Applying human in vitro models to understand the link between trauma and tau pathology

应用人体体外模型来了解创伤与 tau 病理学之间的联系

基本信息

批准号：
10786930
负责人：
John D Finan
金额：
$ 45.7万
依托单位：
UNIVERSITY OF ILLINOIS AT CHICAGO
依托单位国家：
美国
项目类别：
财政年份：
2023
资助国家：
美国
起止时间：
2023-09-15 至 2025-08-31
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10786930
关键词：
3-Dimensional Adherent Culture Admission activity Agonist Alzheimer&apos s Disease Alzheimer&apos s disease related dementia Alzheimer&apos s disease risk Animal Model Astrocytes Biological Assay Blood Blood Vessels Brain Brain Injuries Calcium Calcium Channel Cell Culture Techniques Cell Death Cell Line Cells Chemicals Coculture Techniques Culture Media Cytoplasm Cytosol Disease Electrophysiology (science)Endothelial Cells Environmental Risk Factor Event Evolution Genes Glial Fibrillary Acidic Protein Goals Human Human Genome Incidence Inflammatory Interruption Investigation Label Lactate Dehydrogenase Light Link Measures Mechanics Medicine Modeling Neurons Organoids Outcome Pathology Patients Pattern Persons Phenotype Piezo 1 ion channel Play Process Prognosis Protein Secretion Recording of previous events Role Signal Transduction Source Stains Stretching TBI Patients Tauopathies Testing Time Trauma Traumatic Brain Injury Work brain cell cadherin 5 cell injury cell type cytokine empowerment experimental study improved in vitro Model induced pluripotent stem cell insight knock-down microscopic imaging millimeter monolayer neurofilament new therapeutic target personalized medicine prevent response scale up screening small hairpin RNA stem cells tau Proteins tau-1 therapeutic target

项目摘要

Traumatic brain injury (TBI) is the most important environmental risk factor for Alzheimer’s disease and Alzheimer’s disease related dementias (AD/ADRD). The TBI event may occur years before the emergence of AD/ADRD so there is time to apply treatments. Unfortunately, no appropriate treatments exist because the connection between TBI and AD/ADRD is poorly understood. Changes in tau proteins play an important role in AD/ADRD. Calcium overload drives changes in tau. Calcium overload is also a consequence of TBI. This proposal hypothesizes that TBI causes calcium overload that leads to tau changes and this sequence helps explain why TBI increases the risk of AD/ADRD. Piezo1 is a calcium channel that opens when cells deform. Therefore, it could be opened by trauma. This proposal will test this hypothesis in cortical astrocytes, cortical neurons, and endothelial cells. These cells will be generated from human induced pluripotent stem cells. The first Aim will measure how vulnerable each cell type is to trauma. The cells will be deformed in the same way they are during a TBI event and resulting cell death and cell damage will be measured. Calcium overload and inflammatory signaling will also be quantified. In patient brains, tau changes accumulate around blood vessels after TBI but it is not clear if this pattern reflects the toxic influence of blood or the endothelial cells that line blood vessels. Therefore, the influence of endothelial cells on neighboring astrocytes and neurons will be measured with experiments that either mix cells in culture or transfer cell culture media between cell cultures. Experiments with trauma-sensitive outcomes will be repeated after Piezo1 has been eliminated from the cells to determine if Piezo1 is required for a trauma response. In addition, the same outcomes will be measured in experiments that activate Piezo1 chemically without trauma. The second Aim will employ brain organoids. These are clusters of brain cells that are approximately round and about 1 millimeter wide. They contain cortical neurons and astrocytes and, in some cases, endothelial cells will be added to them. These organoids can reproduce the calcium overload-dependent tau changes that are hypothesized to drive disease in post-TBI AD/ADRD. They will be mechanically deformed in the same way they would be deformed during a TBI event. Resulting cell death and cell damage will be quantified. Secretion of proteins known to indicate brain damage and changes in spontaneous electrical activity will also be measured. In addition, total tau protein and phosphorylated tau protein will be quantified after trauma. Microscopic imaging will determine if tau changes accumulate around endothelial cells when they are present. As before, experiments that show sensitivity to trauma will be repeated after Piezo1 has been eliminated from the cells. Then, they will be repeated when Piezo1 has been activated chemically without trauma. In combination, these experiments will reproduce the progression from mechanical trauma to tau changes that drive AD/ADRD and reveal the role of Piezo1 in that process. These results will be an important step toward treating these patients to interrupt this progression.

创伤性脑损伤（TBI）是阿尔茨海默病和阿尔茨海默病最重要的环境危险因素阿尔茨海默病相关痴呆 (AD/ADRD) 事件可能发生在阿尔茨海默病出现之前数年。 AD/ADRD 因此有时间进行治疗，不幸的是，不存在适当的治疗方法，因为 TBI 与 AD/ADRD 之间的联系尚不清楚。tau 蛋白的变化在其中发挥着重要作用。 AD/ADRD。钙超载也会导致 tau 的变化。这也是 TBI 的结果。提案要求 TBI 导致钙超载，从而导致 tau 蛋白变化，这一序列有助于解释为什么 TBI 会增加 AD/ADRD 的风险。 Piezo1 是细胞变形时打开的钙通道。因此，它可以通过创伤打开，该提案将在皮质星形胶质细胞中测试这一假设。这些细胞将由人类诱导多能干细胞产生。第一个目标将测量每种细胞类型对创伤的脆弱程度。细胞会以相同的方式变形。他们正处于 TBI 事件期间，将测量由此产生的细胞死亡和细胞损伤。患者大脑中的炎症信号传导也将被量化，tau 蛋白的变化会在血管周围积累。 TBI 后，但尚不清楚这种模式是否反映了血液或内皮细胞的毒性影响因此，内皮细胞对邻近星形胶质细胞和神经元的影响将是。通过混合培养物中的细胞或在细胞培养物之间转移细胞培养基的实验来测量。 Piezo1 从细胞中消除后，将重复进行创伤诱发结果的实验以确定创伤反应是否需要 Piezo1 此外，还将测量相同的结果。在没有创伤的情况下化学激活 Piezo1 的实验将使用大脑类器官。这些是大约圆形、大约 1 毫米宽的脑细胞簇。皮质神经元和星形胶质细胞，在某些情况下，内皮细胞将被添加到这些类器官中。可以重现钙超载依赖性 tau 蛋白变化，这些变化在 TBI 后被重新捕获以驱动疾病 AD/ADRD。它们会发生机械变形，就像在 TBI 事件中发生变形一样。由此产生的细胞死亡和细胞损伤将被量化，已知表明脑损伤的蛋白质的分泌。此外，还将测量总 tau 蛋白和自发电活动的变化。创伤后，磷酸化 tau 蛋白将被定量，显微成像将确定 tau 蛋白是否发生变化。当内皮细胞存在时，它们会聚集在内皮细胞周围。与之前一样，实验显示了对内皮细胞的敏感性。当 Piezo1 从细胞中消除后，创伤将再次发生。 Piezo1 已被化学激活而没有创伤，这些实验将重现。从机械创伤到驱动 AD/ADRD 的 tau 蛋白进展变化，并揭示了 Piezo1 在其中的作用这些结果将是治疗这些患者以阻止这一进展的重要一步。