Targeting Cholesterol Homeostasis to maintain vision in MS-like optic neuritis

针对多发性硬化症样视神经炎的胆固醇稳态以维持视力

• 批准号: 10657163
• 负责人: Oliver W Gramlich
• 金额: $ 31.5万
• 依托单位: UNIVERSITY OF IOWA
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-08-01 至 2028-03-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10657163
• 关键词: 3-Dimensional; ATP binding cassette transporter 1; Acids; Acute; Affect; Agonist; Animal Experimentation; Animal Model; Animals; Aspirin; Autoimmune; Autopsy; Axon; Biological Assay; Blindness; Brain; Carrier Proteins; Cell Line; Cell Survival; Cells; Central Nervous System; Cholesterol; Cholesterol Homeostasis; Data; Demyelinating Diseases; Demyelinations; Development; Disease; Disease Progression; Dyes; Electroretinography; Event; Experimental Autoimmune Encephalomyelitis; Exposure to; Eye; Feedback; Future; Goals; Harvest; Healthcare Systems; Human; Immunohistochemistry; Impairment; In Vitro; Infiltration; Inflammation; Inflammatory; Injury; Interferon Type II; Investigation; Lysophosphatidylcholines; Mediating; Modeling; Molecular; Molecular Biology; Multiple Sclerosis; Mus; Myelin; Nerve Tissue; Neurons; Oligodendroglia; Ophthalmology; Optic Nerve; Optic Neuritis; Optical Coherence Tomography; Organoids; Outcome; Outcome Measure; Pathology; Pathway interactions; Patients; Pattern; Prevalence; Process; Recovery; Recovery of Function; Recycling; Reporter; Resources; Retina; Retinal Ganglion Cells; Role; Sterols; Synaptic plasticity; System; Systems Biology; TNF gene; Testing; Therapeutic; Therapeutic Studies; Time; Tissues; Vision; Visual evoked cortical potential; Visual impairment; cell type; central nervous system demyelinating disorder; experience; experimental study; functional disability; improved; in vivo; in vivo Model; induced pluripotent stem cell; inhibitor; innovation; insight; mevalonate; multiple sclerosis patient; myelination; neuronal survival; neuroprotection; novel therapeutics; preservation; prevent; regenerative; remyelination; repaired; response; restoration; retinal ganglion cell degeneration; retinogeniculate; reverse cholesterol transport; single-cell RNA sequencing; social; success; synaptogenesis; targeted treatment; transcriptome sequencing; translational study; uptake

Project Summary/Abstract: Acute optic neuritis (ON) is often the initial presenting manifestation of autoimmune demyelinating disorders such as Multiple Sclerosis (MS). Good recovery of vision after ON is common, but a considerable number of MS patients experience poor outcomes with severe visual impairment and permanent blindness as disease progresses. The increasing prevalence of MS will cause an immense social and financial challenge for health care systems and more studies are needed to improve treatment success in these diseases. Impaired recycling of cholesterol-rich myelin debris and decreased de novo synthesis of cholesterol have been identified as key limiting factors of recovery in demyelinating animal models. We have demonstrated decreased expression of the main cholesterol efflux transporter1, Abca1, and altered cholesterol homeostasis in the retinogeniculate system of animals with Experimental Autoimmune Encephalomyelitis (EAE)-ON. However, the exact mechanism by which changes in Abca1 expression affect cholesterol recycling remain elusive. We hypothesize that this impairment in cholesterol synthesis and transport significantly affects RGC survival, integrity of synaptic plasticity and remyelination and that restoration of cholesterol homeostasis via Abca1 regulatory feedback ameliorates visual impairment. In specific aim 1, we will determine the regulatory influence of ABCA1 expression on sterol synthesis and synaptic plasticity, cholesterol transport, and myelination in vitro. Eye and brain organoids from healthy subjects and MS patients will be exposed to Abca1 inhibitors, TNFα/IFNγ, or the demyelinating agent Lysolecithin. Effects of rescued Abca1 expression on sterol synthesis, cholesterol uptake and transport, synaptogenesis and myelination will be examined using single-cell RNA-sequencing, immunohistochemistry, and cholesterol efflux assays. In specific aim 2, we will determine the molecular, functional, and structural impact of Abca1 expression changes in the retinogeniculate pathway of EAE-ON and MS. EAE-ON will be induced in mice and effects of Abca1 expression changes will be determined using optokinetic response, optical coherence tomography, pattern electroretinography, and visual evoked potentials, followed by postmortem molecular and histopathologic analysis. Also, disruption in cholesterol homeostasis will be determined in MS donor eye tissue. Our proposed experiments will significantly advance the understanding of the role of cholesterol homeostasis in MS-like ON and provide an invaluable resource for future translational and therapeutic studies.

项目概要/摘要： 急性视神经炎（ON）通常是自身免疫性疾病的最初表现， 脱髓鞘疾病如多发性硬化症（MS）。ON后视力恢复良好是常见的， 但相当多的MS患者经历了严重视力损害的不良结局， 并随着疾病的发展而永久失明。多发性硬化症患病率的增加将导致 卫生保健系统面临巨大社会和财政挑战，需要进行更多的研究， 提高这些疾病的治疗成功率。 富含胆固醇的髓鞘碎片的再循环受损， 胆固醇已被确定为脱髓鞘动物模型中恢复的关键限制因素。我们 已经证实了主要胆固醇流出转运蛋白1 Abca 1的表达降低， 实验性高胆固醇血症动物视网膜神经系统胆固醇稳态改变 自身免疫性脑脊髓炎（EAE）-ON。然而，Abca 1 表达影响胆固醇再循环仍然难以捉摸。我们假设这种损伤 胆固醇的合成和转运显著影响RGC的存活、突触可塑性的完整性和 通过Abca 1调节反馈实现髓鞘再生和胆固醇稳态恢复 改善视力障碍。 在具体目标1中，我们将确定ABCA 1表达对甾醇的调节影响， 合成和突触可塑性、胆固醇转运和体外髓鞘形成。眼睛和大脑 健康受试者和MS患者的类器官将暴露于Abca 1抑制剂、TNFα/IFNγ或 脱髓鞘剂溶血素拯救的Abca 1表达对甾醇合成的影响， 胆固醇的摄取和转运、突触发生和髓鞘形成将使用单细胞 RNA测序、免疫组织化学和胆固醇流出试验。具体目标2： 确定Abca 1表达变化在分子、功能和结构上的影响， EAE-ON和MS的视网膜神经原细胞途径。EAE-ON将在小鼠中诱导，Abca 1 将使用视动反应，光学相干断层扫描， 图形视网膜电图和视觉诱发电位，然后进行死后分子和 组织病理学分析。此外，将在MS供体中确定胆固醇稳态的破坏。 眼组织 我们提出的实验将大大推进对胆固醇作用的理解， 并为未来转化和治疗提供了宝贵资源 问题研究