Featured Publications
Assessing Synaptic Density in Alzheimer Disease With Synaptic Vesicle Glycoprotein 2A Positron Emission Tomographic Imaging
Chen MK, Mecca AP, Naganawa M, Finnema SJ, Toyonaga T, Lin SF, Najafzadeh S, Ropchan J, Lu Y, McDonald JW, Michalak HR, Nabulsi NB, Arnsten AFT, Huang Y, Carson RE, van Dyck CH. Assessing Synaptic Density in Alzheimer Disease With Synaptic Vesicle Glycoprotein 2A Positron Emission Tomographic Imaging. JAMA Neurology 2018, 75: 1215-1224. PMID: 30014145, PMCID: PMC6233853, DOI: 10.1001/jamaneurol.2018.1836.Peer-Reviewed Original ResearchConceptsPositron emission tomographic imagingSynaptic vesicle glycoprotein 2ASynaptic densityAlzheimer's diseaseEmission tomographic imagingHigh-resolution PET scanningPET scanningCognitive impairmentDisease-modifying therapiesDisease-modifying treatmentsNormal participantsCross-sectional studyPittsburgh compound BMajor structural correlateAmnestic mild cognitive impairmentMagnetic resonance imagingMild cognitive impairmentJ PET imagingRestoration of synapsesSpecific bindingNeurologic evaluationSynaptic lossDisease stagePostmortem studiesOutcome measures
2023
The regional pattern of age-related synaptic loss in the human brain differs from gray matter volume loss: in vivo PET measurement with [11C]UCB-J
Toyonaga T, Khattar N, Wu Y, Lu Y, Naganawa M, Gallezot J, Matuskey D, Mecca A, Pittman B, Dias M, Nabulsi N, Finnema S, Chen M, Arnsten A, Radhakrishnan R, Skosnik P, D’Souza D, Esterlis I, Huang Y, van Dyck C, Carson R. The regional pattern of age-related synaptic loss in the human brain differs from gray matter volume loss: in vivo PET measurement with [11C]UCB-J. European Journal Of Nuclear Medicine And Molecular Imaging 2023, 51: 1012-1022. PMID: 37955791, DOI: 10.1007/s00259-023-06487-8.Peer-Reviewed Original ResearchSynaptic densityAge-related decreaseMagnetic resonance imagingBlood flowAge-related synaptic lossGray matter volume lossSynaptic density lossPositron emission tomography (PET) ligandSynaptic vesicle glycoprotein 2AVivo PET measurementsMedial occipital cortexGray matter volumeAge-related neurodegenerationGray matter regionsCognitive normal subjectsAge-related changesSynaptic lossNerve terminalsWide age rangeOccipital cortexTomography ligandNormal subjectsGM volumeAge-related functional lossesMatter volume
2021
Preliminary In Vivo Evidence of Reduced Synaptic Density in Human Immunodeficiency Virus (HIV) Despite Antiretroviral Therapy
Weiss JJ, Calvi R, Naganawa M, Toyonaga T, Farhadian SF, Chintanaphol M, Chiarella J, Zheng MQ, Ropchan J, Huang Y, Pietrzak RH, Carson RE, Spudich S. Preliminary In Vivo Evidence of Reduced Synaptic Density in Human Immunodeficiency Virus (HIV) Despite Antiretroviral Therapy. Clinical Infectious Diseases 2021, 73: 1404-1411. PMID: 34050746, PMCID: PMC8528400, DOI: 10.1093/cid/ciab484.Peer-Reviewed Original ResearchConceptsHuman immunodeficiency virusAntiretroviral therapySynaptic densityMagnetic resonance imagingMale PLWHImmunodeficiency virusUnderwent magnetic resonance imagingPositron emission tomographicCross-sectional pilotHIV neuropathogenesisViral suppressionCommon complicationSynaptic injuryNeurological impairmentDynamic biomarkersPLWHTherapeutic studiesCortical areasMotor coordinationPathological hallmarkPET scanningPromising biomarkerTherapeutic interventionsResonance imagingPegboard performanceIdentifying brain networks in synaptic density PET (11C-UCB-J) with independent component analysis
Fang XT, Toyonaga T, Hillmer AT, Matuskey D, Holmes SE, Radhakrishnan R, Mecca AP, van Dyck CH, D’Souza D, Esterlis I, Worhunsky PD, Carson RE. Identifying brain networks in synaptic density PET (11C-UCB-J) with independent component analysis. NeuroImage 2021, 237: 118167. PMID: 34000404, PMCID: PMC8452380, DOI: 10.1016/j.neuroimage.2021.118167.Peer-Reviewed Original ResearchConceptsSynaptic densityResting-state functional magnetic resonance imagingSynaptic vesicle protein 2ALevel-dependent signal fluctuationsBrain networksFunctional magnetic resonance imagingMagnetic resonance imagingAge-related changesHealthy controlsResonance imagingRs-fMRIEffects of sexProtein 2AMultiple comparisonsHuman brainAgePotential utilitySexFirst evidenceCovariance patterns
2018
Dose-Related Target Occupancy and Effects on Circuitry, Behavior, and Neuroplasticity of the Glycine Transporter-1 Inhibitor PF-03463275 in Healthy and Schizophrenia Subjects
D’Souza D, Carson RE, Driesen N, Johannesen J, Ranganathan M, Krystal JH, Ahn K, Bielen K, Carbuto M, Deaso E, D’Souza D, Ranganathan M, Naganawa M, Ranganathan M, D’Souza D, Nabulsi N, Zheng M, Lin S, Huang Y, Carson R, Driesen N, Ahn K, Morgan P, Suckow R, He G, McCarthy G, Krystal J, Johannesen J, Kenney J, Gelernter J, Gueorguieva R, Pittman B. Dose-Related Target Occupancy and Effects on Circuitry, Behavior, and Neuroplasticity of the Glycine Transporter-1 Inhibitor PF-03463275 in Healthy and Schizophrenia Subjects. Biological Psychiatry 2018, 84: 413-421. PMID: 29499855, PMCID: PMC6068006, DOI: 10.1016/j.biopsych.2017.12.019.Peer-Reviewed Original ResearchMeSH KeywordsAdultAzabicyclo CompoundsBrainCognitive DysfunctionDose-Response Relationship, DrugDouble-Blind MethodFemaleGlycine Plasma Membrane Transport ProteinsHumansImidazolesKetamineLong-Term PotentiationMagnetic Resonance ImagingMaleMemory, Short-TermMiddle AgedPositron-Emission TomographySchizophreniaYoung AdultConceptsHealthy control subjectsLong-term potentiationSchizophrenia patientsControl subjectsCognitive impairmentClinical trialsGlyT1 occupancyN-methyl-D-aspartate receptor functionGlycine transporter-1 inhibitorKetamine-induced disruptionKetamine-induced effectsFunctional magnetic resonance imagingMagnetic resonance imagingPositron emission tomographyMemory-related activationF-MKSubstudy 1Schizophrenia subjectsResonance imagingReceptor functionCortical regionsEmission tomographyTarget engagementPotentiationSchizophrenia