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Kasper J, Caspers S, Lotter LD, Hoffstaedter F, Eickhoff SB, Dukart J. Resting-State Changes in Aging and Parkinson's Disease Are Shaped by Underlying Neurotransmission: A Normative Modeling Study. BIOLOGICAL PSYCHIATRY. COGNITIVE NEUROSCIENCE AND NEUROIMAGING 2024; 9:986-997. [PMID: 38679325 DOI: 10.1016/j.bpsc.2024.04.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2024] [Revised: 03/15/2024] [Accepted: 04/16/2024] [Indexed: 05/01/2024]
Abstract
BACKGROUND Human healthy and pathological aging is linked to a steady decline in brain resting-state activity and connectivity measures. The neurophysiological mechanisms that underlie these changes remain poorly understood. METHODS Making use of recent developments in normative modeling and availability of in vivo maps for various neurochemical systems, we tested in the UK Biobank cohort (n = 25,917) whether and how age- and Parkinson's disease-related resting-state changes in commonly applied local and global activity and connectivity measures colocalize with underlying neurotransmitter systems. RESULTS We found that the distributions of several major neurotransmitter systems including serotonergic, dopaminergic, noradrenergic, and glutamatergic neurotransmission correlated with age-related changes across functional activity and connectivity measures. Colocalization patterns in Parkinson's disease deviated from normative aging trajectories for these, as well as for cholinergic and GABAergic (gamma-aminobutyric acidergic) neurotransmission. The deviation from normal colocalization of brain function and GABAA correlated with disease duration. CONCLUSIONS These findings provide new insights into molecular mechanisms underlying age- and Parkinson's-related brain functional changes by extending the existing evidence elucidating the vulnerability of specific neurochemical attributes to normal aging and Parkinson's disease. The results particularly indicate that alongside dopamine and serotonin, increased vulnerability of glutamatergic, cholinergic, and GABAergic systems may also contribute to Parkinson's disease-related functional alterations. Combining normative modeling and neurotransmitter mapping may aid future research and drug development through deeper understanding of neurophysiological mechanisms that underlie specific clinical conditions.
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Affiliation(s)
- Jan Kasper
- Institute of Systems Neuroscience, Medical Faculty and University Hospital Düsseldorf, Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany; Institute of Neuroscience and Medicine (INM-7), Research Centre Jülich, Jülich, Germany
| | - Svenja Caspers
- Institute for Anatomy I, Medical Faculty and University Hospital Düsseldorf, Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany; Institute of Neuroscience and Medicine (INM-1), Research Centre Jülich, Jülich, Germany
| | - Leon D Lotter
- Institute of Systems Neuroscience, Medical Faculty and University Hospital Düsseldorf, Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany; Institute of Neuroscience and Medicine (INM-7), Research Centre Jülich, Jülich, Germany; Max Planck School of Cognition, Leipzig, Germany
| | - Felix Hoffstaedter
- Institute of Systems Neuroscience, Medical Faculty and University Hospital Düsseldorf, Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany; Institute of Neuroscience and Medicine (INM-7), Research Centre Jülich, Jülich, Germany
| | - Simon B Eickhoff
- Institute of Systems Neuroscience, Medical Faculty and University Hospital Düsseldorf, Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany; Institute of Neuroscience and Medicine (INM-7), Research Centre Jülich, Jülich, Germany
| | - Juergen Dukart
- Institute of Systems Neuroscience, Medical Faculty and University Hospital Düsseldorf, Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany; Institute of Neuroscience and Medicine (INM-7), Research Centre Jülich, Jülich, Germany.
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2
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Toyonaga T, Khattar N, Wu Y, Lu Y, Naganawa M, Gallezot JD, Matuskey D, Mecca AP, Pittman B, Dias M, Nabulsi NB, Finnema SJ, Chen MK, Arnsten A, Radhakrishnan R, Skosnik PD, D'Souza DC, Esterlis I, Huang Y, van Dyck CH, Carson RE. 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. Eur J Nucl Med Mol Imaging 2024; 51:1012-1022. [PMID: 37955791 DOI: 10.1007/s00259-023-06487-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2023] [Accepted: 10/21/2023] [Indexed: 11/14/2023]
Abstract
PURPOSE Aging is a major societal concern due to age-related functional losses. Synapses are crucial components of neural circuits, and synaptic density could be a sensitive biomarker to evaluate brain function. [11C]UCB-J is a positron emission tomography (PET) ligand targeting synaptic vesicle glycoprotein 2A (SV2A), which can be used to evaluate brain synaptic density in vivo. METHODS We evaluated age-related changes in gray matter synaptic density, volume, and blood flow using [11C]UCB-J PET and magnetic resonance imaging (MRI) in a wide age range of 80 cognitive normal subjects (21-83 years old). Partial volume correction was applied to the PET data. RESULTS Significant age-related decreases were found in 13, two, and nine brain regions for volume, synaptic density, and blood flow, respectively. The prefrontal cortex showed the largest volume decline (4.9% reduction per decade: RPD), while the synaptic density loss was largest in the caudate (3.6% RPD) and medial occipital cortex (3.4% RPD). The reductions in caudate are consistent with previous SV2A PET studies and likely reflect that caudate is the site of nerve terminals for multiple major tracts that undergo substantial age-related neurodegeneration. There was a non-significant negative relationship between volume and synaptic density reductions in 16 gray matter regions. CONCLUSION MRI and [11]C-UCB-J PET showed age-related decreases of gray matter volume, synaptic density, and blood flow; however, the regional patterns of the reductions in volume and SV2A binding were different. Those patterns suggest that MR-based measures of GM volume may not be directly representative of synaptic density.
