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Sahara N, Higuchi M. Diagnostic and therapeutic targeting of pathological tau proteins in neurodegenerative disorders. FEBS Open Bio 2024; 14:165-180. [PMID: 37746832 PMCID: PMC10839408 DOI: 10.1002/2211-5463.13711] [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: 07/24/2023] [Revised: 09/06/2023] [Accepted: 09/22/2023] [Indexed: 09/26/2023] Open
Abstract
Tauopathies, characterized by fibrillar tau accumulation in neurons and glial cells, constitute a major neuropathological category of neurodegenerative diseases. Neurofibrillary tau lesions are strongly associated with cognitive deficits in these diseases, but the causal mechanisms underlying tau-induced neuronal dysfunction remain unresolved. Recent advances in cryo-electron microscopy examination have revealed various core structures of tau filaments from different tauopathy patients, which can be used to classify tauopathies. In vivo visualization of tau pathology is now available using several tau positron emission tomography tracers. Among these radioprobes, PM-PBB3 allows high-contrast imaging of tau deposits in the brains of patients with diverse disorders and tauopathy mouse models. Selective degradation of pathological tau species by the ubiquitin-proteasome system or autophagy machinery is a potential therapeutic strategy. Alternatively, the non-cell-autonomous clearance of pathological tau species through neuron-glia networks could be reinforced as a disease-modifying treatment. In addition, the development of neuroinflammatory biomarkers is required for understanding the contribution of immunocompetent cells in the brain to preventing neurodegeneration. This review provides an overview of the current research and development of diagnostic and therapeutic agents targeting divergent tau pathologies.
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Affiliation(s)
- Naruhiko Sahara
- Department of Functional Brain Imaging, Institute for Quantum Medical SciencesNational Institutes for Quantum Science and TechnologyChibaJapan
| | - Makoto Higuchi
- Department of Functional Brain Imaging, Institute for Quantum Medical SciencesNational Institutes for Quantum Science and TechnologyChibaJapan
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2
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Myburgh PJ, Sai KKS. Development and Optimization of 11C-Labeled Radiotracers: A Review of the Modern Quality Control Design Process. ACS Pharmacol Transl Sci 2023; 6:1616-1631. [PMID: 37974626 PMCID: PMC10644505 DOI: 10.1021/acsptsci.3c00200] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2023] [Indexed: 11/19/2023]
Abstract
Introduction - Several 11C-tracers have demonstrated high potential in early diagnostic PET imaging applications of neurodegenerative diseases including Alzheimer's and Parkinson's disease. These radiotracers often track critical biomarkers in disease pathogenesis such as tau fibrils ([11C]PBB3) or β-amyloid plaques ([11C]PiB) associated with such diseases. Purpose - The short review aims to serve as a guideline in the future development of radiotracers for students, postdocs and/or new radiochemists who will be synthesizing clinical grade or novel research 11C-tracers, including knowledge of regulatory requirements. We aim to bridge the gap between novel and established 11C-tracer quality control (QC) processes through exploring the design process and regulatory requirements for 11C-pharmaceuticals. Methods - A literature survey was undertaken to identify articles with a detailed description of the QC methodology and characterization for each of the sections of the review. Overview - First a general summary of 11C-tracer production was presented; this was used to establish possible places for contamination or assurances for a sterile final product. The key mandated QC analyses for clinical use were then discussed. Further, we assessed the QC methods used for established 11C-tracers and then reviewed the routine QC tests for preclinical translational and validation studies. Therefore, both mandated QC methods for clinical and preclinical animal studies were reviewed. Last, some examples of optimization and automation were reviewed, and implications of the QC practices associated with such procedures were considered. Conclusion - All of the common QC parameters associated with 11C-tracers under clinical and preclinical settings (along with a few exceptions) were discussed in detail. While it is important to establish standard, peer-reviewed QC testing protocols for a novel 11C-tracer entering the clinical umbrella, equal importance is needed on preclinical applications to address credibility and repeatability for the study.
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Affiliation(s)
- Paul Josef Myburgh
- Translational
Imaging Program, Atrium Health Wake Forest
Baptist Medical Center, Winston-Salem, North Carolina 27157, United States
| | - Kiran Kumar Solingapuram Sai
- Translational
Imaging Program, Atrium Health Wake Forest
Baptist Medical Center, Winston-Salem, North Carolina 27157, United States
- Department
of Radiology, Atrium Health Wake Forest
Baptist Medical Center, Winston-Salem, North Carolina 27157, United States
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3
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Li J, Kumar A, Långström B, Nordberg A, Ågren H. Insight into the Binding of First- and Second-Generation PET Tracers to 4R and 3R/4R Tau Protofibrils. ACS Chem Neurosci 2023; 14:3528-3539. [PMID: 37639522 PMCID: PMC10515481 DOI: 10.1021/acschemneuro.3c00437] [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: 06/25/2023] [Accepted: 08/14/2023] [Indexed: 08/31/2023] Open
Abstract
Primary supranuclear palsy (PSP) is a rare neurodegenerative disease that perturbs body movement, eye movement, and walking balance. Similar to Alzheimer's disease (AD), the abnormal aggregation of tau fibrils in the central neuronal and glial cells is a major hallmark of PSP disease. In this study, we use multiple approaches, including docking, molecular dynamics, and metadynamics simulations, to investigate the binding mechanism of 10 first- and second-generations of PET tracers for PSP tau and compare their binding in cortical basal degeneration (CBD) and AD tauopathies. Structure-activity relationships, binding preferences, the nature of ligand binding in terms of basic intermolecular interactions, the role of polar/charged residues, induced-fit mechanisms, grove closures, and folding patterns for the binding of these tracers in PSP, CBD, and AD tau fibrils are evaluated and discussed in detail in order to build a holistic picture of what is essential for the binding and also to rank the potency of the different tracers. For example, we found that the same tracer shows different binding preferences for the surface sites of tau fibrils that are intrinsically distinct in the folding patterns. Results from the metadynamics simulations predict that PMPBB3 and PBB3 exhibit the strongest binding free energies onto the Q276[I277]I278, Q351[S352]K353, and N368[K369]K370 sites of PSP than the other explored tracers, indicating a solid preference for vdW and cation-π interactions. Our results also reproduced known preferences of tracers, namely, that MK6240 binds better to AD tau than CBD tau and PSP tau and that CBD2115, PI2620, and PMPBB3 are 4R tau binders. These findings fill in the well-sought-after knowledge gap in terms of these tracers' potential binding mechanisms and will be important for the design of highly selective novel PET tracers for tauopathies.
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Affiliation(s)
- Junhao Li
- Department
of Physics and Astronomy, Uppsala University, Box 516, SE-751 20 Uppsala, Sweden
| | - Amit Kumar
- Department
of Neurobiology, Care Sciences and Society, Division of Clinical Geriatrics, Center for Alzheimer Research, Neo, 141 84 Stockholm, Sweden
| | - Bengt Långström
- Department
of Chemistry - BMC, Uppsala University, Box 516, SE-751 20 Uppsala, Sweden
| | - Agneta Nordberg
- Department
of Neurobiology, Care Sciences and Society, Division of Clinical Geriatrics, Center for Alzheimer Research, Neo, 141 84 Stockholm, Sweden
- Theme
Inflammation and Aging, Karolinska University
Hospital, S-141 86 Stockholm, Sweden
| | - Hans Ågren
- Department
of Physics and Astronomy, Uppsala University, Box 516, SE-751 20 Uppsala, Sweden
- College
of Chemistry and Chemical Engineering, Henan
University, Kaifeng, Henan 475004, P. R. China
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4
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Villemagne VL, Leuzy A, Bohorquez SS, Bullich S, Shimada H, Rowe CC, Bourgeat P, Lopresti B, Huang K, Krishnadas N, Fripp J, Takado Y, Gogola A, Minhas D, Weimer R, Higuchi M, Stephens A, Hansson O, Doré V. CenTauR: Toward a universal scale and masks for standardizing tau imaging studies. ALZHEIMER'S & DEMENTIA (AMSTERDAM, NETHERLANDS) 2023; 15:e12454. [PMID: 37424964 PMCID: PMC10326476 DOI: 10.1002/dad2.12454] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Revised: 05/26/2023] [Accepted: 05/26/2023] [Indexed: 07/11/2023]
Abstract
INTRODUCTION Recently, an increasing number of tau tracers have become available. There is a need to standardize quantitative tau measures across tracers, supporting a universal scale. We developed several cortical tau masks and applied them to generate a tau imaging universal scale. METHOD One thousand forty-five participants underwent tau scans with either 18F-flortaucipir, 18F-MK6240, 18F-PI2620, 18F-PM-PBB3, 18F-GTP1, or 18F-RO948. The universal mask was generated from cognitively unimpaired amyloid beta (Aβ)- subjects and Alzheimer's disease (AD) patients with Aβ+. Four additional regional cortical masks were defined within the constraints of the universal mask. A universal scale, the CenTauRz, was constructed. RESULTS None of the regions known to display off-target signal were included in the masks. The CenTauRz allows robust discrimination between low and high levels of tau deposits. DISCUSSION We constructed several tau-specific cortical masks for the AD continuum and a universal standard scale designed to capture the location and degree of abnormality that can be applied across tracers and across centers. The masks are freely available at https://www.gaain.org/centaur-project.
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Affiliation(s)
- Victor L. Villemagne
- Department of PsychiatryUniversity of PittsburghPittsburghPennsylvaniaUSA
- Department of Molecular Imaging & TherapyAustin HealthMelbourneVictoriaAustralia
| | - Antoine Leuzy
- Clinical Memory Research UnitDepartment of Clinical SciencesLund UniversityMalmöSweden
| | | | | | - Hitoshi Shimada
- Department of Functional Brain ImagingNational Institutes for Quantum and Radiological Science and TechnologyChibaJapan
- Brain Research InstituteNiigata UniversityNiigataJapan
| | - Christopher C. Rowe
- Department of Molecular Imaging & TherapyAustin HealthMelbourneVictoriaAustralia
- Florey Department of Neurosciences & Mental HealthThe University of MelbourneMelbourneParkvilleAustralia
- The Australian Dementia Network (ADNeT)MelbourneVictoriaAustralia
| | - Pierrick Bourgeat
- Health and Biosecurity FlagshipThe Australian eHealth Research CentreCSIROBrisbaneQueenslandAustralia
| | - Brian Lopresti
- Department of RadiologyUniversity of PittsburghPittsburghPennsylvaniaUSA
| | - Kun Huang
- Department of Molecular Imaging & TherapyAustin HealthMelbourneVictoriaAustralia
| | - Natasha Krishnadas
- Department of Molecular Imaging & TherapyAustin HealthMelbourneVictoriaAustralia
- Florey Institute of Neurosciences & Mental HealthParkvilleVictoriaAustralia
| | - Jurgen Fripp
- Health and Biosecurity FlagshipThe Australian eHealth Research CentreCSIROBrisbaneQueenslandAustralia
| | - Yuhei Takado
- Department of Functional Brain ImagingNational Institutes for Quantum and Radiological Science and TechnologyChibaJapan
| | - Alexandra Gogola
- Department of RadiologyUniversity of PittsburghPittsburghPennsylvaniaUSA
| | - Davneet Minhas
- Department of RadiologyUniversity of PittsburghPittsburghPennsylvaniaUSA
| | | | - Makoto Higuchi
- Department of Functional Brain ImagingNational Institutes for Quantum and Radiological Science and TechnologyChibaJapan
| | | | - Oskar Hansson
- Clinical Memory Research UnitDepartment of Clinical SciencesLund UniversityMalmöSweden
- Memory ClinicSkåne University HospitalMalmöSweden
| | - Vincent Doré
- Department of Molecular Imaging & TherapyAustin HealthMelbourneVictoriaAustralia
- Health and Biosecurity FlagshipThe Australian eHealth Research CentreCSIROHeidelbergVictoriaAustralia
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5
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Luo Z, Li S, Zhang Y, Yin F, Luo H, Chen X, Cui N, Wan S, Li X, Kong L, Wang X. Oxazole-4-carboxamide/butylated hydroxytoluene hybrids with GSK-3β inhibitory and neuroprotective activities against Alzheimer's disease. Eur J Med Chem 2023; 256:115415. [PMID: 37172476 DOI: 10.1016/j.ejmech.2023.115415] [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: 02/24/2023] [Revised: 04/12/2023] [Accepted: 04/23/2023] [Indexed: 05/15/2023]
Abstract
Neuronal cells overexpressing phosphorylated Tau proteins can increase the susceptibility to oxidative stress. Regulation of glycogen synthase-3β (GSK-3β) and reduction of Tau protein hyperphosphorylation, along with alleviation of oxidative stress, may be an effective way to prevent or treat Alzheimer's disease (AD). For this purpose, a series of Oxazole-4-carboxamide/butylated hydroxytoluene hybrids were designed and synthesized to achieve multifunctional effects on AD. The biological evaluation showed that the optimized compound KWLZ-9e displayed potential GSK-3β (IC50 = 0.25 μM) inhibitory activity and neuroprotective capacity. Tau protein inhibition assays showed that KWLZ-9e reduced the expression of GSK-3β and downstream p-Tau in HEK GSK-3β 293T cells. Meanwhile, KWLZ-9e could alleviate H2O2-induced ROS damage, mitochondrial membrane potential imbalance, Ca2+ influx and apoptosis. Mechanistic studies suggest that KWLZ-9e activates the Keap1-Nrf2-ARE signaling pathway and enhances the expression of downstream oxidative stress proteins including TrxR1, HO-1, NQO1, GCLM to exert cytoprotective effects. We also confirmed that KWLZ-9e could ameliorate learning and memory impairments in vivo model of AD. The multifunctional properties of KWLZ-9e suggest that it is a promising lead for the treatment of AD.
