，我们建议确定硫酸乙酰肝素是否发生变化 通过靶向敲除关键生物合成酶编码基因实现生物合成 实现细胞表型的拯救，逆转自噬、线粒体自噬和线粒体自噬的改变 在人体组织以及 iPSC 衍生的组织中观察到的膜运输 来自患者的神经元。