Laboratory for Molecular Biodiscovery, Department of Pharmaceutical and Pharmacological Sciences , KU Leuven - University of Leuven , 3000 Leuven , Belgium.
Marine Biodiscovery Centre, Department of Chemistry , University of Aberdeen , Aberdeen AB24 3UE , Scotland, United Kingdom.
ACS Chem Neurosci. 2018 Jul 18;9(7):1652-1662. doi: 10.1021/acschemneuro.8b00060. Epub 2018 Apr 19.
In search for novel antiseizure drugs (ASDs), the European FP7-funded PharmaSea project used zebrafish embryos and larvae as a drug discovery platform to screen marine natural products to identify promising antiseizure hits in vivo for further development. Within the framework of this project, seven known heterospirocyclic γ-lactams, namely, pseurotin A, pseurotin A, pseurotin F1, 11- O-methylpseurotin A, pseurotin D, azaspirofuran A, and azaspirofuran B, were isolated from the bioactive marine fungus Aspergillus fumigatus, and their antiseizure activity was evaluated in the larval zebrafish pentylenetetrazole (PTZ) seizure model. Pseurotin A and azaspirofuran A were identified as antiseizure hits, while their close chemical analogues were inactive. Besides, electrophysiological analysis from the zebrafish midbrain demonstrated that pseurotin A and azaspirofuran A also ameliorate PTZ-induced epileptiform discharges. Next, to determine whether these findings translate to mammalians, both compounds were analyzed in the mouse 6 Hz (44 mA) psychomotor seizure model. They lowered the seizure duration dose-dependently, thereby confirming their antiseizure properties and suggesting activity against drug-resistant seizures. Finally, in a thorough ADMET assessment, pseurotin A and azaspirofuran A were found to be drug-like. Based on the prominent antiseizure activity in both species and the drug-likeness, we propose pseurotin A and azaspirofuran A as lead compounds that are worth further investigation for the treatment of epileptic seizures. This study not only provides the first evidence of antiseizure activity of pseurotins and azaspirofurans, but also demonstrates the value of the zebrafish model in (marine) natural product drug discovery in general, and for ASD discovery in particular.
在寻找新型抗癫痫药物 (ASD) 的过程中，欧洲 FP7 资助的 PharmaSea 项目利用斑马鱼胚胎和幼虫作为药物发现平台，筛选海洋天然产物，以鉴定出具有体内抗癫痫作用的有前途的候选药物，进一步开发。在该项目的框架内，从生物活性海洋真菌 Aspergillus fumigatus 中分离出了七种已知的杂环螺环 γ-内酰胺，即 pseurotin A、pseurotin B、pseurotin F1、11-O-甲基 pseurotin A、pseurotin D、azaspirofuran A 和 azaspirofuran B，并在斑马鱼幼虫戊四氮 (PTZ) 惊厥模型中评估了它们的抗惊厥活性。pseurotin A 和 azaspirofuran A 被鉴定为抗惊厥有效成分，而它们的化学类似物则没有活性。此外，来自斑马鱼中脑的电生理分析表明，pseurotin A 和 azaspirofuran A 也可改善 PTZ 诱导的癫痫样放电。接下来，为了确定这些发现是否适用于哺乳动物，对这两种化合物在小鼠 6 Hz（44 mA）精神运动性惊厥模型中进行了分析。结果发现，这两种化合物均能剂量依赖性地降低惊厥持续时间，从而证实了它们的抗惊厥特性，并提示其对耐药性惊厥有作用。最后，在全面的 ADMET 评估中，pseurotin A 和 azaspirofuran A 被认为具有类药性。基于这两种化合物在两种物种中的显著抗惊厥活性和类药性，我们提出 pseurotin A 和 azaspirofuran A 作为有价值的先导化合物，值得进一步研究用于治疗癫痫发作。这项研究不仅提供了 pseurotins 和 azaspirofurans 具有抗惊厥活性的首个证据，还证明了斑马鱼模型在（海洋）天然产物药物发现中的价值，特别是在 ASD 发现方面。
