Featured Publications
Imaging synaptic density in the living human brain
Finnema SJ, Nabulsi NB, Eid T, Detyniecki K, Lin SF, Chen MK, Dhaher R, Matuskey D, Baum E, Holden D, Spencer DD, Mercier J, Hannestad J, Huang Y, Carson RE. Imaging synaptic density in the living human brain. Science Translational Medicine 2016, 8: 348ra96. PMID: 27440727, DOI: 10.1126/scitranslmed.aaf6667.Peer-Reviewed Original ResearchConceptsSynaptic densityPositron emission tomographyPET imagingSynaptic vesicle glycoprotein 2ATemporal lobe epilepsyNumerous brain disordersCentral nervous systemNumber of synapsesJ PET imagingHuman brainHuman PET studiesPredominant neuronsSurgical resectionSynaptic lossLobe epilepsyPsychiatric disordersNervous systemBrain disordersPresynaptic boutonsAlzheimer's diseaseBrain tissueEmission tomographyNeuron contactsTherapeutic monitoringPET studiesAssessing 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
2024
Validation of a Simplified Tissue-to-Reference Ratio Measurement Using SUVR to Assess Synaptic Density Alterations in Alzheimer Disease with [11C]UCB-J PET
Young J, O'Dell R, Naganawa M, Toyonaga T, Chen M, Nabulsi N, Huang Y, Cooper E, Miller A, Lam J, Bates K, Ruan A, Nelsen K, Salardini E, Carson R, van Dyck C, Mecca A. Validation of a Simplified Tissue-to-Reference Ratio Measurement Using SUVR to Assess Synaptic Density Alterations in Alzheimer Disease with [11C]UCB-J PET. Journal Of Nuclear Medicine 2024, jnumed.124.267419. PMID: 39299782, DOI: 10.2967/jnumed.124.267419.Peer-Reviewed Original ResearchDistribution volume ratioSUV ratioSynaptic densityEffect sizeAlzheimer's diseaseLongitudinal study of Alzheimer's diseaseMethods:</b> ParticipantsLongitudinal studyMeasure synaptic densityAD participantsStudy of Alzheimer's diseaseNormal cognitionReference regionOlder adultsMulticenterDensity alterationsSynaptic density patterns in early Alzheimer’s disease assessed by independent component analysis
Fang X, Raval N, O’Dell R, Naganawa M, Mecca A, Chen M, van Dyck C, Carson R. Synaptic density patterns in early Alzheimer’s disease assessed by independent component analysis. Brain Communications 2024, 6: fcae107. PMID: 38601916, PMCID: PMC11004947, DOI: 10.1093/braincomms/fcae107.Peer-Reviewed Original ResearchMedial temporal brain regionsAlzheimer's diseaseTemporal brain regionsCognitive deficitsBrain regionsCognitive impairmentPostmortem studiesBinds to SV2ASynaptic densityReduction of synaptic densityIndependent component analysisSynaptic lossAlzheimerDeficitsImpairmentBrainNeocortexComponent analysisPrimary pathologySV2AA pilot study to evaluate the effect of CT1812 treatment on synaptic density and other biomarkers in Alzheimer’s disease
van Dyck C, Mecca A, O’Dell R, Bartlett H, Diepenbrock N, Huang Y, Hamby M, Grundman M, Catalano S, Caggiano A, Carson R. A pilot study to evaluate the effect of CT1812 treatment on synaptic density and other biomarkers in Alzheimer’s disease. Alzheimer's Research & Therapy 2024, 16: 20. PMID: 38273408, PMCID: PMC10809445, DOI: 10.1186/s13195-024-01382-2.Peer-Reviewed Original ResearchConceptsMild to moderate dementiaPositron emission tomographyAlzheimer's diseaseVolumetric MRIModerate dementiaClinical rating scalesSynaptic vesicle glycoprotein 2ACerebrospinal fluidMouse model of ADPharmacodynamic effectsPlacebo-controlled phase 1 clinical trialBiomarkers of AD pathologyClinical trialsCognitive measuresNominally significant differencesPhase 1 clinical trialModel of ADHippocampal cortexPhase 1/2 studyRating ScaleParallel-group trialSynaptic densityTrial registrationThe clinical trialPlacebo-controlledSigma-2 receptor ligands
2023
