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Li Q, Hu Q, Tang J, Fang Y, Liu C, Liu J, Qi M, Chen Z, Zhang L. Deuterated [ 18F]fluoroethyl tropane analogs as dopamine transporter probes: Synthesis and biological evaluation. Nucl Med Biol 2023; 118-119:108334. [PMID: 37028197 DOI: 10.1016/j.nucmedbio.2023.108334] [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: 12/15/2022] [Revised: 03/07/2023] [Accepted: 03/21/2023] [Indexed: 03/29/2023]
Abstract
INTRODUCTION The dopamine transporter (DAT) is vitally correlated with Parkinson's disease (PD) and other neurodegenerative diseases. Non-invasive imaging of DAT contributes to early diagnosis and monitoring of related diseases. Recently, we reported a deuterated [18F]fluoroethyl tropane analogue [18F]FECNT-d4 as a potential DAT PET imaging agent. The objective of this work was to extend the investigation by comparing four deuterated [18F]fluoroethyl tropane derivatives ([18F]2a-d) to develop metabolically stable DAT radioligands. METHODS Four fluoroethyl substituted phenyl-tropane compounds 1a-d and deuterated compounds 2a-d were synthesized and their IC50 values to DAT were evaluated. The [18F]fluoroethyl ligands [18F]1a-d and [18F]2a-d were obtained from corresponding labeling precursors by one-step radio-labeling reactions and investigated in terms of lipophilicity and in vitro binding affinity studies. [18F]1d and [18F]2d were then selected for further evaluations by in vivo metabolism study, biodistribution, ex vivo autoradiography, and microPET imaging studies. RESULTS [18F]1a-d and [18F]2a-d were obtained in radiochemical yield of 11-32 % with molar activities of 28-54 GBq/μmol. The 1d and 2d exhibited relatively high affinity to DAT (IC50: 1.9-2.1 nM). Ex vivo autoradiography and microPET studies showed that [18F]2d selectively localized on DAT-rich striatal regions and the specific signal could be blocked by DAT inhibitor. Biodistribution results showed that [18F]2d consistently exhibited a higher ratio of the target to non-target (striatum/cerebellum) than [18F]1d. Furthermore, metabolism study indicated that the in vivo metabolic stability of [18F]2d was superior to that of [18F]1d. CONCLUSION Our findings suggested that the deuterated compound [18F]2d might be a potential probe for DAT PET imaging in the brain.
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Affiliation(s)
- Qingming Li
- Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy, School of Pharmacy, Xuzhou Medical University, Xuzhou 221004, China
| | - Qianyue Hu
- NHC Key Laboratory of Nuclear Medicine, Jiangsu Key Laboratory of Molecular Nuclear Medicine, Jiangsu Institute of Nuclear Medicine, Wuxi 214063, China; Department of Radiopharmaceuticals, School of Pharmacy, Nanjing Medical University, Nanjing 211166, China
| | - Jie Tang
- NHC Key Laboratory of Nuclear Medicine, Jiangsu Key Laboratory of Molecular Nuclear Medicine, Jiangsu Institute of Nuclear Medicine, Wuxi 214063, China
| | - Yi Fang
- NHC Key Laboratory of Nuclear Medicine, Jiangsu Key Laboratory of Molecular Nuclear Medicine, Jiangsu Institute of Nuclear Medicine, Wuxi 214063, China
| | - Chunyi Liu
- NHC Key Laboratory of Nuclear Medicine, Jiangsu Key Laboratory of Molecular Nuclear Medicine, Jiangsu Institute of Nuclear Medicine, Wuxi 214063, China
| | - Jie Liu
- NHC Key Laboratory of Nuclear Medicine, Jiangsu Key Laboratory of Molecular Nuclear Medicine, Jiangsu Institute of Nuclear Medicine, Wuxi 214063, China; Department of Radiopharmaceuticals, School of Pharmacy, Nanjing Medical University, Nanjing 211166, China
| | - Meihui Qi
- NHC Key Laboratory of Nuclear Medicine, Jiangsu Key Laboratory of Molecular Nuclear Medicine, Jiangsu Institute of Nuclear Medicine, Wuxi 214063, China; School of Pharmaceutical Science, Inner Mongolia Medical University, Hohhot 010110, China
| | - Zhengping Chen
- Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy, School of Pharmacy, Xuzhou Medical University, Xuzhou 221004, China; NHC Key Laboratory of Nuclear Medicine, Jiangsu Key Laboratory of Molecular Nuclear Medicine, Jiangsu Institute of Nuclear Medicine, Wuxi 214063, China; Department of Radiopharmaceuticals, School of Pharmacy, Nanjing Medical University, Nanjing 211166, China; School of Pharmaceutical Science, Inner Mongolia Medical University, Hohhot 010110, China.
| | - Ling Zhang
- Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy, School of Pharmacy, Xuzhou Medical University, Xuzhou 221004, China.
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Nisha Aji K, Meyer JH, Rusjan PM, Mizrahi R. Monoamine Oxidase B (MAO-B): A Target for Rational Drug Development in Schizophrenia Using PET Imaging as an Example. ADVANCES IN NEUROBIOLOGY 2023; 30:335-362. [PMID: 36928857 DOI: 10.1007/978-3-031-21054-9_14] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/18/2023]
Abstract
Monoamine oxidase B (MAO-B) is an important high-density enzyme involved in the generation of oxidative stress and central in the catabolism of dopamine, particularly in brain subcortical regions with putative implications in the pathophysiology of schizophrenia. In this chapter, we review postmortem studies, preclinical models, and peripheral and genetic studies implicating MAO-B in psychosis. A literature search in PubMed was conducted and 64 studies were found to be eligible for systematic review. We found that MAO-B could be identified as a potential target in schizophrenia. Evidence comes mostly from studies of peripheral markers, showing reduced platelet MAO-B activity in schizophrenia, together with preclinical results from MAO-B knock-out mice resulting in a hyperdopaminergic state and behavioral disinhibition. However, whether brain MAO-B is altered in vivo in patients with schizophrenia remains unknown. We therefore review methodological studies involving MAO-B positron emission tomography (PET) radioligands used to quantify MAO-B in vivo in the human brain. Given the limitations of currently available treatments for schizophrenia, elucidating whether MAO-B could be used as a target for risk stratification or clinical staging in schizophrenia could allow for a rational search for newer antipsychotics and the development of new treatments.
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Affiliation(s)
- Kankana Nisha Aji
- Douglas Research Centre, Clinical and Translational Sciences Lab, Montreal, QC, Canada
- Department of Pharmacology & Toxicology, University of Toronto, Toronto, ON, Canada
| | - Jeffrey H Meyer
- Department of Pharmacology & Toxicology, University of Toronto, Toronto, ON, Canada
- Department of Psychiatry, University of Toronto, Toronto, ON, Canada
- Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, ON, Canada
| | - Pablo M Rusjan
- Douglas Research Centre, Clinical and Translational Sciences Lab, Montreal, QC, Canada
- Department of Psychiatry, McGill University, Montreal, QC, Canada
| | - Romina Mizrahi
- Douglas Research Centre, Clinical and Translational Sciences Lab, Montreal, QC, Canada.
- Department of Psychiatry, McGill University, Montreal, QC, Canada.
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Xie F, Wei W. [ 64Cu]Cu-ATSM: an emerging theranostic agent for cancer and neuroinflammation. Eur J Nucl Med Mol Imaging 2022; 49:3964-3972. [PMID: 35918492 DOI: 10.1007/s00259-022-05887-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Affiliation(s)
- Fang Xie
- PET Center, Huashan Hospital, Fudan University, Shanghai, 200040, China
| | - Weijun Wei
- Department of Nuclear Medicine, Institute of Clinical Nuclear Medicine, School of Medicine, Renji Hospital, Shanghai Jiao Tong University, Shanghai, 200127, China.
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In vitro and in vivo evaluation of fluorinated indanone derivatives as potential positron emission tomography agents for the imaging of monoamine oxidase B in the brain. Bioorg Med Chem Lett 2021; 48:128254. [PMID: 34256118 DOI: 10.1016/j.bmcl.2021.128254] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Revised: 06/30/2021] [Accepted: 07/05/2021] [Indexed: 12/30/2022]
Abstract
Monoamine oxidases (MAOs) play a key role in the metabolism of major monoamine neurotransmitters. In particular, the upregulation of MAO-B in Parkinson's disease, Alzheimer's disease and cancer augmented the development of selective MAO-B inhibitors for diagnostic and therapeutic purposes, such as the anti-parkinsonian MAO-B irreversible binder l-deprenyl (Selegiline®). Herein we report on the synthesis of novel fluorinated indanone derivatives for PET imaging of MAO-B in the brain. Out of our series, the derivatives 6, 8, 9 and 13 are amongst the most affine and selective ligands for MAO-B reported so far. For the derivative 6-((3-fluorobenzyl)oxy)-2,3-dihydro-1H-inden-1-one (6) exhibiting an outstanding affinity (KiMAO-B = 6 nM), an automated copper-mediated radiofluorination starting from the pinacol boronic ester 17 is described. An in vitro screening in different species revealed a MAO-B region-specific accumulation of [18F]6 in rats and piglets in comparison to L-[3H]deprenyl. The pre-clinical in vivo assessment of [18F]6 in mice demonstrated the potential of indanones to readily cross the blood-brain barrier. Nonetheless, parallel in vivo metabolism studies indicated the presence of blood-brain barrier metabolites, thus arguing for further structural modifications. With the matching analytical profiles of the radiometabolite analysis from the in vitro liver microsome studies and the in vivo evaluation, the structure's elucidation of the blood-brain barrier penetrant radiometabolites is possible and will serve as basis for the development of new indanone derivatives suitable for the PET imaging of MAO-B.
