Oxidative stress and innate immunity impair the visual cycle

项目摘要 视网膜相关性黄斑变性（AMD）是老年人失明的主要原因。目前没有 治疗将恢复任何形式的AMD的视力。为了弥补这一缺陷，本提案将侧重于 可以恢复视力的机制。11-cRAL通过视觉循环的再循环是RPE 这对视力至关重要。氧化应激和补体是AMD发病的重要因素 病理生理学，它们对视觉周期的影响是不确定的。本提案的目的是确定如何 氧化应激和先天免疫损害了AMD的视觉周期，从而降低了视力。假设是 氧化应激和受损的补体调节因子Cfh和CD 46降低了视觉周期 网络建议的具体目标是：1。确定氧化应激i）损害Cfh诱导的程度 炎症降低视觉周期基因表达，和ii）诱导Ptx 3，并通过调节Cfh 丰富，防止视觉周期下降。这一目标将测试Cfh减少产生的程度 炎症来自补体或MDA介导的细胞因子表达增加以激活Stat 3， 降低视觉周期基因表达、功能和视力，Ptx 3对Cfh丰度的影响， 调节Cfh介导的炎症。2.确定慢性氧化应激损害视觉的程度 通过Notch信号循环。氧化应激激活Notch信号，其可以诱导转录 因子Sox 9来控制6个视觉周期基因的网络表达。当急性Notch信号传导 增加Sox 9，慢性Notch信号降低Sox 9。这一目标将探讨慢性氧化性 应激激活Notch信号，以及Notch如何通过Sox 9影响视觉周期功能。3.确定 CD 46调节Notch信号传导和Sox 9介导的视觉周期基因功能的程度。除了其 在补体调节作用中，CD 46结合Jag 1以阻碍Notch信号传导。因此，CD 46的减少使 Jag 1可激活Notch信号传导作为替代的非互补功能。这一目标将探讨 CD 46的减少通过Jag 1影响Notch信号通路和视觉周期功能。因为CD 46是 在啮齿动物体细胞中不表达，我们将使用在关键CD 46结构域中具有突变的iPS RPE细胞， 解决这个目标。这些贡献是重要的，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。这项研究是创新的，因为我们将调查未充分研究的领域 包括氧化应激和先天免疫的协同作用导致视力丧失的机制， Stat 3、Notch和Sox 9的作用，以及补体调节因子的非常规、非补体功能， 视觉周期使用独特的，最先进的基因小鼠，具有新鲜的，但决定性的因素， 之前测试过。靶向治疗，中和降解视觉周期基因表达的途径， 功能和视觉的氧化应激和过度活跃的先天免疫，预计将导致这项工作。

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.