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Affiliation(s)
- Zhongwen Luo
- Jiangsu Key Laboratory of Bioactive Natural Product Research and State Key Laboratory of Natural Medicines, Department of Natural Medicinal Chemistry, School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing, 210009, China
| | - Shang Li
- Jiangsu Key Laboratory of Bioactive Natural Product Research and State Key Laboratory of Natural Medicines, Department of Natural Medicinal Chemistry, School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing, 210009, China
| | - Yonglei Zhang
- Jiangsu Key Laboratory of Bioactive Natural Product Research and State Key Laboratory of Natural Medicines, Department of Natural Medicinal Chemistry, School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing, 210009, China
| | - Fucheng Yin
- Jiangsu Key Laboratory of Bioactive Natural Product Research and State Key Laboratory of Natural Medicines, Department of Natural Medicinal Chemistry, School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing, 210009, China
| | - Heng Luo
- Jiangsu Key Laboratory of Bioactive Natural Product Research and State Key Laboratory of Natural Medicines, Department of Natural Medicinal Chemistry, School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing, 210009, China
| | - Xinye Chen
- Jiangsu Key Laboratory of Bioactive Natural Product Research and State Key Laboratory of Natural Medicines, Department of Natural Medicinal Chemistry, School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing, 210009, China
| | - Ningjie Cui
- Jiangsu Key Laboratory of Bioactive Natural Product Research and State Key Laboratory of Natural Medicines, Department of Natural Medicinal Chemistry, School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing, 210009, China
| | - Siyuan Wan
- Jiangsu Key Laboratory of Bioactive Natural Product Research and State Key Laboratory of Natural Medicines, Department of Natural Medicinal Chemistry, School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing, 210009, China
| | - Xinxin Li
- Jiangsu Key Laboratory of Bioactive Natural Product Research and State Key Laboratory of Natural Medicines, Department of Natural Medicinal Chemistry, School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing, 210009, China
| | - Lingyi Kong
- Jiangsu Key Laboratory of Bioactive Natural Product Research and State Key Laboratory of Natural Medicines, Department of Natural Medicinal Chemistry, School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing, 210009, China.
| | - Xiaobing Wang
- Jiangsu Key Laboratory of Bioactive Natural Product Research and State Key Laboratory of Natural Medicines, Department of Natural Medicinal Chemistry, School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing, 210009, China.
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6
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Santillo AF, Leuzy A, Honer M, Landqvist Waldö M, Tideman P, Harper L, Ohlsson T, Moes S, Giannini L, Jögi J, Groot C, Ossenkoppele R, Strandberg O, van Swieten J, Smith R, Hansson O. [ 18F]RO948 tau positron emission tomography in genetic and sporadic frontotemporal dementia syndromes. Eur J Nucl Med Mol Imaging 2023; 50:1371-1383. [PMID: 36513817 PMCID: PMC10027632 DOI: 10.1007/s00259-022-06065-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Accepted: 11/28/2022] [Indexed: 12/15/2022]
Abstract
PURPOSE To examine [18F]RO948 retention in FTD, sampling the underlying protein pathology heterogeneity. METHODS A total of 61 individuals with FTD (n = 35), matched cases of AD (n = 13) and Aβ-negative cognitively unimpaired individuals (n = 13) underwent [18F]RO948PET and MRI. FTD included 21 behavioral variant FTD (bvFTD) cases, 11 symptomatic C9orf72 mutation carriers, one patient with non-genetic bvFTD-ALS, one individual with bvFTD due to a GRN mutation, and one due to a MAPT mutation (R406W). Tracer retention was examined using a region-of-interest and voxel-wise approaches. Two individuals (bvFTD due to C9orf72) underwent postmortem neuropathological examination. Tracer binding was additionally assessed in vitro using [3H]RO948 autoradiography in six separate cases. RESULTS [18F]RO948 retention across ROIs was clearly lower than in AD and comparable to that in Aβ-negative cognitively unimpaired individuals. Only minor loci of tracer retention were seen in bvFTD; these did not overlap with the observed cortical atrophy in the cases, the expected pattern of atrophy, nor the expected or verified protein pathology distribution. Autoradiography analyses showed no specific [3H]RO948 binding. The R406W MAPT mutation carriers were clear exceptions with AD-like retention levels and specific in-vitro binding. CONCLUSION [18F]RO948 uptake is not significantly increased in the majority of FTD patients, with a clear exception being specific MAPT mutations.
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Affiliation(s)
- Alexander F Santillo
- Department of Clinical Sciences, Clinical Memory Research Unit, Faculty of Medicine, Lund University, Lund/Malmö, Sweden.
- Memory Clinic, Skåne University Hospital, SE-20502, Malmö, Sweden.
| | - Antoine Leuzy
- Department of Clinical Sciences, Clinical Memory Research Unit, Faculty of Medicine, Lund University, Lund/Malmö, Sweden
| | - Michael Honer
- Pharma Research and Early Development, Roche Innovation Center Basel, F. Hoffmann-La Roche, Basel, Switzerland
| | - Maria Landqvist Waldö
- Clinical Sciences Helsingborg, Department of Clinical Sciences Lund, Lund University, Lund, Sweden
| | - Pontus Tideman
- Department of Clinical Sciences, Clinical Memory Research Unit, Faculty of Medicine, Lund University, Lund/Malmö, Sweden
| | - Luke Harper
- Department of Clinical Sciences, Clinical Memory Research Unit, Faculty of Medicine, Lund University, Lund/Malmö, Sweden
| | - Tomas Ohlsson
- Radiation Physics, Skane University Hospital, Scania, Sweden
| | - Svenja Moes
- Pharma Research and Early Development, Roche Innovation Center Basel, F. Hoffmann-La Roche, Basel, Switzerland
| | - Lucia Giannini
- Alzheimer Center, Department of Neurology, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Jonas Jögi
- Clinical Physiology, Department of Clinical Sciences Lund, Lund University, Lund, Sweden
| | - Colin Groot
- Department of Clinical Sciences, Clinical Memory Research Unit, Faculty of Medicine, Lund University, Lund/Malmö, Sweden
| | - Rik Ossenkoppele
- Department of Clinical Sciences, Clinical Memory Research Unit, Faculty of Medicine, Lund University, Lund/Malmö, Sweden
- Alzheimer Center Amsterdam, Department of Neurology, Amsterdam Neuroscience, Vrije Universiteit Amsterdam, Amsterdam UMC, Amsterdam, The Netherlands
| | - Olof Strandberg
- Department of Clinical Sciences, Clinical Memory Research Unit, Faculty of Medicine, Lund University, Lund/Malmö, Sweden
| | - John van Swieten
- Alzheimer Center, Department of Neurology, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Ruben Smith
- Department of Clinical Sciences, Clinical Memory Research Unit, Faculty of Medicine, Lund University, Lund/Malmö, Sweden
- Department of Neurology, Skåne University Hospital, Lund, Sweden
| | - Oskar Hansson
- Department of Clinical Sciences, Clinical Memory Research Unit, Faculty of Medicine, Lund University, Lund/Malmö, Sweden
- Memory Clinic, Skåne University Hospital, SE-20502, Malmö, Sweden
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7
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Loftus JR, Puri S, Meyers SP. Multimodality imaging of neurodegenerative disorders with a focus on multiparametric magnetic resonance and molecular imaging. Insights Imaging 2023; 14:8. [PMID: 36645560 PMCID: PMC9842851 DOI: 10.1186/s13244-022-01358-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2022] [Accepted: 12/13/2022] [Indexed: 01/17/2023] Open
Abstract
Neurodegenerative diseases afflict a large number of persons worldwide, with the prevalence and incidence of dementia rapidly increasing. Despite their prevalence, clinical diagnosis of dementia syndromes remains imperfect with limited specificity. Conventional structural-based imaging techniques also lack the accuracy necessary for confident diagnosis. Multiparametric magnetic resonance imaging and molecular imaging provide the promise of improving specificity and sensitivity in the diagnosis of neurodegenerative disease as well as therapeutic monitoring of monoclonal antibody therapy. This educational review will briefly focus on the epidemiology, clinical presentation, and pathologic findings of common and uncommon neurodegenerative diseases. Imaging features of each disease spanning from conventional magnetic resonance sequences to advanced multiparametric methods such as resting-state functional magnetic resonance imaging and arterial spin labeling imaging will be described in detail. Additionally, the review will explore the findings of each diagnosis on molecular imaging including single-photon emission computed tomography and positron emission tomography with a variety of clinically used and experimental radiotracers. The literature and clinical cases provided demonstrate the power of advanced magnetic resonance imaging and molecular techniques in the diagnosis of neurodegenerative diseases and areas of future and ongoing research. With the advent of combined positron emission tomography/magnetic resonance imaging scanners, hybrid protocols utilizing both techniques are an attractive option for improving the evaluation of neurodegenerative diseases.
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Affiliation(s)
- James Ryan Loftus
- grid.412750.50000 0004 1936 9166Department of Imaging Sciences, University of Rochester Medical Center, 601 Elmwood Ave, Rochester, NY 14642 USA
| | - Savita Puri
- grid.412750.50000 0004 1936 9166Department of Imaging Sciences, University of Rochester Medical Center, 601 Elmwood Ave, Rochester, NY 14642 USA
| | - Steven P. Meyers
- grid.412750.50000 0004 1936 9166Department of Imaging Sciences, University of Rochester Medical Center, 601 Elmwood Ave, Rochester, NY 14642 USA
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8
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Liu T, Li Y, Wang Y, Yan XX, Dai J, Cui M. Discovery and evaluation of aza-fused tricyclic derivatives for detection of Tau pathology in Alzheimer's disease. Eur J Med Chem 2023; 246:114991. [PMID: 36493618 DOI: 10.1016/j.ejmech.2022.114991] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2022] [Revised: 11/09/2022] [Accepted: 11/28/2022] [Indexed: 12/03/2022]
Abstract
For various neurodegenerative diseases, including Alzheimer's disease (AD), the abnormal aggregation of Tau is not only the predominant contributing factor but also a major biomarker for disease diagnosis. In this study, a series of aza-fused tricyclic derivatives were designed and synthesized. By changing the position and number of nitrogen atoms on the fused tricyclic core, the imidazonaphthyridine scaffold was screened and reported for the first time which could potentially detect Tau aggregates. Through a series of in vitro and in vivo biological evaluations, probe [125I]5 possessed exceptional binding affinity (IC50 = 1.63 nM) to neurofibrillary tangles in the AD brain, high selectivity over Aβ plaques (23.4-fold), clean off-target profile to monoamine oxidase A/B (MAO-A/B), and suitable pharmacokinetics (initial brain uptake = 3.22% ID/g).
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Affiliation(s)
- Tianqing Liu
- Key Laboratory of Radiopharmaceuticals, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing, 100875, China
| | - Yuying Li
- Key Laboratory of Radiopharmaceuticals, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing, 100875, China
| | - Yan Wang
- Department of Anatomy and Neurobiology, Central South University Xiangya School of Medicine, Changsha, 410013, China
| | - Xiao-Xin Yan
- Department of Anatomy and Neurobiology, Central South University Xiangya School of Medicine, Changsha, 410013, China
| | - Jiapei Dai
- Wuhan Institute for Neuroscience and Neuroengineering, South-Central Minzu University, Wuhan, 430074, China
| | - Mengchao Cui
- Key Laboratory of Radiopharmaceuticals, Ministry of Education, College of Chemistry, Beijing Normal University, Beijing, 100875, China; Center for Advanced Materials Research, Beijing Normal University, Zhuhai, 519087, China.
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9
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Edelmann MR. Radiolabelling small and biomolecules for tracking and monitoring. RSC Adv 2022; 12:32383-32400. [PMID: 36425706 PMCID: PMC9650631 DOI: 10.1039/d2ra06236d] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2022] [Accepted: 11/02/2022] [Indexed: 11/13/2022] Open
Abstract
Radiolabelling small molecules with beta-emitters has been intensively explored in the last decades and novel concepts for the introduction of radionuclides continue to be reported regularly. New catalysts that induce carbon/hydrogen activation are able to incorporate isotopes such as deuterium or tritium into small molecules. However, these established labelling approaches have limited applicability for nucleic acid-based drugs, therapeutic antibodies, or peptides, which are typical of the molecules now being investigated as novel therapeutic modalities. These target molecules are usually larger (significantly >1 kDa), mostly multiply charged, and often poorly soluble in organic solvents. However, in preclinical research they often require radiolabelling in order to track and monitor drug candidates in metabolism, biotransformation, or pharmacokinetic studies. Currently, the most established approach to introduce a tritium atom into an oligonucleotide is based on a multistep synthesis, which leads to a low specific activity with a high level of waste and high costs. The most common way of tritiating peptides is using appropriate precursors. The conjugation of a radiolabelled prosthetic compound to a functional group within a protein sequence is a commonly applied way to introduce a radionuclide or a fluorescent tag into large molecules. This review highlights the state-of-the-art in different radiolabelling approaches for oligonucleotides, peptides, and proteins, as well as a critical assessment of the impact of the label on the properties of the modified molecules. Furthermore, applications of radiolabelled antibodies in biodistribution studies of immune complexes and imaging of brain targets are reported.
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Affiliation(s)
- Martin R Edelmann
- Department of Pharmacy and Pharmacology, University of Bath Bath BA2 7AY UK
- Roche Pharma Research and Early Development, Roche Innovation Center Basel, Therapeutic Modalities, Small Molecule Research, Isotope Synthesis, F. Hoffmann-La Roche Ltd CH-4070 Basel Switzerland
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10
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Kallinen A, Kassiou M. Tracer development for PET imaging of proteinopathies. Nucl Med Biol 2022; 114-115:108-120. [PMID: 35487833 DOI: 10.1016/j.nucmedbio.2022.04.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Revised: 02/17/2022] [Accepted: 04/04/2022] [Indexed: 12/27/2022]
Abstract
This review outlines small molecule radiotracers developed for positron emission tomography (PET) imaging of proteinopathies, neurodegenerative diseases characterised by accumulation of malformed proteins, over the last two decades with the focus on radioligands that have progressed to clinical studies. Introduction provides a short summary of proteinopathy targets used for PET imaging, including vastly studied proteins Aβ and tau and emerging α-synuclein. In the main section, clinically relevant Aβ and tau radioligand classes and their properties are discussed, including an overview of lead compounds and radioligand candidates studied as α-synuclein imaging agents in the early discovery and preclinical development phase. Lastly, the specific challenges and future directions in proteinopathy radioligand development are summarized.
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Affiliation(s)
- Annukka Kallinen
- Garvan Institute of Medical Research, 384 Victoria St, NSW 2010, Australia.
| | - Michael Kassiou
- School of Chemistry, The University of Sydney, NSW 2006, Australia
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11
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Zhou J, Benoit M, Sharoar MG. Recent advances in pre-clinical diagnosis of Alzheimer's disease. Metab Brain Dis 2022; 37:1703-1725. [PMID: 33900524 DOI: 10.1007/s11011-021-00733-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/02/2021] [Accepted: 04/05/2021] [Indexed: 11/26/2022]
Abstract
Alzheimer's disease (AD) is the most common dementia with currently no known cures or disease modifying treatments (DMTs), despite much time and effort from the field. Diagnosis and intervention of AD during the early pre-symptomatic phase of the disease is thought to be a more effective strategy. Therefore, the detection of biomarkers has emerged as a critical tool for monitoring the effect of new AD therapies, as well as identifying patients most likely to respond to treatment. The establishment of the amyloid/tau/neurodegeneration (A/T/N) framework in 2018 has codified the contexts of use of AD biomarkers in neuroimaging and bodily fluids for research and diagnostic purposes. Furthermore, a renewed drive for novel AD biomarkers and innovative methods of detection has emerged with the goals of adding additional insight to disease progression and discovery of new therapeutic targets. The use of biomarkers has accelerated the development of AD drugs and will bring new therapies to patients in need. This review highlights recent methods utilized to diagnose antemortem AD.
