Role of RBC NO and ATP in Sickle Vasculopathy

红细胞 NO 和 ATP 在镰状血管病中的作用

基本信息

批准号：
8238249
负责人：
TIMOTHY J MCMAHON
金额：
$ 39.25万
依托单位：
DUKE UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2012
资助国家：
美国
起止时间：
2012-01-01 至 2015-12-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8238249
关键词：
Abnormal Red Blood Cell Acute Adhesions Adhesives Adverse effects Affect Anti-Inflammatory Agents Anti-inflammatory Binding Biological Models Biology Blood Cells Blood Transfusion Blood Vessels Blood flow Cell Adhesion Cell Communication Cell-Cell Adhesion Cells Cellular biology Chronic Complex Data Development Disease Endothelium Erythrocytes Event Failure Functional disorder Gases Goals Hypoxia In Vitro Individual Inflammation Inflammatory Knowledge Lead Leukocytes Life Lung Maintenance Measurable Mediating Membrane Modality Morbidity - disease rate Mus Nitric Oxide Normal tissue morphology Organ Pain Pathology Perfusion Phenotype Physiology Procedures Publishing Pulmonology Receptor Signaling Regulation Reporting Research Research Personnel Respiratory physiology Role S-Nitrosothiols Sickle Cell Sickle Cell Anemia Sickle Hemoglobin Signal Pathway Signal Transduction Testing Therapeutic Tissues Transfusion Vascular Diseases Vasodilation Work adhesion receptor base hemodynamics improved in vivo innovation leukocyte activation meetings mortality mouse model novel therapeutic intervention prevent response restoration sensor sickling vasoconstriction

项目摘要

DESCRIPTION (provided by applicant): Vasoconstriction, blood cell adhesion, and inflammation are each potentially devastating events in sickle cell disease (SCD). Sickle red cells (SS RBCs) demonstrate complex membrane and biologic abnormalities. Nitric oxide (NO) delivered by RBCs is both critical in the maintenance of vasodilation and a potent anti-inflammatory agent. ATP is also released by RBCs and signals increases in blood flow to meet O2 demand, typically by enhancing NO synthesis. While normal (AA) RBCs act as a hypoxia sensor by releasing both ATP and bioactive nitric oxide (NO), leading to NO-dependent vasodilation, SS RBCs are deficient in both content and ability to release both NO and ATP. The ability of SS RBCs to adhere to the endothelium and to activate leukocytes as well as other cells, along with their failure to induce pulmonary vasodilation, may result in part from their deficiencies in membrane-bound bioactive S-nitrosothiol (SNO) and ATP. Our preliminary data show that loading SS RBCs with NO/SNO down-regulates SS RBC adhesion, S RBC-stimulated leukocyte adhesion, and vaso-occlusion in vivo and modulates the vasoconstrictive pulmonary phenotype. Inhibition of ATP release by RBCs also induces RBC adhesion and pulmonary vasoconstriction. In SCD, abnormal vascular tone, cell adhesion, leukocyte activation, and inflammation are all believed to contribute to the pathophysiology of vaso-occlusion, which is central to both painful crises and acute and chronic organ damage. Thus, our central hypothesis is that NO and ATP deficits in SS RBCs directly contribute to both SS RBC adhesion, S RBC-induced activation of leukocytes, and pulmonary vasoconstriction. We further postulate that restoration of NO and ATP content in either SS or transfused (stored) AA RBCs will also improve some of the measurable adverse effects of SS RBCs in the lung. To test our hypothesis and progress toward achieving improved therapies for SCD, we have combined the efforts of investigators with expertise in SS RBC biology, transfusion medicine, and pulmonary physiology in order to 1) Determine the influence of NO/SNO- and ATP-repletion on pulmonary hemodynamics and gas exchange in isolated lungs and intact mice transfused with SS RBCs alone or in combination with strategies that modulate RBC adhesive events; 2) Test whether NO and ATP repletion of SS RBCs or stored AA RBCs can relieve vaso-occlusion in a mouse model in vivo; and 3) Determine the effect of SS RBC NO and ATP on the activation of RBC adhesion receptors in vitro, the signaling pathways involved, and RBC activation of leukocytes. Our long-term goal is to improve vascular tone, cell adhesion, and cell activation in SCD by identifying remediable SS RBC abnormalities and thereby reduce vaso-occlusion. This work will allow development of new therapeutic approaches to prevent and control vaso-occlusion and tissue damage in SCD. PUBLIC HEALTH RELEVANCE: Relevance Sickle cell disease (SCD) affects approximately 100,000 individuals in the USA and several million worldwide. Development of new therapies to treat or prevent vaso-occlusion, inflammation and abnormal lung function in SCD is critical to reducing the disease's morbidity and mortality. We propose to test the hypothesis, supported by our preliminary data, that the nitric oxide and ATP deficiencies of sickle red blood cells contribute to the abnormal red cell adhesion, cell-cell interactions, inflammatory leukocyte activation, vaso-occlusion, and adverse pulmonary hemodynamic changes caused by sickle red cells in a variety of model systems.

