Oxidative stress in vaso-occlusion pathophysiology of sickle cell disease

镰状细胞病血管闭塞病理生理学中的氧化应激

基本信息

批准号：
9333429
负责人：
Melinda D Wu
金额：
$ 17.44万
依托单位：
OREGON HEALTH & SCIENCE UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2016
资助国家：
美国
起止时间：
2016-08-16 至 2021-07-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9333429
关键词：
ADAMTS Acute Address Adhesions Advisory Committees Animals Antioxidants Biochemical Blood Platelets Blood Vessels Blood Volume Blood flow Career Mobility Cell Adhesion Molecules Cells Chronic Clinical Research Clinical Trials Complex Contrast Media Crossover Design Data Disease Disease model Disintegrins Endothelial Cells Endothelium Enzymes Equilibrium Erythrocytes Event Exercise Foundations Functional disorder Gene-Modified Genetic Glutathione Reductase Goals Hematological Disease Hemoglobin Hemolysis Human Hypoxia Image Imaging Techniques Impairment In Situ Inflammation Inflammatory Injury Institution Kidney Knowledge Lead Limb structure Lipids Measurement Measures Mediating Mentorship Metalloproteases Microbubbles Microvascular Dysfunction Modeling Modification Molecular Mus Muscle Myocardium NADP NOS3 gene Nitric Oxide Organ Oxidases Oxidative Stress Oxygen P-Selectin Pain Patients Peptide Hydrolases Perfusion Peroxonitrite Pharmaceutical Preparations Pharmacology Phytochemical Placebos Plasma Platelet Activation Play Positron-Emission Tomography Process Production Proteins Pulmonary Vascular Resistance Reactive Oxygen Species Recombinants Recruitment Activity Reperfusion Injury Research Personnel Research Training Resources Rest Rheology Role Serum Markers Sickle Cell Anemia Site Skeletal Muscle Stress Techniques Testing Therapeutic Thrombosis Thrombospondins Tissues Training Programs Ultrasonography United States Vascular resistance Vasoconstrictor Agents Vasodilator Agents Xanthine Oxidase acetovanillone blood flow measurement cleavage factor contrast enhanced design disorder control glutathione peroxidase improved in vivo inhibitor/antagonist insight leukocyte activation liquid chromatography mass spectrometry metabolomics microPET molecular imaging mouse model multidisciplinary novel novel therapeutic intervention oxidation perfusion imaging polymerization pre-clinical prevent skills targeted treatment therapeutic target treatment effect treatment strategy vascular abnormality vasomotion von Willebrand Factor

项目摘要

PROJECT SUMMARY Sickle cell disease (SCD) is the most common genetic hematologic disorder in the United States. The pathophysiology of organ dysfunction in SCD extends beyond abnormal rheology and hemolysis, and includes abnormal vascular function, thrombosis, and inflammation. There is increasing evidence that oxidative stress is an important biochemical trigger for vaso-occlusion (VO) in SCD. Increased reactive oxygen species (ROS) can lead to VO through platelet and leukocyte activation, and microvascular dysfunction. Whether pharmacologic reduction in oxidative stress prevents VO and improves microvascular perfusion is not known. The goal of this proposal is to use state-of-the-art microvascular perfusion and molecular imaging techniques together with advanced plasma biochemical analysis to test mechanism and therapeutic impact of two promising anti-oxidants implicated in reducing ROS in SCD: (a) N-acetylcystine (NAC), and (b) apocynin. In Aim 1, the Townes murine model of SCD and control mice will be studied. Non-invasive microvascular perfusion imaging with contrast-enhanced ultrasound (CEU) of the kidney and skeletal muscle under normoxic and post-hypoxic conditions will be performed in mice pre-treated for 6 weeks with NAC, apocynin, or vehicle. Parametric perfusion analysis (microvascular blood volume and flux rate) and dispersion modeling will be used to better characterize the vascular events responsible for abnormal flow in the SCD model or treatment effect. In Aim 2, CEU molecular imaging of activated von Willebrand Factor (vWF) and platelets, and PET molecular imaging of oxidative stress will be used to further assess the microvascular molecular events responsible for abnormal perfusion or treatment effect from the NAC or apocynin. In both of these Aims, advanced LC-MS/MS for unbiased metabolomics and targeted identification of oxidative modification of VWF and its main regulatory protease (ADAMTS-13), as well as other key ROS, will be performed to evaluate drug effect. In Aim 3, CEU perfusion imaging of limb skeletal muscle, kidney, and myocardium will be performed in a pilot clinical trial testing the hypothesis that reducing oxidative stress with NAC improves microvascular perfusion in patients with SCD. This trial is designed as a double cross-over with NAC or placebo for 6 weeks each. The results of this proposal will address a critical gap in our knowledge of the pathobiology of SCD and provide insight into new therapeutic interventions. It will also provide the PI with a rich research training program (including multidisciplinary mentorship and advisory teams, comprehensive coursework, and career advancement resources available at the institution) that will lay the foundation to become an independent investigator who is able to use advanced imaging and other analytic techniques in pre-clinical and clinical studies to examine microvascular pathophysiology in hematologic disease.

项目概要镰状细胞病（SCD）是美国最常见的遗传性血液病。这 SCD 器官功能障碍的病理生理学超出了异常流变学和溶血的范围，还包括血管功能异常、血栓形成和炎症。越来越多的证据表明氧化应激是 SCD 中血管闭塞 (VO) 的重要生化触发因素。活性氧 (ROS) 增加可通过血小板和白细胞激活以及微血管功能障碍导致 VO。无论药物减少氧化应激可预防 VO 并改善微血管灌注尚不清楚。该提案的目标是使用最先进的微血管灌注和分子成像技术结合先进的血浆生化分析来测试两种药物的机制和治疗影响与减少 SCD 中的 ROS 相关的有前景的抗氧化剂：(a) N-乙酰胱氨酸 (NAC) 和 (b) 夹竹桃麻素。在目标 1，将研究 SCD 小鼠模型和对照小鼠。无创微血管常氧条件下肾脏和骨骼肌的超声造影 (CEU) 灌注成像和缺氧后条件将在用 NAC、夹竹桃麻素或媒介物预处理 6 周的小鼠中进行。将使用参数灌注分析（微血管血量和通量率）和弥散模型更好地表征导致 SCD 模型中血流异常或治疗效果的血管事件。在目标 2 中，活化血管性血友病因子 (vWF) 和血小板的 CEU 分子成像，以及 PET 分子成像氧化应激成像将用于进一步评估导致氧化应激的微血管分子事件 NAC 或罗布麻宁的灌注或治疗效果异常。在这两个目标中，先进的 LC-MS/MS 用于无偏代谢组学和 VWF 氧化修饰及其主要调控的靶向鉴定将进行蛋白酶 (ADAMTS-13) 以及其他关键 ROS 来评估药物效果。在目标 3 中，CEU 肢体骨骼肌、肾脏和心肌的灌注成像将在试点临床试验中进行检验用 NAC 减少氧化应激可改善患者微血管灌注的假设与SCD。该试验设计为与 NAC 或安慰剂的双交叉，各为期 6 周。结果该提案将弥补我们在 SCD 病理学知识方面的一个关键差距，并提供深入了解新的治疗干预措施。它还将为PI提供丰富的研究培训计划（包括多学科指导和咨询团队、综合课程和职业发展该机构可用的资源），这将为成为一名独立调查员奠定基础能够在临床前和临床研究中使用先进的成像和其他分析技术来检查血液疾病中的微血管病理生理学。