Investigating the contributions of astrocyte gap junctions to ALS disease progression

研究星形胶质细胞间隙连接对 ALS 疾病进展的贡献

基本信息

批准号：
8952144
负责人：
NICHOLAS J MARAGAKIS
金额：
$ 24.3万
依托单位：
JOHNS HOPKINS UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2015
资助国家：
美国
起止时间：
2015-06-01 至 2017-05-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8952144
关键词：
Acceleration Address Amyotrophic Lateral Sclerosis Anatomy Animal Model Astrocytes Biochemical Pathway Biological Assay Biology Blood Vessels Body Regions Buffers Calcium Calcium Signaling Cell Communication Cells Cessation of life Coculture Techniques Connexin 43 Connexins Coupled Coupling Data Development Diagnosis Disease Disease Progression Elements Environment Event Eye Functional disorder Future Gap Junctions Genetic Glial Fibrillary Acidic Protein Homidium Bromide Human Image In Situ In Vitro Injection of therapeutic agent Intervention Investigation Knock-out Learning Mediating Modeling Motor Neurons Mus Mutation Neuraxis Neurons Patients Physiology Play Proteins Regulation Rodent Rodent Model Role Signal Transduction Spinal Cord Subfamily lentivirinae Symptoms Synapses System Testing Therapeutic Time Toxic effect Transgenic Organisms Translating Up-Regulation base design extracellular human stem cells human subject human tissue in vitro Model in vivo in vivo Model induced pluripotent stem cell intercellular communication knock-down mutant neuron loss neuroprotection neurotoxicity public health relevance release factor small hairpin RNA tool

项目摘要

DESCRIPTION (provided by applicant): Understanding why disease progression in the majority of patients with Amyotrophic Lateral Sclerosis (ALS) occurs in contiguous anatomic regions over time is one of the fundamental limitations to designing disease modifying therapies that can be utilized after a diagnosis. Studies from chimeric mice with mosaic expression of wildtype (WT) and mutant SOD1 astrocytes surrounding motor neurons suggest that astrocytes play a role in disease propagation after onset. However, astrocyte dysfunction is not an observation merely limited to transgenic ALS rodent models but, importantly, has been one of the most consistent observations in humans with ALS when examined in situ as well as using human cells in vitro. Astrocytes form a highly coupled intercellular network in the central nervous system (CNS) through gap junctions (GJs) and hemichannels composed of 6 connexin subunits arranged around a central pore. Connexins in astrocytes have key roles: homeostatic buffering, synchronization of astrocyte networks, metabolic support for neurons, and regulation of vascular physiology. They can also propagate Ca2+ waves and modulate synaptic events or release gliotransmitters through hemichannels. Cx43 is the predominant connexin in astrocytes and is expressed ubiquitously in the CNS. Our preliminary data show that Cx43 is upregulated in ALS models as well as in human spinal cord and cortex in patients with ALS. Yet the functional significance of this Cx43 upregulation has not been studied in ALS. Because Cx43 has a role in astrocyte connectivity and cell-cell signaling, we hypothesize that astrocyte Cx43 upregulation in ALS may contribute to neuronal loss as well as contiguous anatomical disease spread in ALS. This proposal will address the functional significance of these changes in vitro using rodent-derived astrocytes and, importantly, human iPSC-derived astrocytes from ALS patients. The specific influences of Cx43 upregulation in ALS astrocytes on wildtype motor neurons loss will also be investigated in vitro. Finally, we will utilize a variety of genetic strategies as well as focal knockdown of Cx43 in ALS animal models, to address whether reductions in Cx43 can limit disease spread. These studies will occur with an eye towards the potential for translating what is learned about Cx43-mediated astrocytic influences on disease progression and spread to the development of potential pharmacological strategies for intervention after an ALS diagnosis.

描述（由申请人提供）：了解为什么大多数肌萎缩侧索硬化症 (ALS) 患者的疾病进展会随着时间的推移发生在连续的解剖区域，是设计诊断后可使用的疾病修饰疗法的基本限制之一。来自运动神经元周围野生型（WT）和突变型 SOD1 星形胶质细胞嵌合表达的嵌合小鼠表明，星形胶质细胞在疾病发病后的传播中发挥作用，然而，星形胶质细胞功能障碍并不是一种原因。观察仅限于转基因 ALS 啮齿动物模型，但重要的是，在原位检查以及使用体外人类细胞进行的 ALS 人类研究中，星形胶质细胞在中枢神经系统中形成了高度耦合的细胞间网络，这是最一致的观察结果之一。 CNS）通过间隙连接（GJ）和由 6 个连接蛋白亚基组成的半通道，星形胶质细胞中的连接蛋白具有关键作用：稳态缓冲、星形胶质细胞网络的同步、它们还可以传播 Ca2+ 波并通过半通道调节突触事件或释放胶质递质。Cx43 是星形胶质细胞中的主要连接蛋白，并且在 CNS 中普遍表达。在 ALS 模型以及 ALS 患者的人类脊髓和皮质中，这种 Cx43 上调的功能意义尚未得到研究。由于 Cx43 在星形胶质细胞连接和细胞间信号传导中发挥作用，因此我们发现 ALS 中星形胶质细胞 Cx43 的上调可能会导致 ALS 中的神经元损失以及连续的解剖疾病扩散。该提案将解决这些变化的功能意义。在体外使用啮齿动物衍生的星形胶质细胞，以及重要的是来自 ALS 患者的人 iPSC 衍生的星形胶质细胞，研究了 ALS 星形胶质细胞中 Cx43 上调对野生型运动神经元损失的具体影响。最后，我们将利用各种遗传策略以及 ALS 动物模型中 Cx43 的局部敲除，来探讨 Cx43 的减少是否可以限制疾病传播。将 Cx43 介导的星形细胞对疾病进展和传播影响的知识转化为 ALS 诊断后干预的潜在药理学策略的开发。