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Ikezawa J, Yokochi F, Okiyama R, Kumada S, Tojima M, Kamiyama T, Hanakawa T, Matsuda H, Tanaka F, Nakata Y, Isozaki E. Is Generalized and Segmental Dystonia Accompanied by Impairments in the Dopaminergic System? Front Neurol 2021; 12:751434. [PMID: 34867735 PMCID: PMC8638468 DOI: 10.3389/fneur.2021.751434] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2021] [Accepted: 10/12/2021] [Indexed: 12/30/2022] Open
Abstract
Background: The pathogenesis of dystonia is remarkably diverse. Some types of dystonia, such as DYT5 (DYT-GCH1) and tardive dystonia, are related to dysfunction of the dopaminergic system. Furthermore, on pathological examination, cell loss in the substantia nigra (SN) of patients with dystonia has been reported, suggesting that impaired dopamine production may be involved in DYT5 and in other types of dystonia. Objectives: To investigate functional dopaminergic impairments, we compared patients with dystonia and those with Parkinson's disease (PD) with normal controls using neuromelanin-sensitive magnetic resonance imaging (NM-MRI) and dopamine transporter single photon emission computed tomography (DAT SPECT). Methods: A total of 18, 18, and 27 patients with generalized or segmental dystonia, patients with PD, and healthy controls, respectively, were examined using NM-MRI. The mean area corresponding to NM in the SN (NM-SN) was blindly quantified. DAT SPECT was performed on 17 and eight patients with dystonia and PD, respectively. The imaging data of DAT SPECT were harmonized with the Japanese database using striatum phantom calibration. These imaging data were compared between patients with dystonia or PD and controls from the Japanese database in 256 healthy volunteers using the calibrated specific binding ratio (cSBR). The symptoms of dystonia were evaluated using the Fahn–Marsden Dystonia Rating Scale (FMDRS), and the correlation between the results of imaging data and FMDRS was examined. Results: The mean areas corresponding to NM in the SN (NM-SN) were 31 ± 4.2, 28 ± 3.8, and 43 ± 3.8 pixels in patients with dystonia, PD, and in healthy controls, respectively. The mean cSBRs were 5 ± 0.2, 2.8 ± 0.2, 9.2 (predictive) in patients with dystonia, PD, and in healthy controls, respectively. The NM-SN area (r = −0.49, p < 0.05) and the cSBR (r = −0.54, p < 0.05) were inversely correlated with the FMDRS. There was no significant difference between the dystonia and PD groups regarding NM-SN (p = 0.28). In contrast, the cSBR was lower in patients with PD than in those with dystonia (p < 0.5 × 10−6). Conclusions: Impairments of the dopaminergic system may be involved in developing generalized and segmental dystonia. SN abnormalities in patients with dystonia were supposed to be different from degeneration in PD.
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Affiliation(s)
- Jun Ikezawa
- Department of Neurology, Tokyo Metropolitan Neurological Hospital, Tokyo, Japan.,Department of Neurology and Stroke Medicine, Yokohama City University Graduate School of Medicine, Yokohama, Japan
| | - Fusako Yokochi
- Department of Neurology, Tokyo Metropolitan Neurological Hospital, Tokyo, Japan
| | - Ryoichi Okiyama
- Department of Neurology, Tokyo Metropolitan Neurological Hospital, Tokyo, Japan
| | - Satoko Kumada
- Department of Neuropediatrics, Tokyo Metropolitan Neurological Hospital, Tokyo, Japan
| | - Maya Tojima
- Department of Neurology, Tokyo Metropolitan Neurological Hospital, Tokyo, Japan.,Department of Neurology, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Tsutomu Kamiyama
- Department of Neurology, Tokyo Metropolitan Neurological Hospital, Tokyo, Japan
| | - Takashi Hanakawa
- Integrative Brain Imaging Center, National Center of Neurology and Psychiatry, Tokyo, Japan.,Department of Integrated Neuroanatomy and Neuroimaging, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Hiroshi Matsuda
- Integrative Brain Imaging Center, National Center of Neurology and Psychiatry, Tokyo, Japan
| | - Fumiaki Tanaka
- Department of Neurology and Stroke Medicine, Yokohama City University Graduate School of Medicine, Yokohama, Japan
| | - Yasuhiro Nakata
- Department of Neuroradiology, Tokyo Metropolitan Neurological Hospital, Tokyo, Japan
| | - Eiji Isozaki
- Department of Neurology, Tokyo Metropolitan Neurological Hospital, Tokyo, Japan
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2
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VMAT2 availability in Parkinson's disease with probable REM sleep behaviour disorder. Mol Brain 2021; 14:165. [PMID: 34758845 PMCID: PMC8579554 DOI: 10.1186/s13041-021-00875-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Accepted: 10/29/2021] [Indexed: 11/21/2022] Open
Abstract
REM sleep behaviour disorder (RBD) can be an early non-motor symptom of Parkinson’s disease (PD) with pathology involving mainly the pontine nuclei. Beyond the brainstem, it is unclear if RBD patients comorbid with PD have more affected striatal dopamine denervation compared to PD patients unaffected by RBD (PD-RBD−). To elucidate this, we evaluated the availability of vesicular monoamine transporter 2 (VMAT2), an index of nigrostriatal dopamine innervation, in 15 PD patients with probable RBD (PD-RBD+), 15 PD-RBD−, and 15 age-matched healthy controls (HC) using [11C]DTBZ PET imaging. This technique measured VMAT2 availability within striatal regions of interest (ROI). A mixed effect model was used to compare the radioligand binding of VMAT2 between the three groups for each striatal ROI, while co-varying for sex, cognitive function and depression scores. Multiple regressions were also computed to predict clinical measures from group condition and VMAT2 binding within all ROIs explored. We observed a significant main effect of group condition on VMAT2 availability within the caudate, putamen, ventral striatum, globus pallidus, substantia nigra, and subthalamus. Specifically, our results revealed that PD-RBD+ had lower VMAT2 availability compared to HC in all these regions except for the subthalamus and substantia nigra, while PD-RBD− was significantly lower than HC in all these regions. PD-RBD− showed a negative relationship between motor severity and VMAT2 availability within the left caudate. Our findings reflect that both PD patient subgroups had similar denervation within the nigrostriatal pathway. There were no significant interactions detected between radioligand binding and clinical scores in PD-RBD+. Taken together, VMAT2 and striatal dopamine denervation in general may not be a significant contributor to the pathophysiology of RBD in PD patients. Future studies are encouraged to explore other underlying neural chemistry mechanisms contributing to RBD in PD patients.
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3
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Kilbourn MR. 11C- and 18F-Radiotracers for In Vivo Imaging of the Dopamine System: Past, Present and Future. Biomedicines 2021; 9:108. [PMID: 33499179 PMCID: PMC7912183 DOI: 10.3390/biomedicines9020108] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2020] [Revised: 01/17/2021] [Accepted: 01/19/2021] [Indexed: 12/17/2022] Open
Abstract
The applications of positron emission tomography (PET) imaging to study brain biochemistry, and in particular the aspects of dopamine neurotransmission, have grown significantly over the 40 years since the first successful in vivo imaging studies in humans. In vivo PET imaging of dopaminergic functions of the central nervous system (CNS) including dopamine synthesis, vesicular storage, synaptic release and receptor binding, and reuptake processes, are now routinely used for studies in neurology, psychiatry, drug abuse and addiction, and drug development. Underlying these advances in PET imaging has been the development of the unique radiotracers labeled with positron-emitting radionuclides such as carbon-11 and fluorine-18. This review focuses on a selection of the more accepted and utilized PET radiotracers currently available, with a look at their past, present and future.
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Affiliation(s)
- Michael R Kilbourn
- Department of Radiology, University of Michigan Medical School, Ann Arbor, MI 48105, USA
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4
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Smith GS, Mills KA, Pontone GM, Anderson WS, Perepezko KM, Brasic J, Zhou Y, Brandt J, Butson CR, Holt DP, Mathews WB, Dannals RF, Wong DF, Mari Z. Effect of STN DBS on vesicular monoamine transporter 2 and glucose metabolism in Parkinson's disease. Parkinsonism Relat Disord 2019; 64:235-241. [PMID: 31053531 DOI: 10.1016/j.parkreldis.2019.04.006] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/18/2018] [Revised: 04/04/2019] [Accepted: 04/07/2019] [Indexed: 01/21/2023]
Abstract
INTRODUCTION Deep brain stimulation (DBS) is an established treatment for Parkinson's Disease (PD). Despite the improvement of motor symptoms in most patients by sub-thalamic nucleus (STN) DBS and its widespread use, the neurobiological mechanisms are not completely understood. The objective of the present study was to elucidate the effects of subthalamic nucleus (STN) DBS in PD on the dopamine system and neural circuitry, employing high-resolution positron emission tomography (PET) imaging. The hypotheses tested were that STN DBS would decrease the striatal vesicular monoamine transporter (VMAT2), secondary to an increase in dopamine concentrations, and would decrease striatal cerebral metabolism and increase cortical cerebral metabolism. METHODS PET imaging of the vesicular monoamine transporter (VMAT2) and cerebral glucose metabolism was performed prior to DBS surgery and after 4-6 months of STN stimulation in seven PD patients (mean age 67 ± 7). RESULTS The patients demonstrated significant improvement in motor and neuropsychiatric symptoms after STN DBS. Decreased VMAT2 was observed in the caudate, putamen and associative striatum and in extra-striatal, cortical and limbic regions. Cerebral glucose metabolism was decreased in striatal sub-regions and increased in temporal and parietal cortices and the cerebellum. Decreased striatal VMAT2 was correlated with decreased striatal and increased cortical and limbic metabolism. Improvement of depressive symptoms was correlated with decreased VMAT2 in striatal and extra-striatal regions and with striatal decreases and cortical increases in metabolism. CONCLUSIONS The present results support further investigation of the role of VMAT2, and associated changes in neural circuitry in the improvement of motor and non-motor symptoms with STN DBS in PD.
