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Feng S, Ge J, Zhao S, Xu Q, Lin H, Li X, Wu J, Guan Y, Zhang T, Zhao S, Zuo C, Shan B, Wu P, Nie B, Yu H, Shi K. Dopaminergic damage pattern predicts phenoconversion time in isolated rapid eye movement sleep behavior disorder. Eur J Nucl Med Mol Imaging 2023; 51:159-167. [PMID: 37668706 DOI: 10.1007/s00259-023-06402-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2023] [Accepted: 08/15/2023] [Indexed: 09/06/2023]
Abstract
PURPOSE The exact phenoconversion time from isolated rapid eye movement (REM) sleep behavior disorder (iRBD) to synucleinopathies remains unpredictable. This study investigated whole-brain dopaminergic damage pattern (DDP) with disease progression and predicted phenoconversion time in individual patients. METHODS Age-matched 33 iRBD patients and 20 healthy controls with 11C-CFT-PET scans were enrolled. The patients were followed up 2-10 (6.7 ± 2.0) years. The phenoconversion year was defined as the base year, and every 2 years before conversion was defined as a stage. Support vector machine with leave-one-out cross-validation strategy was used to perform prediction. RESULTS Dopaminergic degeneration of iRBD was found to occur about 6 years before conversion and then abnormal brain regions gradually expanded. Using DDP, area under curve (AUC) was 0.879 (90% sensitivity and 88.3% specificity) for predicting conversion in 0-2 years, 0.807 (72.7% sensitivity and 83.3% specificity) in 2-4 years, 0.940 (100% sensitivity and 84.6% specificity) in 4-6 years, and 0.879 (100% sensitivity and 80.7% specificity) over 6 years. In individual patients, predicted stages correlated with whole-brain dopaminergic levels (r = - 0.740, p < 0.001). CONCLUSION Our findings suggest that DDP could accurately predict phenoconversion time of individual iRBD patients, which may help to screen patients for early intervention.
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Affiliation(s)
- Shuang Feng
- Beijing Engineering Research Center of Radiographic Techniques and Equipment, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, China
- School of Physics, Zhengzhou University, Zhengzhou, China
| | - Jingjie Ge
- Department of Nuclear Medicine/PET Centre, Huashan Hospital, Shanghai Medical College, Fudan University, Shanghai, China
- National Center for Neurological Disorders & National Research Center for Aging and Medicine, Huashan Hospital, Fudan University, 12 Middle Wulumuqi Road, Jing'an District, Shanghai, China
| | - Shujun Zhao
- School of Physics, Zhengzhou University, Zhengzhou, China
| | - Qian Xu
- Department of Nuclear Medicine/PET Centre, Huashan Hospital, Shanghai Medical College, Fudan University, Shanghai, China
- National Center for Neurological Disorders & National Research Center for Aging and Medicine, Huashan Hospital, Fudan University, 12 Middle Wulumuqi Road, Jing'an District, Shanghai, China
| | - Huamei Lin
- Department of Nuclear Medicine/PET Centre, Huashan Hospital, Shanghai Medical College, Fudan University, Shanghai, China
- National Center for Neurological Disorders & National Research Center for Aging and Medicine, Huashan Hospital, Fudan University, 12 Middle Wulumuqi Road, Jing'an District, Shanghai, China
| | - Xiuming Li
- Department of Nuclear Medicine/PET Centre, Huashan Hospital, Shanghai Medical College, Fudan University, Shanghai, China
- National Center for Neurological Disorders & National Research Center for Aging and Medicine, Huashan Hospital, Fudan University, 12 Middle Wulumuqi Road, Jing'an District, Shanghai, China
| | - Jianjun Wu
- National Center for Neurological Disorders & National Research Center for Aging and Medicine, Huashan Hospital, Fudan University, 12 Middle Wulumuqi Road, Jing'an District, Shanghai, China
- Department of Neurology, Huashan Hospital, Shanghai Medical College, Fudan University, Shanghai, China
| | - Yihui Guan
- Department of Nuclear Medicine/PET Centre, Huashan Hospital, Shanghai Medical College, Fudan University, Shanghai, China
- National Center for Neurological Disorders & National Research Center for Aging and Medicine, Huashan Hospital, Fudan University, 12 Middle Wulumuqi Road, Jing'an District, Shanghai, China
| | - Tianhao Zhang
- Beijing Engineering Research Center of Radiographic Techniques and Equipment, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, China
- School of Nuclear Science and Technology, University of Chinese Academy of Sciences, 19B Yuquan Road, Shijingshan District, Beijing, China
| | - Shilun Zhao
- Beijing Engineering Research Center of Radiographic Techniques and Equipment, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, China
- School of Nuclear Science and Technology, University of Chinese Academy of Sciences, 19B Yuquan Road, Shijingshan District, Beijing, China
| | - Chuantao Zuo
- Department of Nuclear Medicine/PET Centre, Huashan Hospital, Shanghai Medical College, Fudan University, Shanghai, China
- National Center for Neurological Disorders & National Research Center for Aging and Medicine, Huashan Hospital, Fudan University, 12 Middle Wulumuqi Road, Jing'an District, Shanghai, China
| | - Baoci Shan
- Beijing Engineering Research Center of Radiographic Techniques and Equipment, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, China.
- School of Nuclear Science and Technology, University of Chinese Academy of Sciences, 19B Yuquan Road, Shijingshan District, Beijing, China.
| | - Ping Wu
- Department of Nuclear Medicine/PET Centre, Huashan Hospital, Shanghai Medical College, Fudan University, Shanghai, China.
- National Center for Neurological Disorders & National Research Center for Aging and Medicine, Huashan Hospital, Fudan University, 12 Middle Wulumuqi Road, Jing'an District, Shanghai, China.
| | - Binbin Nie
- Beijing Engineering Research Center of Radiographic Techniques and Equipment, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, China.
- School of Nuclear Science and Technology, University of Chinese Academy of Sciences, 19B Yuquan Road, Shijingshan District, Beijing, China.
| | - Huan Yu
- National Center for Neurological Disorders & National Research Center for Aging and Medicine, Huashan Hospital, Fudan University, 12 Middle Wulumuqi Road, Jing'an District, Shanghai, China.
- Department of Neurology, Huashan Hospital, Shanghai Medical College, Fudan University, Shanghai, China.
| | - Kuangyu Shi
- Department of Nuclear Medicine, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
- Computer Aided Medical Procedures, School of Computation, Information and Technology, Technical University of Munich, Munich, Germany
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Lorek K, Mączewska J, Królicki L, Siemiatycka M, Chalimoniuk M, Kisiel-Sajewicz K, Marusiak J. Slowing of EEG waves correlates with striatal [ 18 F]fluorodopa PET/CT uptake and executive dysfunction in Parkinson's disease. Eur J Neurosci 2023; 58:4070-4083. [PMID: 37787445 DOI: 10.1111/ejn.16156] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Revised: 08/30/2023] [Accepted: 09/14/2023] [Indexed: 10/04/2023]
Abstract
Parkinson's disease (PD) research on specific neuroimaging and neurophysiological biomarkers revealing executive dysfunction mechanisms is limited, necessitating validation. Thus, our study aimed to assess associations between electroencephalographic power spectral density (PSD-EEG), striatal [18 F]Fluorodopa uptake and neuropsychological executive function (EF) testing parameters in PD, while also estimating their diagnostic accuracy. We compared resting PSD-EEG, striatal [18 F]Fluorodopa uptake ratios based on positron emission computed tomography ([18 F]FDOPA PET/CT) and neuropsychological EF tests outcomes [Trail Making Test (TMT) and Stroop Test (ST)] between PD patients and healthy controls (HCO) and then calculated correlations among these measures separately for each group. Additionally, we estimated PD diagnostic accuracy of the PSD-EEG and [18 F]FDOPA PET/CT parameters. In PD patients, we observed the following: (i) slower EEG waves, reflected in increased power of the EEG theta and lower-alpha bands in frontal lobe areas; (ii) reduced [18 F]FDOPA PET/CT uptake in the putaminal and caudate nuclei, along with a decreased putamen-to-caudate ratio ([18 F]FDOPA PET/CT PCR); and (iii) longer performance times evident in nearly all EF tests' parameters. Slower EEG waves correlated negatively with [18 F]FDOPA PET/CT PCR and positively with most of the EF test parameters. Furthermore, we found negative correlations between [18 F]FDOPA PET/CT PCR and certain EF measures related to ST. [18 F]FDOPA PET/CT ratios and several PSD-EEG parameters, particularly those from the prefrontal cortex, demonstrated clinically reasonable diagnostic accuracy for PD. In conclusion, EEG waves slowing in the frontal lobe were correlated with striatal dopaminergic deficiency and impaired executive function in mild PD patients and showed promise as a biomarker of PD-related executive dysfunction.