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Xiao H, Choi SR, Zhao R, Ploessl K, Alexoff D, Zhu L, Zha Z, Kung HF. A New Highly Deuterated [ 18F]AV-45, [ 18F]D15FSP, for Imaging β-Amyloid Plaques in the Brain. ACS Med Chem Lett 2021; 12:1086-1092. [PMID: 34267878 DOI: 10.1021/acsmedchemlett.1c00062] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Accepted: 06/17/2021] [Indexed: 12/15/2022] Open
Abstract
[18F]AV-45 (florbetapir f18, Amyvid) is an FDA-approved PET imaging agent targeting Aβ plaques in the brain for diagnosis of Alzheimer's disease (AD). Its metabolites led to a high background in the brain and large bone uptake of [18F]F-, produced from dealkylation of the PEG chain. To slow down the in vivo metabolism, we report the design, synthesis, and evaluation of a highly deuterated derivative, [18F]D15FSP, and compared it with N-methyl-deuterated [18F]D3FSP and nondeuterated [18F]AV-45. D15FSP displayed excellent binding affinity (K i = 7.52 nM) to Aβ aggregates. In vitro autoradiography of [18F]D15FSP, [18F]D3FSP, and [18F]AV-45 showed excellent binding to Aβ plaques in human AD brain sections. Biodistribution studies displayed lower bone uptake at 120 min for [18F]D15FSP compared to that for [18F]D3FSP and [18F]AV-45 (1.44 vs 4.23 and 4.03%ID/g, respectively). As the highly deuterated [18F]D15FSP displayed excellent Aβ binding affinity, high initial brain penetration, and lower bone retention, it might be suitable for PET imaging in detecting Aβ plaques.
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Affiliation(s)
- Hao Xiao
- Beijing Institute of Brain Disorders, Laboratory of Brain Disorders, Ministry of Science and Technology, Collaborative Innovation Center for Brain Disorders, Capital Medical University, Beijing 100069, China
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Seok Rye Choi
- Five Eleven Pharma Inc., Philadelphia, Pennsylvania 19104, United States
| | - Ruiyue Zhao
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
- Key Laboratory of Radiopharmaceuticals, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing 100875, China
| | - Karl Ploessl
- Five Eleven Pharma Inc., Philadelphia, Pennsylvania 19104, United States
| | - David Alexoff
- Five Eleven Pharma Inc., Philadelphia, Pennsylvania 19104, United States
| | - Lin Zhu
- Key Laboratory of Radiopharmaceuticals, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing 100875, China
| | - Zhihao Zha
- Five Eleven Pharma Inc., Philadelphia, Pennsylvania 19104, United States
| | - Hank F. Kung
- Five Eleven Pharma Inc., Philadelphia, Pennsylvania 19104, United States
- Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
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Narayanaswami V, Tong J, Schifani C, Bloomfield PM, Dahl K, Vasdev N. Preclinical Evaluation of TSPO and MAO-B PET Radiotracers in an LPS Model of Neuroinflammation. PET Clin 2021; 16:233-247. [PMID: 33648665 DOI: 10.1016/j.cpet.2020.12.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Discovery of novel PET radiotracers targeting neuroinflammation (microglia and astrocytes) is actively pursued. Employing a lipopolysaccharide (LPS) rat model, this longitudinal study evaluated the translocator protein 18-kDa radiotracer [18F]FEPPA (primarily microglia) and monoamine oxidase B radiotracers [11C]L-deprenyl and [11C]SL25.1188 (astrocytes preferred). Increased [18F]FEPPA binding peaked at 1 week in LPS-injected striatum whereas increased lazabemide-sensitive [11C]L-deprenyl binding developed later. No increase in radiotracer uptake was observed for [11C]SL25.1188. The unilateral intrastriatal LPS rat model may serve as a useful tool for benchmarking PET tracers targeted toward distinct phases of neuroinflammatory reactions involving both microglia and astrocytes.
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Affiliation(s)
- Vidya Narayanaswami
- Azrieli Centre for Neuro-Radiochemistry, Brain Health Imaging Centre, Centre for Addiction and Mental Health, 250 College Street, Room 270, Toronto, Ontario M5T 1R8, Canada
| | - Junchao Tong
- Brain Health Imaging Centre, Centre for Addiction and Mental Health, 250 College Street, Room 339, Toronto, Ontario M5T 1R8, Canada
| | - Christin Schifani
- Brain Health Imaging Centre, Centre for Addiction and Mental Health, 250 College Street, Room 270, Toronto, Ontario M5T 1R8, Canada
| | - Peter M Bloomfield
- Brain Health Imaging Centre, Centre for Addiction and Mental Health, 250 College Street, Room B26A, Toronto, Ontario M5T 1R8, Canada
| | - Kenneth Dahl
- Azrieli Centre for Neuro-Radiochemistry, Brain Health Imaging Centre, Centre for Addiction and Mental Health, 250 College Street, Room B02, Toronto, Ontario M5T 1R8, Canada
| | - Neil Vasdev
- Department of Psychiatry, Brain Health Imaging Centre, Azrieli Centre for Neuro-Radiochemistry, Centre for Addiction and Mental Health, University of Toronto, 250 College Street, Room PET G2, Toronto, Ontario M5T 1R8, Canada.
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Varnäs K, Finnema SJ, Johnström P, Arakawa R, Halldin C, Eriksson LI, Farde L. Effects of sevoflurane anaesthesia on radioligand binding to monoamine oxidase-B in vivo. Br J Anaesth 2020; 126:238-244. [PMID: 33036760 PMCID: PMC8258980 DOI: 10.1016/j.bja.2020.08.052] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Revised: 08/24/2020] [Accepted: 08/31/2020] [Indexed: 11/28/2022] Open
Abstract
Background The molecular actions underlying the clinical effects of inhaled anaesthetics such as sevoflurane and isoflurane are not fully understood. Unexpected observations in positron emission tomography (PET) studies with [11C]AZD9272, a metabotropic glutamate receptor 5 (mGluR5) radioligand with possible affinity for monoamine oxidase-B (MAO-B), suggest that its binding is sensitive to anaesthesia with sevoflurane. The objective of the present study was to assess the effects of sevoflurane anaesthesia on the binding of [11C]AZD9272 and of [11C]L-deprenyl-D2, a radioligand selective for MAO-B in non-human primates (NHPs). Methods Altogether, 12 PET measurements were conducted with a high-resolution research tomograph using the ligands [11C]AZD9272 or [11C]L-deprenyl-D2 in six cynomolgus monkeys anaesthetised with sevoflurane or ketamine/xylazine. Results The specific binding of [11C]AZD9272 and [11C]L-deprenyl-D2 was markedly reduced during anaesthesia with sevoflurane compared with ketamine/xylazine. The reduction was 80–90% (n=3) for [11C]AZD9272 and 77–80% (n=3) for [11C]L-deprenyl-D2. Conclusions Sevoflurane anaesthesia inhibited radioligand binding to MAO-B in the primate brain. The observation of lower MAO-B binding at clinically relevant concentrations of sevoflurane warrants further exploration of the potential role of MAO-B related mechanisms in regulation of systemic blood pressure during anaesthesia.
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Affiliation(s)
- Katarina Varnäs
- Department of Clinical Neuroscience, Center for Psychiatry Research, Karolinska Institutet and Stockholm County Council, Stockholm, Sweden.