Evaluation of a First PET Tracer Suitable for Imaging the Sigma‑2 Receptor in the Brain of Nonhuman Primates
Alluri S, Zheng M, Holden D, Zhang Y, Zhang L, Felchner Z, Li S, Ropchan J, Carson R, Jia H, Huang Y. Evaluation of a First PET Tracer Suitable for Imaging the Sigma‑2 Receptor in the Brain of Nonhuman Primates. Molecular Pharmaceutics 2023, 21: 194-200. PMID: 38013422, DOI: 10.1021/acs.molpharmaceut.3c00750.Peer-Reviewed Original ResearchConceptsAlzheimer's diseaseLimited brain uptakeNonhuman primate brainCentral nervous systemPotential therapeutic targetPositron emission tomography (PET) imagingEmission Tomography ImagingTransmembrane protein 97Sigma-2 receptorsFirst PET tracerBrain penetrantBrain uptakeTherapeutic targetNervous systemPrimate brainNeurological disordersPET tracersNonhuman primatesTomography imagingProtein 97CancerDiseaseBrainCell typesReceptorsSynaptic PET Imaging in Neurodegeneration
Chen M, Matuskey D, Finnema S, Carson R. Synaptic PET Imaging in Neurodegeneration. 2023, 157-167. DOI: 10.1007/978-3-031-35098-6_10.ChaptersAlzheimer's diseaseSynaptic densityProgressive supranuclear palsySynaptic vesicle glycoprotein 2ALarge patient cohortPositron emission tomography (PET) biomarkersInitial PET studiesMultiple neurodegenerative diseasesSupranuclear palsyCorticobasal degenerationLewy bodiesPatient cohortSynapse densityTomography biomarkersClinical valueParkinson's diseaseNeurological diseasesBrain regionsFrontotemporal dementiaPET studiesDiseaseNeurodegenerative diseasesHuntington's diseaseMultiple centersSynaptic vesicle membraneAssessment of Gray Matter Microstructure and Synaptic Density in Alzheimer's Disease: A Multimodal Imaging Study With DTI and SV2A PET
Silva-Rudberg J, Salardini E, O'Dell R, Chen M, Ra J, Georgelos J, Morehouse M, Melino K, Varma P, Toyonaga T, Nabulsi N, Huang Y, Carson R, van Dyck C, Mecca A. Assessment of Gray Matter Microstructure and Synaptic Density in Alzheimer's Disease: A Multimodal Imaging Study With DTI and SV2A PET. American Journal Of Geriatric Psychiatry 2023, 32: 17-28. PMID: 37673749, PMCID: PMC10840732, DOI: 10.1016/j.jagp.2023.08.002.Peer-Reviewed Original ResearchSynaptic densityAlzheimer's diseaseMean diffusivitySynaptic lossGray matter microstructureGray matter mean diffusivityDisease pathologyHippocampal synaptic densityMajor pathological correlateSetting of ADAD-related neuropathologySynaptic vesicle glycoprotein 2AHippocampal mean diffusivityAlzheimer's disease pathologyAmyloid-positive participantsMatter mean diffusivityPositron emission tomography (PET) imagingEmission Tomography ImagingGray matter structuresPathological correlatesPositive participantsInverse associationAD groupCognitive impairmentDiseasePrincipal component analysis of synaptic density measured with [11C]UCB-J PET in early Alzheimer’s disease
O'Dell R, Higgins-Chen A, Gupta D, Chen M, Naganawa M, Toyonaga T, Lu Y, Ni G, Chupak A, Zhao W, Salardini E, Nabulsi N, Huang Y, Arnsten A, Carson R, van Dyck C, Mecca A. Principal component analysis of synaptic density measured with [11C]UCB-J PET in early Alzheimer’s disease. NeuroImage Clinical 2023, 39: 103457. PMID: 37422964, PMCID: PMC10338149, DOI: 10.1016/j.nicl.2023.103457.Peer-Reviewed Original ResearchConceptsCognitive domainsCognitive performanceSubjects' scoresCortical regionsNeuropsychological batteryEarly Alzheimer's diseaseAD groupBilateral regionsNormal participantsNegative loadingsCognitive impairmentCN participantsAlzheimer's diseaseParticipantsStructural correlatesStrong contributionParticipant characteristicsScoresPositive loadingsData-driven approachTotal variancePrincipal component analysisSpecific spatial patternsDecreased synaptic vesicle glycoprotein 2A binding in a rodent model of familial Alzheimer's disease detected by [18F]SDM-16