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Affiliation(s)
- Karolina Lorek
- Department of Kinesiology, Faculty of Physiotherapy, Wroclaw University of Health and Sport Science, Wroclaw, Poland
| | - Joanna Mączewska
- Nuclear Medicine Department, Medical University of Warsaw, Warsaw, Poland
| | - Leszek Królicki
- Nuclear Medicine Department, Medical University of Warsaw, Warsaw, Poland
| | - Magdalena Siemiatycka
- Department of Kinesiology, Faculty of Physiotherapy, Wroclaw University of Health and Sport Science, Wroclaw, Poland
| | - Małgorzata Chalimoniuk
- Department of Physical Education and Health in Biala Podlaska, Jozef Pilsudski University of Physical Education in Warsaw, Faculty in Biala Podlaska, Biala Podlaska, Poland
| | - Katarzyna Kisiel-Sajewicz
- Department of Kinesiology, Faculty of Physiotherapy, Wroclaw University of Health and Sport Science, Wroclaw, Poland
| | - Jarosław Marusiak
- Department of Kinesiology, Faculty of Physiotherapy, Wroclaw University of Health and Sport Science, Wroclaw, Poland
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3
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Schneider JS, Kortagere S. Current concepts in treating mild cognitive impairment in Parkinson's disease. Neuropharmacology 2022; 203:108880. [PMID: 34774549 DOI: 10.1016/j.neuropharm.2021.108880] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Revised: 11/05/2021] [Accepted: 11/08/2021] [Indexed: 12/15/2022]
Abstract
Impairment in various aspects of cognition is recognized as an important non-motor symptom of Parkinson's disease (PD). Mild cognitive impairment in PD (PD-MCI) is common in non-demented PD patients and is often associated with severity of motor symptoms, disease duration and increasing age. Further, PD-MCI can have a significant negative effect on performance of daily life activities and may be a harbinger of development of PD dementia. Thus, there is significant interest in developing therapeutic strategies to ameliorate cognitive deficits in PD and improve cognitive functioning of PD patients. However, due to significant questions that remain regarding the pathophysiology of cognitive dysfunction in PD, remediation of cognitive dysfunction in PD has proven difficult. In this paper, we will focus on PD-MCI and will review some of the current therapeutic approaches being taken to try to improve cognitive functioning in patients with PD-MCI.
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Affiliation(s)
- Jay S Schneider
- Dept. of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, PA 19107, USA.
| | - Sandhya Kortagere
- Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, PA 19129, USA
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4
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Hahn A, Reed MB, Pichler V, Michenthaler P, Rischka L, Godbersen GM, Wadsak W, Hacker M, Lanzenberger R. Functional dynamics of dopamine synthesis during monetary reward and punishment processing. J Cereb Blood Flow Metab 2021; 41:2973-2985. [PMID: 34053336 PMCID: PMC8543667 DOI: 10.1177/0271678x211019827] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The assessment of dopamine release with the PET competition model is thoroughly validated but entails disadvantages for the investigation of cognitive processes. We introduce a novel approach incorporating 6-[18F]FDOPA uptake as index of the dynamic regulation of dopamine synthesis enzymes by neuronal firing. The feasibility of this approach is demonstrated by assessing widely described sex differences in dopamine neurotransmission. Reward processing was behaviorally investigated in 36 healthy participants, of whom 16 completed fPET and fMRI during the monetary incentive delay task. A single 50 min fPET acquisition with 6-[18F]FDOPA served to quantify task-specific changes in dopamine synthesis. In men monetary gain induced stronger increases in ventral striatum dopamine synthesis than loss. Interestingly, the opposite effect was discovered in women. These changes were further associated with reward (men) and punishment sensitivity (women). As expected, fMRI showed robust task-specific neuronal activation but no sex difference. Our findings provide a neurobiological basis for known behavioral sex differences in reward and punishment processing, with important implications in psychiatric disorders showing sex-specific prevalence, altered reward processing and dopamine signaling. The high temporal resolution and magnitude of task-specific changes make fPET a promising tool to investigate functional neurotransmitter dynamics during cognitive processing and in brain disorders.
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Affiliation(s)
- Andreas Hahn
- Department of Psychiatry and Psychotherapy, Medical University of Vienna, Vienna, Austria
| | - Murray B Reed
- Department of Psychiatry and Psychotherapy, Medical University of Vienna, Vienna, Austria
| | - Verena Pichler
- Department of Biomedical Imaging and Image-guided Therapy, Division of Nuclear Medicine, Medical University of Vienna, Vienna, Austria.,Department of Pharmaceutical Sciences, Division of Pharmaceutical Chemistry, University of Vienna, Vienna, Austria
| | - Paul Michenthaler
- Department of Psychiatry and Psychotherapy, Medical University of Vienna, Vienna, Austria
| | - Lucas Rischka
- Department of Psychiatry and Psychotherapy, Medical University of Vienna, Vienna, Austria
| | - Godber M Godbersen
- Department of Psychiatry and Psychotherapy, Medical University of Vienna, Vienna, Austria
| | - Wolfgang Wadsak
- Department of Biomedical Imaging and Image-guided Therapy, Division of Nuclear Medicine, Medical University of Vienna, Vienna, Austria.,Center for Biomarker Research in Medicine (CBmed), Graz, Austria
| | - Marcus Hacker
- Department of Biomedical Imaging and Image-guided Therapy, Division of Nuclear Medicine, Medical University of Vienna, Vienna, Austria
| | - Rupert Lanzenberger
- Department of Psychiatry and Psychotherapy, Medical University of Vienna, Vienna, Austria
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5
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Yu HM, Li CY, Liu SW, Yang CH, Chang Y. Copper-mediated nucleophilic radiofluorination of [ 18 F]β-CFT for positron emission tomography imaging of dopamine transporter. J Labelled Comp Radiopharm 2021; 64:228-236. [PMID: 33570188 DOI: 10.1002/jlcr.3905] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Revised: 01/28/2021] [Accepted: 01/29/2021] [Indexed: 11/11/2022]
Abstract
[18 F]β-CFT is a positron emission tomography (PET) ligand for imaging of dopamine transporter. It was proved to be a sensitive PET marker to detect presynaptic dopaminergic hypofunction in Parkinson's disease. In recent years, copper-mediated 18 F-fluorination of aryl boronic esters has been successful in some molecules containing aromatic groups. In this study, we describe the novel synthetic strategy of [18 F]β-CFT by copper-mediated nucleophilic radiofluorination with pinacol-derived aryl boronic esters upon reaction with [18 F]KF/K222 and Cu (OTf)2 (py)4 . The radiolabeling protocol was optimized with [18 F]fluoride elution method and amount of copper catalyst used. [18 F]β-CFT is obtained from boronic ester precursors in 2.2% to 10.6% non-isolated radiochemical yield (RCY). Purified [18 F]β-CFT with >99% radiochemical purity (RCP) and high molar activity was obtained in validation runs. The radiolabeling procedure is straightforward and can easily be adapted for clinical use.
