Mitochondrial pyruvate transport in retinal health and disease

线粒体丙酮酸转运在视网膜健康和疾病中的作用

• 批准号: 10320069
• 负责人: Jianhai Du
• 金额: $ 39.62万
• 依托单位: WEST VIRGINIA UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-01-01 至 2024-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10320069
• 关键词: Age related macular degeneration; Aging; Aspartate; Biochemical; Cell Death; Cell Respiration; Cells; Choroid; Clinical; Complex; Data; Defect; Dependence; Disease; Ecosystem; Energy Metabolism; Foundations; Functional disorder; Glucose; Glutamates; Glutamine; Glycolysis; Goals; Health; Human body; Image; In Vitro; Individual; Infusion procedures; Ketone Bodies; Knock-out; Knockout Mice; Knowledge; Link; Macular degeneration; Mass Spectrum Analysis; Metabolic; Metabolism; Methodology; Mitochondria; Morphology; Muller' s cell; Neuroglia; Neurons; Neurotransmitters; Nutrient; Optical Coherence Tomography; Outcomes Research; Oxidative Phosphorylation; Oxides; Phenotype; Photoreceptors; Pyruvate; Resolution; Retina; Retinal Degeneration; Retinal Diseases; Retinal Pigments; Role; Structure of retinal pigment epithelium; Supporting Cell; Testing; Therapeutic; Tissues; Tracer; Transmission Electron Microscopy; Vascular blood supply; Vision; beta-Hydroxybutyrate; cell type; conditional knockout; glial activation; glucose transport; high resolution imaging; in vivo; inherited retinal degeneration; innovation; ketogenic diet; late-onset retinal degeneration; metabolomics; mitochondrial dysfunction; oxidation; preservation; pyruvate carrier; retinal rods; visual dysfunction

PROJECT SUMMARY/ABSTRACT The retina is the most metabolically active neuronal tissue in the human body. The defect in the energy metabolism of photoreceptor neurons and their supporting cells including glia and retinal pigment epithelium (RPE), emerges as an important underlying cause for retinal degenerative diseases such as inherited retinal degeneration and aging-related macular degeneration (AMD). Previous studies and data from our lab support that photoreceptors, glial cells, and RPE are biochemically adapted to form a metabolic ecosystem: 1) RPE transports glucose from choroid blood supply to photoreceptors; 2) Photoreceptors metabolize most of the glucose into lactate; 3) Lactate inhibits glycolysis in RPE to facilitate glucose transport; 4) Lactate stimulate Müller glia to synthesize glutamine for photoreceptors. The long term goal of this project is to define the metabolic interactions between photoreceptors and Müller glia and between RPE and outer retina in vivo and identify their roles in retinal function and degeneration. Mitochondrial pyruvate carrier (MPC) controls the entry of pyruvate from glycolysis into mitochondria for oxidative metabolism. We recently found that the deletion of MPC in the retina depletes glutamine and glutamate, inhibits glutamine utilization and enhancing ketone body oxidation, resulting in a progressive decline of visual function and retinal degeneration. Our preliminary data showed that the deletion of MPC in photoreceptors causes much milder phenotype than whole retina knockout, supporting the metabolic interaction that lactate is utilized by other cells. The objective of this proposal is to investigate the roles of mitochondrial pyruvate transport in photoreceptor, Müller cells and RPE in metabolic interactions, visual function, and retinal survival. We plan to conditionally knockout MPC in photoreceptors, glia or RPE separately and rigorously test our hypothesis using advanced tracer methodology, mass spectrometry, in vivo infusion with 13C tracers, high-resolution imaging of metabolites, visual function tests, optical coherence tomography, and transmission electron microscopy. The outcome of this research will establish a conceptual framework for retinal metabolism that describes how glucose is transported and utilized in different retinal cells and describes how disruption of metabolism in one kind of retinal cells impacts the metabolism, function, and viability of other retinal cells. This new knowledge will provide the basis for understanding the mechanisms of retinal degenerative diseases and lay the foundation for developing new treatments.

项目摘要/摘要 视网膜是人体中最活跃的神经元组织。在 光感受器神经元及其支持细胞（包括神经胶质和残留）的能量代谢 颜料上皮（RPE）是永久退化的重要根本原因 诸如遗传残留变性和与衰老有关的黄斑变性（AMD）等疾病。 先前的研究和来自我们实验室的数据支持感光细胞，神经胶质细胞和RPE是 生物化学适应形成代谢生态系统：1）RPE从脉络膜中运输葡萄糖 光感受器的血液供应； 2）光感受器将大部分葡萄糖代谢成鞋底； 3） 乳酸抑制RPE中的糖酵解，以促进葡萄糖转运。 4）乳酸刺激müller神经胶质 合成谷氨酰胺用于光感受器。该项目的长期目标是定义 光感受器与穆勒胶质的代谢相互作用以及RPE和外视网膜之间的相互作用 体内并确定其在残留功能和变性中的作用。 线粒体丙酮酸载体（MPC）控制丙酮酸从糖酵解进入进入 线粒体用于氧化代谢。我们最近发现，MPC在视网膜中删除 耗尽谷氨酰胺和谷氨酸，抑制谷氨酰胺的利用率并增强酮体 氧化，导致视觉功能和永久性变性的逐渐下降。我们的 初步数据表明，光感受器中MPC的删除会导致很多米勒 表型比整个视网膜淘汰赛，支持使用的代谢相互作用 由其他细胞。该建议的目的是研究线粒体丙酮酸的作用 在光感受器，müller细胞和RPE中的转运代谢相互作用，视觉功能和 视网膜生存。我们计划分别在光感受器，神经胶质或RPE中有条件地敲除MPC 并严格地使用高级示踪剂方法论质谱法测试我们的假设 带有13C示踪剂的体内输注，代谢物的高分辨率成像，视觉功能测试，光学 相干断层扫描和透射电子显微镜。 这项研究的结果将建立一个永久代谢的概念框架 描述如何在不同的视网膜细胞中运输和使用葡萄糖，并描述 一种视网膜细胞中代谢的破坏会影响新陈代谢，功能和生存力 其他永久性细胞。这些新知识将为理解 永久性退行性疾病的机制，为发展新的基础奠定了基础 治疗。