MITOCHONDRIAL MECHANISMS IN OPTIC NEUROPATHY

视神经病变的线粒体机制

• 批准号: 6518606
• 负责人: GINO A CORTOPASSI
• 金额: $ 25.97万
• 依托单位: UNIVERSITY OF CALIFORNIA AT DAVIS
• 依托单位国家: 美国
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-05-01 至 2004-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6518606
• 关键词: bioenergetics; cell differentiation; cell line; gene mutation; membrane potentials; mitochondrial DNA; mitochondrial disease /disorder; mitochondrial membrane; molecular cloning; molecular pathology; neurons; neurotoxins; optic nerve disorder

The broad, long-term objective of this project is to determine the pathophysiological mechanism of Leber's Hereditary Optic Neuropathy (LHON), in the hopes that a mechanistic understanding of this disease will lead to more effective therapy. LHON is the result of the inheritance of primary mutations of the mtDNA in three different subunits of Complex I of the mitochondrial respiratory chain. We have recently demonstrated that the most common LHON pathogenic mutation can be transferred into human Nt2 cells and are differentiable into neuron-like cells. We have also observed in earlier work that LHON cells appear to be activated for apoptosis. Thus there are six Specific Aims: 1) to construct all three LHON mutations in a cell environment differentiable into neurons, and measure the effects of differentiation, of respiratory substrates, and of induction of electron transport chain activity on viability in the neuronal environment; 2) to measure the bioenergetic effects of differentiation into a neuronal environment in cells and mitochondria, by mitochondrial membrane potential, oxygen consumption, and reduction of Alamar blue; 3) To measure the apoptotic activity of Nt2 cells and neurons bearing the LHON mutations, and to determine if a particular step in this pathway is activated in LHON cells; 4) to determine if neuron-specific excitotoxic mechanisms are activated in LHON neurons; 5) to determine if LHON mutations exert a concerted effect on gene expression, by array analysis of mRNA levels in mutant and control neurons, and 6) based on the results of Aims 1-5, to integrate and confirm the understanding of the LHON pathophysiological mechanism by rescue with mechanism-specific pharmacological agents, including bioenergetic supplements, anti- apoptotic agents, glutamate antagonists, antioxidants and chelators.

该项目的广泛、长期目标是确定莱伯遗传性视神经病（LHON）的病理生理机制，希望对这种疾病的机制了解能够带来更有效的治疗。 LHON 是线粒体呼吸链复合体 I 的三个不同亚基中 mtDNA 初级突变遗传的结果。 我们最近证明，最常见的 LHON 致病突变可以转移到人类 Nt2 细胞中，并可分化为神经元样细胞。 我们在早期的工作中还观察到 LHON 细胞似乎被激活以进行凋亡。 因此，有六个具体目标：1）在可分化为神经元的细胞环境中构建所有三种 LHON 突变，并测量分化、呼吸底物和电子传递链活性诱导对神经元环境中活力的影响； 2) 通过线粒体膜电位、耗氧量和阿拉玛蓝的还原来测量细胞和线粒体分化成神经元环境的生物能效应； 3) 测量带有LHON突变的Nt2细胞和神经元的凋亡活性，并确定该途径中的特定步骤是否在LHON细胞中被激活； 4) 确定LHON神经元中神经元特异性兴奋毒性机制是否被激活； 5) 通过对突变体和对照神经元的 mRNA 水平进行阵列分析，确定 LHON 突变是否对基因表达产生协同影响，以及 6) 基于目标 1-5 的结果，整合并确认对 LHON 病理生理学的理解通过使用机制特异性药物来挽救机制，包括生物能量补充剂、抗凋亡剂、谷氨酸拮抗剂、抗氧化剂和螯合剂。