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Affiliation(s)
- Gwenn S Smith
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, MD, USA; Division of Nuclear Medicine and Molecular Imaging, Russell H. Morgan Department of Radiology and Radiological Sciences, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
| | - Kelly A Mills
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Greg M Pontone
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, MD, USA; Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - W Stanley Anderson
- Department of Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, MD, USA; Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Kate M Perepezko
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - James Brasic
- Section of High Resolution Brain PET, Division of Nuclear Medicine, Russell H. Morgan Department of Radiology and Radiological Sciences, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Yun Zhou
- Section of High Resolution Brain PET, Division of Nuclear Medicine, Russell H. Morgan Department of Radiology and Radiological Sciences, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Jason Brandt
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, MD, USA; Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Christopher R Butson
- Scientific Computing & Imaging (SCI) Institute, Departments of Biomedical Engineering, Neurology, Neurosurgery & Psychiatry, University of Utah, USA
| | - Daniel P Holt
- Division of Nuclear Medicine and Molecular Imaging, Russell H. Morgan Department of Radiology and Radiological Sciences, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - William B Mathews
- Division of Nuclear Medicine and Molecular Imaging, Russell H. Morgan Department of Radiology and Radiological Sciences, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Robert F Dannals
- Division of Nuclear Medicine and Molecular Imaging, Russell H. Morgan Department of Radiology and Radiological Sciences, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Dean F Wong
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, MD, USA; Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA; Section of High Resolution Brain PET, Division of Nuclear Medicine, Russell H. Morgan Department of Radiology and Radiological Sciences, Johns Hopkins University School of Medicine, Baltimore, MD, USA; Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Zoltan Mari
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA; Cleveland Clinic Lou Ruvo Center for Brain Health, Las Vegas, NV, USA
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5
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Cho SS, Christopher L, Koshimori Y, Li C, Lang AE, Houle S, Strafella AP. Decreased pallidal vesicular monoamine transporter type 2 availability in Parkinson's disease: The contribution of the nigropallidal pathway. Neurobiol Dis 2019; 124:176-182. [DOI: 10.1016/j.nbd.2018.11.022] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Revised: 11/01/2018] [Accepted: 11/20/2018] [Indexed: 11/16/2022] Open
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6
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Cao L, Xie M, Zhao C, Tang J, Liu C, Xu Y, Li X, Liu Y, Chen Z. Synthesis and preliminary evaluation of 131I-9-iodovinyl-tetrabenazine targeting vesicular monoamine transporter 2. J Radioanal Nucl Chem 2018. [DOI: 10.1007/s10967-018-5900-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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7
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Kaasinen V, Vahlberg T. Striatal dopamine in
P
arkinson disease: A meta‐analysis of imaging studies. Ann Neurol 2017; 82:873-882. [DOI: 10.1002/ana.25103] [Citation(s) in RCA: 79] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2017] [Revised: 11/20/2017] [Accepted: 11/20/2017] [Indexed: 11/09/2022]
Affiliation(s)
- Valtteri Kaasinen
- Division of Clinical NeurosciencesTurku University Hospital
- Department of NeurologyUniversity of Turku
- Turku PET Centre, University of Turku
| | - Tero Vahlberg
- Departments of Clinical Medicine
- BiostatisticsUniversity of TurkuTurku Finland
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8
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Butcher NJ, Marras C, Pondal M, Rusjan P, Boot E, Christopher L, Repetto GM, Fritsch R, Chow EWC, Masellis M, Strafella AP, Lang AE, Bassett AS. Neuroimaging and clinical features in adults with a 22q11.2 deletion at risk of Parkinson's disease. Brain 2017; 140:1371-1383. [PMID: 28369257 DOI: 10.1093/brain/awx053] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2016] [Accepted: 01/23/2017] [Indexed: 11/14/2022] Open
Abstract
The recurrent 22q11.2 deletion is a genetic risk factor for early-onset Parkinson's disease. Adults with the associated 22q11.2 deletion syndrome (22q11.2DS) may exhibit phenotypes that could help identify those at highest risk and reveal disease trajectories. We investigated clinical and neuroimaging features relevant to Parkinson's disease in 26 adults: 13 with 22q11.2DS at genetic risk of Parkinson's disease (mean age = 41.5 years, standard deviation = 9.7), 12 healthy age and sex-matched controls, and a 22q11.2DS patient with l-DOPA-responsive early-onset Parkinson's disease. Neuroimaging included transcranial sonography and positron emission tomography using 11C-dihydrotetrabenazine (11C-DTBZ), a radioligand that binds to the presynaptic vesicular monoamine transporter. The 22q11.2DS group without Parkinson's disease demonstrated significant motor and olfactory deficits relative to controls. Eight (61.5%) were clinically classified with parkinsonism. Transcranial sonography showed a significantly larger mean area of substantia nigra echogenicity in the 22q11.2DS risk group compared with controls (P = 0.03). The 22q11.2DS patient with Parkinson's disease showed the expected pattern of severely reduced striatal 11C-DTBZ binding. The 22q11.2DS group without Parkinson's disease however showed significantly elevated striatal 11C-DTBZ binding relative to controls (∼33%; P < 0.01). Results were similar within the 22q11.2DS group for those with (n = 7) and without (n = 6) psychotic illness. These findings suggest that manifestations of parkinsonism and/or evolution to Parkinson's disease in this genetic at-risk population may include a hyperdopaminergic mechanism. Adequately powered longitudinal studies and animal models are needed to evaluate the relevance of the observed clinical and imaging phenotypes to Parkinson's disease and other disorders that are more prevalent in 22q11.2DS, such as schizophrenia.
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Affiliation(s)
- Nancy J Butcher
- Clinical Genetics Research Program and Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, Ontario, Canada.,Institute of Medical Science, University of Toronto, Ontario, Canada
| | - Connie Marras
- Morton and Gloria Shulman Movement Disorders Centre, Toronto Western Hospital and the Edmond J. Safra Program in Parkinson's Disease Research, University of Toronto, Toronto, Ontario, Canada.,Division of Neurology, Department of Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Margarita Pondal
- Morton and Gloria Shulman Movement Disorders Centre, Toronto Western Hospital and the Edmond J. Safra Program in Parkinson's Disease Research, University of Toronto, Toronto, Ontario, Canada
| | - Pablo Rusjan
- Research Imaging Centre, Centre for Addiction and Mental Health, Toronto, Ontario, Canada.,Department of Psychiatry, University of Toronto, Toronto, Ontario, Canada
| | - Erik Boot
- Department of Psychiatry, University of Toronto, Toronto, Ontario, Canada.,The Dalglish Family 22q Clinic for Adults with 22q11.2 Deletion Syndrome, and Department of Psychiatry, University Health Network, Toronto, Ontario, Canada
| | - Leigh Christopher
- Institute of Medical Science, University of Toronto, Ontario, Canada.,Morton and Gloria Shulman Movement Disorders Centre, Toronto Western Hospital and the Edmond J. Safra Program in Parkinson's Disease Research, University of Toronto, Toronto, Ontario, Canada.,Research Imaging Centre, Centre for Addiction and Mental Health, Toronto, Ontario, Canada.,Division of Brain, Imaging and Behaviour-Systems Neuroscience, Toronto Western Research Institute, University Hospital Network, University of Toronto, Toronto, Ontario, Canada
| | - Gabriela M Repetto
- Centre for Genetics and Genomics, Facultad de Medicina, Clinica Alemana Universidad del Desarrollo, Santiago, Chile
| | - Rosemarie Fritsch
- Departamento de Psiquiatría y Salud Mental, Clínica Psiquiátrica Recoleta, Universidad de Chile, Santiago, Chile
| | - Eva W C Chow
- Clinical Genetics Research Program and Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, Ontario, Canada.,Department of Psychiatry, University of Toronto, Toronto, Ontario, Canada
| | - Mario Masellis
- Sunnybrook Health Sciences Research Centre, Toronto, Ontario, Canada
| | - Antonio P Strafella
- Institute of Medical Science, University of Toronto, Ontario, Canada.,Morton and Gloria Shulman Movement Disorders Centre, Toronto Western Hospital and the Edmond J. Safra Program in Parkinson's Disease Research, University of Toronto, Toronto, Ontario, Canada.,Division of Neurology, Department of Medicine, University of Toronto, Toronto, Ontario, Canada.,Research Imaging Centre, Centre for Addiction and Mental Health, Toronto, Ontario, Canada.,Division of Brain, Imaging and Behaviour-Systems Neuroscience, Toronto Western Research Institute, University Hospital Network, University of Toronto, Toronto, Ontario, Canada.,Toronto Western Hospital Research Institute, University Health Network, Toronto, Ontario, Canada
| | - Anthony E Lang
- Institute of Medical Science, University of Toronto, Ontario, Canada.,Morton and Gloria Shulman Movement Disorders Centre, Toronto Western Hospital and the Edmond J. Safra Program in Parkinson's Disease Research, University of Toronto, Toronto, Ontario, Canada.,Division of Neurology, Department of Medicine, University of Toronto, Toronto, Ontario, Canada.,Toronto Western Hospital Research Institute, University Health Network, Toronto, Ontario, Canada.,Tanz Centre for Research in Neurodegenerative Diseases, Department of Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Anne S Bassett
