Lipidomic mapping of the cellular anatomy of brain endocannabinoid metabolism

脑内源性大麻素代谢细胞解剖学的脂质组学图谱

• 批准号: 8915234
• 负责人: Andreu Viader
• 金额: $ 3.18万
• 依托单位: SCRIPPS RESEARCH INSTITUTE, THE
• 依托单位国家: 美国
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-09-30 至 2015-10-01
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8915234
• 关键词: 2-arachidonylglycerol; Ablation; Adverse effects; Anti-Inflammatory Agents; Anti-inflammatory; Anxiety; Area; Astrocytes; Brain; Brain region; Clinical; Complex; Degradation Pathway; Development; Eicosanoid Production; Eicosanoids; Endocannabinoids; Enzyme Inhibition; Enzymes; Genetic; Health; Heterogeneity; Hydrolase; Hydrolysis; Image; Inflammatory; Knockout Mice; Laboratories; Lipids; Maps; Mass Spectrum Analysis; Mediator of activation protein; Metabolic; Metabolism; Microglia; Mood Disorders; Mus; Nanostructures; Nerve Degeneration; Nervous system structure; Neurodegenerative Disorders; Neuroglia; Neurons; Organ; Pain; Pathologic Processes; Pathway interactions; Pharmacologic Substance; Physiological; Physiological Processes; Physiology; Production; Role; Safety; Signal Pathway; Signal Transduction; Specimen; Stimulus; Subcellular Anatomy; Substance abuse problem; Technology; Therapeutic; Time; analytical method; base; cannabinoid receptor; cell type; desensitization; endogenous cannabinoid system; frontier; imaging platform; in vivo; intercellular communication; interest; lipoprotein lipase; metabolomics; mouse model; nervous system disorder; neuroinflammation; neuroprotection; novel; research study; tool

DESCRIPTION (provided by applicant): Recent developments in mass spectrometry (MS)-based metabolomic approaches are helping to establish lipid molecules as critical mediators of signal transduction in the nervous system. The endocannabinoid (eCB) 2-arachidonoylglycerol (2-AG), for example, serves as a key metabolic hub connecting the endogenous cannabinoid system (ECS) and pro-inflammatory eicosanoid production in the brain. In this manner, 2-AG signaling pathways modulate pain, anxiety, neuroinflammation, and neurodegeneration and have thus attracted considerable pharmaceutical interest for the treatment of nervous system diseases. Global increases in brain 2-AG, however, can also cause a range of undesirable side-effects. The multiplicity and differential distribution of 2-AG metabolic enzymes may provide a means to target specific brain 2-AG stores to fully capitalize on the development of 2-AG-based therapeutics with acceptable safety profiles. We hypothesize that the inhibition of distinct 2-AG biosynthetic and degradative enzymes will modulate the ECS/eicosanoid signaling network in specific brain cellular compartments to produce anti-inflammatory and neuroprotective effects, while limiting detrimental consequences observed with global ECS agonism or antagonism. This proposal describes experiments that leverage newly generated tools to selectively disrupt 2-AG metabolic enzymes together with the power of MS-based lipidomics to define novel enzymatic targets for the development of eCB-based therapeutics. First, we will map the cellular anatomy of 2-AG degradation pathways in the mouse brain. Specifically, we will use targeted and untargeted lipidomic profiling to examine the compartmentalization of the major brain 2-AG hydrolases (MAGL, ABHD6 and ABHD12) in neurons vs. glia, as well as to characterize cell type-specific metabolic alterations following genetic deletion of these enzymes. Second we will determine whether the inhibition of diacylglycerol lipases (DAGL) a and b, the two main 2-AG biosynthetic enzymes in the brain, can selectively modulate the brain ECS/eicosanoid network. By taking advantage of DAGLa or b knockout mice, we will map the cellular distribution of these two enzymes in the nervous system and assess how their inactivation alters pools of eCBs/eicosanoids basally and in experimental paradigms of neuroinflammation. Finally, we will carry out MS-based metabolic imaging of the anatomical distribution of 2-AG in the brain. We will use a novel Nanostructure-initiator Mass Spectrometry (NIMS) imaging platform to characterize the distribution of 2-AG levels in different brain regions basally and after inhibitio of 2-AG metabolic enzymes. In summary, this project will push the frontiers of applying cutting- edge lipidomic technologies to characterize the cellular and anatomical compartmentalization of the ECS/eicosanoid signaling network and its role in brain intercellular communication, as well as aid the development of novel eCB-based therapeutics for the treatment of nervous system diseases.

描述（由申请人提供）：基于质谱（MS）的代谢组学方法的最新发展正在帮助建立脂质分子作为神经系统信号转导的关键介质。例如，内源性大麻素 (eCB) 2-花生四烯酰甘油 (2-AG) 是连接内源性大麻素系统 (ECS) 和大脑中促炎类二十烷酸产生的关键代谢中心。以这种方式，2-AG信号通路调节疼痛、焦虑、神经炎症和神经变性，因此在治疗神经系统疾病方面引起了相当大的制药兴趣。然而，大脑 2-AG 的整体增加也会导致一系列不良副作用。 2-AG 代谢酶的多样性和差异性分布可能提供一种针对特定大脑 2-AG 储存的方法，以充分利用基于 2-AG 的疗法的开发，并具有可接受的安全性。我们假设，抑制不同的 2-AG 生物合成和降解酶将调节特定脑细胞区室中的 ECS/类二十烷酸信号网络，以产生抗炎和神经保护作用，同时限制通过整体 ECS 激动或拮抗观察到的有害后果。该提案描述了利用新生成的工具选择性破坏 2-AG 代谢酶的实验，以及基于 MS 的脂质组学的能力，以确定用于开发基于 eCB 的疗法的新酶靶标。首先，我们将绘制小鼠大脑中 2-AG 降解途径的细胞解剖图。具体来说，我们将使用靶向和非靶向脂质组学分析来检查主要大脑 2-AG 水解酶（MAGL、ABHD6 和 ABHD12）在神经元与神经胶质细胞中的区室化，以及表征这些酶基因删除后的细胞类型特异性代谢变化。其次，我们将确定抑制二酰基甘油脂肪酶 (DAGL) a 和 b（大脑中两种主要的 2-AG 生物合成酶）是否可以选择性地调节大脑 ECS/类二十烷酸网络。通过利用 DAGLa 或 b 敲除小鼠，我们将绘制这两种酶在神经系统中的细胞分布图，并评估它们的失活如何在基础上和神经炎症的实验范例中改变 eCB/类二十烷酸库。最后，我们将对 2-AG 在大脑中的解剖分布进行基于 MS 的代谢成像。我们将使用新型纳米结构引发剂质谱 (NIMS) 成像平台来表征 2-AG 水平在不同大脑区域的基底和 2-AG 代谢酶抑制后的分布。总之，该项目将推动应用尖端脂质组学技术的前沿，以表征 ECS/类二十烷酸信号网络的细胞和解剖区划及其在大脑细胞间通讯中的作用，并帮助开发基于 eCB 的新型神经系统疾病疗法。