Quantitation of Simultaneous Hydrogen Peroxide and Dopamine Dynamics In Vivo

体内过氧化氢和多巴胺动力学的同时定量

• 批准号: 8489368
• 负责人: LESLIE A SOMBERS
• 金额: $ 27.61万
• 依托单位: NORTH CAROLINA STATE UNIVERSITY RALEIGH
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-09-30 至 2016-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8489368
• 关键词: Address; Agonist; American; Animals; Antiparkinson Agents; Autopsy; Autoreceptors; Behavior; Biological; Biological Process; Biology; Brain; Brain region; Cell Nucleus; Chemicals; Cognitive; Complex; Consensus; Corpus striatum structure; Data; Development; Diffusion; Disease; Dopamine; Dorsal; Dose; Equilibrium; Exhibits; Experimental Models; Extracellular Space; Functional disorder; Generations; Goals; Gold; Health; Hydrogen Peroxide; Investigation; Kinetics; Knowledge; Lesion; Life; Light; Location; Measurement; Measures; Metabolic; Metabolism; Methods; Microelectrodes; Mission; Mitochondria; Molecular; Motor; Neurodegenerative Disorders; Neurotoxins; Normal Range; Organism; Oxidation-Reduction; Oxidative Stress; Oxidopamine; Parkinson Disease; Pathogenesis; Pathway interactions; Pharmaceutical Preparations; Phenylalanine; Physiological; Play; Process; Production; Public Health; Rattus; Reactive Oxygen Species; Research; Research Proposals; Resolution; Role; Scanning; Secondary Parkinson Disease; Signal Transduction; Signaling Molecule; Source; Specificity; Substantia nigra structure; Symptoms; System; Techniques; Therapeutic Intervention; Time; Toxin; Ventral Tegmental Area; area striata; base; brain tissue; burden of illness; carbon fiber; clinically relevant; dopaminergic neuron; falls; improved; in vivo; innovation; mathematical model; molecular dynamics; motor control; motor impairment; neurochemistry; neurotransmission; new technology; oxidative damage; prevent; research study; response; small molecule; uptake

DESCRIPTION (provided by applicant): There is a fundamental gap in understanding how oxidative damage contributes to pathogenesis. Thus, the long-term goal is to elucidate how the release/clearance dynamics of several reactive oxygen species and small molecules in the brain underlie neurodegenerative disease states involving oxidative stress. Hydrogen peroxide (H2O2) is a reactive oxygen species that also serves as an important signaling molecule in normal brain function. Because H2O2 serves these distinct biological roles, H2O2 concentrations likely rise and fall in the extracellular space with precise spatial and temporal resolution, such that functional levels can be achieved for signaling while the pathological consequences resulting from unregulated generation are prevented. However, studies aimed at elucidating these dynamics have been hindered by the lack of a method for probing dynamic H2O2 fluctuations in living systems with molecular specificity. The goals of this research proposal are to enable the quantitative analysis of endogenous H2O2 fluctuations in real-time, and to elucidate how these molecular dynamics modulate those of dopamine (DA) in intact, functional brain tissue. H2O2 is implicated in the pathogenesis of Parkinson's disease. Simultaneous H2O2 and DA measurements will enable regulatory kinetics and mechanisms to be unraveled, investigation of the alteration of these mechanisms by disease or pharmacological agents, and clarification of the neurochemical processes that underlie motor dysfunction. Carbon-fiber microelectrodes will be employed with fast-scan cyclic voltammetry, as this approach provides a quantitative view of neurotransmission in discrete brain locations in real-time. The specific aims combine the development of new technology with innovative applications. They are: 1. To enable the precise characterization of H2O2 fluctuations in the extracellular space of specific brain nuclei, shedding light on its modulatory signaling role, extrasynaptic lifetime, sphere of influence, and diffusion profile under both normal and pathological conditions. These experiments will also demonstrate the extent to which various sources of H2O2 contribute to signaling within select brain nuclei. 2. To elucidate the precise physiological interaction between H2O2 and DA, and the role that these molecular dynamics play in the onset of motor complications associated with Parkinson's disease. In order to achieve these aims, powerful mathematical models will be developed and validated that can be used to interpret the effects of pharmacological agents on the balance between H2O2 generation and clearance. Existing analytical techniques will be modified to enable improved quantitative assessment in the face of chemical variability. The proposed research is significant because the results are expected to vertically advance and expand our understanding of the physiological roles played by H2O2 in the brain, and to shed light on whether oxidative stress is an initiator of dopaminergic dysfunction, or a consequence of that process. Ultimately, such knowledge will inform the development of improved therapeutic interventions, neuroprotective strategies, and promising antiparkinsonian drugs based on redox biology.

描述（由申请人提供）：了解氧化损伤如何有助于发病机理存在基本差距。 因此，长期目标是阐明如何涉及氧化应激的神经退行性疾病状态下的几种活性氧和小分子的释放/清除动力学。 过氧化氢（H2O2）是一种活性氧，在正常脑功能中也是重要的信号分子。 由于H2O2发挥了这些独特的生物学作用，因此H2O2浓度可能会以精确的空间和时间分辨率在细胞外空间中升高，因此可以在信号传导中达到功能水平，而预防了由不受监管的产生产生的病理后果。 然而，由于缺乏探测具有分子特异性的生活系统中动态H2O2波动的方法，旨在阐明这些动力学的研究受到了阻碍。 该研究建议的目标是实时对内源性H2O2波动进行定量分析，并阐明这些分子动力学如何在完整的功能性脑组织中调节多巴胺（DA）的动力学。 H2O2与帕金森氏病的发病机理有关。 同时进行H2O2和DA测量将使调节动力学和机制得以解散，调查通过疾病或药理剂对这些机制的改变，并阐明基于运动功能障碍的神经化学过程。 碳纤维微电极将采用快速扫描的循环伏安法进行，因为这种方法可实时地在离散的大脑位置中定量视图。 具体目的将新技术的开发与创新应用结合在一起。 它们是：1。为了使特定脑核的细胞外空间中H2O2波动的精确表征，在正常和病理条件下散发出其调节信号传导作用，影响范围的调节信号传导作用，影响范围以及扩散谱。 这些实验还将证明各种H2O2来源在选择脑核内信号传导的程度。 2。阐明H2O2和DA之间的精确生理相互作用，以及这些分子动力学在与帕金森氏病有关的运动并发症发作中所起的作用。 为了实现这些目标，将开发和验证强大的数学模型，以解释药理剂对H2O2生成和清除之间平衡的影响。 面对化学变异性，将修改现有的分析技术，以实现改进的定量评估。 拟议的研究很重要，因为预计结果将垂直提高和扩展我们对H2O2在大脑中扮演的生理作用的理解，并阐明氧化应激是多巴胺能功能障碍的发起者还是该过程的结果。 最终，这种知识将为改进的治疗干预措施，神经保护策略以及基于氧化还原生物学的反帕金森药物的发展提供依据。