Zheng C, Toyonaga T, Chen B, Nicholson L, Mennie W, Liu M, Spurrier J, Deluca K, Strittmatter S, Carson R, Huang Y, Cai Z. Decreased synaptic vesicle glycoprotein 2A binding in a rodent model of familial Alzheimer's disease detected by [18F]SDM-16. Frontiers In Neurology 2023, 14: 1045644. PMID: 36846134, PMCID: PMC9945093, DOI: 10.3389/fneur.2023.1045644.Peer-Reviewed Original ResearchStandardized uptake value ratioDistribution volume ratioAlzheimer's diseaseSimplified reference tissue modelSynapse lossMouse modelAPP/PS1 miceAge-matched wild-type miceAPPswe/PS1dE9 mouse modelAPP/PS1 AD mouse modelSlow brain kineticsAD mouse modelSynaptic vesicle glycoprotein 2APseudo-reference regionWild-type miceUptake value ratioMonths of ageDifferent brain regionsDifferent imaging windowsFamilial Alzheimer's diseasePET imaging studiesReference tissue modelPS1 miceBrain stemBrain kineticsInvestigating CNS distribution of PF‐05212377, a P‐glycoprotein substrate, by translation of 5‐HT6 receptor occupancy from non‐human primates to humans
Sawant‐Basak A, Chen L, Lockwood P, Boyden T, Doran A, Mancuso J, Zasadny K, McCarthy T, Morris E, Carson R, Esterlis I, Huang Y, Nabulsi N, Planeta B, Fullerton T. Investigating CNS distribution of PF‐05212377, a P‐glycoprotein substrate, by translation of 5‐HT6 receptor occupancy from non‐human primates to humans. Biopharmaceutics & Drug Disposition 2023, 44: 48-59. PMID: 36825693, DOI: 10.1002/bdd.2351.Peer-Reviewed Original ResearchConceptsNon-human primatesBrain penetrationPositron emission tomographyReceptor occupancyUnbound concentrationsPre-clinical evidenceVivo brain penetrationConcentration-dependent increaseP-glycoprotein substratesPlasma ECsP-gpAlzheimer's diseaseEmission tomographyRat BBBTarget engagementCumulative evidenceDependent increaseTransporter substratesCNS distributionBBBRatsDiseasePrimatesSpecies differencesHumans
2022
Reversal of synapse loss in Alzheimer mouse models by targeting mGluR5 to prevent synaptic tagging by C1Q
Spurrier J, Nicholson L, Fang XT, Stoner AJ, Toyonaga T, Holden D, Siegert TR, Laird W, Allnutt MA, Chiasseu M, Brody AH, Takahashi H, Nies SH, Pérez-Cañamás A, Sadasivam P, Lee S, Li S, Zhang L, Huang YH, Carson RE, Cai Z, Strittmatter SM. Reversal of synapse loss in Alzheimer mouse models by targeting mGluR5 to prevent synaptic tagging by C1Q. Science Translational Medicine 2022, 14: eabi8593. PMID: 35648810, PMCID: PMC9554345, DOI: 10.1126/scitranslmed.abi8593.Peer-Reviewed Original ResearchConceptsPositron emission tomographySilent allosteric modulatorsAlzheimer's diseaseMouse modelPhospho-tau accumulationAged mouse modelAlzheimer mouse modelImmune-mediated attackSAM treatmentMicroglial mediatorsSynaptic engulfmentSynaptic lossAD miceComplement component C1qSynapse lossGlutamate responseSynaptic densityDrug washoutSynaptic localizationTherapeutic benefitCognitive impairmentAllosteric modulatorsEmission tomographyNonhuman primatesComponent C1qImaging of Synaptic Density in Neurodegenerative Disorders
Carson RE, Naganawa M, Toyonaga T, Koohsari S, Yang Y, Chen MK, Matuskey D, Finnema SJ. Imaging of Synaptic Density in Neurodegenerative Disorders. Journal Of Nuclear Medicine 2022, 63: 60s-67s. PMID: 35649655, DOI: 10.2967/jnumed.121.263201.Peer-Reviewed Original ResearchConceptsSynaptic densityAlzheimer's diseaseNeurodegenerative disordersNeurodegenerative diseasesSynaptic vesicle protein 2APotential reference regionsSynaptic density lossLewy body dementiaProgressive supranuclear palsyDisease-modifying therapiesSpecific brain proteinsLarge patient cohortAntiepileptic drug levetiracetamPET imaging resultsMultiple neurodegenerative disordersSynaptic lossSupranuclear palsyCorticobasal degenerationNeuropathologic diseasePatient cohortRat modelClinical valueF-FDGParkinson's diseaseEfficacy assessmentSynaptic density and cognitive performance in Alzheimer's disease: A PET imaging study with [11C]UCB‐J
