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Kong Y, Maschio CA, Shi X, Xie F, Zuo C, Konietzko U, Shi K, Rominger A, Xiao J, Huang Q, Nitsch RM, Guan Y, Ni R. Relationship Between Reactive Astrocytes, by [ 18F]SMBT-1 Imaging, with Amyloid-Beta, Tau, Glucose Metabolism, and TSPO in Mouse Models of Alzheimer's Disease. Mol Neurobiol 2024; 61:8387-8401. [PMID: 38502413 DOI: 10.1007/s12035-024-04106-7] [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: 09/25/2023] [Accepted: 03/06/2024] [Indexed: 03/21/2024]
Abstract
Reactive astrocytes play an important role in the development of Alzheimer's disease (AD). Here, we aimed to investigate the temporospatial relationships among monoamine oxidase-B, tau and amyloid-β (Aβ), translocator protein, and glucose metabolism by using multitracer imaging in AD transgenic mouse models. Positron emission tomography (PET) imaging with [18F]SMBT-1 (monoamine oxidase-B), [18F]florbetapir (Aβ), [18F]PM-PBB3 (tau), [18F]fluorodeoxyglucose (FDG), and [18F]DPA-714 (translocator protein) was carried out in 5- and 10-month-old APP/PS1, 11-month-old 3×Tg mice, and aged-matched wild-type mice. The brain regional referenced standard uptake value (SUVR) was computed with the cerebellum as the reference region. Immunofluorescence staining was performed on mouse brain tissue slices. [18F]SMBT-1 and [18F]florbetapir SUVRs were greater in the cortex and hippocampus of 10-month-old APP/PS1 mice than in those of 5-month-old APP/PS1 mice and wild-type mice. No significant difference in the regional [18F]FDG or [18F]DPA-714 SUVRs was observed in the brains of 5- or 10-month-old APP/PS1 mice or wild-type mice. No significant difference in the SUVRs of any tracer was observed between 11-month-old 3×Tg mice and age-matched wild-type mice. A positive correlation between the SUVRs of [18F]florbetapir and [18F]DPA-714 in the cortex and hippocampus was observed among the transgenic mice. Immunostaining validated the distribution of MAO-B and limited Aβ and tau pathology in 11-month-old 3×Tg mice; and Aβ deposits in brain tissue from 10-month-old APP/PS1 mice. In summary, these findings provide in vivo evidence that an increase in astrocyte [18F]SMBT-1 accompanies Aβ accumulation in APP/PS1 models of AD amyloidosis.
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Affiliation(s)
- Yanyan Kong
- PET Center, Huashan Hospital, Fudan University, Shanghai, China
| | - Cinzia A Maschio
- Institute for Regenerative Medicine, University of Zurich, Zurich, Switzerland
- Zurich Neuroscience Zentrum (ZNZ), Zurich, Switzerland
| | - Xuefeng Shi
- Qinghai Provincial People's Hospital, Xining, China
| | - Fang Xie
- PET Center, Huashan Hospital, Fudan University, Shanghai, China
| | - Chuantao Zuo
- PET Center, Huashan Hospital, Fudan University, Shanghai, China
| | - Uwe Konietzko
- Institute for Regenerative Medicine, University of Zurich, Zurich, Switzerland
| | - Kuangyu Shi
- Department of Nuclear Medicine, Inselspital, University of Bern, Bern, Switzerland
| | - Axel Rominger
- Department of Nuclear Medicine, Inselspital, University of Bern, Bern, Switzerland
| | - Jianfei Xiao
- PET Center, Huashan Hospital, Fudan University, Shanghai, China
| | - Qi Huang
- PET Center, Huashan Hospital, Fudan University, Shanghai, China
| | - Roger M Nitsch
- Institute for Regenerative Medicine, University of Zurich, Zurich, Switzerland
| | - Yihui Guan
- PET Center, Huashan Hospital, Fudan University, Shanghai, China.
| | - Ruiqing Ni
- Institute for Regenerative Medicine, University of Zurich, Zurich, Switzerland.
- Zurich Neuroscience Zentrum (ZNZ), Zurich, Switzerland.
- Department of Nuclear Medicine, Inselspital, University of Bern, Bern, Switzerland.
- Institute for Biomedical Engineering, University of Zurich & ETH Zurich, Zurich, Switzerland.
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Kong Y, Cao L, Wang J, Zhuang J, Xie F, Zuo C, Huang Q, Shi K, Rominger A, Li M, Wu P, Guan Y, Ni R. In vivo reactive astrocyte imaging using [ 18F]SMBT-1 in tauopathy and familial Alzheimer's disease mouse models: A multi-tracer study. J Neurol Sci 2024; 462:123079. [PMID: 38878650 DOI: 10.1016/j.jns.2024.123079] [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: 01/24/2024] [Revised: 05/13/2024] [Accepted: 06/03/2024] [Indexed: 07/12/2024]
Abstract
BACKGROUND Reactive astrocytes play an important role in the development of Alzheimer's disease and primary tauopathies. Here, we aimed to investigate the relationships between reactive astrocytes. Microgliosis and glucose metabolism with Tau and amyloid beta pathology by using multi-tracer imaging in widely used tauopathy and familial Alzheimer's disease mouse models. RESULTS Positron emission tomography imaging using [18F]PM-PBB3 (tau), [18F]florbetapir (amyloid-beta), [18F]SMBT-1 (monoamine oxidase-B), [18F]DPA-714 (translocator protein) and [18F]fluorodeoxyglucose was carried out in 3- and 7-month-old rTg4510 tau mice, 5 × FAD familial Alzheimer's disease mice and wild-type mice. Immunofluorescence staining was performed to validate the pathological distribution in the mouse brain after in vivo imaging. We found increased regional levels of [18F]PM-PBB3, [18F]SMBT-1, and [18F]DPA-714 and hypoglucose metabolism in the brains of 7-month-old rTg4510 mice compared to age-matched wild-type mice. Increased [18F]SMBT-1 uptake was observed in the brains of 3, 7-month-old 5 × FAD mice, with elevated regional [18F]florbetapir and [18F]DPA-714 uptakes in the brains of 7-month-old 5 × FAD mice, compared to age-matched wild-type mice. Positive correlations were shown between [18F]SMBT-1 and [18F]PM-PBB3, [18F]DPA-714 and [18F]PM-PBB3 in rTg4510 mice, and between [18F]florbetapir and [18F]DPA-714 SUVRs in 5 × FAD mice. CONCLUSION In summary, these findings provide in vivo evidence that reactive astrocytes, microglial activation, and cerebral hypoglucose metabolism are associated with tau and amyloid pathology development in animal models of tauopathy and familial Alzheimer's disease.