| | - Sjoerd J Finnema
- Department of Clinical Neuroscience, Center for Psychiatry Research, Karolinska Institutet and Stockholm County Council, Stockholm, Sweden
| | - Peter Johnström
- Department of Clinical Neuroscience, Center for Psychiatry Research, Karolinska Institutet and Stockholm County Council, Stockholm, Sweden; PET Science Centre, Precision Medicine and Biosamples, R&D Oncology, AstraZeneca, Karolinska Institutet, Stockholm, Sweden
| | - Ryosuke Arakawa
- Department of Clinical Neuroscience, Center for Psychiatry Research, Karolinska Institutet and Stockholm County Council, Stockholm, Sweden
| | - Christer Halldin
- Department of Clinical Neuroscience, Center for Psychiatry Research, Karolinska Institutet and Stockholm County Council, Stockholm, Sweden
| | - Lars I Eriksson
- Perioperative Medicine and Intensive Care, Section for Anesthesiology and Intensive Care Medicine, Karolinska Institutet and Karolinska University Hospital, Stockholm, Sweden
| | - Lars Farde
- Department of Clinical Neuroscience, Center for Psychiatry Research, Karolinska Institutet and Stockholm County Council, Stockholm, Sweden
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Lee SJ, Ko NR, Oh SJ. Optimization of the Synthesis of
18
F‐D
2
‐Deprenyl With Mild
18
F
‐Fluorination and Minimum Precursor Input for
PET
Imaging of Neuroinflammation. B KOREAN CHEM SOC 2020. [DOI: 10.1002/bkcs.12071] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Sang Ju Lee
- Department of Nuclear Medicine, Asan Medical CenterUniversity of Ulsan College of Medicine Seoul 05505 Republic of Korea
| | - Na Re Ko
- Department of Nuclear Medicine, Asan Medical CenterUniversity of Ulsan College of Medicine Seoul 05505 Republic of Korea
- Department of Nuclear MedicineAsan Institute for Life Sciences, Asan Medical Center Seoul 05505 Republic of Korea
| | - Seung Jun Oh
- Department of Nuclear MedicineAsan Institute for Life Sciences, Asan Medical Center Seoul 05505 Republic of Korea
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Albrecht DS, Forsberg A, Sandstrom A, Bergan C, Kadetoff D, Protsenko E, Lampa J, Lee YC, Olgart Höglund C, Catana C, Cervenka S, Akeju O, Lekander M, Cohen G, Halldin C, Taylor N, Kim M, Hooker JM, Edwards RR, Napadow V, Kosek E, Loggia ML. Brain glial activation in fibromyalgia - A multi-site positron emission tomography investigation. Brain Behav Immun 2019; 75:72-83. [PMID: 30223011 PMCID: PMC6541932 DOI: 10.1016/j.bbi.2018.09.018] [Citation(s) in RCA: 171] [Impact Index Per Article: 34.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/27/2018] [Revised: 08/31/2018] [Accepted: 09/13/2018] [Indexed: 12/11/2022] Open
Abstract
Fibromyalgia (FM) is a poorly understood chronic condition characterized by widespread musculoskeletal pain, fatigue, and cognitive difficulties. While mounting evidence suggests a role for neuroinflammation, no study has directly provided evidence of brain glial activation in FM. In this study, we conducted a Positron Emission Tomography (PET) study using [11C]PBR28, which binds to the translocator protein (TSPO), a protein upregulated in activated microglia and astrocytes. To enhance statistical power and generalizability, we combined datasets collected independently at two separate institutions (Massachusetts General Hospital [MGH] and Karolinska Institutet [KI]). In an attempt to disentangle the contributions of different glial cell types to FM, a smaller sample was scanned at KI with [11C]-L-deprenyl-D2 PET, thought to primarily reflect astrocytic (but not microglial) signal. Thirty-one FM patients and 27 healthy controls (HC) were examined using [11C]PBR28 PET. 11 FM patients and 11 HC were scanned using [11C]-L-deprenyl-D2 PET. Standardized uptake values normalized by occipital cortex signal (SUVR) and distribution volume (VT) were computed from the [11C]PBR28 data. [11C]-L-deprenyl-D2 was quantified using λ k3. PET imaging metrics were compared across groups, and when differing across groups, against clinical variables. Compared to HC, FM patients demonstrated widespread cortical elevations, and no decreases, in [11C]PBR28 VT and SUVR, most pronounced in the medial and lateral walls of the frontal and parietal lobes. No regions showed significant group differences in [11C]-L-deprenyl-D2 signal, including those demonstrating elevated [11C]PBR28 signal in patients (p's ≥ 0.53, uncorrected). The elevations in [11C]PBR28 VT and SUVR were correlated both spatially (i.e., were observed in overlapping regions) and, in several areas, also in terms of magnitude. In exploratory, uncorrected analyses, higher subjective ratings of fatigue in FM patients were associated with higher [11C]PBR28 SUVR in the anterior and posterior middle cingulate cortices (p's < 0.03). SUVR was not significantly associated with any other clinical variable. Our work provides the first in vivo evidence supporting a role for glial activation in FM pathophysiology. Given that the elevations in [11C]PBR28 signal were not also accompanied by increased [11C]-L-deprenyl-D2 signal, our data suggests that microglia, but not astrocytes, may be driving the TSPO elevation in these regions. Although [11C]-L-deprenyl-D2 signal was not found to be increased in FM patients, larger studies are needed to further assess the role of possible astrocytic contributions in FM. Overall, our data support glial modulation as a potential therapeutic strategy for FM.
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Affiliation(s)
- Daniel S. Albrecht
- A. A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, United States
| | - Anton Forsberg
- Department of Clinical Neuroscience, Center for Psychiatry Research, Karolinska Institutet, and Stockholm County Council, SE-171 76 Stockholm, Sweden.
| | - Angelica Sandstrom
- Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden,Department of Neuroradiology, Karolinska University Hospital, Stockholm, Sweden
| | - Courtney Bergan
- A. A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, United States
| | - Diana Kadetoff
- Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden; Department of Neuroradiology, Karolinska University Hospital, Stockholm, Sweden; Stockholm Spine Center, Stockholm, Sweden.
| | - Ekaterina Protsenko
- A. A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, United States.
| | - Jon Lampa
- Rheumatology Unit, Department of Medicine, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden.
| | - Yvonne C. Lee
- Division of Rheumatology, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, United States,Division of Rheumatology, Northwestern University Feinberg School of Medicine, Chicago, IL, United States
| | | | - Ciprian Catana
- A. A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, United States.
| | - Simon Cervenka
- Department of Clinical Neuroscience, Center for Psychiatry Research, Karolinska Institutet, and Stockholm County Council, SE-171 76 Stockholm, Sweden.
| | - Oluwaseun Akeju
- Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA, United States.
| | - Mats Lekander
- Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden; Department of Neuroradiology, Karolinska University Hospital, Stockholm, Sweden; Stress Research Institute, Stockholm University, Stockholm, Sweden.
| | - George Cohen
- Department of Rheumatology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, United States.
| | - Christer Halldin
- Department of Clinical Neuroscience, Center for Psychiatry Research, Karolinska Institutet, and Stockholm County Council, SE-171 76 Stockholm, Sweden.
| | - Norman Taylor
- Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA, United States.
| | | | | | | | - Vitaly Napadow
- A. A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, United States; Department of Anesthesiology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, United States.
| | - Eva Kosek
- Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden; Department of Neuroradiology, Karolinska University Hospital, Stockholm, Sweden; Stockholm Spine Center, Stockholm, Sweden.
| | - Marco L. Loggia
- A. A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, United States
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Liu F, Choi SR, Zha Z, Ploessl K, Zhu L, Kung HF. Deuterated 18F-9-O-hexadeutero-3-fluoropropoxyl-(+)-dihydrotetrabenazine (D6-FP-(+)-DTBZ): A vesicular monoamine transporter 2 (VMAT2) imaging agent. Nucl Med Biol 2017; 57:42-49. [PMID: 29306111 DOI: 10.1016/j.nucmedbio.2017.11.009] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2017] [Revised: 11/21/2017] [Accepted: 11/28/2017] [Indexed: 11/19/2022]
Abstract
INTRODUCTION Vesicular monoamine transporters 2 (VMAT2) in the brain serve as transporter for packaging monoamine in vesicles for normal CNS neurotransmission. Several VMAT2 imaging agents, [11C]-(+)-DTBZ, dihydrotetrabenazine and [18F]FP-(+)-DTBZ (9-O-fluoropropyl-(+)-dihydro tetrabenazine, a.k.a. [18F]AV-133), are useful for studying the changes in brain function related to monoamine transmission by in vivo imaging. Deuterated analogs have been reported targeting VMAT2 binding sites. METHODS A novel deuterated [18F]9-O-hexaduterofluoropropyl-(+)-dihydrotetrabenazine, [18F]D6-FP-(+)-DTBZ, [18F]1, was prepared as a VMAT2 imaging agent. This 18F agent which targeted VMAT2 was evaluated by in vitro binding, in vivo biodistribution and microPET imaging studies in rodents. RESULTS The one step radiolabeling reaction led to the desired [18F]D6-FP-(+)-DTBZ, [18F]1, which showed excellent binding affinity to VMAT2 (Ki=0.32±0.07nM) comparable to that of FP-(+)-DTBZ (Ki=0.33±0.02nM) using [18F]FP-(+)-DTBZ and rat striatum membrane homogenates. In vivo biodistribution in normal rats showed that 1, exhibited excellent brain uptake and comparable high ratio of striatum to cerebellum (target/background) ratio at 1h after injection (ratio of 6.05±0.43 vs 5.66±0.72 for [18F]FP-(+)-DTBZ vs [18F]1, respectively). MicroPET imaging studies in rats further confirm that the striatum with high VMAT2 concentration was clearly delineated in normal rat brain after iv injection of [18F]1. We observed minor changes of metabolism in rat plasma between these two agents; however, the changes showed little effect on regional brain uptake and retention. CONCLUSIONS The results reported here lend support for using [18F]D6-FP-(+)-DTBZ, [18F]1, as in vivo PET imaging agent for VMAT2 binding in the brain.
