Thioredoxin interacting protein is critical for development of early diabetic retinopathy

硫氧还蛋白相互作用蛋白对于早期糖尿病视网膜病变的发展至关重要

• 批准号: 9886912
• 负责人: LALIT SINGH PUKHRAMBAM
• 金额: $ 30.8万
• 依托单位: WAYNE STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-12-02 至 2022-07-29
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9886912
• 关键词: Address; Anabolism; Antioxidants; Autophagocytosis; Bioenergetics; Biogenesis; Blindness; Cathepsins; Cause of Death; Cell Death; Cells; Cessation of life; Chronic; Complex; Complication; Confocal Microscopy; Consumption; DNA; Development; Diabetes Mellitus; Diabetic Retinopathy; Electron Transport; Electrons; Environment; Equilibrium; Excision; Eye; Functional disorder; Funding; Gene Expression; Genes; Genetic Transcription; Glucose; Glutathione; Homeostasis; In Vitro; Injury; Interphase Cell; Iron; Laboratories; Lead; Legal patent; Light; Link; Lipid Peroxidation; Lysosomes; Measures; Mediating; Mediator of activation protein; Membrane Lipids; Membrane Proteins; Mitochondria; Mitochondrial Membrane Protein; Mitochondrial Proteins; Molecular; Monitor; Morphology; Muller' s cell; Neuraxis; Neurodegenerative Disorders; Neuroglia; Neurons; Nuclear Translocation; Nucleic Acids; Organelles; Outer Mitochondrial Membrane; Oxidative Stress; Oxygen; Paris, France; Pathogenesis; Pathway interactions; Permeability; Photoreceptors; Physiological; Pigment Epithelium; Play; Process; Production; Protein Kinase; Proteins; Publishing; Quality Control; Reactive Oxygen Species; Regulation; Research; Retina; Role; Stimulation of Cell Proliferation; Stress; Structure of retinal pigment epithelium; TXNIP gene; Technology; Testing; Transcription Initiation Site; Transcriptional Activation; Transcriptional Regulation; Ubiquitin; Up-Regulation; Vision; adeno-associated viral vector; age related; alkalinity; coral; diabetic; diabetic rat; dopaminergic neuron; gene therapy; glial cell-line derived neurotrophic factor; glutathione peroxidase; in vivo; innovation; knock-down; mitochondrial dysfunction; neuron loss; neurotrophic factor; novel; overexpression; parkin gene/protein; parkin protein; prevent; promoter; recruit; retinal neuron; therapeutic gene; tool; transcription factor; type I diabetic; ubiquitin-protein ligase

1. Scientific Abstract: The retinal being a part of the central nervous system is made up of fully differentiated and non-dividing cells - such as neurons, Muller cells (MC) and pigmented epithelium (RPE) – which may not be renewed if death occurs. Retinal cells consume large amounts of glucose and oxygen to generate ATP in mitochondria for their visual function. During ATP production via the mitochondrial electron transport chain (ETC), electrons leak which is captured by molecular oxygen producing reactive oxygen species (ROS) that damage mitochondrial membrane, proteins and DNA. Therefore, removal of damaged mitochondria via lysosomal degradation by mitophagy, a specific process of autophagy, and synthesis of new mitochondria (mitogenesis) are needed for mitochondrial homeostasis. We have published that thioredoxin-interacting protein (TXNIP) mediates cellular oxidative stress and mitophagic flux in retinal MC under high glucose conditions in vitro and in vivo in diabetic retinas. Furthermore, retinal neurons may undergo cell death by ferroptosis, a newly identified non-apoptotic mechanism of cell demise due to membrane lipid peroxidation by inhibition of glutathione peroxidase 4 (GPX4) and iron accumulation. Cell death by ferroptosis in diabetic retinopathy (DR) is still unknown. We hypothesize that the TXNIP-PARKIN-TFEB pathway is critical for mitophagy and biogenesis of mitochondrion and lysosome in retinal cells in DR. Parkin is an E3 ubiquitin ligase, which is recruited to damaged mitochondria by Pink1 (a mitochondrial protein kinase) for tagging ubiquitin for degradation by mitophagy. Parkin also promotes mitogenesis via ubiquitin-mediated degradation of PARIS (Parkin Interacting Substrate), which blocks PGC1α nuclear translocation, a critical step in mitogenesis. Similarly, Transcription factor EB (TFEB) is a lysosome- associated protein that mediates lysosomal biogenesis, mitogenesis (via PGC1α transcriptional activation) and expression of autophagy-related genes (ATGs) via a CLEAR gene network (CLEAR - Coordinated Lysosomal Expression And Regulation). We will investigate our hypothesis in 3 specific aims that: (i) Parkin is required for mitophagy and mitogenesis in DR; (ii) TFEB is critical for lysosome biogenesis and mitogenesis in DR; and (iii) TXNIP promoter-mediated gene therapy prevents early retinal abnormalities in DR. The proposal is significant in that the study targets the mitophagy-lysosome axis dysregulation in stress, a common feature of age-related chronic neurodegenerative diseases including DR. The role of Parkin and TFEB in mitochondrial quality control in DR has not been addressed before. The proposed gene therapy approach is innovative because the TXNIP promoter linked therapeutic gene (an anti-oxidant gene or a neurotrophic factor) with be induced under high glucose environment, such as seen in diabetes, while mostly unresponsive under physiological glucose levels.

