Role of ER Stress in the Pathogenesis of Primary Open Angle Glaucoma

内质网应激在原发性开角型青光眼发病机制中的作用

基本信息

批准号：
9039612
负责人：
Gulab Zode
金额：
$ 24.86万
依托单位：
UNIVERSITY OF NORTH TEXAS HLTH SCI CTR
依托单位国家：
美国
项目类别：
财政年份：
2014
资助国家：
美国
起止时间：
2014-04-01 至 2018-03-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9039612
关键词：
Advisory Committees Apoptosis Apoptotic Aqueous Humor Autophagocytosis Autopsy Cell Death Cells Chronic Clinical Data Degradation Pathway Development Dexamethasone Diagnosis Disease Educational process of instructing Endoplasmic Reticulum Eye Failure Functional disorder GRP78 gene GRP94 Genetic Glaucoma Homeostasis Human Individual Knockout Mice Laboratories Laboratory Research Lead Learning Lysosomes Mentors Modeling Molecular Chaperones Mus Mutation Nerve Degeneration Ocular Hypertension Optic Nerve Pathogenesis Pathway interactions Patients Phase Phenotype Phenylbutyrates Phosphorylation Physiologic Intraocular Pressure Play Primary Open Angle Glaucoma Process Proteins Research Institute Resistance Retinal Ganglion Cells Risk Factors Role Sirolimus Sodium phenylbutyrate Steroids Testing Tissues Topical application Trabecular meshwork structure Training Transgenic Mice Transgenic Organisms Western Blotting abstracting career development common treatment endoplasmic reticulum stress experience genetic risk assessment improved induced pluripotent stem cell inhibitor/antagonist insight mouse model mutant myocilin novel prevent protein aggregate protein degradation protein misfolding public health relevance response sensor symposium

项目摘要

Abstract Primary open angle glaucoma (POAG), the most common form of glaucoma, is usually accompanied by elevated intraocular pressure (IOP) due to failure of the trabecular meshwork (TM) to maintain normal levels of aqueous humor outflow. We recently generated a novel transgenic murine model (Tg-MYOCY437H) that expresses mutant myocilin, a known leading genetic cause of POAG in humans and replicates human glaucoma phenotypes. Importantly, we have associated endoplasmic reticulum (ER) stress to the pathogenesis of glaucoma in Tg-MYOCY437H mice. Misfolded myocilin accumulates in the ER, induces ER stress and activates a protective unfolded protein response (UPR). Along with UPR activation, mutant myocilin also induces autophagy, a process of lysosomal degradation known to degrade protein aggregates. However, failure to eliminate myocilin aggregates possibly due to insufficient UPR and impaired autophagy, TM cells induce the ER stress-initiated apoptotic transcriptional factor, Chop, which may further worsen ER homeostasis and cause TM dysfunction/loss, elevating IOP and resulting in POAG. The current proposal will further investigate the role of chronic ER stress in the pathogenesis of myocilin as well as non-myocilin associated POAG. During the mentored phase, the proposed studies will determine whether failure to activate the protective UPR (Atf-6�-/-) exacerbates glaucoma phenotypes, whereas interference with ER stress-induced apoptosis (Chop-/-) prevents glaucoma in Tg-MYOCY437H mice. In addition, we will investigate whether ER stress is activated in port-mortem TM tissues from POAG donors. During the independent phase, we will examine whether induction of ER stress in the TM is associated with elevation of IOP in a mouse model of dexamethasone-induced ocular hypertension. In addition, we will examine the role of autophagy in degradation of myocilin aggregates and will determine whether inducing autophagy by rapamycin will rescue the glaucoma of Tg-MYOCY437H mice. Specifically, the candidate will learn and generate new models of ER stress using Atf6� and Chop knockout mice, generate induced pluripotent stem cells (iPSCs)-derived trabecular meshwork- like cells from POAG patients, and characterize a dexamethasone-induced ocular hypertension mouse model in the laboratory of Dr. Val Sheffield. Additionally, during the mentored phase, the candidate will continue his professional and scientific career development through continual guidance from the advisory committee. He will attend scientific conferences, and collaborate with ER stress expert, Dr. Thomas Rutkowski and glaucoma clinical expert, Dr. Lee Alward. He will also acquire teaching experience. This project will facilitate continued technical, intellectual, and professional training of the candidate, and assist the candidate in the establishment of an independent research laboratory at an academic research institute.

抽象的初级开角青光眼（POAG）是青光眼最常见的形式，通常伴随由于小梁网（TM）失败以维持正常水平，因此眼内压（IOP）升高水性幽默出口。我们最近生成了一种新型的转基因鼠模型（TG-Myocy437h），该模型是表达突变体肌动蛋白，这是人类POAG的已知主要遗传原因，并复制人类青光眼表型。重要的是，我们将内质网（er）应力与 Tg-肌细胞437H小鼠青光眼的发病机理。肌蛋白折叠率折叠在ER中积聚，引起ER 压力并激活受保护的展开的蛋白质反应（UPR）。随着UPR激活，突变体肌动蛋白还影响自噬，这是一种已知降解蛋白质聚集体的溶酶体降解过程。然而，无法消除可能是由于UPR不足和自噬受损而导致的肌动蛋白聚集体诱导ER应力引起的凋亡转录因子CHOP，这可能会进一步稳定稳态并引起TM功能障碍/损失，升高IOP并导致POAG。当前的提议将进一步研究慢性ER应激在肌动蛋白以及非肌依肽蛋白的发病机理中的作用 Poag。在修订阶段，提出的研究将确定是否未能激活保护性UPR（ATF-6。细胞凋亡（CHOP - / - ）可防止TG-Myocy437h小鼠中的青光眼。此外，我们将调查是否 POAG供体的港口验尸TM组织激活了应力。在独立阶段，我们将检查TM中的ER应力是否与IOP升高有关地塞米松诱导的眼部高血压。此外，我们将研究自噬在降解中的作用肌动蛋白骨料的骨料，并将确定雷帕霉素诱导的自噬是否会挽救青光眼 TG-Myocy437h小鼠的。具体而言，候选人将学习并生成新的ER压力模型 ATF6。和CHOP基因敲除小鼠，产生诱导的多能干细胞（IPSC）衍生的小梁网络像POAG患者的细胞，并表征地塞米松诱导的眼部高血压小鼠模型在Val Sheffield博士的实验室中。此外，在修补阶段，候选人将继续他的通过咨询委员会的持续指导，专业和科学的职业发展。他将参加科学会议，并与ER压力专家Thomas Rutkowski和青光眼合作临床专家李·阿尔沃德（Lee Alward）博士。他还将获得教学经验。这个项目将有助于继续候选人的技术，智力和专业培训，并协助候选人建立一家学术研究所的独立研究实验室。