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Affiliation(s)
- John Zhou
- Department of Neuroscience, University of Connecticut Health, Farmington, CT, 06030, USA
- Molecular Medicine Program, Cleveland Clinic Lerner College of Medicine of Case Western Reserve University, Cleveland, OH, 44195, USA
| | - Marc Benoit
- Department of Neuroscience, University of Connecticut Health, Farmington, CT, 06030, USA
| | - Md Golam Sharoar
- Department of Neuroscience, University of Connecticut Health, Farmington, CT, 06030, USA.
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12
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Li Y, Liu T, Cui M. Recent development in selective Tau tracers for PET imaging in the brain. CHINESE CHEM LETT 2022. [DOI: 10.1016/j.cclet.2022.03.024] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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13
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14
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Groot C, Villeneuve S, Smith R, Hansson O, Ossenkoppele R. Tau PET Imaging in Neurodegenerative Disorders. J Nucl Med 2022; 63:20S-26S. [PMID: 35649647 DOI: 10.2967/jnumed.121.263196] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Revised: 03/09/2022] [Indexed: 11/16/2022] Open
Abstract
The advent of PET ligands that bind tau pathology has enabled the quantification and visualization of tau pathology in aging and in Alzheimer disease (AD). There is strong evidence from neuropathologic studies that the most widely used tau PET tracers (i.e., 18F-flortaucipir, 18F-MK6240, 18F-RO948, and 18F-PI2620) bind tau aggregates formed in AD in the more advanced (i.e., ≥IV) Braak stages. However, tracer binding in most non-AD tauopathies is weaker and overlaps to a large extent with known off-target binding regions, limiting the quantification and visualization of non-AD tau pathology in vivo. Off-target binding is generally present in the substantia nigra, basal ganglia, pituitary, choroid plexus, longitudinal sinuses, meninges, or skull in a tracer-specific manner. Most cross-sectional studies use the inferior aspect of the cerebellar gray matter as a reference region, whereas for longitudinal analyses, an eroded white matter reference region is sometimes selected. No consensus has yet been reached on whether to use partial-volume correction of tau PET data. Although an increased neocortical tau PET signal is rare in cognitively unimpaired individuals, even in amyloid-β-positive cases, such a signal holds important prognostic information because preliminary data suggest that an elevated tau PET signal predicts cognitive decline over time. Also, in symptomatic stages of AD (i.e., mild cognitive impairment or AD dementia), tau PET shows great potential as a prognostic marker because an elevated baseline tau PET retention forecasts future cognitive decline and brain atrophy. For differential diagnostic use, the primary utility of tau PET is to differentiate AD dementia from other neurodegenerative diseases, as is in line with the conditions for the approval of 18F-flortaucipir by the U.S. Food and Drug Administration for clinical use. The differential diagnostic performance drops substantially at the mild-cognitive-impairment stage of AD, and there is no sufficient evidence for detection of sporadic non-AD primary tauopathies at the individual level for any of the currently available tau PET tracers. In conclusion, while the field is currently addressing outstanding methodologic issues, tau PET is gradually moving toward clinical application as a diagnostic and possibly prognostic marker in dementia expert centers and as a tool for selecting participants, assessing target engagement, and monitoring treatment effects in clinical trials.
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Affiliation(s)
- Colin Groot
- Clinical Memory Research Unit, Lund University, Lund, Sweden.,Alzheimer Center Amsterdam, Department of Neurology, Amsterdam Neuroscience, Amsterdam UMC, Location VUMC, Amsterdam, The Netherlands
| | - Sylvia Villeneuve
- Department of Psychiatry, Faculty of Medicine, McGill University, Montreal, Canada.,Douglas Mental Health University Institute, Montreal, Canada.,McConnell Brain Imaging Centre, Montreal Neurological Institute, Montreal, Canada; and
| | - Ruben Smith
- Clinical Memory Research Unit, Lund University, Lund, Sweden.,Memory Clinic, Skåne University Hospital, Malmö, Sweden
| | - Oskar Hansson
- Clinical Memory Research Unit, Lund University, Lund, Sweden.,Memory Clinic, Skåne University Hospital, Malmö, Sweden
| | - Rik Ossenkoppele
- Clinical Memory Research Unit, Lund University, Lund, Sweden; .,Alzheimer Center Amsterdam, Department of Neurology, Amsterdam Neuroscience, Amsterdam UMC, Location VUMC, Amsterdam, The Netherlands
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15
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Yousefzadeh-Nowshahr E, Winter G, Bohn P, Kneer K, von Arnim CAF, Otto M, Solbach C, Anderl-Straub S, Polivka D, Fissler P, Strobel J, Kletting P, Riepe MW, Higuchi M, Glatting G, Ludolph A, Beer AJ. Quantitative analysis of regional distribution of tau pathology with 11C-PBB3-PET in a clinical setting. PLoS One 2022; 17:e0266906. [PMID: 35404966 PMCID: PMC9045369 DOI: 10.1371/journal.pone.0266906] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Accepted: 03/29/2022] [Indexed: 12/28/2022] Open
Abstract
PURPOSE The recent developments of tau-positron emission tomography (tau-PET) enable in vivo assessment of neuropathological tau aggregates. Among the tau-specific tracers, the application of 11C-pyridinyl-butadienyl-benzothiazole 3 (11C-PBB3) in PET shows high sensitivity to Alzheimer disease (AD)-related tau deposition. The current study investigates the regional tau load in patients within the AD continuum, biomarker-negative individuals (BN) and patients with suspected non-AD pathophysiology (SNAP) using 11C-PBB3-PET. MATERIALS AND METHODS A total of 23 memory clinic outpatients with recent decline of episodic memory were examined using 11C-PBB3-PET. Pittsburg compound B (11C-PIB) PET was available for 17, 18F-flurodeoxyglucose (18F-FDG) PET for 16, and cerebrospinal fluid (CSF) protein levels for 11 patients. CSF biomarkers were considered abnormal based on Aβ42 (< 600 ng/L) and t-tau (> 450 ng/L). The PET biomarkers were classified as positive or negative using statistical parametric mapping (SPM) analysis and visual assessment. Using the amyloid/tau/neurodegeneration (A/T/N) scheme, patients were grouped as within the AD continuum, SNAP, and BN based on amyloid and neurodegeneration status. The 11C-PBB3 load detected by PET was compared among the groups using both atlas-based and voxel-wise analyses. RESULTS Seven patients were identified as within the AD continuum, 10 SNAP and 6 BN. In voxel-wise analysis, significantly higher 11C-PBB3 binding was observed in the AD continuum group compared to the BN patients in the cingulate gyrus, tempo-parieto-occipital junction and frontal lobe. Compared to the SNAP group, patients within the AD continuum had a considerably increased 11C-PBB3 uptake in the posterior cingulate cortex. There was no significant difference between SNAP and BN groups. The atlas-based analysis supported the outcome of the voxel-wise quantification analysis. CONCLUSION Our results suggest that 11C-PBB3-PET can effectively analyze regional tau load and has the potential to differentiate patients in the AD continuum group from the BN and SNAP group.
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Affiliation(s)
- Elham Yousefzadeh-Nowshahr
- Department of Nuclear Medicine, Medical Radiation Physics, Ulm
University, Ulm, Germany
- Department of Nuclear Medicine, Medical Center—University of Freiburg,
Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Gordon Winter
- Department of Nuclear Medicine, Ulm University, Ulm,
Germany
| | - Peter Bohn
- Department of Nuclear Medicine, Inselspital Bern—University of Bern,
Bern, Switzerland
| | - Katharina Kneer
- Department of Nuclear Medicine, Ulm University, Ulm,
Germany
| | - Christine A. F. von Arnim
- Department of Neurology, Ulm University, Ulm, Germany
- Department of Geriatrics, University Medical Center Göttingen, Göttingen,
Germany
| | - Markus Otto
- Department of Neurology, University Hospital Halle (Saale), Halle,
Germany
| | | | | | - Dörte Polivka
- Department of Neurology, Ulm University, Ulm, Germany
| | - Patrick Fissler
- Department of Neurology, Ulm University, Ulm, Germany
- Psychiatric Services of Thurgovia (Academic Teaching Hospital of Medical
University Salzburg), Münsterlingen, Switzerland
| | - Joachim Strobel
- Department of Nuclear Medicine, Ulm University, Ulm,
Germany
| | - Peter Kletting
- Department of Nuclear Medicine, Medical Radiation Physics, Ulm
University, Ulm, Germany
- Department of Nuclear Medicine, Ulm University, Ulm,
Germany
| | - Matthias W. Riepe
- Department of Psychiatry and Psychotherapy II, Ulm University, Ulm,
Germany
| | - Makoto Higuchi
- National Institute of Radiological Sciences, Chiba,
Japan
| | - Gerhard Glatting
- Department of Nuclear Medicine, Medical Radiation Physics, Ulm
University, Ulm, Germany
- Department of Nuclear Medicine, Ulm University, Ulm,
Germany
| | - Albert Ludolph
- Department of Neurology, Ulm University, Ulm, Germany
- German Center for Neurodegerative Diseases (DZNE), Ulm,
Germany
| | - Ambros J. Beer
- Department of Nuclear Medicine, Ulm University, Ulm,
Germany
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16
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Wang J, Takahashi K, Shoup TM, Gong L, Li Y, El Fakhri G, Zhang Z, Brownell AL. Organomediated Cleavage of Benzoyl Group Enables an Efficient Synthesis of 1- (6-Nitropyridin-2-yl)thiourea and its application for developing 18F-labeled PET Tracers. Bioorg Chem 2022; 124:105804. [DOI: 10.1016/j.bioorg.2022.105804] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2022] [Revised: 03/08/2022] [Accepted: 04/08/2022] [Indexed: 11/24/2022]
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17
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He Y, Gobbi LC, Herde AM, Rombach D, Ritter M, Kuhn B, Wittwer MB, Heer D, Hornsperger B, Bell C, O'Hara F, Benz J, Honer M, Keller C, Collin L, Richter H, Schibli R, Grether U, Mu L. Discovery, synthesis and evaluation of novel reversible monoacylglycerol lipase radioligands bearing a morpholine-3-one scaffold. Nucl Med Biol 2022; 108-109:24-32. [DOI: 10.1016/j.nucmedbio.2022.02.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Revised: 01/29/2022] [Accepted: 02/14/2022] [Indexed: 02/07/2023]
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18
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Kim JS, Son HJ, Oh M, Lee DY, Kim HW, Oh J. 60 Years of Achievements by KSNM in Neuroimaging Research. Nucl Med Mol Imaging 2022; 56:3-16. [PMID: 35186156 PMCID: PMC8828843 DOI: 10.1007/s13139-021-00727-1] [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: 07/22/2021] [Revised: 11/01/2021] [Accepted: 12/07/2021] [Indexed: 02/03/2023] Open
Abstract
Nuclear medicine neuroimaging is able to show functional and molecular biologic abnormalities in various neuropsychiatric diseases. Therefore, it has played important roles in the clinical diagnosis and in research on the normal and pathological states of the brain. More than 400 outstanding studies have been conducted by Korean researchers over the past 60 years. In the 1990s, when multiheaded single-photon emission computed tomography (SPECT) scanners were first introduced in South Korea, stroke research using brain perfusion SPECT was conducted. With the spread of positron emission tomography (PET) scanners in the 2000s, research on the clinical usefulness of PET and the evaluation of pathophysiology in various diseases such as epilepsy, brain tumors, degenerative brain diseases, and other neuropsychiatric diseases were actively conducted using [18F]FDG and various neuroreceptor tracers. In the 2010s, with the clinical application of new radiopharmaceuticals for amyloid and tau imaging, research demonstrating the clinical usefulness of PET imaging and the pathophysiology of dementia has increased rapidly. It is expected that the role of nuclear medicine will expand with the development of new radiopharmaceuticals and analysis technologies, along with the application of artificial intelligence for early and differential diagnosis, and the development of therapeutic agents for degenerative brain diseases.
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Affiliation(s)
- Jae Seung Kim
- Department of Nuclear Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Hye Joo Son
- Department of Nuclear Medicine, Dankook University College of Medicine, Cheonan, Republic of Korea
| | - Minyoung Oh
- Department of Nuclear Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Dong Yun Lee
- Department of Nuclear Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Hae Won Kim
- Department of Nuclear Medicine, Keimyung University Dongsan Hospital, Daegu, Republic of Korea
| | - Jungsu Oh
- Department of Nuclear Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
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19
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He Y, Schild M, Grether U, Benz J, Leibrock L, Heer D, Topp A, Collin L, Kuhn B, Wittwer M, Keller C, Gobbi LC, Schibli R, Mu L. Development of High Brain-Penetrant and Reversible Monoacylglycerol Lipase PET Tracers for Neuroimaging. J Med Chem 2022; 65:2191-2207. [PMID: 35089028 DOI: 10.1021/acs.jmedchem.1c01706] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Monoacylglycerol lipase (MAGL) is one of the key enzymes in the endocannabinoid system. Inhibition of MAGL has been proposed as an attractive approach for the treatment of various diseases. In this study, we designed and successfully synthesized two series of piperazinyl pyrrolidin-2-one derivatives as novel reversible MAGL inhibitors. (R)-[18F]13 was identified through the preliminary evaluation of two carbon-11-labeled racemic structures [11C]11 and [11C]16. In dynamic positron-emission tomography (PET) scans, (R)-[18F]13 showed a heterogeneous distribution and matched the MAGL expression pattern in the mouse brain. High brain uptake and brain-to-blood ratio were achieved by (R)-[18F]13 in comparison with previously reported reversible MAGL PET radiotracers. Target occupancy studies with a therapeutic MAGL inhibitor revealed a dose-dependent reduction of (R)-[18F]13 accumulation in the mouse brain. These findings indicate that (R)-[18F]13 ([18F]YH149) is a highly promising PET probe for visualizing MAGL non-invasively in vivo and holds great potential to support drug development.
