2021
Small loci of astroglial glutamine synthetase deficiency in the postnatal brain cause epileptic seizures and impaired functional connectivity
Farina MG, Sandhu MRS, Parent M, Sanganahalli BG, Derbin M, Dhaher R, Wang H, Zaveri HP, Zhou Y, Danbolt NC, Hyder F, Eid T. Small loci of astroglial glutamine synthetase deficiency in the postnatal brain cause epileptic seizures and impaired functional connectivity. Epilepsia 2021, 62: 2858-2870. PMID: 34536233, PMCID: PMC9006438, DOI: 10.1111/epi.17072.Peer-Reviewed Original ResearchConceptsPostnatal brainFunctional connectivityContinuous video-electroencephalographic recordingSpontaneous recurrent seizuresPathogenesis of epilepsyGlutamine synthetase deficiencyVideo-electroencephalographic recordingsSpecific animal modelsEx vivo studySeizure thresholdAdult patientsRecurrent seizuresFocal epilepsyAdeno-associated virusHippocampal formationAnimal modelsFocal mannerEpileptic seizuresGS deficiencySmall lociSynthetase deficiencyEpilepsyGradual returnVivo studiesBrainAltered hippocampal astroglial metabolism is associated with aging and preserved spatial learning and memory
Ebersole J, Rose G, Eid T, Behar K, Patrylo P. Altered hippocampal astroglial metabolism is associated with aging and preserved spatial learning and memory. Neurobiology Of Aging 2021, 102: 188-199. PMID: 33774381, DOI: 10.1016/j.neurobiolaging.2021.02.015.Peer-Reviewed Original ResearchConceptsArtificial cerebrospinal fluidAstroglial metabolismNeural metabolismHippocampus-dependent cognitive functionGlutamate-glutamine cyclingFischer 344 ratsHippocampus-dependent learningAge-related decreaseAU ratsCognitive functionLiquid chromatography-tandem mass spectroscopyGlutamatergic neurotransmissionCognitive declineHippocampal slicesSpatial learningCognitive statusHippocampal subregionsCerebrospinal fluidImpaired ratsMetabolism correlateYoung adultsCompensatory changesRatsC-glucoseMemory
2018
Astrocytes and Glutamine Synthetase in Epileptogenesis
Eid T, Lee T, Patrylo P, Zaveri HP. Astrocytes and Glutamine Synthetase in Epileptogenesis. Journal Of Neuroscience Research 2018, 97: 1345-1362. PMID: 30022509, PMCID: PMC6338538, DOI: 10.1002/jnr.24267.Peer-Reviewed Original ResearchConceptsMesial temporal lobe epilepsyTemporal lobe epilepsyLobe epilepsyAstrocytic glutamine synthetaseRole of astrocytesPotassium channel Kir4.1Important causative factorExcitatory amino acid transporters EAAT1Antiepileptogenic interventionsEpileptogenic insultAntiepileptogenic therapiesEpilepsy developmentChannel Kir4.1Aquaporin-4EpilepsyCausative factorsTransporters EAAT1New targetsSuch interventionsTransporters MCT1DysfunctionAstrocytesMetabolic mechanismsGlutamine synthetaseDownstream effects
2006
Changes in glial glutamate transporters in human epileptogenic hippocampus: Inadequate explanation for high extracellular glutamate during seizures
Bjørnsen LP, Eid T, Holmseth S, Danbolt NC, Spencer DD, de Lanerolle NC. Changes in glial glutamate transporters in human epileptogenic hippocampus: Inadequate explanation for high extracellular glutamate during seizures. Neurobiology Of Disease 2006, 25: 319-330. PMID: 17112731, DOI: 10.1016/j.nbd.2006.09.014.Peer-Reviewed Original ResearchMeSH KeywordsAdolescentAdultAmino Acid Transport System X-AGAstrocytesChildChild, PreschoolDown-RegulationEpilepsyEpilepsy, Temporal LobeExcitatory Amino Acid Transporter 1Excitatory Amino Acid Transporter 2Extracellular FluidFemaleGlutamic AcidHippocampusHumansImmunohistochemistryMaleMicroscopy, Electron, TransmissionMiddle AgedUp-RegulationConceptsTemporal lobe epilepsySclerotic hippocampusNeuronal lossExtracellular glutamateGlial glutamate transporters GLASTHigh extracellular glutamate levelsGroups of hippocampiHuman epileptogenic hippocampusLess neuronal lossExtracellular glutamate levelsGlutamate transporter GLASTGlial glutamate transportersVivo dialysis studyHigh extracellular glutamateSuch compensatory changesEpileptogenic hippocampusHippocampal sclerosisLobe epilepsySclerotic groupSeizure focusGlutamate levelsWeak immunoreactivityGLT-1Glutamate transportersHippocampus
2004
Loss of glutamine synthetase in the human epileptogenic hippocampus: possible mechanism for raised extracellular glutamate in mesial temporal lobe epilepsy
Eid T, Thomas M, Spencer D, Rundén-Pran E, Lai J, Malthankar G, Kim J, Danbolt N, Ottersen O, de Lanerolle N. Loss of glutamine synthetase in the human epileptogenic hippocampus: possible mechanism for raised extracellular glutamate in mesial temporal lobe epilepsy. The Lancet 2004, 363: 28-37. PMID: 14723991, DOI: 10.1016/s0140-6736(03)15166-5.Peer-Reviewed Original ResearchConceptsMesial temporal lobe epilepsyTemporal lobe epilepsyMTLE hippocampiLobe epilepsyExtracellular glutamateHigh extracellular glutamate concentrationsAnteromedial temporal lobeHuman epileptogenic hippocampusExtracellular glutamate accumulationResolution of seizuresExtracellular glutamate concentrationGlial glutamate transportersMeans of immunohistochemistryEpileptogenic hippocampusSurgical resectionSeizure generationGlutamate homeostasisTemporal lobeAstroglial proliferationEpileptic seizuresGlutamate transportersHippocampusTherapeutic interventionsGlutamate concentrationWestern blot