Mecca AP, O'Dell RS, Sharp ES, Banks ER, Bartlett HH, Zhao W, Lipior S, Diepenbrock NG, Chen M, Naganawa M, Toyonaga T, Nabulsi NB, Vander Wyk B, Arnsten AFT, Huang Y, Carson RE, van Dyck C. Synaptic density and cognitive performance in Alzheimer's disease: A PET imaging study with [11C]UCB‐J. Alzheimer's & Dementia 2022, 18: 2527-2536. PMID: 35174954, PMCID: PMC9381645, DOI: 10.1002/alz.12582.Peer-Reviewed Original ResearchConceptsSynaptic densityEarly Alzheimer's diseaseAlzheimer's diseaseCognitive performanceMajor pathological correlateGray matter volumePositron emission tomography (PET) imagingEmission Tomography ImagingPET imaging studiesIndividual cognitive domainsNeuropathologic studiesSignificant positive associationSynapse lossSynaptic alterationsPathological correlatesNeuropsychological test performanceMatter volumeCognitive impairmentSignificant associationImaging studiesDiseaseTomography imagingGlobal cognitionStrongest predictorPositive association
2021
Association of entorhinal cortical tau deposition and hippocampal synaptic density in older individuals with normal cognition and early Alzheimer's disease
Mecca AP, Chen MK, O'Dell RS, Naganawa M, Toyonaga T, Godek TA, Harris JE, Bartlett HH, Zhao W, Banks ER, Ni GS, Rogers K, Gallezot JD, Ropchan J, Emery PR, Nabulsi NB, Vander Wyk BC, Arnsten AFT, Huang Y, Carson RE, van Dyck CH. Association of entorhinal cortical tau deposition and hippocampal synaptic density in older individuals with normal cognition and early Alzheimer's disease. Neurobiology Of Aging 2021, 111: 44-53. PMID: 34963063, PMCID: PMC8761170, DOI: 10.1016/j.neurobiolaging.2021.11.004.Peer-Reviewed Original ResearchConceptsHippocampal synaptic densitySynaptic densityAlzheimer's diseaseCortical tau depositionEarly neuropathologic changesInitial clinical featuresSynaptic vesicle glycoprotein 2AEarly Alzheimer's diseaseOverall sampleEntorhinal cortical cellsClinical featuresNeuropathologic changesTau depositionTau pathologyInverse associationPerforant pathAD groupSynaptic failureNormal cognitionOlder individualsEarly degenerationDiseaseNormal participantsHippocampusTauComparison of [11C]UCB-J and [18F]FDG PET in Alzheimer’s disease: A tracer kinetic modeling study
Chen MK, Mecca AP, Naganawa M, Gallezot JD, Toyonaga T, Mondal J, Finnema SJ, Lin SF, O’Dell R, McDonald JW, Michalak HR, Vander Wyk B, Nabulsi NB, Huang Y, Arnsten AF, van Dyck CH, Carson RE. Comparison of [11C]UCB-J and [18F]FDG PET in Alzheimer’s disease: A tracer kinetic modeling study. Cerebrovascular And Brain Metabolism Reviews 2021, 41: 2395-2409. PMID: 33757318, PMCID: PMC8393289, DOI: 10.1177/0271678x211004312.Peer-Reviewed Original ResearchConceptsSynaptic densityMedial temporal regionsAlzheimer's diseaseNeocortical regionsTemporal regionsRelative outcome measuresMedial temporal lobeVivo PET imagingJ bindingOutcome measuresTemporal lobeMagnitude of reductionCN participantsBrain regionsAD participantsDiseasePET imagingConcordant reductionNormal participantsSynaptic vesiclesPerfusionMetabolismSuitable markerParticipantsSimilar patternAssociation of Aβ deposition and regional synaptic density in early Alzheimer’s disease: a PET imaging study with [11C]UCB-J
