Targeting CNTF to increase adult forebrain neurogenesis

靶向 CNTF 增加成人前脑神经发生

• 批准号: 8722255
• 负责人: THEO HAGG
• 金额: $ 29.93万
• 依托单位: EAST TENNESSEE STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-09-01 至 2019-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8722255
• 关键词: Acute; Adult; Agonist; Astrocytes; Blocking Antibodies; Blood; Blood Vessels; Brain; Cell Proliferation; Cells; Ciliary Neurotrophic Factor; Clinical Trials; Data; Disease; Dopamine D2 Receptor; Extravasation; Fibrinogen; Focal Adhesion Kinase 1; Funding; Genetic; Grant; In Vitro; Inflammation; Injection of therapeutic agent; Integrin Signaling Pathway; Integrins; LIF gene; Ligand Binding; Ligands; MAPK8 gene; Malignant Neoplasms; Measures; Mediating; Middle Cerebral Artery Occlusion; Modeling; Molecular Target; Mus; Nervous system structure; Neuroglia; Neurons; Pathway interactions; Pharmaceutical Preparations; Pharmacological Treatment; Play; Production; Prosencephalon; Role; Sensorimotor functions; Signal Pathway; Stem cells; Stroke; Testing; Tissues; Transgenic Mice; Treatment Protocols; Vitronectin; Work; behavior test; in vivo; inhibitor/antagonist; injured; interest; kinase inhibitor; motor function improvement; nerve stem cell; nervous system disorder; neuroblast; neurogenesis; neuron loss; preconditioning; progenitor; public health relevance; research study; self-renewal; subventricular zone; treatment effect

DESCRIPTION (provided by applicant): Ciliary neurotrophic factor (CNTF) in the subventricular zone (SVZ) of the forebrain promotes neurogenesis in adult mice. We found that CNTF is normally repressed in the CNS by cell contact and increases greatly after stroke-induced neuron loss. This helped us to discover a new focal adhesion kinase (FAK)-JNK signaling pathway that is activated by ligand binding to DvE5 integrin in glia and potently inhibit their CNTF expression. Importantly, systemic treatment with pharmacological FAK inhibitors stimulates SVZ CNTF and neurogenesis. Our data show that stroke-induced neurogenesis is mediated entirely by stroke-induced CNTF, which may be counteracted by stroke-induced LIF and inflammation over the first week. In vitro, vitronectin represses CNTF and stimulates LIF, perhaps representing a vascular-derived regulator of neurogenesis. Here we will define these pathways in vivo, using a combination of available transgenic mice and pharmacological drugs in adult mice. Specifically, Aim 1a will determine whether vitronectin represses CNTF expression through the DvE5 integrin-FAK pathway in SVZ astrocytes under normal conditions. This will be done by intracerebral rescue experiments in vitronectin-/- mice, injecting integrin blocking antibodies against Dv and E5 integrin subunits, using E5 integrin-/- and inducible astroglial FAK-/- mice and defining effects on progenitors vs. neural stem cells (NSCs). Aim 1b will test whether this is mediated by JNK and/or other pathways, using intracerebral injections of pharmacological inhibitors and JNK-/- mice, while measuring effects on CNTF expression and neurogenesis. Aim 2a will determine whether stroke-induced leakage of blood-derived vitronectin causes increased LIF expression to stimulate NSC self-renewal. This will be done in a middle cerebral artery occlusion (MCAO) model by i.v. injections of vitronectin in vitronectin-/- mice. Aim 2b will determine whether the same integrin-FAK pathways play a role after MCAO, and whether CNTF and LIF can be regulated by FAK inhibitors. Aim 2c will define whether LIF is involved in repressing neurogenesis or is preconditioning the SVZ for later CNTF-induced neurogenesis. Aim 3a. Wwill test whether systemic FAK inhibitor treatment is more effective in inducing SVZ CNTF and neurogenesis when started after inflammation has resolved following MCAO, or Aim 3b when given intermittently. FAK acts via a different mechanism than the D2 dopamine receptor, which we showed increases SVZ neurogenesis by increasing astroglial CNTF. Therefore, Aim 3c will combine FAK inhibitor and D2 agonist to maximize CNTF expression and neurogenesis after MCAO, and determine whether this allows more new neurons to populate the injured tissue. The potential effects of these treatments on sensorimotor function will be assessed by behavioral tests.

描述（由申请人提供）：前脑室下区（SVZ）中的睫状神经营养因子（CNTF）促进成年小鼠的神经发生。我们发现 CNTF 通常在中枢神经系统中通过细胞接触受到抑制，并在中风引起的神经元损失后大大增加。这帮助我们发现了一种新的粘着斑激酶 (FAK)-JNK 信号通路，该通路通过配体与神经胶质细胞中的 DvE5 整合素结合而激活，并有效抑制其 CNTF 表达。重要的是，药物 FAK 抑制剂的全身治疗可刺激 SVZ CNTF 和神经发生。我们的数据表明，中风诱发的神经发生完全由中风诱发的 CNTF 介导，这可能会在第一周内被中风诱发的 LIF 和炎症所抵消。在体外，玻连蛋白抑制 CNTF 并刺激 LIF，可能代表神经发生的血管源性调节剂。在这里，我们将结合使用现有的转基因小鼠和成年小鼠的药理学药物，在体内定义这些途径。具体而言，目标 1a 将确定正常条件下玻连蛋白是否通过 DvE5 整合素-FAK 途径抑制 SVZ 星形胶质细胞中的 CNTF 表达。这将通过在玻连蛋白-/-小鼠中进行脑内拯救实验来完成，注射针对Dv和E5整合素亚基的整合素阻断抗体，使用E5整合素-/-和诱导型星形胶质细胞FAK-/-小鼠，并确定对祖细胞与神经干细胞（NSC）的影响。目标 1b 将使用药物抑制剂和 JNK-/- 小鼠脑内注射来测试这是否是由 JNK 和/或其他途径介导的，同时测量对 CNTF 表达和神经发生的影响。目标 2a 将确定中风引起的血源性玻连蛋白渗漏是否会导致 LIF 表达增加，从而刺激 NSC 自我更新。这将通过静脉注射在大脑中动脉闭塞 (MCAO) 模型中完成。注射玻连蛋白 玻连蛋白-/- 老鼠。目标 2b 将确定相同的整合素-FAK 途径是否在 MCAO 后发挥作用，以及 CNTF 和 LIF 是否可以受到 FAK 抑制剂的调节。目标 2c 将定义 LIF 是否参与抑制神经发生或为随后 CNTF 诱导的神经发生预处理 SVZ。目标 3a。我们将测试 MCAO 后炎症消退后开始全身性 FAK 抑制剂治疗是否能更有效地诱导 SVZ CNTF 和神经发生，或间歇性给予 Aim 3b。 FAK 通过与 D2 多巴胺受体不同的机制发挥作用，我们发现 FAK 通过增加星形胶质细胞 CNTF 来增加 SVZ 神经发生。因此，Aim 3c 将结合 FAK 抑制剂和 D2 激动剂，以最大限度地提高 MCAO 后的 CNTF 表达和神经发生，并确定这是否允许更多新神经元填充受损组织。这些治疗对感觉运动功能的潜在影响将通过行为测试进行评估。