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：
10259195
负责人：
Jessica Michelle Proulx
金额：
$ 3.5万
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 2023-04-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10259195
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 Exposure to 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 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/antagonist 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

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 Exposure to 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 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/antagonist 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

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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CNS健康和神经元功能的关键调节剂。星形细胞线粒体功能障碍，例如HIV-1和METH诱导的，威胁要提供必需的代谢和抗氧化剂支持神经元。这是划定可以针对的监管途径，以防止异常线粒体星形胶质细胞中的稳态必须确保对CNS病理的神经元健康/生存。内质网（ER）和线粒体之间的直接接触位点称为线粒体相关机制（MAM）是控制几个蜂窝过程所需的中心枢纽稳态，包括线粒体代谢活性。实际上，Ca2+从ER转移到线粒体对于线粒体生物能力是必不可少的。最近的投资还确定了独特但定义不明的在调节MAM绑扎和/或信号传导中，三个展开的蛋白质反应（UPR）臂的贡献。简而言之，蛋白激酶RNA样性内质网激酶（PERK）已确定为关键调节剂对于MAM绑扎，肌醇含量的激酶1（IRE1α）与调节MAM介导的Ca2+转移有关并怀疑激活转录因子6（ATF6）参与MAM形成，因为已知会介导 ER伸长和脂质稳态。但是，这些调节机制尚未完全阐明。此外，尽管MAM绑扎和信号传导的修改涉及许多神经退行性病理，它们的存在和参与星形胶质细胞生物学仍有待确定。我们假设er-ritochontria界面是星形胶质细胞功能障碍的关键介体通过HIV-1和METH发病机理期间的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的变化，UPR诱导，Ca2+ 信号传导和MAM形成，以响应甲基甲基暴露和HIV-1感染，然后进行描述 ER相关的机制，用于标准线粒体功能，因此代谢和抗氧化剂容量。 AIM 1将评估甲基甲基暴露和HIV-1感染如何改变星形胶质细胞代谢和抗氧化剂容量。 AIM 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线粒体功能障碍。根据我们的初步发现，我们建议优先研究 PERK和IRE1α在调节MAM链接和MAM介导的Ca2+转移中，以及如何分别功能会改变星形胶质细胞线粒体能力。这些研究将实施药物抑制剂，特定沉默（SI）RNA和过表达向量，以确定UPR诱导，Ca2+信号传导和MAM 束缚在HIV-1/METH发病机理期间调节星形胶质细胞的线粒体健康。这些发现将有所帮助识别介导星形胶质细胞线粒体功能障碍的潜在机制，可以热旨在优化星形胶质细胞和神经元之间的代谢和抗氧化剂耦合以促进神经元神经退行性病理学期间的生存。