title: Clemizole and modulators of serotonin signalling suppress seizures in Dravet syndrome.
abstract: Dravet syndrome is a catastrophic childhood epilepsy with early-onset seizures, delayed language and motor development, sleep disturbances, anxiety-like behaviour, severe cognitive deficit and an increased risk of fatality. It is primarily caused by de novo mutations of the SCN1A gene encoding a neuronal voltage-activated sodium channel. Zebrafish with a mutation in the SCN1A homologue recapitulate spontaneous seizure activity and mimic the convulsive behavioural movements observed in Dravet syndrome. Here, we show that phenotypic screening of drug libraries in zebrafish scn1 mutants rapidly and successfully identifies new therapeutics. We demonstrate that clemizole binds to serotonin receptors and its antiepileptic activity can be mimicked by drugs acting on serotonin signalling pathways e.g. trazodone and lorcaserin. Coincident with these zebrafish findings, we treated five medically intractable Dravet syndrome patients with a clinically-approved serotonin receptor agonist (lorcaserin, Belviq®) and observed some promising results in terms of reductions in seizure frequency and/or severity. Our findings demonstrate a rapid path from preclinical discovery in zebrafish, through target identification, to potential clinical treatments for Dravet syndrome.
authors.affiliation: Epilepsy Research Laboratory and Weill Institute for Neurosciences, Department of Neurological Surgery, University of California, San Francisco, San Francisco, CA, USA.
authors.forename: Aliesha
authors.initials: A
authors.lastname: Griffin
authors.affiliation: Epilepsy Research Laboratory and Weill Institute for Neurosciences, Department of Neurological Surgery, University of California, San Francisco, San Francisco, CA, USA.
authors.forename: Kyla R
authors.initials: KR
authors.lastname: Hamling
authors.affiliation: Department of Pediatrics, University of Colorado Denver, Denver, CO, USA.
authors.forename: Kelly
authors.initials: K
authors.lastname: Knupp
authors.affiliation: Departments of Bioengineering, Electrical Engineering and Computer Science, and Biophysics Program, University of California, Berkeley, Berkeley, CA, USA.
authors.forename: SoonGweon
authors.initials: S
authors.lastname: Hong
authors.affiliation: Departments of Bioengineering, Electrical Engineering and Computer Science, and Biophysics Program, University of California, Berkeley, Berkeley, CA, USA.
authors.forename: Luke P
authors.initials: LP
authors.lastname: Lee
authors.affiliation: Epilepsy Research Laboratory and Weill Institute for Neurosciences, Department of Neurological Surgery, University of California, San Francisco, San Francisco, CA, USA.
authors.forename: Scott C
authors.initials: SC
authors.lastname: Baraban
mesh_terms: D000293:Adolescent; D000818:Animals; D030801:Animals, Genetically Modified; D000927:Anticonvulsants / Q000494:pharmacology / Q000627:therapeutic use*; D001552:Benzazepines / Q000494:pharmacology / Q000627:therapeutic use; D001562:Benzimidazoles / Q000494:pharmacology / Q000627:therapeutic use*; D002648:Child; D004195:Disease Models, Animal; D004831:Epilepsies, Myoclonic / Q000150:complications / Q000188:drug therapy* / Q000235:genetics / Q000378:metabolism; D005260:Female; D018507:Gene Expression Regulation, Developmental / Q000187:drug effects / Q000235:genetics; D006801:Humans; D007814:Larva; D008297:Male; D062550:NAV1.1 Voltage-Gated Sodium Channel / Q000235:genetics; D011485:Protein Binding / Q000187:drug effects / Q000235:genetics; D011985:Receptors, Serotonin / Q000378:metabolism; D012640:Seizures / Q000188:drug therapy* / Q000209:etiology; D012701:Serotonin / Q000378:metabolism*; D015398:Signal Transduction / Q000187:drug effects* / Q000235:genetics; D016896:Treatment Outcome; D015027:Zebrafish
chemical_list: D000927:Anticonvulsants; D001552:Benzazepines; D001562:Benzimidazoles; D062550:NAV1.1 Voltage-Gated Sodium Channel; D011985:Receptors, Serotonin; D012701:Serotonin; C506658:lorcaserin; C084582:clemizole
keywords: drug-screening; epilepsy; personalized medicine; serotonin; zebrafish