Electroclinical characterization of epileptic seizures in leucine-rich, glioma-inactivated 1-deficient mice.
Mutations of the LGI1 (leucine-rich, glioma-inactivated 1) gene underlie autosomal dominant lateral temporal lobe epilepsy, a focal idiopathic inherited epilepsy syndrome. The LGI1 gene encodes a protein secreted by neurons, one of the only non-ion channel genes implicated in idiopathic familial epilepsy. While mutations probably result in a loss of function, the role of LGI1 in the pathophysiology of epilepsy remains unclear. Here we generated a germline knockout mouse for LGI1 and examined spontaneous seizure characteristics, changes in threshold for induced seizures and hippocampal pathology. Frequent spontaneous seizures emerged in homozygous LGI1(-/-) mice during the second postnatal week. Properties of these spontaneous events were examined in a simultaneous video and intracranial electroencephalographic recording. Their mean duration was 120 +/- 12 s, and behavioural correlates consisted of an initial immobility, automatisms, sometimes followed by wild running and tonic and/or clonic movements. Electroencephalographic monitoring indicated that seizures originated earlier in the hippocampus than in the cortex. LGI1(-/-) mice did not survive beyond postnatal day 20, probably due to seizures and failure to feed. While no major developmental abnormalities were observed, after recurrent seizures we detected neuronal loss, mossy fibre sprouting, astrocyte reactivity and granule cell dispersion in the hippocampus of LGI1(-/-) mice. In contrast, heterozygous LGI1(+/-) littermates displayed no spontaneous behavioural epileptic seizures, but auditory stimuli induced seizures at a lower threshold, reflecting the human pathology of sound-triggered seizures in some patients. We conclude that LGI1(+/-) and LGI1(-/-) mice may provide useful models for lateral temporal lobe epilepsy, and more generally idiopathic focal epilepsy.
Chabrol
Elodie
E
CRICM UMR_S975, Hôpital de la Pitié-Salpêtrière, Bâtiment Pharmacie, 47 Boulevard de l'hôpital, Paris, France.
Navarro
Vincent
V
Provenzano
Giovanni
G
Cohen
Ivan
I
Dinocourt
Céline
C
Rivaud-Péchoux
Sophie
S
Fricker
Desdemona
D
Baulac
Michel
M
Miles
Richard
R
Leguern
Eric
E
Baulac
Stéphanie
S
D000367:Age Factors; D000818:Animals; D000831:Animals, Newborn; D001921:Brain / Q000473:pathology / Q000503:physiopathology; D001930:Brain Injuries / Q000209:etiology; D002352:Carrier Proteins / Q000378:metabolism; D027682:Cation Transport Proteins; D004195:Disease Models, Animal; D004569:Electroencephalography / Q000379:methods; D020195:Epilepsy, Reflex / Q000150:complications / Q000209:etiology / Q000235:genetics* / Q000473:pathology; D005786:Gene Expression Regulation / Q000235:genetics; D005904:Glial Fibrillary Acidic Protein / Q000378:metabolism; D047908:Intracellular Signaling Peptides and Proteins; D008565:Membrane Proteins / Q000378:metabolism; D026901:Membrane Transport Proteins; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D011506:Proteins / Q000235:genetics*; D014741:Video Recording / Q000379:methods
D002352:Carrier Proteins; D027682:Cation Transport Proteins; D005904:Glial Fibrillary Acidic Protein; D047908:Intracellular Signaling Peptides and Proteins; C492120:Lgi1 protein, mouse; D008565:Membrane Proteins; D026901:Membrane Transport Proteins; D011506:Proteins; C491177:Slc30a3 protein, mouse