- Clinical Genetics Research Program and Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, Ontario, Canada.,Institute of Medical Science, University of Toronto, Ontario, Canada.,Department of Psychiatry, University of Toronto, Toronto, Ontario, Canada.,The Dalglish Family 22q Clinic for Adults with 22q11.2 Deletion Syndrome, and Department of Psychiatry, University Health Network, Toronto, Ontario, Canada.,Toronto General Research Institute, University Health Network, Toronto, Ontario, Canada.,Division of Cardiology, Department of Medicine, University Health Network, Toronto, Ontario, Canada
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9
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Strafella AP, Bohnen NI, Perlmutter JS, Eidelberg D, Pavese N, Van Eimeren T, Piccini P, Politis M, Thobois S, Ceravolo R, Higuchi M, Kaasinen V, Masellis M, Peralta MC, Obeso I, Pineda-Pardo JÁ, Cilia R, Ballanger B, Niethammer M, Stoessl JA. Molecular imaging to track Parkinson's disease and atypical parkinsonisms: New imaging frontiers. Mov Disord 2017; 32:181-192. [DOI: 10.1002/mds.26907] [Citation(s) in RCA: 71] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2016] [Revised: 11/21/2016] [Accepted: 11/27/2016] [Indexed: 12/23/2022] Open
Affiliation(s)
- Antonio P. Strafella
- Morton and Gloria Shulman Movement Disorder Unit & E.J. Safra Parkinson Disease Program, Neurology Div/Dept. Medicine, Toronto Western Hospital, UHN; Krembil Research Institute, UHN; Research Imaging Centre, Campbell Family Mental Health Research Institute, CAMH; University of Toronto; Ontario Canada
| | - Nicolaas I. Bohnen
- University of Michigan & Veterans Administration Medical Center; Ann Arbor Michigan USA
| | - Joel S. Perlmutter
- Neurology, Radiology, Neuroscience, Physical Therapy & Occupational Therapy; Washington University in St. Louis; St. Louis Missouri USA
| | - David Eidelberg
- Center for Neurosciences; The Feinstein Institute for Medical Research; Manhasset New York USA
| | - Nicola Pavese
- Newcastle Magnetic Resonance Centre & Positron Emission Tomography Centre; Newcastle University; Campus for Ageing & Vitality Newcastle upon Tyne United Kingdom
| | - Thilo Van Eimeren
- Multimodal Neuroimaging Group-Department of Nuclear Medicine Department of Neurology-University of Cologne; Institute of Neuroscience and Medicine, Jülich Research Center, German Center for Neurodegenerative Diseases (DZNE); Germany
| | - Paola Piccini
- Neurology Imaging Unit, Centre of Neuroinflammation and Neurodegeneration, Division of Brain Sciences, Hammersmith Campus; Imperial College London; United Kingdom
| | - Marios Politis
- Neurodegeneration Imaging Group, Department of Basic and Clinical Neuroscience, Institute of Psychiatry; Psychology and Neuroscience, King's College London; London United Kingdom
| | - Stephane Thobois
- Hospices Civils de Lyon, Hopital Neurologique Pierre Wertheimer; Université Lyon 1; CNRS, Centre de Neurosciences Cognitives; UMR 5229 Lyon France
| | - Roberto Ceravolo
- Department of Clinical and Experimental Medicine, Movement Disorders and Parkinson Center; University of Pisa; Italy
| | - Makoto Higuchi
- National Institute of Radiological Sciences; National Institutes for Quantum and Radiological Science and Technology; Chiba Japan
| | - Valtteri Kaasinen
- Division of Clinical Neurosciences, Turku University Hospital; Department of Neurology; University of Turku; Turku PET Centre, University of Turku; Turku Finland
| | - Mario Masellis
- Cognitive & Movement Disorders Clinic, Sunnybrook Health Sciences Centre; Hurvitz Brain Sciences Research Program, Sunnybrook Research Institute; University of Toronto; Toronto Ontario Canada
| | - M. Cecilia Peralta
- Movement Disorder and Parkinson's Disease Program; CEMIC University Hospital; Buenos Aires Argentina
| | - Ignacio Obeso
- Centro Integral de Neurociencias (CINAC), Hospitales Madrid Puerta del Sur & Centro de Investigación Biomédica en Red; Enfermedades Neurodegenerativas (CIBERNED); Madrid Spain
| | - Jose Ángel Pineda-Pardo
- Centro Integral de Neurociencias (CINAC), Hospitales Madrid Puerta del Sur & Centro de Investigación Biomédica en Red; Enfermedades Neurodegenerativas (CIBERNED); Madrid Spain
| | - Roberto Cilia
- Parkinson Institute; ASST Gaetano Pini-CTO; Milan Italy
| | - Benedicte Ballanger
- INSERM, U1028; CNRS, UMR5292; Lyon Neuroscience Research Center, Neuroplasticity & Neuropathology of Olfactory Perception Team; University Lyon; France
| | - Martin Niethammer
- Center for Neurosciences; The Feinstein Institute for Medical Research; Manhasset New York USA
| | - Jon A. Stoessl
- Pacific Parkinson's Research Centre & National Parkinson Foundation Centre of Excellence; University of British Columbia & Vancouver Coastal Health; Vancouver British Columbia Canada
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10
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Kish SJ, Boileau I, Callaghan RC, Tong J. Brain dopamine neurone 'damage': methamphetamine users vs. Parkinson's disease - a critical assessment of the evidence. Eur J Neurosci 2017; 45:58-66. [PMID: 27519465 PMCID: PMC5209286 DOI: 10.1111/ejn.13363] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2016] [Revised: 07/28/2016] [Accepted: 08/09/2016] [Indexed: 12/31/2022]
Abstract
The objective of this review is to evaluate the evidence that recreational methamphetamine exposure might damage dopamine neurones in human brain, as predicted by experimental animal findings. Brain dopamine marker data in methamphetamine users can now be compared with those in Parkinson's disease, for which the Oleh Hornykiewicz discovery in Vienna of a brain dopamine deficiency is established. Whereas all examined striatal (caudate and putamen) dopamine neuronal markers are decreased in Parkinson's disease, levels of only some (dopamine, dopamine transporter) but not others (dopamine metabolites, synthetic enzymes, vesicular monoamine transporter 2) are below normal in methamphetamine users. This suggests that loss of dopamine neurones might not be characteristic of methamphetamine exposure in at least some human drug users. In methamphetamine users, dopamine loss was more marked in caudate than in putamen, whereas in Parkinson's disease, the putamen is distinctly more affected. Substantia nigra loss of dopamine-containing cell bodies is characteristic of Parkinson's disease, but similar neuropathological studies have yet to be conducted in methamphetamine users. Similarly, it is uncertain whether brain gliosis, a common feature of brain damage, occurs after methamphetamine exposure in humans. Preliminary epidemiological findings suggest that methamphetamine use might increase risk of subsequent development of Parkinson's disease. We conclude that the available literature is insufficient to indicate that recreational methamphetamine exposure likely causes loss of dopamine neurones in humans but does suggest presence of a striatal dopamine deficiency that, in principle, could be corrected by dopamine substitution medication if safety and subject selection considerations can be resolved.
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Affiliation(s)
- Stephen J. Kish
- Human Brain Laboratory, Research Imaging Centre, Centre for Addiction and Mental Health, Toronto, Ontario, Canada
| | - Isabelle Boileau
- Addiction Imaging Research Group, Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, Ontario, Canada
| | - Russell C. Callaghan
- Northern Medical Program, University of Northern British Columbia (UNBC), Prince George, British Columbia, Canada
| | - Junchao Tong
- Human Brain Laboratory, Research Imaging Centre, Centre for Addiction and Mental Health, Toronto, Ontario, Canada
- Addiction Imaging Research Group, Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, Ontario, Canada
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11
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Jon Stoessl A. Raul de la Fuente‐Fernandez, February 22, 1959–May 11, 2016. Mov Disord 2016; 31:1144-5. [DOI: 10.1002/mds.26700] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2016] [Accepted: 05/20/2016] [Indexed: 11/07/2022] Open
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12
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Rapid Recovery of Vesicular Dopamine Levels in Methamphetamine Users in Early Abstinence. Neuropsychopharmacology 2016; 41:1179-87. [PMID: 26321315 PMCID: PMC4748442 DOI: 10.1038/npp.2015.267] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/08/2015] [Revised: 07/30/2015] [Accepted: 08/21/2015] [Indexed: 11/08/2022]
Abstract
We previously reported very low levels of dopamine in post-mortem striatum of chronic methamphetamine users, raising the possibility that restoration of normal dopamine levels could help in this addiction and perhaps prevent early relapse. To establish relevance of this finding to the living brain, we tested whether striatal [(11)C]-(+)-dihydrotetrabenazine binding, a vesicular monoamine transporter probe sensitive to changes in (stored) vesicular dopamine, is elevated in methamphetamine users. Chronic methamphetamine users underwent [(11)C]-(+)-dihydrotetrabenazine positron emission tomography scans during early (mean 2.6 days) and later (~10 days) abstinence. Striatal [(11)C]-(+)-dihydrotetrabenazine binding was elevated (suggesting low stored dopamine) in methamphetamine users (n=28; 2.6 days after last use) relative to controls (n=22) (+28%, p<0.0001) and correlated with severity and recency of drug use and with cognitive impairment and withdrawal symptoms. Mean [(11)C]-(+)-dihydrotetrabenazine binding levels in the subgroup of methamphetamine users who could remain abstinent ~10 days following last use (n=17) were normal at the follow-up scan. Our imaging data support post-mortem findings and suggest that chronic methamphetamine users have low brain levels of stored dopamine during very early abstinence from MA, which could contribute to behavioral and cognitive deficits. Findings also suggest a rapid recovery of stored dopamine in some methamphetamine users who become abstinent and who therefore might not benefit from dopamine replacement medication (eg, levodopa). Further study is necessary to establish whether those users who could not maintain abstinence for the second scan might have a more severe and persistent dopamine deficiency and who could benefit from this medication.
