Role of Oxidative Stress in Pathogenesis of Fuchs Endothelial Corneal Dystrophy

氧化应激在福克斯内皮性角膜营养不良发病机制中的作用

• 批准号: 9319755
• 负责人: Ula V. Jurkunas
• 金额: $ 48.68万
• 依托单位: SCHEPENS EYE RESEARCH INSTITUTE
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-07-01 至 2020-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9319755
• 关键词: Agonist; Antioxidants; Apoptosis; Base Excision Repairs; Biogenesis; Blindness; Cell Aging; Cell Death; Cell Line; Cell Nucleus; Cells; Characteristics; Chronic; Cornea; Corneal Endothelium; Corneal edema; DNA Adduction; DNA Adducts; DNA Damage; DNA Repair; Data; Deposition; Descemet' s membrane; Development; Disease; Elderly; Endothelial Cells; Endothelium; Enzymes; Estrogen Metabolism; Estrogens; Etiology; Extracellular Matrix; Female; Fuchs' Endothelial Dystrophy; Genetic Transcription; Grant; Human; Impairment; In Vitro; Incidence; Investigation; Ion Pumps; Keratoplasty; Knockout Mice; Laboratories; Lead; Lesion; Light; Link; Mesenchymal; Mitochondria; Mitochondrial DNA; Modeling; Morphology; Mus; NADP; NF-E2-related factor 2; Nuclear; Oxidants; Oxidative Stress; Pathogenesis; Pathogenicity; Pathway interactions; Patients; Pharmacological Treatment; Predisposition; Process; Pump; Quinones; Role; Severities; Signal Pathway; Telomerase; Tissues; UVA induced; Woman; age related; base; cytotoxic; enzyme pathway; genotoxicity; human old age (65+); in vivo; irradiation; male; mitochondrial dysfunction; oxidative DNA damage; prevent; public health relevance; repaired; response; ultraviolet

 DESCRIPTION (provided by applicant): Fuchs Endothelial Corneal Dystrophy (FECD), a common age-related dystrophy, which is more prevalent in women, is of unknown etiology. In FECD, corneal endothelial (CE) cell loss is accompanied by abnormal extracellular matrix (ECM) deposition in the form of guttae. Our laboratory was the first to link oxidative stress with FECD pathogenesis. Specifically, we showed that in FECD, oxidant-antioxidant imbalance due to suboptimal Nrf2-regulated antioxidant defense, including a decline in its transcriptional target NQO1, leads to oxidative DNA damage, mitochondrial dysfunction, and apoptosis. However, little is known regarding the mechanism of guttae formation and the predominance of FECD development in women. The mechanism of the observed DNA damage in cellular degeneration in FECD is not known. Building upon our previous findings, we propose to investigate if oxidant-antioxidant imbalance in FECD leads to endothelial mesenchymal transition (EMT) with concomitant ECM deposition, and if this imbalance causes the formation of cytotoxic estrogen metabolites, which are known to accumulate in tissues with the defective Nrf2-NQO1 and cause DNA damage, more commonly in women. Since our preliminary studies indicate a defective DNA damage response (DDR) in FECD, we will determine whether it leads to decreased DNA damage repair, cellular senescence, and apoptosis. Our proposal seeks to explore three different disease mechanisms: EMT, estrogen genotoxicity, and DDR, all of which either independently or collectively may lead to the development of FECD. Our study is significant, as the investigation of the mechanisms involved in the oxidative stress-induced cellular damage will provide new treatment targets for FECD. In order to achieve these aims, we will use our newly developed telomerase-immortalized human CE cells and the in vivo oxidative stress model based on the ultraviolet-A irradiation of mouse corneas. This model is specifically relevant to our study since it replicates in mice the CE morphological changes with guttae-like lesions and apoptosis, characteristically seen in FECD patients. Our Specific Aims are: Aim 1: Determine whether oxidant-antioxidant imbalance seen in FECD activates EMT that leads to aberrant ECM deposition seen in guttae. This aim is based on the hypothesis that in FECD chronic oxidative stress causes endothelial cells to undergo EMT and enhanced ECM deposition leading to guttae formation that can be modified by activation of Nrf2 pathway. Aim 2: Investigate the role of reactive estrogen metabolites in initiating an estrogen genotoxic pathway that may account for higher incidence and severity of FECD in women. This aim is based on the hypothesis that altered levels of estrogen-metabolizing enzymes lead to imbalanced estrogen metabolism and increased formation of depurinating estrogen-DNA adducts in FECD. Aim 3: Investigate the role of DDR on mitochondrial and nuclear DNA repair during oxidative stress- induced damage of CE in FECD. This aim is based on the hypothesis that impaired DDR leads to deficient DNA repair that results in mitochondrial dysfunction, cellular senescence, and apoptosis.

 描述(申请人提供)：Fuchs内皮性角膜营养不良(FECD)，一种常见的年龄相关性营养不良，更常见于女性，病因不明。在FECD中，角膜内皮(CE)细胞丢失伴随着以牙胶形式存在的异常细胞外基质(ECM)沉积。我们实验室首次将氧化应激与FECD发病机制联系起来。具体地说，我们发现，在FECD中，氧化-抗氧化失衡是由于Nrf2调节的次优抗氧化防御，包括其转录目标的下降 NQO1导致DNA氧化损伤、线粒体功能障碍和细胞凋亡。然而，关于牙胶形成的机制和FECD在女性中的优势发展，人们知之甚少。观察到的DNA损伤在FECD细胞退变中的机制尚不清楚。基于我们之前的发现，我们建议调查FECD中的氧化-抗氧化失衡是否会导致内皮间质转化(EMT)并伴随ECM沉积，以及这种失衡是否会导致细胞毒性雌激素代谢物的形成，已知雌激素代谢物会积聚在Nrf2-NQO1缺陷的组织中，并导致DNA损伤，这在女性中更常见。由于我们的初步研究表明FECD的DNA损伤反应(DDR)存在缺陷，我们将确定它是否会导致DNA损伤修复减少、细胞衰老和细胞凋亡。我们的建议旨在探索三种不同的疾病机制：EMT、雌激素遗传毒性和DDR，所有这些机制都可能独立或共同导致FECD的发展。我们的研究意义重大，因为对氧化应激诱导的细胞损伤机制的研究将为FECD提供新的治疗靶点。为了达到这些目的，我们将使用我们新开发的端粒酶永生化的人CE细胞和基于紫外线-A辐射的小鼠角膜体内氧化应激模型。这个模型与我们的研究特别相关，因为它在小鼠身上复制了CE的形态变化，具有滴状病变和细胞凋亡，这是FECD患者特有的。我们的具体目标是：目标1：确定FECD中出现的氧化-抗氧化失衡是否激活了EMT，从而导致在牙胶中出现异常的ECM沉积。这一目的是基于这样一种假设：在FECD中，慢性氧化应激导致内皮细胞经历EMT，并增加ECM沉积，导致牙胶形成，这种形成可以通过激活Nrf2途径来修改。目的：研究反应性雌激素代谢产物在启动雌激素遗传毒性途径中的作用，该途径可能是女性FECD发病率和严重程度较高的原因。这一目的是基于这样一种假设，即雌激素代谢酶水平的改变会导致雌激素代谢失衡，并增加FECD中净化雌激素-DNA加合物的形成。目的：探讨DDR在氧化应激致FECD细胞损伤过程中对线粒体和核DNA修复的影响。这一目的是基于这样一种假设，即DDR受损会导致DNA修复缺陷，从而导致线粒体功能障碍、细胞衰老和细胞凋亡。