2014
Brain serotonin synthesis in MDMA (ecstasy) polydrug users: an alpha‐[11C]methyl‐l‐tryptophan study
Booij L, Soucy J, Young S, Regoli M, Gravel P, Diksic M, Leyton M, Pihl R, Benkelfat C. Brain serotonin synthesis in MDMA (ecstasy) polydrug users: an alpha‐[11C]methyl‐l‐tryptophan study. Journal Of Neurochemistry 2014, 131: 634-644. PMID: 25041501, DOI: 10.1111/jnc.12826.Peer-Reviewed Original ResearchConceptsMDMA polydrug usersMDMA usePolydrug usersLong-term neurotoxic effectsBrain serotonin synthesisSerotonin synthesis capacityDistal brain regionsNeurotoxicity of MDMAPositron emission tomographySynthesis capacityTracer alphaSerotonin synthesisNeurotoxic effectsPre-frontal regionsTemporal areaBrain regionsEmission tomographyCompensatory mechanismsTryptophan studiesParietal regionsMethylenedioxymethamphetamine (MDMA) useLonger durationBrainstemMDMA users
2012
Perinatal effects on in vivo measures of human brain serotonin synthesis in adulthood: A 27-year longitudinal study
Booij L, Benkelfat C, Leyton M, Vitaro F, Gravel P, Lévesque M, Arseneault L, Diksic M, Tremblay R. Perinatal effects on in vivo measures of human brain serotonin synthesis in adulthood: A 27-year longitudinal study. European Neuropsychopharmacology 2012, 22: 419-423. PMID: 22257439, DOI: 10.1016/j.euroneuro.2011.11.002.Peer-Reviewed Original ResearchConceptsMedial orbitofrontal cortexOrbitofrontal cortexSerotonin neurotransmissionPerinatal adversityPositron emission tomography scanEarly postnatal stressorsLow birth weightEmission tomography scanBrain serotonin neurotransmissionBrain serotonin synthesisSerotonin synthesis capacityStudies reporting associationLongitudinal studyMental health problemsEffects of childhoodLife-long impactTracer alphaMaternal smokingPerinatal effectsBirth complicationsBirth weightRisk factorsTomography scanSerotonin pathwaySerotonin synthesis
2011
Tryptophan hydroxylase2 gene polymorphisms predict brain serotonin synthesis in the orbitofrontal cortex in humans
Booij L, Turecki G, Leyton M, Gravel P, Lopez De Lara C, Diksic M, Benkelfat C. Tryptophan hydroxylase2 gene polymorphisms predict brain serotonin synthesis in the orbitofrontal cortex in humans. Molecular Psychiatry 2011, 17: 809-817. PMID: 21747395, DOI: 10.1038/mp.2011.79.Peer-Reviewed Original ResearchConceptsPositron emission tomographySerotonin synthesisTryptophan hydroxylase 2Orbitofrontal cortexRate-limiting enzymeSingle nucleotide polymorphismsL-tryptophan trappingRegional serotonin synthesisBrain serotonin synthesisTPH2 single nucleotide polymorphismsDose-effect relationshipBrain clearanceHealthy controlsGene polymorphismsAggressive behavioral phenotypeEmission tomographyHydroxylase 2TPH2 geneGenetic factorsCortexBehavioral phenotypesPolymorphismPatientsHumansLarge sampleBrain Regionalα-[11C]Methyl-L-Tryptophan Trapping in Medication-Free Patients With Obsessive-Compulsive Disorder
