Mitochondrial Oxidative Stress in the Retinal Pigment Epithelium as a Model for A

视网膜色素上皮中的线粒体氧化应激作为 A 的模型

• 批准号: 8448256
• 负责人: Alfred S Lewin
• 金额: $ 50.23万
• 依托单位: UNIVERSITY OF FLORIDA
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-03-01 至 2016-02-29
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8448256
• 关键词: Adult; Affect; Age related macular degeneration; Aging; Alleles; Antioxidants; Apoptosis; Area; Atrophic; Behavioral; Blindness; Bruch' s basal membrane structure; Catalytic RNA; Cell physiology; Cells; Choroidal Neovascularization; Complement; Country; DNA; Disease; Elderly; Electrophysiology (science); Elements; Energy Metabolism; Enzyme Gene; Enzymes; Exhibits; Exudative age-related macular degeneration; Eye; Fluorescein Angiography; Functional disorder; Fundus; Gene Transfer; Genes; Genetic Predisposition to Disease; Glutathione S-Transferase; Goals; Human; Image; Inflammation Process; Inflammatory; Knock-out; Lead; Learning; Life; Lipofuscin; Localized Disease; Measures; Mitochondria; Modeling; Monitor; Mus; Mutation; NAD(P)H dehydrogenase (quinone) 1, human; Neonatal; Neural Retina; Nonexudative age-related macular degeneration; Optical Coherence Tomography; Oral; Oxidative Stress; Pathologic; Pathology; Pathway interactions; Patients; Peripheral; Pharmaceutical Preparations; Photoreceptors; Play; Process; Proteins; RNA; Reactive Oxygen Species; Resolution; Response Elements; Retina; Retinal; Retinal Cone; Retinal Degeneration; Role; SOD2 gene; Sampling; Site; Source; Staging; Structure of retinal pigment epithelium; Susceptibility Gene; System; Testing; Time; Transcription factor genes; United States; Up-Regulation; Vascular Endothelial Growth Factors; Viral; adduct; base; effective therapy; geographic atrophy; heme oxygenase-1; human SOD2 protein; improved; in vivo; inhibitor/antagonist; macula; morphometry; mouse model; novel; oxidative damage; prevent; public health relevance; recombinase; research study; response; retinal damage; stem; transcription factor

DESCRIPTION (provided by applicant): Age Related Macular Degeneration (AMD) is a major blinding disease of the elderly in this country and, while VEGF inhibitors often stem the late, exudative stages of the disease, there is no effective therapy for the earlier, atrophic form of AMD. Oxidative damage to the retinal pigment epithelium (RPE) contributes to AMD by reducing the function of these cells and by stimulating an inflammatory cascade that leads to the pathologic hallmarks of the disease, localized atrophy of the retina and choroidal neovascularization. One source of the RPE- damaging reactive oxygen species (ROS) are the mitochondria of the RPE cells themselves. To determine whether mitochondria are an important source of ROS in the RPE in vivo, the SOD2 gene, encoding the protective enzyme MnSOD, will be deleted specifically in the RPE of mice, using a mouse line containing an allele of SOD2 flanked by loxP sites and RPE-specific expression of Cre recombinase. We plan 3 sets of experiments: (1) We will monitor the time course of retinal degeneration in real time in living mice using electrophysiology (ERG), high resolution structural analysis (SD-OCT) and behavioral analysis (Optomotry). In post mortem samples, we will examine morphological changes to the RPE, Bruch's membrane and the neural retina and to measure accumulation of lipofuscin in the RPE. We will induce the deletion of SOD2 both in neonatal and in adult mice to determine which approach better models human geographic atrophy. (2) We will increase mitochondrial oxidative stress by deletion of SOD2 in mice bearing a homozygous mutation in the gene for the transcription factor Nrl. These mice have a cone-only retina which may resemble the cone-rich human macula better than the normal mouse retina. By this means we hope to learn why the central retina is more sensitive to oxidative stress than the peripheral retina. (3) We will attempt to counteract mitochondrial oxidative stress by elevating a set of antioxidant enzymes, including heme oxygenase-1, glutathione transferases, and NAD(P)H:quinone oxidoreductase 1. These genes for these enzymes contain a common sequence component denoted "ARE" for antioxidant sequence element. We will stimulate this antioxidant response in two ways-by viral delivery of a gene that stimulates the response and by oral delivery of a novel drug that activates this pathway. We hope that these approaches may lead to a therapy for the atrophic form of AMD.

描述（由申请人提供）：年龄相关性黄斑变性 (AMD) 是该国老年人的一种主要致盲疾病，虽然 VEGF 抑制剂通常可以阻止该疾病的晚期、渗出阶段，但对于早期、渗出阶段没有有效的治疗方法。 AMD 的萎缩型。视网膜色素上皮 (RPE) 的氧化损伤会降低这些细胞的功能，并刺激炎症级联反应，从而导致该疾病的病理特征，即视网膜局部萎缩和脉络膜新生血管形成，从而导致 AMD。 RPE 损伤性活性氧 (ROS) 的来源之一是 RPE 细胞本身的线粒体。为了确定线粒体是否是体内 RPE 中 ROS 的重要来源，将使用包含侧翼为 loxP 位点的 SOD2 等位基因的小鼠品系，在小鼠 RPE 中特异性删除编码保护酶 MnSOD 的 SOD2 基因，以及Cre 重组酶的 RPE 特异性表达。我们计划进行3组实验：（1）我们将利用电生理学（ERG）、高分辨率结构分析（SD-OCT）和行为分析（Optomotry）实时监测活体小鼠视网膜变性的时间进程。在尸检样本中，我们将检查 RPE、布鲁赫膜和神经视网膜的形态变化，并测量 RPE 中脂褐质的积累。我们将在新生小鼠和成年小鼠中诱导 SOD2 缺失，以确定哪种方法可以更好地模拟人类地理萎缩。 (2) 我们将通过在转录因子 Nrl 基因纯合突变的小鼠中删除 SOD2 来增加线粒体氧化应激。这些小鼠的视网膜只有视锥细胞，可能比正常小鼠的视网膜更类似于富含视锥细胞的人类黄斑。通过这种方式，我们希望了解为什么中央视网膜比周边视网膜对氧化应激更敏感。 (3) 我们将尝试通过提高一组抗氧化酶来对抗线粒体氧化应激，包括血红素加氧酶-1、谷胱甘肽转移酶和 NAD(P)H:醌氧化还原酶 1。这些酶的这些基因包含一个共同的序列组件，表示为“ARE”代表抗氧化序列元件。我们将通过两种方式刺激这种抗氧化反应——通过病毒传递刺激反应的基因，以及通过口服传递激活该途径的新药。我们希望这些方法能够治疗萎缩性 AMD。