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Affiliation(s)
- Futao Liu
- Key Laboratory of Radiopharmaceuticals, Beijing Normal University, Ministry of Education, Beijing 100875, PR China; Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Seok Rye Choi
- Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104, USA; Five Eleven Pharma Inc., Philadelphia, PA 19104, USA
| | - Zhihao Zha
- Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Karl Ploessl
- Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104, USA; Five Eleven Pharma Inc., Philadelphia, PA 19104, USA
| | - Lin Zhu
- Key Laboratory of Radiopharmaceuticals, Beijing Normal University, Ministry of Education, Beijing 100875, PR China; Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Hank F Kung
- Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104, USA; Five Eleven Pharma Inc., Philadelphia, PA 19104, USA.
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Heurling K, Leuzy A, Jonasson M, Frick A, Zimmer ER, Nordberg A, Lubberink M. Quantitative positron emission tomography in brain research. Brain Res 2017; 1670:220-234. [PMID: 28652218 DOI: 10.1016/j.brainres.2017.06.022] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2017] [Revised: 06/19/2017] [Accepted: 06/20/2017] [Indexed: 12/21/2022]
Abstract
The application of positron emission tomography (PET) in brain research has increased substantially during the past 20years, and is still growing. PET provides a unique insight into physiological and pathological processes in vivo. In this article we introduce the fundamentals of PET, and the methods available for acquiring quantitative estimates of the parameters of interest. A short introduction to different areas of application is also given, including basic research of brain function and in neurology, psychiatry, drug receptor occupancy studies, and its application in diagnostics of neurodegenerative disorders such as Alzheimer's disease and Parkinson's disease. Our aim is to inform the unfamiliar reader of the underlying basics and potential applications of PET, hoping to inspire the reader into considering how the technique could be of benefit for his or her own research.
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Affiliation(s)
- Kerstin Heurling
- Wallenberg Centre for Molecular and Translational Medicine and the Department of Psychiatry and Neurochemistry, University of Gothenburg, Sweden; Department of Surgical Sciences, Uppsala University, Uppsala, Sweden.
| | - Antoine Leuzy
- Department Neurobiology, Care Sciences and Society, Division of Translational Alzheimer Neurobiology, Karolinska Institutet, Stockholm, Sweden
| | - My Jonasson
- Department of Surgical Sciences, Uppsala University, Uppsala, Sweden; Medical Physics, Uppsala University Hospital, Uppsala, Sweden
| | - Andreas Frick
- Department of Psychology, Uppsala University, Uppsala, Sweden; Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Eduardo R Zimmer
- Department of Biochemistry, Federal University of Rio Grande do Sul, Porto Alegre, Brazil; Brain Institute of Rio Grande do Sul (BraIns), Pontifical Catholic University of Rio Grande do Sul, Porto Alegre, Brazil
| | - Agneta Nordberg
- Department Neurobiology, Care Sciences and Society, Division of Translational Alzheimer Neurobiology, Karolinska Institutet, Stockholm, Sweden; Department of Geriatric Medicine, Karolinska University Hospital Huddinge, Stockholm, Sweden
| | - Mark Lubberink
- Department of Surgical Sciences, Uppsala University, Uppsala, Sweden; Medical Physics, Uppsala University Hospital, Uppsala, Sweden
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Arakawa R, Stenkrona P, Takano A, Nag S, Maior RS, Halldin C. Test-retest reproducibility of [ 11C]-L-deprenyl-D 2 binding to MAO-B in the human brain. EJNMMI Res 2017. [PMID: 28634836 PMCID: PMC5478550 DOI: 10.1186/s13550-017-0301-4] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Background [11C]-l-deprenyl-D2 is a positron emission tomography (PET) radioligand for measurement of the monoamine oxidase B (MAO-B) activity in vivo brain. The estimation of the test-retest reproducibility is important for accurate interpretation of PET studies. Results We performed two [11C]-l-deprenyl-D2 scans for six healthy subjects and evaluated the test-retest variability of this radioligand. MAO-B binding was quantified by two tissue compartment model (2TCM) with three rate constants (K1, k2, k3) using metabolite-corrected plasma radioactivity. The λk3 defined as (K1/k2) × k3 was also calculated. The correlation between MAO-B binding and age, and the effect of partial volume effect correction (PVEc) for the reproducibility were also estimated. %difference of k3 was 2.6% (medial frontal cortex) to 10.3% (hippocampus), and that of λk3 was 5.0% (thalamus) to 9.2% (cerebellum). Mean %difference of all regions were 5.3 and 7.0% in k3 and λk3, respectively. All regions showed below 10% variabilities except the hippocampus in k3 (10.3%). Intraclass correlation coefficient (ICC) of k3 was 0.78 (hippocampus) to 0.98 (medial frontal cortex), and that of λk3 was 0.78 (hippocampus) to 0.95 (thalamus). Mean ICC were 0.94 and 0.89 in k3 and λk3, respectively. The highest positive correlation with age was observed in the hippocampus, as r = 0.75 in k3 and 0.76 in λk3. After PVEc, mean %difference were 5.6 and 7.2% in k3 and λk3, respectively. Mean ICC were 0.92 and 0.90 for k3 and λk3, respectively. These values were almost the same as those before PVEc. Conclusions The present results indicate that k3 and λk3 of [11C]-l-deprenyl-D2 are reliable parameters for test-retest reproducibility with healthy subjects both before and after PVEc. The studies with patients of larger sample size are required for further clinical applications.
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Affiliation(s)
- Ryosuke Arakawa
- Department of Clinical Neuroscience, Center for Psychiatry Research, Karolinska Institutet and Stockholm County Council, Stockholm, Sweden.
| | - Per Stenkrona
- Department of Clinical Neuroscience, Center for Psychiatry Research, Karolinska Institutet and Stockholm County Council, Stockholm, Sweden
| | - Akihiro Takano
- Department of Clinical Neuroscience, Center for Psychiatry Research, Karolinska Institutet and Stockholm County Council, Stockholm, Sweden
| | - Sangram Nag
- Department of Clinical Neuroscience, Center for Psychiatry Research, Karolinska Institutet and Stockholm County Council, Stockholm, Sweden
| | - Rafael S Maior
- Department of Clinical Neuroscience, Center for Psychiatry Research, Karolinska Institutet and Stockholm County Council, Stockholm, Sweden.,Primate Center and Laboratory of Neurosciences and Behavior, Department of Physiological Sciences, Institute of Biology, University of Brasilia, Brasilia, Brazil
| | - Christer Halldin
- Department of Clinical Neuroscience, Center for Psychiatry Research, Karolinska Institutet and Stockholm County Council, Stockholm, Sweden
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Ng KP, Pascoal TA, Mathotaarachchi S, Therriault J, Kang MS, Shin M, Guiot MC, Guo Q, Harada R, Comley RA, Massarweh G, Soucy JP, Okamura N, Gauthier S, Rosa-Neto P. Monoamine oxidase B inhibitor, selegiline, reduces 18F-THK5351 uptake in the human brain. ALZHEIMERS RESEARCH & THERAPY 2017; 9:25. [PMID: 28359327 PMCID: PMC5374697 DOI: 10.1186/s13195-017-0253-y] [Citation(s) in RCA: 243] [Impact Index Per Article: 34.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Accepted: 03/01/2017] [Indexed: 01/19/2023]
Abstract
Background 18F-THK5351 is a quinoline-derived tau imaging agent with high affinity to paired helical filaments (PHF). However, high levels of 18F-THK5351 retention in brain regions thought to contain negligible concentrations of PHF raise questions about the interpretation of the positron emission tomography (PET) signals, particularly given previously described interactions between quinolone derivatives and monoamine oxidase B (MAO-B). Here, we tested the effects of MAO-B inhibition on 18F-THK5351 brain uptake using PET and autoradiography. Methods Eight participants (five mild cognitive impairment, two Alzheimer’s disease, and one progressive supranuclear palsy) had baseline 18F-AZD4694 and 18F-THK5351 scans in order to quantify brain amyloid and PHF load, respectively. A second 18F-THK5351 scan was conducted 1 week later, 1 h after a 10-mg oral dose of selegiline. Three out of eight patients also had a third 18F-THK5351 scan 9–28 days after the selegiline administration. The primary outcome measure was standardized uptake value (SUV), calculated using tissue radioactivity concentration from 50 to 70 min after 18F-THK5351 injection, normalizing for body weight and injected radioactivity. The SUV ratio (SUVR) was determined using the cerebellar cortex as the reference region. 18F-THK5351 competition autoradiography studies in postmortem tissue were conducted using 150 and 500 nM selegiline. Results At baseline, 18F-THK5351 SUVs were highest in the basal ganglia (0.64 ± 0.11) and thalamus (0.62 ± 0.14). In the post-selegiline scans, the regional SUVs were reduced on average by 36.7% to 51.8%, with the greatest reduction noted in the thalamus (51.8%) and basal ganglia (51.4%). MAO-B inhibition also reduced 18F-THK5351 SUVs in the cerebellar cortex (41.6%). The SUVs remained reduced in the three patients imaged at 9–28 days. Tissue autoradiography confirmed the effects of MAO-B inhibition on 18F-THK5351 uptake. Conclusions These results indicate that the interpretation of 18F-THK5351 PET images, with respect to tau, is confounded by the high MAO-B availability across the entire brain. In addition, the heterogeneous MAO-B availability across the cortex may limit the interpretation of 18F-THK5351 scans using reference region methods.
