A non-protected larval zebrafish model for the investigation of novel strategies to protect against nerve agent-induced toxicity and seizures

用于研究防止神经毒剂引起的毒性和癫痫发作的新策略的无保护幼虫斑马鱼模型

• 批准号: NC/W00092X/2
• 负责人: Matthew Parker
• 金额: $ 3.24万
• 依托单位: University of Surrey
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2022
• 资助国家: 英国
• 起止时间: 2022 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=NC%2FW00092X%2F2
• 关键词: non; protected; larval; zebrafish; model

Nerve agents are amongst the most deadly chemicals known to man and continue to pose a significant societal threat. Nerve agents function by inhibiting chemicals in the brain that affect the nervous system. Thus, nerve agents cause seizures in the brain which can lead to severe brain damage and even death. Several drugs are used as initial treatments for nerve agent poisoning, but these are sometimes ineffective and can themselves be harmful. In addition, the greater the delay between exposure to the nerve agent and the provision of treatment, for example on the battlefield, the lower the likelihood of the effectiveness of these treatments. Consequently, new and better treatment options are needed to protect against the effects of nerve agents. Current methods used for testing new drug effectiveness for the treatment of nerve agent poisoning are largely reliant on the use of rodents. Such experiments are slow and costly, and usually involve severe procedures, such as the surgical implantation of electrodes in the brain and exposure to nerve agents. There is a requirement to develop higher throughput methods for identifying novel treatments, that are also more ethically favourable than those currently available. The non-protected 4-days post-fertilisation (dpf) larval zebrafish could prove invaluable as they have been shown to be responsive to a range of seizure-inducing drugs and can be tested quickly and easily in large numbers.Scientists from the universities of Portsmouth and Exeter will build on previous NC3Rs-funded work to transfer a non-protected larval zebrafish seizure model to Dstl, where the methods can be used to identify novel treatments for nerve agent poisoning. Dr Parker is a zebrafish behavioural expert, and will develop behavioural measures of seizures in 4dpf larvae. Many of the protocols were developed during Dr Parker's work on an NC3Rs project grant at Queen Mary, London (PI Caroline Brennan). Dr Winter is an expert in examining the brain during seizures in zebrafish using advanced imaging techniques, some of which have been developed during an ongoing NC3Rs studentship. His team will focus on developing approaches assessing seizure activity in the 4dpf zebrafish brain to understand model relevance for predicting effects in mammals. The end users at Dstl will utilise this approach for the identification and development of novel treatments for nerve agent poisoning. Dstl colleagues will promote the wider uptake of this approach, and the zebrafish as a model for assessing chemical toxicity, within the international defence research community. This approach could replace a significant number of rodents used in testing novel treatments against nerve agent toxicity, thus reducing overall rodent use by an estimated 75%. Limited rodent experiments would remain only for confirmatory purposes. Our approach could therefore prevent the yearly global use of at least 1500 rodents in these severe protocols. In addition to the direct replacement of rodents, the data generated in non- protected zebrafish larvae can also be used to refine remaining rodent studies to ensure that appropriate non-toxic doses are used. Refinement will also result from the identification and ruling out of any putative treatments with undesirable properties prior to escalation to rodent models. Dstl actively participates in a number of international research collaborations including bilateral arrangements with European countries and an important multinational agreement between the Australia, Canada, the UK and the USA, the CBR Memorandum of Understanding (MOU). Dr Kearn will use these arrangements and his position as UK lead for a predictive toxicology task under the CBR MOU to share data and methodologies from this project, champion its outputs and influence other Nations' programmes to encourage uptake of this technology.

神经毒剂是人类已知的最致命的化学物质之一，并继续构成重大的社会威胁。神经毒剂的作用是抑制大脑中影响神经系统的化学物质。因此，神经毒剂会引起大脑癫痫发作，从而导致严重的脑损伤甚至死亡。有几种药物被用作神经毒剂中毒的初步治疗方法，但这些药物有时是无效的，而且本身可能是有害的。此外，接触神经毒剂与提供治疗（例如在战场上）之间的延迟时间越长，这些治疗的有效性可能性就越低。因此，需要新的和更好的治疗方案来防止神经毒剂的影响。目前用于测试治疗神经毒剂中毒的新药有效性的方法在很大程度上依赖于啮齿动物的使用。这类实验缓慢而昂贵，而且通常涉及一些严格的程序，比如在大脑中植入电极和暴露于神经毒剂中。有必要开发更高通量的方法来识别新的治疗方法，这些方法在伦理上也比现有的方法更有利。受精后4天（dpf）无保护的斑马鱼幼虫可能被证明是无价的，因为它们已被证明对一系列诱发癫痫的药物有反应，并且可以快速方便地进行大量测试。来自朴茨茅斯大学和埃克塞特大学的科学家们将在nc3rs资助的先前工作的基础上，将一个未受保护的幼体斑马鱼癫痫模型转移到Dstl，在那里，这些方法可用于确定神经毒剂中毒的新治疗方法。帕克博士是一名斑马鱼行为专家，他将开发4dpf幼虫癫痫发作的行为测量方法。许多协议都是帕克博士在伦敦玛丽皇后学院（PI Caroline Brennan）从事NC3Rs项目资助期间制定的。温特博士是使用先进成像技术检查斑马鱼癫痫发作期间大脑的专家，其中一些技术是在NC3Rs学生期间开发的。他的团队将专注于开发评估4dpf斑马鱼大脑癫痫活动的方法，以了解预测哺乳动物影响的模型相关性。Dstl的最终用户将利用这种方法识别和开发神经毒剂中毒的新治疗方法。Dstl的同事将在国际防务研究界推广更广泛地采用这种方法，并将斑马鱼作为评估化学毒性的模型。这种方法可以取代大量用于测试神经毒剂毒性新疗法的啮齿动物，从而将啮齿动物的总体使用减少约75%。有限的啮齿动物实验将仅用于验证目的。因此，我们的方法可以在这些严格的协议中防止每年全球至少使用1500只啮齿动物。除了直接替换啮齿动物外，在未受保护的斑马鱼幼虫中产生的数据也可用于改进剩余的啮齿动物研究，以确保使用适当的无毒剂量。在升级到啮齿动物模型之前，还将通过识别和排除任何具有不良性质的假定治疗方法来进行改进。Dstl积极参与多项国际研究合作，包括与欧洲国家的双边安排，以及澳大利亚、加拿大、英国和美国之间的重要多国协议- CBR谅解备忘录（MOU）。Kearn博士将利用这些安排，以及他作为CBR谅解备忘录下预测毒理学任务英国负责人的地位，分享该项目的数据和方法，支持其产出，并影响其他国家的规划，以鼓励采用这项技术。