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Affiliation(s)
- Takuya Toyonaga
- PET Center, Department of Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, CT, 06520, USA.
| | - Nikkita Khattar
- PET Center, Department of Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, CT, 06520, USA
| | - Yanjun Wu
- PET Center, Department of Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, CT, 06520, USA
| | - Yihuan Lu
- PET Center, Department of Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, CT, 06520, USA
| | - Mika Naganawa
- PET Center, Department of Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, CT, 06520, USA
| | - Jean-Dominique Gallezot
- PET Center, Department of Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, CT, 06520, USA
| | - David Matuskey
- PET Center, Department of Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, CT, 06520, USA
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA
- Department of Neurology, Yale University School of Medicine, New Haven, CT, USA
| | - Adam P Mecca
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA
- Alzheimer's Disease Research Unit, Yale University School of Medicine, New Haven, CT, USA
| | - Brian Pittman
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA
| | - Mark Dias
- PET Center, Department of Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, CT, 06520, USA
| | - Nabeel B Nabulsi
- PET Center, Department of Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, CT, 06520, USA
| | - Sjoerd J Finnema
- PET Center, Department of Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, CT, 06520, USA
| | - Ming-Kai Chen
- PET Center, Department of Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, CT, 06520, USA
| | - Amy Arnsten
- Department of Neuroscience, Yale University School of Medicine, New Haven, CT, USA
- Department of Psychology, Yale University School of Medicine, New Haven, CT, USA
| | - Rajiv Radhakrishnan
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA
| | - Patrick D Skosnik
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA
- Bouvé College of Health Sciences, Northeastern University Schools of Nursing & Pharmacy/Pharmaceutical Sciences, Boston, MA, USA
| | - Deepak Cyril D'Souza
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA
| | - Irina Esterlis
- PET Center, Department of Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, CT, 06520, USA
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA
| | - Yiyun Huang
- PET Center, Department of Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, CT, 06520, USA
| | - Christopher H van Dyck
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA
- Department of Neurology, Yale University School of Medicine, New Haven, CT, USA
- Alzheimer's Disease Research Unit, Yale University School of Medicine, New Haven, CT, USA
- Department of Neuroscience, Yale University School of Medicine, New Haven, CT, USA
| | - Richard E Carson
- PET Center, Department of Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, CT, 06520, USA
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Lopresti BJ, Royse SK, Mathis CA, Tollefson SA, Narendran R. Beyond monoamines: I. Novel targets and radiotracers for Positron emission tomography imaging in psychiatric disorders. J Neurochem 2023; 164:364-400. [PMID: 35536762 DOI: 10.1111/jnc.15615] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Revised: 04/05/2022] [Accepted: 04/06/2022] [Indexed: 10/18/2022]
Abstract
With the emergence of positron emission tomography (PET) in the late 1970s, psychiatry had access to a tool capable of non-invasive assessment of human brain function. Early applications in psychiatry focused on identifying characteristic brain blood flow and metabolic derangements using radiotracers such as [15 O]H2 O and [18 F]FDG. Despite the success of these techniques, it became apparent that more specific probes were needed to understand the neurochemical bases of psychiatric disorders. The first neurochemical PET imaging probes targeted sites of action of neuroleptic (dopamine D2 receptors) and psychoactive (serotonin receptors) drugs. Based on the centrality of monoamine dysfunction in psychiatric disorders and the measured success of monoamine-enhancing drugs in treating them, the next 30 years witnessed the development of an armamentarium of PET radiopharmaceuticals and imaging methodologies for studying monoamines. Continued development of monoamine-enhancing drugs over this time however was less successful, realizing only modest gains in efficacy and tolerability. As patent protection for many widely prescribed and profitable psychiatric drugs lapsed, drug development pipelines shifted away from monoamines in search of novel targets with the promises of improved efficacy, or abandoned altogether. Over this period, PET radiopharmaceutical development activities closely paralleled drug development priorities resulting in the development of new PET imaging agents for non-monoamine targets. Part one of this review will briefly survey novel PET imaging targets with relevance to the field of psychiatry, which include the metabotropic glutamate receptor type 5 (mGluR5), purinergic P2 X7 receptor, type 1 cannabinoid receptor (CB1 ), phosphodiesterase 10A (PDE10A), and describe radiotracers developed for these and other targets that have matured to human subject investigations. Current limitations of the targets and techniques will also be discussed.
