Non-invasive mitochondrial modulation therapy for ischemic stroke

摘要： 在美国，缺血性中风是导致死亡和长期残疾的主要原因。目前的黄金 局灶性脑缺血再灌注损伤的治疗标准为 血管再通恢复血流量。然而，很大一部分损失 由缺血/再灌流引起的，发生在再灌注期：由于缺血组织 复氧后的活性氧物种(ROS)迅速生成，在回流过程中很早就开始了。 再灌注损伤被证明很难用药物治疗，可能是因为有效的药物 在再灌流的早期阶段，血药浓度还不够高。 线粒体电子传递链(ETC)是细胞内ROS产生的主要部位 ETC过度激活引起的应激，导致线粒体膜电位(∆Ψm)升高； 这反过来会引发过量的ROS产生。我们认为，理想的治疗方法应该是以 ETC是无创的，以防止ROS的产生。因此， 我们在这项应用中的总体目标是开发一种新的、非侵入性的治疗方法，以使 复流期间线粒体过度活跃。我们将利用光感受器 近红外光(NIR)调制细胞色素C氧化酶(COX)的性质 线粒体活性，从而减弱ROS的产生，从而限制 脑缺血/再灌注损伤。细胞色素C氧化酶是主要的细胞光- NIR的受体和ETC的末端酶。我们发现了特定的近红外光谱 部分抑制COX的波长(而不是激活COX，即当前的范例)。 我们表明，在再灌流时应用抑制性近红外光谱，可提供 神经保护。在这项提案中，我们将以这些令人信服的初步数据为基础， 充分利用我们研究团队独特的多学科专业知识，以： ·询问缺血/再灌注损伤和近红外治疗的分子基础 (目标1)。 ·揭示中风后近红外治疗的机制(目标2) ·开发最佳利用近红外疗法治疗缺血性中风(目标3)。

Summary: Ischemic stroke is a leading cause of death and long-term disability in the US. The current gold standard for the treatment of ischemia-reperfusion injury in the setting of focal brain ischemia is restoration of blood flow with recanalization. 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 (∆Ψm), which in turn trigger excessive ROS production. We 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 near infrared light (NIR) 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 NIR and the terminal enzyme of the ETC. We have discovered specific NIR wavelengths that partially inhibit COX (instead of activating COX, i.e., the current paradigm). We show that inhibitory NIR, 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: • Interrogate the molecular underpinnings of ischemia/reperfusion injury and of NIR therapy (Aim 1). • Uncover the mechanisms of NIR therapy following stroke (Aim 2) • Develop the optimal use of NIR therapy as a treatment for ischemic stroke (Aim 3).