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 regions
2016
50 Hz hippocampal stimulation in refractory epilepsy: Higher level of basal glutamate predicts greater release of glutamate
Cavus I, Widi GA, Duckrow RB, Zaveri H, Kennard JT, Krystal J, Spencer DD. 50 Hz hippocampal stimulation in refractory epilepsy: Higher level of basal glutamate predicts greater release of glutamate. Epilepsia 2016, 57: 288-297. PMID: 26749134, DOI: 10.1111/epi.13269.Peer-Reviewed Original ResearchConceptsBasal glutamate levelsRefractory epilepsyGlutamate effluxBasal glutamateGlutamate levelsElectrical stimulationEpileptic hippocampusGlutamate releaseSeizure groupHz stimulationBrain glutamate releaseHippocampus of patientsStimulation-induced increaseEpilepsy monitoring unitStimulation-induced changesEpileptogenic hippocampusInduced seizuresSeizure inductionSpontaneous seizuresInterictal levelsGlutamate increaseAtrophic hippocampusElectroencephalography evaluationHippocampal stimulationHippocampal electrodes
2012
Evidence for astrocytes as a potential source of the glutamate excess in temporal lobe epilepsy
Perez EL, Lauritzen F, Wang Y, Lee TS, Kang D, Zaveri HP, Chaudhry FA, Ottersen OP, Bergersen LH, Eid T. Evidence for astrocytes as a potential source of the glutamate excess in temporal lobe epilepsy. Neurobiology Of Disease 2012, 47: 331-337. PMID: 22659305, PMCID: PMC3392431, DOI: 10.1016/j.nbd.2012.05.010.Peer-Reviewed Original ResearchConceptsTemporal lobe epilepsyRecurrent seizuresConcentration of glutamateHippocampal formationLobe epilepsyExtracellular glutamateRefractory temporal lobe epilepsyEpileptogenic hippocampal formationExtracellular brain glutamateSubset of patientsSaline-treated ratsStart of infusionRatio of glutamateExcessive glutamateGlutamate excessBrain glutamateExtracellular brainAstrocytesExcessive releaseGS deficiencyRatsSeizuresGlutamateSeparate groupsEpilepsy
2008
Decreased hippocampal volume on MRI is associated with increased extracellular glutamate in epilepsy patients
Cavus I, Pan JW, Hetherington HP, Abi‐Saab W, Zaveri HP, Vives KP, Krystal JH, Spencer SS, Spencer DD. Decreased hippocampal volume on MRI is associated with increased extracellular glutamate in epilepsy patients. Epilepsia 2008, 49: 1358-1366. PMID: 18410365, DOI: 10.1111/j.1528-1167.2008.01603.x.Peer-Reviewed Original ResearchConceptsTemporal lobe epilepsyHippocampal volumeClinical factorsHippocampal atrophyEpileptogenic hippocampusGABA levelsNeurochemical levelsElevated extracellular glutamate levelsContralateral hippocampal volumeIntracranial EEG evaluationMedication-resistant epilepsyRefractory TLE patientsHigh seizure frequencyRelevant clinical factorsSmaller hippocampal volumesExtracellular glutamate levelsFebrile seizure historyTreatment of epilepsySeizure frequencyLobe epilepsySeizure historyTLE patientsAtrophic hippocampusGlutamate levelsExtracellular glutamate