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Algarni MA, Stoessl AJ. The role of biomarkers and imaging in Parkinson’s disease. Expert Rev Neurother 2016; 16:187-203. [DOI: 10.1586/14737175.2016.1135056] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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Abstract
Movement disorders can be hypokinetic (e.g., parkinsonism), hyperkinetic, or dystonic in nature and commonly arise from altered function in nuclei of the basal ganglia or their connections. As obvious structural changes are often limited, standard imaging plays less of a role than in other neurologic disorders. However, structural imaging is indicated where clinical presentation is atypical, particularly if the disorder is abrupt in onset or remains strictly unilateral. More recent advances in magnetic resonance imaging (MRI) may allow for differentiation between Parkinson's disease and atypical forms of parkinsonism. Functional imaging can assess regional cerebral blood flow (functional MRI (fMRI), positron emission tomography (PET), or single-photon emission computed tomography (SPECT)), cerebral glucose metabolism (PET), neurochemical and neuroreceptor status (PET and SPECT), and pathologic processes such as inflammation or abnormal protein deposition (PET) (Table 49.1). Cerebral blood flow can be assessed at rest, during the performance of motor or cognitive tasks, or in response to a variety of stimuli. In appropriate situations, the correct imaging modality and/or combination of modalities can be used to detect early disease or even preclinical disease, and to monitor disease progression and the effects of disease-modifying interventions. Various approaches are reviewed here.
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Affiliation(s)
- A Jon Stoessl
- Pacific Parkinson's Research Centre and Division of Neurology, Djavad Mowafaghian Centre for Brain Health, University of British Columbia and Vancouver Coastal Health, Vancouver, BC, Canada.
| | - Martin J Mckeown
- Pacific Parkinson's Research Centre and Division of Neurology, Djavad Mowafaghian Centre for Brain Health, University of British Columbia and Vancouver Coastal Health, Vancouver, BC, Canada
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Zlatopolskiy BD, Zischler J, Urusova EA, Endepols H, Kordys E, Frauendorf H, Mottaghy FM, Neumaier B. A Practical One-Pot Synthesis of Positron Emission Tomography (PET) Tracers via Nickel-Mediated Radiofluorination. ChemistryOpen 2015; 4:457-62. [PMID: 26478840 PMCID: PMC4603406 DOI: 10.1002/open.201500056] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2015] [Indexed: 12/28/2022] Open
Abstract
Recently a novel method for the preparation of (18)F-labeled arenes via oxidative [(18)F]fluorination of easily accessible and sufficiently stable nickel complexes with [(18)F]fluoride under exceptionally mild reaction conditions was published. The suitability of this procedure for the routine preparation of clinically relevant positron emission tomography (PET) tracers, 6-[(18)F]fluorodopamine (6-[(18)F]FDA), 6-[(18)F]fluoro-l-DOPA (6-[(18)F]FDOPA) and 6-[(18)F]fluoro-m-tyrosine (6-[(18)F]FMT), was evaluated. The originally published base-free method was inoperative. However, a "low base" protocol afforded protected radiolabeled intermediates in radiochemical conversions (RCCs) of 5-18 %. The subsequent deprotection step proceeded almost quantitatively (>95 %). The simple one-pot two-step procedure allowed the preparation of clinical doses of 6-[(18)F]FDA and 6-[(18)F]FDOPA within 50 min (12 and 7 % radiochemical yield, respectively). In an unilateral rat model of Parkinsons disease, 6-[(18)F]FDOPA with high specific activity (175 GBq μmol(-1)) prepared using the described nickel-mediated radiofluorination was compared to 6-[(18)F]FDOPA with low specific activity (30 MBq μmol(-1)) produced via conventional electrophilic radiofluorination. Unexpectedly both tracer variants displayed very similar in vivo properties with respect to signal-to-noise ratio and brain distribution, and consequently, the quality of the obtained PET images was almost identical.
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Affiliation(s)
- Boris D Zlatopolskiy
- Institute of Radiochemistry & Experimental Molecular Imaging, University Clinic CologneKerpener Str. 62, 50937, Cologne, Germany
- Max Planck Institute for Metabolism ResearchGleueler Str. 50, 50931, Cologne, Germany
| | - Johannes Zischler
- Institute of Radiochemistry & Experimental Molecular Imaging, University Clinic CologneKerpener Str. 62, 50937, Cologne, Germany
- Max Planck Institute for Metabolism ResearchGleueler Str. 50, 50931, Cologne, Germany
| | - Elizaveta A Urusova
- Institute of Radiochemistry & Experimental Molecular Imaging, University Clinic CologneKerpener Str. 62, 50937, Cologne, Germany
- Max Planck Institute for Metabolism ResearchGleueler Str. 50, 50931, Cologne, Germany
- Clinic of Nuclear Medicine, RWTH Aachen UniversityPauwelsstraße 30, 52074, Aachen, Germany
| | - Heike Endepols
- Institute of Radiochemistry & Experimental Molecular Imaging, University Clinic CologneKerpener Str. 62, 50937, Cologne, Germany
- Max Planck Institute for Metabolism ResearchGleueler Str. 50, 50931, Cologne, Germany
| | - Elena Kordys
- Institute of Radiochemistry & Experimental Molecular Imaging, University Clinic CologneKerpener Str. 62, 50937, Cologne, Germany
- Max Planck Institute for Metabolism ResearchGleueler Str. 50, 50931, Cologne, Germany
| | - Holm Frauendorf
- Institute of Organic & Biomolecular Chemistry, Georg-August UniversityTammannstr. 2, 37077, Göttingen, Germany
| | - Felix M Mottaghy
- Clinic of Nuclear Medicine, RWTH Aachen UniversityPauwelsstraße 30, 52074, Aachen, Germany
- Department of Nuclear Medicine, Maastricht University Medical CenterPO Box 616, 6200, MD Maastricht, The Netherlands
| | - Bernd Neumaier
- Institute of Radiochemistry & Experimental Molecular Imaging, University Clinic CologneKerpener Str. 62, 50937, Cologne, Germany
- Max Planck Institute for Metabolism ResearchGleueler Str. 50, 50931, Cologne, Germany
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Narendran R, Jedema HP, Lopresti BJ, Mason NS, Himes ML, Bradberry CW. Decreased vesicular monoamine transporter type 2 availability in the striatum following chronic cocaine self-administration in nonhuman primates. Biol Psychiatry 2015; 77:488-92. [PMID: 25062684 PMCID: PMC4275417 DOI: 10.1016/j.biopsych.2014.06.012] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/21/2014] [Revised: 05/13/2014] [Accepted: 06/11/2014] [Indexed: 12/16/2022]
Abstract
BACKGROUND Consistent with postmortem data, in a recent positron emission tomography study, we demonstrated less [(11)C]-(+)-dihydrotetrabenazine ([(11)C]DTBZ) binding to striatal vesicular monoamine transporter type 2 (VMAT2) in cocaine abusers compared with control subjects. A major limitation of these between-group comparison human studies is their inability to establish a causal relationship between cocaine abuse and lower VMAT2. Furthermore, studies in rodents that evaluated VMAT2 binding before and after cocaine self-administration do not support a reduction in VMAT2. METHODS To clarify these discrepant VMAT2 findings and attribute VMAT2 reduction to cocaine abuse, we imaged four rhesus monkeys with [(11)C]DTBZ positron emission tomography before and after 16 months of cocaine self-administration. [(11)C]DTBZ binding potential in the striatum was derived using the simplified reference tissue method with the occipital cortex time activity curve as an input function. RESULTS Chronic cocaine self-administration led to a significant (25.8 ± 7.8%) reduction in [(11)C]DTBZ binding potential. CONCLUSIONS In contrast to the cocaine rodent investigations that do not support alterations in VMAT2, these results in nonhuman primates clearly demonstrated a reduction in VMAT2 binding following prolonged exposure to cocaine. Lower VMAT2 implies that fewer dopamine storage vesicles are available in the presynaptic terminals for release, a likely factor contributing to decreased dopamine transmission in cocaine dependence. Future studies should attempt to clarify the clinical significance of lower VMAT2 in cocaine abusers, for example, its relationship to relapse and vulnerability to mood disorders.
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Affiliation(s)
- Rajesh Narendran
- Department of Radiology; Department of Psychiatry, University of Pittsburgh, Pittsburgh, Pennsylvania.
| | - Hank P. Jedema
- Department of Psychiatry, University of Pittsburgh, Pittsburgh, PA
| | | | | | - Michael L. Himes
- Department of Psychiatry, University of Pittsburgh, Pittsburgh, PA
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Karimi M, Perlmutter JS. The role of dopamine and dopaminergic pathways in dystonia: insights from neuroimaging. TREMOR AND OTHER HYPERKINETIC MOVEMENTS (NEW YORK, N.Y.) 2015; 5:280. [PMID: 25713747 PMCID: PMC4314610 DOI: 10.7916/d8j101xv] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/15/2014] [Accepted: 01/03/2015] [Indexed: 12/14/2022]
Abstract
Background Dystonia constitutes a heterogeneous group of movement abnormalities, characterized by sustained or intermittent muscle contractions causing abnormal postures. Overwhelming data suggest involvement of basal ganglia and dopaminergic pathways in dystonia. In this review, we critically evaluate recent neuroimaging studies that investigate dopamine receptors, endogenous dopamine release, morphology of striatum, and structural or functional connectivity in cortico-basal ganglia-thalamo-cortical and related cerebellar circuits in dystonia. Method A PubMed search was conducted in August 2014. Results Positron emission tomography (PET) imaging offers strong evidence for altered D2/D3 receptor binding and dopaminergic release in many forms of idiopathic dystonia. Functional magnetic resonance imaging (fMRI) and diffusion tensor imaging (DTI) data reveal likely involvement of related cerebello-thalamo-cortical and sensory-motor networks in addition to basal ganglia. Discussion PET imaging of dopamine receptors or transmitter release remains an effective means to investigate dopaminergic pathways, yet may miss factors affecting dopamine homeostasis and related subcellular signaling cascades that could alter the function of these pathways. fMRI and DTI methods may reveal functional or anatomical changes associated with dysfunction of dopamine-mediated pathways. Each of these methods can be used to monitor target engagement for potential new treatments. PET imaging of striatal phosphodiesterase and development of new selective PET radiotracers for dopamine D3-specific receptors and Mechanistic target of rampamycin (mTOR) are crucial to further investigate dopaminergic pathways. A multimodal approach may have the greatest potential, using PET to identify the sites of molecular pathology and magnetic resonance methods to determine their downstream effects.
