Identifying and leveraging strategies of inherently resilient retinal neurons to treat degeneration

识别和利用固有弹性视网膜神经元的策略来治疗退化

基本信息

批准号：
10446816
负责人：
Philip Raymond Williams
金额：
$ 39.01万
依托单位：
WASHINGTON UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2022
资助国家：
美国
起止时间：
2022-06-01 至 2027-03-31
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10446816
关键词：
Affect Animal Model Axon Axotomy Biological Assay Biosensor Blindness Brain Caliber Cell Death Cell Energetics Cell Survival Cells Cessation of life Clinical Coping Skills Data Degenerative Disorder Development Diabetic Neuropathies Diabetic Retinopathy Disease Disease Progression Endoplasmic Reticulum Eye Fingerprint Foundations Gene Expression Genes Glaucoma Goals Heterogeneity Homeostasis Human Image Individual Intervention Maintenance Measurement Measures Metabolic Metabolism Mitochondria Modeling Mus Nature Nerve Crush Nerve Degeneration Neurons Optic Nerve Optic Nerve Glioma Optic Nerve Injuries Optic Neuritis Outcome Pathway interactions Patients Pharmacology Phenotype Physiologic Intraocular Pressure Population Population Heterogeneity Production Property Proteins Regulation Repression Research Resolution Rest Retina Retinal Ganglion Cells Role Source Testing Therapeutic Agents Time Translating Trauma Vision age related neurodegeneration axon injury cell type experimental study human disease human model imaging approach improved in vivo in vivo imaging knock-down legally blind neuron loss novel novel strategies novel therapeutics optic nerve disorder overexpression preservation prevent resilience response retinal ganglion cell degeneration retinal neuron sample collection sight restoration survival outcome trait treatment strategy two-photon

项目摘要

ABSTRACT Retinal ganglion cells (RGCs) are the sole connection between the eye and the brain. They are particularly susceptible to degeneration, and their damage and death leads to vision loss in conditions like glaucoma, diabetic retinopathy, optic nerve glioma, and optic neuritis. Most treatments for these diseases are not focused on specifically rescuing RGCs, but on relieving apparent drivers of disease progression. For example, current glaucoma treatments focus on reducing elevated intraocular pressure (IOP), but are not effective in the majority of patients. Further, many glaucoma patients also have RGC degeneration without IOP elevations. Thus, new treatments to preserve RGCs in degenerative diseases represent an important unmet clinical need. Although RGC cell death leads to vision loss, RGC death in degenerative conditions is incomplete even in severely affected patients and robust animal models. Understanding how some RGCs natively persist in degenerative conditions can inform the development of new treatment strategies. To identify native coping strategies, we will directly observe cellular traits of individual RGCs prior to and during the course of degeneration, focusing on cellular homeostasis. We have established longitudinal, in vivo, 2-photon imaging of genetically encoded biosensors in RGCs to directly observe energetic and Ca2+ homeostasis at single RGC resolution repeatedly over a protracted period of time. This approach allows for measurements that would normally require either end point sample collection, pooling of RGCs from multiple retinae, or both; limitations that obscure population heterogeneity and individual cell dynamics. We will characterize baseline heterogeneity of energetic and Ca2+ homeostasis, along with dynamics following axon injury and directly relate these measurements with RGC survival or death. Mechanisms of homeostasis are highly relevant to a range of degenerative diseases but have yet to be thoroughly investigated in models of RGC degeneration. Our preliminary data indicate that mouse RGCs that natively survive optic nerve crush have salient features of energetic and Ca2+ homeostasis that can be distinguished from the RGC population as a whole prior to induction of degeneration. These results strongly suggest that homeostatic set-points influence RGC survival outcomes in a severe degeneration model. Further, we will conduct experiments to preserve RGCs in optic nerve crush models by manipulating these pathways to mimic the properties of resilient RGCs using both gene overexpression or repression interventions. Doing so we can validate which of our observations are correlative or causative. The goals of our proposal are thus to: more thoroughly define the homeostatic fingerprint of well surviving RGCs; determine how axotomy induced degeneration impinges on homeostasis of well-surviving versus poorly-surviving RGCs; and translate this information into interventions that preserve RGCs that would otherwise degenerate. Taken together our experiments will identify and validate new approaches towards protection of RGCs.

抽象的视网膜神经节细胞（RGC）是眼睛和大脑之间的唯一联系。他们尤其是容易受到堕落的影响，其损害和死亡会导致青光眼，糖尿病等状况的视力丧失视网膜病变，视神经神经胶质瘤和视神经炎。这些疾病的大多数疗法都不关注专门营救RGC，但要缓解明显的疾病进展驱动因素。例如，当前青光眼治疗的重点是降低升高的眼内压（IOP），但在大多数方面无效患者。此外，许多青光眼患者也有RGC变性，而没有IOP升高。因此，新的保存退行性疾病中RGC的治疗方法代表了重要的未满足的临床需求。虽然 RGC细胞死亡导致视力丧失，即使在严重的影响患者和健壮的动物模型。了解某些RGC在退化中如何持续存在条件可以告知新的治疗策略的发展。为了确定本地应对策略，我们将直接观察到变性之前和期间单个RGC的细胞性状，重点细胞稳态。我们已经建立了基因编码的纵向，体内的2光子成像 RGC中的生物传感器直接在单个RGC分辨率下直接观察到能量和Ca2+稳态在旷日持久的时间段内。这种方法允许进行通常需要任一端的测量点样品收集，来自多个视网膜的RGC或两者兼而有之；掩盖人口的局限性异质性和单个细胞动力学。我们将表征能量和CA2+的基线异质性稳态，以及轴突损伤后的动态，并将这些测量与RGC直接相关联生存或死亡。稳态的机制与一系列退化性疾病高度相关，但具有然而，要在RGC变性模型中进行彻底研究。我们的初步数据表明鼠标本地生存的视神经挤压的RGC具有能量和Ca2+稳态的显着特征在诱导退化之前，请先将RGC种群与RGC种群区分开。这些结果强烈表明体内平衡的设定点会影响严重的变性模型中的RGC存活结果。更远，我们将通过操纵这些途径到使用基因过表达或抑制干预措施模仿弹性RGC的特性。这样做可以验证我们的哪些观察结果是相关或因果关系的。因此，我们提案的目标是：更多彻底定义了幸存的RGC的体内平衡指纹；确定轴切开术是如何诱导的堕落会影响良好的稳态，而不利的RGC也会影响脱颖而出；并翻译这个信息中的干预措施，可以保留否则会退化的RGC。总结我们实验将识别并验证保护RGC的新方法。