Regulation of Retinal Cell Death in Diabetes

糖尿病视网膜细胞死亡的调节

基本信息

批准号：
9124905
负责人：
Steven F Abcouwer
金额：
$ 55.76万
依托单位：
UNIVERSITY OF MICHIGAN AT ANN ARBOR
依托单位国家：
美国
项目类别：
财政年份：
2010
资助国家：
美国
起止时间：
2010-05-01 至 2019-08-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9124905
关键词：
Address Adult Affect Apoptosis Area Blindness Blood Vessels Brain Cell Death Cell Survival Cell physiology Cells Cessation of life Color Visions Complex Contrast Sensitivity Data Defect Diabetes Mellitus Diabetic Retinopathy Diabetic mouse Disease Enzymes Equilibrium Exhibits Eye FRAP1 gene Functional disorder Genes Genetic Translation Glaucoma Goals Grant Health Human Hyperglycemia Insulin Insulin Receptor Knock-out Knowledge Lead Left LoxP-flanked allele Mediating Mission Modification Molecular Morphology Mus Nerve Degeneration Neural Retina Nutrient Optic Nerve Injuries Pathology Pathway interactions Patients Persons Phosphorylation Phosphotransferases Polyribosomes Population Pre-Clinical Model Preventive treatment Protein Biosynthesis Protein Phosphatase 2A Regulatory Subunit PR53 Protein phosphatase Proteins Public Health Rapamycin-Binding Proteins Raptors Rattus Receptor Signaling Regulation Research Retina Retinal Retinal Diseases Retinal Ganglion Cells Rodent Rodent Model Role Signal Pathway Signal Transduction Specificity Staging Synapses Techniques Testing Vision Visual Visual impairment Western Blotting Work axonal degeneration bevacizumab clinically relevant diabetic diabetic rat disability improved in vivo innovation knock-down loss of function macular edema member neuron loss neurosensory neurovascular unit novel protein degradation protein expression receptor recombinase research study retinal neuron targeted treatment vector

项目摘要

DESCRIPTION (provided by applicant): There is a fundamental gap in understanding how diabetes impacts the retinal neurons that provide vision. Because of this, current therapies intervene in latter stages of the disease, when blood vessels are affected. Anti-VEGF therapy limits damage in advanced diabetic retinopathy (DR), but does not address damage to the neurosensory retina. Hence, the long-term goal of this project is to define the mechanisms that cause retinal ganglion cell (RGC) dysfunction in patients with DR. The overall objective is to define the roles of mechanistic target of rapamycin complex 2 (mTORC2) signaling in the interactions between hyperglycemia and protein synthesis that lead to RGC dysfunction and subsequent vision loss in DR. The project will utilize diabetic rats and mice, which are the standard pre-clinical models of DR, and which exhibit the early neurodegenerative changes of human DR. The central hypothesis is that diabetes-induced defects in mTORC2 signaling impair protein synthesis, axonal function and survival of retinal ganglion cells. The rationale for this work is that identifying pathways causing RGC dysfunction and death will ultimately lead to preventive treatments and better vision for persons with diabetes. The hypothesis is supported by strong preliminary data showing: 1) prominent mTOR and Rictor expression in RGCs; 2) reduced mTOR expression in diabetic human donor eyes; and 3) the ability to conditionally knockout of Rictor expression in adult mice. The hypothesis will be tested in two specific aims: 1) to define the mechanisms by which diabetes impairs retinal mTORC2 activity and the cell-specific effects of diabetes on protein synthesis, and 2) to define the consequences of impaired mTORC2 activity on retinal ganglion cell protein synthesis, survival and morphology. The first aim will examine the effect of diabetes on mTORC2 complex member protein expression in human retinas, use diabetic rodent models to determine the molecular mechanisms by which diabetes reduces retinal mTORC2 activity and protein synthesis, and examine the cell-specificity of these effects. The second aim will employ in vivo spatial and cell- specific targete loss-of-function studies to disrupt mTORC complexes by knockout of the mTOR-associated proteins Rictor and Raptor in inner retinal neurons and determine the effects on protein turnover, axonal function and cell survival. The proposal is innovative because it: 1) expands the novel observation of diminished mTORC2 activity in DR and investigates the unexplored area of mTOR function in the neural retina; 2) will be the first to examine the cell-specific alterations i retinal mTORC complexes and protein synthesis leading to loss of neuronal integrity in DR; and 3) will use innovative techniques, including translatomics to define cell-specific changes in retinal mRNA translation, and targeted AAV-cre recombinase vectors to delete Rictor, Raptor and protein phosphatase PP2A genes in RGC. The work is significant because it will elucidate clinically relevant means to restore defective signaling pathways responsible for loss of RGC function in retinal diseases that have universal importance to vision and implications for the NEI Audacious Goals Initiatives.

描述（由申请人提供）：在理解糖尿病如何影响提供视力的视网膜神经元方面存在根本性的差距，因此，当前的疗法在血管受到影响时进行干预。在晚期糖尿病视网膜病变（DR）中，但不解决神经感觉视网膜损伤的问题，因此，该项目的长期目标是确定导致糖尿病患者视网膜神经节细胞（RGC）功能障碍的机制。 DR. 总体目标是确定雷帕霉素复合物 2 (mTORC2) 信号传导在高血糖和蛋白质合成之间相互作用中的作用，从而导致 DR 中的 RGC 功能障碍和随后的视力丧失。这是标准的 DR 临床前模型，展示了人类 DR 的早期神经退行性变化。核心假设是糖尿病引起的 mTORC2 信号缺陷会损害蛋白质合成，这项工作的基本原理是，确定导致 RGC 功能障碍和死亡的途径将最终为糖尿病患者带来预防性治疗和更好的视力，该假设得到了强有力的初步数据的支持，这些数据显示：1）显着。 RGC 中的 mTOR 和 Rictor 表达；2) 糖尿病人类供体眼睛中 mTOR 表达减少；以及 3) 在成年小鼠中条件性敲除 Rictor 表达的能力。确定糖尿病损害视网膜 mTORC2 活性的机制以及糖尿病对蛋白质合成的细胞特异性影响，以及 2) 确定 mTORC2 活性受损对视网膜神经节细胞蛋白质合成、存活和形态的影响。糖尿病对人视网膜 mTORC2 复合体成员蛋白表达的影响，使用糖尿病啮齿动物模型确定糖尿病降低视网膜 mTORC2 活性和蛋白质合成的分子机制，并检查第二个目标是利用体内空间和细胞特异性靶点功能丧失研究，通过敲除视网膜内神经元中的 mTOR 相关蛋白 Rictor 和 Raptor 来破坏 mTORC 复合物，并确定对这些效应的影响。该提议具有创新性，因为它：1）扩展了 DR 中 mTORC2 活性减弱的新观察，并研究了神经视网膜中 mTOR 功能的未探索区域； 2) 将率先检查视网膜 mTORC 复合物和蛋白质合成中导致 DR 神经元完整性丧失的细胞特异性改变；3) 将使用创新技术，包括翻译组学来定义视网膜 mRNA 翻译的细胞特异性变化，以及靶向 AAV-cre 重组酶载体以删除 RGC 中的 Rictor、Raptor 和蛋白磷酸酶 PP2A 基因。这项工作意义重大，因为它将阐明临床相关方法。恢复导致视网膜疾病中 RGC 功能丧失的有缺陷的信号通路，这些信号通路对视力具有普遍重要性，并对 NEI 大胆目标倡议具有重要意义。