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Affiliation(s)
- Morvarid Karimi
- Department of Neurology, Washington University in St. Louis, St. Louis, MO, USA
| | - Joel S Perlmutter
- Department of Neurology, Washington University in St. Louis, St. Louis, MO, USA ; Department of Radiology, Neurobiology, Physical Therapy and Occupational Therapy, Washington University in St. Louis, St. Louis, MO, USA
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Sako W, Uluğ AM, Eidelberg D. Functional Imaging to Study Movement Disorders. Mov Disord 2015. [DOI: 10.1016/b978-0-12-405195-9.00012-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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Furukawa Y, Kish SJ. Parkinsonism in GTP cyclohydrolase 1-deficient DOPA-responsive dystonia. Brain 2014; 138:e351. [PMID: 25416181 DOI: 10.1093/brain/awu325] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Yoshiaki Furukawa
- 1 Department of Neurology, Juntendo Tokyo Koto Geriatric Medical Center, Tokyo, Japan 2 Department of Neurology, Faculty of Medicine, University and Postgraduate University of Juntendo, Tokyo, Japan
| | - Stephen J Kish
- 3 Human Brain Laboratory, Research Imaging Centre, Centre for Addiction and Mental Health, Toronto, Ontario, Canada 4 Departments of Psychiatry and Pharmacology, University of Toronto, Toronto, Ontario, Canada
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Abstract
Here, we outline how islet cells use autocrine and paracrine 'circuits' of classical neurotransmitters and their corresponding receptors and transporters to communicate with vicinal β-cells to regulate glucose-stimulated insulin secretion. Many of these same circuits operate in the central nervous system and can be visualized by molecular imaging. We discuss how these techniques might be applied to measuring the dynamics of β-cell function in real time.
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Affiliation(s)
- P E Harris
- Division of Endocrinology, Department of Medicine, The Naomi Berrie Diabetes Center and Columbia University College of Physicians and Surgeons, New York, NY, USA.
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Agarwal PA, Stoessl AJ. Biomarkers for trials of neuroprotection in Parkinson's disease. Mov Disord 2012; 28:71-85. [DOI: 10.1002/mds.25065] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2012] [Revised: 04/19/2012] [Accepted: 04/23/2012] [Indexed: 02/06/2023] Open
Affiliation(s)
- Pankaj A. Agarwal
- Pacific Parkinson's Research Centre; University of British Columbia; Vancouver; British Columbia; Canada
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Abstract
Advances in imaging have made it possible to detect functional and, increasingly, structural changes in Parkinson's disease. Although imaging is not yet routinely used for diagnosis, such an application is becoming increasingly feasible. Of potentially greater interest, however, is the use of imaging as a biomarker to detect premotor disease and disease progression. Imaging also provides insights into complications of Parkinson's disease and its long-term treatment, and the role of dopamine in the normal brain. Furthermore, these techniques can be applied to animal models, to help validate these models and allow their use in the study of potential disease-modifying therapies.
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Affiliation(s)
- A Jon Stoessl
- Pacific Parkinson's Research Centre, University of British Columbia, Vancouver, BC, Canada.
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Abstract
In the last 25 years there have been enormous advances in brain imaging. In addition to utility in diagnosis, these have led to novel insights into the pathogenesis of basal ganglia disease and the role of dopamine and the basal ganglia in normal health. The authors review highlights of this work, with a focus on advances in Parkinson's disease, the dystonias, Huntington's disease, and the role of dopamine in cognition and reward signaling. Emerging areas for future development include studies of functional connectivity, the analysis of default mode networks, studies of novel neurochemical pathways, methods to study disease pathogenesis, and the application of imaging techniques to investigate animal models of disease.
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Affiliation(s)
- A Jon Stoessl
- Pacific Parkinson's Research Centre, University of British Columbia & Vancouver Coastal Health, Vancouver, British Columbia, Canada.
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Abstract
Molecular imaging with PET offers a broad variety of tools supporting the diagnosis of movement disorders. The more widely applied PET imaging techniques have focused on the assessment of neurotransmitter systems, predominantly the pre- and postsynaptic dopaminergic system. Additionally, PET imaging with [(18) F]fluorodeoxyglucose has been extensively used to assess local synaptic activity in the resting state and to highlight local changes in brain metabolism accompanying changes in neural activity in movement disorders. PET imaging has provided us with diagnostic agents as well as tools for evaluation of novel therapeutics, and has served as a powerful means for revealing in vivo changes at different stages of movement disorders and within the course of an individual patient's illness.
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Affiliation(s)
- Valentina Berti
- Department of Clinical Pathophysiology, Nuclear Medicine Unit, University of Florence, Florence, Italy.
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de la Fuente-Fernández R, Appel-Cresswell S, Doudet DJ, Sossi V. Functional neuroimaging in Parkinson's disease. ACTA ACUST UNITED AC 2011; 5:109-20. [PMID: 23480585 DOI: 10.1517/17530059.2011.554820] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
INTRODUCTION Functional neuroimaging techniques have greatly contributed to improving our understanding of Parkinson's disease (PD) neurodegeneration and related compensatory mechanisms. AREAS COVERED In this paper, the authors analyze the role of functional neuroimaging as a diagnostic tool in PD and review functional neuroimaging studies on PD progression and compensatory adaptations. Through this, the article provides the reader with sensible approaches for the use of functional neuroimaging in the diagnosis of PD. The reader is also provided with knowledge on the time course of nigrostriatal dopamine dysfunction in PD as well as an overview of the potential beneficial and deleterious effects of increased dopamine turnover. Finally, the reader is provided with a critical discussion of the differential effects of levodopa and dopamine agonists on presynaptic dopamine markers and the implications for the interpretation of clinical trials. EXPERT OPINION Functional neuroimaging probably plays a limited role in the diagnosis of PD. Parkinson's disease pathology leads to an exponential decline in nigrostriatal dopamine function and a compensatory increase in dopamine turnover, which may help delay symptom onset. On the negative side, increased dopamine turnover contributes to the development of treatment-related motor complications. Presynaptic markers of dopamine function are subject to regulatory changes, compromising the direct interpretation of neuroimaging results in trials of neuroprotective therapies for PD.
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de la Fuente-Fernández R, Schulzer M, Kuramoto L, Cragg J, Ramachandiran N, Au WL, Mak E, McKenzie J, McCormick S, Sossi V, Ruth TJ, Lee CS, Calne DB, Stoessl AJ. Age-specific progression of nigrostriatal dysfunction in Parkinson's disease. Ann Neurol 2011; 69:803-10. [PMID: 21246604 DOI: 10.1002/ana.22284] [Citation(s) in RCA: 179] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2010] [Revised: 08/18/2010] [Accepted: 09/24/2010] [Indexed: 11/06/2022]
Abstract
OBJECTIVE To investigate in vivo the impact of age on nigrostriatal dopamine dysfunction in Parkinson's disease (PD). METHODS PD patients (n = 78) and healthy control subjects (n = 35) underwent longitudinal positron emission tomography assessments using 3 presynaptic dopamine markers: (1) [¹¹C](±)dihydrotetrabenazine (DTBZ), to estimate the density of the vesicular monoamine transporter type 2; (2) [¹¹C]d-threo-methylphenidate, to estimate the density of the plasma membrane dopamine transporter; and (3) 6-[¹⁸F]-fluoro-L-dopa, to estimate the activity of the enzyme dopa-decarboxylase. RESULTS The study comprised 438 PD scans and 241 control scans (679 scans in total). At symptom onset, the loss of putamen DTBZ binding was substantially greater in younger compared to older PD patients (p = 0.015). Remarkably, however, the rate of progression of DTBZ binding loss was significantly slower in younger patients (p < 0.05). The estimated presymptomatic phase of the disease spanned more than 2 decades in younger patients, compared to 1 decade in older patients. INTERPRETATION Our results suggest that, compared to older patients, younger PD patients progress more slowly and are able to endure more damage to the dopaminergic system before the first motor symptoms appear. These observations suggest that younger PD patients have more efficient compensatory mechanisms.
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Abstract
Parkinson's disease (PD) is a common disorder in which the primary features can be related to dopamine deficiency. Changes on structural imaging are limited, but a wealth of abnormalities can be detected using positron emission tomography, single photon emission computed tomography, or functional magnetic resonance imaging to detect changes in neurochemical pathology or functional connectivity. The changes detected on these studies may reflect the disease process itself and/or compensatory responses to the disease, or they may arise in association with disease- and/or treatment-related complications. This review will focus mainly on neurochemical and metabolic studies and reviews various approaches to the assessment of dopaminergic function as well as the function of other neurotransmitters that may be affected in PD. A number of clinical applications are highlighted, including diagnostic utility, identification of preclinical disease, changes associated with motor and nonmotor complications of PD, and the effects of various therapeutic interventions.