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Affiliation(s)
- Hung-Man Yu
- Isotope Application Division, Institute of Nuclear Energy Research, Taoyuan City, Taiwan
| | - Ching-Yun Li
- Chemistry Division, Institute of Nuclear Energy Research, Taoyuan City, Taiwan
| | - Shiu-Wen Liu
- Chemistry Division, Institute of Nuclear Energy Research, Taoyuan City, Taiwan
| | - Chun-Hung Yang
- Isotope Application Division, Institute of Nuclear Energy Research, Taoyuan City, Taiwan
| | - Yu Chang
- Chemistry Division, Institute of Nuclear Energy Research, Taoyuan City, Taiwan
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6
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Dan X, Liu J, Doyon J, Zhou Y, Ma J, Chan P. Impaired Fine Motor Function of the Asymptomatic Hand in Unilateral Parkinson's Disease. Front Aging Neurosci 2019; 11:266. [PMID: 31636557 PMCID: PMC6787142 DOI: 10.3389/fnagi.2019.00266] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2019] [Accepted: 09/13/2019] [Indexed: 01/05/2023] Open
Abstract
The early detection of Parkinson's disease (PD) still remains a challenge to date. Although studies have previously reported subtle motor function abnormalities in early PD patients, it is unclear whether such clinical signs can be better detected while patients are concurrently performing a cognitive task, and whether they can be useful in predicting patients' clinical conversion state. Seventy-two right-handed participants (40 drug-naive patients with idiopathic unilateral PD and 32 age-matched healthy controls) were enrolled in this study. All participants were asked to perform the Purdue Pegboard test (PPT) either alone (single-task condition) or during a concurrent mental subtraction-by-3 task (dual-task condition). A 4-year telephone follow-up was later conducted to determine whether PD patients converted to bilateral signs. We found that PD patients showed a significant reduction in dexterity on the PPT compared to the controls in both single- and dual-task conditions. Yet patients' performance in the dual-task condition revealed a greater interference effect when patients performed the task with their right hand than with their left hand. PPT also revealed reasonable discriminative ability for prediagnosing PD. However, dual-tasking did not have added value in differentiating early patients and controls. At follow-up, the baseline PPT performance of the asymptomatic hands was positively correlated with time to convert from unilaterally to bilaterally affected states (r = 0.62, P = 0.031). Together, these findings suggest that PPT can serve as a useful auxiliary tool in evaluating early PD, and shed light on the neuroplasticity mechanism of fine motor deficit at this very early stage.
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Affiliation(s)
- Xiaojuan Dan
- Department of Neurology and Neurobiology, Xuanwu Hospital of Capital Medical University, Beijing, China.,Key Laboratory on Neurodegenerative Disorders of Ministry of Education, Key Laboratory on Parkinson's Disease of Beijing, Beijing, China
| | - Jia Liu
- Department of Geriatrics, Xuanwu Hospital of Capital Medical University, Beijing, China
| | - Julien Doyon
- McConnell Brain Imaging Center, Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, QC, Canada
| | - Yongtao Zhou
- Department of Neurology and Neurobiology, Xuanwu Hospital of Capital Medical University, Beijing, China.,Key Laboratory on Neurodegenerative Disorders of Ministry of Education, Key Laboratory on Parkinson's Disease of Beijing, Beijing, China
| | - Jinghong Ma
- Department of Neurology and Neurobiology, Xuanwu Hospital of Capital Medical University, Beijing, China.,Key Laboratory on Neurodegenerative Disorders of Ministry of Education, Key Laboratory on Parkinson's Disease of Beijing, Beijing, China
| | - Piu Chan
- Department of Neurology and Neurobiology, Xuanwu Hospital of Capital Medical University, Beijing, China.,Key Laboratory on Neurodegenerative Disorders of Ministry of Education, Key Laboratory on Parkinson's Disease of Beijing, Beijing, China.,Department of Geriatrics, Xuanwu Hospital of Capital Medical University, Beijing, China.,National Clinical Research Center for Geriatric Disorders, Beijing, China.,Beijing Institute for Brain Disorders Parkinson's Disease Center, Advanced Innovation Center for Human Brain Protection, Capital Medical University, Beijing, China
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7
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Lu E, Sarkar S, Raymick J, Paule MG, Gu Q. Decreased Mcl-1 protein level in the striatum of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-treated mice. Brain Res 2018; 1678:432-439. [DOI: 10.1016/j.brainres.2017.11.014] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2017] [Revised: 11/14/2017] [Accepted: 11/15/2017] [Indexed: 12/15/2022]
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8
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18F-FP-CIT Positron Emission Tomography for Correlating Motor and Cognitive Symptoms of Parkinson's Disease. Dement Neurocogn Disord 2017; 16:57-63. [PMID: 30906372 PMCID: PMC6427982 DOI: 10.12779/dnd.2017.16.3.57] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2017] [Revised: 09/08/2017] [Accepted: 09/08/2017] [Indexed: 11/27/2022] Open
Abstract
Background and Purpose The aim of this paper was to investigate the utility of 18F-N-(3-fluoropropyl)-2β-carboxymethoxy-3β-(4-iodophenyl) nortropane (FP-CIT) positron emission tomography (PET) for evaluating the severity of Parkinson's disease (PD) according to various clinical stages, and to identify the relationship between the striatal substructure and the Unified Parkinson's Disease Rating Scale (UPDRS) motor score, cognitive symptoms through 18F-FP-CIT PET. Methods We retrospectively identified 542 patients with various clinical stages of PD who underwent an 18F-FP-CIT PET at our clinics. The difference between the 18F-FP-CIT PET according to the Hoehn-Yahr stage, correlation between 18F-FP-CIT PET and the UPDRS III grouped motor items, and the Korean Mini-Mental State Examination (K-MMSE) were investigated. Results As disease progressed, the right caudate and both the anterior putamen and caudate/putamen ratios exhibited a significantly lower uptake. The uptake of all striatal substructures was significantly correlated with the UPDRS total motor score. The right caudate nucleus was significantly related to both the UPDRS tremor items and the right UPDRS akinesia-rigidity items. The left caudate nucleus was related to both the UPDRS tremor items and UPDRS akinesia-rigidity items. The right anterior putamen was related to the axial items, right tremor and akinesia-rigidity items; while the left anterior putamen was related to the right tremor and right akinesia-rigidity items. Both of the posterior putamens were related to the axil items, left tremor and left akinesia rigidity items. K-MMSE was not significantly related to any striatal substructures. Conclusions The UPDRS total motor score was significantly correlated with the uptake of all striatal substructures. However, the 18F-FPCIT uptake in specific striatal substructures was rather complexly correlated with the UPDRS motor grouped items and was not significantly related to K-MMSE. These results suggest the possibility of the complex pathophysiology of motor symptoms of PD and limitation of 18F-FPCIT PET for the evaluation of the severity of PD motor and cognitive symptoms.
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Ito H, Kawaguchi H, Kodaka F, Takuwa H, Ikoma Y, Shimada H, Kimura Y, Seki C, Kubo H, Ishii S, Takano H, Suhara T. Normative data of dopaminergic neurotransmission functions in substantia nigra measured with MRI and PET: Neuromelanin, dopamine synthesis, dopamine transporters, and dopamine D2 receptors. Neuroimage 2017; 158:12-17. [DOI: 10.1016/j.neuroimage.2017.06.066] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2017] [Revised: 06/20/2017] [Accepted: 06/23/2017] [Indexed: 10/19/2022] Open
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Stehouwer JS, Goodman MM. Fluorine-18 Radiolabeled PET Tracers for Imaging Monoamine Transporters: Dopamine, Serotonin, and Norepinephrine. PET Clin 2016; 4:101-28. [PMID: 20216936 DOI: 10.1016/j.cpet.2009.05.006] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
This review focuses on the development of fluorine-18 radiolabeled PET tracers for imaging the dopamine transporter (DAT), serotonin transporter (SERT), and norepinephrine transporter (NET). All successful DAT PET tracers reported to date are members of the 3β-phenyl tropane class and are synthesized from cocaine. Currently available carbon-11 SERT PET tracers come from both the diphenylsulfide and 3β-phenyl nortropane class, but so far only the nortropanes have found success with fluorine-18 derivatives. NET imaging has so far employed carbon-11 and fluorine-18 derivatives of reboxetine but due to defluorination of the fluorine-18 derivatives further research is still necessary.
