Department of Environmental and Molecular Toxicology, Environmental Health Sciences Center, Sinnhuber Aquatic Research Laboratory, Oregon State University, Corvallis, OR 97333, United States.
Toxicol Appl Pharmacol. 2018 Apr 1;344:23-34. doi: 10.1016/j.taap.2018.02.019. Epub 2018 Feb 27.
The comparative analysis of complex behavioral phenotypes is valuable as a reductionist tool for both drug discovery and defining chemical bioactivity. Flavonoids are a diverse class of chemicals that elicit robust neuroactive and hormonal actions, though bioactivity information is limited for many, particularly for neurobehavioral endpoints. Here, we used a zebrafish larval chemomotor response (LCR) bioassay to comparatively evaluate a suite of 24 flavonoids, and in addition a panel of 30 model neuroactive compounds representing diverse modes of action (e.g. caffeine, chlorpyrifos, methamphetamine, nicotine, picrotoxin). Naïve larval zebrafish were exposed to concentration ranges of each compound at 120 hour post-fertilization (hpf) and locomotor activity measured for 5 h. The model neuroactive compounds were largely behaviorally bioactive (20 of 30) with most effects phenotypic of their known modes of action. Flavonoids rapidly and broadly elicited hyperactive locomotor effects (22 of 24). Multidimensional analyses compared responses over time and identified three distinct bioactive groups of flavonoids based on efficacy and potency. Using GABAergics to modulate hyperactive responses, two flavonoids, (S)-equol and kaempferol were tested for GABA receptor antagonism, as well as a known GABA receptor antagonist, picrotoxin. Pharmacological intervention with positive allosteric modulators of the GABA receptor, alfaxalone and chlormethiazole, ameliorated the hyperactive response to picrotoxin, but not for (S)-equol or kaempferol. Taken together, these studies demonstrate that flavonoids are differentially bioactive and that the chemobehavioral effects likely do not involve a GABA receptor mediated mode of action. Overall, the integrative zebrafish platform provides a useful framework for comparatively evaluating high-content chemobehavioral data for sets of structurally- and mechanistically-related flavonoids and neuroactive compounds.
复杂行为表型的比较分析是一种有用的简化工具，可用于药物发现和定义化学生物活性。类黄酮是一类多样化的化学物质，它们会引起强烈的神经活性和激素作用，尽管许多类黄酮的生物活性信息有限，特别是对于神经行为终点。在这里，我们使用斑马鱼幼虫趋化反应（LCR）生物测定法来比较评估了 24 种类黄酮，以及代表不同作用模式的 30 种模型神经活性化合物的组，例如咖啡因、毒死蜱、甲基苯丙胺、尼古丁、胡椒碱。在受精后 120 小时（hpf），将幼稚的斑马鱼幼虫暴露于每种化合物的浓度范围内，并在 5 小时内测量运动活性。大多数模型神经活性化合物具有行为生物活性（30 种中的 20 种），大多数作用与已知作用模式一致。类黄酮迅速而广泛地引起了过度活跃的运动效应（24 种中的 22 种）。多维分析比较了随时间的响应，并根据功效和效力确定了基于类黄酮的三个不同的生物活性组。使用 GABA 能药物来调节过度活跃的反应，我们测试了两种类黄酮（S）-equol 和山奈酚的 GABA 受体拮抗作用，以及一种已知的 GABA 受体拮抗剂胡椒碱。GABA 受体的正变构调节剂的药理干预，如 alfaxalone 和氯美噻唑，改善了对胡椒碱的过度活跃反应，但对（S）-equol 或山奈酚没有改善作用。总之，这些研究表明类黄酮具有不同的生物活性，并且化学行为效应可能不涉及 GABA 受体介导的作用模式。总的来说，整合的斑马鱼平台为比较评估结构和机制相关的类黄酮和神经活性化合物的高内涵化学行为数据提供了一个有用的框架。
