The role of gasdermins in microglial activation and neurodegeneration in ALS/FTD

Gasdermin 在 ALS/FTD 中小胶质细胞激活和神经退行性变中的作用

基本信息

批准号：
10749749
负责人：
Georgia Gunner
金额：
$ 6.91万
依托单位：
HARVARD MEDICAL SCHOOL
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：
2023-09-30 至 2025-09-29
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10749749
关键词：
Address Age Amyotrophic Lateral Sclerosis Animals Area Arginine Biology Brain C9ORF72 Cell Death Central Nervous System Cessation of life Coculture Techniques Collaborations DNA Sequence Alteration Data Development Dipeptides Disease Disease Progression Disease associated microglia Disease model Dyes Exposure to Flow Cytometry Foundations Frontotemporal Dementia Future Gene Expression Profile Genetic Transcription Genotype Gliosis Glycine Goals Health Heterogeneity Human Immune Immune response Immunology Impaired cognition In Vitro Inflammasome Inflammation Inflammatory Injections Institution Investigation Link Location Macrophage Mediating Mentors Metabolic Metabolic stress Microglia Mitochondria Modeling Motor Cortex Motor Neurons Mus Mutation Neonatal Nerve Degeneration Neurites Neurobiology Neurodegenerative Disorders Neurons Onset of illness Paralysed Pathology Patients Peripheral Population Positioning Attribute Principal Investigator Process Proline Protein Overexpression Proteins Role Severities Severity of illness Spinal Cord Stains Stress Superoxide Dismutase Techniques Testing Time Tissues Training Transgenic Organisms VDAC1 gene Viral Virus Weaning Work brain parenchyma career cell cortex cytokine experimental study frontotemporal lobar dementia amyotrophic lateral sclerosis genetic signature glial activation immune function mouse model mutant neural circuit neuroimmunology neuroinflammation neuron loss neuronal survival neuroprotection new therapeutic target overexpression programs protein TDP-43 protein expression pup response single-cell RNA sequencing skills survival outcome transcriptomics

项目摘要

7. Project Summary/Abstract The goal of this proposal is to elucidate a role for microglial gasdermin-D in the severity of neurodegeneration in models of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). Despite widespread evidence for microglial activation in several neurodegenerative diseases, the precise mechanisms governing these microglial responses are not well understood. Gasdermin-D (GSDMD) is a pore- forming protein expressed in peripheral macrophages that initiates a proinflammatory form of cell death termed pyroptosis. I have evidence that microglia highly express GSDMD in the central nervous system, and that in vitro primary microglia similarly form GSDMD pores when exposed to inflammasome triggers. Using the well- described SOD1G93A model of ALS, I found a significant increase in microglial Gsdmd transcription and activation at the protein level in the spinal cord as paralysis progresses. In a separate model of C9ORF72-associated FTD, I found Gsdmd expression increases in the brain after neuronal overexpression of a dipeptide repeat expansion (DRE) protein. While Gsdmd expression is similarly increased in both models, using a Gsdmd null animal in either disease context results in an opposite effect on animal survival where GSDMD drives protection in the ALS disease model but disease progression in the C9ORF72 model of FTD. Transcriptomic work on microglia across development and in neurodegeneration suggests microglia have differing immune functions based on their resident location in the brain, animal age, and in health versus disease. I aim to further understand the heterogeneity of microglial responses in the CNS in neurodegeneration by addressing the following questions: 1) How does Gsdmd expression drive protection in the SOD1G93A model of ALS (Aim 1) but conversely drive disease progression in a model of C9ORF72 FTD (Aim 2)? 2) How do microglial transcriptional profiles change with loss of Gsdmd expression in the spinal cord and brain in ALS and FTD disease models (Aims 1 and 2)? I hypothesize microglial GSDMD results in opposing effects on survival outcome due to disease context- dependent changes in microglial immune profiles. To test this hypothesis, I plan to use flow cytometry and single cell RNAseq which are powerful approaches to interrogating microglial function and techniques for which I will acquire new scientific skills. I also have developed strong collaborations to model FTD with AAV strategies, as well as a strong mentoring team including my mentor Dr. Isaac Chiu as well as Dr. Judy Lieberman, Dr. Beth Stevens, and Dr. Leonard Petrucelli who are experts in neuroimmunology, gasdermin biology, microglia, and neurodegeneration, respectively. Together, I am in a strong position to interrogate microglial Gsdmd activation in ALS and FTD neurodegeneration. In the process of completing the experiments in this proposal, I will receive training in a variety of immunology and neurobiology approaches that will provide a foundation for my future career as an independent principal investigator at an academic institution focused on dissecting functions for microglia within neural circuits.