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Affiliation(s)
- Kok Pin Ng
- Translational Neuroimaging Laboratory, The McGill University Research Centre for Studies in Aging, 6825 LaSalle Boulevard, Verdun, Québec, H4H 1R3, Canada.,Department of Neurology, National Neuroscience Institute, 11 Jalan Tan Tock Seng, Singapore, 308433, Singapore.,Alzheimer's Disease Research Unit, The McGill University Research Centre for Studies in Aging, McGill University, 6825 LaSalle Boulevard, Verdun, Québec, H4H 1R3, Canada
| | - Tharick A Pascoal
- Translational Neuroimaging Laboratory, The McGill University Research Centre for Studies in Aging, 6825 LaSalle Boulevard, Verdun, Québec, H4H 1R3, Canada
| | - Sulantha Mathotaarachchi
- Translational Neuroimaging Laboratory, The McGill University Research Centre for Studies in Aging, 6825 LaSalle Boulevard, Verdun, Québec, H4H 1R3, Canada
| | - Joseph Therriault
- Translational Neuroimaging Laboratory, The McGill University Research Centre for Studies in Aging, 6825 LaSalle Boulevard, Verdun, Québec, H4H 1R3, Canada
| | - Min Su Kang
- Translational Neuroimaging Laboratory, The McGill University Research Centre for Studies in Aging, 6825 LaSalle Boulevard, Verdun, Québec, H4H 1R3, Canada
| | - Monica Shin
- Translational Neuroimaging Laboratory, The McGill University Research Centre for Studies in Aging, 6825 LaSalle Boulevard, Verdun, Québec, H4H 1R3, Canada
| | - Marie-Christine Guiot
- Montreal Neurological Institute/Hospital, Department of Pathology, McGill University Hospital Centre, 3801 University Street, Montreal, Québec, H3A 2B4, Canada
| | - Qi Guo
- AbbVie Inc., 1 North Waukegan Road, North Chicago, IL, USA
| | - Ryuichi Harada
- Department of Pharmacology, Tohoku University Graduate School of Medicine, 2-1 Seiryo-machi, Aoba-ku, Sendai, 980-8575, Japan
| | | | - Gassan Massarweh
- McConnell Brain Imaging Centre, McGill University, 3801 University Street, Montreal, Québec, H3A 2B4, Canada
| | - Jean-Paul Soucy
- McConnell Brain Imaging Centre, McGill University, 3801 University Street, Montreal, Québec, H3A 2B4, Canada
| | - Nobuyuki Okamura
- Division of Pharmacology, Faculty of Medicine, Tohoku Medical and Pharmaceutical University, 4-4-1 Komatsushima, Aoba-ku, Sendai, 981-8558, Japan
| | - Serge Gauthier
- Alzheimer's Disease Research Unit, The McGill University Research Centre for Studies in Aging, McGill University, 6825 LaSalle Boulevard, Verdun, Québec, H4H 1R3, Canada
| | - Pedro Rosa-Neto
- Translational Neuroimaging Laboratory, The McGill University Research Centre for Studies in Aging, 6825 LaSalle Boulevard, Verdun, Québec, H4H 1R3, Canada. .,Alzheimer's Disease Research Unit, The McGill University Research Centre for Studies in Aging, McGill University, 6825 LaSalle Boulevard, Verdun, Québec, H4H 1R3, Canada. .,Montreal Neurological Institute, 3801 University Street, Montreal, Québec, H3A 2B4, Canada. .,Department of Neurology and Neurosurgery, McGill University, 3801 University Street, Montreal, Québec, H3A 2B4, Canada.
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14
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Sturm S, Forsberg A, Nave S, Stenkrona P, Seneca N, Varrone A, Comley RA, Fazio P, Jamois C, Nakao R, Ejduk Z, Al-Tawil N, Akenine U, Halldin C, Andreasen N, Ricci B. Positron emission tomography measurement of brain MAO-B inhibition in patients with Alzheimer's disease and elderly controls after oral administration of sembragiline. Eur J Nucl Med Mol Imaging 2017; 44:382-391. [PMID: 27633250 PMCID: PMC5281649 DOI: 10.1007/s00259-016-3510-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2016] [Accepted: 08/29/2016] [Indexed: 11/24/2022]
Abstract
PURPOSE In Alzheimer's disease (AD), increased metabolism of monoamines by monoamine oxidase type B (MAO-B) leads to the production of toxic reactive oxygen species (ROS), which are thought to contribute to disease pathogenesis. Inhibition of the MAO-B enzyme may restore brain levels of monoaminergic neurotransmitters, reduce the formation of toxic ROS and reduce neuroinflammation (reactive astrocytosis), potentially leading to neuroprotection. Sembragiline (also referred as RO4602522, RG1577 and EVT 302 in previous communications) is a potent, selective and reversible inhibitor of MAO-B developed as a potential treatment for AD. METHODS This study assessed the relationship between plasma concentration of sembragiline and brain MAO-B inhibition in patients with AD and in healthy elderly control (EC) subjects. Positron emission tomography (PET) scans using [11C]-L-deprenyl-D2 radiotracer were performed in ten patients with AD and six EC subjects, who received sembragiline each day for 6-15 days. RESULTS At steady state, the relationship between sembragiline plasma concentration and MAO-B inhibition resulted in an Emax of ∼80-90 % across brain regions of interest and in an EC50 of 1-2 ng/mL. Data in patients with AD and EC subjects showed that near-maximal inhibition of brain MAO-B was achieved with 1 mg sembragiline daily, regardless of the population, whereas lower doses resulted in lower and variable brain MAO-B inhibition. CONCLUSIONS This PET study confirmed that daily treatment of at least 1 mg sembragiline resulted in near-maximal inhibition of brain MAO-B enzyme in patients with AD.
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Affiliation(s)
- Stefan Sturm
- Roche Innovation Center Basel, Roche Pharmaceutical Research and Early Development, Grenzacherstrasse 124, Basel, Switzerland.
- F. Hoffmann-La Roche Ltd, Grenzacherstrasse 124, 4070, Basel, Switzerland.
| | - Anton Forsberg
- Department of Clinical Neuroscience, Centre for Psychiatric Research, Karolinska Institutet, Stockholm, Sweden
| | - Stephane Nave
- Roche Innovation Center Basel, Roche Pharmaceutical Research and Early Development, Grenzacherstrasse 124, Basel, Switzerland
| | - Per Stenkrona
- Department of Clinical Neuroscience, Centre for Psychiatric Research, Karolinska Institutet, Stockholm, Sweden
| | | | - Andrea Varrone
- Department of Clinical Neuroscience, Centre for Psychiatric Research, Karolinska Institutet, Stockholm, Sweden
| | | | - Patrik Fazio
- Department of Clinical Neuroscience, Centre for Psychiatric Research, Karolinska Institutet, Stockholm, Sweden
| | - Candice Jamois
- Roche Innovation Center Basel, Roche Pharmaceutical Research and Early Development, Grenzacherstrasse 124, Basel, Switzerland
| | - Ryuji Nakao
- Department of Clinical Neuroscience, Centre for Psychiatric Research, Karolinska Institutet, Stockholm, Sweden
| | - Zbigniew Ejduk
- Internal Disease and Gastroenterology, Miedzyleski Specialistic Hospital, Warsaw, Poland
| | - Nabil Al-Tawil
- Karolinska Trial Alliance Phase 1 Unit, Karolinska University Hospital, Stockholm, Sweden
| | - Ulrika Akenine
- Karolinska Institutet Alzheimer Disease Research Centre and Clinical Trial Unit, Geriatric Clinic, Karolinska University Hospital, Huddinge, Sweden
| | - Christer Halldin
- Department of Clinical Neuroscience, Centre for Psychiatric Research, Karolinska Institutet, Stockholm, Sweden
| | - Niels Andreasen
- Karolinska Institutet Alzheimer Disease Research Centre and Clinical Trial Unit, Geriatric Clinic, Karolinska University Hospital, Huddinge, Sweden
| | - Benedicte Ricci
- Roche Innovation Center Basel, Roche Pharmaceutical Research and Early Development, Grenzacherstrasse 124, Basel, Switzerland
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15
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Sawatzky E, Al-Momani E, Kobayashi R, Higuchi T, Samnick S, Decker M. A Novel Way To Radiolabel Human Butyrylcholinesterase for Positron Emission Tomography through Irreversible Transfer of the Radiolabeled Moiety. ChemMedChem 2016; 11:1540-50. [DOI: 10.1002/cmdc.201600223] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2016] [Revised: 05/30/2016] [Indexed: 11/07/2022]
Affiliation(s)
- Edgar Sawatzky
- Pharmaceutical and Medicinal Chemistry; Institute of Pharmacy and Food Chemistry; Julius Maximilian University Würzburg; Am Hubland 97074 Würzburg Germany
| | - Ehab Al-Momani
- Experimental Nuclear Medicine; Center of Inner Medicine; University Hospital Würzburg; OberdürrbacherStrasse 6 97080 Würzburg Germany
| | - Ryohei Kobayashi
- Experimental Nuclear Medicine; Center of Inner Medicine; University Hospital Würzburg; OberdürrbacherStrasse 6 97080 Würzburg Germany
| | - Takahiro Higuchi
- Experimental Nuclear Medicine; Center of Inner Medicine; University Hospital Würzburg; OberdürrbacherStrasse 6 97080 Würzburg Germany
| | - Samuel Samnick
- Experimental Nuclear Medicine; Center of Inner Medicine; University Hospital Würzburg; OberdürrbacherStrasse 6 97080 Würzburg Germany
| | - Michael Decker
- Pharmaceutical and Medicinal Chemistry; Institute of Pharmacy and Food Chemistry; Julius Maximilian University Würzburg; Am Hubland 97074 Würzburg Germany
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Rusjan PM, Wilson AA, Miler L, Fan I, Mizrahi R, Houle S, Vasdev N, Meyer JH. Kinetic modeling of the monoamine oxidase B radioligand [¹¹C]SL25.1188 in human brain with high-resolution positron emission tomography. J Cereb Blood Flow Metab 2014; 34:883-9. [PMID: 24517979 PMCID: PMC4013770 DOI: 10.1038/jcbfm.2014.34] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/30/2013] [Revised: 12/25/2013] [Accepted: 01/20/2014] [Indexed: 11/09/2022]
Abstract
This article describes the kinetic modeling of [(11)C]SL25.1188 ([(S)-5-methoxymethyl-3-[6-(4,4,4-trifluorobutoxy)-benzo[d]isoxazol-3-yl]-oxazolidin-2-[(11)C]one]) binding to monoamine oxidase B (MAO-B) in the human brain using high-resolution positron emission tomography (PET). Seven healthy subjects underwent two separate 90- minute PET scans after an intravenous injection of [(11)C]SL25.1188. Complementary arterial blood sampling was acquired. Radioactivity was quickly eliminated from plasma with 80% of parent compound remaining at 90 minutes. Metabolites were more polar than the parent compound. Time-activity curves showed high brain uptake, early peak and washout rate consistent with known regional MAO-B concentration. A two-tissue compartment model (2-TCM) provided better fits to the data than a 1-TCM. Measurement of total distribution volume (VT) showed very good identifiability (based on coefficient of variation (COV)) for all regions of interest (ROIs) (COV(VT)<8%), low between-subject variability (∼20%), and quick temporal convergence (within 5% of final value at 45 minutes). Logan graphical method produces very good estimation of VT. Regional VT highly correlated with previous postmortem report of MAO-B level (r(2)= ≥ 0.9). Specific binding would account from 70% to 90% of VT. Hence, VT measurement of [(11)C]SL25.1(1)88 PET is an excellent estimation of MAO-B concentration.
