2024
Advances and Insights in Positron Emission Tomography Tracers for Metabotropic Glutamate Receptor 4 Imaging
Wang J, Li Y, Fakhri G. Advances and Insights in Positron Emission Tomography Tracers for Metabotropic Glutamate Receptor 4 Imaging. Journal Of Medicinal Chemistry 2024, 67: 10517-10529. PMID: 38924702, PMCID: PMC11290609, DOI: 10.1021/acs.jmedchem.3c02431.Peer-Reviewed Original ResearchConceptsPositive allosteric modulatorsPositron emission tomographyPositron emission tomography radioligandsAllosteric modulatorsMGluR4 positive allosteric modulatorsMetabotropic glutamate receptor subtype 4PET ligandNeurological disordersPositron emission tomography tracersEmission tomographySubtype 4Molecular imaging modalitiesEffective treatmentMetabotropicDisordersParent drugImaging modalitiesPET tracersMGluR4Therapeutic targetPositron emitting radioisotopesSelection of lead compoundsLiving subjectsPositronQuantitative accuracyPET imaging of M4 muscarinic acetylcholine receptors in rhesus macaques using [11C]MK-6884: Quantification with kinetic modeling and receptor occupancy by CVL-231 (emraclidine), a novel positive allosteric modulator
Belov V, Guehl N, Duvvuri S, Iredale P, Moon S, Dhaynaut M, Chakilam S, MacDonagh A, Rice P, Yokell D, Renger J, Fakhri G, Normandin M. PET imaging of M4 muscarinic acetylcholine receptors in rhesus macaques using [11C]MK-6884: Quantification with kinetic modeling and receptor occupancy by CVL-231 (emraclidine), a novel positive allosteric modulator. Cerebrovascular And Brain Metabolism Reviews 2024, 44: 1329-1342. PMID: 38477292, PMCID: PMC11342722, DOI: 10.1177/0271678x241238820.Peer-Reviewed Original ResearchConceptsPositive allosteric modulatorsReceptor occupancyNon-human primatesBinding potentialPositron emission tomographyMuscarinic acetylcholine receptorsAllosteric modulatorsNon-human primate brainM4 muscarinic acetylcholine receptorStriatal hyperdopaminergiaAcetylcholine receptorsBrain regionsCaudate nucleusTotal volume of distributionDose-dependent blockReference regionVolume of distributionPositron emission tomography imagingEmission tomographyReceptor levelsFunction of dosePET scansClinical trialsBlood-basedRhesus macaques
2023
Evaluation of trans- and cis-4‑[18F]Fluorogabapentin for Brain PET Imaging
Zhou Y, Normandin M, Belov V, Macdonald-Soccorso M, Moon S, Sun Y, Fakhri G, Guehl N, Brugarolas P. Evaluation of trans- and cis-4‑[18F]Fluorogabapentin for Brain PET Imaging. ACS Chemical Neuroscience 2023, 14: 4208-4215. PMID: 37947793, PMCID: PMC11485007, DOI: 10.1021/acschemneuro.3c00593.Peer-Reviewed Original ResearchConceptsNeuropathic painRodent models of neuropathic painSubunit of voltage-dependent calcium channelsModel of neuropathic painTreatment of neuropathic painMetabolite-corrected arterial input functionVoltage-dependent calcium channelsMultilinear analysis 1Brain uptakePET imagingDose of gabapentinOne-tissue compartment modelRegional time-activity curvesAdult rhesus macaquesPlasma protein bindingTime-activity curvesModerate brain uptakeCalcium channelsInjured nerveArterial input functionGabapentinRodent modelsAnticonvulsant medicationBrain PET imagingRhesus macaquesAssociation of Novelty-Related Locus Coeruleus Function With Entorhinal Tau Deposition and Memory Decline in Preclinical Alzheimer Disease
