Inhibition of ferroptosis after intracerebral hemorrhage

抑制脑出血后铁死亡

基本信息

批准号：
9534292
负责人：
Jian Wang
金额：
$ 20.47万
依托单位：
JOHNS HOPKINS UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2018
资助国家：
美国
起止时间：
2018-07-01 至 2020-06-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9534292
关键词：
Affect Aging Anabolism Animals Antioxidants Apoptosis Attention Autophagocytosis Biliverdine Binding Proteins Bipyridyl Blood Brain Brain Injuries Brain hemorrhage Carbon Monoxide Cations Cell Death Cells Cerebral hemisphere hemorrhage Clinical Trials Coenzyme A Ligases Deferoxamine Dose Edema Electrons Exhibits Extracellular Space Family member Future Glutamates Glutathione Goals Heme Hemoglobin Hippocampus (Brain)Histologic Homologous Gene Human In Vitro Injections Injury Iron Iron Chelating Agents Ischemic Stroke Lesion Lip structure Lipid Peroxidation Lipids Magnetic Resonance Imaging Measures Membrane Lipids Metabolism Mitochondria Modeling Molecular Morbidity - disease rate Morphology Mus NADPH Oxidase Necrosis Nervous System Physiology Neurologic Deficit Neurologic Dysfunctions Neurological outcome Neurons Oligodendroglia Outcome Oxygenases PTGS2 gene Parkinson Disease Pathway interactions Patients Permeability Pilot Projects Production Reactive Oxygen Species Recovery Reporting Research Response Elements Secondary to Site Slice Stroke TFRC gene Testing Therapeutic Toxic effect Transgenic Mice Transmission Electron Microscopy Validation Work aged brain cell cancer cell cerebral atrophy clinically relevant collagenase cyclooxygenase 2 experimental study functional outcomes glutathione peroxidase improved inhibitor/antagonist insight lipid peroxidation inhibitor lipophilicity molecular marker mortality mouse model neuron loss neuronal survival novel novel therapeutics overexpression preclinical study preclinical trial prevent sex small molecule therapy development white matter injury

项目摘要

Inhibition of ferroptosis after intracerebral hemorrhage Spontaneous intracerebral hemorrhage (ICH) is the stroke subtype with the highest mortality and morbidity. Because large amounts of blood are released into the extracellular space during ICH, the metabolism of hemoglobin/free heme is very important for brain recovery. Heme is degraded by heme oxygenase into iron, biliverdin, and carbon monoxide. Importantly, iron accumulation within the brain contributes to secondary brain injury after ICH. Indeed, iron toxicity contributes to collagenase-induced hemorrhagic brain injury in mice, and reducing iron accumulation with iron chelators can improve neuronal survival. Recently, ferroptosis, an iron- dependent form of non-apoptotic cell death, was identified in cancer cells and in organotypic hippocampal slice cultures after glutamate exposure. It is triggered by small molecules or by conditions that inhibit glutathione biosynthesis or glutathione peroxidase 4 (GPX4) activity. This regulated cell death is characterized by extensive iron-dependent lipid peroxidation, which can be suppressed by lipophilic antioxidant ferrostatin-1 or liproxstatin- 1. Ferroptotic cell death also has been shown to occur in brain cells. To date, it has been reported in mouse models of Parkinson disease and ICH. Whether inhibition of ferroptosis by ferrostain-1 or liproxstain-1 reduces ICH injury and improves functional outcomes in aged animals remains unknown. Therefore, this research is intended to characterize ferroptotic cell death in the context of ICH in aged animals. Our long-term goal is to limit ICH injury and improve functional outcomes. The scientific objective of this proposal is to test the hypothesis that inhibition of ferroptosis by ferrostain-1 or liproxstain-1 protects ICH brain and improves functional outcomes. We will further determine whether augmentation of GPX4 activity inhibits ferroptosis and provides cerebroprotection after ICH. In pilot studies, ferroptotoic cell death, characterized by shrunken mitochondria, was detected by transmission electron microscopy in the mouse ICH brain. Additionally, mice treated with ferrostatin-1 after ICH had better neurologic outcomes than mice treated with vehicle. A second, independent, ferroptosis inhibitor, liproxstatin-1, also exhibited marked protection against ICH injury. Together, these novel observations strongly support the premise that inhibition of ferroptosis might reduce ICH injury in aged animals. The first specific aim will determine whether suppression of iron-dependent lipid peroxidation improves histologic and functional outcomes after ICH in aged mice of both sexes. The second specific aim will determine whether overexpression of GPX4 is cerebroprotective after ICH. This study will provide novel evidence that ferroptotic cell death, in addition to other regulated cell death pathways, is prominent in the brains of aged animals with ICH. It will also provide insight into the molecular mechanism by which increased GPX4 activity prevents post-ICH ferroptosis. Work on the proposed project could render new drugs/treatments for patients with ICH. Successful validation of lipid peroxidation inhibitors in the ICH models of aged animals will provide the rationale and proof-of-concept for future preclinical and clinical trials.