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11
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MRI evaluation of asymmetry of nigrostriatal damage in the early stage of early-onset Parkinson's disease. Parkinsonism Relat Disord 2015; 21:590-6. [DOI: 10.1016/j.parkreldis.2015.03.012] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/14/2014] [Revised: 02/25/2015] [Accepted: 03/09/2015] [Indexed: 11/30/2022]
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12
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Greene JG. Causes and consequences of degeneration of the dorsal motor nucleus of the vagus nerve in Parkinson's disease. Antioxid Redox Signal 2014; 21:649-67. [PMID: 24597973 DOI: 10.1089/ars.2014.5859] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
SIGNIFICANCE Parkinson's disease (PD) is no longer considered merely a movement disorder caused by degeneration of dopamine neurons in the midbrain. It is now recognized as a widespread neuropathological syndrome accompanied by a variety of motor and nonmotor clinical symptoms. As such, any hypothesis concerning PD pathogenesis and pathophysiology must account for the entire spectrum of disease and not solely focus on the dopamine system. RECENT ADVANCES Based on its anatomy and the intrinsic properties of its neurons, the dorsal motor nucleus of the vagus nerve (DMV) is uniquely vulnerable to damage from PD. Fibers in the vagus nerve course throughout the gastrointestinal (GI) tract to and from the brainstem forming a close link between the peripheral and central nervous systems and a point of proximal contact between the environment and areas where PD pathology is believed to start. In addition, DMV neurons are under high levels of oxidative stress due to their high level of α-synuclein expression, fragile axons, and specific neuronal physiology. Moreover, several consequences of DMV damage, namely, GI dysfunction and unrestrained inflammation, may propagate a vicious cycle of injury affecting vulnerable brain regions. CRITICAL ISSUES Current evidence to suggest the vagal system plays a pivotal role in PD pathogenesis is circumstantial, but given the current state of the field, the time is ripe to obtain direct experimental evidence to better delineate it. FUTURE DIRECTIONS Better understanding of the DMV and vagus nerve may provide insight into PD pathogenesis and a neural highway with direct brain access that could be harnessed for novel therapeutic interventions.
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Affiliation(s)
- James G Greene
- Department of Neurology, Emory University , Atlanta, Georgia
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13
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Recent advances in imaging of dopaminergic neurons for evaluation of neuropsychiatric disorders. J Biomed Biotechnol 2012; 2012:259349. [PMID: 22570524 PMCID: PMC3335602 DOI: 10.1155/2012/259349] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2011] [Accepted: 01/27/2012] [Indexed: 12/20/2022] Open
Abstract
Dopamine is the most intensely studied monoaminergic neurotransmitter. Dopaminergic neurotransmission plays an important role in regulating several aspects of basic brain function, including motor, behavior, motivation, and working memory. To date, there are numerous positron emission tomography (PET) and single photon emission computed tomography (SPECT) radiotracers available for targeting different steps in the process of dopaminergic neurotransmission, which permits us to quantify dopaminergic activity in the living human brain. Degeneration of the nigrostriatal dopamine system causes Parkinson's disease (PD) and related Parkinsonism. Dopamine is the neurotransmitter that has been classically associated with the reinforcing effects of drug abuse. Abnormalities within the dopamine system in the brain are involved in the pathophysiology of attention deficit hyperactivity disorder (ADHD). Dopamine receptors play an important role in schizophrenia and the effect of neuroleptics is through blockage of dopamine D2 receptors. This review will concentrate on the radiotracers that have been developed for imaging dopaminergic neurons, describe the clinical aspects in the assessment of neuropsychiatric disorders, and suggest future directions in the diagnosis and management of such disorders.
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Virdee K, Cumming P, Caprioli D, Jupp B, Rominger A, Aigbirhio FI, Fryer TD, Riss PJ, Dalley JW. Applications of positron emission tomography in animal models of neurological and neuropsychiatric disorders. Neurosci Biobehav Rev 2012; 36:1188-216. [PMID: 22342372 DOI: 10.1016/j.neubiorev.2012.01.009] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2011] [Revised: 01/26/2012] [Accepted: 01/31/2012] [Indexed: 01/08/2023]
Abstract
Positron emission tomography (PET) provides dynamic images of the biodistribution of radioactive tracers in the brain. Through application of the principles of compartmental analysis, tracer uptake can be quantified in terms of specific physiological processes such as cerebral blood flow, cerebral metabolic rate, and the availability of receptors in brain. Whereas early PET studies in animal models of brain diseases were hampered by the limited spatial resolution of PET instruments, dedicated small-animal instruments now provide molecular images of rodent brain with resolution approaching 1mm, the theoretic limit of the method. Major applications of PET for brain research have consisted of studies of animal models of neurological disorders, notably Parkinson's disease (PD), Alzheimer's disease (AD), and Huntington's disease (HD), stroke, epilepsy and traumatic brain injury; these studies have particularly benefited from selective neurochemical lesion models (PD), and also transgenic rodent models (AD, HD). Due to their complex and uncertain pathophysiologies, corresponding models of neuropsychiatric disorders have proven more difficult to establish. Historically, there has been an emphasis on PET studies of dopamine transmission, as assessed with a range of tracers targeting dopamine synthesis, plasma membrane transporters, and receptor binding sites. However, notable recent breakthroughs in molecular imaging include the development of greatly improved tracers for subtypes of serotonin, cannabinoid, and metabotropic glutamate receptors, as well as noradrenaline transporters, amyloid-β and neuroinflammatory changes. This article reviews the considerable recent progress in preclinical PET and discusses applications relevant to a number of neurological and neuropsychiatric disorders in humans.
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Affiliation(s)
- Kanwar Virdee
- Behavioural and Clinical Neuroscience Institute, University of Cambridge, Cambridge, CB2 3EB, UK
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Forsback S, Marjamäki P, Eskola O, Bergman J, Rokka J, Grönroos T, Haaparanta M, Solin O. [18F]CFT synthesis and binding to monoamine transporters in rats. EJNMMI Res 2012; 2:3. [PMID: 22277306 PMCID: PMC3299608 DOI: 10.1186/2191-219x-2-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2011] [Accepted: 01/25/2012] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND We present the electrophilic synthesis of [18F]2β-carbomethoxy-3β-(4-fluoro)tropane [[18F]CFT] and the pharmacological specificity and selectivity of [18F]CFT for monoamine transporters in the brain and peripheral organs of rats. The human radiation dose is extrapolated from the animal data. METHODS [18F]CFT was synthesized by electrophilic fluorination of a stannylated precursor by using post-target-produced [18F]F2 as a fluorinating agent. The ex vivo 18F-activity biodistribution of [18F]CFT in the brain of rats was studied by autoradiography. The binding of [18F]CFT to the monoamine transporters was studied using in vivo blocking experiments with dopamine transporter [DAT], norepinephrine transporter [NET], or serotonin transporter [SERT] inhibitors. In vivo animal positron emission tomography was used as a comparative method to determine tracer kinetics. Human radiation dose was assessed using OLINDA software. RESULTS The radiochemical yield of [18F]CFT from the initial [18F]F-, decay corrected to the end of bombardment, was 3.2 ± 1.0%. The specific activity [SA] was 14.5 ± 3.4 GBq/μmol, decay corrected to the end of synthesis. Radiochemical purity exceeded 99%. DAT-specific binding was found in the striatum, locus coeruleus, and pancreas. NET-specific binding was found in the locus coeruleus. SERT-specific binding was not found in any of the studied organs. Effective dose equivalent [EDE] estimated for the standard human model was 12.8 μSv/MBq. Effective dose [ED] was 9.17 μSv/MBq. CONCLUSIONS Post-target-produced high-SA [18F]F2 was used to incorporate18F directly into the phenyl ring of [18F]CFT. The final product had high radiochemical and chemical purities and a high SA for DAT and NET studies in vivo. In periphery, [18F]CFT showed a specific uptake in the pancreas. EDE and ED corresponded well with other18F-radioligands.
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Affiliation(s)
- Sarita Forsback
- Radiopharmaceutical Chemistry Laboratory, Turku PET Centre, University of Turku, Porthaninkatu 3, Turku, 20500, Finland.
