TY  - JOUR
AU  - Merseburg, Andrea
AU  - Kasemir, Jacquelin
AU  - Buss, Eric W
AU  - Leroy, Felix
AU  - Bock, Tobias
AU  - Porro, Alessandro
AU  - Barnett, Anastasia
AU  - Tröder, Simon E
AU  - Engeland, Birgit
AU  - Stockebrand, Malte
AU  - Moroni, Anna
AU  - Siegelbaum, Steve
AU  - Isbrandt, Dirk
AU  - Santoro, Bina
TI  - Seizures, behavioral deficits and adverse drug responses in two new genetic mouse models of HCN1 epileptic encephalopathy.
JO  - eLife
VL  - 11
SN  - 2050-084X
CY  - Cambridge
PB  - eLife Sciences Publications
M1  - DZNE-2022-01449
SP  - e70826
PY  - 2022
N1  - CC BY: https://creativecommons.org/licenses/by/4.0/
AB  - De novo mutations in voltage- and ligand-gated channels have been associated with an increasing number of cases of developmental and epileptic encephalopathies, which often fail to respond to classic antiseizure medications. Here, we examine two knock-in mouse models replicating de novo sequence variations in the HCN1 voltage-gated channel gene, p.G391D and p.M153I (Hcn1G380D/+ and Hcn1M142I/+ in mouse), associated with severe drug-resistant neonatal- and childhood-onset epilepsy, respectively. Heterozygous mice from both lines displayed spontaneous generalized tonic-clonic seizures. Animals replicating the p.G391D variant had an overall more severe phenotype, with pronounced alterations in the levels and distribution of HCN1 protein, including disrupted targeting to the axon terminals of basket cell interneurons. In line with clinical reports from patients with pathogenic HCN1 sequence variations, administration of the antiepileptic Na+ channel antagonists lamotrigine and phenytoin resulted in the paradoxical induction of seizures in both mouse lines, consistent with an effect to further impair inhibitory neuron function. We also show that these variants can render HCN1 channels unresponsive to classic antagonists, indicating the need to screen mutated channels to identify novel compounds with diverse mechanism of action. Our results underscore the necessity of tailoring effective therapies for specific channel gene variants, and how strongly validated animal models may provide an invaluable tool towards reaching this objective.
KW  - Animals
KW  - Anticonvulsants
KW  - Brain Diseases: genetics
KW  - Child
KW  - Humans
KW  - Hyperpolarization-Activated Cyclic Nucleotide-Gated Channels: genetics
KW  - Lamotrigine
KW  - Ligand-Gated Ion Channels
KW  - Mice
KW  - Phenytoin
KW  - Potassium Channels: genetics
KW  - Seizures: drug therapy
KW  - Seizures: genetics
KW  - mouse (Other)
KW  - neuroscience (Other)
LB  - PUB:(DE-HGF)16
C2  - pmc:PMC9481245
C6  - pmid:35972069
DO  - DOI:10.7554/eLife.70826
UR  - https://pub.dzne.de/record/165144
ER  -