描述（由申请人提供）：血管收缩、血细胞粘附和炎症都是镰状细胞病（SCD）中潜在的破坏性事件。镰状红细胞 (SS RBC) 表现出复杂的膜和生物学异常。红细胞输送的一氧化氮 (NO) 对于维持血管舒张至关重要，也是一种有效的抗炎剂。红细胞也会释放 ATP，并发出信号增加血流量以满足 O2 需求，通常是通过增强 NO 合成来实现。正常 (AA) 红细胞通过释放 ATP 和生物活性一氧化氮 (NO) 充当缺氧传感器，导致 NO 依赖性血管舒张，而 SS 红细胞则缺乏释放 NO 和 ATP 的含量和能力。 SS 红细胞粘附内皮并激活白细胞和其他细胞的能力，以及它们不能诱导肺血管舒张的能力，部分可能是由于它们缺乏膜结合的生物活性 S-亚硝基硫醇 (SNO) 和 ATP。我们的初步数据表明，用 NO/SNO 负载 SS RBC 会下调 SS RBC 粘附、S RBC 刺激的白细胞粘附和体内血管闭塞，并调节血管收缩的肺表型。红细胞释放 ATP 的抑制也会诱导红细胞粘附和肺血管收缩。在 SCD 中，异常的血管张力、细胞粘附、白细胞活化和炎症都被认为与血管闭塞的病理生理学有关，而血管闭塞是痛苦危机以及急性和慢性器官损伤的核心。因此，我们的中心假设是，SS RBC 中的 NO 和 ATP 缺乏直接导致 SS RBC 粘附、S RBC 诱导的白细胞活化和肺血管收缩。我们进一步假设，恢复 SS 或输注（储存）AA 红细胞中的 NO 和 ATP 含量也将改善 SS 红细胞在肺部的一些可测量的不利影响。为了检验我们的假设和改进 SCD 疗法的进展，我们结合了具有 SS RBC 生物学、输血医学和肺生理学专业知识的研究人员的努力，以便 1) 确定 NO/SNO 和 ATP 补充的影响对单独输注 SS RBC 或与调节 RBC 粘附事件的策略相结合的离体肺和完整小鼠的肺血流动力学和气体交换的影响； 2）测试SS红细胞或储存的AA红细胞补充NO和ATP是否可以缓解体内小鼠模型的血管闭塞； 3)确定SS RBC NO和ATP对体外RBC粘附受体激活、所涉及的信号通路以及白细胞RBC激活的影响。我们的长期目标是通过识别可补救的 SS RBC 异常来改善 SCD 中的血管张力、细胞粘附和细胞活化，从而减少血管闭塞。这项工作将有助于开发新的治疗方法来预防和控制 SCD 中的血管闭塞和组织损伤。公共卫生相关性：相关性镰状细胞病 (SCD) 影响美国约 100,000 人，全球数百万人。开发治疗或预防 SCD 中血管闭塞、炎症和肺功能异常的新疗法对于降低该疾病的发病率和死亡率至关重要。我们建议测试由我们的初步数据支持的假设，即镰状红细胞的一氧化氮和 ATP 缺乏导致红细胞粘附异常、细胞间相互作用、炎症白细胞活化、血管闭塞和不良肺血流动力学各种模型系统中镰状红细胞引起的变化。