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Gallagher CL, Oakes TR, Johnson SC, Chung MK, Holden JE, Bendlin BB, McLaren DG, Xu G, Nickles RJ, Pyzalski R, DeJesus O, Brown WD. Rate of 6-[18F]fluorodopa uptake decline in striatal subregions in Parkinson's disease. Mov Disord 2011; 26:614-20. [PMID: 21449008 DOI: 10.1002/mds.23503] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2010] [Revised: 08/16/2010] [Accepted: 10/03/2010] [Indexed: 11/06/2022] Open
Abstract
BACKGROUND Rate of decline in 6-L-[(18)F]fluorodopa (FDOPA) uptake within the striatum has been reported as showing regional differences in Parkinson's disease (PD). METHODS We acquired longitudinal brain FDOPA positron emission tomography (PET) studies in 26 PD subjects and 11 controls over 4.5 years. We analyzed both spatially normalized voxel-wise maps of radiotracer influx (Kocc) and average Kocc values for six non-overlapping volumes of interest (VOIs) encompassing the striatum. RESULTS The voxel-wise analysis showed that in PD, FDOPA Kocc decline spanned the striatum but was greatest in the posterior putamen ipsilateral and anterior putamen contralateral to initial symptoms. The VOI approached showed that absolute rates of Kocc decline were significantly greater in PD than control subjects, but that the slope of decline did not differ between subregions. In PD, ratios of uptake between subregions did not change during the study with the exception of the ipsilateral putamen/caudate ratio. Decline rates were marginally greater during earlier time segments. Both male gender and advancing age were associated with lower baseline FDOPA uptake, but no difference in decline rates. VOI Kocc values were significantly correlated with disease duration, but only moderately correlated with clinical measures. DISCUSSION We conclude that FDOPA uptake in subregions of the striatum is strongly correlated with disease duration and age, and declines approximately equally from symptom onset in PD. This implies that in idiopathic PD, relative preservation of uptake in the anterior striatum reflects a delay in pathologic involvement of nigrostriatal projections to this region.
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Yagi S, Yoshikawa E, Futatsubashi M, Yokokura M, Yoshihara Y, Torizuka T, Ouchi Y. Progression from Unilateral to Bilateral Parkinsonism in Early Parkinson Disease: Implication of Mesocortical Dopamine Dysfunction by PET. J Nucl Med 2010; 51:1250-7. [DOI: 10.2967/jnumed.110.076802] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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Saiki H, Hayashi T, Takahashi R, Takahashi J. Objective and quantitative evaluation of motor function in a monkey model of Parkinson's disease. J Neurosci Methods 2010; 190:198-204. [DOI: 10.1016/j.jneumeth.2010.05.009] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2010] [Revised: 05/02/2010] [Accepted: 05/11/2010] [Indexed: 11/24/2022]
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Sioka C, Fotopoulos A, Kyritsis AP. Recent advances in PET imaging for evaluation of Parkinson’s disease. Eur J Nucl Med Mol Imaging 2010; 37:1594-603. [DOI: 10.1007/s00259-009-1357-9] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2009] [Accepted: 12/07/2009] [Indexed: 12/20/2022]
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Radiopharmaceuticals for positron emission tomography investigations of Alzheimer’s disease. Eur J Nucl Med Mol Imaging 2009; 37:1575-93. [DOI: 10.1007/s00259-009-1301-z] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2009] [Accepted: 10/09/2009] [Indexed: 12/11/2022]
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21
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In vivo imaging of synaptic function in the central nervous system. Behav Brain Res 2009; 204:1-31. [DOI: 10.1016/j.bbr.2009.06.008] [Citation(s) in RCA: 94] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2009] [Revised: 05/27/2009] [Accepted: 06/02/2009] [Indexed: 01/07/2023]
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Elevated [(18)F]FDOPA utilization in the periaqueductal gray and medial nucleus accumbens of patients with early Parkinson's disease. Neuroimage 2009; 49:2933-9. [PMID: 19941962 DOI: 10.1016/j.neuroimage.2009.11.035] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2009] [Revised: 11/12/2009] [Accepted: 11/13/2009] [Indexed: 11/20/2022] Open
Abstract
PET studies with the DOPA decarboxylase substrate 6-[(18)F]fluoro-l-DOPA (FDOPA) reveal the storage of [(18)F]-fluorodopamine within synaptic vesicles, mainly of dopamine fibres. As such, FDOPA PET is a sensitive indicator of the integrity of the nigrostriatal dopamine innervation. Nonetheless, there have been several reports of focal elevations of FDOPA utilization in brain of patients with Parkinson's disease (PD), all based on reference tissue methods. To investigate this phenomenon further, we used voxel-wise steady-state kinetic analysis to search for regions of elevated FDOPA utilization (K; ml g(-1) min(-1)) and steady-state trapping (V(d); ml g(-1)) in a group of well-characterized patients with early, asymmetric PD, who were contrasted with an age-matched control group. Subtraction of the population mean parametric maps revealed foci of increased FDOPA utilization K (+25%) in the bilateral medial nucleus accumbens, whereas the expected declines in the trapping of FDOPA were seen in the caudate and putamen. This observation suggests hyperfunction of catecholamine fibres innervating specifically the limbic striatum, which could guide the design of future prospective FDOPA-PET studies of the impulse control disorders occurring in some PD patients under treatment with dopamine agonists. A focus of increased FDOPA influx and also V(d) was detected in the periaqueductal grey, consistent with some earlier reports based on reference tissue analysis. Increased FDOPA trapping in the periaqueductal grey of PD patients seems consistent with recent reports of increased activity of serotonin neurons in a rat model of parkinsonism.
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Rinne JO. Positron emission tomography in the differential diagnosis of parkinsonism. J Mov Disord 2009; 2:53-7. [PMID: 24868357 PMCID: PMC4027724 DOI: 10.14802/jmd.09015] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2008] [Accepted: 09/20/2008] [Indexed: 11/24/2022] Open
Abstract
Positron emission tomography (PET) studies on presynaptic dopaminergic function can reveal hypofunction in early Parkinson's disease (PD) which may help in the early diagnosis especially in patients with mild symptoms. This hypofunction can be detected with fluorodopa (reflecting mainly aromatic amino acid decarboxylase activity of nigrostriatal terminals) or dopamine transporter ligands. These studies can also help to distinguish PD from essential tremor. However, investigations of presynaptic dopaminergic function are not useful in the differential diagnosis of parkinsonian syndromes. PET ligands, such as fluorodeoxyglucose (reflecting glucose metabolism) and dopamine receptor ligands, reflecting striatal neuronal function are better in this respect. Cardiac sympathetic function studies represent a new and interesting approach to improve differential diagnosis of parkinsonian syndromes but more studies are needed in larger patient populations with longer follow-up to evaluate the usefulness of these investigations. Multitracer approach combining ligands reflecting different aspects of dopaminergic neurotransmission and other physiological function will increase differential diagnostic accuracy.
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Affiliation(s)
- Juha O Rinne
- Turku PET Centre, University of Turku and Turku University Hospital, Turku, U.K
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24
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Trends in the molecular pathogenesis and clinical therapeutics of common neurodegenerative disorders. Int J Mol Sci 2009; 10:2510-2557. [PMID: 19582217 PMCID: PMC2705504 DOI: 10.3390/ijms10062510] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2009] [Revised: 04/28/2009] [Accepted: 05/05/2009] [Indexed: 12/11/2022] Open
Abstract
The term neurodegenerative disorders, encompasses a variety of underlying conditions, sporadic and/or familial and are characterized by the persistent loss of neuronal subtypes. These disorders can disrupt molecular pathways, synapses, neuronal subpopulations and local circuits in specific brain regions, as well as higher-order neural networks. Abnormal network activities may result in a vicious cycle, further impairing the integrity and functions of neurons and synapses, for example, through aberrant excitation or inhibition. The most common neurodegenerative disorders are Alzheimer’s disease, Parkinson’s disease, Amyotrophic Lateral Sclerosis and Huntington’s disease. The molecular features of these disorders have been extensively researched and various unique neurotherapeutic interventions have been developed. However, there is an enormous coercion to integrate the existing knowledge in order to intensify the reliability with which neurodegenerative disorders can be diagnosed and treated. The objective of this review article is therefore to assimilate these disorders’ in terms of their neuropathology, neurogenetics, etiology, trends in pharmacological treatment, clinical management, and the use of innovative neurotherapeutic interventions.
