The role of nicotinamide mononucleotide dependent mitochondrial reactive oxygen species generation in acute brain injury

烟酰胺单核苷酸依赖性线粒体活性氧生成在急性脑损伤中的作用

基本信息

批准号：
10618865
负责人：
TIBOR KRISTIAN
金额：
--
依托单位：
BALTIMORE VA MEDICAL CENTER
依托单位国家：
美国
项目类别：
财政年份：
2020
资助国家：
美国
起止时间：
2020-04-01 至 2025-03-31
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10618865
关键词：
Acetylation Acute Acute Brain Injuries Address Affect Age Animal Model Animals Astrocytes Bioenergetics Brain Brain Injuries Brain region Catabolism Cause of Death Cell Death Cell Death Induction Cell Survival Cells Chronic Clinical Clinical Trials Complex Consumption Data Deacetylase Deacetylation Death Rate Disease Dose Drug Metabolic Detoxication Enzymes Failure Female Fluorescence Generations Glucose Glutamate-ammonia-ligase adenylyltransferase Goals Health Heart Arrest High Prevalence Histologic Impairment Injury Ischemia Ischemic Brain Injury Link Long-Term Care Metabolic Metabolism Mitochondria Mitochondrial Proteins Modeling Morphology Myocardial Infarction Nerve Degeneration Neurodegenerative Disorders Neurologic Neurological outcome Neurons Nicotinamide Mononucleotide Nicotinamide adenine dinucleotide Oxygen Pathologic Pathway interactions Pilot Projects Play Poly(ADP-ribose) Polymerases Polymerase Population Process Production Prosencephalon Protein Acetylation Proteins Reactive Oxygen Species Regulation Research Respiration Respiratory physiology Ribose Risk Factors Role SOD2 gene Sirtuins Stroke Superoxides TBI treatment Testing Therapeutic Transgenic Animals Transgenic Mice Traumatic Brain Injury Veterans Work aging population brain cell cell type deprivation disability experimental study improved in vivo insight knockout animal knockout gene male military veteran mitochondrial dysfunction morphometry mouse model neuroprotection novel novel therapeutic intervention nucleotide metabolism overexpression pre-clinical research preservation stroke outcome stroke risk stroke victims therapy development translational approach

Acetylation Acute Acute Brain Injuries Address Affect Age Animal Model Animals Astrocytes Bioenergetics Brain Brain Injuries Brain region Catabolism Cause of Death Cell Death Cell Death Induction Cell Survival Cells Chronic Clinical Clinical Trials Complex Consumption Data Deacetylase Deacetylation Death Rate Disease Dose Drug Metabolic Detoxication Enzymes Failure Female Fluorescence Generations Glucose Glutamate-ammonia-ligase adenylyltransferase Goals Health Heart Arrest High Prevalence Histologic Impairment Injury Ischemia Ischemic Brain Injury Link Long-Term Care Metabolic Metabolism Mitochondria Mitochondrial Proteins Modeling Morphology Myocardial Infarction Nerve Degeneration Neurodegenerative Disorders Neurologic Neurological outcome Neurons Nicotinamide Mononucleotide Nicotinamide adenine dinucleotide Oxygen Pathologic Pathway interactions Pilot Projects Play Poly(ADP-ribose) Polymerases Polymerase Population Process Production Prosencephalon Protein Acetylation Proteins Reactive Oxygen Species Regulation Research Respiration Respiratory physiology Ribose Risk Factors Role SOD2 gene Sirtuins Stroke Superoxides TBI treatment Testing Therapeutic Transgenic Animals Transgenic Mice Traumatic Brain Injury Veterans Work aging population brain cell cell type deprivation disability experimental study improved in vivo insight knockout animal knockout gene male military veteran mitochondrial dysfunction morphometry mouse model neuroprotection novel novel therapeutic intervention nucleotide metabolism overexpression pre-clinical research preservation stroke outcome stroke risk stroke victims therapy development translational approach