O’Dell R, Mecca AP, Chen MK, Naganawa M, Toyonaga T, Lu Y, Godek TA, Harris JE, Bartlett HH, Banks ER, Kominek VL, Zhao W, Nabulsi NB, Ropchan J, Ye Y, Vander Wyk BC, Huang Y, Arnsten AFT, Carson RE, van Dyck CH. Association of Aβ deposition and regional synaptic density in early Alzheimer’s disease: a PET imaging study with [11C]UCB-J. Alzheimer's Research & Therapy 2021, 13: 11. PMID: 33402201, PMCID: PMC7786921, DOI: 10.1186/s13195-020-00742-y.Peer-Reviewed Original ResearchConceptsRegional Aβ depositionAβ depositionEarly Alzheimer's diseaseSynaptic lossSynaptic densityAlzheimer's diseaseDistribution volume ratioPositron emission tomographyHippocampal synaptic densityMild AD dementiaDeposition of AβSignificant inverse associationAmnestic mild cognitive impairmentWhole-brain analysisMild cognitive impairmentCerebellar reference regionPET imaging studiesPlaque burdenAD dementiaInverse associationPostmortem studiesClinical severityNeurodegenerative processesClinical diseaseLarge cohort
2020
Quantification of SV2A Binding in Rodent Brain Using [18F]SynVesT-1 and PET Imaging
Sadasivam P, Fang XT, Toyonaga T, Lee S, Xu Y, Zheng MQ, Spurrier J, Huang Y, Strittmatter SM, Carson RE, Cai Z. Quantification of SV2A Binding in Rodent Brain Using [18F]SynVesT-1 and PET Imaging. Molecular Imaging And Biology 2020, 23: 372-381. PMID: 33258040, PMCID: PMC8105262, DOI: 10.1007/s11307-020-01567-9.Peer-Reviewed Original ResearchConceptsBrain stemAlzheimer's diseaseMin postinjectionAnimal modelsAPP/PS1 miceReference regionStandardized uptake value ratioDynamic PET imaging dataUptake value ratioRodent brain tissueStatic PET scansDifferent imaging windowsPET imaging dataWild-type controlsReference tissue modelPS1 miceAD pathogenesisTherapeutic effectMouse modelRodent modelsLittermate controlsPET scansRodent brainPreclinical imaging studiesTherapeutic drug efficacyIn vivo measurement of widespread synaptic loss in Alzheimer's disease with SV2A PET
Mecca AP, Chen M, O'Dell RS, Naganawa M, Toyonaga T, Godek TA, Harris JE, Bartlett HH, Zhao W, Nabulsi NB, Vander Wyk B, Varma P, Arnsten AFT, Huang Y, Carson RE, van Dyck C. In vivo measurement of widespread synaptic loss in Alzheimer's disease with SV2A PET. Alzheimer's & Dementia 2020, 16: 974-982. PMID: 32400950, PMCID: PMC7383876, DOI: 10.1002/alz.12097.Peer-Reviewed Original ResearchConceptsWidespread synaptic lossEarly Alzheimer's diseaseSynaptic lossAlzheimer's diseaseSynaptic vesicle glycoprotein 2AGray matter volumeMajor structural correlatePositron emission tomography (PET) imagingEmission Tomography ImagingDistribution volume ratioCerebellar reference regionNeocortical brain regionsSynaptic densityAD progressionConsistent pathologyPotential therapyMatter volumePromising biomarkerCognitive impairmentCN participantsBrain regionsDiseaseTomography imagingNormal participantsStructural correlatesSynthesis and Preclinical Evaluation of an 18F‑Labeled Synaptic Vesicle Glycoprotein 2A PET Imaging Probe: [18F]SynVesT‑2
Cai Z, Li S, Zhang W, Pracitto R, Wu X, Baum E, Finnema SJ, Holden D, Toyonaga T, Lin SF, Lindemann M, Shirali A, Labaree DC, Ropchan J, Nabulsi N, Carson RE, Huang Y. Synthesis and Preclinical Evaluation of an 18F‑Labeled Synaptic Vesicle Glycoprotein 2A PET Imaging Probe: [18F]SynVesT‑2. ACS Chemical Neuroscience 2020, 11: 592-603. PMID: 31961649, DOI: 10.1021/acschemneuro.9b00618.Peer-Reviewed Original ResearchConceptsPET imaging probeHigh specific binding signalsNon-human primate brainSynaptic vesicle glycoprotein 2ATraumatic brain injuryPost-traumatic stress disorderMultiple sclerosisBrain injuryParkinson's diseasePreclinical evaluationSpecific binding signalsPrimate brainAlzheimer's diseaseNeuropsychiatric diseasesPresynaptic vesiclesStress disorderDiseaseImaging probeTransmembrane glycoproteinSclerosisPrognosisEpilepsyInjuryStrokeSV2A