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Jokinen P, Helenius H, Rauhala E, Brück A, Eskola O, Rinne JO. Simple ratio analysis of 18F-fluorodopa uptake in striatal subregions separates patients with early Parkinson disease from healthy controls. J Nucl Med 2009; 50:893-9. [PMID: 19443601 DOI: 10.2967/jnumed.108.061572] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
UNLABELLED 6-(18)F-fluoro-l-dopa ((18)F-FDOPA) is widely used to investigate dopaminergic hypofunction, for instance, in Parkinson disease (PD). Conventionally, a 90-min scan with either a graphical or a metabolite-purified plasma input approach has been used for quantification. In the clinical setting, to increase compliance, especially in patients with more advanced disease, and to increase the efficacy of tracer and scanner time use, a shorter acquisition and a simple quantitative analysis are desirable. Taking into account the asymmetry of clinical symptoms and the uneven distribution of striatal dopaminergic hypofunction may also improve the use of (18)F-FDOPA PET in early disease detection. Therefore, we compared subregional striatal (18)F-FDOPA PET data from a large group of nonmedicated patients with early PD and a set of healthy elderly volunteers to find out whether a simple ratio approach would reliably separate PD patients from healthy controls. METHODS A total of 89 nonmedicated patients with early PD and 21 healthy volunteers were studied with (18)F-FDOPA PET, and both a region-to-reference (striatal-to-occipital) ratio (SOR) calculated from 75 to 90 min after injection and a graphical analysis of data calculated from 15 to 90 min after (18)F-FDOPA injection (yielding the influx constant [K(i)(ref)]) were used. RESULTS Both SOR and K(i)(ref) values in the PD patients were lowest, relative to those in the healthy controls, in the posterior putamen contralateral to the side with predominant clinical symptoms. The contralateral posterior putamen showed the largest areas under the receiver operating characteristic (ROC) curve-0.994 for SOR and 0.998 for K(i)(ref)-indicating excellent separation of the PD and control groups. The caudate nucleus and the ventral striatum were less impressive in this respect. CONCLUSION A single 15-min scan 75 min after tracer injection seems to be sufficient for separating patients with PD from healthy controls in a clinical research environment. This method represents a powerful and economical alternative for research on the disease mechanism and differential diagnosis.
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Affiliation(s)
- Pekka Jokinen
- Turku PET Centre, Turku University Hospital, University of Turku, Turku, Finland.
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26
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Pattarini R, Rong Y, Qu C, Morgan JI. Distinct mechanisms of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyrimidine resistance revealed by transcriptome mapping in mouse striatum. Neuroscience 2008; 155:1174-94. [PMID: 18675323 PMCID: PMC2632608 DOI: 10.1016/j.neuroscience.2008.06.064] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2008] [Revised: 06/10/2008] [Accepted: 06/20/2008] [Indexed: 12/20/2022]
Abstract
The etiology of idiopathic Parkinson's disease is thought to involve interplay between environmental factors and predisposing genetic traits, although the identification of genetic risk factors remain elusive. The neurotoxicant, 1-methyl-4-phenyl-1,2,3,6-tetrahydropyrimidine (MPTP) produces parkinsonian-like symptoms and pathology in mice and humans. As sensitivity to MPTP is genetically determined in mice this provides an opportunity to identify genes and biological mechanisms that modify the response to an exogenous agent that produces a Parkinson's disease-like condition. MPTP primarily targets dopaminergic nerve terminals in the striatum and elicits changes in striatal gene expression. Therefore, we used Affymetrix and qRT-PCR technology to characterize temporal mRNA changes in striatum in response to MPTP in genetically MPTP-sensitive, C57BL/6J, and MPTP-resistant Swiss Webster and BCL2-associated X protein (Bax)-/- mice. We identified three phases of mRNA expression changes composed of largely distinct gene sets. An early response (5 h) occurred in all strains of mice and multiple brain regions. In contrast, intermediate (24 h) and late (72 h) phases were striatum specific and much reduced in Swiss Webster, indicating these genes contribute and/or are responsive to MPTP-induced pathology. However, Bax-/- mice have robust intermediate responses. We propose a model in which the acute entry of MPP+ into dopaminergic nerve terminals damages them but is insufficient per se to kill the neurons. Rather, we suggest that the compromised nerve terminals elicit longer lasting transcriptional responses in surrounding cells involving production of molecules that feedback on the terminals to cause additional damage that results in cell death. In Swiss Webster, resistance lies upstream in the cascade of events triggered by MPTP and uncouples the acute events elicited by MPTP from the damaging secondary responses. In contrast, in Bax-/- mice resistance lies downstream in the cascade and suggests enhanced tolerance to the secondary insult rather than its attenuation.
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Affiliation(s)
- Roberto Pattarini
- Department of Developmental Neurobiology, St. Jude Children’s Research Hospital, Memphis, TN, 38105
| | - Yongqi Rong
- Department of Developmental Neurobiology, St. Jude Children’s Research Hospital, Memphis, TN, 38105
| | - Chunxu Qu
- Hartwell Center for Bioinformatics and Biotechnology, St. Jude Children’s Research Hospital, Memphis, TN, 38105
| | - James I. Morgan
- Department of Developmental Neurobiology, St. Jude Children’s Research Hospital, Memphis, TN, 38105
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Seibyl JP. Single-photon emission computed tomography and positron emission tomography evaluations of patients with central motor disorders. Semin Nucl Med 2008; 38:274-86. [PMID: 18514083 DOI: 10.1053/j.semnuclmed.2008.03.001] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Neuroimaging biomarkers in movement disorders during the past decade have served as diagnostic agents (Europe), tools for evaluation of novel therapeutics, and a powerful means for describing pathophysiology by revealing in vivo changes at different stages of disease and within the course of an individual patient's illness. As imaging with agents tracking dopaminergic function become more available, the next decade promises to enhance our clinical sophistication in the optimal use of dopaminergic imaging biomarkers for differential diagnosis, characterization of at-risk populations, guiding selection and management of appropriate treatments. The clinical role of these agents as clinical tools goes hand in hand with the development and availability of disease-modifying drugs, which carry the additional requirement for early and accurate diagnosis and improved clinical monitoring once treatment is initiated. Challenges remain in the ideal application of neuroimaging in the clinical algorithms for patient assessment and management. Further, the application of imaging to other targets, both monamineric and nonmonoaminergic, could serve a function beyond the important delineation of pathologic change occurring in patients with Parkinson's disease to suggest some role in improved phenotyping and classification of patients with Parkinson's disease presenting with different symptom clusters. New areas of focus based on the elucidation of mechanisms at the cellular and molecular level, including intense interest in alpha-synuclein and other protein inclusions in neurons and glia, have piqued interest in their in vivo assessment using scinitigraphic methods. Perhaps ultimately, treatment that is targeted to a better delineated pathophysiology-based characterization of movement disorder patients will emerge. The application of neuroimaging biomarkers to multiple ends in movement disorders provides an important model for the multiple roles diagnostic imaging agents can serve in neurodegenerative disorders; for diagnosis, for elaborating pathophysiology in patient populations, for developing new drugs, ultimately for improving clinical management.
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Affiliation(s)
- John P Seibyl
- Institute for Neurodegenerative Disorders, Molecular Neuroimaging, LLC, Yale University School of Medicine, New Haven, CT, USA.
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28
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Musiek ES, Torigian DA, Newberg AB. Investigation of Nonneoplastic Neurologic Disorders with PET and MRI. PET Clin 2008; 3:317-34. [DOI: 10.1016/j.cpet.2009.01.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Rowe JB, Hughes L, Ghosh BCP, Eckstein D, Williams-Gray CH, Fallon S, Barker RA, Owen AM. Parkinson's disease and dopaminergic therapy--differential effects on movement, reward and cognition. ACTA ACUST UNITED AC 2008; 131:2094-105. [PMID: 18577547 PMCID: PMC2494617 DOI: 10.1093/brain/awn112] [Citation(s) in RCA: 146] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Cognitive deficits are very common in Parkinson's disease particularly for ‘executive functions’ associated with frontal cortico-striatal networks. Previous work has identified deficits in tasks that require attentional control like task-switching, and reward-based tasks like gambling or reversal learning. However, there is a complex relationship between the specific cognitive problems faced by an individual patient, their stage of disease and dopaminergic treatment. We used a bimodality continuous performance task during fMRI to examine how patients with Parkinson's disease represent the prospect of reward and switch between competing task rules accordingly. The task-switch was not separately cued but was based on the implicit reward relevance of spatial and verbal dimensions of successive compound stimuli. Nineteen patients were studied in relative ‘on’ and ‘off’ states, induced by dopaminergic medication withdrawal (Hoehn and Yahr stages 1–4). Patients were able to successfully complete the task and establish a bias to one or other dimension in order to gain reward. However the lateral prefrontal cortex and caudate nucleus showed a non-linear U-shape relationship between motor disease severity and regional brain activation. Dopaminergic treatment led to a shift in this U-shape function, supporting the hypothesis of differential neurodegeneration in separate motor and cognitive cortico–striato–thalamo–cortical circuits. In addition, anterior cingulate activation associated with reward expectation declined with more severe disease, whereas activation following actual rewards increased with more severe disease. This may facilitate a change in goal-directed behaviours from deferred predicted rewards to immediate actual rewards, particularly when on dopaminergic treatment. We discuss the implications for investigation and optimal treatment of this common condition at different stages of disease.
