Project 2: Advancing glyoxylate as a chemical countermeasure

虽然存在几种具有氰化物解毒活性的化合物，但所有化合物均通过化学计量反应发挥作用 与游离氰化物形成毒性较低的氰化物络合物。因此，这些氰化物清除剂只在 化学计量剂量，并且仅在氰化物与其靶蛋白相互作用之前。氰化物对策 不完全依赖于清除游离氰化物的方法将是一个非常有价值的补充， 对抗武器库，因为它可能1）在亚化学计量剂量下有效，2）用于 与现有的清除剂组合，以及3）即使在氰化物结合到其上之后也提供益处。 细胞目标。我们联盟内最近的发现工作已经确定乙醛酸是一种有效的高度 有效的氰化物对策。乙醛酸盐治疗可拯救暴露于环境中的斑马鱼、小鼠和兔子 氰化物值得注意的是，乙醛酸似乎不仅仅是作为氰化物清除剂。而是 似乎产生了一个快速和戏剧性的代谢转化，使几个关键的代谢正常化， 氰化物引起的紊乱，包括耗氧量、代谢物通量和氧化还原的扰动 平衡因此，乙醛酸盐似乎通过与现有技术非常不同的机制起作用。 清除剂氰化物对策。因此，它可以补充现有的反措施， 提供了一种全新的方法来逆转氰化物的影响。 在本项目中，我们将专注于提供一种或多种基于乙醛酸盐的对策产品。 努力将包括优化乙醛酸酯衍生物，通过标准化， 制定和优化策略。我们还将探讨LDH，假定乙醛酸目标，作为一个 第二代氰化物解毒剂的潜在来源最后，我们将测试乙醛酸的救援能力， 其他代谢毒物硫化物和叠氮化物的影响。具体目标包括： 目标1。优化乙醛酸作为临床部署的对策。这一目标的重点是 本发明涉及乙醛酸盐制剂以产生可通过自动注射器递送的稳定对策产物。 目标二。开发替代LDH底物作为第二代乙醛酸盐样对策。 本研究旨在通过研究探索一系列替代LDH底物作为潜在的氰化物对策 在斑马鱼、老鼠和兔子身上。 目标3。检测乙醛酸作为其他代谢毒物的对抗措施。这一目标考验着 乙醛酸酯的毒性作用，以扭转其他代谢毒物，包括硫化物和叠氮化物。 该项目的成功完成将提供至少一个完全验证的，乙醛酸基氰化物 满足巴尔达高级开发要求的对策。它也将填补管道 第二代对策是利用代谢调节来抵消氰化物毒性。 .

Although several compounds with cyanide antidote activity exist, all function via stoichiometric reaction with free cyanide to form a less-toxic cyanide complex. As such, these cyanide scavengers only work at stoichiometric doses and only prior to cyanide interacting with its target proteins. A cyanide countermeasure that did not rely solely on scavenging of free cyanide would be a highly-valuable addition to the countermeasure arsenal because it could potentially 1) be effective at sub-stoichiometric doses, 2) be used in combination with existing scavenging agents, and 3) provide benefit even after cyanide had bound to its cellular targets. Recent discovery efforts within our consortium have identified glyoxylate as a potent and highly effective cyanide countermeasure. Treatment with glyoxylate rescues zebrafish, mice, and rabbits exposed to cyanide. Remarkably, glyoxylate does not appear to be functioning only as a cyanide scavenger. Rather, it appears to produce a rapid and dramatic metabolic transformation that normalizes several key metabolic derangements induced by cyanide, including perturbations in oxygen consumption, metabolite flux, and redox balance. Thus, glyoxylate appears to function through a mechanism that is very different from existing scavenger-based cyanide countermeasures. As such, it may complement existing countermeasures and provide a completely novel means of reversing cyanide's effects. In this project we will focus on delivering one or more glyoxylate-based countermeasure products. Efforts will include optimization of glyoxylate derivatives for use as cyanide antidotes through standard formulation and optimization strategies. We will also explore LDH, the presumptive glyoxylate target, as a potential source of second-generation cyanide antidotes. Finally, we will test the ability of glyoxylate to rescue the effects of other metabolic poisons, sulfide and azide. Specific aims include: Aim 1. To optimize glyoxylate as a countermeasure for clinical deployment. This aim focuses on formulation of glyoxylate to produce a stable countermeasure product that can be delivered by autoinjector. Aim 2. To develop alternative LDH substrates as second-generation, glyoxylate-like countermeasures. This aim explores a series of alternative LDH substrates as potential cyanide countermeasures through studies in zebrafish, mice, and rabbits. Aim 3. To test glyoxylate as a countermeasure for other metabolic poisons. This aim tests the ability of glyoxylate to reverse the toxic effects of other metabolic poisons including sulfide and azide. Successful completion of this project will deliver at least one fully validated, glyoxylate-based cyanide countermeasure that meets the BARDA requirements for advanced development. It will also fill the pipeline with second-generation countermeasures that exploit metabolic modulation to counteract cyanide toxicity. .