Project 2: Advancing glyoxylate as a chemical countermeasure

尽管存在几种具有氰化物解毒活性的化合物，但它们都是通过化学计量反应起作用的 与游离氰化物形成毒性较小的氰化物络合物。因此，这些氰化物清道夫只在 化学计量剂量，只有在氰化物与其目标蛋白相互作用之前。一种氰化物对策 这不是仅仅依靠清除游离氰化物将是一个非常有价值的补充 对策武器库，因为它可能1)在亚化学计量剂量下有效，2)用于 与现有的清除剂相结合，以及3)即使在氰化物与其结合后也能提供好处 细胞目标。我们财团最近的发现工作已经确定乙醛是一种有效的和高度 有效的氰化物防护剂。乙醛治疗拯救斑马鱼，小鼠和兔子暴露在 氰化物。值得注意的是，乙醛似乎不仅仅是氰化物的清除剂。相反，它 似乎产生了一种快速而戏剧性的代谢变化，使几种关键的代谢正常化 氰化物引起的紊乱，包括耗氧量、代谢产物通量和氧化还原的扰动 平衡。因此，乙醛似乎通过一种与现有的非常不同的机制发挥作用 基于清道夫的氰化物对策。因此，它可以补充现有的对策和 提供了一种全新的方法来逆转氰化物的影响。 在这个项目中，我们将重点提供一种或多种乙醛基对抗性产品。 工作将包括优化乙醛基衍生物用作氰化物解毒剂通过标准 制定和优化策略。我们还将探索乳酸脱氢酶，假定乙醛的目标，作为一种 第二代氰化物解毒剂的潜在来源。最后，我们将测试乙醛的解救能力 其他代谢毒物，硫化物和叠氮化物的影响。具体目标包括： 目的1.优化乙醛酸盐作为临床应用的对策。这一目标侧重于 乙醛的配方，以产生稳定的对策产品，可以通过自动注射器输送。 目的2.开发替代的乳酸脱氢酶底物作为第二代乙醛酸样对策。 目的是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。 目的3.测试乙醛作为对抗其他代谢毒物的方法。这一目标考验的是 乙醛可逆转包括硫化物和叠氮化物在内的其他代谢毒物的毒性作用。 该项目的成功完成将提供至少一种经过充分验证的乙醛基氰化物 符合BARDA高级发展要求的对策。它还将填补这条管道 利用代谢调节来中和氰化物毒性的第二代对策。 。

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. .