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Affiliation(s)
- Pablo M Rusjan
- Research Imaging Centre, Centre for Addiction and Mental Health (CAMH), Toronto, Ontario, Canada
| | - Alan A Wilson
- 1] Research Imaging Centre, Centre for Addiction and Mental Health (CAMH), Toronto, Ontario, Canada [2] Department of Psychiatry, University of Toronto, Toronto, Ontario, Canada
| | - Laura Miler
- Research Imaging Centre, Centre for Addiction and Mental Health (CAMH), Toronto, Ontario, Canada
| | - Ian Fan
- Research Imaging Centre, Centre for Addiction and Mental Health (CAMH), Toronto, Ontario, Canada
| | - Romina Mizrahi
- 1] Research Imaging Centre, Centre for Addiction and Mental Health (CAMH), Toronto, Ontario, Canada [2] Department of Psychiatry, University of Toronto, Toronto, Ontario, Canada
| | - Sylvain Houle
- 1] Research Imaging Centre, Centre for Addiction and Mental Health (CAMH), Toronto, Ontario, Canada [2] Department of Psychiatry, University of Toronto, Toronto, Ontario, Canada
| | - Neil Vasdev
- Division of Nuclear Medicine and Molecular Imaging, Massachusetts General Hospital, and Department of Radiology, Harvard Medical School, Boston, Massachusetts, USA
| | - Jeffrey H Meyer
- 1] Research Imaging Centre, Centre for Addiction and Mental Health (CAMH), Toronto, Ontario, Canada [2] Department of Psychiatry, University of Toronto, Toronto, Ontario, Canada
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17
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Modeling of PET data in CNS drug discovery and development. J Pharmacokinet Pharmacodyn 2013; 40:267-79. [PMID: 23660778 DOI: 10.1007/s10928-013-9320-6] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2013] [Accepted: 04/26/2013] [Indexed: 12/22/2022]
Abstract
Positron emission tomography (PET) is increasingly used in drug discovery and development for evaluation of CNS drug disposition and for studies of disease biomarkers to monitor drug effects on brain pathology. The quantitative analysis of PET data is based on kinetic modeling of radioactivity concentrations in plasma and brain tissue compartments. A number of quantitative methods of analysis have been developed that allow the determination of parameters describing drug pharmacokinetics and interaction with target binding sites in the brain. The optimal method of quantification depends on the properties of the radiolabeled drug or radioligand and the binding site studied. We here review the most frequently used methods for quantification of PET data in relation to CNS drug discovery and development. The utility of PET kinetic modeling in the development of novel CNS drugs is illustrated by examples from studies of the brain kinetic properties of radiolabeled drug molecules.
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Patel NH, Vyas NS, Puri BK, Nijran KS, Al-Nahhas A. Positron emission tomography in schizophrenia: a new perspective. J Nucl Med 2010; 51:511-20. [PMID: 20237027 DOI: 10.2967/jnumed.109.066076] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
UNLABELLED PET is an important functional imaging technique that can be used to investigate neurotransmitter receptors and transporters directly by mapping human brain function. PET is increasingly being used greatly to advance our understanding of the neurobiology and pathophysiology of schizophrenia. METHODS This review focuses on the use of PET tracers and kinetic modeling in identifying regional brain abnormalities and regions associated with cognitive functioning in schizophrenia. A variety of PET tracers have been used to identify brain abnormalities, including (11)C, (15)O-water, (18)F-fallypride, and L-3,4-dihydroxy-6-(18)F-fluorophenylalanine ((18)F-FDOPA). RESULTS Some studies have used compartmental modeling to determine tracer binding kinetics. The most consistent findings show a difference in the dopamine content in the prefrontal cortex, anterior cingulate gyrus, and hippocampus between healthy controls and patients with schizophrenia. Studies also show a higher density of D(2) receptors in the striatum and neural brain dysconnectivity. CONCLUSION Future investigations integrating clinical, imaging, genetic, and cognitive aspects are warranted to gain a better understanding of the pathophysiology of this disorder.
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Affiliation(s)
- Neva H Patel
- Radiological Sciences Unit, Imperial College Healthcare NHS Trust, London, United Kingdom.
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19
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Saba W, Valette H, Peyronneau MA, Bramoullé Y, Coulon C, Curet O, George P, Dollé F, Bottlaender M. [11C]SL25.1188, a new reversible radioligand to study the monoamine oxidase type B with PET: Preclinical characterisation in nonhuman primate. Synapse 2010; 64:61-9. [DOI: 10.1002/syn.20703] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Hirvonen J, Kailajärvi M, Haltia T, Koskimies S, Någren K, Virsu P, Oikonen V, Sipilä H, Ruokoniemi P, Virtanen K, Scheinin M, Rinne JO. Assessment of MAO-B occupancy in the brain with PET and [11C]-L-deprenyl-D2: a dose-finding study with a novel MAO-B inhibitor, EVT 301. Clin Pharmacol Ther 2009; 85:506-12. [PMID: 19129751 DOI: 10.1038/clpt.2008.241] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Inhibition of monoamine oxidase type B (MAO-B) activity in the brain is a putative strategy for the treatment of Alzheimer's disease (AD). We performed a dose-selection and validation study of a novel, reversible MAO-B inhibitor, EVT 301. Sixteen healthy volunteers received selegiline (10 mg) or EVT 301 (25, 75, or 150 mg) daily for 7-8 days, and four subjects with AD received 75 mg of EVT 301. MAO-B occupancy in the brain was assessed using positron emission tomography (PET) with [11C]-L-deprenyl-D2. EVT 301 was found to dose-dependently occupy MAO-B in the human brain, with occupancy ranging from 58-78% at a dose of 25 mg to 73-90% at a dose of 150 mg. The corresponding occupancy after selegiline was 77-92%. Determination of MAO-B inhibition in blood platelets underestimated the actual brain occupancy achieved with EVT 301. A daily EVT 301 dose of 75 or 150 mg appears suitable for clinical efficacy studies in patients with AD.
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Affiliation(s)
- J Hirvonen
- Turku PET Centre, University of Turku and Turku University Central Hospital, Turku, Finland
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Szabo Z, Xia J, Mathews WB. Radiopharmaceuticals for renal positron emission tomography imaging. Semin Nucl Med 2008; 38:20-31. [PMID: 18096461 DOI: 10.1053/j.semnuclmed.2007.09.008] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Radiopharmaceuticals for functional renal imaging, including renal blood flow, renal blood volume, glomerular excretion, and metabolism have been available for some time. This review outlines radiopharmaceuticals for functional renal imaging as well as those that target pertinent molecular constituents of renal injury and repair. The angiotensin and endothelin receptors are particularly appealing molecular targets for renal imaging because of their association with renal physiology and pathology. Other targets such as the vascular endothelial growth factor (VEGF) receptor, integrin, or phosphatidylserine have been investigated at length for cancer imaging, but they are just as important constituents of the renal injury/repair process. Various diseases can involve identical mechanisms, such as angiogenesis and apoptosis, and radiopharmaceuticals developed for these processes in other organs can also be used for renal imaging. The sensitivity and spatial resolution of positron emission tomography makes it an ideal tool for molecular and functional kidney imaging. Radiopharmaceutical development for the kidneys must focus on achieving high target selectivity and binding affinity, stability and slow metabolism in vivo, and minimal nonspecific accumulation and urinary excretion.