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Affiliation(s)
- Brian J Lopresti
- Departments of Radiology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Sarah K Royse
- Departments of Radiology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Chester A Mathis
- Departments of Radiology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Savannah A Tollefson
- Departments of Radiology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Rajesh Narendran
- Departments of Radiology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA.,Departments of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
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4
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In vivo correlation of serotonin transporter and 1B receptor availability in the human brain: a PET study. Neuropsychopharmacology 2022; 47:1863-1868. [PMID: 35821068 PMCID: PMC9372190 DOI: 10.1038/s41386-022-01369-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 06/13/2022] [Accepted: 06/15/2022] [Indexed: 11/30/2022]
Abstract
Synaptic serotonin levels in the brain are regulated by active transport into the bouton by the serotonin transporter, and by autoreceptors, such as the inhibitory serotonin (5-HT) 1B receptor which, when activated, decreases serotonin release. Animal studies have shown a regulatory link between the two proteins. Evidence of such coupling could translate to an untapped therapeutic potential in augmenting the effect of selective serotonin reuptake inhibitors through pharmacological modulation of 5-HT1B receptors. Here we will for the first time in vivo examine the relationship between 5-HT1B receptors and serotonin transporters in the living human brain. Seventeen healthy individuals were examined with PET twice, using the radioligands [11C]AZ10419369 and [11C]MADAM for quantification of the 5-HT1B receptor and the 5-HT transporter, respectively. The binding potential was calculated for a set of brain regions, and the correlations between the binding estimates of the two radioligands were studied. [11C]AZ10419369 and [11C]MADAM binding was positively correlated in all examined brain regions. In most cortical regions the correlation was strong, e.g., frontal cortex, r(15) = 0.64, p = 0.01 and parietal cortex, r(15) = 0.8, p = 0.0002 while in most subcortical regions, negligible correlations was observed. Though the correlation estimates in cortex should be interpreted with caution due to poor signal to noise ratio of [11C]MADAM binding in these regions, it suggests a link between two key proteins involved in the regulation of synaptic serotonin levels. Our results indicate a need for further studies to address the functional importance of 5-HT1B receptors in treatment with drugs that inhibit serotonin reuptake.
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5
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Jørgensen LM, Henriksen T, Mardosiene S, Keller SH, Stenbæk DS, Hansen HD, Jespersen B, Thomsen C, Weikop P, Svarer C, Knudsen GM. Parkinson patients have a presynaptic serotonergic deficit: A dynamic deep brain stimulation PET study. J Cereb Blood Flow Metab 2021; 41:1954-1963. [PMID: 33461410 PMCID: PMC8327106 DOI: 10.1177/0271678x20982389] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Patients with Parkinson's disease (PD) often suffer from non-motor symptoms, which may be caused by serotonergic dysfunction. Apart from alleviating the motor symptoms, Deep Brain Stimulation (DBS) in the subthalamic nucleus (STN) may also influence non-motor symptoms. The aim of this study is to investigate how turning DBS off affects the serotonergic system. We here exploit a novel functional PET neuroimaging methodology to evaluate the preservation of serotonergic neurons and capacity to release serotonin. We measured cerebral 5-HT1BR binding in 13 DBS-STN treated PD patients, at baseline and after turning DBS off. Ten age-matched volunteers served as controls. Clinical measures of motor symptoms were assessed under the two conditions and correlated to the PET measures of the static and dynamic integrity of the serotonergic system. PD patients exhibited a significant loss of frontal and parietal 5-HT1BR, and the loss was significantly correlated to motor symptom severity. We saw a corresponding release of serotonin, but only in brain regions with preserved 5-HT1BR, suggesting the presence of a presynaptic serotonergic deficit. Our study demonstrates that DBS-STN dynamically regulates the serotonin system in PD, and that preservation of serotonergic functions may be predictive of DBS-STN effects.
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Affiliation(s)
- Louise M Jørgensen
- Neurobiology Research Unit, Department of Neurology, Rigshospitalet, Copenhagen, Denmark.,Institute of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark
| | - Tove Henriksen
- Department of Neurology, Bispebjerg Hospital, Copenhagen, Denmark
| | | | - Sune H Keller
- Department of Clinical Physiology, Nuclear Medicine and PET, Rigshospitalet, Copenhagen, Denmark
| | - Dea S Stenbæk
- Neurobiology Research Unit, Department of Neurology, Rigshospitalet, Copenhagen, Denmark
| | - Hanne D Hansen
- Neurobiology Research Unit, Department of Neurology, Rigshospitalet, Copenhagen, Denmark
| | - Bo Jespersen
- Department of Neurosurgery, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
| | - Carsten Thomsen
- Department of Radiology, Rigshospitalet, University of Copenhagen, Denmark.,Research Center for Advanced Imaging, Zealand University Hospital, Roskilde, Denmark
| | - Pia Weikop
- Center for Basic and Translational Neuroscience, Nedergaard Laboratory, Division of Glial Disease and Therapeutics, University of Copenhagen, Copenhagen, Denmark
| | - Claus Svarer
- Neurobiology Research Unit, Department of Neurology, Rigshospitalet, Copenhagen, Denmark
| | - Gitte M Knudsen
- Neurobiology Research Unit, Department of Neurology, Rigshospitalet, Copenhagen, Denmark.,Institute of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark
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6
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Matheson GJ. We need to talk about reliability: making better use of test-retest studies for study design and interpretation. PeerJ 2019; 7:e6918. [PMID: 31179173 PMCID: PMC6536112 DOI: 10.7717/peerj.6918] [Citation(s) in RCA: 104] [Impact Index Per Article: 20.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2018] [Accepted: 04/07/2019] [Indexed: 12/31/2022] Open
Abstract
Neuroimaging, in addition to many other fields of clinical research, is both time-consuming and expensive, and recruitable patients can be scarce. These constraints limit the possibility of large-sample experimental designs, and often lead to statistically underpowered studies. This problem is exacerbated by the use of outcome measures whose accuracy is sometimes insufficient to answer the scientific questions posed. Reliability is usually assessed in validation studies using healthy participants, however these results are often not easily applicable to clinical studies examining different populations. I present a new method and tools for using summary statistics from previously published test-retest studies to approximate the reliability of outcomes in new samples. In this way, the feasibility of a new study can be assessed during planning stages, and before collecting any new data. An R package called relfeas also accompanies this article for performing these calculations. In summary, these methods and tools will allow researchers to avoid performing costly studies which are, by virtue of their design, unlikely to yield informative conclusions.