Prokopiou P, Engels-Domínguez N, Schultz A, Sepulcre J, Koops E, Papp K, Marshall G, Normandin M, El Fakhri G, Rentz D, Sperling R, Johnson K, Jacobs H. Association of Novelty-Related Locus Coeruleus Function With Entorhinal Tau Deposition and Memory Decline in Preclinical Alzheimer Disease. Neurology 2023, 101: e1206-e1217. PMID: 37491329, PMCID: PMC10516269, DOI: 10.1212/wnl.0000000000207646.Peer-Reviewed Original ResearchConceptsLC activityMemory declineLocus coeruleusCognitive declineEC tauHarvard Aging Brain StudyHuman neuroimaging studiesSteeper memory declineNoradrenergic brainstem nucleiLongitudinal cognitive dataFunctional MRI dataTau depositionAging Brain StudyPreclinical Alzheimer's diseaseTau progressionCortical tau depositionElevated beta-amyloidInterventions promoting resilienceMild cognitive impairmentExecutive dysfunctionExecutive functionNeuroimaging studiesTau spreadingTemporal cortexCognitive compositeInjectable ice slurry for reducing pericardial adipose tissue
Shuhaiber J, Tuchayi S, Bijari F, Guehl N, Wang Y, Farinelli W, Arkun K, Fakhri G, Anderson R, Garibyan L. Injectable ice slurry for reducing pericardial adipose tissue. Lasers In Surgery And Medicine 2023, 55: 674-679. PMID: 37464943, DOI: 10.1002/lsm.23709.Peer-Reviewed Original ResearchConceptsPericardial adipose tissuePericardial adipose tissue volumeChest computed tomographyPAT volumeBaseline chest computed tomographyAnimal modelsSubcutaneous adipose tissue volumesCardiovascular diseaseHigh risk of cardiovascular diseaseAdipose tissueLow patient complianceRisk of cardiovascular diseaseWeight lossPreclinical large animal modelAdipose tissue volumeLarge animal modelBariatric surgeryComputed tomographyPatient complianceHigh riskNovel treatmentTreated groupCT imagesTissue volumeCryolipolysisSuper-resolution in brain positron emission tomography using a real-time motion capture system
Chemli Y, Tétrault M, Marin T, Normandin M, Bloch I, El Fakhri G, Ouyang J, Petibon Y. Super-resolution in brain positron emission tomography using a real-time motion capture system. NeuroImage 2023, 272: 120056. PMID: 36977452, PMCID: PMC10122782, DOI: 10.1016/j.neuroimage.2023.120056.Peer-Reviewed Original ResearchConceptsBrain positron emission tomographySuper-resolutionEvent-by-event basisReal-time motion capture systemSR reconstruction methodTracking cameraVisualization of small structuresPET reconstruction algorithmMoving phantomMeasure target motionLine profilesPET/CT scannerMeasured shiftsImprove image resolutionMotion capture systemMotion tracking devicePositron emission tomographyReconstruction algorithmSpatial resolutionMeasured linesPhantomReal-timeEstimation frameworkIncreased spatial resolutionReconstruction method
2022
Radiochemical Synthesis and Evaluation of 3‑[11C]Methyl-4-aminopyridine in Rodents and Nonhuman Primates for Imaging Potassium Channels in the CNS
Sun Y, Guehl N, Zhou Y, Takahashi K, Belov V, Dhaynaut M, Moon S, Fakhri G, Normandin M, Brugarolas P. Radiochemical Synthesis and Evaluation of 3‑[11C]Methyl-4-aminopyridine in Rodents and Nonhuman Primates for Imaging Potassium Channels in the CNS. ACS Chemical Neuroscience 2022, 13: 3342-3351. PMID: 36417797, PMCID: PMC9732819, DOI: 10.1021/acschemneuro.2c00364.Peer-Reviewed Original ResearchConceptsRegional brain time-activity curvesBrain time-activity curvesOne-tissue compartment modelBlood-brain barrierConsistent with <i>inNonhuman primatesTime-activity curvesPositron emission tomographySpinal cord injuryDemyelinated neuronsNeurological symptomsPotassium channelsNeuronal conductionBrain uptakeEmission tomographyStille cross-couplingMultiple sclerosisCord injurySlow kineticsBrain permeabilityTraumatic brainMyelin sheathStronger binding affinityNeuronsBrainHuman biodistribution and radiation dosimetry of the demyelination tracer [18F]3F4AP
