Role of Arginase 1 in Retinal Ischemia-Reperfusion Injury

精氨酸酶 1 在视网膜缺血再灌注损伤中的作用

• 批准号: 10522059
• 负责人: Abdelrahman Fouda
• 金额: $ 24.9万
• 依托单位: UNIV OF ARKANSAS FOR MED SCIS
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-09-01 至 2025-01-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10522059
• 关键词: ARG2 gene; Abbreviations; Academia; Anabolism; Arginine; Award; Bioenergetics; Blindness; Blood Vessels; Career Mobility; Cells; Cessation of life; Chronic; Clinical; Data; Diabetic Retinopathy; Disease; Enzymes; Flow Cytometry; Functional disorder; Genetic Transcription; Glaucoma; Goals; Grant; HDAC3 gene; Histone Deacetylase; Immune; In Vitro; Infiltration; Inflammation; Inflammatory; Inflammatory Response; Injury; Institution; Interleukin-1 beta; Investigational Drugs; Ischemia; Knockout Mice; Knowledge; Laboratories; Laboratory Finding; Mass Spectrum Analysis; Mediating; Mediator of activation protein; Mentors; Metabolic; Metabolism; Mission; Mitochondria; Mus; Myelogenous; Myeloid Cells; NOS2A gene; Nerve Degeneration; Neuronal Injury; Nitric Oxide; Nitric Oxide Synthase; Ornithine; Ornithine Decarboxylase; Outcome; Oxidative Stress; Paper; Pathologic Processes; Pathology; Pathway interactions; Pattern; Phase; Phenotype; Polyamines; Production; Protein Isoforms; Publishing; Putrescine; Recombinants; Reperfusion Injury; Reperfusion Therapy; Research; Research Personnel; Research Support; Retina; Retinal Diseases; Retinopathy of Prematurity; Role; Science; Secure; Signal Transduction; Stress; Supervision; TNF gene; Testing; Therapeutic; Training; Translating; Translational Research; Up-Regulation; Urea; Vascular Diseases; Vision Disorders; Vision research; arginase; arm; career; career development; chromatin modification; diabetic; effective therapy; factor A; in vivo; inhibitor; ischemic injury; knock-down; macrophage; neurovascular; neurovascular injury; new therapeutic target; novel; novel therapeutics; programs; protective effect; repair function; research study; retinal ischemia; retinal neuron; skill acquisition; urea cycle; vascular injury; vein occlusion; vision science

PROJECT SUMMARY Retinal ischemia is a major cause of vision loss in common retinal disease conditions including diabetic retinopathy, glaucoma, retinopathy of prematurity, and vein occlusion. This project aims to define the mechanisms of retinal ischemic injury and identify new therapeutic targets. My long-term career goal is to pursue a distinguished career in vision research and academia. I will achieve this through establishing a strong independent research program in an academic institution that promotes interdisciplinary biomedical science and translational research. My short-term goal is to attain intensive training and supervised career development skills that are required for my career transition to become an independent investigator. Securing this award will provide me with the necessary training to achieve my short- term goals and will be the first step towards independence and achieving my long-term goals. My mentor's lab has demonstrated the involvement of the arginase enzyme in retinal neurovascular diseases. Arginase has two isoforms. Building upon the lab's finding that the mitochondrial isoform, arginase 2 (A2), has a deleterious role in retinal ischemia-reperfusion (IR) injury, I developed a project focusing on the neurovascular protective role of the cytosolic isoform arginase 1 (A1). My recently published paper shows a neuroprotective role of A1 expression in myeloid cells. Arginase competes with nitric oxide synthase (NOS) for their common substrate L-arginine. Nitric oxide (NO) produced by inducible NOS (iNOS) causes neurovascular degeneration. I predict that A1 upregulation in myeloid cells limits iNOS-derived nitrative and oxidative stress and reduces inflammation through its downstream metabolites ornithine and putrescine. Putrescine is the precursor of polyamines and it is formed from ornithine by ornithine decarboxylase (ODC, the rate-limiting enzyme in polyamine biosynthesis). These metabolites have been shown to promote reparative myeloid cells through chromatin modification. In line with this, my preliminary data show that histone deacetylase (HDAC) 3 is increased in the absence of A1 in both IR-injured retinas and stimulated macrophages. HDAC3 is essential for macrophage inflammatory gene transcription and it has been shown to suppress A1 expression. Herein, I propose a novel suppressive effect of A1 on HDAC3. My central hypothesis predicts that myeloid A1 protects against retinal IR injury through ODC-mediated suppression of HDAC3. I will be using mice with myeloid-specific deletion of A1, ODC and HDAC3, as well as the investigational drug, BCT-100 (a PEGylated form of arginase 1), together with primary macrophages isolation and treatment with inhibitors for HDAC3 or arginase downstream enzyme, ODC. My goal is to achieve the following objectives: A) Determine the effect of manipulating the arginase pathway on myeloid cells infiltration / activation in retinal IR injury and the therapeutic potential of BCT- 100. B) Describe the cross talk between the arginase pathway and HDAC3 and determine whether A1 in myeloid cells mediates its protective effect through suppression of HDAC3.