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Affiliation(s)
- Yingfang He
- Center for Radiopharmaceutical Sciences, Institute of Pharmaceutical Sciences, Department of Chemistry and Applied Biosciences, ETH Zurich, CH-8093 Zurich, Switzerland
| | - Matthias Schild
- Center for Radiopharmaceutical Sciences, Institute of Pharmaceutical Sciences, Department of Chemistry and Applied Biosciences, ETH Zurich, CH-8093 Zurich, Switzerland
| | - Uwe Grether
- Pharma Research and Early Development, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd, CH-4070 Basel, Switzerland
| | - Jörg Benz
- Pharma Research and Early Development, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd, CH-4070 Basel, Switzerland
| | - Lea Leibrock
- Pharma Research and Early Development, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd, CH-4070 Basel, Switzerland
| | - Dominik Heer
- Pharma Research and Early Development, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd, CH-4070 Basel, Switzerland
| | - Andreas Topp
- Pharma Research and Early Development, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd, CH-4070 Basel, Switzerland
| | - Ludovic Collin
- Pharma Research and Early Development, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd, CH-4070 Basel, Switzerland
| | - Bernd Kuhn
- Pharma Research and Early Development, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd, CH-4070 Basel, Switzerland
| | - Matthias Wittwer
- Pharma Research and Early Development, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd, CH-4070 Basel, Switzerland
| | - Claudia Keller
- Center for Radiopharmaceutical Sciences, Institute of Pharmaceutical Sciences, Department of Chemistry and Applied Biosciences, ETH Zurich, CH-8093 Zurich, Switzerland
| | - Luca C Gobbi
- Pharma Research and Early Development, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd, CH-4070 Basel, Switzerland
| | - Roger Schibli
- Center for Radiopharmaceutical Sciences, Institute of Pharmaceutical Sciences, Department of Chemistry and Applied Biosciences, ETH Zurich, CH-8093 Zurich, Switzerland
| | - Linjing Mu
- Center for Radiopharmaceutical Sciences, Institute of Pharmaceutical Sciences, Department of Chemistry and Applied Biosciences, ETH Zurich, CH-8093 Zurich, Switzerland.,Department of Nuclear Medicine, University Hospital Zurich, CH-8091 Zurich, Switzerland
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20
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Kroth H, Oden F, Molette J, Schieferstein H, Gabellieri E, Mueller A, Berndt M, Sreenivasachary N, Serra AM, Capotosti F, Schmitt-Willich H, Hickman D, Pfeifer A, Dinkelborg L, Stephens A. PI-2620 Lead Optimization Highlights the Importance of Off-Target Assays to Develop a PET Tracer for the Detection of Pathological Aggregated Tau in Alzheimer's Disease and Other Tauopathies. J Med Chem 2021; 64:12808-12830. [PMID: 34455780 DOI: 10.1021/acs.jmedchem.1c00861] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
The first candidate PI-2014 was tested in healthy controls and subjects with Alzheimer's disease (AD). As PI-2014 displayed off-target binding to monoamine oxidase A (MAO-A), a new lead with improved binding to Tau and decreased MAO-A binding was required. For compound optimization, Tau binding assays based on both human AD brain homogenate and Tau-paired helical filaments were employed. Furthermore, two MAO-A screening assays based on (1) human-recombinant MAO-A and (2) displacement of 2-fluoro-ethyl-harmine from mouse brain homogenate were employed. Removing the N-methyl group from the tricyclic core resulted in compounds displaying improved Tau binding. For the final round of optimization, the cyclic amine substituents were replaced by pyridine derivatives. PI-2620 (2-(2-fluoropyridin-4-yl)-9H-pyrrolo[2,3-b:4,5-c']dipyridine) emerged as a best candidate displaying high Tau binding, low MAO-A binding, high brain uptake, and fast and complete brain washout. Furthermore, PI-2620 showed Tau binding on brain sections from corticobasal degeneration, progressive supranuclear palsy, and Pick's disease.
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Affiliation(s)
- Heiko Kroth
- AC Immune SA, EPFL Innovation Park, Building B, 1015 Lausanne, Switzerland
| | - Felix Oden
- Life Molecular Imaging GmbH, Tegeler Strasse 6-7, 13353 Berlin, Germany
| | - Jerome Molette
- AC Immune SA, EPFL Innovation Park, Building B, 1015 Lausanne, Switzerland
| | | | | | - Andre Mueller
- Life Molecular Imaging GmbH, Tegeler Strasse 6-7, 13353 Berlin, Germany
| | - Mathias Berndt
- Life Molecular Imaging GmbH, Tegeler Strasse 6-7, 13353 Berlin, Germany
| | | | | | | | | | - David Hickman
- AC Immune SA, EPFL Innovation Park, Building B, 1015 Lausanne, Switzerland
| | - Andrea Pfeifer
- AC Immune SA, EPFL Innovation Park, Building B, 1015 Lausanne, Switzerland
| | - Ludger Dinkelborg
- Life Molecular Imaging GmbH, Tegeler Strasse 6-7, 13353 Berlin, Germany
| | - Andrew Stephens
- Life Molecular Imaging GmbH, Tegeler Strasse 6-7, 13353 Berlin, Germany
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21
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Abstract
The use of PET imaging agents in oncology, cardiovascular disease, and neurodegenerative disease shows the power of this technique in evaluating the molecular and biological characteristics of numerous diseases. These agents provide crucial information for designing therapeutic strategies for individual patients. Novel PET tracers are in continual development and many have potential use in clinical and research settings. This article discusses the potential applications of tracers in diagnostics, the biological characteristics of diseases, the ability to provide prognostic indicators, and using this information to guide treatment strategies including monitoring treatment efficacy in real time to improve outcomes and survival.
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22
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Bischof GN, Dodich A, Boccardi M, van Eimeren T, Festari C, Barthel H, Hansson O, Nordberg A, Ossenkoppele R, Sabri O, Giovanni BFG, Garibotto V, Drzezga A. Clinical validity of second-generation tau PET tracers as biomarkers for Alzheimer's disease in the context of a structured 5-phase development framework. Eur J Nucl Med Mol Imaging 2021; 48:2110-2120. [PMID: 33590274 PMCID: PMC8175320 DOI: 10.1007/s00259-020-05156-4] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Accepted: 12/07/2020] [Indexed: 12/16/2022]
Abstract
PURPOSE In 2017, the Geneva Alzheimer's disease (AD) strategic biomarker roadmap initiative proposed a framework of the systematic validation AD biomarkers to harmonize and accelerate their development and implementation in clinical practice. Here, we use this framework to examine the translatability of the second-generation tau PET tracers into the clinical context. METHODS All available literature was systematically searched based on a set of search terms that related independently to analytic validity (phases 1-2), clinical validity (phase 3-4), and clinical utility (phase 5). The progress on each of the phases was determined based on scientific criteria applied for each phase and coded as fully, partially, preliminary achieved or not achieved at all. RESULTS The validation of the second-generation tau PET tracers has successfully passed the analytical phase 1 of the strategic biomarker roadmap. Assay definition studies showed evidence on the superiority over first-generation tau PET tracers in terms of off-target binding. Studies have partially achieved the primary aim of the analytical validity stage (phase 2), and preliminary evidence has been provided for the assessment of covariates on PET signal retention. Studies investigating of the clinical validity in phases 3, 4, and 5 are still underway. CONCLUSION The current literature provides overall preliminary evidence on the establishment of the second-generation tau PET tracers into the clinical context, thereby successfully addressing some methodological issues from the tau PET tracer of the first generation. Nevertheless, bigger cohort studies, longitudinal follow-up, and examination of diverse disease population are still needed to gauge their clinical validity.
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Affiliation(s)
- Gérard N Bischof
- Department of Nuclear Medicine, University Hospital Cologne, Cologne, Germany.
| | - Alessandra Dodich
- NIMTlab, Neuroimaging and Innovative Molecular Tracers Laboratory, University of Geneva, Geneva, Switzerland
- Center for Neurocognitive Rehabilitation (CeRiN), CIMeC, University of Trento, Trento, Italy
| | - Marina Boccardi
- German Center for Neurodegenerative Disorders (DZNE), Rostock/Greifswald, Rostock, Germany
- German Center for Neurodegenerative Disorders (DZNE), Bonn/Cologne, Germany
| | - Thilo van Eimeren
- Department of Nuclear Medicine, University Hospital Cologne, Cologne, Germany
- German Center for Neurodegenerative Disorders (DZNE), Rostock/Greifswald, Rostock, Germany
- German Center for Neurodegenerative Disorders (DZNE), Bonn/Cologne, Germany
| | - Cristina Festari
- LANE - Laboratory of Alzheimer's Neuroimaging and Epidemiology, IRCCS Istituto Centro San Giovanni di Dio Fatebenefratelli, Brescia, Italy
| | - Henryk Barthel
- Department of Nuclear Medicine, University of Leipzig, Leipzig, Germany
| | - Oskar Hansson
- Memory Clinic, Skåne University Hopsital, Malmö, Sweden
- Clinical Memory Research Unit, Department of Clinical Sciences Malmö, Lund University, Lund, Sweden
| | - Agneta Nordberg
- Division of Clinical Geriatrics, Center for Alzheimer Research, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Stockholm, Sweden
| | - Rik Ossenkoppele
- Clinical Memory Research Unit, Department of Clinical Sciences Malmö, Lund University, Lund, Sweden
- Alzheimer Center Amsterdam, Department of Neurology, Amsterdam Neuroscience, Vrije Universiteit Amsterdam, Amsterdam UMC, Amsterdam, Netherlands
| | - Osama Sabri
- Department of Nuclear Medicine, University of Leipzig, Leipzig, Germany
| | - B Frisoni G Giovanni
- NIMTlab, Neuroimaging and Innovative Molecular Tracers Laboratory, University of Geneva, Geneva, Switzerland
- Memory Center - Department of Rehabilitation and Geriatrics, Geneva University Hospitals, Geneva, Switzerland
| | - Valentina Garibotto
- NIMTlab, Neuroimaging and Innovative Molecular Tracers Laboratory, University of Geneva, Geneva, Switzerland
- Nuclear Medicine and Molecular Imaging Division, Diagnostic Department, Geneva University Hospitals, Genève, Switzerland
| | - Alexander Drzezga
- Department of Nuclear Medicine, University Hospital Cologne, Cologne, Germany
- German Center for Neurodegenerative Disorders (DZNE), Rostock/Greifswald, Rostock, Germany
- German Center for Neurodegenerative Disorders (DZNE), Bonn/Cologne, Germany
- Molecular Organization of the Brain, Institute for Neuroscience and Medicine (INM-2), Jülich, Germany
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23
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Leuzy A, Smith R, Ossenkoppele R, Santillo A, Borroni E, Klein G, Ohlsson T, Jögi J, Palmqvist S, Mattsson-Carlgren N, Strandberg O, Stomrud E, Hansson O. Diagnostic Performance of RO948 F 18 Tau Positron Emission Tomography in the Differentiation of Alzheimer Disease From Other Neurodegenerative Disorders. JAMA Neurol 2021; 77:955-965. [PMID: 32391858 PMCID: PMC7215644 DOI: 10.1001/jamaneurol.2020.0989] [Citation(s) in RCA: 113] [Impact Index Per Article: 37.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Question How does RO948 F 18 positron emission tomographic scanning discriminate between Alzheimer disease and other neurodegenerative disorders in comparison with magnetic resonance imaging and cerebrospinal fluid measures? Findings In this diagnostic study including 613 patients from the Swedish BioFINDER-2 clinical trial, standard uptake value ratios of RO948 F 18 were higher in patients with Alzheimer disease dementia compared with cognitively unimpaired controls and patients with other neurodegenerative disorders; furthermore, RO948 F 18 outperformed magnetic resonance imaging and cerebrospinal fluid measures. Generally, tau positron emission tomographic positivity was confined to amyloid β–positive cases or MAPT R406W mutation carriers in this cohort; in patients with semantic variant primary progressive aphasia, RO948 F 18 retention was lower than that for flortaucipir F 18. Meaning These findings suggest that RO948 F 18 has a high specificity for Alzheimer disease–type tau and highlight its potential as a diagnostic marker in the workup of patients treated in memory clinics. Importance The diagnostic performance of second-generation tau positron emission tomographic (PET) tracers is not yet known. Objective To examine the novel tau PET tracer RO948 F 18 ([18F]RO948) performance in discriminating Alzheimer disease (AD) from non-AD neurodegenerative disorders. Design, Setting, and Participants In this diagnostic study, 613 participants in the Swedish BioFINDER-2 study were consecutively enrolled in a prospective cross-sectional study from September 4, 2017, to August 28, 2019. Participants included 257 cognitively unimpaired controls, 154 patients with mild cognitive impairment, 100 patients with AD dementia, and 102 with non-AD neurodegenerative disorders. Evaluation included a comparison of tau PET tracer [18F]RO948 with magnetic resonance imaging (MRI) and cerebrospinal fluid and a head-to-head comparison between [18F]RO948 and flortaucipir F 18 ([18F]flortaucipir) in patients with semantic variant primary progressive aphasia (svPPA). Exposures [18F]RO948 (all patients) and [18F]flortaucipir (3 patients with svPPA) tau PET; MRI (hippocampal volume, composite temporal lobe cortical thickness, whole-brain cortical thickness) and cerebrospinal fluid measures (p-tau181 and amyloid Aβ42 and Aβ40 ratio[Aβ42/Aβ40], and Aβ42/p-tau181 ratio). Main Outcomes and Measures Standard uptake value ratios (SUVRs) in 4 predefined regions of interest (ROIs) reflecting Braak staging scheme for tau pathology and encompass I-II (entorhinal cortex), III-IV (inferior/middle temporal, fusiform gyrus, parahippocampal cortex, and amygdala), I-IV, and V-VI (widespread neocortical areas), area under the receiver operating characteristic curve (AUC) values, and subtraction images between [18F]RO948 and [18F]flortaucipir. Results Diagnostic groups among the 613 participants included cognitively unimpaired (mean [SD] age, 65.8 [12.1] years; 117 men [46%]), mild cognitive impairment (age, 70.8 [8.3] years; 82 men [53%]), AD dementia (age, 73.5 [6.7] years; 57 men [57%]), and non-AD disorders (age, 70.5 [8.6] years; 41 men [40%]). Retention of [18F]RO948 was higher in AD dementia compared with all other diagnostic groups. [18F]RO948 could distinguish patients with AD dementia from individuals without cognitive impairment and those with non-AD disorders, and the highest AUC was obtained using the I-IV ROI (AUC = 0.98; 95% CI, 0.96-0.99 for AD vs no cognitive impairment and AUC = 0.97; 95% CI, 0.95-0.99 for AD vs non-AD disorders), which outperformed MRI (highest AUC = 0.91 for AD vs no cognitive impairment using whole-brain thickness, and AUC = 0.80 for AD vs non-AD disorders using temporal lobe thickness) and cerebrospinal fluid measures (highest AUC = 0.94 for AD vs no cognitive impairment using Aβ42/p-tau181, and AUC = 0.93 for AD vs non-AD disorders using Aβ42/Aβ40). Generally, tau PET positivity using [18F]RO948 was observed only in Aβ-positive cases or in MAPT R406W mutation carriers. Retention of [18F]RO948 was not pronounced in patients with svPPA, and head-to-head comparison revealed lower temporal lobe uptake than with [18F]flortaucipir. Conclusions and Relevance In this study, elevated [18F]RO948 SUVRs were most often seen among Aβ-positive cases, which suggests that [18F]RO948 has high specificity for AD-type tau and highlights its potential as a diagnostic marker in the differential diagnosis of AD.