Brugarolas P, Wilks M, Noel J, Kaiser J, Vesper D, Ramos-Torres K, Guehl N, Macdonald-Soccorso M, Sun Y, Rice P, Yokell D, Lim R, Normandin M, El Fakhri G. Human biodistribution and radiation dosimetry of the demyelination tracer [18F]3F4AP. European Journal Of Nuclear Medicine And Molecular Imaging 2022, 50: 344-351. PMID: 36197499, PMCID: PMC9816249, DOI: 10.1007/s00259-022-05980-w.Peer-Reviewed Original ResearchConceptsRadiation dosimetryTime-activity curvesAdverse eventsEffective doseMultiple bed positionsComprehensive metabolic panelNonhuman primatesHealthy human volunteersNo adverse eventsDynamic PET scansVoltage-gated potassiumAnimal models of neurological diseasesNonhuman primate studiesModels of neurological diseasesHuman biodistributionAverage effective doseMetabolic panelDosimetryOLINDA softwareHealthy volunteersUrinary bladderPET scansDemyelinating lesionsBed positionAnimal modelsPET imaging studies to investigate functional expression of mGluR2 using [11C]mG2P001
Yuan G, Dhaynaut M, Guehl N, Neelamegam R, Moon S, Qu X, Poutiainen P, Afshar S, Fakhri G, Normandin M, Brownell A. PET imaging studies to investigate functional expression of mGluR2 using [11C]mG2P001. Cerebrovascular And Brain Metabolism Reviews 2022, 43: 296-308. PMID: 36172629, PMCID: PMC9903221, DOI: 10.1177/0271678x221130387.Peer-Reviewed Original ResearchConceptsPositive allosteric modulatorsPositron emission tomographyNon-human primatesMGluR2 positive allosteric modulatorPositron emission tomography imagingPositive allosteric modulator of mGluR2Metabotropic glutamate receptor 2Positron emission tomography imaging studiesExpression of mGluR2Glutamate receptor 2MGluR2 functionPsychiatric disordersMGluR2 expressionTissue glutamate concentrationMGluR2Expressing mGluR2Allosteric modulatorsRat brainTransfected CHO cellsReceptor 2Glutamate concentrationEmission tomographyImaging studiesPharmacological effectsImaging ligandsDesign, Synthesis, and Characterization of [18F]mG2P026 as a High-Contrast PET Imaging Ligand for Metabotropic Glutamate Receptor 2
Yuan G, Dhaynaut M, Guehl N, Afshar S, Huynh D, Moon S, Iyengar S, Jain M, Pickett J, Kang H, Ondrechen M, Fakhri G, Normandin M, Brownell A. Design, Synthesis, and Characterization of [18F]mG2P026 as a High-Contrast PET Imaging Ligand for Metabotropic Glutamate Receptor 2. Journal Of Medicinal Chemistry 2022, 65: 9939-9954. PMID: 35802702, PMCID: PMC9434700, DOI: 10.1021/acs.jmedchem.2c00593.Peer-Reviewed Original ResearchConceptsPositive allosteric modulatorsMetabotropic glutamate receptor 2Glutamate receptor 2Cu-mediated radiofluorinationPET imaging ligandsReceptor 2High molar activityExcellent radiochemical purityGloSensor assayPositron emission tomography radiotracersClasses of positive allosteric modulatorsNon-human primatesJNJ-46356479Radiochemical yieldBrain heterogeneityAllosteric modulatorsBrain uptakeMGluR2Molar activityLigandBrainBrain permeabilityImaging ligandsBinding kineticsMetabotropicPET imaging of mitochondrial function in acute doxorubicin-induced cardiotoxicity: a proof-of-principle study
Detmer F, Alpert N, Moon S, Dhaynaut M, Guerrero J, Guehl N, Xing F, Brugarolas P, Shoup T, Normandin M, Pelletier-Galarneau M, El Fakhri G, Petibon Y. PET imaging of mitochondrial function in acute doxorubicin-induced cardiotoxicity: a proof-of-principle study. Scientific Reports 2022, 12: 6122. PMID: 35414642, PMCID: PMC9005533, DOI: 10.1038/s41598-022-10004-6.Peer-Reviewed Original ResearchConceptsLeft anterior descending coronary arteryDoxorubicin-induced cardiotoxicityCardiac membrane potentialDoxorubicin infusionMembrane potentialAnimal modelsAcute doxorubicin-induced cardiotoxicityLeft anterior descending coronary artery territoryAcute cardiotoxic effectsAnterior descending coronary arteryControl saline infusionDescending coronary arteryDoxorubicin doseSaline infusionTest infusionCardiotoxic effectsMitochondrial membrane potentialInfusion catheterCoronary arteryInfusionMitochondrial functionDoxorubicinMyocardial areaPET imagingIntracoronary catheterOrganomediated cleavage of benzoyl group enables an efficient synthesis of 1-(6-nitropyridin-2-yl)thiourea and its application for developing 18F-labeled PET tracers