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Affiliation(s)
- Granville J. Matheson
- Department of Clinical Neuroscience, Center for Psychiatry Research, Karolinska Institutet and Stockholm County Council, Stockholm, Sweden
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7
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Reduced serotonin receptors and transporters in normal aging adults: a meta-analysis of PET and SPECT imaging studies. Neurobiol Aging 2019; 80:1-10. [PMID: 31055162 DOI: 10.1016/j.neurobiolaging.2019.03.021] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2018] [Revised: 03/18/2019] [Accepted: 03/31/2019] [Indexed: 12/31/2022]
Abstract
Alterations in serotonin (5-HT) function have been hypothesized to underlie a range of physiological, emotional, and cognitive changes in older age. Here, we conducted a quantitative synthesis and comparison of the effects of age on 5-HT receptors and transporters from cross-sectional positron emission tomography and single-photon emission computed tomography imaging studies. Random-effects meta-analyses of 31 studies including 1087 healthy adults yielded large negative effects of age in 5-HT-2A receptors (largest in global cortex), moderate negative effects of age in 5-HT transporters (largest in thalamus), and small negative effects of age in 5-HT-1A receptors (largest in parietal cortex). Presynaptic 5-HT-1A autoreceptors in raphe/midbrain, however, were preserved across adulthood. Adult age differences were significantly larger in 5-HT-2A receptors compared with 5-HT-1A receptors. A meta-regression showed that 5-HT target, radionuclide, and publication year significantly moderated the age effects. The findings overall identify reduced serotonergic signal transmission in healthy aging. The evidence for the relative preservation of 5-HT-1A compared with 5-HT-2A receptors may partially explain psychological age differences, such as why older adults use more emotion-focused rather than problem-focused coping strategies.
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8
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da Cunha-Bang S, Fisher PM, Hjordt LV, Perfalk E, Beliveau V, Holst K, Knudsen GM. Men with high serotonin 1B receptor binding respond to provocations with heightened amygdala reactivity. Neuroimage 2018; 166:79-85. [DOI: 10.1016/j.neuroimage.2017.10.032] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Revised: 10/12/2017] [Accepted: 10/16/2017] [Indexed: 10/18/2022] Open
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9
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Functional Characterization of 5-HT 1B Receptor Drugs in Nonhuman Primates Using Simultaneous PET-MR. J Neurosci 2017; 37:10671-10678. [PMID: 28972127 DOI: 10.1523/jneurosci.1971-17.2017] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2017] [Revised: 08/24/2017] [Accepted: 09/22/2017] [Indexed: 11/21/2022] Open
Abstract
In the present study, we used a simultaneous PET-MR experimental design to investigate the effects of functionally different compounds (agonist, partial agonist, and antagonist) on 5-HT1B receptor (5-HT1BR) occupancy and the associated hemodynamic responses. In anesthetized male nonhuman primates (n = 3), we used positron emission tomography (PET) imaging with the radioligand [11C]AZ10419369 administered as a bolus followed by constant infusion to measure changes in 5-HT1BR occupancy. Simultaneously, we measured changes in cerebral blood volume (CBV) as a proxy of drug effects on neuronal activity. The 5-HT1BR partial agonist AZ10419369 elicited a dose-dependent biphasic hemodynamic response that was related to the 5-HT1BR occupancy. The magnitude of the response was spatially overlapping with high cerebral 5-HT1BR densities. High doses of AZ10419369 exerted an extracranial tissue vasoconstriction that was comparable to the less blood-brain barrier-permeable 5-HT1BR agonist sumatriptan. By contrast, injection of the antagonist GR127935 did not elicit significant hemodynamic responses, even at a 5-HT1BR cerebral occupancy similar to the one obtained with a high dose of AZ10419369. Given the knowledge we have of the 5-HT1BR and its function and distribution in the brain, the hemodynamic response informs us about the functionality of the given drug: changes in CBV are only produced when the receptor is stimulated by the partial agonist AZ10419369 and not by the antagonist GR127935, consistent with low basal occupancy by endogenous serotonin.SIGNIFICANCE STATEMENT We here show that combined simultaneous positron emission tomography and magnetic resonance imaging uniquely enables the assessment of CNS active compounds. We conducted a series of pharmacological interventions to interrogate 5-HT1B receptor binding and function and determined blood-brain barrier passage of drugs and demonstrate target involvement. Importantly, we show how the spatial and temporal effects on brain hemodynamics provide information about pharmacologically driven downstream CNS drug effects; the brain hemodynamic response shows characteristic dose-related effects that differ depending on agonistic or antagonistic drug characteristics and on local 5-HT1B receptor density. The technique lends itself to a comprehensive in vivo investigation and understanding of drugs' effects in the brain.