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Affiliation(s)
- Antoine Leuzy
- Clinical Memory Research Unit, Department of Clinical Sciences, Lund University, Malmö, Sweden
| | - Ruben Smith
- Clinical Memory Research Unit, Department of Clinical Sciences, Lund University, Malmö, Sweden.,Department of Neurology, Skåne University Hospital, Lund, Sweden
| | - Rik Ossenkoppele
- Clinical Memory Research Unit, Department of Clinical Sciences, Lund University, Malmö, Sweden.,Alzheimer Center Amsterdam, Department of Neurology, Amsterdam Neuroscience, Amsterdam University Medical Center, Amsterdam, the Netherlands
| | | | | | | | - Tomas Ohlsson
- Department of Radiation Physics, Skåne University Hospital, Lund, Sweden
| | - Jonas Jögi
- Skåne University Hospital, Department of Clinical Physiology and Nuclear Medicine, Lund, Sweden
| | - Sebastian Palmqvist
- Clinical Memory Research Unit, Department of Clinical Sciences, Lund University, Malmö, Sweden.,Department of Neurology, Skåne University Hospital, Lund, Sweden
| | - Niklas Mattsson-Carlgren
- Clinical Memory Research Unit, Department of Clinical Sciences, Lund University, Malmö, Sweden.,Department of Neurology, Skåne University Hospital, Lund, Sweden.,Wallenberg Centre for Molecular Medicine, Lund University, Lund, Sweden
| | - Olof Strandberg
- Clinical Memory Research Unit, Department of Clinical Sciences, Lund University, Malmö, Sweden
| | - Erik Stomrud
- Clinical Memory Research Unit, Department of Clinical Sciences, Lund University, Malmö, Sweden.,Memory Clinic, Skåne University Hospital, Malmö, Sweden
| | - Oskar Hansson
- Clinical Memory Research Unit, Department of Clinical Sciences, Lund University, Malmö, Sweden.,Memory Clinic, Skåne University Hospital, Malmö, Sweden
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Abstract
Alzheimer's disease (AD) is the most common cause of dementia and accounts for approximately 50% to 80% of all cases of dementia. The diagnosis of probable AD is based on clinical criteria and overlapping clinical features pose a challenge to accurate diagnosis. However, neuroimaging has been included as a biomarker in various published criteria for the diagnosis of probable AD, in the absence of a confirmatory diagnostic test during life. Advances in neuroimaging techniques and their inclusion in diagnostic and research criteria for the diagnosis of AD includes the use of positron emission tomography (PET) imaging as a biomarker in various therapeutic and prognostic studies in AD. The development and application of a range of PET tracers will allow more detailed assessment of people with AD and will improve diagnostic specificity and targeted therapy of AD. The aim of this review is to summarize current evidence on PET imaging using the non-specific tracer [18F]fluorodeoxyglucose and specific tracers that target amyloid and tau pathology in people with AD.
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Affiliation(s)
- Shailendra Mohan Tripathi
- Aberdeen Biomedical Imaging Centre, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen, UK
| | - Alison D Murray
- Aberdeen Biomedical Imaging Centre, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen, UK
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25
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Tamil Selvan S, Ravichandar R, Kanta Ghosh K, Mohan A, Mahalakshmi P, Gulyás B, Padmanabhan P. Coordination chemistry of ligands: Insights into the design of amyloid beta/tau-PET imaging probes and nanoparticles-based therapies for Alzheimer’s disease. Coord Chem Rev 2021. [DOI: 10.1016/j.ccr.2020.213659] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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26
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Watanabe H, Tarumizu Y, Kaide S, Shimizu Y, Iikuni S, Nakamoto Y, Ono M. Structure-Activity and Brain Kinetics Relationships of 18F-Labeled Benzimidazopyridine Derivatives as Tau PET Tracers. ACS Med Chem Lett 2021; 12:262-266. [PMID: 33603973 PMCID: PMC7883465 DOI: 10.1021/acsmedchemlett.0c00641] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Accepted: 01/04/2021] [Indexed: 12/29/2022] Open
Abstract
Noninvasive imaging of tau aggregates with a positron emission tomography (PET) tracer is useful for the diagnosis and staging of Alzheimer's disease (AD). Recently, we found that benzimidazopyridine (BIP) is an attractive scaffold for developing PET and single photon computed emission tomography tracers targeting tau aggregates. In this study, we designed and synthesized five novel 18F-labeled compounds with various substituted groups or atoms at the 7-position of the BIP scaffold. In in vitro autoradiographic studies, all 18F-labeled BIP derivatives selectively bound to tau aggregates deposited in AD brain sections. On the other hand, the initial brain uptake of these compounds was affected by the type of substituted group or halogen atom introduced into the 7-position of the BIP scaffold. Among these compounds, [18F]Me-BIPF showed the highest brain uptake (6.79% ID/g at 2 min postinjection) and 2 min/60 min ratio (3.59). These results suggest that appropriate introduction of the substituted group or atom into the 7-position of the BIP scaffold may be effective for developing useful tau PET tracers.
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Affiliation(s)
- Hiroyuki Watanabe
- Department
of Patho-Functional Bioanalysis, Graduate School of Pharmaceutical
Sciences, Kyoto University, 46-29 Yoshida Shimoadachi-cho, Sakyo-ku, Kyoto 606-8501, Japan
| | - Yuta Tarumizu
- Department
of Patho-Functional Bioanalysis, Graduate School of Pharmaceutical
Sciences, Kyoto University, 46-29 Yoshida Shimoadachi-cho, Sakyo-ku, Kyoto 606-8501, Japan
| | - Sho Kaide
- Department
of Patho-Functional Bioanalysis, Graduate School of Pharmaceutical
Sciences, Kyoto University, 46-29 Yoshida Shimoadachi-cho, Sakyo-ku, Kyoto 606-8501, Japan
| | - Yoichi Shimizu
- Department
of Patho-Functional Bioanalysis, Graduate School of Pharmaceutical
Sciences, Kyoto University, 46-29 Yoshida Shimoadachi-cho, Sakyo-ku, Kyoto 606-8501, Japan
- Department
of Diagnostic Imaging and Nuclear Medicine, Graduate School of Medicine, Kyoto University, 54 Shogoin Kawahara-cho, Sakyo-ku, Kyoto 606-8507, Japan
| | - Shimpei Iikuni
- Department
of Patho-Functional Bioanalysis, Graduate School of Pharmaceutical
Sciences, Kyoto University, 46-29 Yoshida Shimoadachi-cho, Sakyo-ku, Kyoto 606-8501, Japan
| | - Yuji Nakamoto
- Department
of Diagnostic Imaging and Nuclear Medicine, Graduate School of Medicine, Kyoto University, 54 Shogoin Kawahara-cho, Sakyo-ku, Kyoto 606-8507, Japan
| | - Masahiro Ono
- Department
of Patho-Functional Bioanalysis, Graduate School of Pharmaceutical
Sciences, Kyoto University, 46-29 Yoshida Shimoadachi-cho, Sakyo-ku, Kyoto 606-8501, Japan
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27
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Goud NS, Bhattacharya A, Joshi RK, Nagaraj C, Bharath RD, Kumar P. Carbon-11: Radiochemistry and Target-Based PET Molecular Imaging Applications in Oncology, Cardiology, and Neurology. J Med Chem 2021; 64:1223-1259. [PMID: 33499603 DOI: 10.1021/acs.jmedchem.0c01053] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The positron emission tomography (PET) molecular imaging technique has gained its universal value as a remarkable tool for medical diagnosis and biomedical research. Carbon-11 is one of the promising radiotracers that can report target-specific information related to its pharmacology and physiology to understand the disease status. Currently, many of the available carbon-11 (t1/2 = 20.4 min) PET radiotracers are heterocyclic derivatives that have been synthesized using carbon-11 inserted different functional groups obtained from primary and secondary carbon-11 precursors. A spectrum of carbon-11 PET radiotracers has been developed against many of the upregulated and emerging targets for the diagnosis, prognosis, prediction, and therapy in the fields of oncology, cardiology, and neurology. This review focuses on the carbon-11 radiochemistry and various target-specific PET molecular imaging agents used in tumor, heart, brain, and neuroinflammatory disease imaging along with its associated pathology.
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Affiliation(s)
- Nerella Sridhar Goud
- Department of Neuroimaging and Interventional Radiology (NIIR), National Institute of Mental Health and Neuro Sciences (NIMHANS), Bengaluru 560 029, India
| | - Ahana Bhattacharya
- Department of Neuroimaging and Interventional Radiology (NIIR), National Institute of Mental Health and Neuro Sciences (NIMHANS), Bengaluru 560 029, India
| | - Raman Kumar Joshi
- Department of Neuroimaging and Interventional Radiology (NIIR), National Institute of Mental Health and Neuro Sciences (NIMHANS), Bengaluru 560 029, India
| | - Chandana Nagaraj
- Department of Neuroimaging and Interventional Radiology (NIIR), National Institute of Mental Health and Neuro Sciences (NIMHANS), Bengaluru 560 029, India
| | - Rose Dawn Bharath
- Department of Neuroimaging and Interventional Radiology (NIIR), National Institute of Mental Health and Neuro Sciences (NIMHANS), Bengaluru 560 029, India
| | - Pardeep Kumar
- Department of Neuroimaging and Interventional Radiology (NIIR), National Institute of Mental Health and Neuro Sciences (NIMHANS), Bengaluru 560 029, India
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28
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Abstract
This article presents an overview of imaging agents for PET that have been applied for research and diagnostic purposes in patients affected by dementia. Classified by the target which the agents visualize, seven groups of tracers can be distinguished, namely radiopharmaceuticals for: (1) Misfolded proteins (ß-amyloid, tau, α-synuclein), (2) Neuroinflammation (overexpression of translocator protein), (3) Elements of the cholinergic system, (4) Elements of monoamine neurotransmitter systems, (5) Synaptic density, (6) Cerebral energy metabolism (glucose transport/ hexokinase), and (7) Various other proteins. This last category contains proteins involved in mechanisms underlying neuroinflammation or cognitive impairment, which may also be potential therapeutic targets. Many receptors belong to this category: AMPA, cannabinoid, colony stimulating factor 1, metabotropic glutamate receptor 1 and 5 (mGluR1, mGluR5), opioid (kappa, mu), purinergic (P2X7, P2Y12), sigma-1, sigma-2, receptor for advanced glycation endproducts, and triggering receptor expressed on myeloid cells-1, besides several enzymes: cyclooxygenase-1 and 2 (COX-1, COX-2), phosphodiesterase-5 and 10 (PDE5, PDE10), and tropomyosin receptor kinase. Significant advances in neuroimaging have been made in the last 15 years. The use of 2-[18F]-fluoro-2-deoxy-D-glucose (FDG) for quantification of regional cerebral glucose metabolism is well-established. Three tracers for ß-amyloid plaques have been approved by the Food and Drug Administration and European Medicines Agency. Several tracers for tau neurofibrillary tangles are already applied in clinical research. Since many novel agents are in the preclinical or experimental stage of development, further advances in nuclear medicine imaging can be expected in the near future. PET studies with established tracers and tracers for novel targets may result in early diagnosis and better classification of neurodegenerative disorders and in accurate monitoring of therapy trials which involve these targets. PET data have prognostic value and may be used to assess the response of the human brain to interventions, or to select the appropriate treatment strategy for an individual patient.
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Affiliation(s)
- Aren van Waarde
- University of Groningen, University Medical Center Groningen, Department of Nuclear Medicine and Molecular Imaging, Groningen, the Netherlands.
| | - Sofia Marcolini
- University of Groningen, University Medical Center Groningen, Department of Neurology, Groningen, the Netherlands
| | - Peter Paul de Deyn
- University of Groningen, University Medical Center Groningen, Department of Neurology, Groningen, the Netherlands; University of Antwerp, Born-Bunge Institute, Neurochemistry and Behavior, Campus Drie Eiken, Wilrijk, Belgium
| | - Rudi A J O Dierckx
- University of Groningen, University Medical Center Groningen, Department of Nuclear Medicine and Molecular Imaging, Groningen, the Netherlands; Ghent University, Ghent, Belgium
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29
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Zhou K, Yang F, Li Y, Chen Y, Zhang X, Zhang J, Wang J, Dai J, Cai L, Cui M. Synthesis and Evaluation of Fluorine-18 Labeled 2-Phenylquinoxaline Derivatives as Potential Tau Imaging Agents. Mol Pharm 2021; 18:1176-1195. [PMID: 33475377 DOI: 10.1021/acs.molpharmaceut.0c01078] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
In this study, three pairs of optically pure 18F-labeled 2-phenylquinoxaline derivatives were evaluated as Tau imaging agents for the diagnosis of Alzheimer's disease (AD). The chiral 2-fluoromethyl-1,2-ethylenediol side chain was attached to the 2-phenylquinoxaline backbone to increase hydrophilicity, thereby improving the binding affinity of the probe to tangles and their selectivity toward Tau tangles over β-amyloid plaques (Aβ). These probes displayed excellent fluorescent properties and high selectivity for tangles on brain sections from transgenic mice (rTg4510) and AD patients. Quantitative binding assays with AD homogenates showed that the probes (R)-5 and (S)-16 have a high affinity (Ki = 4.1 and 10.3 nM, respectively) and high selectivity (30.5-fold and 34.6-fold, respectively) for tangles over Aβ. The high affinity and selectivity of (R)-[18F]5 and (S)-[18F]16 for tangles were further confirmed with autoradiography on AD brain tissue in vitro. In addition, they displayed sufficient blood-brain barrier penetration (7.06% and 10.95% ID/g, respectively) and suitable brain kinetics (brain2 min/brain60 min = 10.1, 6.5 respectively) in normal mice. Ex vivo metabolism studies and micro-positron emission computed tomography (PET) revealed high brain biostability, good brain kinetic properties, and low nonspecific binding for (S)-[18F]16. Together, these results demonstrate that (R)-[18F]5 and (S)-[18F]16 are promising PET probes for Tau tangles imaging.