Wang J, Takahashi K, Shoup T, Gong L, Li Y, El Fakhri G, Zhang Z, Brownell A. Organomediated cleavage of benzoyl group enables an efficient synthesis of 1-(6-nitropyridin-2-yl)thiourea and its application for developing 18F-labeled PET tracers. Bioorganic Chemistry 2022, 124: 105804. PMID: 35468416, PMCID: PMC9189786, DOI: 10.1016/j.bioorg.2022.105804.Peer-Reviewed Original ResearchLower novelty-related locus coeruleus function is associated with Aβ-related cognitive decline in clinically healthy individuals
Prokopiou P, Engels-Domínguez N, Papp K, Scott M, Schultz A, Schneider C, Farrell M, Buckley R, Quiroz Y, El Fakhri G, Rentz D, Sperling R, Johnson K, Jacobs H. Lower novelty-related locus coeruleus function is associated with Aβ-related cognitive decline in clinically healthy individuals. Nature Communications 2022, 13: 1571. PMID: 35322012, PMCID: PMC8943159, DOI: 10.1038/s41467-022-28986-2.Peer-Reviewed Original ResearchConceptsCognitive declineLC activityLC-FCFunctional connectivityLocus coeruleusAssociated with altered neuronal activityNeuronal activityFace-name paradigmAD-related cognitive declineHuman imaging researchIn vivo neuronal activityLongitudinal cognitive dataAssociated with cognitive declineBeta-amyloid-PETIndividuals at-riskAlzheimer's diseaseCognitively unimpaired older individualsBeta-amyloidSubcortical regionsFunctional MRICognitive dataNeurofibrillary tauImaging researchHippocampusCognitionImpact of 40 Hz Transcranial Alternating Current Stimulation on Cerebral Tau Burden in Patients with Alzheimer’s Disease: A Case Series1
Dhaynaut M, Sprugnoli G, Cappon D, Macone J, Sanchez J, Normandin M, Guehl N, Koch G, Paciorek R, Connor A, Press D, Johnson K, Pascual-Leone A, Fakhri G, Santarnecchi E. Impact of 40 Hz Transcranial Alternating Current Stimulation on Cerebral Tau Burden in Patients with Alzheimer’s Disease: A Case Series1. Journal Of Alzheimer's Disease 2022, 85: 1667-1676. PMID: 34958021, PMCID: PMC9023125, DOI: 10.3233/jad-215072.Peer-Reviewed Original ResearchConceptsMicroglia activationGamma spectral powerDecrease of microglia activationNo adverse eventsTranscranial alternating current stimulationSlow disease progressionPlacebo-controlled conditionsPreclinical dataCase seriesAdverse eventsGamma oscillationsElectrophysiological assessmentP-tauMouse modelDisease progressionMesial regionMild to moderate ADAnimal modelsPatientsPET imagingAlzheimer's diseaseSpectral powerAD mouse modelAD patientsProtein clearanceSynthesis and Characterization of 5‑(2-Fluoro-4‑[11C]methoxyphenyl)-2,2-dimethyl-3,4-dihydro‑2H‑pyrano[2,3‑b]pyridine-7-carboxamide as a PET Imaging Ligand for Metabotropic Glutamate Receptor 2
Yuan G, Dhaynaut M, Lan Y, Guehl N, Huynh D, Iyengar S, Afshar S, Jain M, Pickett J, Kang H, Wang H, Moon S, Ondrechen M, Wang C, Shoup T, Fakhri G, Normandin M, Brownell A. Synthesis and Characterization of 5‑(2-Fluoro-4‑[11C]methoxyphenyl)-2,2-dimethyl-3,4-dihydro‑2H‑pyrano[2,3‑b]pyridine-7-carboxamide as a PET Imaging Ligand for Metabotropic Glutamate Receptor 2. Journal Of Medicinal Chemistry 2022, 65: 2593-2609. PMID: 35089713, PMCID: PMC9434702, DOI: 10.1021/acs.jmedchem.1c02004.Peer-Reviewed Original ResearchConceptsNegative allosteric modulatorsMetabotropic glutamate receptor 2Positron emission tomographyGlutamate receptor 2MGluR2 functionNeuropsychiatric disordersDrug effectsBrain heterogeneityReceptor 2Allosteric modulatorsMGluR2Nonhuman primatesBrain imagingPositron emission tomography imagingPositron emission tomography imaging ligandsHigh molar activityEmission tomographyExcellent radiochemical purityImaging ligandsBlocking agentsPET imagingMolar activityTherapeutic targetMetabotropicDisorders
