Novel neurotrophic therapies in an optimized mouse model of GWVI

优化的 GWVI 小鼠模型中的新型神经营养疗法

• 批准号: 8974377
• 负责人: ALPASLAN DEDEOGLU
• 金额: --
• 依托单位: VA BOSTON HEALTH CARE SYSTEM
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-07-01 至 2018-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8974377
• 关键词: Acetylcholinesterase; Acetylcholinesterase Inhibitors; Agonist; Alzheimer' s Disease; Amyotrophic Lateral Sclerosis; Animal Model; Animals; Arthralgia; Attention; Autonomic nervous system; Axotomy; Behavior; Behavioral; Behavioral Symptoms; Biology; Blood - brain barrier anatomy; Brain; Brain Stem; Brain-Derived Neurotrophic Factor; Bromides; Cell Culture Techniques; Cells; Chemical Warfare; Chronic; Cognitive; Data; Defect; Disease; Dose; Drug Combinations; Drug Design; Drug Targeting; Environment; Etiology; Evaluation; Exercise; Exposure to; Fatigue; Fluorescence-Activated Cell Sorting; Functional disorder; Future; Gene Expression Profiling; Genes; Goals; Green Fluorescent Proteins; Gulf War; Headache; Health; Hippocampus (Brain); Human; Human Resources; Imagery; Imaging Techniques; Impaired cognition; Insect Repellents; Insecta; Insecticides; Magnetic Resonance Imaging; Magnetic Resonance Spectroscopy; Measurement; Mediating; Memory; Military Personnel; Modality; Modeling; Moderate Exercise; Mus; Myalgia; Nervous system structure; Neuraxis; Neurons; Neurotrophic Tyrosine Kinase Receptor Type 2; Outcome Measure; Parkinson Disease; Patients; Permethrin; Pharmaceutical Preparations; Physiological; Post-Traumatic Stress Disorders; Rattus; Recovery; Regimen; Reporting; Rett Syndrome; Role; Sarin; Signal Transduction; Skin Abnormalities; Sleep; Sleep disturbances; Sodium Channel; Stress; Symptoms; Synapses; Synaptic plasticity; System; Techniques; Telemetry; Testing; Therapeutic; Toxin; Transgenic Mice; Veterans; basal forebrain cholinergic neurons; behavioral pharmacology; cerebral blood volume; cholinergic; cholinergic neuron; design; exercise intervention; gastrointestinal; in vivo; memory process; microscopic imaging; mouse model; nerve agent; neurochemistry; neurogenesis; novel; nucleus ambiguus; postnatal; prevent; public health relevance; pyridostigmine; receptor; restraint stress; septohippocampal; spatial memory; success; therapy design; treatment response

DESCRIPTION (provided by applicant): The etiology and pathophysiology of Gulf War Veterans' Illness (GWVI) remain poorly understood and treatments are lacking. Most studies suggest that GWVI may be the result of exposure to drugs designed to protect military personnel from a chemical warfare attack and from insects. These drugs include: 1) pyridostigmine bromide (PB) - a reversible inhibitor of acetylcholinesterase (AChE) - that prevents nerve agents, such as sarin, from inhibiting AChE permanently; 2) permethrin (PET) - an insecticide whose mechanism of action is to block neuronal sodium channels; and 3) DEET - an insect repellent. These drugs target the nervous system and in particular, via the inhibition of AChE, the cholinergic system. Although these drugs are safe at the doses given to GW personnel, it has been hypothesized that their combination together with the stress encountered during the GW deployment may have contributed collectively to generate the multi-symptom disease, GWVI. This has been tested in toxin/stress animal models with considerable success. Recent landmark studies performed on GW Veterans and non-deployed Veterans indicate that pathophysiology of GWVI involves abnormalities in the function of the cholinergic parasympathetic system. Moreover, cognitive and sleep disturbances that characterize GWVI are consistent with a dysfunction of the basal forebrain cholinergic neurons (BFCN) whose normal activity is central to the processes of memory, attention and sleep. Together the data point to the possibility that the GW-associated exposure to the above-listed drugs and to stress caused a long-term dysfunction of cholinergic neurons within central nervous system (CNS). Therefore it would be desirable to design treatment modalities that could restore the normal functioning of cholinergic neurons and their targets in patients with GWVI. One strategy to accomplish this goal would be to use trophic factors that support neuronal viability and function. Specifically brain derived neurotrophic facto (BDNF) that signals via its receptor, TrkB. The central parasympathetic neurons and BFCN express TrkB. BDNF increases BFCN survival and elevates their cholinergic marker expression in cell culture and it is necessary for postnatal maturation of BFCN in vivo. BDNF prevents axotomy-induced degeneration and loss of cholinergic marker expression in BFCN in rats. However, BDNF does not cross the blood-brain barrier (BBB). 7,8-dihydroxyflavone (7,8-DHF) is a potent and selective TrkB agonist that readily enters the brain. Beneficial effects of 7,8-DHF have been reported in models of PTSD, PD, AD and Rett syndrome. We found that 7,8-DHF is effective in mouse models of ALS and AD. The overall goal of the proposed studies is to test the hypothesis that administration of 7,8-DHF and/or moderate exercise (MEX) - interventions known to generate a trophic neuronal environment - will cause a recovery of brain function in a mouse model of GWVI optimized for the studies of cholinergic neurons. Specifically, we will use the CHGFP transgenic mouse line that expresses the green fluorescent protein (GFP) exclusively in cholinergic cells. This permits the purification of these cells by fluorescence-activated cell sorting (FACS) and facilitates their visualization with microscopic imaging techniques. These mice will be exposed to the GWVI- associated drug combination (PB/PET/DEET) together with restraint stress, and then to our therapeutic regimens (i.e. 7,8-DHF and/or MEX) that will be employed immediately after the exposure, or after a delay of 4 weeks to treat an established illness. These studies incorporate principles of rational pharmacology and behavioral evaluation combined with state-of- the-art MR imaging and spectroscopy, physiological telemetry as well as neuropathological, neurochemical and gene-analytic techniques to define the therapeutic benefits of a novel neurotrophic compound that crosses the BBB as well as a non-pharmacological treatment modality in a unique GWVI mouse model. In addition, our studies will contribute to our understanding of the basic biology of cholinergic neurons and their role in GWVI and further characterize a novel animal model for future use to test therapeutics relevant to patients with GWVI.