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Affiliation(s)
- Yanyan Kong
- PET Center, Huashan Hospital, Fudan University, Shanghai, China
| | - Lei Cao
- PET Center, Huashan Hospital, Fudan University, Shanghai, China; Inst. Regenerative Medicine, University of Zurich, Zurich, Switzerland
| | - Jiao Wang
- Lab of Molecular Neural Biology, School of Life Sciences, Shanghai University, Shanghai, China
| | - Junyi Zhuang
- Lab of Molecular Neural Biology, School of Life Sciences, Shanghai University, Shanghai, China
| | - Fang Xie
- PET Center, Huashan Hospital, Fudan University, Shanghai, China
| | - Chuantao Zuo
- PET Center, Huashan Hospital, Fudan University, Shanghai, China
| | - Qi Huang
- PET Center, Huashan Hospital, Fudan University, Shanghai, China
| | - Kuangyu Shi
- Dept. Nuclear Medicine, Bern University Hospital, Bern, Switzerland
| | - Axel Rominger
- Dept. Nuclear Medicine, Bern University Hospital, Bern, Switzerland
| | - Ming Li
- PET Center, Huashan Hospital, Fudan University, Shanghai, China
| | - Ping Wu
- PET Center, Huashan Hospital, Fudan University, Shanghai, China
| | - Yihui Guan
- PET Center, Huashan Hospital, Fudan University, Shanghai, China.
| | - Ruiqing Ni
- Inst. Regenerative Medicine, University of Zurich, Zurich, Switzerland; Dept. Nuclear Medicine, Bern University Hospital, Bern, Switzerland; Inst. Biomedical Engineering, ETH Zurich, Zurich, Switzerland.
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Kong Y, Cao L, Xie F, Wang X, Zuo C, Shi K, Rominger A, Huang Q, Xiao J, Jiang D, Guan Y, Ni R. Reduced SV2A and GABA A receptor levels in the brains of type 2 diabetic rats revealed by [ 18F]SDM-8 and [ 18F]flumazenil PET. Biomed Pharmacother 2024; 172:116252. [PMID: 38325265 DOI: 10.1016/j.biopha.2024.116252] [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: 09/11/2023] [Revised: 12/19/2023] [Accepted: 02/02/2024] [Indexed: 02/09/2024] Open
Abstract
PURPOSE Type 2 diabetes mellitus (T2DM) is associated with a greater risk of Alzheimer's disease. Synaptic impairment and protein aggregates have been reported in the brains of T2DM models. Here, we assessed whether neurodegenerative changes in synaptic vesicle 2 A (SV2A), γ-aminobutyric acid type A (GABAA) receptor, amyloid-β, tau and receptor for advanced glycosylation end product (RAGE) can be detected in vivo in T2DM rats. METHODS Positron emission tomography (PET) using [18F]SDM-8 (SV2A), [18F]flumazenil (GABAA receptor), [18F]florbetapir (amyloid-β), [18F]PM-PBB3 (tau), and [18F]FPS-ZM1 (RAGE) was carried out in 12-month-old diabetic Zucker diabetic fatty (ZDF) and SpragueDawley (SD) rats. Immunofluorescence staining, Thioflavin S staining, proteomic profiling and pathway analysis were performed on the brain tissues of ZDF and SD rats. RESULTS Reduced cortical [18F]SDM-8 uptake and cortical and hippocampal [18F]flumazenil uptake were observed in 12-month-old ZDF rats compared to SD rats. The regional uptake of [18F]florbetapir and [18F]PM-PBB3 was comparable in the brains of 12-month-old ZDF and SD rats. Immunofluorescence staining revealed Thioflavin S-negative, phospho-tau-positive inclusions in the cortex and hypothalamus in the brains of ZDF rats and the absence of amyloid-beta deposits. The level of GABAA receptors was lower in the cortex of ZDF rats than SD rats. Proteomic analysis further demonstrated that, compared with SD rats, synaptic-related proteins and pathways were downregulated in the hippocampus of ZDF rats. CONCLUSION These findings provide in vivo evidence for regional reductions in SV2A and GABAA receptor levels in the brains of aged T2DM ZDF rats.
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Affiliation(s)
- Yanyan Kong
- PET Center, Huashan Hospital, Fudan University, Shanghai, China
| | - Lei Cao
- PET Center, Huashan Hospital, Fudan University, Shanghai, China; Inst. Regenerative Medicine, University of Zurich, Zurich, Switzerland
| | - Fang Xie
- PET Center, Huashan Hospital, Fudan University, Shanghai, China
| | - Xiuzhe Wang
- Dept. Neurology, Shanghai Sixth People's Hospital affiliated with Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Chuantao Zuo
- PET Center, Huashan Hospital, Fudan University, Shanghai, China
| | - Kuangyu Shi
- Dept. Nuclear Medicine, Inselspital, Bern University Hospital, Bern, Switzerland
| | - Axel Rominger
- Dept. Nuclear Medicine, Inselspital, Bern University Hospital, Bern, Switzerland
| | - Qi Huang
- PET Center, Huashan Hospital, Fudan University, Shanghai, China
| | - Jianfei Xiao
- PET Center, Huashan Hospital, Fudan University, Shanghai, China
| | - Donglang Jiang
- PET Center, Huashan Hospital, Fudan University, Shanghai, China
| | - Yihui Guan
- PET Center, Huashan Hospital, Fudan University, Shanghai, China.
| | - Ruiqing Ni
- Inst. Regenerative Medicine, University of Zurich, Zurich, Switzerland; Dept. Nuclear Medicine, Inselspital, Bern University Hospital, Bern, Switzerland; Inst. Biomedical Engineering, University of Zurich & ETH Zurich, Zurich, Switzerland.
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Kubota M, Endo H, Takahata K, Tagai K, Suzuki H, Onaya M, Sano Y, Yamamoto Y, Kurose S, Matsuoka K, Seki C, Shinotoh H, Kawamura K, Zhang MR, Takado Y, Shimada H, Higuchi M. In vivo PET classification of tau pathologies in patients with frontotemporal dementia. Brain Commun 2024; 6:fcae075. [PMID: 38510212 PMCID: PMC10953627 DOI: 10.1093/braincomms/fcae075] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2023] [Revised: 12/23/2023] [Accepted: 02/29/2024] [Indexed: 03/22/2024] Open
Abstract
Frontotemporal dementia refers to a group of neurodegenerative disorders with diverse clinical and neuropathological features. In vivo neuropathological assessments of frontotemporal dementia at an individual level have hitherto not been successful. In this study, we aim to classify patients with frontotemporal dementia based on topologies of tau protein aggregates captured by PET with 18F-florzolotau (aka 18F-APN-1607 and 18F-PM-PBB3), which allows high-contrast imaging of diverse tau fibrils in Alzheimer's disease as well as in non-Alzheimer's disease tauopathies. Twenty-six patients with frontotemporal dementia, 15 with behavioural variant frontotemporal dementia and 11 with other frontotemporal dementia phenotypes, and 20 age- and sex-matched healthy controls were included in this study. They underwent PET imaging of amyloid and tau depositions with 11C-PiB and 18F-florzolotau, respectively. By combining visual and quantitative analyses of PET images, the patients with behavioural variant frontotemporal dementia were classified into the following subgroups: (i) predominant tau accumulations in frontotemporal and frontolimbic cortices resembling three-repeat tauopathies (n = 3), (ii) predominant tau accumulations in posterior cortical and subcortical structures indicative of four-repeat tauopathies (n = 4); (iii) amyloid and tau accumulations consistent with Alzheimer's disease (n = 4); and (iv) no overt amyloid and tau pathologies (n = 4). Despite these distinctions, clinical symptoms and localizations of brain atrophy did not significantly differ among the identified behavioural variant frontotemporal dementia subgroups. The patients with other frontotemporal dementia phenotypes were also classified into similar subgroups. The results suggest that PET with 18F-florzolotau potentially allows the classification of each individual with frontotemporal dementia on a neuropathological basis, which might not be possible by symptomatic and volumetric assessments.
