The ER-mitochondria interface in astrocytes during METH exposure and HIV-1 infection

METH 暴露和 HIV-1 感染期间星形胶质细胞中的 ER-线粒体界面

基本信息

批准号：
10401315
负责人：
Jessica Michelle Proulx
金额：
$ 2.28万
依托单位：
UNIVERSITY OF NORTH TEXAS HLTH SCI CTR
依托单位国家：
美国
项目类别：
财政年份：
2021
资助国家：
美国
起止时间：
2021-05-01 至 2022-12-04
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10401315
关键词：
ATF6 gene Academia Acute Affect Antioxidants Astrocytes Bioenergetics Biological Assay Biology Brain Calcium Cell physiology Cellular Stress Response Chronic Communication Coupling Development Endoplasmic Reticulum Ensure Functional disorder Genus Hippocampus HIV HIV-associated neurocognitive disorder Health Health system Homeostasis Human Impairment Individual Infection Inositol Invaded Investigation Lipids Malondialdehyde Measures Mediating Mediator of activation protein Membrane Metabolic Methamphetamine Mitochondria Modeling Modification Molecular Morphology Nerve Degeneration Neuraxis Neurologic Neurons Organelles Pathogenesis Pathologic Pathology Persons Pharmacology Phenotype Phosphotransferases Protein Kinase Proteins Public Health RNA RNA Interference Regulation Regulatory Pathway Research Research Project Grants Research Training Reticulum Risk Role Scheme Scientist Severities Signal Transduction Site Stimulus Stress Substance Use Disorder Testing Time Training Support Virion Virus Diseases Virus Replication arm base biological adaptation to stress blood-brain barrier permeabilization brain cell career comorbidity defined contribution endoplasmic reticulum stress excitotoxicity extracellular fitness inhibitor insight methamphetamine abuse methamphetamine effect methamphetamine exposure methamphetamine use mitochondrial dysfunction neuroinflammation neuronal survival neuropathology neuroprotection neurotoxic neurotoxicity new therapeutic target novel overexpression prevent response therapeutic target vector

项目摘要

Astrocytes are key regulators of CNS health and neuronal function. Astrocyte mitochondrial dysfunction, such as induced by HIV-1 and METH, threatens the provision of essential metabolic and antioxidant support to neurons. Thus, delineating regulatory pathways that can be targeted to prevent aberrant mitochondria homeostasis in astrocytes will be imperative for ensuring neuronal fitness/survival against CNS pathologies. Direct contact sites between the endoplasmic reticulum (ER) and the mitochondria, termed mitochondrial associated membranes (MAMs), are central hubs for regulating several cellular processes required for homeostasis, including mitochondrial metabolic activity. In fact, the transfer of Ca2+ from the ER to mitochondria is essential for mitochondrial bioenergetics. Recent investigations have also identified unique, yet ill-defined contributions of the three unfolded protein response (UPR) arms in regulating MAM tethering and/or signaling. Briefly, protein kinase RNA-like endoplasmic reticulum kinase (PERK) has been determined as a key regulator for MAM tethering, inositol-requiring kinase 1 (IRE1α) is implicated in regulating MAM-mediated Ca2+ transfer, and activating transcription factor 6 (ATF6) is suspected to participate in MAM formation as it is known to mediate ER elongation and lipid homeostasis. However, these regulatory mechanisms have not yet been fully elucidated. Moreover, while modifications in MAM tethering and signaling have been involved in a number of neurodegenerative pathologies, their presence and participation in astrocyte biology remains to be determined. We hypothesize the ER-mitochondria interface is a key mediator of astrocyte mitochondrial dysfunction via Ca2+ and non-canonical UPR signaling during HIV-1 and METH pathogenesis. The proposed studies will examine changes in astrocyte mitochondrial function, UPR induction, Ca2+ signaling, and MAM formation in response to METH exposure and HIV-1 infection, followed by the delineation of ER-associated mechanisms regulating astrocyte mitochondrial function, and thus metabolic and antioxidant capacity. Aim 1 will evaluate how METH exposure and HIV-1 infection alter astrocyte metabolic and antioxidant capacity. Aim 2 will investigate how the ER-mitochondria interface regulates HIV-1/METH-mediated astrocyte mitochondrial dysfunction. Based on our preliminary findings, we propose to prioritize investigating the roles of PERK and IRE1α in regulating MAM tethering and MAM-mediated Ca2+ transfer, respectively, and how these functions alter astrocyte mitochondrial capacity. These studies will implement pharmacological inhibitors, specific silencing (si)RNAs and overexpression vectors to determine how UPR induction, Ca2+ signaling, and MAM tethering regulate astrocyte mitochondrial health during HIV-1/METH pathogenesis. These findings will help identify underlying mechanisms mediating astrocyte mitochondria dysfunction, which can be therapeutically targeted to optimize the metabolic and antioxidant coupling between astrocytes and neurons to promote neuronal survival during neurodegenerative pathologies.

