Limiting brain reperfusion injury by controlling mitochondrial function

通过控制线粒体功能限制脑再灌注损伤

• 批准号: 9149032
• 负责人: MAIK HUETTEMANN
• 金额: $ 33.67万
• 依托单位: WAYNE STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-09-30 至 2019-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9149032
• 关键词: Affect; Algorithms; Apoptosis; Area; Astrocytes; Attenuated; Blood flow; Brain; Brain Injuries; Brain Ischemia; Calcium; Cardiopulmonary Resuscitation; Cause of Death; Cell Death; Cellular Stress; Cerebrovascular Disorders; Cerebrum; Cessation of life; Data; Electron Transport; Enzymes; Event; Free Radical Formation; Free Radicals; Gel; Generations; Goals; Heart Arrest; Human; Hyperactive behavior; Image; In Vitro; Inflammation; Interruption; Ischemia; Lead; Light; Mammals; Mass Spectrum Analysis; Mediating; Membrane Potentials; Metabolic; Microglia; Mitochondria; Mitochondrial Proteins; Modeling; Morbidity - disease rate; Neurologic; Neurons; Oligodendroglia; Oxidases; Oxygen; Patient-Focused Outcomes; Pharmaceutical Preparations; Phase; Phosphorylation; Phototherapy; Process; Production; Property; Protein Dephosphorylation; Proton Pump; Rattus; Reactive Oxygen Species; Reperfusion Injury; Reperfusion Therapy; Research; Respiration; Resuscitation; Site; Stress; Testing; Therapeutic; Time; Tissues; cytochrome c oxidase; disability; in vivo; indexing; irradiation; mitochondrial membrane; mortality; natural hypothermia; neuroprotection; phosphoproteomics; prevent; public health relevance; restoration

 DESCRIPTION (provided by applicant): Cerebrovascular disease, most notably brain ischemia, is a leading cause of death and long-term disability in the US. The current and only treatment is prompt restoration of blood flow to the ischemic tissue. However, a substantial portion of the damage caused by ischemia/reperfusion occurs during the reperfusion phase: as ischemic tissue is reoxygenated reactive oxygen species (ROS) are quickly generated, starting early during reflow. Reperfusion injury has proved difficult to treat pharmacologically, likely because effective drug concentrations have not built up sufficiently during the early phase of reperfusion. The mitochondrial electron transport chain (ETC) is a major site of ROS production during cellular stress due to ETC hyper-activation, which causes high mitochondrial membrane potentials (ΔΨm), which in turn trigger excessive ROS production. We thus propose that the ideal therapy should target the ETC non-invasively to prevent the generation of ROS from the onset of reflow. Accordingly, our overall goal in this application is to develop a new, non-invasive therapy to normalize mitochondrial hyperactivity during reflow. We will capitalize on the photoreceptive properties of cytochrome c oxidase (COX) for infrared light (IRL) to modulate mitochondrial activity, thereby attenuating the production of ROS and, as a result, limit ischemia/reperfusion injury in the brain. Cytochrome c oxidase is the primary cellular photo-acceptor of IRL and the terminal enzyme of the ETC. We have discovered four specific IRL wavelengths that partially inhibit COX (instead of activating COX, i.e., the current paradigm). We show that inhibitory IRL, applied at the time of reperfusion, provides profound neuroprotection. In this proposal, we will build on these compelling preliminary data and capitalize on the unique, multi-disciplinary expertise of our research team to: Identify the combinations and energies of our four IRL wavelengths that yield optimal inhibition of COX and mitochondria in vitro using isolated rat brain COX and mitochondria (Aim 1). Investigate the mechanism of IRL-mediated protection in support of our central hypothesis of IRL action during reperfusion: IRL → COX activity↓ → ΔΨm↓ → ROS↓ → viability↑, using real-time imaging of mitochondrial funtion in rat primary neural cells exposed to simulated ischemia-reperfusion (Aim 2). Develop IRL-mediated protection and identify the optimal temporal treatment paradigm using a rat model for global brain ischemia to maximize post-ischemic neuroprotection (Aim 3).

 描述（由适用提供）：脑血管疾病，最著名的是脑缺血，是美国死亡和长期残疾的主要原因。电流和唯一的治疗方法是迅速恢复流向缺血组织的血液。然而，在再灌注阶段发生了由缺血/再灌注引起的很大一部分损害：由于缺血组织是重新氧的活性氧（ROS），因此很快就会产生，从回流期间早期开始。再灌注损伤已被证明很难在药理学上治疗，这可能是因为在再灌注早期阶段没有足够的药物浓度积累。线粒体电子传输链（ETC）是由于ETC高激活引起的细胞应激期间ROS产生的主要部位，这会导致高线粒体膜电位（Δψm），这反过来又触发了多余的ROS产生。因此，我们建议理想的疗法应无创地靶向ETC，以防止ROS产生回流的发作。根据该应用，是开发一种新的非侵入性疗法，以使反流期间的线粒体多动症正常化。我们将利用细胞色素C氧化酶（COX）的光感受感染特性来调节线粒体活性，从而减轻ROS的产生，并因此而限制大脑中的缺血/再灌注损伤。细胞色素C氧化酶是IRL和末端酶的主要细胞光受体。我们发现了四个特定的IRL波长，它们部分抑制了Cox（而不是激活Cox，即当前的范式）。我们表明，在再灌注时应用的抑制性IRL提供了深刻的神经保护作用。在这项建议中，我们将以这些引人注目的初步数据为基础，并利用我们研究团队的独特，多学科的专业知识，以确定四个IRL波长的组合和能量，这些IRL波长的组合和能量可以最佳地抑制Cox和Mitochondria在体外利用分离的大鼠Cox和Mitochochria（AIM 1）。研究IRL介导的保护的机理，以支持我们在再灌注过程中IRL作用的中心假设：IRL→COX活性↓→Δψm↓→ROS↓→ROS↓→可靠性↑，使用将大鼠主要神经球体中的线粒体函数实时成像暴露于模拟的ischemia-reperfusion（SIM 2）。开发IRL介导的保护，并使用全球脑缺血的大鼠模型确定最佳的临时治疗范式，以最大程度地提高缺血后神经保护作用（AIM 3）。