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Affiliation(s)
- Zsolt Szabo
- Department of Radiology and Radiological Sciences, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.
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Bramoullé Y, Puech F, Saba W, Valette H, Bottlaender M, George P, Dollé F. Radiosynthesis of (S)-5-methoxymethyl-3-[6-(4,4,4-trifluorobutoxy)benzo[d]isoxazol-3-yl] oxazolidin-2-[11C]one ([11C]SL25.1188), a novel radioligand for imaging monoamine oxidase-B with PET. J Labelled Comp Radiopharm 2008. [DOI: 10.1002/jlcr.1492] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Abourbeh G, Dissoki S, Jacobson O, Litchi A, Ben Daniel R, Laki D, Levitzki A, Mishani E. Evaluation of radiolabeled ML04, a putative irreversible inhibitor of epidermal growth factor receptor, as a bioprobe for PET imaging of EGFR-overexpressing tumors. Nucl Med Biol 2007; 34:55-70. [PMID: 17210462 DOI: 10.1016/j.nucmedbio.2006.10.012] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2006] [Accepted: 10/28/2006] [Indexed: 12/21/2022]
Abstract
Overexpression of epidermal growth factor receptor (EGFR) has been implicated in tumor development and malignancy. Evaluating the degree of EGFR expression in tumors could aid in identifying patients for EGFR-targeted therapies and in monitoring treatment. Nevertheless, no currently available assay can reliably quantify receptor content in tumors. Radiolabeled inhibitors of EGFR-TK could be developed as bioprobes for positron emission tomography imaging. Such imaging agents would not only provide a noninvasive quantitative measurement of EGFR content in tumors but also serve as radionuclide carriers for targeted radiotherapy. The potency, reversibility, selectivity and specific binding characteristics of ML04, an alleged irreversible inhibitor of EGFR, were established in vitro. The distribution of the F-18-labeled compound and the extent of EGFR-specific tumor uptake were evaluated in tumor-bearing mice. ML04 demonstrated potent, irreversible and selective inhibition of EGFR, combined with specific binding to the receptor in intact cells. In vivo distribution of the radiolabeled compound revealed tumor/blood and tumor/muscle activity uptake ratios of about 7 and 5, respectively, 3 h following administration of a radiotracer. Nevertheless, only minor EGFR-specific uptake of the compound was detected in these studies, using either EGFR-negative tumors or blocking studies as controls. To improve the in vivo performance of ML04, administration via prolonged intravenous infusion is proposed. Detailed pharmacokinetic characterization of this bioprobe could assist in the development of a kinetic model that would afford accurate measurement of EGFR content in tumors.
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Affiliation(s)
- Galith Abourbeh
- Department of Medical Biophysics and Nuclear Medicine, Hadassah Hebrew University, Jerusalem 91120, Israel
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24
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Johansson A, Engler H, Blomquist G, Scott B, Wall A, Aquilonius SM, Långström B, Askmark H. Evidence for astrocytosis in ALS demonstrated by [11C](L)-deprenyl-D2 PET. J Neurol Sci 2007; 255:17-22. [PMID: 17346749 DOI: 10.1016/j.jns.2007.01.057] [Citation(s) in RCA: 103] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2006] [Revised: 01/19/2007] [Accepted: 01/23/2007] [Indexed: 12/11/2022]
Abstract
OBJECTIVE To use deuterium-substituted [11C](L)-deprenyl PET to depict astrocytosis in vivo in patients with amyotrophic lateral sclerosis (ALS). BACKGROUND In human brain, the enzyme MAO-B is primarily located in astrocytes. L-deprenyl binds to MAO-B and autoradiography with 3H-L-deprenyl has been used to map astrocytosis in vitro. Motor neuron loss in ALS is accompanied by astrocytosis and astrocytes may play an active role in the neurodegenerative process. Deuterium-substituted [11C](L)-deprenyl PET provides an opportunity to localize astrocytosis in vivo in the brain of patients with ALS. METHODS Deuterium-substituted [11C](L)-deprenyl PET was performed in seven patients with ALS and seven healthy control subjects. RESULTS Increased uptake rate of [11C](L)-deprenyl was demonstrated in ALS in pons and white matter. CONCLUSION This study provides evidence that astrocytosis may be detected in vivo in ALS by the use of deuterium-substituted [11C](L)-deprenyl PET though further studies are needed to determine whether deuterium-substituted [11C](L)-deprenyl binding tracks disease progression and reflects astrocytosis.
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Affiliation(s)
- Anders Johansson
- Department of Neurology, University Hospital, S-751 85 Uppsala, Sweden.
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25
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Razifar P, Axelsson J, Schneider H, Långström B, Bengtsson E, Bergström M. A new application of pre-normalized principal component analysis for improvement of image quality and clinical diagnosis in human brain PET studies—Clinical brain studies using [11C]-GR205171, [11C]-l-deuterium-deprenyl, [11C]-5-Hydroxy-l-Tryptophan, [11C]-l-DOPA and Pittsburgh Compound-B. Neuroimage 2006; 33:588-98. [PMID: 16934493 DOI: 10.1016/j.neuroimage.2006.05.060] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2005] [Revised: 05/11/2006] [Accepted: 05/23/2006] [Indexed: 10/24/2022] Open
Abstract
Principal component analysis (PCA) is one of the most applied multivariate image analysis tool on dynamic Positron Emission Tomography (PET). Independent of used reconstruction methodologies, PET images contain correlation in-between pixels, correlations in-between frame and errors caused by the reconstruction algorithm including different corrections, which can affect the performance of the PCA. In this study, we have investigated a new approach of application of PCA on pre-normalized, dynamic human PET images. A range of different tracers have been used for this purpose to explore the performance of the new method as a way to improve detection and visualization of significant changes in tracer kinetics and to enhance the discrimination between pathological and healthy regions in the brain. We compare the new results with the results obtained using other methods. Images generated using the new approach contain more detailed anatomical information with higher quality, precision and visualization, compared with images generated using other methods.
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Affiliation(s)
- Pasha Razifar
- Uppsala University, Centre for Image Analysis, Lägerhyddsv. 3, SE-752 37 Uppsala, Sweden
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26
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Theuns J, Marjaux E, Vandenbulcke M, Van Laere K, Kumar-Singh S, Bormans G, Brouwers N, Van den Broeck M, Vennekens K, Corsmit E, Cruts M, De Strooper B, Van Broeckhoven C, Vandenberghe R. Alzheimer dementia caused by a novel mutation located in the APP C-terminal intracytosolic fragment. Hum Mutat 2006; 27:888-96. [PMID: 16917905 DOI: 10.1002/humu.20402] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Since the first report showing that Alzheimer disease (AD) might be caused by mutations in the amyloid precursor protein gene (APP), 20 different missense mutations have been reported. The majority of early-onset AD mutations alter processing of APP increasing relative levels of Abeta42 peptide, either by increasing Abeta42 or decreasing Abeta40 peptide levels or both. In a diagnostic setting using direct sequence analysis, we identified in one patient with familial early-onset AD a novel mutation in APP (c.2172G>C), predicting a K724N substitution in the intracytosolic fragment. The mutation is located downstream of the epsilon-cleavage site of APP and is the furthermost C-terminal mutation reported to date. In vitro expression of APP K724N cDNA showed an increase in Abeta42 and a decrease in Abeta40 levels resulting in a near three-fold increase of the Abeta42/Abeta40 ratio. Further, in vivo amyloid positron emission tomography (PET) imaging revealed significantly increased cortical amyloid deposits, supporting that in human this novel APP mutation is likely causing disease.
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Affiliation(s)
- J Theuns
- Neurodegenerative Brain Diseases Group, Department of Molecular Genetics, Flanders Interuniversity Institute for Biotechnology, Belgium
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Fowler JS, Logan J, Volkow ND, Wang GJ. Translational neuroimaging: positron emission tomography studies of monoamine oxidase. Mol Imaging Biol 2006; 7:377-87. [PMID: 16265597 DOI: 10.1007/s11307-005-0016-1] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Positron emission tomography (PET) using radiotracers with high molecular specificity is an important scientific tool in studies of monoamine oxidase (MAO), an important enzyme in the regulation of the neurotransmitters dopamine, norepinephrine, and serotonin as well as the dietary amine, tyramine. MAO occurs in two different subtypes, MAO A and MAO B, which have different substrate and inhibitor specificity and which are different gene products. The highly variable subtype distribution with different species makes human studies of special value. MAO A and B can be imaged in the human brain and certain peripheral organs using PET and carbon-11 (half-life 20.4 minutes) labeled mechanism-based irreversible inhibitors, clorgyline and L -deprenyl, respectively. In this article we introduce MAO and describe the development of these radiotracers and their translation from preclinical studies to the investigation of variables affecting MAO in the human brain and peripheral organs.
