Oxidative stress and innate immunity impair the visual cycle

氧化应激和先天免疫会损害视觉周期

• 批准号: 9260322
• 负责人: James T Handa
• 金额: $ 52.76万
• 依托单位: JOHNS HOPKINS UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-03-01 至 2022-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9260322
• 关键词: 11 cis Retinal; Acute; Address; Affect; Age related macular degeneration; Antioxidants; Area; Binding; Blindness; CD46 Antigen; Cells; Chronic; Complement; Complement Activation; Data; Disease; Elderly; Epithelial; Epitopes; Functional disorder; Gene Expression; Genes; Genetic; Impairment; Inflammation; Inflammatory; Injection of therapeutic agent; Injury; Ligands; Link; Literature; Malondialdehyde; Mediating; Micronutrients; Mus; Mutation; Natural Immunity; Oxidative Stress; Pathway interactions; Recycling; Research; Retina; Retinal Pigments; Risk; Rodent; Role; Signal Transduction; Structure of retinal pigment epithelium; System; Testing; Vision; Visual; Visual Pathways; Visual impairment; Work; aging population; bevacizumab; cytokine; design; effective therapy; gene function; induced pluripotent stem cell; innovation; neovascular; notch protein; novel; prevent; retinal damage; targeted treatment; transcription factor; visual control; visual cycle

Project Summary Age-related macular degeneration (AMD) is the leading cause of blindness among the elderly. At present, no therapy will restore vision with any form of AMD. To address this shortcoming, this proposal will focus on mechanisms that could restore vision. The recycling of 11-cis-retinal (11-cRAL) by the visual cycle is an RPE function that is essential for vision. While oxidative stress and complement are integral factors in AMD pathophysiology, their impact on the visual cycle is undefined. The objective of this proposal is to define how oxidative stress and innate immunity impair the visual cycle to decrease vision in AMD. The hypothesis to be tested is that oxidative stress and impaired complement regulators Cfh and CD46 decrease the visual cycle network. The proposed specific aims are: 1. Determine the extent that oxidative stress i) impairs Cfh to induce inflammation which decreases visual cycle gene expression, and ii) induces Ptx3, and by regulating Cfh abundance, prevents visual cycle decline. This aim will test the extent that decreased Cfh generates inflammation from increased complement or MDA mediated cytokine expression to activate Stat3, which decreases visual cycle gene expression, function, and vision, and the impact of Ptx3 on Cfh abundance to regulate Cfh mediated inflammation. 2. Determine the extent that chronic oxidative stress impairs the visual cycle through Notch signaling. Oxidative stress activates Notch signaling, which can induce the transcription factor Sox9 to control the expression of a network of 6 visual cycle genes. While acute Notch signaling increases Sox9, chronic Notch signaling decreases Sox9. This aim will explore the extent that chronic oxidative stress activates Notch signaling, and how Notch influences visual cycle function through Sox9. 3. Determine the extent that CD46 regulates Notch signaling and Sox9 mediated visual cycle gene function. Besides its complement regulatory action, CD46 binds Jag1 to impede Notch signaling. Thus, decreased CD46 makes Jag1 available to activate Notch signaling as an alternative, non-complement function. This aim will explore the extent that decreased CD46 influences Notch signaling and visual cycle function through Jag1. Since CD46 is not expressed in somatic rodent cells, we will use iPS RPE cells with mutations in key CD46 domains to address this aim. These contributions are significant because if successful, novel pathways will be identified as targets to treat vision loss in AMD. The research is innovative since we will investigate understudied areas including mechanisms of vision loss from the synergistic impact of oxidative stress and innate immunity, the role of Stat3, Notch, and Sox9, and unconventional, non-complement functions of complement regulators on the visual cycle using unique, state-of-the-art genetic mice with fresh, but decisive factors that have not been previously tested. Targeted therapy that neutralizes pathways that degrade visual cycle gene expression, function, and vision from oxidative stress and overactive innate immunity is expected to result from this work.

项目摘要 与年龄相关的黄斑变性（AMD）是老年人失明的主要原因。目前，没有 治疗将以任何形式的AMD恢复视力。为了解决这一缺点，该提议将重点放在 可以恢复视力的机制。通过视觉循环对11-CIS-视视网膜（11克）的回收是RPE 对视觉至关重要的功能。而氧化应激和补体是AMD中不可或缺的因素 病理生理学，它们对视觉周期的影响不确定。该提议的目的是定义如何 氧化应激和先天免疫会损害视觉周期，以降低AMD的视力。假设是 测试的是氧化应激和补体调节器CFH和CD46减少视觉周期 网络。提出的特定目的是：1。确定氧化应激的程度i）损害CFH诱导CFH 降低视觉周期基因表达的炎症，ii）诱导PTX3，并通过调节CFH 丰度，防止视觉周期下降。此目标将测试降低CFH生成的程度 补体增加或MDA介导的细胞因子表达而激活STAT3的炎症，这 降低视觉循环基因表达，功能和视觉，以及PTX3对CFH丰度的影响 调节CFH介导的炎症。 2。确定慢性氧化应激会损害视觉的程度 通过Notch信号循环。氧化应力激活Notch信号，这可以诱导转录 因子Sox9控制6个视觉循环基因网络的表达。而急性凹口信号传导 增加Sox9，慢性置口信号传导降低了Sox9。这个目标将探索慢性氧化的程度 应力激活Notch信号传导，以及Notch如何通过SOX9影响视觉周期功能。 3。确定 CD46调节Notch信号传导和SOX9介导的视觉周期基因功能的程度。除了它 补体调节作用，CD46结合JAG1以阻碍Notch信号传导。因此，CD46减少 JAG1可用于激活Notch信号作为替代性的，不配合的函数。这个目标将探索 降低CD46的程度会通过JAG1影响Notch信号传导和视觉循环函数。因为CD46是 在体细胞中不表达，我们将使用与关键CD46域中突变的IPS RPE单元 解决这个目标。这些贡献很重要，因为如果成功，新的途径将被确定为 治疗AMD视力丧失的目标。这项研究具有创新性，因为我们将调查研究不足的领域 包括氧化应激和先天免疫的协同影响，视力丧失的机制， STAT3，Notch和Sox9的作用，以及不合常规的补体调节器在不合格的功能上 使用独特的，最先进的遗传小鼠具有新鲜但果断的因素的视觉周期 先前已测试。靶向疗法中和降低视觉循环基因表达的途径， 这项工作有望产生功能以及氧化应激和过度活跃的先天免疫力的视力。