描述（由申请人提供）： 海湾战争退伍军人病 (GWVI) 的病因和病理生理学仍然知之甚少，并且缺乏治疗方法。大多数研究表明，GWVI 可能是接触旨在保护军事人员免受化学战攻击和昆虫侵害的药物的结果。这些药物包括： 1) 溴吡斯的明 (PB) - 一种乙酰胆碱酯酶 (AChE) 的可逆抑制剂 - 可防止沙林等神经毒剂永久抑制 AChE； 2）氯菊酯（PET）——一种杀虫剂，其作用机制是阻断神经元钠通道； 3) DEET——驱虫剂。这些药物针对神经系统，特别是通过抑制 AChE（胆碱能系统）。尽管这些药物在给予 GW 人员的剂量下是安全的，但据推测，它们的组合加上 GW 部署期间遇到的压力可能共同导致了多症状疾病 GWVI。这已在毒素/应激动物模型中进行了测试，并取得了相当大的成功。最近对 GW 退伍军人和非服役退伍军人进行的里程碑式研究表明，GWVI 的病理生理学涉及胆碱能副交感神经系统功能异常。此外，以 GWVI 为特征的认知和睡眠障碍与基底前脑胆碱能神经元 (BFCN) 的功能障碍一致，基底前脑胆碱能神经元的正常活动对于记忆、注意力和睡眠过程至关重要。这些数据共同表明，与 GW 相关的上述药物暴露和压力可能导致中枢神经系统 (CNS) 内胆碱能神经元的长期功能障碍。因此，需要设计能够恢复 GWVI 患者胆碱能神经元及其靶标正常功能的治疗方式。实现这一目标的一种策略是使用支持神经元活力和功能的营养因子。具体来说，脑源性神经营养因子 (BDNF) 通过其受体 TrkB 发出信号。中枢副交感神经元和 BFCN 表达 TrkB。 BDNF 可增加 BFCN 的存活率并提高其在细胞培养物中的胆碱能标志物表达，并且对于 BFCN 在体内的出生后成熟是必需的。 BDNF 可防止大鼠 BFCN 中轴索切断术引起的变性和胆碱能标志物表达的丧失。然而，BDNF 不能穿过血脑屏障 (BBB)。 7,8-二羟基黄酮 (7,8-DHF) 是一种有效的选择性 TrkB 激动剂，很容易进入大脑。 7,8-DHF 的有益作用 在 PTSD、PD、AD 和 Rett 综合征模型中已有报道。我们发现 7,8-DHF 对 ALS 和 AD 小鼠模型有效。拟议研究的总体目标是检验以下假设：施用 7,8-DHF 和/或适度运动 (MEX)（已知可产生营养神经元环境的干预措施）将导致小鼠模型中大脑功能的恢复。 GWVI 针对胆碱能神经元的研究进行了优化。具体来说，我们将使用仅在胆碱能细胞中表达绿色荧光蛋白（GFP）的 CHGFP 转基因小鼠系。这允许通过荧光激活细胞分选（FACS）来纯化这些细胞，并促进它们通过显微成像技术的可视化。这些小鼠将接受 GWVI 相关药物组合 (PB/PET/DEET) 以及约束应激，然后接受我们的治疗方案（即 7,8-DHF 和/或 MEX），该方案将在暴露后立即采用，或延迟 4 周后治疗既定疾病。这些研究结合了合理药理学和行为评估的原理，结合最先进的磁共振成像和光谱学、生理遥测以及神经病理学、神经化学和基因分析技术，以确定一种跨领域的新型神经营养化合物的治疗益处。 BBB 以及独特的 GWVI 小鼠模型中的非药物治疗方式。此外，我们的研究将有助于我们了解胆碱能神经元的基本生物学及其在 GWVI 中的作用，并进一步表征一种新型动物模型，以供将来用于测试与 GWVI 患者相关的治疗方法。