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Affiliation(s)
- Manabu Kubota
- Department of Functional Brain Imaging, Institute for Quantum Medical Science, Quantum Life and Medical Science Directorate, National Institutes for Quantum Science and Technology, Chiba 263-8555, Japan
- Department of Psychiatry, Kyoto University Graduate School of Medicine, Sakyo-ku Kyoto 606-8507, Japan
| | - Hironobu Endo
- Department of Functional Brain Imaging, Institute for Quantum Medical Science, Quantum Life and Medical Science Directorate, National Institutes for Quantum Science and Technology, Chiba 263-8555, Japan
| | - Keisuke Takahata
- Department of Functional Brain Imaging, Institute for Quantum Medical Science, Quantum Life and Medical Science Directorate, National Institutes for Quantum Science and Technology, Chiba 263-8555, Japan
- Department of Neuropsychiatry, Keio University School of Medicine, Tokyo 160-8582, Japan
| | - Kenji Tagai
- Department of Functional Brain Imaging, Institute for Quantum Medical Science, Quantum Life and Medical Science Directorate, National Institutes for Quantum Science and Technology, Chiba 263-8555, Japan
- Department of Psychiatry, Jikei University Graduate School of Medicine, Tokyo 105-8461, Japan
| | - Hisaomi Suzuki
- Department of Functional Brain Imaging, Institute for Quantum Medical Science, Quantum Life and Medical Science Directorate, National Institutes for Quantum Science and Technology, Chiba 263-8555, Japan
- Department of Psychiatry, National Hospital OrganizationShimofusa Psychiatric Center, Chiba 266-0007, Japan
| | - Mitsumoto Onaya
- Department of Psychiatry, National Hospital OrganizationShimofusa Psychiatric Center, Chiba 266-0007, Japan
| | - Yasunori Sano
- Department of Functional Brain Imaging, Institute for Quantum Medical Science, Quantum Life and Medical Science Directorate, National Institutes for Quantum Science and Technology, Chiba 263-8555, Japan
- Department of Neuropsychiatry, Keio University School of Medicine, Tokyo 160-8582, Japan
| | - Yasuharu Yamamoto
- Department of Functional Brain Imaging, Institute for Quantum Medical Science, Quantum Life and Medical Science Directorate, National Institutes for Quantum Science and Technology, Chiba 263-8555, Japan
- Department of Neuropsychiatry, Keio University School of Medicine, Tokyo 160-8582, Japan
| | - Shin Kurose
- Department of Functional Brain Imaging, Institute for Quantum Medical Science, Quantum Life and Medical Science Directorate, National Institutes for Quantum Science and Technology, Chiba 263-8555, Japan
- Department of Neuropsychiatry, Keio University School of Medicine, Tokyo 160-8582, Japan
| | - Kiwamu Matsuoka
- Department of Functional Brain Imaging, Institute for Quantum Medical Science, Quantum Life and Medical Science Directorate, National Institutes for Quantum Science and Technology, Chiba 263-8555, Japan
- Department of Psychiatry, Nara Medical University, Nara 634-8521, Japan
| | - Chie Seki
- Department of Functional Brain Imaging, Institute for Quantum Medical Science, Quantum Life and Medical Science Directorate, National Institutes for Quantum Science and Technology, Chiba 263-8555, Japan
| | - Hitoshi Shinotoh
- Department of Functional Brain Imaging, Institute for Quantum Medical Science, Quantum Life and Medical Science Directorate, National Institutes for Quantum Science and Technology, Chiba 263-8555, Japan
| | - Kazunori Kawamura
- Department of Advanced Nuclear Medicine Sciences, Institute for Quantum Medical Science, Quantum Life and Medical Science Directorate, National Institutes for Quantum Science and Technology, Chiba 263-8555, Japan
| | - Ming-Rong Zhang
- Department of Advanced Nuclear Medicine Sciences, Institute for Quantum Medical Science, Quantum Life and Medical Science Directorate, National Institutes for Quantum Science and Technology, Chiba 263-8555, Japan
| | - Yuhei Takado
- Department of Functional Brain Imaging, Institute for Quantum Medical Science, Quantum Life and Medical Science Directorate, National Institutes for Quantum Science and Technology, Chiba 263-8555, Japan
| | - Hitoshi Shimada
- Department of Functional Brain Imaging, Institute for Quantum Medical Science, Quantum Life and Medical Science Directorate, National Institutes for Quantum Science and Technology, Chiba 263-8555, Japan
- Department of Functional Neurology and Neurosurgery, Center for Integrated Human Brain Science, Brain Research Institute, Niigata University, Niigata 951-8585, Japan
| | - Makoto Higuchi
- Department of Functional Brain Imaging, Institute for Quantum Medical Science, Quantum Life and Medical Science Directorate, National Institutes for Quantum Science and Technology, Chiba 263-8555, Japan
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Graham TJA, Lindberg A, Tong J, Stehouwer JS, Vasdev N, Mach RH, Mathis CA. In Silico Discovery and Subsequent Characterization of Potent 4R-Tauopathy Positron Emission Tomography Radiotracers. J Med Chem 2023; 66:10628-10638. [PMID: 37487189 PMCID: PMC10424182 DOI: 10.1021/acs.jmedchem.3c00775] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Indexed: 07/26/2023]
Abstract
A chemical fingerprint search identified Z3777013540 (1-(5-(6-fluoro-1H-indol-2-yl)pyrimidin-2-yl)piperidin-4-ol; 1) as a potential 4R-tau binding ligand. Binding assays in post-mortem Alzheimer's disease (AD), progressive supranuclear palsy (PSP), and corticobasal degeneration (CBD) brain with [3H]1 provided KD (nM) values in AD = 4.0, PSP = 5.1, and CBD = 4.5. In vivo positron emission tomography (PET) imaging in rats with [18F]1 demonstrated good brain penetration and rapid clearance from normal brain tissues. A subsequent molecular similarity search using 1 as the query revealed an additional promising compound, Z4169252340 (4-(5-(6-fluoro-1H-indol-2-yl)pyrimidin-2-yl)morpholine; 21). Binding assays with [3H]21 provided KD (nM) values in AD = 1.2, PSP = 1.6, and CBD = 1.7 and lower affinities for binding aggregated α-synuclein and amyloid-beta. PET imaging in rats with [18F]21 demonstrated a higher brain penetration than [18F]1 and rapid clearance from normal brain tissues. We anticipate that 1 and 21 will be useful for the identification of other potent novel 4R-tau radiotracers.