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Affiliation(s)
- Kaixiang Zhou
- Key Laboratory of Radiopharmaceuticals, Ministry of Education, Beijing Normal University, Beijing 100875, China
| | - Fan Yang
- Key Laboratory of Radiopharmaceuticals, Ministry of Education, Beijing Normal University, Beijing 100875, China
| | - Yuying Li
- Key Laboratory of Radiopharmaceuticals, Ministry of Education, Beijing Normal University, Beijing 100875, China
| | - Yimin Chen
- Key Laboratory of Radiopharmaceuticals, Ministry of Education, Beijing Normal University, Beijing 100875, China
| | - Xiaojun Zhang
- Department of Nuclear Medicine, Chinese PLA General Hospital, Beijing 100853, China
| | - Jinming Zhang
- Department of Nuclear Medicine, Chinese PLA General Hospital, Beijing 100853, China
| | - Junfeng Wang
- Gordon Center for Medical Imaging, Department of Radiology, Massachusetts General Hospital/Harvard Medical School, Charlestown 02129, Massachusetts, United States
| | - Jiapei Dai
- Wuhan Institute for Neuroscience and Neuroengineering, South-Central University for Nationalities, Wuhan 430074, China
| | - Lisheng Cai
- Molecular Imaging Branch, National Institute of Mental Health, National Institutes of Health, Bethesda 20892, Maryland, United States
| | - Mengchao Cui
- Key Laboratory of Radiopharmaceuticals, Ministry of Education, Beijing Normal University, Beijing 100875, China
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30
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Villemagne VL, Barkhof F, Garibotto V, Landau SM, Nordberg A, van Berckel BNM. Molecular Imaging Approaches in Dementia. Radiology 2021; 298:517-530. [PMID: 33464184 DOI: 10.1148/radiol.2020200028] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The increasing prevalence of dementia worldwide places a high demand on healthcare providers to perform a diagnostic work-up in relatively early stages of the disease, given that the pathologic process usually begins decades before symptoms are evident. Structural imaging is recommended to rule out other disorders and can only provide diagnosis in a late stage with limited specificity. Where PET imaging previously focused on the spatial pattern of hypometabolism, the past decade has seen the development of novel tracers to demonstrate characteristic protein abnormalities. Molecular imaging using PET/SPECT is able to show amyloid and tau deposition in Alzheimer disease and dopamine depletion in parkinsonian disorders starting decades before symptom onset. Novel tracers for neuroinflammation and synaptic density are being developed to further unravel the molecular pathologic characteristics of dementia disorders. In this article, the authors review the current status of established and emerging PET tracers in a diagnostic setting and also their value as prognostic markers in research studies and outcome measures for clinical trials in Alzheimer disease.
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Affiliation(s)
- Victor L Villemagne
- From the Department of Psychiatry, University of Pittsburgh, Pittsburgh, Pa (V.L.V.); Department of Medicine, the University of Melbourne, Melbourne, Australia (V.L.V.); Department of Radiology and Nuclear Medicine, Amsterdam University Medical Centers, VU University Medical Center, Amsterdam, the Netherlands (F.B., B.N.M.v.B.); UCL institutes of Neurology and Healthcare Engineering, London, England (F.B.); Division of Nuclear Medicine and Molecular Imaging, Geneva University Hospitals and Laboratory of Neuroimaging and Innovative Molecular Tracers, Geneva University, Geneva, Switzerland (V.G.); Helen Wills Neuroscience Institute, University of California, Berkeley, Calif (S.M.L.); Molecular Biophysics and Integrated Bioimaging, Lawrence Berkeley National Laboratory, Berkeley, Calif (S.M.L.); Department of Neurobiology, Care Sciences and Society, Center for Alzheimer Research, Karolinska Institutet, Stockholm, Sweden (A.N.); and Theme Aging, Karolinska University Hospital, Stockholm, Sweden (A.N.)
| | - Frederik Barkhof
- From the Department of Psychiatry, University of Pittsburgh, Pittsburgh, Pa (V.L.V.); Department of Medicine, the University of Melbourne, Melbourne, Australia (V.L.V.); Department of Radiology and Nuclear Medicine, Amsterdam University Medical Centers, VU University Medical Center, Amsterdam, the Netherlands (F.B., B.N.M.v.B.); UCL institutes of Neurology and Healthcare Engineering, London, England (F.B.); Division of Nuclear Medicine and Molecular Imaging, Geneva University Hospitals and Laboratory of Neuroimaging and Innovative Molecular Tracers, Geneva University, Geneva, Switzerland (V.G.); Helen Wills Neuroscience Institute, University of California, Berkeley, Calif (S.M.L.); Molecular Biophysics and Integrated Bioimaging, Lawrence Berkeley National Laboratory, Berkeley, Calif (S.M.L.); Department of Neurobiology, Care Sciences and Society, Center for Alzheimer Research, Karolinska Institutet, Stockholm, Sweden (A.N.); and Theme Aging, Karolinska University Hospital, Stockholm, Sweden (A.N.)
| | - Valentina Garibotto
- From the Department of Psychiatry, University of Pittsburgh, Pittsburgh, Pa (V.L.V.); Department of Medicine, the University of Melbourne, Melbourne, Australia (V.L.V.); Department of Radiology and Nuclear Medicine, Amsterdam University Medical Centers, VU University Medical Center, Amsterdam, the Netherlands (F.B., B.N.M.v.B.); UCL institutes of Neurology and Healthcare Engineering, London, England (F.B.); Division of Nuclear Medicine and Molecular Imaging, Geneva University Hospitals and Laboratory of Neuroimaging and Innovative Molecular Tracers, Geneva University, Geneva, Switzerland (V.G.); Helen Wills Neuroscience Institute, University of California, Berkeley, Calif (S.M.L.); Molecular Biophysics and Integrated Bioimaging, Lawrence Berkeley National Laboratory, Berkeley, Calif (S.M.L.); Department of Neurobiology, Care Sciences and Society, Center for Alzheimer Research, Karolinska Institutet, Stockholm, Sweden (A.N.); and Theme Aging, Karolinska University Hospital, Stockholm, Sweden (A.N.)
| | - Susan M Landau
- From the Department of Psychiatry, University of Pittsburgh, Pittsburgh, Pa (V.L.V.); Department of Medicine, the University of Melbourne, Melbourne, Australia (V.L.V.); Department of Radiology and Nuclear Medicine, Amsterdam University Medical Centers, VU University Medical Center, Amsterdam, the Netherlands (F.B., B.N.M.v.B.); UCL institutes of Neurology and Healthcare Engineering, London, England (F.B.); Division of Nuclear Medicine and Molecular Imaging, Geneva University Hospitals and Laboratory of Neuroimaging and Innovative Molecular Tracers, Geneva University, Geneva, Switzerland (V.G.); Helen Wills Neuroscience Institute, University of California, Berkeley, Calif (S.M.L.); Molecular Biophysics and Integrated Bioimaging, Lawrence Berkeley National Laboratory, Berkeley, Calif (S.M.L.); Department of Neurobiology, Care Sciences and Society, Center for Alzheimer Research, Karolinska Institutet, Stockholm, Sweden (A.N.); and Theme Aging, Karolinska University Hospital, Stockholm, Sweden (A.N.)
| | - Agneta Nordberg
- From the Department of Psychiatry, University of Pittsburgh, Pittsburgh, Pa (V.L.V.); Department of Medicine, the University of Melbourne, Melbourne, Australia (V.L.V.); Department of Radiology and Nuclear Medicine, Amsterdam University Medical Centers, VU University Medical Center, Amsterdam, the Netherlands (F.B., B.N.M.v.B.); UCL institutes of Neurology and Healthcare Engineering, London, England (F.B.); Division of Nuclear Medicine and Molecular Imaging, Geneva University Hospitals and Laboratory of Neuroimaging and Innovative Molecular Tracers, Geneva University, Geneva, Switzerland (V.G.); Helen Wills Neuroscience Institute, University of California, Berkeley, Calif (S.M.L.); Molecular Biophysics and Integrated Bioimaging, Lawrence Berkeley National Laboratory, Berkeley, Calif (S.M.L.); Department of Neurobiology, Care Sciences and Society, Center for Alzheimer Research, Karolinska Institutet, Stockholm, Sweden (A.N.); and Theme Aging, Karolinska University Hospital, Stockholm, Sweden (A.N.)
| | - Bart N M van Berckel
- From the Department of Psychiatry, University of Pittsburgh, Pittsburgh, Pa (V.L.V.); Department of Medicine, the University of Melbourne, Melbourne, Australia (V.L.V.); Department of Radiology and Nuclear Medicine, Amsterdam University Medical Centers, VU University Medical Center, Amsterdam, the Netherlands (F.B., B.N.M.v.B.); UCL institutes of Neurology and Healthcare Engineering, London, England (F.B.); Division of Nuclear Medicine and Molecular Imaging, Geneva University Hospitals and Laboratory of Neuroimaging and Innovative Molecular Tracers, Geneva University, Geneva, Switzerland (V.G.); Helen Wills Neuroscience Institute, University of California, Berkeley, Calif (S.M.L.); Molecular Biophysics and Integrated Bioimaging, Lawrence Berkeley National Laboratory, Berkeley, Calif (S.M.L.); Department of Neurobiology, Care Sciences and Society, Center for Alzheimer Research, Karolinska Institutet, Stockholm, Sweden (A.N.); and Theme Aging, Karolinska University Hospital, Stockholm, Sweden (A.N.)
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Pick's Tau Fibril Shows Multiple Distinct PET Probe Binding Sites: Insights from Computational Modelling. Int J Mol Sci 2020; 22:ijms22010349. [PMID: 33396273 PMCID: PMC7796283 DOI: 10.3390/ijms22010349] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Revised: 12/27/2020] [Accepted: 12/27/2020] [Indexed: 01/08/2023] Open
Abstract
In recent years, it has been realized that the tau protein is a key player in multiple neurodegenerative diseases. Positron emission tomography (PET) radiotracers that bind to tau filaments in Alzheimer’s disease (AD) are in common use, but PET tracers binding to tau filaments of rarer, age-related dementias, such as Pick’s disease, have not been widely explored. To design disease-specific and tau-selective PET tracers, it is important to determine where and how PET tracers bind to tau filaments. In this paper, we present the first molecular modelling study on PET probe binding to the structured core of tau filaments from a patient with Pick’s disease (TauPiD). We have used docking, molecular dynamics simulations, binding-affinity and tunnel calculations to explore TauPiD binding sites, binding modes, and binding energies of PET probes (AV-1451, MK-6240, PBB3, PM-PBB3, THK-5351 and PiB) with TauPiD. The probes bind to TauPiD at multiple surface binding sites as well as in a cavity binding site. The probes show unique surface binding patterns, and, out of them all, PM-PBB3 proves to bind the strongest. The findings suggest that our computational workflow of structural and dynamic details of the tau filaments has potential for the rational design of TauPiD specific PET tracers.
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Novel PET Biomarkers to Disentangle Molecular Pathways across Age-Related Neurodegenerative Diseases. Cells 2020; 9:cells9122581. [PMID: 33276490 PMCID: PMC7761606 DOI: 10.3390/cells9122581] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Revised: 11/25/2020] [Accepted: 11/28/2020] [Indexed: 12/11/2022] Open
Abstract
There is a need to disentangle the etiological puzzle of age-related neurodegenerative diseases, whose clinical phenotypes arise from known, and as yet unknown, pathways that can act distinctly or in concert. Enhanced sub-phenotyping and the identification of in vivo biomarker-driven signature profiles could improve the stratification of patients into clinical trials and, potentially, help to drive the treatment landscape towards the precision medicine paradigm. The rapidly growing field of neuroimaging offers valuable tools to investigate disease pathophysiology and molecular pathways in humans, with the potential to capture the whole disease course starting from preclinical stages. Positron emission tomography (PET) combines the advantages of a versatile imaging technique with the ability to quantify, to nanomolar sensitivity, molecular targets in vivo. This review will discuss current research and available imaging biomarkers evaluating dysregulation of the main molecular pathways across age-related neurodegenerative diseases. The molecular pathways focused on in this review involve mitochondrial dysfunction and energy dysregulation; neuroinflammation; protein misfolding; aggregation and the concepts of pathobiology, synaptic dysfunction, neurotransmitter dysregulation and dysfunction of the glymphatic system. The use of PET imaging to dissect these molecular pathways and the potential to aid sub-phenotyping will be discussed, with a focus on novel PET biomarkers.
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Kim H, Choe YS. High-yield synthesis of a tau PET radioligand and its nonradioactive ligand using an alternative protection and deprotection strategy. J Labelled Comp Radiopharm 2020; 64:150-158. [PMID: 33125755 DOI: 10.1002/jlcr.3894] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2020] [Revised: 10/22/2020] [Accepted: 10/22/2020] [Indexed: 11/07/2022]
Abstract
Recently developed tau imaging radiopharmaceuticals show specific uptake in tau protein-rich regions in human brains without off-target binding. These radiopharmaceuticals and their nonradioactive reference ligands are generally obtained in low (radio)chemical yields. In the present study, we investigated high-yield synthesis of 18 F-RO948 ([18 F]1) and its nonradioactive ligand (1). The ligand 1 was synthesized by a Suzuki-Miyaura coupling reaction between 9-(4-methoxybenzyl)-9H-pyrrolo[2,3-b:4,5-c']dipyridin-2-yl trifluoromethanesulfonate (3) and 2-fluoro-5-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)pyridine (4), followed by oxidative removal of the para-methoxybenzyl (PMB) group with ceric ammonium nitrate (CAN). This two-step reaction gave 1 in 55.8% yield. The precursor for [18 F]1 was synthesized from 3 and 2-nitro-5-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)pyridine (6). The resulting PMB-protected precursor 8 was obtained in 74.5% yield. [18 F]1 was synthesized by radiofluorination of 8 (radiochemical conversion (RCC): 95.7 ± 1.7%), followed by deprotection of the PMB group with CAN. This one-pot, two-step radiochemical synthesis followed by HPLC purification gave [18 F]1 in high decay-corrected radiochemical yield (54-60%). The RCC of [18 F]fluoride to [18 F]1 in our two-step synthesis method was similar to that in a one-step radiofluorination reaction of a tert-butoxycarbonyl (BOC)-protected precursor 10 that proceeds with concomitant thermal deprotection of the BOC group. Taken together, the results of this study suggest that this high-yield synthesis method is useful for the synthesis of 18 F-labeled (NH)heteroarene compounds.