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10
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da Cunha-Bang S, Hjordt LV, Dam VH, Stenbæk DS, Sestoft D, Knudsen GM. Anterior cingulate serotonin 1B receptor binding is associated with emotional response inhibition. J Psychiatr Res 2017; 92:199-204. [PMID: 28502766 DOI: 10.1016/j.jpsychires.2017.05.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/04/2017] [Revised: 05/02/2017] [Accepted: 05/05/2017] [Indexed: 01/10/2023]
Abstract
Serotonin has a well-established role in emotional processing and is a key neurotransmitter in impulsive aggression, presumably by facilitating response inhibition and regulating subcortical reactivity to aversive stimuli. In this study 44 men, of whom 19 were violent offenders and 25 were non-offender controls, completed an emotional Go/NoGo task requiring inhibition of prepotent motor responses to emotional facial expressions. We also measured cerebral serotonin 1B receptor (5-HT1BR) binding with [11C]AZ10419369 positron emission tomography within regions of the frontal cortex. We hypothesized that 5-HT1BR would be positively associated with false alarms (failures to inhibit nogo responses) in the context of aversive (angry and fearful) facial expressions. Across groups, we found that frontal cortex 5-HT1BR binding was positively correlated with false alarms when angry faces were go stimuli and neutral faces were nogo stimuli (p = 0.05, corrected alpha = 0.0125), but not with false alarms for non-emotional stimuli (failures to inhibit geometric figures). A posthoc analysis revealed the strongest association in anterior cingulate cortex (p = 0.006). In summary, 5-HT1BRs in the anterior cingulate are involved in withholding a prepotent response in the context of angry faces. Our findings suggest that serotonin modulates response inhibition in the context of certain emotional stimuli.
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Affiliation(s)
- Sofi da Cunha-Bang
- Neurobiology Research Unit, Copenhagen University Hospital, Rigshospitalet, Blegdamsvej 9, DK-2100, Denmark
| | - Liv Vadskjær Hjordt
- Neurobiology Research Unit, Copenhagen University Hospital, Rigshospitalet, Blegdamsvej 9, DK-2100, Denmark; Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3, DK-2200 Copenhagen, Denmark
| | - Vibeke Høyrup Dam
- Neurobiology Research Unit, Copenhagen University Hospital, Rigshospitalet, Blegdamsvej 9, DK-2100, Denmark; Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3, DK-2200 Copenhagen, Denmark
| | - Dea Siggaard Stenbæk
- Neurobiology Research Unit, Copenhagen University Hospital, Rigshospitalet, Blegdamsvej 9, DK-2100, Denmark
| | - Dorte Sestoft
- Ministry of Justice, Clinic of Forensic Psychiatry, Blegdamsvej 6B, DK-2200 Copenhagen, Denmark
| | - Gitte M Knudsen
- Neurobiology Research Unit, Copenhagen University Hospital, Rigshospitalet, Blegdamsvej 9, DK-2100, Denmark; Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3, DK-2200 Copenhagen, Denmark.
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11
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Serotonin 1B Receptor Binding Is Associated With Trait Anger and Level of Psychopathy in Violent Offenders. Biol Psychiatry 2017; 82:267-274. [PMID: 27108021 DOI: 10.1016/j.biopsych.2016.02.030] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/05/2016] [Revised: 02/18/2016] [Accepted: 02/26/2016] [Indexed: 12/30/2022]
Abstract
BACKGROUND The involvement of serotonin in aggression has traditionally been attributed to impaired prefrontal serotonergic inhibitory control of emotional reactions to provocations in antisocial individuals. However, it is unclear which specific serotonergic receptors are involved in the effects. A large body of preclinical research supports a specific role of serotonin 1B receptors (5-HT1BRs) in aggression and impulsivity, but this has never been evaluated in humans. METHODS Nineteen incarcerated violent offenders and 24 healthy control nonoffenders were included and examined with positron emission tomography, using the radioligand [11C]AZ10419369 for quantification of cerebral 5-HT1BR binding in three regions of interest: the anterior cingulate cortex, orbitofrontal cortex, and striatum. RESULTS Group status significantly moderated the association between striatal 5-HT1BRs and trait anger (difference in slopes, pcorrected = .04). In the violent offender group, striatal 5-HT1BR binding was positively correlated with self-reported trait anger (p = .0004), trait psychopathy (p = .008), and level of psychopathy according to the Psychopathy Checklist-Revised (p = .02). We found no group differences in 5-HT1BR binding. CONCLUSIONS Our data demonstrate for the first time in humans a specific involvement of 5-HT1BR binding in anger and psychopathy. 5-HT1BRs putatively represent a molecular target for development of pharmacologic antiaggressive treatments.