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Affiliation(s)
- Thomas J. A. Graham
- Department
of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6323, United
States
| | - Anton Lindberg
- Azrieli
Centre for Neuro-Radiochemistry, Brain Health Imaging Centre, Centre for Addiction and Mental Health, Toronto, Ontario M5T 1R8, Canada
| | - Junchao Tong
- Azrieli
Centre for Neuro-Radiochemistry, Brain Health Imaging Centre, Centre for Addiction and Mental Health, Toronto, Ontario M5T 1R8, Canada
| | - Jeffrey S. Stehouwer
- Department
of Radiology, University of Pittsburgh, Pittsburgh, Pennsylvania 15213, United States
| | - Neil Vasdev
- Azrieli
Centre for Neuro-Radiochemistry, Brain Health Imaging Centre, Centre for Addiction and Mental Health, Toronto, Ontario M5T 1R8, Canada
- Department
of Psychiatry, University of Toronto, Toronto, Ontario M5T 1R8, Canada
| | - Robert H. Mach
- Department
of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6323, United
States
| | - Chester A. Mathis
- Department
of Radiology, University of Pittsburgh, Pittsburgh, Pennsylvania 15213, United States
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Varlow C, Vasdev N. Evaluation of Tau Radiotracers in Chronic Traumatic Encephalopathy. J Nucl Med 2023; 64:460-465. [PMID: 36109185 PMCID: PMC10071800 DOI: 10.2967/jnumed.122.264404] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2022] [Revised: 09/06/2022] [Accepted: 09/06/2022] [Indexed: 11/16/2022] Open
Abstract
Chronic traumatic encephalopathy (CTE) is a neurologic disorder associated with head injuries, diagnosed by the perivascular accumulation of hyperphosphorylated tau protein (phospho-tau) identified at autopsy. Tau PET radiopharmaceuticals developed for imaging Alzheimer disease are under evaluation for brain injuries. The goal of this study was to conduct a head-to-head in vitro evaluation of 5 tau PET radiotracers in subjects pathologically diagnosed with CTE. Methods: Autoradiography was used to assess the specific binding and distribution of 3H-flortaucipir (also known as Tauvid, AV-1451, and T807), 3H-MK-6240 (also known as florquinitau), 3H-PI-2620, 3H-APN-1607 (also known as PM-PBB3 and florzolotau), and 3H-CBD-2115 (also known as 3H-OXD-2115) in fresh-frozen human postmortem CTE brain tissue (stages I-IV). Immunohistochemistry was performed for phospho-tau with AT8, 3R tau with RD3, 4R tau with RD4 and amyloid-β with 6F/3D antibodies. Tau target density (maximum specific binding) was quantified by saturation analysis with 3H-flortaucipir in tissue sections. Results: 3H-flortaucipir demonstrated a positive signal in all CTE cases examined, with varying degrees of specific binding (68.7% ± 10.5%; n = 12) defined by homologous blockade and to a lesser extent by heterologous blockade with MK-6240 (27.3% ± 13.6%; n = 12). The 3H-flortaucipir signal was also displaced by the monoamine oxidase (MAO)-A inhibitor clorgyline (43.9% ± 4.6%; n = 3), indicating off-target binding to MAO-A. 3H-APN-1607 was moderately displaced in homologous blocking studies and was not displaced by 3H-flortaucipir; however, substantial displacement was observed when blocking with the β-amyloid-targeting compound NAV-4694. 3H-MK-6240 and 3H-PI-2620 had negligible binding in all but 2 CTE IV cases, and binding may be attributed to pathology severity or mixed Alzheimer disease/CTE pathology. 3H-CBD-2115 showed moderate binding, displaced under homologous blockade, and aligned with 4R-tau immunostaining. Conclusion: In human CTE tissues, 3H-flortaucipir and 3H-APN-1607 revealed off-target binding to MAO-A and amyloid-β, respectively, and should be considered if these radiotracers are used in PET imaging studies of patients with brain injuries. 3H-MK-6240 and 3H-PI-2620 bind to CTE tau in severe- or mixed-pathology cases, and their respective 18F PET radiotracers warrant further evaluation in patients with severe suspected CTE.
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Affiliation(s)
- Cassis Varlow
- Azrieli Centre for Neuro-Radiochemistry, Brain Health Imaging Centre, Centre for Addiction and Mental Health, and Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada
| | - Neil Vasdev
- Azrieli Centre for Neuro-Radiochemistry, Brain Health Imaging Centre, Centre for Addiction and Mental Health, and Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada
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Mohammadi Z, Alizadeh H, Marton J, Cumming P. The Sensitivity of Tau Tracers for the Discrimination of Alzheimer's Disease Patients and Healthy Controls by PET. Biomolecules 2023; 13:290. [PMID: 36830659 PMCID: PMC9953528 DOI: 10.3390/biom13020290] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Revised: 01/12/2023] [Accepted: 01/25/2023] [Indexed: 02/09/2023] Open
Abstract
Hyperphosphorylated tau aggregates, also known as neurofibrillary tangles, are a hallmark neuropathological feature of Alzheimer's disease (AD). Molecular imaging of tau by positron emission tomography (PET) began with the development of [18F]FDDNP, an amyloid β tracer with off-target binding to tau, which obtained regional specificity through the differing distributions of amyloid β and tau in AD brains. A concerted search for more selective and affine tau PET tracers yielded compounds belonging to at least eight structural categories; 18F-flortaucipir, known variously as [18F]-T807, AV-1451, and Tauvid®, emerged as the first tau tracer approved by the American Food and Drug Administration. The various tau tracers differ concerning their selectivity over amyloid β, off-target binding at sites such as monoamine oxidase and neuromelanin, and degree of uptake in white matter. While there have been many reviews of molecular imaging of tau in AD and other conditions, there has been no systematic comparison of the fitness of the various tracers for discriminating between AD patient and healthy control (HC) groups. In this narrative review, we endeavored to compare the binding properties of the various tau tracers in vitro and the effect size (Cohen's d) for the contrast by PET between AD patients and age-matched HC groups. The available tracers all gave good discrimination, with Cohen's d generally in the range of two-three in culprit brain regions. Overall, Cohen's d was higher for AD patient groups with more severe illness. Second-generation tracers, while superior concerning off-target binding, do not have conspicuously higher sensitivity for the discrimination of AD and HC groups. We suppose that available pharmacophores may have converged on a maximal affinity for tau fibrils, which may limit the specific signal imparted in PET studies.