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Affiliation(s)
- J B Rowe
- University of Cambridge Department of Clinical Neurosciences, Cambridge, CB2 7EF, UK.
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Antoni G, Långström B. Radiopharmaceuticals: molecular imaging using positron emission tomography. Handb Exp Pharmacol 2008:177-201. [PMID: 18626804 DOI: 10.1007/978-3-540-72718-7_9] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
We describe the use of molecules labeled with short-lived emitting radionuclides for molecular imaging in combination with the positron emission tomography technique. How to use molecular probes to visualize and quantitatively determine rates of specific biochemical events such as synaptic transmission, enzymatic processes and binding to specific receptor proteins is highlighted. The sensitivity of the PET technique and the ability to measure and validate relationships between molecular events and biological functions is a key factor for the successful application of PET in biomedical research. In specific applications, the opportunity of using molecules labeled in specific positions may be critical. Molecular imaging using PET is also gaining increasing interest as a tool in drug development, especially when applied to early proof of concept studies in man. In this chapter, the concept of molecular imaging is exemplified and the use of position-specific labeling of tracer molecules as a tool to gain understanding of complex biological processes will be discussed.
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Affiliation(s)
- Gunnar Antoni
- GE Healthcare Uppsala Imanet AB, P.O. Box 967, 751 09, Uppsala, Sweden.
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Wang J, Zuo CT, Jiang YP, Guan YH, Chen ZP, Xiang JD, Yang LQ, Ding ZT, Wu JJ, Su HL. 18F-FP-CIT PET imaging and SPM analysis of dopamine transporters in Parkinson's disease in various Hoehn & Yahr stages. J Neurol 2007; 254:185-90. [PMID: 17334953 DOI: 10.1007/s00415-006-0322-9] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2006] [Accepted: 06/19/2006] [Indexed: 11/29/2022]
Abstract
To investigate the usefulness of 18F-FP-CIT PET for assessing the severity of Parkinson's disease (PD) at various clinical stages, 41 patients with PD were divided into early (Hoehn&Yahr I-II, n = 23) and advanced (Hoehn & Yahr III-IV, n = 18) subgroups. 18F-FP-CIT PET was performed in these patients and 12 normal subjects. 18F-FP-CIT uptake in striatal subregions and its correlation with UPDRS were first evaluated by ROI analysis, and between-group differences were also analyzed by Statistical Parametric Mapping (SPM). Our results showed that striatal 18F-FP-CIT binding were significantly reduced to 70.9% (caudate), 46.8% (anterior putamen) and 24.0% (posterior putamen) in early PD compared with that of the control, and to 52.0%, 34.5% and 16.5% correspondingly in advanced PD, respectively. There was significant negative correlation between total motor UPDRS score of all parkinsonian patients and 18F-FP-CIT uptake in caudate nucleus (r = -0.53, p < 0.001), anterior putamen (r = -0.53, p < 0.001) and posterior putamen (r = -0.61, p < 0.001). SPM comparison of 18F-FP-CIT uptake between early or advanced PD and the control group showed significant decline in striatum, predominantly localized on the contralateral side and in the dorsal-posterior putamen. These results indicate that 18F-FP-CIT PET can serve as a suitable biomarker to represent the severity of PD in early and advanced stages.
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Affiliation(s)
- Jian Wang
- Department of Neurology, Huashan Hospital affiliated to Fudan University, 12 Wulumuqi Zhong Road, Shanghai 200040, China.
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Pattarini R, Smeyne RJ, Morgan JI. Temporal mRNA profiles of inflammatory mediators in the murine 1-methyl-4-phenyl-1,2,3,6-tetrahydropyrimidine model of Parkinson's disease. Neuroscience 2007; 145:654-68. [PMID: 17258864 PMCID: PMC1894756 DOI: 10.1016/j.neuroscience.2006.12.030] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2006] [Revised: 12/14/2006] [Accepted: 12/16/2006] [Indexed: 12/15/2022]
Abstract
Parkinson's disease (PD) is a neurodegenerative disorder characterized by the loss of dopaminergic neurons in the substantia nigra pars compacta (SNpc). With the exception of a few rare familial forms of the disease, the precise molecular mechanisms underlying PD are unknown. Inflammation is a common finding in the PD brain, but due to the limitation of postmortem analysis its relationship to disease progression cannot be established. However, studies using the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) model of PD have also identified inflammatory responses in the nigrostriatal pathway that precede neuronal degeneration in the SNpc. To assess the pathological relevance of these inflammatory responses and to identify candidate genes that might contribute to neuronal vulnerability, we used quantitative reverse-transcription polymerase chain reaction (qRT-PCR) to measure mRNA levels of 11 cytokine and chemokine encoding genes in the striatum of MPTP-sensitive (C57BL/6J) and MPTP-insensitive (Swiss Webster, SWR) mice following administration of MPTP. The mRNA levels of all 11 genes changed following MPTP treatment, indicating the presence of inflammatory responses in both strains. Furthermore, of the 11 genes examined only 3, interleukin 6 (Il-6), macrophage inflammatory protein 1 alpha/CC chemokine ligand 3 (Mip-1alpha/Ccl3) and macrophage inflammatory protein 1 beta/CC chemokine ligand 4 (Mip-1beta/Ccl4), were differentially regulated between C57BL/6J and SWR mice. In both mouse strains, the level of monocyte chemoattractant protein 1/CC chemokine ligand 2 (Mcp-1/Ccl2) mRNA was the first to increase following MPTP administration, and might represent a key initiating component of the inflammatory response. Using Mcp-1/Ccl2 knockout mice backcrossed onto a C57BL/6J background we found that MPTP-stimulated Mip-1alpha/Ccl3 and Mip-1beta/Ccl4 mRNA expression was significantly lower in the knockout mice; suggesting that Mcp-1/Ccl2 contributes to MPTP-enhanced expression of Mip-1alpha/Ccl3 and Mip-1beta/Ccl4. However, stereological analysis of SNpc neuronal loss in Mcp-1/Ccl2 knockout and wild-type mice showed no differences. These findings suggest that it is the ability of dopaminergic SNpc neurons to survive an inflammatory insult, rather than genetically determined differences in the inflammatory response itself, that underlie the molecular basis of MPTP resistance.