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Jensen SB, Olsen AK, Pedersen K, Cumming P. Effect of monoamine oxidase inhibition on amphetamine-evoked changes in dopamine receptor availability in the living pig: A dual tracer PET study with [11C]harmine and [11C]raclopride. Synapse 2006; 59:427-34. [PMID: 16485265 DOI: 10.1002/syn.20258] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The activity of both isozymes of monoamine oxidase (MAO) is reduced by 50% in the brain of human smokers. We hypothesized that this is not an epiphenomenon, but should bring about potentiation of the action of psychostimulant drugs. To test this hypothesis, we carried out serial positron emission tomography (PET) studies in Göttingen miniature pigs to measure the binding of the MAO-A ligand [11C]harmine and to measure the changes in [11C]raclopride binding evoked by a low dose of amphetamine (0.7 mg/kg as free base, i.v.), first in a baseline condition, and, one month later, after acute treatment with pargyline (2 x 3 mg/kg as free base, i.m.). In the baseline, the distribution volume of [11C]harmine relative to the arterial input (V(d), ml g(-1)) ranged from 74 ml g(-1) in cerebellum to 139 ml g(-1) in the medial hypothalamus. Pargyline treatment reduced the magnitude of V(d) globally to 34-54 ml g(-1). Nearly complete displacement of [11C]harmine binding was detected in neocortex and striatum, but there was evidence for pargyline-resistant binding in the pituitary gland and diencephalon. In the baseline condition, the low dose of amphetamine evoked a 14% decline in the binding potential (BP) (pB) of [11C]raclopride in striatum (P = 0.026). After pargyline treatment, the amphetamine effect was of similar magnitude (-11%), although not statistically significant (P = 0.054). However, the second amphetamine challenge evoked a 24% reduction in [11C]raclopride pB relative to the original baseline condition (P = 0.018). Present results do not strongly support our hypothesis that MAO inhibition should potentiate the amphetamine-evoked dopamine release as measured in the [11C]raclopride competition paradigm.
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Affiliation(s)
- Svend Borup Jensen
- PET Centre, Aarhus University Hospital, Nørrebrogade 44, Aarhus C, Denmark 8000
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29
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Frankle WG, Slifstein M, Talbot PS, Laruelle M. Neuroreceptor Imaging in Psychiatry: Theory and Applications. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2005; 67:385-440. [PMID: 16291028 DOI: 10.1016/s0074-7742(05)67011-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- W Gordon Frankle
- Departments of Psychiatry, Columbia University College of Physicians and Surgeons and New York State Psychiatric Institute, New York, New York 10032, USA
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30
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Fowler JS, Logan J, Wang GJ, Volkow ND, Telang F, Ding YS, Shea C, Garza V, Xu Y, Li Z, Alexoff D, Vaska P, Ferrieri R, Schlyer D, Zhu W, John Gatley S. Comparison of the binding of the irreversible monoamine oxidase tracers, [(11)C]clorgyline and [(11)C]l-deprenyl in brain and peripheral organs in humans. Nucl Med Biol 2004; 31:313-9. [PMID: 15028243 DOI: 10.1016/j.nucmedbio.2003.10.003] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2003] [Accepted: 10/03/2003] [Indexed: 12/13/2022]
Abstract
The monoamine oxidase A and B (MAO A and B) radiotracers [(11)C]clorgyline (CLG) and [(11)C]L-deprenyl (DEP) and their deuterium labeled counterparts (CLG-D and DEP-D) were compared to determine whether their distribution and kinetics in humans are consistent with their physical, chemical and pharmacological properties and the reported ratios of MAO A:MAO B in post-mortem human tissues. Irreversible binding was consistently higher for DEP in brain, heart, kidneys and spleen but not lung where CLG >DEP and not in thyroid where there is no DEP binding. The generally higher DEP binding is consistent with its higher enzyme affinity and larger free fraction in plasma while differences in regional distribution for CLG and DEP in brain, heart, thyroid and lungs are consistent with different relative ratios of MAO A and B in humans.
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Affiliation(s)
- Joanna S Fowler
- Brookhaven National Laboratory, Chemistry Department, Bldg 555, Upton, NY 11973, USA.
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31
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Fowler JS, Logan J, Wang GJ, Franceschi D, Volkow ND, Telang F, Pappas N, Ferrieri R, Shea C, Garza V, Xu Y, King P, Schlyer D, Gatley SJ, Ding YS, Warner D, Netusil N, Carter P, Jayne M, Alexoff D, Zhu W, Vaska P. Monoamine oxidase A imaging in peripheral organs in healthy human subjects. Synapse 2003; 49:178-87. [PMID: 12774302 DOI: 10.1002/syn.10231] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Monoamine oxidase (MAO) catalyzes the oxidative deamination of many biogenic and dietary amines. Though studies of MAO have focused mainly on its regulatory role in the brain, MAO in peripheral organs also represents a vast mechanism for detoxifying vasoactive compounds as well as for terminating the action of physiologically active amines, which can cross the blood brain barrier. Indeed, robust central and peripheral MAO activity is a major requirement in the safe use of many CNS drugs, particularly antidepressants, and thus an awareness of the MAO inhibitory potential of drugs is essential in therapeutics. In this study, we examined the feasibility of quantifying MAO A in peripheral organs in healthy human subjects using comparative positron emission tomography (PET) imaging with carbon-11 (t(1/2): 20.4 min) labeled clorgyline ([(11)C]clorgyline) a suicide inactivator of MAO A and its deuterium labeled counterpart ([(11)C]clorgyline-D2). Heart, lungs, kidneys, thyroid, and spleen showed a robust deuterium isotope effect characteristic of MAO and the magnitude of the effect was similar to that of trancylcypromine, an irreversible MAO inhibitor used in the treatment of depression. Liver time-activity curves were not affected by deuterium substitution precluding the estimation of liver MAO in vivo. In organs showing an isotope effect, MAO A is greatest in the lungs and kidneys followed by the thyroid and heart. This method, which has been previously applied in the human brain, opens the possibility to also directly assess the effects of different variables including smoking, dietary substances, drugs, disease, and genetics on peripheral MAO A in humans.
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Affiliation(s)
- Joanna S Fowler
- Chemistry Department, Brookhaven National Laboratory, Upton, New York 11973, USA.
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32
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Fowler JS, Logan J, Ding YS, Franceschi D, Wang GJ, Volkow ND, Pappas N, Schlyer D, Gatley SJ, Alexoff D, Felder C, Biegon A, Zhu W. Non-MAO A binding of clorgyline in white matter in human brain. J Neurochem 2001; 79:1039-46. [PMID: 11739617 DOI: 10.1046/j.1471-4159.2001.00649.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Clorgyline is an irreversible inhibitor of monoamine oxidase (MAO A) which has been labeled with carbon-11 (C-11) and used to measure human brain MAO A with positron emission tomography (PET). In this study we compared [11C]clorgyline and deuterium-substituted [11C]clorgyline ([11C]clorgyline-D2) to better understand the molecular link between [11C]clorgyline binding and MAO A. In PET studies of five normal healthy volunteers scanned with [11C]clorgyline and [11C]clorgyline-D2 2 h apart, deuterium substitution generally produced the expected reductions in the brain uptake of [11C]clorgyline. However, the reduction was not uniform with the C-11 binding in white matter being significantly less sensitive to deuterium substitution than other brain regions. The percentages of the total binding attributable to MAO A is largest for the thalamus and smallest for the white matter and this is clearly seen in PET images with [11C]clorgyline-D2. Thus deuterium-substituted [11C]clorgyline selectively reduces the MAO A binding component of clorgyline in the human brain revealing non-MAO A binding which is most apparent in the white matter. The characterization of the non-MAO A binding component of this widely used MAO A inhibitor merits further investigation.
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Affiliation(s)
- J S Fowler
- Chemistry Department, Brookhaven National Laboratory, Upton, New York 11973, USA.
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Abstract
The differential equations of compartmental analysis form the basis of the models describing the uptake of tracers used in imaging studies. Graphical analyses convert the model equations into linear plots, the slopes of which represent measures of tracer binding. The graphical methods are not dependent upon a particular model structure but the slopes can be related to combinations of the model parameters if a model structure is assumed. The input required is uptake data from a region of interest vs time and an input function that can either be plasma measurements or uptake data from a suitable reference region. Graphical methods can be applied to both reversible and irreversibly binding tracers. They provide considerable ease of computation compared to the optimization of individual model parameters in the solution of the differential equations generally used to describe the binding of tracers. Conditions under which the graphical techniques are applicable and some problems encountered in separating tracer delivery and binding are considered. Also the effect of noise can introduce a bias in the distribution volume which is the slope of the graphical analysis of reversible tracers. Smoothing techniques may minimize this problem and retain the model independence. In any case graphical techniques can provide insight into the binding kinetics of tracers in a visual way.
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Affiliation(s)
- J Logan
- Chemistry Department, Brookhaven National Laboratory, Upton, New York 11973, USA.
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