PDF(Pubmed)
Abstract：
Dravet syndrome is a severe genetic epilepsy primarily caused by de novo mutations in a voltage-activated sodium channel gene (SCN1A). Patients face life-threatening seizures that are largely resistant to available anti-seizure medications. Preclinical Dravet syndrome animal models are a valuable tool to identify candidate anti-seizure medications for these patients. Among these, scn1lab mutant zebrafish, exhibiting spontaneous seizure-like activity, are particularly amenable to large-scale drug screening. Thus far, we have screened more than 3000 drug candidates in scn1lab zebrafish mutants, identifying valproate, stiripentol, and fenfluramine e.g. Food and Drug Administration-approved drugs, with clinical application in the Dravet syndrome population. Successful phenotypic screening in scn1lab mutant zebrafish is rigorous and consists of two stages: (i) a locomotion-based assay measuring high-velocity convulsive swim behaviour and (ii) an electrophysiology-based assay, using in vivo local field potential recordings, to quantify electrographic seizure-like events. Historically, nearly 90% of drug candidates fail during translation from preclinical models to the clinic. With such a high failure rate, it becomes necessary to address issues of replication and false positive identification. Leveraging our scn1lab zebrafish assays is one approach to address these problems. Here, we curated a list of nine anti-seizure drug candidates recently identified by other groups using preclinical Dravet syndrome models: 1-Ethyl-2-benzimidazolinone, AA43279, chlorzoxazone, donepezil, lisuride, mifepristone, pargyline, soticlestat and vorinostat. First-stage locomotion-based assays in scn1lab mutant zebrafish identified only 1-Ethyl-2-benzimidazolinone, chlorzoxazone and lisuride. However, second-stage local field potential recording assays did not show significant suppression of spontaneous electrographic seizure activity for any of the nine anti-seizure drug candidates. Surprisingly, soticlestat induced frank electrographic seizure-like discharges in wild-type control zebrafish. Taken together, our results failed to replicate clear anti-seizure efficacy for these drug candidates highlighting a necessity for strict scientific standards in preclinical identification of anti-seizure medications.
摘要：
Dravet综合征是一种严重的遗传性癫痫，主要由电压激活钠通道基因（SCN1A）的从头突变引起。患者面临危及生命的癫痫发作，这些癫痫发作对现有的抗癫痫药物有很大的抵抗力。临床前Dravet综合征动物模型是确定这些患者的候选抗癫痫药物的有价值的工具。其中,scn1lab突变斑马鱼,表现出自发性癫痫样活动，特别适合大规模的药物筛选。到目前为止,我们已经在scn1lab斑马鱼突变体中筛选了3000多种候选药物，鉴定丙戊酸盐，stiripentol,和芬氟拉明，例如食品和药物管理局批准的药物，在Dravet综合征人群中的临床应用。在scn1lab突变斑马鱼中成功的表型筛选是严格的，包括两个阶段：（i）基于运动的测定，测量高速惊厥游泳行为和（ii）基于电生理学的测定，使用体内局部场电位记录，量化脑电图癫痫样事件。历史上,近90%的候选药物在从临床前模型到临床的转化过程中失败.有这么高的故障率，有必要解决复制和假阳性识别的问题。利用我们的scn1lab斑马鱼分析是解决这些问题的一种方法。这里,我们使用临床前Dravet综合征模型策划了其他小组最近确定的9种抗癫痫候选药物：1-乙基-2-苯并咪唑啉酮，AA43279,氯唑沙宗,多奈哌齐,利苏立德,米非司酮,Pargyline,seticlestat和vorinostat。在scn1lab突变斑马鱼中进行的基于运动的第一阶段测定仅鉴定出1-乙基-2-苯并咪唑啉酮，氯唑沙宗和利苏利特。然而,第二阶段局部场电位记录试验未显示9种抗癫痫候选药物中任何一种对自发性电图癫痫发作活性的显著抑制.令人惊讶的是,seticlestat在野生型对照斑马鱼中诱导了坦率的电子癫痫样放电。一起来看,我们的结果未能复制这些候选药物的明确抗惊厥疗效,这凸显了在抗惊厥药物的临床前鉴定中需要严格的科学标准.