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Affiliation(s)
- Hyunjung Kim
- Department of Nuclear Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea
| | - Yearn Seong Choe
- Department of Nuclear Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea
- Department of Health Sciences and Technology, SAIHST, Sungkyunkwan University, Seoul, South Korea
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Synthesis and evaluation of 2-pyrrolopyridinylquinoline derivatives as selective tau PET tracers for the diagnosis of Alzheimer's disease. Nucl Med Biol 2020; 93:11-18. [PMID: 33221641 DOI: 10.1016/j.nucmedbio.2020.10.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Revised: 09/22/2020] [Accepted: 10/17/2020] [Indexed: 11/21/2022]
Abstract
INTRODUCTION [18F]THK-5351 was originally developed as a positron emission tomography (PET) imaging tracer for the detection of accumulated tau proteins, the pathological hallmark of Alzheimer's disease (AD). However, clinical studies of [18F]THK-5351 revealed the existence of off-target binding to monoamine oxidase-B (MAO-B). To overcome this off-target binding, in this work, we synthesized and evaluated 2-pyrrolopyridinylquinoline (PPQ) derivatives as selective tau PET imaging tracers. METHODS The core structure of PPQ derivatives was synthesized mainly using the Buchwald-Hartwig amination coupling reaction. All derivatives were evaluated for binding affinity towards tau and MAO-B by in vitro competitive binding assay. Radiosynthesis of PPQ derivatives was performed by 18F-radiolabeling of their tosylate precursors with activated [18F]KF/Kryptofix222 complex in dimethylsulfoxide by heating at 110 °C for 10 min. The biological properties of these [18F]PPQ derivatives were characterized by in vitro autoradiography of postmortem AD brain sections and by assay of ex vivo biodistribution in mice. RESULTS The PPQ derivatives were synthesized, with yields of 49-84%. In vitro competitive binding assay revealed that two novel PPQ derivatives-PPQ8 and PPQ9-demonstrated high binding affinity for tau (IC50 = 4.9 and 6.9 nM, respectively). The radiosynthesis of [18F]PPQ8 and [18F]PPQ9 yielded 1.4% and 50.1% isolated non-decay corrected radiochemical yield, respectively, with >99% radiochemical purity. The molar radioactivities of [18F]PPQ8 and [18F]PPQ9 were 16.9 and 64.8 GBq/μmol, respectively. The in vitro and ex vivo biological characterization of [18F]PPQ8 and [18F]PPQ9 revealed that these tracers were selective for tau in AD brain sections without off-target binding, and they furthermore demonstrated brain uptake in normal mice. CONCLUSIONS 18F-labeled PPQ derivatives improved binding affinity and selectivity for tau aggregates in AD. Further structural optimization to improve pharmacokinetics for potent tau PET imaging tracers is required.
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Yeo SK, Shepelytskyi Y, Grynko V, Albert MS. Molecular Imaging of Fluorinated Probes for Tau Protein and Amyloid-β Detection. Molecules 2020; 25:molecules25153413. [PMID: 32731418 PMCID: PMC7435578 DOI: 10.3390/molecules25153413] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Revised: 07/24/2020] [Accepted: 07/24/2020] [Indexed: 12/16/2022] Open
Abstract
Alzheimer’s disease (AD) is the most common form of dementia and results in progressive neurodegeneration. The incidence rate of AD is increasing, creating a major public health issue. AD is characterized by neurofibrillary tangles (NFTs) composed of hyperphosphorylated tau protein and senile plaques composed of amyloid-β (Aβ). Currently, a definitive diagnosis of AD is accomplished post-mortem. Thus, the use of molecular probes that are able to selectively bind to NFTs or Aβ can be valuable tools for the accurate and early diagnosis of AD. The aim of this review is to summarize and highlight fluorinated molecular probes that can be used for molecular imaging to detect either NFTs or Aβ. Specifically, fluorinated molecular probes used in conjunction with 19F MRI, PET, and fluorescence imaging will be explored.
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Affiliation(s)
- Sarah K. Yeo
- Biology Department, Lakehead University, Thunder Bay, ON P7B 5E1, Canada;
| | - Yurii Shepelytskyi
- Chemistry and Materials Science Program, Lakehead University, Thunder Bay, ON P7B 5E1, Canada; (Y.S.); (V.G.)
- Thunder Bay Regional Health Research Institute, Thunder Bay, ON P7B 6V4, Canada
| | - Vira Grynko
- Chemistry and Materials Science Program, Lakehead University, Thunder Bay, ON P7B 5E1, Canada; (Y.S.); (V.G.)
- Thunder Bay Regional Health Research Institute, Thunder Bay, ON P7B 6V4, Canada
| | - Mitchell S. Albert
- Thunder Bay Regional Health Research Institute, Thunder Bay, ON P7B 6V4, Canada
- Chemistry Department, Lakehead University, Thunder Bay, ON P7B 5E1, Canada
- Northern Ontario School of Medicine, Thunder Bay, ON P7B 5E1, Canada
- Correspondence: ; Tel.: +1-807-355-9191
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Young PNE, Estarellas M, Coomans E, Srikrishna M, Beaumont H, Maass A, Venkataraman AV, Lissaman R, Jiménez D, Betts MJ, McGlinchey E, Berron D, O'Connor A, Fox NC, Pereira JB, Jagust W, Carter SF, Paterson RW, Schöll M. Imaging biomarkers in neurodegeneration: current and future practices. Alzheimers Res Ther 2020; 12:49. [PMID: 32340618 PMCID: PMC7187531 DOI: 10.1186/s13195-020-00612-7] [Citation(s) in RCA: 79] [Impact Index Per Article: 19.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2019] [Accepted: 04/01/2020] [Indexed: 12/12/2022]
Abstract
There is an increasing role for biological markers (biomarkers) in the understanding and diagnosis of neurodegenerative disorders. The application of imaging biomarkers specifically for the in vivo investigation of neurodegenerative disorders has increased substantially over the past decades and continues to provide further benefits both to the diagnosis and understanding of these diseases. This review forms part of a series of articles which stem from the University College London/University of Gothenburg course "Biomarkers in neurodegenerative diseases". In this review, we focus on neuroimaging, specifically positron emission tomography (PET) and magnetic resonance imaging (MRI), giving an overview of the current established practices clinically and in research as well as new techniques being developed. We will also discuss the use of machine learning (ML) techniques within these fields to provide additional insights to early diagnosis and multimodal analysis.
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Affiliation(s)
- Peter N E Young
- Wallenberg Centre for Molecular and Translational Medicine and the Department of Psychiatry and Neurochemistry, University of Gothenburg, Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Mar Estarellas
- Centre for Medical Image Computing (CMIC), Department of Computer Science & Department of Medical Physics and Biomedical Engineering, University College London, London, UK
| | - Emma Coomans
- Department of Radiology and Nuclear Medicine, Amsterdam Neuroscience, Vrije Universiteit Amsterdam, Amsterdam UMC, Amsterdam, Netherlands
| | - Meera Srikrishna
- Wallenberg Centre for Molecular and Translational Medicine and the Department of Psychiatry and Neurochemistry, University of Gothenburg, Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Helen Beaumont
- Neuroscience and Aphasia Research Unit, Division of Neuroscience and Experimental Psychology, The University of Manchester, Manchester, UK
| | - Anne Maass
- German Center for Neurodegenerative Diseases (DZNE), Magdeburg, Germany
| | - Ashwin V Venkataraman
- Division of Brain Sciences, Imperial College London, London, UK
- United Kingdom Dementia Research Institute, Imperial College London, London, UK
| | - Rikki Lissaman
- Cardiff University Brain Research Imaging Centre (CUBRIC), School of Psychology, Cardiff, UK
| | - Daniel Jiménez
- Dementia Research Centre, UCL Institute of Neurology, University College London, London, UK
- Department of Neurological Sciences, Faculty of Medicine, University of Chile, Santiago, Chile
| | - Matthew J Betts
- German Center for Neurodegenerative Diseases (DZNE), Magdeburg, Germany
- Institute of Cognitive Neurology and Dementia Research, Otto-von-Guericke-University Magdeburg, Magdeburg, Germany
| | | | - David Berron
- Clinical Memory Research Unit, Department of Clinical Sciences Malmö, Lund University, Lund, Sweden
| | - Antoinette O'Connor
- Dementia Research Centre, UCL Institute of Neurology, University College London, London, UK
| | - Nick C Fox
- Dementia Research Centre, UCL Institute of Neurology, University College London, London, UK
| | - Joana B Pereira
- Clinical Memory Research Unit, Department of Clinical Sciences Malmö, Lund University, Lund, Sweden
- Division of Clinical Geriatrics, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Stockholm, Sweden
| | - William Jagust
- Helen Wills Neuroscience Institute, University of California, Berkeley, USA
- Molecular Biophysics and Integrated Bioimaging, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Stephen F Carter
- Department of Psychiatry, School of Clinical Medicine, University of Cambridge, Cambridge, UK
- Wolfson Molecular Imaging Centre, Division of Neuroscience and Experimental Psychology, MAHSC, University of Manchester, Manchester, UK
| | - Ross W Paterson
- Dementia Research Centre, UCL Institute of Neurology, University College London, London, UK
| | - Michael Schöll
- Wallenberg Centre for Molecular and Translational Medicine and the Department of Psychiatry and Neurochemistry, University of Gothenburg, Sahlgrenska University Hospital, Gothenburg, Sweden.
- Dementia Research Centre, UCL Institute of Neurology, University College London, London, UK.
- Department of Clinical Physiology, Sahlgrenska University Hospital, Gothenburg, Sweden.
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Uzuegbunam BC, Librizzi D, Hooshyar Yousefi B. PET Radiopharmaceuticals for Alzheimer's Disease and Parkinson's Disease Diagnosis, the Current and Future Landscape. Molecules 2020; 25:E977. [PMID: 32098280 PMCID: PMC7070523 DOI: 10.3390/molecules25040977] [Citation(s) in RCA: 56] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2020] [Revised: 02/17/2020] [Accepted: 02/17/2020] [Indexed: 02/06/2023] Open
Abstract
Ironically, population aging which is considered a public health success has been accompanied by a myriad of new health challenges, which include neurodegenerative disorders (NDDs), the incidence of which increases proportionally to age. Among them, Alzheimer's disease (AD) and Parkinson's disease (PD) are the most common, with the misfolding and the aggregation of proteins being common and causal in the pathogenesis of both diseases. AD is characterized by the presence of hyperphosphorylated τ protein (tau), which is the main component of neurofibrillary tangles (NFTs), and senile plaques the main component of which is β-amyloid peptide aggregates (Aβ). The neuropathological hallmark of PD is α-synuclein aggregates (α-syn), which are present as insoluble fibrils, the primary structural component of Lewy body (LB) and neurites (LN). An increasing number of non-invasive PET examinations have been used for AD, to monitor the pathological progress (hallmarks) of disease. Notwithstanding, still the need for the development of novel detection tools for other proteinopathies still remains. This review, although not exhaustively, looks at the timeline of the development of existing tracers used in the imaging of Aβ and important moments that led to the development of these tracers.
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Affiliation(s)
| | - Damiano Librizzi
- Department of Nuclear Medicine, Philipps-University of Marburg, 35043 Marburg, Germany;
| | - Behrooz Hooshyar Yousefi
- Nuclear Medicine Department, and Neuroimaging Center, Technical University of Munich, 81675 Munich, Germany;
- Department of Nuclear Medicine, Philipps-University of Marburg, 35043 Marburg, Germany;
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Watanabe H, Tatsumi H, Kaide S, Shimizu Y, Iikuni S, Ono M. Structure-Activity Relationships of Radioiodinated 6,5,6-Tricyclic Compounds for the Development of Tau Imaging Probes. ACS Med Chem Lett 2020; 11:120-126. [PMID: 32071677 DOI: 10.1021/acsmedchemlett.9b00456] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Accepted: 01/06/2020] [Indexed: 01/12/2023] Open
Abstract
Tau aggregate, which is the main component of the neurofibrillary tangle, is an attractive imaging target for diagnosing and monitoring the progression of Alzheimer's disease (AD). In this study, we designed and synthesized six radioiodinated 6,5,6-tricyclic compounds to explore novel scaffolds for tau imaging probes. On in vitro autoradiography of AD brain sections, pyridoimidazopyridine and benzimidazopyrimidine derivatives ([125I]21 and [125I]22, respectively) showed selective binding affinity for tau aggregates, whereas carbazole, pyrrolodipyridine, and pyridoimidazopyrimidine derivatives ([125I]10, [125I]12, and [125I]23, respectively) bound β-amyloid aggregates. In a biodistribution study using normal mice, [125I]21 and [125I]22 showed high initial uptakes (5.73 and 5.66% ID/g, respectively, at 2 min postinjection) into and rapid washout (0.14 and 0.10% ID/g, respectively, at 60 min postinjection) from the brain. Taken together, two novel scaffolds including pyridoimidazopyridine and benzimidazopyrimidine may be applied to develop useful tau imaging probes.
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Affiliation(s)
- Hiroyuki Watanabe
- Department of Patho-Functional Bioanalysis, Graduate School of Pharmaceutical Sciences, Kyoto University, 46-29 Yoshida Shimoadachi-cho,
Sakyo-ku, Kyoto 606-8501, Japan
| | - Haruka Tatsumi
- Department of Patho-Functional Bioanalysis, Graduate School of Pharmaceutical Sciences, Kyoto University, 46-29 Yoshida Shimoadachi-cho,
Sakyo-ku, Kyoto 606-8501, Japan
| | - Sho Kaide
- Department of Patho-Functional Bioanalysis, Graduate School of Pharmaceutical Sciences, Kyoto University, 46-29 Yoshida Shimoadachi-cho,
Sakyo-ku, Kyoto 606-8501, Japan
| | - Yoichi Shimizu
- Department of Patho-Functional Bioanalysis, Graduate School of Pharmaceutical Sciences, Kyoto University, 46-29 Yoshida Shimoadachi-cho,
Sakyo-ku, Kyoto 606-8501, Japan
| | - Shimpei Iikuni
- Department of Patho-Functional Bioanalysis, Graduate School of Pharmaceutical Sciences, Kyoto University, 46-29 Yoshida Shimoadachi-cho,
Sakyo-ku, Kyoto 606-8501, Japan
| | - Masahiro Ono
- Department of Patho-Functional Bioanalysis, Graduate School of Pharmaceutical Sciences, Kyoto University, 46-29 Yoshida Shimoadachi-cho,
Sakyo-ku, Kyoto 606-8501, Japan
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Kaneta T. PET and SPECT imaging of the brain: a review on the current status of nuclear medicine in Japan. Jpn J Radiol 2020; 38:343-357. [DOI: 10.1007/s11604-019-00901-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2019] [Accepted: 10/31/2019] [Indexed: 01/07/2023]
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White NA, Clagg K, Sirois LE, Mack KA, Al-Sayah MA, Nack WA, O'Shea PD, Zhang H, Gosselin F. Phosphoramidates as Steering Elements for Highly Selective Access to Complementary Imidazo[1,2- a]pyrimidine Isomers. Org Lett 2019; 21:9527-9531. [PMID: 31738563 DOI: 10.1021/acs.orglett.9b03702] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We report that selective N-phosphorylation of aminoimidazoles results in a key steering element that controls isomeric selectivity in the condensation of β-ethoxy acrylamides and aminoimidazoles to furnish imidazo[1,2-a]pyrimidines. We identified conditions that provide highly selective (99:1) phosphorylation at the endo- or exocyclic nitrogen. Either the 2-amino or 4-amino isomer of the (benzo)imidazo[1,2-a]pyrimidine products could be isolated in 64-95% yield. Mass spectrometric analysis and computational studies give insight into the mechanism of this exceptionally selective transformation.