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12
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A High-Resolution In Vivo Atlas of the Human Brain's Serotonin System. J Neurosci 2017; 37:120-128. [PMID: 28053035 DOI: 10.1523/jneurosci.2830-16.2016] [Citation(s) in RCA: 208] [Impact Index Per Article: 29.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2016] [Revised: 11/08/2016] [Accepted: 11/12/2016] [Indexed: 02/08/2023] Open
Abstract
The serotonin (5-hydroxytryptamine, 5-HT) system modulates many important brain functions and is critically involved in many neuropsychiatric disorders. Here, we present a high-resolution, multidimensional, in vivo atlas of four of the human brain's 5-HT receptors (5-HT1A, 5-HT1B, 5-HT2A, and 5-HT4) and the 5-HT transporter (5-HTT). The atlas is created from molecular and structural high-resolution neuroimaging data consisting of positron emission tomography (PET) and magnetic resonance imaging (MRI) scans acquired in a total of 210 healthy individuals. Comparison of the regional PET binding measures with postmortem human brain autoradiography outcomes showed a high correlation for the five 5-HT targets and this enabled us to transform the atlas to represent protein densities (in picomoles per milliliter). We also assessed the regional association between protein concentration and mRNA expression in the human brain by comparing the 5-HT density across the atlas with data from the Allen Human Brain atlas and identified receptor- and transporter-specific associations that show the regional relation between the two measures. Together, these data provide unparalleled insight into the serotonin system of the human brain. SIGNIFICANCE STATEMENT We present a high-resolution positron emission tomography (PET)- and magnetic resonance imaging-based human brain atlas of important serotonin receptors and the transporter. The regional PET-derived binding measures correlate strongly with the corresponding autoradiography protein levels. The strong correlation enables the transformation of the PET-derived human brain atlas into a protein density map of the serotonin (5-hydroxytryptamine, 5-HT) system. Next, we compared the regional receptor/transporter protein densities with mRNA levels and uncovered unique associations between protein expression and density at high detail. This new in vivo neuroimaging atlas of the 5-HT system not only provides insight in the human brain's regional protein synthesis, transport, and density, but also represents a valuable source of information for the neuroscience community as a comparative instrument to assess brain disorders.
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Veldman ER, Svedberg MM, Svenningsson P, Lundberg J. Distribution and levels of 5-HT 1B receptors in anterior cingulate cortex of patients with bipolar disorder, major depressive disorder and schizophrenia - An autoradiography study. Eur Neuropsychopharmacol 2017; 27:504-514. [PMID: 28318898 DOI: 10.1016/j.euroneuro.2017.02.011] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/26/2016] [Revised: 02/17/2017] [Accepted: 02/21/2017] [Indexed: 12/19/2022]
Abstract
The serotonin 1B receptor has recently received more interest as a possible new target for pharmacological treatment of psychiatric disorders. However, the exact mechanisms of action remain unclear. This study aimed to examine the binding distribution and levels of the serotonin 1B receptor in-depth in the anterior cingulate cortex (ACC) and provide more insight in its functional role in bipolar disorder (BD), major depressive disorder (MDD) and schizophrenia (SZ). Serotonin 1B receptor binding distribution was visualized with high resolution autoradiography (ARG), using the radioligand [3H]AZ10419369, in postmortem ACC tissue from patients diagnosed with BD (n=14), MDD (n=12), SZ (n=13) and healthy subjects (n=13). Moreover, a quantification of receptor binding was made with ARG, in relation to patient group, age and gender. In all subject groups a significantly higher specific binding of serotonin 1B receptor was measured in the outer ACC layers compared to the inner ACC layers. Correlation analysis with ARG binding patterns of several radioligands resulted in a significant correlation with glutamatergic N-methyl-D-aspartate receptor binding in the outer layers. No significant difference was found between subject groups in binding levels and distribution. In female subjects a significantly lower receptor binding was found than in male subjects, which was most profound in patients diagnosed with MDD. The binding distribution of the serotonin 1B receptor found in this study supports a role in glutamate transmission in the ACC and was not shown to be significantly altered in BD, MDD or SZ. A gender difference in serotonin 1B receptor binding was found.
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Affiliation(s)
- Emma R Veldman
- Center for Psychiatry Research, Department of Clinical Neuroscience, Karolinska Institutet & Stockholm Health Care Services, Stockholm County Council, Stockholm, Sweden.
| | - Marie M Svedberg
- Center for Psychiatry Research, Department of Clinical Neuroscience, Karolinska Institutet & Stockholm Health Care Services, Stockholm County Council, Stockholm, Sweden
| | - Per Svenningsson
- Center for Molecular Medicine, Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Johan Lundberg
- Center for Psychiatry Research, Department of Clinical Neuroscience, Karolinska Institutet & Stockholm Health Care Services, Stockholm County Council, Stockholm, Sweden
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Deen M, Hansen HD, Hougaard A, da Cunha-Bang S, Nørgaard M, Svarer C, Keller SH, Thomsen C, Ashina M, Knudsen GM. Low 5-HT 1B receptor binding in the migraine brain: A PET study. Cephalalgia 2017; 38:519-527. [PMID: 28730894 DOI: 10.1177/0333102417698708] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Background The pathophysiology of migraine may involve dysfunction of serotonergic signaling. In particular, the 5-HT1B receptor is considered a key player due to the efficacy of 5-HT1B receptor agonists for treatment of migraine attacks. Aim To examine the cerebral 5-HT1B receptor binding in interictal migraine patients without aura compared to controls. Methods Eighteen migraine patients, who had been migraine free for >48 hours, and 16 controls were scanned after injection of the 5-HT1B receptor specific radioligand [11C]AZ10419369 for quantification of cerebral 5-HT1B receptor binding. Patients who reported migraine <48 hours after the PET examination were excluded from the final analysis. We defined seven brain regions involved in pain modulation as regions of interest and applied a latent variable model (LVM) to assess the group effect on binding across these regions. Results Our data support a model wherein group status predicts the latent variable ( p = 0.038), with migraine patients having lower 5-HT1B receptor binding across regions compared to controls. Further, in a whole-brain voxel-based analysis, time since last migraine attack correlated positively with 5-HT1B receptor binding in the dorsal raphe and in the midbrain. Conclusion We report here for the first time that migraine patients have low 5-HT1B receptor binding in pain modulating regions, reflecting decreased receptor density. This is either a primary constitutive trait of the migraine brain or secondary to repeated exposure to migraine attacks. We also provide indirect support for the dorsal raphe 5-HT1B receptors being temporarily downregulated during the migraine attack, presumably in response to higher cerebral serotonin levels in the ictal phase.
