Mechanisms of Neuronal Apoptosis in Vivo

体内神经元凋亡机制

基本信息

批准号：
7369690
负责人：
LEE J MARTIN
金额：
$ 31.24万
依托单位：
JOHNS HOPKINS UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2000
资助国家：
美国
起止时间：
2000-03-01 至 2010-02-28
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7369690
关键词：
Ablation Acute Animal Model Apoptosis Apoptotic Area Autophagocytosis Award Axon Axotomy Bad protein Biological Models Brain Calcineurin Cell Death Cessation of life DNA DNA Damage Data Dendrites Development Distal Distant Dorsal Dynein ATPase Elevation Event Family Figs - dietary Foundations Genes Genomics Goals Grant Human In Situ Injury Interneurons Lateral Geniculate Body Link Location Mediating Mediation Mediator of activation protein Membrane Mitochondria Modeling Molecular Morphology Motor Movement Mus N-Methyl-D-Aspartate Receptors Nerve Degeneration Nervous system structure Neurodegenerative Disorders Neurologic Neurons Nitric Oxide Nitric Oxide Synthase Type I Noxae Occipital lobe Oxidative Stress Peroxonitrite Presynaptic Terminals Principal Investigator Process Production Protein Dephosphorylation Protein Overexpression Proteins Puma Reactive Nitrogen Species Reactive Oxygen Species Retrograde Degeneration Role Role playing therapy Signal Transduction Site Source Structure Subcellular Fractions System TP53 gene Testing Thalamic structure Up-Regulation Work anterograde transport caspase-3 cellular imaging day deprivation improved in vivo in vivo Model mitochondrial dysfunction neuron apoptosis neuronal cell body neuroprotection research study response superoxide dismutase 1 trafficking transcription factor uptake

项目摘要

DESCRIPTION (provided by applicant): Neurons in the nervous system undergo retrograde degeneration in neurodegenerative diseases and after acute neurological insults. This grant was awarded previously to characterize an animal model of retrograde degeneration of neurons in the dorsal lateral geniculate nucleus (dLGN) induced by target ablation, and to identify molecular mediators of this cell death. We found that this retrograde neurodegeneration is apoptosis, unequivocally defined by its structure, mediation by Bax (a multidomain Bcl-2 family death effector) and p53, and caspase-3 signaling. This cell death emerges with accumulation of perikaryal mitochondria, oxidative damage to DNA, and subcellular translocations of death effectors, and is modulated by neuronal nitric oxide synthase (nNOS). Previous and new experiments, using in situ cell imaging, show that preapoptotic, target-deprived dLGN neurons accumulate mitochondria prior to cell body shrinkage. We hypothesize that these mitochondria are derived from the axon/synaptic terminals. In this grant renewal we will use our model of apoptosis in mouse brain, in which dLGN neurons undergo apoptosis over 7 days after occipital cortex ablation, to study mitochondrial mechanisms of apoptosis in neurons in vivo. In Aim 1 we will identify sources of the accumulating mitochondria and will test the hypothesis that mitochondria return via dynein motors to the dLGN neuron cell body from the remote site of injury in an altered state defined by their capacity for generating reactive oxygen species (ROS) and content of BH3-only death proteins (Bad, Puma, and Noxa). New experiments also suggest that preapoptotic dLGN neurons accumulate intracellular Ca2+. In Aim 2 we will identify possible mechanisms of intracellular Ca2+ accumulation and the preapoptotic roles of mitochondrial Ca uptake and calcineurin-mediated Bad dephosphorylation and mitochondrial translocation. In Aim 3 we will examine the hypothesis that nNOS activation in target-deprived dLGN neurons leads to peroxynitrite production, intracellular Zn2+ accumulation, and mitochondrial dysfunction. This work can define a new mitochondrial mechanism for target deprivation-induced neurodegeneration and can improve the understanding of the cellular and molecular mechanisms of neuronal apoptosis in vivo

描述（由申请人提供）：神经系统中的神经元在神经退行性疾病和急性神经系统损伤后经历逆行变性。该赠款先前是为了表征靶消融诱导的背侧副核（DLGN）中神经元逆行变性的动物模型，并确定了该细胞死亡的分子介质。我们发现，这种逆行神经变性是凋亡，明确定义了其结构，Bax（多域Bcl-2家族死亡效应子）和p53的介导，以及caspase-3信号传导。该细胞死亡是随着线粒体周围的线粒体的积累，对DNA的氧化损伤以及死亡效应子的亚细胞易位的，并由神经元一氧化氮合酶（NNOS）调节。使用原位细胞成像的上一项和新实验表明，原凋亡，靶向的DLGN神经元在细胞体收缩之前会积累线粒体。我们假设这些线粒体源自轴突/突触末端。在此赠款更新中，我们将使用小鼠脑中凋亡模型，其中DLGN神经元在枕皮层消融后的7天内经历凋亡，研究体内神经元细胞凋亡的线粒体机制。在AIM 1中，我们将确定线粒体积累的来源，并将检验以下假设：线粒体通过Dynein Motors从偏远的受伤部位返回DLGN神经元细胞体，其因其产生活性氧（ROS）的能力而定义的变化状态，而BH3型死亡蛋白（ROS）和NON NON，PUMA和NONESXA和NONXA）。新的实验还表明，原胞菌DLGN神经元积累了细胞内Ca2+。在AIM 2中，我们将确定细胞内Ca2+积累的可能机制以及线粒体Ca摄取和钙调蛋白介导的不良去磷酸化和线粒体易位的原始作用。在AIM 3中，我们将研究以下假设：靶局部剥夺DLGN神经元中的NNO激活会导致过氧亚硝酸盐产生，细胞内Zn2+积累和线粒体功能障碍。这项工作可以定义一种新的线粒体机制，用于靶剥夺引起的神经变性，并可以提高对体内神经元凋亡的细胞和分子机制的理解