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Affiliation(s)
- Zohreh Mohammadi
- Immunology Research Center, Tabriz University of Medical Sciences, Tabriz 5166/15731, Iran
- Student Research Committee, Tabriz University of Medical Sciences, Tabriz 5166/15731, Iran
| | - Hadi Alizadeh
- Immunology Research Center, Tabriz University of Medical Sciences, Tabriz 5166/15731, Iran
| | - János Marton
- ABX Advanced Biochemical Compounds Biomedizinische Forschungsreagenzien GmbH, Heinrich-Glaeser-Straße 10-14, D-01454 Radeberg, Germany
| | - Paul Cumming
- Department of Nuclear Medicine, Bern University Hospital, Freiburgstraße 18, CH-3010 Bern, Switzerland
- School of Psychology and Counselling, Queensland University of Technology, Brisbane, QLD 4059, Australia
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8
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Endo H, Tagai K, Ono M, Ikoma Y, Oyama A, Matsuoka K, Kokubo N, Hirata K, Sano Y, Oya M, Matsumoto H, Kurose S, Seki C, Shimizu H, Kakita A, Takahata K, Shinotoh H, Shimada H, Tokuda T, Kawamura K, Zhang M, Oishi K, Mori S, Takado Y, Higuchi M. A Machine Learning-Based Approach to Discrimination of Tauopathies Using [ 18 F]PM-PBB3 PET Images. Mov Disord 2022; 37:2236-2246. [PMID: 36054492 PMCID: PMC9805085 DOI: 10.1002/mds.29173] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2022] [Revised: 06/03/2022] [Accepted: 07/10/2022] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND We recently developed a positron emission tomography (PET) probe, [18 F]PM-PBB3, to detect tau lesions in diverse tauopathies, including mixed three-repeat and four-repeat (3R + 4R) tau fibrils in Alzheimer's disease (AD) and 4R tau aggregates in progressive supranuclear palsy (PSP). For wider availability of this technology for clinical settings, bias-free quantitative evaluation of tau images without a priori disease information is needed. OBJECTIVE We aimed to establish tau PET pathology indices to characterize PSP and AD using a machine learning approach and test their validity and tracer capabilities. METHODS Data were obtained from 50 healthy control subjects, 46 patients with PSP Richardson syndrome, and 37 patients on the AD continuum. Tau PET data from 114 regions of interest were subjected to Elastic Net cross-validation linear classification analysis with a one-versus-the-rest multiclass strategy to obtain a linear function that discriminates diseases by maximizing the area under the receiver operating characteristic curve. We defined PSP- and AD-tau scores for each participant as values of the functions optimized for differentiating PSP (4R) and AD (3R + 4R), respectively, from others. RESULTS The discriminatory ability of PSP- and AD-tau scores assessed as the area under the receiver operating characteristic curve was 0.98 and 1.00, respectively. PSP-tau scores correlated with the PSP rating scale in patients with PSP, and AD-tau scores correlated with Mini-Mental State Examination scores in healthy control-AD continuum patients. The globus pallidus and amygdala were highlighted as regions with high weight coefficients for determining PSP- and AD-tau scores, respectively. CONCLUSIONS These findings highlight our technology's unbiased capability to identify topologies of 3R + 4R versus 4R tau deposits. © 2022 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.
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Affiliation(s)
- Hironobu Endo
- Institute for Quantum Medical Science, Quantum Life and Medical Science DirectorateNational Institutes for Quantum Science and TechnologyChibaJapan
| | - Kenji Tagai
- Institute for Quantum Medical Science, Quantum Life and Medical Science DirectorateNational Institutes for Quantum Science and TechnologyChibaJapan
| | - Maiko Ono
- Institute for Quantum Medical Science, Quantum Life and Medical Science DirectorateNational Institutes for Quantum Science and TechnologyChibaJapan
| | - Yoko Ikoma
- Institute for Quantum Medical Science, Quantum Life and Medical Science DirectorateNational Institutes for Quantum Science and TechnologyChibaJapan
| | - Asaka Oyama
- Institute for Quantum Medical Science, Quantum Life and Medical Science DirectorateNational Institutes for Quantum Science and TechnologyChibaJapan
| | - Kiwamu Matsuoka
- Institute for Quantum Medical Science, Quantum Life and Medical Science DirectorateNational Institutes for Quantum Science and TechnologyChibaJapan
| | - Naomi Kokubo
- Institute for Quantum Medical Science, Quantum Life and Medical Science DirectorateNational Institutes for Quantum Science and TechnologyChibaJapan
| | - Kosei Hirata
- Institute for Quantum Medical Science, Quantum Life and Medical Science DirectorateNational Institutes for Quantum Science and TechnologyChibaJapan
| | - Yasunori Sano
- Institute for Quantum Medical Science, Quantum Life and Medical Science DirectorateNational Institutes for Quantum Science and TechnologyChibaJapan
| | - Masaki Oya
- Institute for Quantum Medical Science, Quantum Life and Medical Science DirectorateNational Institutes for Quantum Science and TechnologyChibaJapan
| | - Hideki Matsumoto
- Institute for Quantum Medical Science, Quantum Life and Medical Science DirectorateNational Institutes for Quantum Science and TechnologyChibaJapan,Department of Oral and Maxillofacial RadiologyTokyo Dental CollegeTokyoJapan
| | - Shin Kurose
- Institute for Quantum Medical Science, Quantum Life and Medical Science DirectorateNational Institutes for Quantum Science and TechnologyChibaJapan
| | - Chie Seki
- Institute for Quantum Medical Science, Quantum Life and Medical Science DirectorateNational Institutes for Quantum Science and TechnologyChibaJapan
| | - Hiroshi Shimizu
- Department of Pathology, Brain Research InstituteNiigata UniversityNiigataJapan
| | - Akiyoshi Kakita
- Department of Pathology, Brain Research InstituteNiigata UniversityNiigataJapan
| | - Keisuke Takahata
- Institute for Quantum Medical Science, Quantum Life and Medical Science DirectorateNational Institutes for Quantum Science and TechnologyChibaJapan
| | | | - Hitoshi Shimada
- Department of Functional Neurology & Neurosurgery, Center for Integrated Human Brain Science, Brain Research InstituteNiigata UniversityNiigataJapan
| | - Takahiko Tokuda
- Institute for Quantum Medical Science, Quantum Life and Medical Science DirectorateNational Institutes for Quantum Science and TechnologyChibaJapan
| | - Kazunori Kawamura
- Institute for Quantum Medical Science, Quantum Life and Medical Science DirectorateNational Institutes for Quantum Science and TechnologyChibaJapan
| | - Ming‐Rong Zhang
- Institute for Quantum Medical Science, Quantum Life and Medical Science DirectorateNational Institutes for Quantum Science and TechnologyChibaJapan
| | - Kenichi Oishi
- The Russell H. Morgan Department of Radiology and Radiological ScienceJohns Hopkins University School of MedicineBaltimoreMarylandUSA
| | - Susumu Mori
- The Russell H. Morgan Department of Radiology and Radiological ScienceJohns Hopkins University School of MedicineBaltimoreMarylandUSA
| | - Yuhei Takado
- Institute for Quantum Medical Science, Quantum Life and Medical Science DirectorateNational Institutes for Quantum Science and TechnologyChibaJapan
| | - Makoto Higuchi
- Institute for Quantum Medical Science, Quantum Life and Medical Science DirectorateNational Institutes for Quantum Science and TechnologyChibaJapan
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9
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Disclosing tau tangles using PET imaging: a pharmacological review of the radiotracers available in 2021. Acta Neurol Belg 2022; 122:263-272. [PMID: 34713414 DOI: 10.1007/s13760-021-01797-w] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Accepted: 09/06/2021] [Indexed: 11/27/2022]
Abstract
Neurological symptoms depend on the topography of the lesions in the nervous system, hence the importance of brain imaging for neurologists. Neurological treatment, however, depends on the biological nature of the lesions. The development of radiotracers specific for the proteinopathies observed in neurodegenerative disorders is, therefore, crucially important for better understanding the relationships between the pathology and the clinical symptoms, as well as the efficacy of therapeutical interventions. The tau protein is involved in several neurodegenerative disorders, that can be distinguished both biologically and clinically as the type of tau isoforms and filaments observed in brain aggregates, and the brain regions affected differ between tauopathies. Over the past few years, several tracers have been developed for imaging tauopathies with positron emission tomography. The present review aims to compare the binding properties of these tracers, with a specific focus on how these properties might be relevant for neurologists using these biomarkers to characterize the pathology of patients presenting with clinical symptoms suspect of a neurodegenerative disorder.