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Affiliation(s)
- Marie Deen
- 1 Danish Headache Center and Department of Neurology, The Neuroscience Centre, Rigshospitalet, Denmark.,2 Neurobiology Research Unit and Center for Experimental Medicine Neuropharmacology, Department of Neurology, The Neuroscience Centre, Rigshospitalet, Denmark.,3 Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Hanne D Hansen
- 2 Neurobiology Research Unit and Center for Experimental Medicine Neuropharmacology, Department of Neurology, The Neuroscience Centre, Rigshospitalet, Denmark
| | - Anders Hougaard
- 1 Danish Headache Center and Department of Neurology, The Neuroscience Centre, Rigshospitalet, Denmark
| | - Sofi da Cunha-Bang
- 2 Neurobiology Research Unit and Center for Experimental Medicine Neuropharmacology, Department of Neurology, The Neuroscience Centre, Rigshospitalet, Denmark.,3 Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Martin Nørgaard
- 2 Neurobiology Research Unit and Center for Experimental Medicine Neuropharmacology, Department of Neurology, The Neuroscience Centre, Rigshospitalet, Denmark
| | - Claus Svarer
- 2 Neurobiology Research Unit and Center for Experimental Medicine Neuropharmacology, Department of Neurology, The Neuroscience Centre, Rigshospitalet, Denmark
| | - Sune H Keller
- 4 Department of Clinical Physiology, Nuclear Medicine and PET, Rigshospitalet, Copenhagen, Denmark
| | - Carsten Thomsen
- 5 Department of Radiology, Rigshospitalet, Copenhagen, Denmark
| | - Messoud Ashina
- 1 Danish Headache Center and Department of Neurology, The Neuroscience Centre, Rigshospitalet, Denmark.,3 Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Gitte M Knudsen
- 2 Neurobiology Research Unit and Center for Experimental Medicine Neuropharmacology, Department of Neurology, The Neuroscience Centre, Rigshospitalet, Denmark.,3 Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
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Passow S, Thurm F, Li SC. Activating Developmental Reserve Capacity Via Cognitive Training or Non-invasive Brain Stimulation: Potentials for Promoting Fronto-Parietal and Hippocampal-Striatal Network Functions in Old Age. Front Aging Neurosci 2017; 9:33. [PMID: 28280465 PMCID: PMC5322263 DOI: 10.3389/fnagi.2017.00033] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2016] [Accepted: 02/08/2017] [Indexed: 01/06/2023] Open
Abstract
Existing neurocomputational and empirical data link deficient neuromodulation of the fronto-parietal and hippocampal-striatal circuitries with aging-related increase in processing noise and declines in various cognitive functions. Specifically, the theory of aging neuronal gain control postulates that aging-related suboptimal neuromodulation may attenuate neuronal gain control, which yields computational consequences on reducing the signal-to-noise-ratio of synaptic signal transmission and hampering information processing within and between cortical networks. Intervention methods such as cognitive training and non-invasive brain stimulation, e.g., transcranial direct current stimulation (tDCS), have been considered as means to buffer cognitive functions or delay cognitive decline in old age. However, to date the reported effect sizes of immediate training gains and maintenance effects of a variety of cognitive trainings are small to moderate at best; moreover, training-related transfer effects to non-trained but closely related (i.e., near-transfer) or other (i.e., far-transfer) cognitive functions are inconsistent or lacking. Similarly, although applying different tDCS protocols to reduce aging-related cognitive impairments by inducing temporary changes in cortical excitability seem somewhat promising, evidence of effects on short- and long-term plasticity is still equivocal. In this article, we will review and critically discuss existing findings of cognitive training- and stimulation-related behavioral and neural plasticity effects in the context of cognitive aging, focusing specifically on working memory and episodic memory functions, which are subserved by the fronto-parietal and hippocampal-striatal networks, respectively. Furthermore, in line with the theory of aging neuronal gain control we will highlight that developing age-specific brain stimulation protocols and the concurrent applications of tDCS during cognitive training may potentially facilitate short- and long-term cognitive and brain plasticity in old age.
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Affiliation(s)
- Susanne Passow
- Chair of Lifespan Developmental Neuroscience, Department of Psychology, TU Dresden Dresden, Germany
| | - Franka Thurm
- Chair of Lifespan Developmental Neuroscience, Department of Psychology, TU Dresden Dresden, Germany
| | - Shu-Chen Li
- Chair of Lifespan Developmental Neuroscience, Department of Psychology, TU Dresden Dresden, Germany
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16
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Deen M, Christensen CE, Hougaard A, Hansen HD, Knudsen GM, Ashina M. Serotonergic mechanisms in the migraine brain - a systematic review. Cephalalgia 2016; 37:251-264. [PMID: 27013238 DOI: 10.1177/0333102416640501] [Citation(s) in RCA: 59] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Background Migraine is one of the most common and disabling of all medical conditions, affecting 16% of the general population, causing huge socioeconomic costs globally. Current available treatment options are inadequate. Serotonin is a key molecule in the neurobiology of migraine, but the exact role of brain serotonergic mechanisms remains a matter of controversy. Methods We systematically searched PubMed for studies investigating the serotonergic system in the migraine brain by either molecular neuroimaging or electrophysiological methods. Results The literature search resulted in 59 papers, of which 13 were eligible for review. The reviewed papers collectively support the notion that migraine patients have alterations in serotonergic neurotransmission. Most likely, migraine patients have a low cerebral serotonin level between attacks, which elevates during a migraine attack. Conclusion This review suggests that novel methods of investigating the serotonergic system in the migraine brain are warranted. Uncovering the serotonergic mechanisms in migraine pathophysiology could prove useful for the development of future migraine drugs.
