2021
Increased branched‐chain amino acids at baseline and hours before a spontaneous seizure in the human epileptic brain
Ong C, Damisah EC, Gruenbaum SE, Dhaher R, Deng Y, Sandhu MRS, Zaveri HP, Spencer DD, Eid T. Increased branched‐chain amino acids at baseline and hours before a spontaneous seizure in the human epileptic brain. Epilepsia 2021, 62: e88-e97. PMID: 33949690, PMCID: PMC11259155, DOI: 10.1111/epi.16920.Peer-Reviewed Original ResearchMeSH KeywordsAdolescentAdultAmino Acids, Branched-ChainBrain ChemistryChildChild, PreschoolChromatography, High Pressure LiquidDrug Resistant EpilepsyElectrocorticographyElectroencephalographyEpilepsies, PartialExtracellular SpaceFemaleGlutamic AcidHumansIsoleucineMaleMicrodialysisMiddle AgedSeizuresTandem Mass SpectrometryYoung AdultConceptsSpontaneous seizuresDrug-resistant focal epilepsyExtracellular brain glutamateHuman epileptic brainBranched-chain amino acidsBranched chain amino acids valineRefractory epilepsyBrain microdialysisGlutamatergic neurotransmissionFocal epilepsySeizure onsetBrain glutamateEpileptic brainHuman patientsSeizuresBrain regionsDialysis samplesMammalian targetEpilepsyLiquid chromatography-tandem mass spectrometryBaselineBCAAIntracranial electroencephalographyChromatography-tandem mass spectrometryPatientsNetwork-Related Changes in Neurotransmitters and Seizure Propagation During Rodent Epileptogenesis
Dhaher R, Gruenbaum SE, Sandhu MRS, Ottestad-Hansen S, Tu N, Wang Y, Lee TW, Deshpande K, Spencer DD, Danbolt NC, Zaveri HP, Eid T. Network-Related Changes in Neurotransmitters and Seizure Propagation During Rodent Epileptogenesis. Neurology 2021, 96: e2261-e2271. PMID: 33722994, PMCID: PMC8166437, DOI: 10.1212/wnl.0000000000011846.Peer-Reviewed Original ResearchConceptsSpontaneous seizuresSeizure propagationSeizure focusMesial temporal lobe epilepsyExtracellular brain levelsTemporal lobe epilepsyExtracellular glutamate levelsRelevant rodent modelsGlutamine synthetase inhibitor methionine sulfoximineTransporter subtype 1Contralateral hippocampusLobe epilepsyBrain levelsBrain microdialysisExtracellular GABANeurotransmitter levelsSeizure initiationGlutamate levelsSeizure onsetEpilepsy networkRodent modelsSubtype 1EpileptogenesisHippocampusBrain regionsAltered 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
2020
Novel aspects of glutamine synthetase in ammonia homeostasis
Zhou Y, Eid T, Hassel B, Danbolt NC. Novel aspects of glutamine synthetase in ammonia homeostasis. Neurochemistry International 2020, 140: 104809. PMID: 32758585, DOI: 10.1016/j.neuint.2020.104809.Peer-Reviewed Original ResearchMeSH KeywordsAmmoniaAnimalsBrainBrain DiseasesGlutamate-Ammonia LigaseGlutamic AcidGlutamineHomeostasisHumansHyperammonemiaLiverConceptsGamma-aminobutyric acidSevere liver diseaseElevated blood ammoniaAmmonia homeostasisInhibitory neurotransmitters glutamateUrea cycleEffects of hyperammonemiaPotassium bufferingNeurological sequelaeBrain edemaLiver diseaseBrain pathophysiologyUrea cycle pathwayBlood ammoniaExtrahepatic tissuesNeurotransmitter glutamateAmmonia clearanceAminobutyric acidComplete urea cycleCycle pathwayTwo-thirdsGlutamine synthetaseRecent studiesHomeostasisBody ammonia
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