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10
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Kawamura K, Hashimoto H, Ohkubo T, Hanyu M, Ogawa M, Nengaki N, Arashi D, Kurihara Y, Fujishiro T, Togashi T, Sakai T, Muto M, Takei M, Ishii H, Saijo T, Matsumura T, Obokata N, Zhang MR. Automated radiosynthesis of [ 11 C]MTP38-a phosphodiesterase 7 imaging tracer-using [ 11 C]hydrogen cyanide for clinical applications. J Labelled Comp Radiopharm 2022; 65:140-146. [PMID: 35122288 DOI: 10.1002/jlcr.3965] [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: 12/13/2021] [Revised: 01/27/2022] [Accepted: 01/28/2022] [Indexed: 11/11/2022]
Abstract
We have developed 8-amino-3-(2S,5R-dimethyl-1-piperidyl)-[1,2,4]triazolo[4,3-a]pyrazine-5-[11 C]carbonitrile ([11 C]MTP38) as a PET tracer for the imaging of phosphodiesterase 7. For the fully automated production of [11 C]MTP38 routinely and efficiently for clinical applications, we determined the radiosynthesis procedure of [11 C]MTP38 using [11 C]hydrogen cyanide ([11 C]HCN) as a PET radiopharmaceutical. Radiosynthesis of [11 C]MTP38 was performed using an automated 11 C-labeling synthesizer developed in-house within 40 min after the end of irradiation. [11 C]MTP38 was obtained with a relatively high radiochemical yield (33 ± 5.5% based on [11 C]CO2 at the end of irradiation, decay-corrected, n = 15), radiochemical purity (>97%, n = 15), and molar activity (47 ± 12 GBq/μmol at the end of synthesis, n = 15). All the results of the quality control (QC) testing for the [11 C]MTP38 injection complied with our in-house QC and quality assurance specifications. We successfully automated the radiosynthesis of [11 C]MTP38 for clinical applications using an 11 C-labeling synthesizer and sterile isolator. Taken together, this protocol provides a new radiopharmaceutical [11 C]MTP38 suitable for clinical applications.
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Affiliation(s)
- Kazunori Kawamura
- Department of Advanced Nuclear Medicine Sciences, Institute for Quantum Medical Science, National Institutes for Quantum Science and Technology, Chiba, Japan
| | - Hiroki Hashimoto
- Department of Advanced Nuclear Medicine Sciences, Institute for Quantum Medical Science, National Institutes for Quantum Science and Technology, Chiba, Japan
| | - Takayuki Ohkubo
- Department of Advanced Nuclear Medicine Sciences, Institute for Quantum Medical Science, National Institutes for Quantum Science and Technology, Chiba, Japan.,SHI Accelerator Service Ltd., Tokyo, Japan
| | - Masayuki Hanyu
- Department of Advanced Nuclear Medicine Sciences, Institute for Quantum Medical Science, National Institutes for Quantum Science and Technology, Chiba, Japan
| | - Masanao Ogawa
- Department of Advanced Nuclear Medicine Sciences, Institute for Quantum Medical Science, National Institutes for Quantum Science and Technology, Chiba, Japan.,SHI Accelerator Service Ltd., Tokyo, Japan
| | - Nobuki Nengaki
- Department of Advanced Nuclear Medicine Sciences, Institute for Quantum Medical Science, National Institutes for Quantum Science and Technology, Chiba, Japan.,SHI Accelerator Service Ltd., Tokyo, Japan
| | - Daisuke Arashi
- Department of Advanced Nuclear Medicine Sciences, Institute for Quantum Medical Science, National Institutes for Quantum Science and Technology, Chiba, Japan.,Tokyo Nuclear Services Ltd., Tokyo, Japan
| | - Yusuke Kurihara
- Department of Advanced Nuclear Medicine Sciences, Institute for Quantum Medical Science, National Institutes for Quantum Science and Technology, Chiba, Japan.,SHI Accelerator Service Ltd., Tokyo, Japan
| | - Tomoya Fujishiro
- Department of Advanced Nuclear Medicine Sciences, Institute for Quantum Medical Science, National Institutes for Quantum Science and Technology, Chiba, Japan.,Tokyo Nuclear Services Ltd., Tokyo, Japan
| | - Takahiro Togashi
- Department of Advanced Nuclear Medicine Sciences, Institute for Quantum Medical Science, National Institutes for Quantum Science and Technology, Chiba, Japan.,Tokyo Nuclear Services Ltd., Tokyo, Japan
| | - Toshiyuki Sakai
- Department of Advanced Nuclear Medicine Sciences, Institute for Quantum Medical Science, National Institutes for Quantum Science and Technology, Chiba, Japan.,Tokyo Nuclear Services Ltd., Tokyo, Japan
| | - Masatoshi Muto
- Department of Advanced Nuclear Medicine Sciences, Institute for Quantum Medical Science, National Institutes for Quantum Science and Technology, Chiba, Japan.,Tokyo Nuclear Services Ltd., Tokyo, Japan
| | - Makoto Takei
- Department of Advanced Nuclear Medicine Sciences, Institute for Quantum Medical Science, National Institutes for Quantum Science and Technology, Chiba, Japan
| | - Hideki Ishii
- Department of Advanced Nuclear Medicine Sciences, Institute for Quantum Medical Science, National Institutes for Quantum Science and Technology, Chiba, Japan
| | - Takeaki Saijo
- Sohyaku Innovative Research Division, Mitsubishi Tanabe Pharma Corporation, Yokohama, Japan
| | - Takehiko Matsumura
- Sohyaku Innovative Research Division, Mitsubishi Tanabe Pharma Corporation, Yokohama, Japan
| | - Naoyuki Obokata
- Sohyaku Innovative Research Division, Mitsubishi Tanabe Pharma Corporation, Yokohama, Japan
| | - Ming-Rong Zhang
- Department of Advanced Nuclear Medicine Sciences, Institute for Quantum Medical Science, National Institutes for Quantum Science and Technology, Chiba, Japan
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11
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Mena AM, Strafella AP. Imaging pathological tau in atypical parkinsonisms: A review. Clin Park Relat Disord 2022; 7:100155. [PMID: 35880206 PMCID: PMC9307942 DOI: 10.1016/j.prdoa.2022.100155] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2022] [Revised: 06/06/2022] [Accepted: 07/07/2022] [Indexed: 11/27/2022] Open
Abstract
[18F]AV-1451 displays mixed results for specificity to 4R CBD- and PSP-tau. [18F]PI-2620 and [18F]PM-PBB3 are the most promising second-generation tau PET tracers. Research using second-generation tau PET tracers in CBD and PSP is still limited. Finding an imaging diagnostic biomarker requires further work with larger samples.
