5/11 Microglial MyD88 in Mouse Models of Excessive Alcohol Intake

5/11 过量饮酒小鼠模型中的小胶质细胞 MyD88

• 批准号: 10411121
• 负责人: Staci D Bilbo
• 金额: $ 39.5万
• 依托单位: DUKE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-02-10 至 2027-01-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10411121
• 关键词: Ablation; Acute; Alcohol consumption; Alcohols; Astrocytes; Behavior; Brain; Brain Diseases; Buffers; Chronic; Complement; Data; Dependence; Development; Disease; Electrophysiology (science); Exhibits; Extracellular Matrix; Gene Expression Profile; Goals; Heavy Drinking; Immune; Impairment; Inflammation; Inflammation Mediators; Inflammatory; Inhibitory Synapse; Injections; Insula of Reil; Interleukin-1; Interneuron function; Interneurons; Knockout Mice; Lead; Link; Lipopolysaccharides; Measures; Mediating; Microglia; Morphology; Mus; Myelogenous; Neuraxis; Neuroimmune; Neuronal Plasticity; Neurons; Oxidative Stress; Parvalbumins; Pathology; Phagocytosis; Pharmaceutical Preparations; Production; Proteins; Protocols documentation; Receptor Activation; Regulation; Research Personnel; Resistance; Role; Signal Transduction; Stimulus; Structure; Synapses; TNF gene; Testing; Toll-like receptors; Transgenic Organisms; Viral Vector; Western Blotting; addiction; adverse outcome; alcohol exposure; alcohol response; alcohol use disorder; base; cell type; chemokine; chronic alcohol ingestion; critical period; cytokine; design; designer receptors exclusively activated by designer drugs; drinking; drinking behavior; frontal lobe; innovation; male; mouse model; neuroinflammation; neuropsychiatric disorder; novel; pathogen; prevent; response; single-cell RNA sequencing; synaptic function

Abstract Repeated alcohol exposure can be a potent neuroinflammatory stimulus. Alcohol activates microglia within the brain via toll-like-receptors (TLRs); this activation leads to production of inflammatory mediators which contribute to dependence and abuse 4,5. Fast spiking parvalbumin positive (PV+) GABAergic interneurons (PVIs) are critical for normal brain function. PVIs are often surrounded by specialized extracellular matrix molecules called perineuronal nets (PNNs) which protect and buffer them from inflammation and oxidative stress. Notably, increased PNNs are implicated in alcohol use disorder (AUD), which may be due to a "locking in" of critical neuroplasticity mechanisms that underlie habitual behavior such as drug seeking in the face of adverse consequences 2. Our preliminary data show that mice with microglial-specific ablation of the critical TLR adaptor molecule myeloid differentiation primary response 88 [MyD88] (Cx3cr1-CreBT-MyD88f/f [hereafter called "Cre+ mice"]) exhibit decreased proinflammatory responses (e.g. IL-1, TNF) to a lipopolysaccharide (LPS) injection compared to Cre- controls, as expected. Surprisingly, however, in response to LPS, male (but not female) Cre+ mice exhibit increased numbers of PVIs and PV/PNN interactions within the frontal cortex. Cre+ male mice further exhibit markedly increased alcohol intake in an acute drinking-in-the dark (DID) protocol compared to controls, consistent with findings from previous INIA-Neuroimmune projects using MyD88-/- (knockout) mice and chronic alcohol paradigms 6. Taken together, these data suggest microglia critically regulate PVI number and/or PNN envelopment in response to inflammatory signals via MyD88 signaling, and that increased PVI/PNN interactions in the absence of MyD88 may underlie increased drinking in Cre+ mice. The overall goal of this proposal is to test this hypothesis. Aim 1 will determine if microglial-MyD88 regulates the number of PVIs and/or PNN interactions directly in response to chronic alcohol by assessing the phagocytosis of PVI-specific inhibitory synapses and PNNs by microglia. Aim 2 will determine if microglial-MyD88 regulates the number of PVIs and/or PNN interactions indirectly in response to chronic alcohol by assessing the "secretome" of microglia and the production of PNN components by astrocytes and PVIs. Aim 3 will determine the role of PVIs and/or PNN interactions in excessive drinking behavior in mice with and without microglial MyD88 by assessing the impact of (1) degrading PNNs and (2) chemogenetic inhibition vs. activation of microglia on excessive drinking. This is an innovative new project designed to complement existing strengths of several other INIA-Neuroimmune investigators. If completed, these data would be the first to show a direct role for microglia in PVI/PNN development and their role in excessive drinking, which could lead to novel treatment options.

抽象的 反复接触酒精可能会刺激神经炎症。 通过 Toll 样受体 (TLR) 进入大脑；这种激活导致炎症介质的产生，从而有助于 快速尖峰小白蛋白阳性 (PV+) GABA 能中间神经元 (PVI) 至关重要。 为了保证正常的大脑功能，PVI 通常被称为特殊细胞外基质的分子包围。 神经周围网（PNN）可以保护和缓冲它们免受炎症和氧化应激的影响。 PNN 增加与酒精使用障碍 (AUD) 有关，这可能是由于“锁定”关键酒精所致 神经可塑性机制是习惯行为的基础，例如面对不利时寻求药物 后果 2. 我们的初步数据表明，关键 TLR 接头的小胶质细胞特异性消融的小鼠 分子骨髓分化初级反应 88 [MyD88] (Cx3cr1-CreBT-MyD88f/f [以下称为“Cre+ 小鼠”]）对脂多糖（LPS）注射表现出促炎反应（例如 IL-1、TNF）降低 然而，令人惊讶的是，与 Cre- 对照相比，雄性（但不是雌性）Cre+ 对 LPS 做出了反应。 Cre+ 雄性小鼠的额叶皮质内 PVI 和 PV/PNN 相互作用的数量进一步增加。 与对照组相比，急性黑暗饮酒（DID）方案中的酒精摄入量显着增加， 与之前使用 MyD88-/-（敲除）小鼠和慢性病的 INIA-神经免疫项目的结果一致 酒精范式 6. 总而言之，这些数据表明小胶质细胞严格调节 PVI 数量和/或 PNN 包络通过 MyD88 信号传导响应炎症信号，从而增加 PVI/PNN 缺乏 MyD88 时的相互作用可能是 Cre+ 小鼠饮酒增加的基础。 该提案是为了测试这一假设，目的 1 将确定小胶质细胞-MyD88 是否调节 PVI 的数量。 和/或通过评估 PVI 特异性的吞噬作用直接响应慢性酒精的 PNN 相互作用 目标 2 将确定小胶质细胞-MyD88 是否调节突触和 PNN 的数量。 通过评估小胶质细胞的“分泌组”，PVI 和/或 PNN 相互作用间接响应慢性酒精 星形胶质细胞和 PVI 产生的 PNN 成分将决定 PVI 和/或的作用。 通过评估有或没有小胶质细胞 MyD88 的小鼠过度饮酒行为中的 PNN 相互作用 (1) 降解 PNN 和 (2) 化学遗传学抑制与小胶质细胞激活对过度饮酒的影响。 这是一个创新的新项目，旨在补充其他几个 INIA-Neuroimmune 的现有优势 如果完成，这些数据将是第一个显示小胶质细胞在 PVI/PNN 中的直接作用的数据。 的发展及其在过度饮酒中的作用，这可能会带来新的治疗选择。