Berney A, Leyton M, Gravel P, Sibon I, Sookman D, Neto P, Diksic M, Nakai A, Pinard G, Todorov C, Okazawa H, Blier P, Nordahl T, Benkelfat C. Brain Regionalα-[11C]Methyl-L-Tryptophan Trapping in Medication-Free Patients With Obsessive-Compulsive Disorder. JAMA Psychiatry 2011, 68: 732-741. PMID: 21383250, PMCID: PMC3677917, DOI: 10.1001/archgenpsychiatry.2011.16.Peer-Reviewed Original ResearchConceptsL-tryptophan trappingObsessive-compulsive disorderMedication-free patientsHealthy controlsMcGill University Health CentreGlucose metabolic disturbancesAdults meeting criteriaMain outcome measuresUniversity Health CentrePositron emission tomographyDepartment of PsychiatryStatistical parametric mappingTemporal lobe activityMontreal Neurological InstituteSerotonergic componentReuptake inhibitorsSerotonin dysfunctionClinical efficacySerotonergic abnormalitiesMetabolic disturbancesPostsynaptic changesSymptomatic stateSerotonergic systemHealth centersOutcome measures
2010
Brain Serotonin Synthesis in Adult Males Characterized by Physical Aggression during Childhood: A 21-Year Longitudinal Study
Booij L, Tremblay R, Leyton M, Séguin J, Vitaro F, Gravel P, Perreau-Linck E, Lévesque M, Durand F, Diksic M, Turecki G, Benkelfat C. Brain Serotonin Synthesis in Adult Males Characterized by Physical Aggression during Childhood: A 21-Year Longitudinal Study. PLOS ONE 2010, 5: e11255. PMID: 20582306, PMCID: PMC2889822, DOI: 10.1371/journal.pone.0011255.Peer-Reviewed Original ResearchConceptsPhysical aggressionLongitudinal studyHigher physical aggressionLow serotonin neurotransmissionImpulsive aggressive behaviorSubstance abuse disordersEmotional intelligenceComputerized measuresVulnerability traitsVulnerability factorsOrbitofrontal cortexEnvironmental supportGroup differencesAggressionAbuse disordersAggressive behaviorTracer alphaMultiple indicesPlasma tryptophan levelsBrain serotonin synthesisLow trappingPositron emission tomographyCurrent behaviorSerotonin neurotransmissionImpulsivity
2007
In vivo measurements of brain trapping of C-labelled alpha-methyl-L-tryptophan during acute changes in mood states.
Perreau-Linck E, Beauregard M, Gravel P, Paquette V, Soucy J, Diksic M, Benkelfat C. In vivo measurements of brain trapping of C-labelled alpha-methyl-L-tryptophan during acute changes in mood states. Journal Of Psychiatry And Neuroscience 2007, 32: 430-4. PMID: 18043767, PMCID: PMC2077345.Peer-Reviewed Original ResearchConceptsPositron emission tomographyBrain trappingEmotional statesRight anterior cingulate cortexNeutral emotional stateNeurobiology of emotionAnterior cingulate cortexWhole-brain analysisSubjects repeated-measures designState-related changesAcute changesL-tryptophanAutobiographical memoryRepeated-measures designHealthy peopleCingulate cortexBrain Imaging CenterEmission tomographyMood statesMcConnell Brain Imaging CentreBrain analysisNormal moodExperienced levelScan acquisitionSustained changes
2005
α-[11C]Methyl-l-tryptophan trapping in the orbital and ventral medial prefrontal cortex of suicide attempters
Leyton M, Paquette V, Gravel P, Rosa-Neto P, Weston F, Diksic M, Benkelfat C. α-[11C]Methyl-l-tryptophan trapping in the orbital and ventral medial prefrontal cortex of suicide attempters. European Neuropsychopharmacology 2005, 16: 220-223. PMID: 16269239, DOI: 10.1016/j.euroneuro.2005.09.006.Peer-Reviewed Original ResearchConceptsL-tryptophan trappingPrefrontal cortexHealthy controlsSerotonin synthesisSuicidal behaviorSuicide attemptersRegional serotonin synthesisHigh-lethality suicide attemptsVentral medial prefrontal cortexLow serotonin neurotransmissionMedial prefrontal cortexSerotonin neurotransmissionVentromedial prefrontal cortexSuicide attemptsSuicide intentCortexAlphaAttemptersPatientsNeurotransmission