1.科学摘要： 视网膜是中枢神经系统的一部分，由完全分化和非分裂的细胞组成， 例如神经元、米勒细胞（MC）和色素上皮（RPE）-如果死亡，它们可能不会更新。 发生。视网膜细胞消耗大量的葡萄糖和氧气，在线粒体中产生ATP， 视觉功能在通过线粒体电子传递链（ETC）产生ATP的过程中， 它被分子氧捕获，产生破坏线粒体的活性氧（ROS） 膜蛋白和DNA因此，通过溶酶体降解去除受损的线粒体， 线粒体自噬，一种特殊的自噬过程，和新线粒体的合成（有丝分裂）是需要的， 线粒体内稳态我们已经发表了硫氧还蛋白相互作用蛋白（TXNIP）介导的细胞凋亡， 糖尿病视网膜MC在高糖条件下的氧化应激和线粒体吞噬流量 视网膜此外，视网膜神经元可能会经历细胞死亡的铁凋亡，一个新发现的非凋亡 通过抑制谷胱甘肽过氧化物酶4（GPX 4）引起的膜脂质过氧化导致细胞死亡的机制 铁的积累。糖尿病视网膜病变（DR）中由铁凋亡引起的细胞死亡仍不清楚。我们假设 TXNIP-PARKIN-TFEB通路对线粒体自噬和线粒体及溶酶体的生物发生至关重要 Parkin是一种E3泛素连接酶，它被Pink 1（a 线粒体蛋白激酶）用于标记泛素以通过线粒体自噬降解。帕金还促进了 通过泛素介导的巴黎（帕金相互作用底物）降解的有丝分裂，PARIS可阻断PGC 1 α 核转位，有丝分裂的关键步骤。类似地，转录因子EB（TFEB）是一种溶酶体- 介导溶酶体生物发生、有丝分裂（通过PGC 1 α转录激活）和 通过CLEAR基因网络（CLEAR -协调溶酶体）表达自噬相关基因（ATG） 表达和调节）。我们将研究我们的假设在3个具体目标，即：（一）帕金是必要的， （ii）TFEB对于DR中的溶酶体生物发生和有丝分裂发生至关重要;以及（iii） TXNIP启动子介导的基因治疗可预防DR的早期视网膜异常。 因为这项研究的目标是应激中线粒体-溶酶体轴的失调，这是与年龄相关的一个共同特征。 慢性神经退行性疾病，包括DR。帕金和TFEB在线粒体质量控制中的作用 在DR中，以前没有提到过。所提出的基因治疗方法是创新的，因为TXNIP 启动子连接的治疗基因（抗氧化基因或神经营养因子）在高浓度下被诱导 葡萄糖环境，如糖尿病中所见，而在生理葡萄糖水平下大多无反应。