7. 项目总结/摘要该提案的目的是阐明小胶质细胞gasdermin-D 在严重程度中的作用肌萎缩侧索硬化症（ALS）和额颞叶痴呆（FTD）模型中的神经退行性变。尽管有广泛的证据表明小胶质细胞激活在几种神经退行性疾病中，但精确的控制这些小胶质细胞反应的机制尚不清楚。 Gasdermin-D (GSDMD) 是一种孔形成在外周巨噬细胞中表达的蛋白质，启动促炎形式的细胞死亡，称为细胞焦亡。我有证据表明小胶质细胞在中枢神经系统中高度表达 GSDMD，并且在体外当暴露于炎症小体触发物时，初级小胶质细胞类似地形成 GSDMD 孔。使用井- 描述了 ALS 的 SOD1G93A 模型，我发现小胶质细胞 Gsdmd 转录和激活显着增加随着瘫痪的进展，脊髓中的蛋白质水平。在 C9ORF72 相关 FTD 的单独模型中，我发现二肽重复扩增的神经元过度表达后大脑中 Gsdmd 的表达增加（DRE）蛋白质。虽然 Gsdmd 表达在两种模型中都有类似的增加，但使用 Gsdmd 无效动物任何一种疾病都会对动物生存产生相反的影响，而 GSDMD 会在动物中推动保护。 ALS 疾病模型，但 FTD 的 C9ORF72 模型中疾病进展。小胶质细胞的转录组工作跨越发育和神经退行性变表明小胶质细胞具有不同的免疫功能它们在大脑中的驻留位置、动物年龄以及健康与疾病的关系。我的目的是进一步了解通过解决以下问题，研究神经退行性中枢神经系统小胶质细胞反应的异质性： 1) Gsdmd 表达式如何驱动 ALS 的 SOD1G93A 模型中的保护（目标 1），但反过来又驱动 C9ORF72 FTD 模型中的疾病进展（目标 2）？ 2）小胶质细胞转录谱如何变化 ALS 和 FTD 疾病模型中脊髓和大脑中 Gsdmd 表达缺失（目标 1 和 2）？我假设小胶质细胞 GSDMD 由于疾病背景而对生存结果产生相反的影响小胶质细胞免疫特征的依赖性变化。为了检验这个假设，我计划使用流式细胞术和单细胞 RNAseq 是研究小胶质细胞功能的强大方法和技术，我将对此进行研究获得新的科学技能。我还建立了强有力的合作关系，利用 AAV 策略对 FTD 进行建模，例如以及强大的指导团队，包括我的导师 Isaac Chiu 博士以及 Judy Lieberman 博士、Beth 博士 Stevens 和 Leonard Petrucelli 博士是神经免疫学、gasdermin 生物学、小胶质细胞和分别是神经退行性疾病。总之，我在研究小胶质细胞 Gsdmd 激活方面处于有利地位 ALS 和 FTD 神经变性。在完成本提案中的实验过程中，我将收到接受各种免疫学和神经生物学方法的培训，这将为我的未来奠定基础作为学术机构的独立首席研究员，专注于剖析以下领域的职能神经回路内的小胶质细胞。