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Affiliation(s)
- Marie Deen
- 1 Danish Headache Center, Department of Neurology, The Neuroscience Centre, Rigshospitalet, Denmark.,2 Neurobiology Research Unit and Center for Experimental Medicine Neuropharmacology, Department of Neurology, The Neuroscience Centre, Rigshospitalet, Denmark.,3 Faculty of Health and Medical Sciences, University of Copenhagen, Denmark
| | - Casper Emil Christensen
- 1 Danish Headache Center, Department of Neurology, The Neuroscience Centre, Rigshospitalet, Denmark
| | - Anders Hougaard
- 1 Danish Headache Center, Department of Neurology, The Neuroscience Centre, Rigshospitalet, Denmark
| | - Hanne Demant Hansen
- 2 Neurobiology Research Unit and Center for Experimental Medicine Neuropharmacology, Department of Neurology, The Neuroscience Centre, Rigshospitalet, Denmark
| | - Gitte Moos Knudsen
- 2 Neurobiology Research Unit and Center for Experimental Medicine Neuropharmacology, Department of Neurology, The Neuroscience Centre, Rigshospitalet, Denmark.,3 Faculty of Health and Medical Sciences, University of Copenhagen, Denmark
| | - Messoud Ashina
- 1 Danish Headache Center, Department of Neurology, The Neuroscience Centre, Rigshospitalet, Denmark.,3 Faculty of Health and Medical Sciences, University of Copenhagen, Denmark
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Varrone A, Svenningsson P, Marklund P, Fatouros-Bergman H, Forsberg A, Halldin C, Nilsson LG, Farde L. 5-HT1B receptor imaging and cognition: a positron emission tomography study in control subjects and Parkinson's disease patients. Synapse 2015; 69:365-74. [PMID: 25914348 DOI: 10.1002/syn.21823] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2014] [Revised: 04/12/2015] [Accepted: 04/19/2015] [Indexed: 01/26/2023]
Abstract
INTRODUCTION The serotonin 5-HT1B receptor subtype is involved in the modulation of serotonin release and is a target of interest for neuroreceptor imaging. Previous studies have shown that the serotonin system is affected in Parkinson's disease (PD). Cognitive function, frequently impaired in PD, has been linked to the serotonin system. The aim of this study was to examine whether 5-HT1B receptor availability in the brain of healthy subjects and PD patients is associated with measures of cognitive function. METHODS Twelve control subjects and ten PD patients with normal mini-mental state examination scores were included in this study. Cognitive function was evaluated by assessment of semantic, episodic, and working memory, as well as fluency and visual attention. Creative ability, a measure of divergent thinking, was examined with the alternative uses of objects task. PET measurements were performed with the 5-HT1B receptor-radioligand [(11) C]AZ10419369 using the HRRT system. RESULTS PD patients showed statistically significant lower measures of semantic and episodic memory, as well as creative ability, compared with control subjects. Statistically significant positive correlations were found in control subjects between creative ability and average 5-HT1B receptor availability in grey matter, and in PD patients between scores of Beck Depression Inventory-II and creative ability. CONCLUSION Though creativity has been conventionally linked to dopamine function, our findings in control subjects suggest a link between 5-HT1B receptor availability and creative ability. In PD patients, creative ability was significantly associated with depressive symptoms but not with 5-HT1B receptor availability. This finding deserves further investigation in future studies.
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Affiliation(s)
- Andrea Varrone
- Karolinska Institutet, Department of Clinical Neuroscience, Centre for Psychiatry Research, Stockholm, Sweden.,Stockholm Brain Institute, Stockholm, Sweden
| | - Per Svenningsson
- Stockholm Brain Institute, Stockholm, Sweden.,Karolinska Institutet, Department of Clinical Neuroscience, Centre for Molecular Medicine, Stockholm, Sweden
| | - Petter Marklund
- Stockholm Brain Institute, Stockholm, Sweden.,Department of Psychology, Stockholm University, Sweden
| | - Helena Fatouros-Bergman
- Karolinska Institutet, Department of Clinical Neuroscience, Centre for Psychiatry Research, Stockholm, Sweden
| | - Anton Forsberg
- Karolinska Institutet, Department of Clinical Neuroscience, Centre for Psychiatry Research, Stockholm, Sweden
| | - Christer Halldin
- Karolinska Institutet, Department of Clinical Neuroscience, Centre for Psychiatry Research, Stockholm, Sweden.,Stockholm Brain Institute, Stockholm, Sweden
| | - Lars-Göran Nilsson
- Stockholm Brain Institute, Stockholm, Sweden.,Department of Psychology, Stockholm University, Sweden
| | - Lars Farde
- Karolinska Institutet, Department of Clinical Neuroscience, Centre for Psychiatry Research, Stockholm, Sweden.,Stockholm Brain Institute, Stockholm, Sweden.,AstraZeneca Translational Science Center at Karolinska Institutet, Sweden
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