Effects of opiates on neurons and their impact on HIV neuropathology

阿片类药物对神经元的影响及其对 HIV 神经病理学的影响

• 批准号: 10058827
• 负责人: Olimpia Meucci
• 金额: $ 44.38万
• 依托单位: DREXEL UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-07-01 至 2023-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10058827
• 关键词: Abeta synthesis; Affect; Aging; Amyloid; Amyloid beta-Protein; Amyloid beta-Protein Precursor; Animal Model; Animals; Anti-Retroviral Agents; Area; Brain; Brain region; CXCL12 gene; CXCR4 gene; Cells; Chronic; Cognitive deficits; Critical Pathways; Dendritic Spines; Development; Disease; Disease model; Drug user; Endosomes; Engineering; Ethics; Evaluation; Experimental Models; Exposure to; Ferritin; Funding; Goals; HIV; HIV Envelope Protein gp120; HIV-associated neurocognitive disorder; Hippocampus (Brain); Homeostasis; Human; Impaired cognition; In Vitro; Inflammation; Inhibitory Synapse; Iron; Iron Chelating Agents; Iron-Binding Proteins; Learning; Life Style; Light; Macaca; Maintenance; Measurement; Measures; Mediating; Mediator of activation protein; Membrane Microdomains; Memory; Modeling; Molecular; Monitor; Morphine; Morphology; Neurons; Neurotoxins; Opioid; Pathway interactions; Patients; Performance; Prefrontal Cortex; Property; Protein Family; Proteins; Proteolysis; Rattus; Recording of previous events; Recovery; Regulation; Research; Rodent; Rodent Model; Role; SIV; Signal Transduction; Simplexvirus; Structure; Substance abuse problem; Synapses; Testing; Therapeutic; Tissues; Up-Regulation; Vertebral column; Viral; Viral Proteins; abeta oligomer; amyloid precursor protein processing; amyloidogenesis; base; beta secretase; brain tissue; chemokine; cognitive performance; cognitive task; comorbidity; density; excitotoxicity; in vivo; inhibitor/antagonist; iron metabolism; memory process; neuronal transport; neuropathology; neurotoxic; neurotransmission; novel; opioid abuse; opioid use; preservation; prevent; protein degradation; protein expression; secretase; tool

Project Summary/Abstract HIV-associated neurocognitive disorders (HAND) persist in virally suppressed patients. HAND is a heterogeneous disease that is characterized by chronic low-level inflammation, excitotoxicity, presence of neurotoxic HIV proteins, altered APP processing, and other factors that aggravate neuronal structure and function. Opioid use is common among HIV+ patients and thought to contribute to HAND, although this remains controversial. Studies from the previous funding period suggest that morphine can augment HAND by altering APP processing through a novel, iron-dependent pathway. Toxic APP cleavage products are known to reduce dendritic spines in several brain areas, which are critical mediators of learning and memory. Surprisingly, the effects of APP cleavage products on dendritic spines of the prefrontal cortex (PFC), which is an area of critical importance to HAND, have not been studied in depth. This project will elucidate the role of altered APP processing in morphine and HIV-induced neuronal deficits in the PCF. Studies will unravel the interaction between HIV and Aβ proteins and determine whether morphine can contribute to alteration of APP processing and spines in HAND. Research in aim 1 will concentrate on the effect of Aβ oligomers on dendritic spine structure and function in PFC neurons, in the presence and absence of HIV neurotoxins or morphine. These in vitro and in vivo studies will define meaningful changes in dendritic spine density/morphology/turnover in PFC neurons, and provide a full assessment of exogenously added Aβ actions in this critical brain area (the role of endogenous Aβ will be further tested in aim 3). The main goal of aim 2 is to establish the extent to which µ-opioids can affect amyloidogenesis through modulation of neuronal iron. These mechanistic studies are based on our recent discoveries suggesting a role for iron in morphine-mediated dendritic spine reduction in cortical neurons. They are also supported by the finding that endosome deacidification leads to increase of cytosolic Fe2+ and Aβ. Importantly, cytosolic Fe2+ regulates APP expression whilst endolysosomal pH modulates protein degradation. In aim 3, we will employ newly generated molecular tools able to shift APP processing to the α-cleavage pathway or prevent APP cleavage by β-secretases. After functional testing in primary cultures, the most promising constructs will be expressed in PFC neurons of HAND animal models to determine how effectively they reduce Aβ levels in the presence of HIV proteins/morphine and if Aβ reduction contributes to recovery of PFC cognitive tasks. This proposal will shed light on iron-dependent mechanisms of accelerated cognitive decline in HIV+/opiate abusing subjects, which is becoming increasingly relevant as ART- treated patients live longer.

项目概要/摘要 HIV 相关神经认知障碍（HAND）在病毒抑制的患者中持续存在。 异质性疾病，其特征为慢性低水平炎症、兴奋性毒性、存在 神经毒性 HIV 蛋白、改变的 APP 处理以及其他加剧神经结构和 阿片类药物的使用在 HIV+ 患者中很常见，并且被认为会导致 HAND，尽管这也是如此。 上一个资助期的研究表明吗啡可以通过以下方式增强 HAND： 众所周知，有毒 APP 裂解产物通过一种新颖的铁依赖性途径改变 APP 加工。 减少几个大脑区域的树突棘，这些区域是学习和记忆的关键介质。 令人惊讶的是，APP 裂解产物对前额皮质 (PFC) 树突棘的影响， 对于 HAND 来说至关重要的一个领域尚未得到深入研究，该项目将阐明其作用。 PCF 中吗啡和 HIV 诱导的神经元缺陷中 APP 处理的改变将揭开谜底。 HIV 和 Aβ 蛋白之间的相互作用，并确定吗啡是否有助于 APP 的改变 目标 1 的研究将集中于 Aβ 寡聚物对树突的影响。 在存在或不存在 HIV 神经毒素或吗啡的情况下，PFC 神经元的脊柱结构和功能。 这些体外和体内研究将定义树突棘密度/形态/周转率的有意义的变化 PFC 神经元，并提供对这一关键大脑区域（即外源添加的 Aβ 作用）的全面评估 内源性 Aβ 的作用将在目标 3) 中进一步测试。目标 2 的主要目标是确定作用的程度。 µ-阿片类药物可以通过调节神经元铁来影响淀粉样蛋白生成。这些机制研究。 基于我们最近的发现，表明铁在吗啡介导的树突棘减少中发挥作用 内体脱酸导致皮层神经元增加的发现也支持了他们。 胞质 Fe2+ 和 Aβ 重要的是，胞质 Fe2+ 调节 APP 表达，同时调节内溶酶体 pH。 在目标 3 中，我们将采用新生成的能够改变 APP 的分子工具。 在功能测试后，处理 α-裂解途径或防止 APP 被 β-分泌酶裂解。 原代培养物中，最有希望的构建体将在 HAND 动物模型的 PFC 神经元中表达 确定在 HIV 蛋白/吗啡存在的情况下它们如何有效地降低 Aβ 水平，以及 Aβ 水平是否降低 该提议将有助于阐明 PFC 认知任务的铁依赖性机制。 HIV+/阿片类药物滥用者的认知能力加速下降，随着 ART- 患者寿命更长。