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Affiliation(s)
- R Pattarini
- Department of Developmental Neurobiology, St. Jude Children's Research Hospital, Danny Thomas Research Tower, Room D2025E, Mail Stop 323, Memphis, TN 38105-2794, USA
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Kumakura Y, Gjedde A, Danielsen EH, Christensen S, Cumming P. Dopamine storage capacity in caudate and putamen of patients with early Parkinson's disease: correlation with asymmetry of motor symptoms. J Cereb Blood Flow Metab 2006; 26:358-70. [PMID: 16079784 DOI: 10.1038/sj.jcbfm.9600202] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Conventional graphical analysis of positron emission tomography (PET) recordings of the cerebral uptake of the DOPA decarboxylase substrate [(18)F]fluorodopa (FDOPA) assumes irreversible trapping of [(18)F]fluorodopamine formed in the brain. However, 4-h long PET recordings allow the estimation of a rate constant for elimination of [(18)F]fluorodopamine from the brain (k(loss)), from which can be calculated an effective distribution volume (EDV(1)), which is an index of [(18)F]fluorodopamine storage capacity. We earlier developed a method employing 2-h long FDOPA recordings for the estimation of k(loss) and EDV, here defined as EDV(2). This method is based on subtraction of the calculated brain concentrations of the FDOPA metabolite O-methyl-FDOPA, rather than the subtraction of the entire radioactivity in a reference region. We now extend this method for the parametric mapping of these parameters in the brain of healthy aged volunteers and patients with Parkinson's disease (PD), with asymmetry of motor symptoms. For parametric mapping, we use a novel application of a multilinear solution for the two-tissue compartment FDOPA model. We also test a new application of the Logan graphical analysis for mapping of the FDOPA distribution volume at equilibrium. The estimates of k(loss) and EDV(2) were more sensitive for the discrimination of biochemical abnormality in the putamen of patients with early PD relative to healthy aged subjects, than was the conventional net influx estimate. Of the several methods, multilinear estimates of EDV(2) were most sensitive for discrimination of PD and normal putamen. However, k(loss) was most sensitive for detecting biochemical asymmetry in the putamen of PD patients, and only k(loss) also detected in the caudate of PD patients a decline in the retention of [(18)F]fluorodopamine relative to healthy aged control subjects.
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Dollé F, Emond P, Mavel S, Demphel S, Hinnen F, Mincheva Z, Saba W, Valette H, Chalon S, Halldin C, Helfenbein J, Legaillard J, Madelmont JC, Deloye JB, Bottlaender M, Guilloteau D. Synthesis, radiosynthesis and in vivo preliminary evaluation of [11C]LBT-999, a selective radioligand for the visualisation of the dopamine transporter with PET. Bioorg Med Chem 2006; 14:1115-25. [PMID: 16219467 DOI: 10.1016/j.bmc.2005.09.035] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2005] [Revised: 09/05/2005] [Accepted: 09/13/2005] [Indexed: 10/25/2022]
Abstract
LBT-999 (8-((E)-4-fluoro-but-2-enyl)-3beta-p-tolyl-8-aza-bicyclo[3.2.1]octane-2beta-carboxylic acid methyl ester), a cocaine derivative belonging to a new generation of highly selective dopamine transporter (DAT) ligands, and its corresponding carboxylic acid derivative, the latter used as precursor for labelling both with tritium and the positron-emitter carbon-11 (half-life: 20.38 min), were synthesized from (R)-cocaine. [(3)H]LBT-999 (>99% radiochemically pure, specific radioactivity of 3.1 TBq/mmol) was prepared from [(3)H]methyl iodide, allowing its in vitro pharmacological evaluation (K(D): 9 nM for DAT and IC(50) > 1000 nM for SERT and NET). Routine production batches of 4.5-9.0 GBq of iv injectable solutions of [(11)C]LBT-999 (with specific radioactivities ranging from 30 to 45 GBq/mumol) were prepared in 25-30 min (HPLC purification and formulation included) using the efficient methylation reagent [(11)C]methyl triflate. The preliminary in vivo pharmacological evaluation of [(11)C]LBT-999, using both biodistributions in rats and brain imaging in monkeys with positron emission tomography (PET), clearly illustrates that this ligand is an excellent candidate for quantification with PET of DAT in humans.
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Affiliation(s)
- Frédéric Dollé
- Service Hospitalier Frédéric Joliot, Département de Recherche Médicale, CEA/DSV, Orsay, France.
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Laser literature watch. Photomed Laser Surg 2005; 23:513-24. [PMID: 16262584 DOI: 10.1089/pho.2005.23.513] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Abstract
Functional imaging modalities (positron emission tomography, single photon emission tomography, magnetic resonance spectroscopy, and functional magnetic resonance) allow aspects of regional cerebral function to be evaluated in various neuropsychiatric disorders. This review will summarize the use of such techniques in current imaging studies involving Parkinson's disease and dementia with Lewy bodies, with respect to assessing regional changes, using them in differential diagnosis, and monitoring disease progression and treatment effects.
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Affiliation(s)
- Sean Colloby
- Institute for Ageing and Health, Newcastle University, Wolfson Research Centre, Newcastle General Hospital, Newcastle Upon Tyne, UK
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Abstract
Synucleinopathies comprise a diverse group of neurodegenerative proteinopathies that share common pathological lesions composed of aggregates of conformational and posttranslational modifications of alpha-synuclein in selected populations of neurons and glia. Abnormal filamentous aggregates of misfolded alpha-synuclein protein are the major components of Lewy bodies, dystrophic (Lewy) neurites, and the Papp-Lantos filaments in oligodendroglia and neurons in multiple system atrophy linked to degeneration of affected brain regions. The synucleinopathies include (1) Lewy body disorders and dementia with Lewy bodies, (2) multiple system atrophy (MSA), and (3) Hallervorden-Spatz disease. (1) The pathological diagnosis of Lewy body disorders and dementia with Lewy bodies is established by validated consensus criteria based on semiquantitative assessment of subcortical and cortical Lewy bodies as their common hallmarks. They are accompanied by subcortical multisystem degeneration with neuronal loss and gliosis with or without Alzheimer pathologic state. Lewy bodies also occur in numerous other disorders, including pure autonomic failure, neuroaxonal dystrophies, and various amyloidoses and tauopathies. (2) Multiple system atrophy, a sporadic, adult-onset degenerative movement disorder of unknown cause, is characterized by alpha-synuclein-positive glial cytoplasmic and rare neuronal inclusions throughout the central nervous system associated with striatonigral degeneration, olivopontocerebellar atrophy, and involvement of medullar and spinal autonomic nuclei. (3) In neurodegeneration with brain iron accumulation type I, or Hallervorden-Spatz disease, alpha-synuclein is present in axonal spheroids and glial and neuronal inclusions. While the identity of the major components of Lewy bodies suggests that a pathway leading from normal soluble to abnormal misfolded filamentous proteins is central for their pathogenesis, regardless of the primary disorder, there are conformational differences in alpha-synuclein between neuronal and glial aggregates, showing nonuniform mapping for its epitopes. Despite several cellular and transgenic models, it is not clear whether inclusion body formation is an adaptive/neuroprotective or a pathogenic reaction/process generated in response to different, mostly undetermined, functional triggers linked to neurodegeneration.
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Harada N, Nishiyama S, Satoh K, Fukumoto D, Kakiuchi T, Tsukada H. Age-related changes in the striatal dopaminergic system in the living brain: a multiparametric PET study in conscious monkeys. Synapse 2002; 45:38-45. [PMID: 12112412 DOI: 10.1002/syn.10082] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
In the present study, age-related changes in the striatal dopaminergic system were examined in the living brains of conscious young (6.2 +/- 1.5 years old) and aged (20.2 +/- 2.6 years old) monkeys (Macaca mulatta) using positron emission tomography (PET). L-[beta-(11)C]DOPA and [(11)C]beta-CFT were applied to determine dopamine presynaptic functions such as synthesis rate and transporter (DAT) availability, respectively. Striatal dopamine D(1)- (D(1)R) and D(2)-like receptor (D(2)R) binding were measured with [(11)C]SCH23390 and [(11)C]raclopride, respectively. Although the markers of presynaptic terminals showed parallel age-related declines, the reduction of dopamine synthesis rate measured with L-[beta-(11)C]DOPA was slightly smaller than that of DAT determined with [(11)C]beta-CFT. The binding of [(11)C]raclopride to D(2)R in vivo was significantly reduced with aging, while that of [(11)C]SCH23390 to D(1)R showed no such marked age-related reduction. When the DAT inhibitor GBR12909 (0.5 and 5 mg/kg) was administered, DAT availability, dopamine synthesis, and D(2)R binding were significantly decreased in a dose-dependent manner in both age groups; however, the degrees of the decreases in these parameters were significantly higher in young rather than in aged animals. Dopamine concentration in the striatal extracellular fluid (ECF), as measured by microdialysis, was increased by administration of GBR12909 in a dose-dependent manner and the degree of the increase in dopamine level decreased with age. These results demonstrate that age-related changes of dopamine neuronal functions were not limited to the resting condition but were also seen in the functional responses to the neurotransmitter modulation.
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Affiliation(s)
- Norihiro Harada
- Central Research Laboratory, Hamamatsu Photonics K.K., Shizuoka 434-8601, Japan
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