2021
Near-Infrared Fluorescence Imaging of Carotid Plaques in an Atherosclerotic Murine Model
Wu X, Ulumben A, Long S, Katagiri W, Wilks M, Yuan H, Cortese B, Yang C, Kashiwagi S, Choi H, Normandin M, Fakhri G, Zaman R. Near-Infrared Fluorescence Imaging of Carotid Plaques in an Atherosclerotic Murine Model. Biomolecules 2021, 11: 1753. PMID: 34944397, PMCID: PMC8698491, DOI: 10.3390/biom11121753.Peer-Reviewed Original ResearchNeurovascular imaging with QUTE-CE MRI in APOE4 rats reveals early vascular abnormalities
Leaston J, Ferris C, Kulkarni P, Chandramohan D, van de Ven A, Qiao J, Timms L, Sepulcre J, Fakhri G, Ma C, Normandin M, Gharagouzloo C. Neurovascular imaging with QUTE-CE MRI in APOE4 rats reveals early vascular abnormalities. PLOS ONE 2021, 16: e0256749. PMID: 34449808, PMCID: PMC8396782, DOI: 10.1371/journal.pone.0256749.Peer-Reviewed Original ResearchConceptsVascular abnormalitiesAPOE-e4Contrast-enhanced magnetic resonance imagingBlood-brain-barrier leakageNeurovascular dysfunctionSmall vessel abnormalitiesMagnetic resonance imagingTri-synaptic circuitBlood-brain-barrierCross-sectional studyFemale ratsSignificant signal increaseHyper-vascularizationCerebrovascular abnormalitiesVessel abnormalitiesNeurovascular imagingQUTE-CEBrain volumeAnimal modelsPathological causesAbnormalitiesHistological validationImaging modalitiesResonance imagingQuantification of Myocardial Mitochondrial Membrane Potential Using PET
Pelletier-Galarneau M, Detmer F, Petibon Y, Normandin M, Ma C, Alpert N, El Fakhri G. Quantification of Myocardial Mitochondrial Membrane Potential Using PET. Current Cardiology Reports 2021, 23: 70. PMID: 33970353, PMCID: PMC8443083, DOI: 10.1007/s11886-021-01500-8.Peer-Reviewed Original ResearchEvaluation of Fluorinated Cromolyn Derivatives as Potential Therapeutics for Alzheimer’s Disease
Shoup T, Griciuc A, Normandin M, Quinti L, Walsh L, Dhaynaut M, Moon S, Guehl N, Brugarolas P, Elmaleh D, Fakhri G, Tanzi R. Evaluation of Fluorinated Cromolyn Derivatives as Potential Therapeutics for Alzheimer’s Disease. Journal Of Alzheimer's Disease 2021, 80: 775-786. PMID: 33579853, DOI: 10.3233/jad-201419.Peer-Reviewed Original ResearchConceptsMicroglial cellsCell toxicityPET imagingMultifactorial mechanism of actionBV2 microglial cellsDose-dependent mannerBV2 microglial cell lineMicroglial cell lineMechanism of actionF-18Multifactorial mechanismsPro-inflammatoryHigher perfusionLow perfusionRhesus macaquesCromolynCell linesIncreased uptakeTracer penetrationEnhanced uptakePotential therapeuticsPerfusionToxicityClearance assayClearanceSynthesis and Characterization of [18F]JNJ-46356479 as the First 18F-Labeled PET Imaging Ligand for Metabotropic Glutamate Receptor 2
Yuan G, Guehl N, Zheng B, Qu X, Moon S, Dhaynaut M, Shoup T, Afshar S, Kang H, Zhang Z, El Fakhri G, Normandin M, Brownell A. Synthesis and Characterization of [18F]JNJ-46356479 as the First 18F-Labeled PET Imaging Ligand for Metabotropic Glutamate Receptor 2. Molecular Imaging And Biology 2021, 23: 527-536. PMID: 33559035, PMCID: PMC8277681, DOI: 10.1007/s11307-021-01586-0.Peer-Reviewed Original ResearchConceptsNon-human primatesIn vivo PET imaging studiesNucleus accumbensGlutamate receptor 2PET imaging ligandsImaging ligandsParietal cortexBrain regionsPET imaging studiesPET radioligandIn vivo PET imaging experimentsVolume of distributionMGluR2C57BL/6 J micePET imaging experimentsPET studiesBrainSprague-Dawley ratsAlzheimer's diseaseBrain permeabilityPre-treatment studyImaging studiesDisordersRat studiesReversible kinetics