CHOROID PLEXUS AS A TARGET IN METAL-INDUCED NEUROTOXICITY

脉络丛作为金属引起的神经毒性的靶点

• 批准号: 8435445
• 负责人: WEI ZHENG
• 金额: $ 32.9万
• 依托单位: PURDUE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-03-01 至 2015-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8435445
• 关键词: Affect; Alzheimer' s Disease; Amyloid; Amyotrophic Lateral Sclerosis; Animals; Blood; Blood - brain barrier anatomy; Blood capillaries; Brain; Brain region; Carrier Proteins; Cell Line; Cells; Cerebrospinal Fluid; Collaborations; Copper; Data; Epithelial; Epithelium; Equilibrium; Exposure to; Fluorescence; Foundations; Funding; Goals; Grant; Homeostasis; Human; In Vitro; Lead; Location; Manganese; Metals; Modeling; Molecular; Neuraxis; Neurodegenerative Disorders; Oxidative Stress; Parkinson Disease; Parkinsonian Disorders; Perfusion; Physics; Prion Diseases; Process; Production; Rattus; Regulation; Relative (related person); Research; Research Project Grants; Roentgen Rays; Role; SLC11A2 gene; Saliva; Scanning; Small Interfering RNA; Structure of choroid plexus; Surface; Synchrotrons; System; Techniques; Testing; Time; Tissues; Toxic Environmental Substances; Western Blotting; Work; base; blood cerebrospinal fluid barrier; brain tissue; capillary; cohort; design; in vivo; inhibitor/antagonist; insight; lead exposure; neurotoxicity; novel; professor; public health relevance; stable cell line; three-dimensional modeling; toxic metal; trafficking; uptake

DESCRIPTION (provided by applicant): Altered brain copper (Cu) homeostasis has been associated with idiopathic Parkinson's disease (IPD), Alzheimer's disease (AD), amyotrophic lateral sclerosis (ALS), and Prion disease. We have recently discovered that Cu levels in blood and saliva of Mn-exposed workers from human cohorts are significantly increased, and so are the Cu levels in the CSF and brain tissues of Mn- exposed animals. While the presence of transporters possibly responsible for Cu transport in brain barriers such as Cu transport protein-1 (Ctr1), divalent metal transporter-1 (DMT1) and ATP7A has been demonstrated, how Cu is transported by these transporters in brain barriers and by what mechanism exposure to manganese (Mn) alters the expression and function of these transporters are unknown. This research project is designed to test the hypothesis that the choroid plexus, a brain tissue forming a barrier between the blood and cerebrospinal fluid (CSF), regulates Cu transport between the blood and CSF through the critical transporters; exposure to Mn alters the functions of these transporters, leading to a distorted Cu homeostasis in the CSF. To test this hypothesis, we have designed 4 specific aims. In Aim 1, we will determine if subchronic exposure to Mn in a rat model alters the expression of Ctr1, DMT1 and ATP7A in blood-brain barrier (BBB) and blood-CSF barrier (BCB), leading to an increased influx of Cu from the blood to brain parenchyma and a decreased Cu efflux from the CSF to blood. In Aim 2, we will reveal if Ctr1 and DMT1 coordinate the Cu uptake on the surface of the BBB and BCB and if Mn exposure disrupts these processes, leading to cellular overload of Cu by the brain barrier cells. Aim 3 is designed to investigate if the intracellular trafficking of ATP7A determines the direction of Cu transport by the BCB and if Mn exposure, by acting on ATP7A, may alter the direction of Cu transport between the blood and the CSF. Finally, in Aim 4, we will use the synchrotron rapid scanning X-ray fluorescence (RS-XRF) technique, by collaboration with the professor in Purdue's Physics department, to establish 3D model to simultaneously localize and quantify Cu, Fe, Mn and Zn in brains of Mn-exposed rats. The studies proposed in this application will define the inter-relationship between Ctr1, DMT1 and ATP7A in brain barriers with regard to their subcellular locations, roles in transport of Cu, and their regulation as affected by Mn exposure; will provide the insight into the molecular mechanism by which Mn affects Cu transport by brain barriers; and will ultimately provide a better understanding of Cu dysregulation-related neurodegenerative diseases.

描述（由申请人提供）：改变的脑铜（Cu）稳态与特发性帕金森病（IPD）、阿尔茨海默病（AD）、肌萎缩侧索硬化症（ALS）和朊病毒病相关。我们最近发现，来自人类队列的锰接触工人的血液和唾液中的Cu水平显著升高，并且锰接触动物的CSF和脑组织中的Cu水平也显著升高。虽然已经证明了可能负责脑屏障中Cu转运的转运蛋白如Cu转运蛋白-1（Ctr 1）、二价金属转运蛋白-1（DMT 1）和ATP 7A的存在，但这些转运蛋白在脑屏障中如何转运Cu以及暴露于锰（Mn）通过何种机制改变这些转运蛋白的表达和功能尚不清楚。本研究项目旨在验证以下假设：脉络丛（一种在血液和脑脊液（CSF）之间形成屏障的脑组织）通过关键转运蛋白调节血液和CSF之间的Cu转运;暴露于Mn会改变这些转运蛋白的功能，导致CSF中Cu稳态的扭曲。为了验证这一假设，我们设计了四个具体目标。在目标1中，我们将确定大鼠模型中亚慢性暴露于锰是否会改变血脑屏障（BBB）和血CSF屏障（BCB）中Ctr 1、DMT 1和ATP 7A的表达，导致血液中铜流入量增加到脑实质，并减少从CSF到血液的铜流出量。在目标2中，我们将揭示Ctr 1和DMT 1是否协调BBB和BCB表面上的Cu摄取，以及Mn暴露是否破坏这些过程，导致脑屏障细胞对Cu的细胞过载。目的3旨在研究ATP 7A的细胞内运输是否决定BCB的Cu转运方向，以及Mn暴露是否通过作用于ATP 7A而改变血液和CSF之间的Cu转运方向。最后，在目标4中，我们将使用同步加速器快速扫描X射线荧光（RS-XRF）技术，通过与普渡大学物理系的教授合作，建立三维模型，同时定位和定量的Cu，Fe，Mn和Zn在锰暴露大鼠的大脑。本申请中提出的研究将确定Ctr 1、DMT 1和ATP 7A在脑屏障中的相互关系，包括它们的亚细胞位置、在Cu转运中的作用以及它们受Mn暴露影响的调节;将提供对Mn影响脑屏障Cu转运的分子机制的深入了解;并将最终提供一个更好的理解铜失调相关的神经退行性疾病。