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Affiliation(s)
- A Jon Stoessl
- Pacific Parkinson's Research Centre, University of British Columbia & Vancouver Coastal Health, Vancouver, British Columbia, Canada.
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Levodopa and pramipexole effects on presynaptic dopamine PET markers and estimated dopamine release. Eur J Nucl Med Mol Imaging 2010; 37:2364-70. [DOI: 10.1007/s00259-010-1581-3] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2010] [Accepted: 07/23/2010] [Indexed: 02/06/2023]
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Boileau I, Houle S, Rusjan PM, Furukawa Y, Wilkins D, Tong J, Selby P, Wilson AA, Kish SJ. Influence of a low dose of amphetamine on vesicular monoamine transporter binding: a PET (+)[11C]DTBZ study in humans. Synapse 2010; 64:417-20. [PMID: 20169578 DOI: 10.1002/syn.20743] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
We previously reported increased binding of (+)[11C]DTBZ (dihydrotetrabenazine), the vesicular monoamine transporter (VMAT2) positron emission tomography (PET) radioligand, in striatum of some methamphetamine users. This finding might be explained by stimulant-induced vesicular DA depletion resulting in decreased DA (+)[11C]DTBZ competition at VMAT2. In a prospective PET study, we now find that administration of an acute oral dose of amphetamine (0.4 mg/kg) to humans does not cause increased striatal (+)[11C]DTBZ binding but a slight 5% decrease. Our data suggest that a low amphetamine dose is unlikely to cause sufficient DA depletion to detect increased (+)[11C]DTBZ binding and that a higher dose might be required.
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Affiliation(s)
- Isabelle Boileau
- Human Neurochemical Pathology Laboratory, Centre for Addiction and Mental Health, University of Toronto, Toronto, Ontario, Canada.
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Kilbourn MR, Butch ER, Desmond T, Sherman P, Harris PE, Frey KA. In vivo [11C]dihydrotetrabenazine binding in rat striatum: sensitivity to dopamine concentrations. Nucl Med Biol 2009; 37:3-8. [PMID: 20122661 DOI: 10.1016/j.nucmedbio.2009.08.013] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2009] [Revised: 08/28/2009] [Accepted: 08/31/2009] [Indexed: 10/20/2022]
Abstract
INTRODUCTION The sensitivity of the in vivo binding of [(11)C]dihydrotetrabenazine ([(11)C]DTBZ) and [(11)C]methylphenidate ([(11)C]MPH) to their respective targets - vesicular monoamine transporter type 2 (VMAT2) and neuronal membrane dopamine transporter - after alterations in endogenous levels of dopamine was examined in the rat brain. METHODS In vivo binding of [(11)C]DTBZ and [(11)C]MPH was determined using a bolus+infusion protocol. The in vitro number of VMAT2 binding sites was determined by autoradiography. RESULTS Repeated dosing with alpha-methyl-p-tyrosine (AMPT) at doses that significantly (-75%) depleted brain tissue dopamine levels resulted in increased (+36%) in vivo [(11)C]DTBZ binding to VMAT2 in the striatum. The increase in binding could be completely reversed via treatment with L-DOPA/benserazide to restore dopamine levels. There were no changes in the total number of VMAT2 binding sites, as measured using in vitro autoradiography. No changes were observed for in vivo [(11)C]MPH binding to the dopamine transporter in the striatum following AMPT pretreatment. CONCLUSION These results indicate that large reductions in dopamine concentrations in the rat brain can produce modest but significant changes in the binding of radioligands to VMAT2, which can be reversed by replenishment of dopamine using exogenous L-DOPA.
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Affiliation(s)
- Michael R Kilbourn
- Department of Radiology, University of Michigan Medical School, Ann Arbor, MI 48109, USA.
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de la Fuente-Fernández R, Sossi V, McCormick S, Schulzer M, Ruth TJ, Stoessl AJ. Visualizing vesicular dopamine dynamics in Parkinson's disease. Synapse 2009; 63:713-6. [DOI: 10.1002/syn.20653] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Tong J, Wilson AA, Boileau I, Houle S, Kish SJ. Dopamine modulating drugs influence striatal (+)-[11C]DTBZ binding in rats: VMAT2 binding is sensitive to changes in vesicular dopamine concentration. Synapse 2009; 62:873-6. [PMID: 18720517 DOI: 10.1002/syn.20573] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Binding of (+)-[11C]DTBZ (dihydrotetrabenazine) to the striatal vesicular monoamine transporter (VMAT2) is widely considered to be a stable marker of dopamine neurone integrity. However, we now find that specific binding of a tracer dose of (+)-[11C]DTBZ is modestly increased in rat striatum following dopamine depletion with alpha-methyl-p-tyrosine (alpha-MPT, +14%) or d-amphetamine (d-AMPH, 20 mg/kg, +12%) and decreased following dopamine elevation with gamma-hydroxybutyrate (GHB, -16%) or levodopa (-20%). We suggest that in vivo (+)-[11C]DTBZ binding in imaging studies is subject to competition by vesicular dopamine and, in this respect, is not a "stable" dopamine biomarker as is generally assumed.
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Affiliation(s)
- Junchao Tong
- Human Neurochemical Pathology Laboratory, Centre for Addiction and Mental Health, Toronto, Ontario, Canada.
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Increased vesicular monoamine transporter binding during early abstinence in human methamphetamine users: Is VMAT2 a stable dopamine neuron biomarker? J Neurosci 2008; 28:9850-6. [PMID: 18815269 DOI: 10.1523/jneurosci.3008-08.2008] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Animal data indicate that methamphetamine can damage striatal dopamine terminals. Efforts to document dopamine neuron damage in living brain of methamphetamine users have focused on the binding of [(11)C]dihydrotetrabenazine (DTBZ), a vesicular monoamine transporter (VMAT2) positron emission tomography (PET) radioligand, as a stable dopamine neuron biomarker. Previous PET data report a slight decrease in striatal [(11)C]DTBZ binding in human methamphetamine users after prolonged (mean, 3 years) abstinence, suggesting that the reduction would likely be substantial in early abstinence. We measured striatal VMAT2 binding in 16 recently withdrawn (mean, 19 d; range, 1-90 d) methamphetamine users and in 14 healthy matched-control subjects during a PET scan with (+)[(11)C]DTBZ. Unexpectedly, striatal (+)[(11)C]DTBZ binding was increased in methamphetamine users relative to controls (+22%, caudate; +12%, putamen; +11%, ventral striatum). Increased (+)[(11)C]DTBZ binding in caudate was most marked in methamphetamine users abstinent for 1-3 d (+41%), relative to the 7-21 d (+15%) and >21 d (+9%) groups. Above-normal VMAT2 binding in some drug users suggests that any toxic effect of methamphetamine on dopamine neurons might be masked by an increased (+)[(11)C]DTBZ binding and that VMAT2 radioligand binding might not be, as is generally assumed, a "stable" index of dopamine neuron integrity in vivo. One potential explanation for increased (+)[(11)C]DTBZ binding is that VMAT2 binding is sensitive to changes in vesicular dopamine storage levels, presumably low in drug users. If correct, (+)[(11)C]DTBZ might be a useful imaging probe to correlate changes in brain dopamine stores and behavior in users of methamphetamine.
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Collantes M, Peñuelas I, Álvarez-Erviti L, Blesa J, Martí-Climent J, Quincoces G, Delgado M, Ecay M, Martínez A, Arbizu J, Rodríguez-Oroz M, Obeso J, Richter J. Utilización de la 11C-(+)-α-dihidrotetrabenazina para la evaluación de la inervación dopaminérgica en modelos animales de la enfermedad de Parkinson. ACTA ACUST UNITED AC 2008. [DOI: 10.1157/13117191] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Quincoces G, Collantes M, Catalán R, Ecay M, Prieto E, Martino E, Blesa F, Álvarez-Erviti L, Areses P, Arbizu J, Obeso J, Martí-Climent J, Richter J, Peñuelas I. Síntesis rápida y simplificada de 11C-(+)-α-dihidrotetrabenazina para su utilización como radioligando PET de los transportadores vesiculares de monoaminas. ACTA ACUST UNITED AC 2008. [DOI: 10.1157/13114365] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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37
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Abstract
The aberrant expression and function of certain receptors in tumours and other diseased tissues make them preferable targets for molecular imaging. PET and SPECT radionuclides can be used to label specific ligands with high affinity for the target receptors. The functional information obtained from imaging these receptors can be used to better understand the systems under investigation and for diagnostic and therapeutic applications. This review discusses some of the aspects of receptor imaging with small molecule tracers by PET and SPECT and reviews some of the tracers for the receptor imaging of tumours and brain, heart and lung disorders.
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Affiliation(s)
- Aviv Hagooly
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, 510 S. Kingshighway Blvd., Campus Box 8225, St. Louis, MO 63110, USA.
