Oxidative stress mechanisms regulating gamma-globin gene transcription in sickle cell disease

镰状细胞病中调节伽马珠蛋白基因转录的氧化应激机制

• 批准号: 10340421
• 负责人: Rahima Zennadi
• 金额: $ 61.02万
• 依托单位: DUKE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-07-01 至 2026-06-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10340421
• 关键词: Address; Advanced Development; Affect; Anemia; Automobile Driving; Bone Marrow; Cessation of life; Chemicals; Chronic; Chronic stress; Clinical; DNA; DNA Methylation; DNA Modification Process; Data; Development; Dioxygenases; Electronic Medical Records and Genomics Network; Enzymes; Epigenetic Process; Erythroblasts; Erythrocytes; Erythroid; Erythropoiesis; Event; Extramedullary Hematopoiesis; FOXO3A gene; Fetal Hemoglobin; Foundations; Functional disorder; Gene Expression; Gene Expression Regulation; Gene Silencing; Genes; Genetic Transcription; Globin; Goals; Hemolysis; Hereditary Disease; Histone Acetylation; Histone Deacetylase; Hypoxia; In Vitro; Inherited; Intervention; Knock-out; Knowledge; MAPK3 gene; Mediating; Mediator of activation protein; Mendelian disorder; Messenger RNA; Morbidity - disease rate; Mus; Names; Organ; Oxidative Stress; Pain; Pathogenesis; Pathway interactions; Patients; Point Mutation; Production; Protein translocation; Reactive Oxygen Species; Regulation; Regulator Genes; Role; Severities; Sickle Cell; Sickle Cell Anemia; Sickle Hemoglobin; Splenomegaly; Stress; Survival Rate; Switch Genes; Symptoms; Untranslated RNA; Vascular Diseases; beta Globin; biological adaptation to stress; disease phenotype; effective therapy; epigenetic regulation; fetal reactivity; fetus cell; gamma Globin; gene induction; gene repression; hematopoietic tissue; histone modification; improved; in vivo; insight; mouse model; novel; oxidative damage; premature; prevent; progenitor; reduce symptoms; sickle erythroid; sickling; therapeutic target; transcription factor; vaso-occlusive crisis

Oxidative stress mechanisms regulating g-globin gene transcription in sickle cell disease Abstract: Sickle cell disease (SCD) is the most common inherited monogenic disorder affecting the β-globin gene, leading to the production of sickled-shaped red blood cells (RBCs). Patients with SCD suffer from severe anemia and painful vasoocclusive crises, which are both exacerbated by increased oxidative stress. Induction of normal, but developmentally silenced γ-globin gene of fetal hemoglobin (HbF) expression reduces RBC sickling-mediated vasoocclusion, and anemia, consequently ameliorating clinical severity of SCD. Reducing oxidative stress also improves SCD phenotypic severity. Yet effective treatment options remain limited. Understanding the pathogenesis of the erythroid mechanisms regulating oxidative stress and factors engaged in silencing γ-globin gene, is of substantial value to SCD patients. Our data uncovered an unanticipated role for mediators of oxidative stress in RBC sickling, and in regulating the transcriptional regulatory machinery that represses γ-globin genes as well as epigenetic enzyme components associated with γ-globin to β-globin gene switch in erythroid progenitors. Here, to extend our studies, we will in vitro and in vivo genetically and/or chemically manipulate these mediators of oxidative stress and the regulated pathways using a SCD mouse model, and determine their effects on γ-globin gene regulation, and thus sickling, and their mechanism of action on the transcriptional regulatory machinery that silences γ-globin gene during sickle RBC production. We will also determine the contribution of these mediators in epigenetic DNA and histone modifications associated with γ-globin to β-globin gene switch during sickle RBC production. Because stress erythropoiesis compensates for anemia caused by oxidative damage to the RBCs, we will further validate the effects of these mediators of oxidative stress on stress erythropoiesis in splenic hematopoietic tissue and examine their role in chronic erythroid stress-response, specifically in erythroid terminal maturation and enucleation. We strongly believe that our studies will provide novel and unprecedented insights into the exact mechanisms regulating γ-globin gene silencing and γ-globin to β-globin gene switch in SCD, as well as ineffective erythroid maturation and enucleation. Our long- term goal is to identify remediable sickle erythroid abnormalities to improve SCD pathophysiology. In addition, our studies will lay the foundation for more rational approaches to therapies that better alleviate SCD clinical symptoms.

镰状细胞病中调节g-珠蛋白基因转录的氧化应激机制 摘要： 镰状细胞病是最常见的影响β-珠蛋白的遗传性单基因疾病。 基因，导致镰状红细胞(RBCs)的产生。患有SCD的患者患有 严重的贫血和痛苦的血管闭塞危机，两者都会因氧化增加而加剧 压力。诱导正常但发育沉默的胎儿血红蛋白γ-珠蛋白基因(HBF) 表达减少RBC镰刀状介导的血管闭塞和贫血，从而改善 SCD的临床严重程度。减少氧化应激也可以改善SCD的表型严重程度。还没有 有效的治疗选择仍然有限。对红系疾病发病机制的认识 调控氧化应激的机制和参与沉默γ-珠蛋白基因的因素是实质性的 对SCD患者的价值。我们的数据揭示了氧化应激介质在脑内的一个意想不到的作用 在调节抑制γ-珠蛋白基因的转录调控机制中 红系γ-珠蛋白向β-珠蛋白基因转换相关的表观遗传酶组分 祖先。在这里，为了扩展我们的研究，我们将在体外和体内从基因和/或化学上 使用SCD小鼠模型操纵这些氧化应激介质和调节的途径， 并确定它们对γ-珠蛋白基因调控的影响，从而使其呈镰状，以及它们的作用机制 镰状红细胞沉默γ-珠蛋白基因在转录调控机制中的作用 制作。我们还将确定这些介体在表观遗传DNA和组蛋白中的作用。 与γ-珠蛋白相关的修饰 在镰状红细胞产生过程中β-珠蛋白基因的切换。因为 应激性红细胞生成补偿红细胞氧化损伤引起的贫血，我们将进一步 这些氧化应激介质对脾组织应激性红细胞生成的影响 并研究它们在慢性红系应激反应中的作用，特别是在 红系终末成熟和去核。我们坚信，我们的研究将提供新颖的 以及对调控γ-珠蛋白基因沉默和γ-珠蛋白的确切机制的前所未有的见解 β-珠蛋白基因在SCD中的切换，以及无效的红系成熟和去核。我们的长- 学期目标是确定可治疗的镰状红系异常，以改善SCD的病理生理学。在……里面 此外，我们的研究将为更合理的治疗方法奠定基础， 缓解SCD临床症状。