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/1
• 负责人: Matthew Parker
• 金额: $ 8.1万
• 依托单位: University of Portsmouth
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2021
• 资助国家: 英国
• 起止时间: 2021 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=NC%2FW00092X%2F1
• 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。神经剂通过抑制影响神经系统的大脑中的化学物质来发挥作用。因此，神经剂会导致大脑癫痫发作，从而导致严重的大脑损伤甚至死亡。几种药物被用作神经毒剂中毒的初始治疗方法，但有时是无效的，自身可能是有害的。此外，暴露于神经剂和提供治疗之间的延迟越大，例如在战场上，这些治疗的有效性的可能性就越高。因此，需要新的更好的治疗选择来防止神经毒剂的作用。用于测试用于治疗神经毒剂中毒的新药物有效性的当前方法主要依赖于啮齿动物的使用。这样的实验缓慢且昂贵，通常涉及严重的程序，例如大脑中电极的手术植入和暴露于神经药物。需要开发更高的吞吐量方法来识别新型治疗方法，这些方法在道德上也比当前可用的疗法更有利。未受保护的四日施肥（DPF）幼虫斑马鱼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发作的药物有响应，可以在大量的港口和埃克斯特大学中迅速而轻松地进行测试。 DSTL，可以使用这些方法来识别神经毒剂中毒的新型治疗方法。帕克博士是斑马鱼行为专家，将在4DPF幼虫中发展癫痫发作的行为指标。帕克博士在伦敦皇后（Pi Caroline Brennan）的NC3RS项目赠款的工作中开发了许多协议。 Winter博士是使用先进的成像技术在斑马鱼癫痫发作期间检查大脑的专家，其中一些是在正在进行的NC3RS学生中开发的。他的团队将专注于开发评估4DPF斑马鱼大脑中癫痫发作活动的方法，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来识别和开发神经毒剂中毒的新型治疗方法。 DSTL同事将促进这种方法的更广泛的吸收，而斑马鱼则是评估化学毒性的模型，在国际国防研究界内。这种方法可以替代用于测试针对神经毒剂毒性的新型治疗方法的大量啮齿动物，从而将总啮齿动物的使用量降低了估计的75％。有限的啮齿动物实验仅用于确认目的。因此，我们的方法可以防止在这些严重的方案中每年至少使用1500个啮齿动物的全球使用。除了直接替代啮齿动物外，在非受保护的斑马鱼幼虫中产生的数据也可用于完善剩余的啮齿动物研究，以确保使用适当的无毒剂量。精炼还将源于任何假定处理的识别和排除，并在升级为啮齿动物模型之前具有不良特性。 DSTL积极参与许多国际研究合作，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跨国协议，CBR谅解备忘录（MOU）。 Kearn博士将利用这些安排，并将其作为CBR MOU下一项预测毒理学任务的英国领导地位共享该项目的数据和方法，倡导其产出并影响其他国家的计划，以鼓励采用这项技术。