Atypical parkinsonisms (APs) are a group of diseases linked to tau pathology. These include progressive supranuclear palsy (PSP) and corticobasal degeneration (CBD). In the initial stages, these APs may have similar clinical manifestations to Parkinson’s disease (PD) and other parkinsonisms: bradykinesia, postural instability, tremor, and cognitive decline. Because of this, one major hurdle is the accurate early diagnosis of APs. Recent advances in positron emission tomography (PET) radiotracer development have allowed for targeting pathological tau in Alzheimer’s disease (AD). Currently, work is still in progress for identifying a first-in-class radiotracer for imaging tau in APs. In this review, we evaluate the literature on in vitro and in vivo testing of current tau PET radiotracers in APs. The tau PET tracers assessed include both first-generation tracers ([18F]AV-1451, [18F]FDDNP, [18F]THK derivatives, and [11C]PBB3) and second-generation tracers ([18F]PM-PBB3, [18F]PI-2620, [18F]RO-948, [18F]JNJ-067, [18F]MK-6240, and [18F]CBD-2115). Concerns regarding off-target binding to cerebral white matter and the basal ganglia are still prominent with first-generation tracers, but this seems to have been mediated in a handful of second-generation tracers, including [18F]PI-2620 and [18F]PM-PBB3. Additionally, these two tracers and [18F]MK-6240 show promising results for imaging PSP- and CBD-tau. Overall, [18F]AV-1451 is the most widely studied tracer but the mixed results regarding its efficacy for use in imaging AP-tau is a cause for concern moving forward. Instead, future work may benefit from focusing on the second-generation radiotracers which seem to have a higher specificity for AP-tau than those originally developed for imaging AD-tau.
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12
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Levy JP, Bezgin G, Savard M, Pascoal TA, Finger E, Laforce R, Sonnen JA, Soucy JP, Gauthier S, Rosa-Neto P, Ducharme S. 18F-MK-6240 tau-PET in genetic frontotemporal dementia. Brain 2021; 145:1763-1772. [PMID: 34664612 PMCID: PMC9166561 DOI: 10.1093/brain/awab392] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Revised: 08/25/2021] [Accepted: 09/10/2021] [Indexed: 11/28/2022] Open
Abstract
Tau is one of several proteins associated with frontotemporal dementia. While knowing which protein is causing a patient’s disease is crucial, no biomarker currently exists for identifying tau in vivo in frontotemporal dementia. The objective of this study was to investigate the potential for the promising 18F-MK-6240 PET tracer to bind to tau in vivo in genetic frontotemporal dementia. We enrolled subjects with genetic frontotemporal dementia, who constitute an ideal population for testing because their pathology is already known based on their mutation. Ten participants (three with symptomatic P301L and R406W MAPT mutations expected to show tau binding, three with presymptomatic MAPT mutations and four with non-tau mutations who acted as disease controls) underwent clinical characterization, tau-PET scanning with 18F-MK-6240, amyloid-PET imaging with 18F-NAV-4694 to rule out confounding Alzheimer’s pathology, and high-resolution structural MRI. Tau-PET scans of all three symptomatic MAPT carriers demonstrated at least mild 18F-MK-6240 binding in expected regions, with particularly strong binding in a subject with an R406W MAPT mutation (known to be associated with Alzheimer’s like neurofibrillary tangles). Two asymptomatic MAPT carriers estimated to be 5 years from disease onset both showed modest 18F-MK-6240 binding, while one ∼30 years from disease onset did not exhibit any binding. Additionally, four individuals with symptomatic frontotemporal dementia caused by a non-tau mutation were scanned (two C9orf72; one GRN; one VCP): 18F-MK-6240 scans were negative for three subjects, while one advanced C9orf72 case showed minimal regionally non-specific binding. All 10 amyloid-PET scans were negative. Furthermore, a general linear model contrasting genetic frontotemporal dementia subjects to a set of 83 age-matched controls showed significant binding only in the MAPT carriers in selected frontal, temporal and subcortical regions. In summary, our findings demonstrate mild but significant binding of MK-6240 in amyloid-negative P301L and R406W MAPT mutation subjects, with higher standardized uptake value ratio in the R406W mutation associated with the presence of NFTs, and little non-specific binding. These results highlight that a positive 18F-MK-6240 tau-PET does not necessarily imply a diagnosis of Alzheimer’s disease and point towards a potential use for 18F-MK-6240 as a biomarker in certain tauopathies beyond Alzheimer’s, although further patient recruitment and autopsy studies will be necessary to determine clinical applicability.