脑出血后抑制铁凋亡自发性脑内出血（ICH）是中风亚型，死亡率和发病率最高。因为在ICH期间，大量血液被释放到细胞外空间中，所以血红蛋白/游离血红素对于大脑恢复非常重要。血红素被血红素加氧酶降解为铁， biliverdin和一氧化碳。重要的是，大脑内的铁积聚有助于次要大脑 ICH后受伤。实际上，铁毒性有助于胶原酶诱导的小鼠出血性脑损伤，并且用铁螯合剂减少铁的积累可以改善神经元存活。最近，铁，铁 - 在癌细胞和器官海马切片中鉴定出非凋亡细胞死亡的依赖形式谷氨酸暴露后的培养物。它是由小分子或抑制谷胱甘肽的条件触发的生物合成或谷胱甘肽过氧化物酶4（GPX4）活性。这种调节的细胞死亡的特征是广泛铁依赖性脂质过氧化，可以通过亲脂性抗氧化剂的亚毒素1或脂肪毒素抑制 1。脑细胞中还显示了铁凋亡细胞死亡。迄今为止，它已经在鼠标中报道了帕金森病和ICH的模型。 Ferrostain-1或Liproxstain-1对抑制铁毒性是否降低 ICH损伤并改善了老年动物的功能结果，尚不清楚。因此，这项研究是旨在表征衰老动物ICH的背景下的铁毒细胞死亡。我们的长期目标是限制 ICH伤害并改善功能结果。该提议的科学目的是检验以下假设。 Ferrostain-1或liproxstain-1抑制铁蛋白毒性可保护ICH大脑并改善功能结果。我们将进一步确定GPX4活性的增强是否抑制了铁铁作用并提供脑保护在ICH之后。在试点研究中，通过线粒体缩小的特征的螺纹细胞死亡被检测到小鼠ICH脑中的透射电子显微镜。另外，在ICH后用Ferrostatin-1处理的小鼠与用车辆治疗的小鼠相比，神经系统结局更好。第二个独立的铁铁抑制剂， Liproxstatin-1也表现出明显的防止ICH损伤的保护。这些新颖的观察在一起很强烈支持以下前提：抑制螺栓吞噬可能会减少老年动物的ICH损伤。第一个特定目标将确定抑制铁依赖性脂质过氧化是否可以改善组织学和功能两性老年小鼠的ICH之后的结果。第二个特定目标将确定是否过表达 ICH之后，GPX4的GPX4受到脑外保护。这项研究将提供新的证据，表明铁毒细胞死亡，除其他受调节的细胞死亡途径外，在具有ICH的老年动物的大脑中很突出。它也会提供有关增加GPX4活性可阻止近乎肌凋亡的分子机制的洞察力。在拟议项目上的工作可能会为ICH患者提供新药物/治疗。成功验证老年动物ICH模型中的脂质过氧化抑制剂将为概念和概念验证提供证明未来的临床前和临床试验。