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Kilbourn MR, Butch E, Desmond T, Sherman P, Frey K. Dopamine depletion increases in vivo [11C]DTBZ binding in awake rat brain. Neuroimage 2008. [DOI: 10.1016/j.neuroimage.2008.04.228] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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Murthy R, Harris P, Simpson N, Van Heertum R, Leibel R, Mann JJ, Parsey R. Whole body [11C]-dihydrotetrabenazine imaging of baboons: biodistribution and human radiation dosimetry estimates. Eur J Nucl Med Mol Imaging 2007; 35:790-7. [PMID: 18060547 DOI: 10.1007/s00259-007-0648-2] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2007] [Accepted: 11/04/2007] [Indexed: 10/22/2022]
Abstract
PURPOSE Vesicular monoamine transporter type 2 abundance quantified using the radiotracer [(11)C]-dihydrotetrabenazine (DTBZ) has been used to study diagnosis and pathogenesis of dementia and psychiatric disorders in humans. In addition, it may be a surrogate marker for insulin-producing pancreatic beta cell mass, useful for longitudinal measurements using positron emission tomography to track progression of autoimmune diabetes. To support the feasibility of long-term repeated administrations, we estimate the biodistribution and dosimetry of [(11)C]-DTBZ in humans. METHODS Five baboon studies were acquired using a Siemens ECAT camera. After transmission scanning, 165-210 MBq of [(11)C]-DTBZ were injected, and dynamic whole body emission scans were conducted. Time-activity data were used to obtain residence times and estimate absorbed radiation dose according to the MIRD model. RESULTS Most of the injected tracer localized to the liver and the lungs, followed by the intestines, brain, and kidneys. The highest estimated absorbed radiation dose was in the stomach wall. CONCLUSIONS The largest radiation dose from [(11)C]-DTBZ is to the stomach wall. This dose estimate, as well as the radiation dose to other radiosensitive organs, must be considered in evaluating the risks of multiple administrations.
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Affiliation(s)
- Rajan Murthy
- Department of Psychiatry, Columbia University College of Physicians and Surgeons, New York, NY 10032, USA.
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Abstract
The use of molecular imaging techniques in the central nervous system (CNS) has a rich history. Most of the important developments in imaging-such as computed tomography, magnetic resonance imaging, single photon emission computed tomography, and positron emission tomography-began with neuropsychiatric applications. These techniques and modalities were then found to be useful for imaging other organs involved with various disease processes. Molecular imaging of the CNS has enabled scientists and researchers to understand better the basic biology of brain function and the way in which various disease processes affect the brain. Unlike other organs, the brain is not easily accessible, and it has a highly selective barrier at the endothelial cell level known as the blood-brain barrier. Furthermore, the brain is the most complex cellular network known to exist. Various neurotransmitters act in either an excitatory or an inhibitory fashion on adjacent neurons through a multitude of mechanisms. The various neuronal systems and the myriad of neurotransmitter systems become altered in many diseases. Some of the most devastating diseases, including Alzheimer disease, Parkinson disease, brain tumors, psychiatric disease, and numerous degenerative neurologic diseases, affect only the brain. Molecular neuroimaging will be critical to the future understanding and treatment of these diseases. Molecular neuroimaging of the brain shows tremendous promise for clinical application. In this article, the current state and clinical applications of molecular neuroimaging will be reviewed.
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Affiliation(s)
- Dima A Hammoud
- Department of Radiology, Johns Hopkins University School of Medicine, 1550 Orleans St, CRB-2, Room 492, Baltimore, MD 21231, USA
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Kilbourn MR, Hockley B, Lee L, Hou C, Goswami R, Ponde DE, Kung MP, Kung HF. Pharmacokinetics of [(18)F]fluoroalkyl derivatives of dihydrotetrabenazine in rat and monkey brain. Nucl Med Biol 2007; 34:233-7. [PMID: 17383572 PMCID: PMC1905841 DOI: 10.1016/j.nucmedbio.2007.01.007] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2006] [Revised: 01/18/2007] [Accepted: 01/21/2007] [Indexed: 02/01/2023]
Abstract
The specific binding and regional brain pharmacokinetics of new fluorine-18 ([(18)F])-labeled radioligands for the vesicular monoamine transporter (VMAT2) were examined in the rat and primate brain. In the rat, 9-[(18)F]fluoropropyl-(+/-)-9-O-desmethyldihydrotetrabenazine ([(18)F]FP-(+/-)-DTBZ) showed better specific binding in the striatum than either (+)-[(11)C]dihydrotetrabenazine ((+)-[(11)C]DTBZ) or 9-[(18)F]fluoroethyl-(+/-)-9-O-desmethyldihydrotetrabenazine ([(18)F]FE-(+/-)-DTBZ). Using microPET, the regional brain pharmacokinetics of [(18)F]FE-(+/-)-DTBZ, [(18)F]FP-(+/-)-DTBZ and (+)-[(11)C]DTBZ were examined in the same monkey brain. (+)-[(11)C]DTBZ and [(18)F]FP-(+/-)-DTBZ showed similar brain uptakes and pharmacokinetics, with similar maximum striatum-to-cerebellum ratios (STR/CBL=5.24 and 5.15, respectively) that were significantly better than obtained for [(18)F]FE-(+/-)-DTBZ (STR/CBL=2.55). Striatal distribution volume ratios calculated using Logan plot analysis confirmed the better specific binding for the fluoropropyl compound [distribution volume ratio (DVR)=3.32] vs. the fluoroethyl compound (DVR=2.37). Using the resolved single active isomer of the fluoropropyl compound, [(18)F]FP-(+)-DTBZ, even better specific to nonspecific distribution was obtained, yielding the highest distribution volume ratio (DVR=6.2) yet obtained for a VMAT2 ligand in any species. The binding of [(18)F]FP-(+)-DTBZ to the VMAT2 was shown to be reversible by administration of a competing dose of unlabeled tetrabenazine. Metabolic defluorination was slow and minor for the [(18)F]fluoroalkyl-DTBZ ligands. The characteristics of high specific binding ratio, reversibility, metabolic stability and longer half-life of the radionuclide make [(18)F]FP-(+)-DTBZ a promising alternative VMAT2 radioligand suitable for widespread use in human positron emission tomography studies of monoaminergic innervation of the brain.
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Affiliation(s)
- Michael R Kilbourn
- Department of Radiology, University of Michigan Medical School, Ann Arbor, MI, USA.
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Bohnen NI, Albin RL, Koeppe RA, Wernette KA, Kilbourn MR, Minoshima S, Frey KA. Positron emission tomography of monoaminergic vesicular binding in aging and Parkinson disease. J Cereb Blood Flow Metab 2006; 26:1198-212. [PMID: 16421508 DOI: 10.1038/sj.jcbfm.9600276] [Citation(s) in RCA: 182] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The type-2 vesicular monoamine transporter (VMAT2) might serve as an objective biomarker of Parkinson disease (PD) severity. Thirty-one subjects with early-stage PD and 75 normal subjects underwent continuous intravenous infusion of (+)-[(11)C]dihydrotetrabenazine (DTBZ) and positron emission tomography (PET) imaging to estimate the striatal VMAT2 binding site density with equilibrium tracer modeling. Parkinson disease patients were evaluated clinically in the practically defined 'off' state with the Unified Parkinson Disease Rating Scale (UPDRS), the Hoehn and Yahr Scale (HY), and the Schwab and England Activities of Daily Living Scale (SE). In normal subjects there was age-related decline in striatal DTBZ binding, approximating 0.5% per year. In PD subjects, specific DTBZ binding was reduced in the caudate nucleus (CD; -44%), anterior putamen (-68%), and posterior putamen (PP; -77%). The PP-to-CD ratio of binding was reduced significantly in PD subjects. Dihydrotetrabenazine binding was also reduced by approximately 50% in the PD substantia nigra. Striatal binding reductions correlated significantly with PD duration and SE scores, but not with HY stage or with UPDRS motor subscale (UPDRS(III)) scores. Striatal and midbrain DTBZ binding was asymmetric in PD subjects, with greatest reductions contralateral to the most clinically affected limbs. There was significant correlation between asymmetry of DTBZ binding and clinical asymmetry measured with the UPDRS(III). In HY stage 1 and 1.5 subjects (n=16), PP DTBZ binding contralateral to the clinically unaffected body side was reduced by 73%, indicating substantial preclinical nigrostriatal pathology in PD. We conclude that (+)-[(11)C]DTBZ-PET imaging displays many properties necessary of a PD biomarker.
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Affiliation(s)
- Nicolaas I Bohnen
- Department of Radiology, Division of Nuclear Medicine, The University of Michigan Medical School, Ann Arbor, 48109-0028, USA
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Zheng G, Dwoskin LP, Deaciuc AG, Norrholm SD, Crooks PA. Defunctionalized lobeline analogues: structure-activity of novel ligands for the vesicular monoamine transporter. J Med Chem 2005; 48:5551-60. [PMID: 16107155 PMCID: PMC3617589 DOI: 10.1021/jm0501228] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
(-)-Lobeline (2R,6S,10S), an antagonist at nicotinic acetylcholine receptors (nAChRs), inhibits the neurochemical and behavioral effects of methamphetamine and inhibits dopamine transporter (DAT) and vesicular monoamine transporter (VMAT2) function. VMAT2 is a target for the development of treatments for methamphetamine abuse. Structural modification of lobeline affords the defunctionalized analogues meso-transdiene (MTD) and lobelane, which have high potency and selectivity for VMAT2. To establish the structure-activity relationships within this novel class of VMAT2 ligands, specific stereochemical forms of MTD, lobelane, and other structurally related analogues have been synthesized. These compounds have been evaluated for inhibition of [(3)H]nicotine ([(3)H]NIC) binding (alpha4beta2 nAChR), [(3)H]methyllycaconitine ([(3)H]MLA) binding (alpha7 nAChR), and [(3)H]dihydrotetrabenazine ([(3)H]DTBZ) binding (VMAT2). Generally, all of these analogues had lower affinities at alpha4beta2 and alpha7 nAChRs compared to lobeline, thereby increasing selectivity for VMAT2. The following structural modifications resulted in only modest changes in affinity for VMAT2, affording analogues that were less potent than the lead compound, lobelane: (1) altering the stereochemistry at the C-2 and C-6 positions of the piperidino ring, (2) varying unsaturation in the piperidino C-2 and C-6 substituents, (3) introducing unsaturation into the piperidine ring, (4) ring-opening or eliminating the piperidine ring, and (5) removing the piperidino N-methyl group. Furthermore, incorporating a quaternary ammonium group into defunctionalized lobeline molecules in the cis-series resulted in significant loss of affinity for VMAT2, whereas only a modest change in affinity was obtained in the trans-series. The most potent (K(i) = 630 nM) and VMAT2-selective compound evaluated was the N-methyl-2,6-cis-bis(naphthaleneethyl)piperidine analogue (1-NAP-lobelane), in which the phenyl groups of lobelane were replaced with 1-naphthyl moieties. Thus, initial structure-activity relationship studies reveal that the most promising structural changes to the lobeline molecule that lead to enhancement of VMAT2 affinity and selectivity are defunctionalization, affording lobelane and MTD, and replacement of the phenyl rings of lobelane with other aromatic moieties that have a pi-extended structure.
