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（由适用提供）：了解糖尿病如何影响提供视力的残留神经元存在基本差距。因此，当血管受到影响时，当前的疗法干预了该疾病的晚期。抗VEGF疗法限制了晚期糖尿病性视网膜病（DR）的损害，但不能解决对神经感觉视网膜的损害。因此，该项目的长期目标是定义DR患者中引起重复神经节细胞（RGC）功能障碍的机制。总体目的是定义雷帕霉素复合物2（MTORC2）信号在高血糖和蛋白质合成之间的相互作用中的机械靶标的作用，从而导致RGC功能障碍以及随后在DR中的视觉丧失。该项目将利用糖尿病大鼠和小鼠，这是DR的标准临床前模型，并暴露了人类DR的早期神经退行性变化。中心假设是MTORC2信号传导中糖尿病诱导的缺陷会损害视网膜神经节细胞的蛋白质合成，轴突功能和存活。这项工作的理由是，确定引起RGC功能障碍和死亡的途径最终将导致预防性治疗，并为糖尿病患者提供更好的视力。该假设得到了强大的初步数据的支持：1）RGC中突出的MTOR和Richtor表达； 2）糖尿病人类供体眼中MTOR表达降低； 3）有条件地敲除成年小鼠中Richtor表达的能力。该假设将以两个具体的目的进行检验：1）定义糖尿病损害残留MTORC2活性的机制和糖尿病对蛋白质合成的细胞特异性作用，以及2）定义了残留的MTORC活性对残余神经节细胞蛋白质蛋白质合成，生存和神经术的影响的后果。第一个目的将检查糖尿病对人视网膜中MTORC2复合成员蛋白表达的影响，使用糖尿病啮齿动物模型来确定糖尿病降低残留MTORC2活性和蛋白质合成的分子机制，并检查这些作用的细胞特异性。第二个目的将利用体内空间和细胞特异性靶向功能丧失研究来破坏MTORC复合物，通过在内部残留神经元中敲除MTOR相关蛋白Richtor和Raptor，并确定对蛋白质离职，轴突功能，轴突功能和细胞存活的影响。该提案具有创新性，因为它：1）扩大了对DR中MTORC2活性降低的新颖观察结果，并研究了神经元视网膜中MTOR功能的意外区域； 2）将是第一个检查细胞特异性改变I视网膜MTORC复合物和蛋白质合成的人，从而导致DR中神经元完整性的丧失； 3）将使用创新技术，包括翻译学来定义视网膜mRNA翻译的细胞特异性变化，并靶向AAV-CRE重组酶载体来删除RGC中Richtor，Raptor和蛋白质磷酸酶PP2A基因。这项工作很重要，因为它将阐明临床上相关的手段，以恢复导致RGC功能在残留疾病中丧失的有缺陷的信号通路，这些残余疾病对视力和对Nei Audiacy目标计划的影响至关重要。