Crosstalk between chronic ER stress and mitophagy for the treatment of POAG

慢性 ER 应激与线粒体自噬治疗 POAG 之间的串扰

基本信息

批准号：
10445174
负责人：
Gulab Zode
金额：
$ 37万
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：
2016
资助国家：
美国
起止时间：
2016-03-01 至 2023-03-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10445174
关键词：
Autophagocytosis Autopsy Biological Assay Blindness Cell Death Cell model Cell physiology Cells Cessation of life Chronic Deposition Disease Endoplasmic Reticulum Enhancers Exhibits Extracellular Matrix Eye Eyedrops Fibrosis Functional disorder Funding Genetic Genus Hippocampus Glaucoma Glucocorticoids Goals Health Homeostasis Human Impairment In Vitro Link Lysosomes Membrane Metformin Mitochondria Molecular Mus Nerve Degeneration Normal tissue morphology Ocular Hypertension Organelles Pathologic Pathology Pathway interactions Pharmacology Physiologic Intraocular Pressure Play Primary Open Angle Glaucoma Proteins Reactive Oxygen Species Reporter Role Stress Time Tissues Trabecular meshwork structure Transmission Electron Microscopy Work endoplasmic reticulum stress improved in vivo in vivo Model insight mitochondrial dysfunction mouse model novel prevent transcription factor treatment strategy

项目摘要

Abstract Primary Open Angle Glaucoma (POAG) is the most common form of glaucoma that leads to irreversible vision loss. Elevated intraocular pressure (IOP) due to dysfunction of trabecular meshwork (TM) tissue is a hallmark of POAG. However, the pathological mechanisms leading to TM dysfunction and IOP elevation are poorly understood. Our recent studies have shown that chronic endoplasmic reticulum (ER) stress is associated with the pathophysiology of glaucomatous TM damage and IOP elevation. However, the exact mechanisms of TM cell dysfunction/loss are not completely understood. The ER and mitochondria communicate constantly via mitochondria-associated ER membranes (MAMs) to regulate vital cellular functions including autophagy. Autophagy degrades long-lived proteins and damaged organelles including mitochondria (known as mitophagy) via lysosomes. Impaired mitophagy is known to cause abnormal accumulation of damaged mitochondria resulting into cell death. In our preliminary studies, primary human TM cells exhibited an abundant mitochondria and MAMs. Interestingly, human primary TM cells and TM tissues from POAG donor eyes demonstrated increased accumulation of mitochondria. Moreover, chronic ER stress-induced transcriptional factors, ATF4 and CHOP led to increased reactive oxygen species and impaired mitophagy in primary human TM cells. Our overall goals are to define the role of MAMs and impaired mitophagy in TM dysfunction and IOP elevation in POAG and to further target these pathways for the treatment of glaucoma. We hypothesize that chronic ER stress induces impaired mitophagy and mitochondrial dysfunction, leading to TM dysfunction/loss and IOP elevation in POAG. We will determine whether impaired mitophagy and mitochondrial dysfunction are associated with TM dysfunction and IOP elevation in human and mouse glaucoma (Aim 1). We will further determine whether chronic ER stress induces impaired mitophagy and mitochondrial dysfunction, leading to TM dysfunction/loss and IOP elevation (Aim 2). Finally, we will perform proof-of-principle studies exploring whether the mitophagy enhancers improve outflow facility and reduce elevated IOP in mouse models of glaucoma (Aim 3). We will utilize human primary TM cells and post-mortem TM tissues from normal and glaucoma donor eyes, mouse models of glaucoma and mitophagy flux reporter mouse model (mito-qc) as well as transmission electron microscopy (TEM) and the Seahorse assays to determine the role of MAMs, mitophagy and mitochondrial dysfunction in TM function and IOP homeostasis. The successful completion of the proposed studies will provide novel crosstalk between ER stress and mitophagy and target the pathological mechanisms for the treatment of general POAG.

抽象的初级开角青光眼（POAG）是最常见的青光眼形式，导致不可逆转的视力损失。由于小梁网（TM）组织的功能障碍引起的眼内压（IOP）是一个标志 Poag。但是，导致TM功能障碍和IOP升高的病理机制很差理解。我们最近的研究表明，慢性内质网应力与青光眼TM损伤和IOP升高的病理生理。但是，TM的确切机制细胞功能障碍/丢失尚不完全了解。急诊室和线粒体通过线粒体相关的ER膜（MAMS）调节包括自噬在内的重要细胞功能。自噬降解长寿命的蛋白质和包括线粒体在内的受损细胞器（称为线粒体）通过溶酶体。线粒体受损会导致线粒体受损异常的积累导致细胞死亡。在我们的初步研究中，原代人TM细胞表现出丰富的线粒体和妈妈。有趣的是，POAG供体眼中的人类原代TM细胞和TM组织显示线粒体的积累增加。此外，慢性ER应力诱导的转录因子ATF4和 CHOP导致活性氧增加并在原代人TM细胞中损害线细胞。我们的整体目标是定义妈妈的作用和线粒体在TM功能障碍中的作用，以及POAG和进一步以这些途径来治疗青光眼。我们假设慢性ER应力引起线粒体和线粒体功能障碍受损，导致TM功能障碍/损失和IOP升高。我们将确定线粒体和线粒体功能障碍是否与TM相关人和小鼠青光眼的功能障碍和IOP升高（AIM 1）。我们将进一步确定是否慢性 ER应力会引起线粒体和线粒体功能障碍受损，导致TM功能障碍/损失，IOP 高程（目标2）。最后，我们将进行原则研究，以探讨线索增强剂是否改善流出设施并减少青光眼小鼠模型中的IOP升高（AIM 3）。我们将利用人类来自正常和青光眼供体眼的原代TM细胞和验尸TM组织，小鼠模型青光眼和线粒体通量报告基因模型（MITO-QC）以及透射电子显微镜（TEM）和海马测定法确定TM中MAM，线粒体和线粒体功能障碍的作用功能和IOP稳态。拟议研究的成功完成将提供新颖的串扰在ER应力和线粒体之间，靶向一般POAG治疗的病理机制。