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Affiliation(s)
| | | | | | | | - Peter A. Crooks
- To whom correspondences should be addressed. Phone: 859-257-1718. Fax: 859-257-7585.
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Anlauf M, Schäfer MKH, Schwark T, von Wurmb-Schwark N, Brand V, Sipos B, Horny HP, Parwaresch R, Hartschuh W, Eiden LE, Klöppel G, Weihe E. Vesicular monoamine transporter 2 (VMAT2) expression in hematopoietic cells and in patients with systemic mastocytosis. J Histochem Cytochem 2005; 54:201-13. [PMID: 16116033 DOI: 10.1369/jhc.5a6739.2005] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Uptake of monoamines into secretory granules is mediated by the vesicular monoamine transporters VMAT1 and VMAT2. In this study, we analyzed their expression in inflammatory and hematopoietic cells and in patients suffering from systemic mastocytosis (SM) and chronic myelogenous leukemia (CML). Normal human and monkey tissue specimens and tissues from patients suffering from SM and CML were analyzed by means of immunohistochemistry, radioactive in situ hybridization, real time RT-PCR, double fluorescence confocal laser scanning microscopy, and immunoelectron microscopy. In normal tissue specimens, VMAT2, but not VMAT1, was expressed in mast cells, megakaryocytes, thrombocytes, basophil granulocytes, and cutaneous Langerhans cells. Further hematopoietic and lymphoid cells showed no expression of VMATs. VMAT2 was expressed in all types of SM, as indicated by coexpression with the mast cell marker tryptase. In CML, VMAT2 expression was retained in neoplastic megakaryocytes and basophil granulocytes. In conclusion, the identification of VMAT2 in mast cells, megakaryocytes, thrombocytes, basophil granulocytes, and cutaneous Langerhans cells provides evidence that these cells possess molecular mechanisms for monoamine storage and handling. VMAT2 identifies normal and neoplastic mast cells, megakaryocytes, and basophil granulocytes and may therefore become a valuable tool for the diagnosis of mastocytosis and malignant systemic diseases involving megakaryocytes and basophil granulocytes.
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MESH Headings
- Animals
- Basophils/metabolism
- Biomarkers, Tumor/biosynthesis
- Blood Platelets/metabolism
- Bone Marrow Cells/metabolism
- Hematopoiesis
- Humans
- Immunohistochemistry
- In Situ Hybridization
- Langerhans Cells/metabolism
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/blood
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/metabolism
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/pathology
- Macaca mulatta
- Mast Cells/metabolism
- Mastocytosis, Systemic/blood
- Mastocytosis, Systemic/metabolism
- Mastocytosis, Systemic/pathology
- Megakaryocytes/metabolism
- Microscopy, Confocal
- Microscopy, Immunoelectron
- Organ Specificity
- RNA, Messenger/biosynthesis
- Reverse Transcriptase Polymerase Chain Reaction
- Vesicular Monoamine Transport Proteins/biosynthesis
- Vesicular Monoamine Transport Proteins/genetics
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Affiliation(s)
- Martin Anlauf
- Department of Pathology, University of Kiel, Michaelisstr. 11, 24105 Kiel, Germany.
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Thobois S, Jahanshahi M, Pinto S, Frackowiak R, Limousin-Dowsey P. PET and SPECT functional imaging studies in Parkinsonian syndromes: from the lesion to its consequences. Neuroimage 2004; 23:1-16. [PMID: 15325346 DOI: 10.1016/j.neuroimage.2004.04.039] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2004] [Revised: 04/23/2004] [Accepted: 04/30/2004] [Indexed: 10/26/2022] Open
Abstract
Functional imaging techniques provide major insights into understanding the pathophysiology, progression, complications, and differential diagnosis of Parkinson's disease (PD). The dopaminergic system has been particularly studied allowing now early, presymptomatic diagnoses, which is of interest for future neuroprotective strategies. The existence of a compensatory hyperactivity of dopa-decarboxylase at disease onset has been recently demonstrated in the nigrostriatal and also extrastriatal dopaminergic pathways. Modification of dopamine receptors expression is observed during PD, but the respective contribution of dopaminergic drugs and the disease process towards these changes is still debated. Abnormalities of cerebral activation are seen and are clearly task-dependent, but the coexistence of hypoactivation in some areas and hyperactivation in others is also now well established. Such hyperactivation may be compensatory but could also reflect an inability to select appropriate motor circuits and inhibit inappropriate ones by PD patients. Interestingly, dopaminergic medications or surgical therapy reverse such abnormalities of brain activation.
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Affiliation(s)
- S Thobois
- Sobell Department of Motor Neurosciences and Movement Disorders, Institute of Neurology, London, UK.
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de la Fuente-Fernández R, Schulzer M, Mak E, Calne DB, Stoessl AJ. Presynaptic mechanisms of motor fluctuations in Parkinson’s disease: a probabilistic model. Brain 2004; 127:888-99. [PMID: 14960500 DOI: 10.1093/brain/awh102] [Citation(s) in RCA: 87] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Levodopa-treated Parkinson's disease is often complicated by the occurrence of motor fluctuations, which can be predictable ('wearing-off') or unpredictable ('on-off'). In contrast, untreated dopa-responsive dystonia (DRD) is usually characterized by predictable diurnal fluctuation. The pathogenesis of motor fluctuations in treated Parkinson's disease and diurnal fluctuation in untreated DRD is poorly understood. We have developed a mathematical model indicating that all these fluctuations in motor function can be explained by presynaptic mechanisms. The model is predicated upon the release of dopamine being subject to probabilistic variations in the quantity of dopamine released by exocytosis of vesicles. Specifically, we propose that the concentration of intravesicular dopamine undergoes dynamic changes according to a log-normal distribution that is associated with different probabilities of release failure. Changes in two parameters, (i) the proportion of vesicles that undergo exocytosis per unit of time and (ii) the proportion of dopamine subject to re-uptake from the synapse, allowed us to model different curves of levodopa response, for the same degree of nigrostriatal damage in Parkinson's disease. The model predicts the following periods of levodopa clinical benefit: 4 h for stable responders, 3 h for wearing-off fluctuators, and 1.5 h for on-off fluctuators. The model also predicts that diurnal fluctuation in untreated DRD should occur some 8 h after getting up in the morning. All these results fit well with clinical observations. Additionally, we calculated the probability of obtaining a second ON period after a single dose of levodopa in Parkinson's disease (the 'yo-yoing' phenomenon). The model shows that the yo-yoing phenomenon depends on how fast the curve crosses the threshold that separates ON and OFF states, which explains why this phenomenon is virtually exclusive to patients with on-off fluctuations. The model supports the idea that presynaptic mechanisms play a key role in both short-duration and long-duration responses encountered in Parkinson's disease. Dyskinesias may also be explained by the same mechanisms.
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Moszczynska A, Fitzmaurice P, Ang L, Kalasinsky KS, Schmunk GA, Peretti FJ, Aiken SS, Wickham DJ, Kish SJ. Why is parkinsonism not a feature of human methamphetamine users? Brain 2004; 127:363-70. [PMID: 14645148 DOI: 10.1093/brain/awh046] [Citation(s) in RCA: 125] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
For more than 50 years, methamphetamine has been a widely used stimulant drug taken to maintain wakefulness and performance and, in high doses, to cause intense euphoria. Animal studies show that methamphetamine can cause short-term and even persistent depletion of brain levels of the neurotransmitter dopamine. However, the clinical features of Parkinson's disease, a dopamine deficiency disorder of the brain, do not appear to be characteristic of human methamphetamine users. We compared dopamine levels in autopsied brain tissue of chronic methamphetamine users with those in patients with Parkinson's disease and in a control group. Mean dopamine levels in the methamphetamine users were reduced more in the caudate (-61%) than in the putamen (-50%), a pattern opposite to that of Parkinson's disease. Some methamphetamine users had severely decreased dopamine levels, within the parkinsonian range, in the caudate (up to 97% dopamine loss) but not in the putamen. As the putamen and caudate subserve aspects of motor and cognitive function, respectively, our data suggest that methamphetamine users are not parkinsonian because dopamine levels are not sufficiently decreased in the motor component of the striatum. However, the near-total reduction in the caudate could explain reports of cognitive disturbances, sometimes disabling, in some drug users, and suggests that treatment with dopamine substitution medication (e.g. levodopa) during drug rehabilitation might be helpful.
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Affiliation(s)
- Anna Moszczynska
- Human Neurochemical Pathology Laboratory, Centre for Addiction and Mental Health, 250 College Street, Toronto, Ontario M5T 1R8, Canada
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