项目总结 视网膜缺血是包括糖尿病在内的常见视网膜疾病导致视力丧失的主要原因 视网膜病变、青光眼、早产儿视网膜病变和静脉阻塞。该项目旨在定义 视网膜缺血性损伤的机制和寻找新的治疗靶点。 我的长期职业目标是在视觉研究和学术界追求卓越的职业生涯。这就做 通过在学术机构中建立强大的独立研究计划来实现这一点 促进跨学科生物医学科学和转化研究。我的短期目标是达到集约化 培训和监督职业发展技能，这些技能是我的职业过渡成为 独立调查员。获得这一奖项将为我提供必要的培训，以实现我的短期- 这是我实现长期目标的第一步，也是我实现长期目标的第一步。 我导师的实验室证明了精氨酸酶参与视网膜神经血管 疾病。精氨酸酶有两种亚型。根据实验室的发现，线粒体亚型精氨酸酶2 (A2)，在视网膜缺血-再灌注(IR)损伤中具有有害作用，我开发了一个项目，重点是 胞浆异构体精氨酸酶1(A1)的神经血管保护作用。我最近发表的论文显示了一个 髓系细胞A1表达的神经保护作用。精氨酸酶与一氧化氮合酶(NOS)竞争 它们的共同底物L-精氨酸。诱导型一氧化氮合酶(INOS)产生的一氧化氮(NO)引起神经血管病变 退化。我预测，髓系细胞中A1的上调限制了iNOS衍生的硝化和氧化应激 并通过其下游代谢物鸟氨酸和腐胺减少炎症。腐胺是 多胺的前体，由鸟氨酸通过鸟氨酸脱羧酶(ODC，限速酶)形成 多胺生物合成中的酶)。这些代谢物已被证明能促进修复性髓系细胞。 通过染色质修饰。与此相一致，我的初步数据显示组蛋白脱乙酰酶(HDAC)3是 在没有A1的情况下，IR损伤的视网膜和受刺激的巨噬细胞都增加了。HDAC3对以下各项至关重要 巨噬细胞炎症基因转录和它已被证明抑制A1的表达。在此，我 提出一种新的A1对HDAC3的抑制作用。我的中心假设是，髓系A1可以保护 通过ODC介导的HDAC3抑制抗视网膜IR损伤。我将使用具有髓系特异性的小鼠 A1、ODC和HDAC3以及研究药物BCT-100(精氨酸酶的一种聚乙二醇化形式)的缺失 1)，以及原代巨噬细胞的分离和下游HDAC3或精氨酸酶抑制剂的处理 酵素，ODC。我的目标是实现以下目标：a)确定操纵 精氨酸酶途径在视网膜IR损伤髓系细胞浸润/激活中的作用及BCT的治疗作用 100.B)描述精氨酸酶途径和HDAC3之间的串扰，并确定A1在髓系中 细胞通过抑制HDAC3介导其保护作用。