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项目摘要

Impairments in mitochondrial functions have been frequently implicated in ischemic brain injury associated with cardiac arrest or stroke. However, the extent to which mitochondrial dysfunction contributes to neurodegeneration is unknown; and the mechanisms leading to mitochondrial failure are not well understood. Recently, it was suggested that an imbalance in mitochondrial fission/fusion dynamics can lead to neurodegeneration and brain damage. Furthermore, overactivation of nicotinamide adenine dinucleotide (NAD)+ degrading poly-ADP-ribose polymerase (PARP1) causes excessive cellular and mitochondrial NAD+ depletion resulting in impaired cell survival. We hypothesize that the nicotinamide mononucleotide (NMN) administration is inhibiting the post-ischemic neurodegeneration by (a) reversing excessive mitochondrial fission via stimulation of mitochondrial NAD+ synthesis that (b) stimulates deacetylation of mitochondrial proteins and leads to (c) reduction of mitochondrial superoxide production. Our preliminary data show that treatment of animals with NAD+ precursor NMN has dramatic neuroprotection effect, reverses the excessive mitochondrial fragmentation and increases the brain mitochondria NAD+ levels. As a downstream result NMN is decreasing mitochondrial proteins acetylation and inhibits mitochondrial reactive oxygen species (ROS) production. The primary goal of this study is to determine the mechanistic link(s) between NMN induced changes in mitochondrial NAD+ metabolism, protein acetylation, ROS generation and inhibition of fission. To address these questions, we propose to: 1. Determine the specific role of sirtuin 3 (SIRT3) in mitochondrial reactive oxygen species (ROS) production, nucleotide metabolism, mitochondrial bioenergetic functions, and dynamics. Cells will be prepared from our three transgenic animal models: (1) animals expressing mitochondria targeted enhanced yellow fluorescence protein (mito-eYFP) alone, (2) animals expressing mito-eYFP and overexpressing SIRT3 (mito-eYFP-SIRT3OE), or (3) mito-eYFP expressing SIRT3 knockout animals (mito-eYFP-SIRT3KO). The role of NMN-induced changes in mitochondrial protein acetylation on mitochondria ROS production, mitochondrial fragmentation and cell death will be determined. Cellular NAD+ metabolism, mitochondrial respiratory function, and mitochondrial fusion and fission will be analyzed and their role in NMN neuroprotection and oxygen glucose deprivation induced cell death will be determined. 2. To study the specific effect of NMN treatment on post-ischemic modulation of mitochondrial dynamics in brain, we will use our transgenic animals that will be subjected to transient forebrain ischemia and the post-ischemic alterations in neuronal mitochondrial morphometry will be examined. In addition, NMN- induced changes in NAD+ metabolism, mitochondrial protein acetylation and mitochondrial ROS generation will be determined. Additionally, NMN-induced changes in NAD+ metabolism, mitochondrial protein acetylation and mitochondrial ROS generation will be determined. Finally, we will assess the effect of NMN treatment on post-ischemic cellular and mitochondrial NAD+ metabolism and mitochondrial respiration. The significance of this work is that it proposes both mechanistic and translational approaches to unravel the mechanisms of NAD+ dependent mitochondrial ROS production, impairment in mitochondrial dynamics and determine its role in acute brain injury. Furthermore, the identification of a novel metabolic link between NAD+ catabolism, acetylation/deacetylation of mitochondrial proteins, mitochondrial ROS generation and inhibition of mitochondrial fission will identify new mechanisms for neuroprotection that could lead to the use of NMN as a therapeutic compound for acute brain injury such as global ischemia, stroke and TBI or chronic neurodegenerative disease, thus potentially have significant impact on the health of Veterans.

线粒体功能的损伤经常与缺血性脑损伤有关与心脏骤停或中风有关。但是，线粒体功能障碍的贡献程度神经退行性是未知的。并且导致线粒体衰竭的机制不好理解。最近，建议线粒体裂变/融合动力学的失衡可以引导神经变性和脑损伤。此外，烟酰胺腺嘌呤二核苷酸的过度活化（NAD）+降解多ADP-核糖聚合酶（PARP1）导致过多的细胞和线粒体NAD+ 耗竭导致细胞存活受损。我们假设烟酰胺单核苷酸（NMN）给药是通过（a）逆转过度的线粒体抑制缺血后神经退行性的通过刺激线粒体NAD+合成的裂变，即（b）刺激线粒体的脱乙酰基化蛋白质并导致（c）线粒体超氧化物的减少。我们的初步数据表明，用NAD+前体NMN治疗动物具有戏剧性神经保护作用，逆转过度的线粒体碎片并增加大脑线粒体NAD+水平。由于下游结果，NMN降低了线粒体蛋白乙酰化和抑制线粒体活性氧（ROS）产生。这项研究的主要目标是确定NMN诱导线粒体NAD+代谢的变化之间的机械链接乙酰化，ROS产生和裂变抑制作用。为了解决这些问题，我们建议： 1。确定Sirtuin 3（SIRT3）在线粒体活性氧（ROS）中的特定作用生产，核苷酸代谢，线粒体生物能功能和动力学。细胞将是从我们的三种转基因动物模型中制备：（1）表达线粒体的动物靶向增强单独使用黄色荧光蛋白（Mito-eyfp），（2）表达Mito-eyfp和过表达SIRT3的动物（mito-eyfp-sirt3oe）或（3）表示SIRT3淘汰动物（mito-eyfp-sirt3ko）的mito-eyfp。这 NMN诱导的线粒体蛋白乙酰化变化在线粒体ROS产生中的作用，将确定线粒体碎片和细胞死亡。细胞NAD+代谢，线粒体将分析呼吸功能，线粒体融合和裂变，它们在NMN中的作用将确定神经保护和氧葡萄糖剥夺引起的细胞死亡。 2。研究NMN处理对线粒体缺血后调节的特定作用大脑中的动力学，我们将使用将受到短暂前脑缺血的转基因动物将检查神经元线粒体形态计量学的缺血后改变。另外，NMN- 诱导NAD+代谢，线粒体蛋白乙酰化和线粒体ROS的变化的变化将确定。此外，NMN诱导的NAD+代谢，线粒体蛋白的变化将确定乙酰化和线粒体ROS的产生。最后，我们将评估NMN的效果在缺血后细胞和线粒体NAD+代谢和线粒体呼吸进行治疗。这项工作的意义在于，它提出了机械和翻译方法揭示NAD+依赖性线粒体ROS的机制，线粒体损伤动力学并确定其在急性脑损伤中的作用。此外，新的代谢环节的识别在NAD+分解代谢之间，线粒体蛋白的乙酰化/脱乙酰化，线粒体ROS的产生线粒体裂变的抑制作用将确定神经保护的新机制，可能导致将NMN用作急性脑损伤的治疗化合物，例如全球缺血，中风和TBI或TBI或因此，慢性神经退行性疾病可能会对退伍军人的健康产生重大影响。