星形胶质细胞是中枢神经系统健康和神经元功能的关键调节因子。例如由 HIV-1 和冰毒引起的，威胁到提供基本的代谢和抗氧化支持因此，描绘了可以针对防止异常线粒体的调节途径。星形胶质细胞的稳态对于确保神经元针对中枢神经系统病理的适应/生存至关重要。内质网（ER）和线粒体之间的直接接触位点，称为线粒体相关膜（MAM）是调节多种细胞过程的中枢。体内平衡，包括线粒体代谢活动事实上，Ca2+ 从内质网转移到线粒体。对线粒体生物能学至关重要。最近的研究也发现了独特但不明确的特征。三个未折叠蛋白反应 (UPR) 臂在调节 MAM 束缚和/或信号传导中的贡献。简而言之，蛋白激酶 RNA 样内质网激酶 (PERK) 已被确定为关键调节因子对于 MAM 束缚，肌醇需求激酶 1 (IRE1α) 参与调节 MAM 介导的 Ca2+ 转移，激活转录因子 6 (ATF6) 被怀疑参与 MAM 形成，因为已知它可以介导然而，这些调节机制尚未完全阐明。此外，虽然 MAM 系链和信号传导的修改涉及许多神经退行性病理学、它们在星形胶质细胞生物学中的存在和参与仍有待确定。我们一直致力于ER-线粒体界面是星形胶质细胞线粒体功能障碍的关键介质 HIV-1 和 METH 发病过程中通过 Ca2+ 和非经典 UPR 信号传导。拟议的研究将检查星形胶质细胞线粒体功能、UPR 诱导、Ca2+ 的变化信号传导，以及响应 METH 暴露和 HIV-1 感染而形成的 MAM，然后进行描述 ER 相关机制调节星形胶质细胞线粒体功能，从而调节代谢和抗氧化目标 1 将评估冰毒暴露和 HIV-1 感染如何改变星形胶质细胞的代谢和抗氧化能力。目标 2 将研究 ER-线粒体界面如何调节 HIV-1/METH 介导的星形胶质细胞。根据我们的初步发现，我们建议优先研究线粒体功能障碍的作用。 PERK 和 IRE1α 分别调节 MAM 束缚和 MAM 介导的 Ca2+ 转移，以及它们如何发挥作用功能改变星形胶质细胞线粒体能力这些研究将实施药理学抑制剂、特异性抑制剂。沉默 (si)RNA 和过表达载体以确定 UPR 诱导、Ca2+ 信号传导和 MAM 的作用束缚在 HIV-1/METH 发病过程中调节星形胶质细胞线粒体健康这些发现将有所帮助。确定介导星形胶质细胞线粒体功能障碍的潜在机制，这可以用于治疗旨在优化星形胶质细胞和神经元之间的代谢和抗氧化耦合，以促进神经元神经退行性疾病期间的生存。