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Affiliation(s)
- Jake P Levy
- McConnell Brain Imaging Centre, Montreal Neurological Institute, McGill University, Montreal, QC H3A 2B4, Canada
| | - Gleb Bezgin
- Translational Neuroimaging Laboratory, The McGill University Research Centre for Studies in Aging, Montreal, QC H4H 1R3, Canada
| | - Melissa Savard
- Translational Neuroimaging Laboratory, The McGill University Research Centre for Studies in Aging, Montreal, QC H4H 1R3, Canada
| | - Tharick A Pascoal
- Translational Neuroimaging Laboratory, The McGill University Research Centre for Studies in Aging, Montreal, QC H4H 1R3, Canada
| | - Elizabeth Finger
- Department of Clinical Neurological Sciences, Schulich School of Medicine and Dentistry, Parkwood Institute, Lawson Health Research Institute, University of Western Ontario, London, ON, Canada
| | - Robert Laforce
- Clinique Interdisciplinaire de Mémoire, Département des Sciences Neurologiques du CHU de Québec, Faculté de Médecine, Université Laval, QC, Canada
| | - Joshua A Sonnen
- Departments of Pathology, Neurology and Neurosurgery, Montreal Neurological Institute, McGill University
| | - Jean-Paul Soucy
- McConnell Brain Imaging Centre, Montreal Neurological Institute, McGill University, Montreal, QC H3A 2B4, Canada
| | - Serge Gauthier
- Translational Neuroimaging Laboratory, The McGill University Research Centre for Studies in Aging, Montreal, QC H4H 1R3, Canada
| | - Pedro Rosa-Neto
- McConnell Brain Imaging Centre, Montreal Neurological Institute, McGill University, Montreal, QC H3A 2B4, Canada.,Translational Neuroimaging Laboratory, The McGill University Research Centre for Studies in Aging, Montreal, QC H4H 1R3, Canada
| | - Simon Ducharme
- McConnell Brain Imaging Centre, Montreal Neurological Institute, McGill University, Montreal, QC H3A 2B4, Canada.,Douglas Mental Health University Institute, Department of Psychiatry, Montreal, QC H4H 1R3, Canada
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13
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Ohkubo T, Kurihara Y, Ogawa M, Nengaki N, Fujinaga M, Mori W, Kumata K, Hanyu M, Furutsuka K, Hashimoto H, Kawamura K, Zhang MR. Automated radiosynthesis of two 18F-labeled tracers containing 3-fluoro-2-hydroxypropyl moiety, [ 18F]FMISO and [ 18F]PM-PBB3, via [ 18F]epifluorohydrin. EJNMMI Radiopharm Chem 2021; 6:23. [PMID: 34245396 PMCID: PMC8272768 DOI: 10.1186/s41181-021-00138-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Accepted: 06/09/2021] [Indexed: 12/17/2022] Open
Abstract
Background [18F]Fluoromisonidazole ([18F]FMISO) and 1-[18F]fluoro-3-((2-((1E,3E)-4-(6-(methylamino)pyridine-3-yl)buta-1,3-dien-1-yl)benzo[d]thiazol-6-yl)oxy)propan-2-ol ([18F]PM-PBB3 or [18F]APN-1607) are clinically used radiotracers for imaging hypoxia and tau pathology, respectively. Both radiotracers were produced by direct 18F-fluorination using the corresponding tosylate precursors 1 or 2 and [18F]F−, followed by the removal of protecting groups. In this study, we synthesized [18F]FMISO and [18F]PM-PBB3 by 18F-fluoroalkylation using [18F]epifluorohydrin ([18F]5) for clinical applications. Results First, [18F]5 was synthesized by the reaction of 1,2-epoxypropyl tosylate (8) with [18F]F− and was purified by distillation. Subsequently, [18F]5 was reacted with 2-nitroimidazole (6) or PBB3 (7) as a precursor for 18F-labeling, and each reaction mixture was purified by preparative high-performance liquid chromatography and formulated to obtain the [18F]FMISO or [18F]PM-PBB3 injection. All synthetic sequences were performed using an automated 18F-labeling synthesizer. The obtained [18F]FMISO showed sufficient radioactivity (0.83 ± 0.20 GBq at the end of synthesis (EOS); n = 8) with appropriate radiochemical yield based on [18F]F− (26 ± 7.5 % at EOS, decay-corrected; n = 8). The obtained [18F]PM-PBB3 also showed sufficient radioactivity (0.79 ± 0.10 GBq at EOS; n = 11) with appropriate radiochemical yield based on [18F]F− (16 ± 3.2 % at EOS, decay-corrected; n = 11). Conclusions Both [18F]FMISO and [18F]PM-PBB3 injections were successfully synthesized with sufficient radioactivity by 18F-fluoroalkylation using [18F]5. Supplementary Information The online version contains supplementary material available at 10.1186/s41181-021-00138-9.
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Affiliation(s)
- Takayuki Ohkubo
- Department of Advanced Nuclear Medicine Sciences, Institute for Quantum Medical Science, National Institutes for Quantum and Radiological Science and Technology, 263-8555, Chiba, Japan.,SHI Accelerator Service Ltd, 141-0032, Tokyo, Japan
| | - Yusuke Kurihara
- Department of Advanced Nuclear Medicine Sciences, Institute for Quantum Medical Science, National Institutes for Quantum and Radiological Science and Technology, 263-8555, Chiba, Japan.,SHI Accelerator Service Ltd, 141-0032, Tokyo, Japan
| | - Masanao Ogawa
- Department of Advanced Nuclear Medicine Sciences, Institute for Quantum Medical Science, National Institutes for Quantum and Radiological Science and Technology, 263-8555, Chiba, Japan.,SHI Accelerator Service Ltd, 141-0032, Tokyo, Japan
| | - Nobuki Nengaki
- Department of Advanced Nuclear Medicine Sciences, Institute for Quantum Medical Science, National Institutes for Quantum and Radiological Science and Technology, 263-8555, Chiba, Japan.,SHI Accelerator Service Ltd, 141-0032, Tokyo, Japan
| | - Masayuki Fujinaga
- Department of Advanced Nuclear Medicine Sciences, Institute for Quantum Medical Science, National Institutes for Quantum and Radiological Science and Technology, 263-8555, Chiba, Japan
| | - Wakana Mori
- Department of Advanced Nuclear Medicine Sciences, Institute for Quantum Medical Science, National Institutes for Quantum and Radiological Science and Technology, 263-8555, Chiba, Japan
| | - Katsushi Kumata
- Department of Advanced Nuclear Medicine Sciences, Institute for Quantum Medical Science, National Institutes for Quantum and Radiological Science and Technology, 263-8555, Chiba, Japan
| | - Masayuki Hanyu
- Department of Advanced Nuclear Medicine Sciences, Institute for Quantum Medical Science, National Institutes for Quantum and Radiological Science and Technology, 263-8555, Chiba, Japan
| | | | - Hiroki Hashimoto
- Department of Advanced Nuclear Medicine Sciences, Institute for Quantum Medical Science, National Institutes for Quantum and Radiological Science and Technology, 263-8555, Chiba, Japan
| | - Kazunori Kawamura
- Department of Advanced Nuclear Medicine Sciences, Institute for Quantum Medical Science, National Institutes for Quantum and Radiological Science and Technology, 263-8555, Chiba, Japan.
| | - Ming-Rong Zhang
- Department of Advanced Nuclear Medicine Sciences, Institute for Quantum Medical Science, National Institutes for Quantum and Radiological Science and Technology, 263-8555, Chiba, Japan
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