Scientific publications

Epilepsy and neuropsychiatric comorbidities in mice carrying a recurrent Dravet syndrome SCN1A missense mutation

Oct 2, 2019 | Magazine: Scientific Reports

Ana Ricobaraza, Lucia Mora-Jimenez, Elena Puerta, Rocio Sanchez-Carpintero, Ana Mingorance, Julio Artieda, Maria Jesus Nicolas, Guillermo Besne, Maria Bunuales, Manuela Gonzalez-Aparicio, Noemi Sola-Sevilla, Miguel Valencia, Ruben Hernandez-Alcoceba


Abstract

Dravet Syndrome (DS) is an encephalopathy with epilepsy associated with multiple neuropsychiatric comorbidities. In up to 90% of cases, it is caused by functional happloinsufficiency of the SCN1A gene, which encodes the alpha subunit of a voltage-dependent sodium channel (Nav1.1). Preclinical development of new targeted therapies requires accessible animal models which recapitulate the disease at the genetic and clinical levels.

Here we describe that a C57BL/6 J knock-in mouse strain carrying a heterozygous, clinically relevant SCN1A mutation (A1783V) presents a full spectrum of DS manifestations. This includes 70% mortality rate during the first 8 weeks of age, reduced threshold for heat-induced seizures (4.7 °C lower compared with control littermates), cognitive impairment, motor disturbances, anxiety, hyperactive behavior and defects in the interaction with the environment. In contrast, sociability was relatively preserved.

Electrophysiological studies showed spontaneous interictal epileptiform discharges, which increased in a temperature-dependent manner. Seizures were multifocal, with different origins within and across individuals. They showed intra/inter-hemispheric propagation and often resulted in generalized tonic-clonic seizures. 18F-labelled flourodeoxyglucose positron emission tomography (FDG-PET) revealed a global increase in glucose uptake in the brain of Scn1aWT/A1783V mice. We conclude that the Scn1aWT/A1783V model is a robust research platform for the evaluation of new therapies against DS.

CITATION  Sci Rep. 2019 Oct 2;9(1):14172. doi: 10.1038/s41598-019-50627-w.

Our authors

Ana Lourdes Ricobaraza Abarquero
Mª Jesus Nicolás Apesteguía
Laboratory technician Parkinson's Disease Research Group
Silueta investigador
Guillermo Besné Villanueva
María Buñuales Aramendía
Manuela González Aparicio
Miguel Valencia Ustárroz