2020
Circadian-Like Rhythmicity of Extracellular Brain Glutamate in Epilepsy
Sandhu MRS, Dhaher R, Gruenbaum SE, Raaisa R, Spencer DD, Pavlova MK, Zaveri HP, Eid T. Circadian-Like Rhythmicity of Extracellular Brain Glutamate in Epilepsy. Frontiers In Neurology 2020, 11: 398. PMID: 32499751, PMCID: PMC7242976, DOI: 10.3389/fneur.2020.00398.Peer-Reviewed Original ResearchMesial temporal lobe epilepsyExtracellular brain glutamateSeizure onset regionTemporal lobe epilepsyType of epilepsyExcitatory neurotransmitter glutamateSeizure onset areaTranslational rodent modelEpileptogenic hippocampusLobe epilepsyIntracerebral microdialysisExtracellular glutamateBrain glutamateIndividual patientsRodent modelsControl animalsNeurotransmitter glutamateExtracellular levelsEpilepsySeizuresOnset areaCircadian-like rhythmGlutamateEssential modulatorPatients
2017
(Invited) Conjoint Measurement of Brain Electrophysiology and Neurochemistry
Zaveri H, Ganesh N, Goncharova I, Damisah E, Ong C, Perez E, Staib L, Hirsch L, Petroff O, Spencer D, Eid T. (Invited) Conjoint Measurement of Brain Electrophysiology and Neurochemistry. ECS Meeting Abstracts 2017, MA2017-02: 2329-2329. DOI: 10.1149/ma2017-02/55/2329.Peer-Reviewed Original ResearchInterictal EEG spikesBasal glutamateBrain excitabilityIntractable epilepsyEEG spikesBrain electrophysiologySpike rateBasal extracellular glutamate concentrationsIntracranial EEG monitoringExtracellular glutamate concentrationCo-localized measurementsPossible epilepsy surgeryBrain extracellular glutamateInterictal electroencephalographyMicrodialysis catheterEpilepsy surgeryExtracellular glutamateBrain neurochemistryDialysis probeNeurochemical basisEEG monitoringGlutamate concentrationBrain regionsEpilepsyPatients
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
2009
IMAGING | Physiologic Correlates of Metabolic Imaging in Human Epilepsy
Pan J, Williamson A, Cavus I, Zaveri H, Spencer D, Hetherington H. IMAGING | Physiologic Correlates of Metabolic Imaging in Human Epilepsy. 2009, 1568-1573. DOI: 10.1016/b978-012373961-2.00222-8.Peer-Reviewed Original ResearchHuman epilepsyNAA/Cr ratioMetabolic imagingPCr/ATP ratioLocalization/lateralizationMR spectroscopic studiesEpileptic hippocampusMicrodialysis measuresPathophysiologic correlatesSeizure focusNeuropsychologic dataExtracellular glutamateMetabolic dysfunctionMetabolic pathophysiologyVivo MR spectroscopyElectrophysiological functionPhysiologic correlatesEpilepsyMR spectroscopic measurementsMR spectroscopyCr ratioMitochondrial functionMR spectroscopicMemory functionHuman brain
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 glutamateNeurometabolism in human epilepsy
Pan JW, Williamson A, Cavus I, Hetherington HP, Zaveri H, Petroff OA, Spencer DD. Neurometabolism in human epilepsy. Epilepsia 2008, 49: 31-41. PMID: 18304254, PMCID: PMC3657747, DOI: 10.1111/j.1528-1167.2008.01508.x.Peer-Reviewed Original ResearchMeSH KeywordsAnimalsBrain DiseasesBrain MappingCarbon IsotopesDominance, CerebralElectrodes, ImplantedElectroencephalographyEpilepsyGamma-Aminobutyric AcidGlucoseHippocampusHumansLimbic SystemMagnetic Resonance SpectroscopyMetabolic DiseasesMicrodialysisMitochondrial DiseasesNeural PathwaysNeuronsPositron-Emission TomographyRatsSynaptic TransmissionConceptsNeurometabolic dysfunctionMagnetic resonance spectroscopic imagingHuman epilepsyEpileptic brainHippocampal resectionSclerotic hippocampusPathophysiologic aspectsEpileptogenic processMicrodialysis measuresExtracellular glutamateEpileptic dysfunctionEnergetic dysfunctionHuman studiesDysfunctionNeurotransmitter cyclingNoninvasive functional imagingProfound decreaseMitochondrial injuryBrain functionEpilepsyFunctional imagingMetabolic imagingBrainIntracranial EEGNeurometabolismRecurrent seizures and brain pathology after inhibition of glutamine synthetase in the hippocampus in rats
Eid T, Ghosh A, Wang Y, Beckström H, Zaveri HP, Lee TS, Lai JC, Malthankar-Phatak GH, de Lanerolle NC. Recurrent seizures and brain pathology after inhibition of glutamine synthetase in the hippocampus in rats. Brain 2008, 131: 2061-2070. PMID: 18669513, PMCID: PMC2724901, DOI: 10.1093/brain/awn133.Peer-Reviewed Original ResearchConceptsMesial temporal lobe epilepsyMesial temporal sclerosisRecurrent seizuresTemporal sclerosisBrain pathologyIntractable mesial temporal lobe epilepsyTemporal lobe epilepsyGlutamine synthetase deficiencyNovel animal modelContinuous microinfusionHippocampal atrophyLobe epilepsyGlutamate excessNeuropathological featuresExtracellular glutamateHippocampal neuronsAnimal modelsTherapeutic interventionsHippocampusSeizuresSclerosisSynthetase deficiencyMinimal injuryPatientsRats