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Affiliation(s)
- Nicholas A White
- Department of Small Molecule Process Chemistry , Genentech, Inc. , 1 DNA Way , South San Francisco , California 94080 , United States
| | - Kyle Clagg
- Department of Small Molecule Process Chemistry , Genentech, Inc. , 1 DNA Way , South San Francisco , California 94080 , United States
| | - Lauren E Sirois
- Department of Small Molecule Process Chemistry , Genentech, Inc. , 1 DNA Way , South San Francisco , California 94080 , United States
| | - Kyle A Mack
- Department of Small Molecule Process Chemistry , Genentech, Inc. , 1 DNA Way , South San Francisco , California 94080 , United States
| | - Mohammad A Al-Sayah
- Department of Small Molecule Analytical Chemistry , Genentech, Inc. , 1 DNA Way , South San Francisco , California 94080 , United States
| | - William A Nack
- Exemplify BioPharma , 3000 Eastpark Boulevard, Suite 500-A , Cranbury , New Jersey 08512 , United States
| | - Paul D O'Shea
- Exemplify BioPharma , 3000 Eastpark Boulevard, Suite 500-A , Cranbury , New Jersey 08512 , United States
| | - Haiming Zhang
- Department of Small Molecule Process Chemistry , Genentech, Inc. , 1 DNA Way , South San Francisco , California 94080 , United States
| | - Francis Gosselin
- Department of Small Molecule Process Chemistry , Genentech, Inc. , 1 DNA Way , South San Francisco , California 94080 , United States
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Sanabria Bohórquez S, Marik J, Ogasawara A, Tinianow JN, Gill HS, Barret O, Tamagnan G, Alagille D, Ayalon G, Manser P, Bengtsson T, Ward M, Williams SP, Kerchner GA, Seibyl JP, Marek K, Weimer RM. [ 18F]GTP1 (Genentech Tau Probe 1), a radioligand for detecting neurofibrillary tangle tau pathology in Alzheimer's disease. Eur J Nucl Med Mol Imaging 2019; 46:2077-2089. [PMID: 31254035 DOI: 10.1007/s00259-019-04399-0] [Citation(s) in RCA: 69] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2018] [Accepted: 06/11/2019] [Indexed: 01/11/2023]
Abstract
OBJECTIVE Neurofibrillary tangles (NFTs), consisting of intracellular aggregates of the tau protein, are a pathological hallmark of Alzheimer's disease (AD). Here we report the identification and initial characterization of Genentech Tau Probe 1 ([18F]GTP1), a small-molecule PET probe for imaging tau pathology in AD patients. METHODS Autoradiography using human brain tissues from AD donors and protein binding panels were used to determine [18F]GTP1 binding characteristics. Stability was evaluated in vitro and in vivo in mice and rhesus monkey. In the clinic, whole-body imaging was performed to assess biodistribution and dosimetry. Dynamic [18F]GTP1 brain imaging and input function measurement were performed on two separate days in 5 β-amyloid plaque positive (Aβ+) AD and 5 β-amyloid plaque negative (Aβ-) cognitive normal (CN) participants. Tracer kinetic modeling was applied and reproducibility was evaluated. SUVR was calculated and compared to [18F]GTP1-specific binding parameters derived from the kinetic modeling. [18F]GTP1 performance in a larger cross-sectional group of 60 Aβ+ AD participants and ten (Aβ- or Aβ+) CN was evaluated with images acquired 60 to 90 min post tracer administration. RESULTS [18F]GTP1 exhibited high affinity and selectivity for tau pathology with no measurable binding to β-amyloid plaques or MAO-B in AD tissues, or binding to other tested proteins at an affinity predicted to impede image data interpretation. In human, [18F]GTP1 exhibited favorable dosimetry and brain kinetics, and no evidence of defluorination. [18F]GTP1-specific binding was observed in cortical regions of the brain predicted to contain tau pathology in AD and exhibited low (< 4%) test-retest variability. SUVR measured in the 60 to 90-min interval post injection correlated with tracer-specific binding (slope = 1.36, r2 = 0.98). Furthermore, in a cross-sectional population, the degree of [18F]GTP1-specific binding increased with AD severity and could differentiate diagnostic cohorts. CONCLUSIONS [18F]GTP1 is a promising PET probe for the study of tau pathology in AD.
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Affiliation(s)
| | - Jan Marik
- Department of Biomedical Imaging, Genentech, Inc., 1 DNA Way, South San Francisco, CA, 94080, USA
| | - Annie Ogasawara
- Department of Biomedical Imaging, Genentech, Inc., 1 DNA Way, South San Francisco, CA, 94080, USA
| | - Jeff N Tinianow
- Department of Biomedical Imaging, Genentech, Inc., 1 DNA Way, South San Francisco, CA, 94080, USA
| | - Herman S Gill
- Department of Biomedical Imaging, Genentech, Inc., 1 DNA Way, South San Francisco, CA, 94080, USA
| | - Olivier Barret
- Invicro LLC, 60 Temple St, Suite 8A, New Haven, CT, 06510, USA
| | - Gilles Tamagnan
- Invicro LLC, 60 Temple St, Suite 8A, New Haven, CT, 06510, USA
- XingImaging, LLC, 760 Chapel Street, New Haven, CT, 06510, USA
| | - David Alagille
- Invicro LLC, 60 Temple St, Suite 8A, New Haven, CT, 06510, USA
- XingImaging, LLC, 760 Chapel Street, New Haven, CT, 06510, USA
| | - Gai Ayalon
- Department of Neuroscience, Genentech, Inc., 1 DNA Way, South San Francisco, CA, 94080, USA
| | - Paul Manser
- Clinical Biostatistics, Genentech, Inc., 1 DNA Way, South San Francisco, CA, 94080, USA
| | - Thomas Bengtsson
- Clinical Biostatistics, Genentech, Inc., 1 DNA Way, South San Francisco, CA, 94080, USA
| | - Michael Ward
- Early Clinical Development, Genentech, Inc., 1 DNA Way, South San Francisco, CA, 94080, USA
- Alector, Inc., 151 Oyster Point Blvd, South San Francisco, CA, 94080, USA
| | - Simon-Peter Williams
- Department of Biomedical Imaging, Genentech, Inc., 1 DNA Way, South San Francisco, CA, 94080, USA
| | - Geoffrey A Kerchner
- Early Clinical Development, Genentech, Inc., 1 DNA Way, South San Francisco, CA, 94080, USA
| | - John P Seibyl
- Invicro LLC, 60 Temple St, Suite 8A, New Haven, CT, 06510, USA
| | - Kenneth Marek
- Invicro LLC, 60 Temple St, Suite 8A, New Haven, CT, 06510, USA
| | - Robby M Weimer
- Department of Biomedical Imaging, Genentech, Inc., 1 DNA Way, South San Francisco, CA, 94080, USA.
- Department of Neuroscience, Genentech, Inc., 1 DNA Way, South San Francisco, CA, 94080, USA.
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Kroth H, Oden F, Molette J, Schieferstein H, Capotosti F, Mueller A, Berndt M, Schmitt-Willich H, Darmency V, Gabellieri E, Boudou C, Juergens T, Varisco Y, Vokali E, Hickman DT, Tamagnan G, Pfeifer A, Dinkelborg L, Muhs A, Stephens A. Discovery and preclinical characterization of [ 18F]PI-2620, a next-generation tau PET tracer for the assessment of tau pathology in Alzheimer's disease and other tauopathies. Eur J Nucl Med Mol Imaging 2019; 46:2178-2189. [PMID: 31264169 PMCID: PMC6667408 DOI: 10.1007/s00259-019-04397-2] [Citation(s) in RCA: 125] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2018] [Accepted: 06/10/2019] [Indexed: 01/11/2023]
Abstract
PURPOSE Tau deposition is a key pathological feature of Alzheimer's disease (AD) and other neurodegenerative disorders. The spreading of tau neurofibrillary tangles across defined brain regions corresponds to the observed level of cognitive decline in AD. Positron-emission tomography (PET) has proved to be an important tool for the detection of amyloid-beta (Aβ) aggregates in the brain, and is currently being explored for detection of pathological misfolded tau in AD and other non-AD tauopathies. Several PET tracers targeting tau deposits have been discovered and tested in humans. Limitations have been reported, especially regarding their selectivity. METHODS In our screening campaign we identified pyrrolo[2,3-b:4,5-c']dipyridine core structures with high affinity for aggregated tau. Further characterization showed that compounds containing this moiety had significantly reduced monoamine oxidase A (MAO-A) binding compared to pyrido[4,3-b]indole derivatives such as AV-1451. RESULTS Here we present preclinical data of all ten fluoropyridine regioisomers attached to the pyrrolo[2,3-b:4,5-c']dipyridine scaffold, revealing compounds 4 and 7 with superior properties. The lead candidate [18F]PI-2620 (compound 7) displayed high affinity for tau deposits in AD brain homogenate competition assays. Specific binding to pathological misfolded tau was further demonstrated by autoradiography on AD brain sections (Braak I-VI), Pick's disease and progressive supranuclear palsy (PSP) pathology, whereas no specific tracer binding was detected on brain slices from non-demented donors. In addition to its high affinity binding to tau aggregates, the compound showed excellent selectivity with no off-target binding to Aβ or MAO-A/B. Good brain uptake and fast washout were observed in healthy mice and non-human primates. CONCLUSIONS Therefore, [18F]PI-2620 was selected for clinical validation.
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Affiliation(s)
| | - Felix Oden
- Life Molecular Imaging, GmbH, Berlin, Germany
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AD molecular: Imaging tau aggregates with positron emissions tomography. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2019; 165:107-138. [PMID: 31481160 DOI: 10.1016/bs.pmbts.2019.07.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Pathologic aggregates of tau protein are observed in several neurodegenerative diseases and are used to diagnose and stage disease postmortem. Recent advances in positron emission tomography radioligands allow for the detection of aggregated tau proteins in living persons. This chapter describes the development and characterization of several positron emission tomography radioligands used to detect tau pathophysiology in vivo, and how these ligands are being used in clinical aging and neurodegenerative disease research with a focus on imaging tau aggregates in Alzheimer's disease.
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Kaide S, Watanabe H, Shimizu Y, Tatsumi H, Iikuni S, Nakamoto Y, Togashi K, Ihara M, Saji H, Ono M. 18F-labeled benzimidazopyridine derivatives for PET imaging of tau pathology in Alzheimer's disease. Bioorg Med Chem 2019; 27:3587-3594. [PMID: 31285098 DOI: 10.1016/j.bmc.2019.06.039] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2019] [Revised: 05/11/2019] [Accepted: 06/25/2019] [Indexed: 11/29/2022]
Abstract
Hyperphosphorylated tau proteins are one of the neuropathological hallmarks in the Alzheimer's disease (AD) brain. The in vivo imaging of tau aggregates with nuclear medical imaging probes is helpful for the further comprehension of and medical intervention in the AD pathology. For tau-selective PET imaging, we newly designed and synthesized 18F-labeled benzimidazopyridine (BIP) derivatives with fluoroalkylamino groups, [18F]IBIPF1 and [18F]IBIPF2, and evaluated their utilities as tau imaging probes. They both bound selectively to tau against amyloid β (Aβ) aggregates in AD brain sections in vitro, and showed good pharmacokinetics in mouse brains in vivo. Notably, [18F]IBIPF1 exhibited high tau-selectivity (Tau/Aβ ratio = 34.8), high brain uptake (6.22% ID/g at 2 min postinjection), and subsequent washout (2.77% ID/g at 30 min postinjection). In vivo analysis of radiometabolites indicated that [18F]IBIPF1 was stable against metabolism in the mouse brain. These encouraging preclinical results suggest that further structural optimization based on the BIP scaffold may lead to the development of more useful tau imaging probes.
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Affiliation(s)
- Sho Kaide
- Department of Patho-Functional Bioanalysis, Graduate School of Pharmaceutical Sciences, Kyoto University, 46-29 Yoshida Shimoadachi-cho, Sakyo-ku, Kyoto 606-8501, Japan
| | - Hiroyuki Watanabe
- Department of Patho-Functional Bioanalysis, Graduate School of Pharmaceutical Sciences, Kyoto University, 46-29 Yoshida Shimoadachi-cho, Sakyo-ku, Kyoto 606-8501, Japan
| | - Yoichi Shimizu
- Department of Patho-Functional Bioanalysis, Graduate School of Pharmaceutical Sciences, Kyoto University, 46-29 Yoshida Shimoadachi-cho, Sakyo-ku, Kyoto 606-8501, Japan; Department of Diagnostic Imaging and Nuclear Medicine, Graduate School of Medicine, Kyoto University, 54 Shogoin Kawahara-cho, Sakyo-ku, Kyoto 606-8507, Japan
| | - Haruka Tatsumi
- Department of Patho-Functional Bioanalysis, Graduate School of Pharmaceutical Sciences, Kyoto University, 46-29 Yoshida Shimoadachi-cho, Sakyo-ku, Kyoto 606-8501, Japan
| | - Shimpei Iikuni
- Department of Patho-Functional Bioanalysis, Graduate School of Pharmaceutical Sciences, Kyoto University, 46-29 Yoshida Shimoadachi-cho, Sakyo-ku, Kyoto 606-8501, Japan
| | - Yuji Nakamoto
- Department of Diagnostic Imaging and Nuclear Medicine, Graduate School of Medicine, Kyoto University, 54 Shogoin Kawahara-cho, Sakyo-ku, Kyoto 606-8507, Japan
| | - Kaori Togashi
- Department of Diagnostic Imaging and Nuclear Medicine, Graduate School of Medicine, Kyoto University, 54 Shogoin Kawahara-cho, Sakyo-ku, Kyoto 606-8507, Japan
| | - Masafumi Ihara
- Department of Stroke and Cerebrovascular Diseases, National Cerebral and Cardiovascular Center, 5-7-1 Fujishiro-dai, Suita, Osaka 565-8565, Japan
| | - Hideo Saji
- Department of Patho-Functional Bioanalysis, Graduate School of Pharmaceutical Sciences, Kyoto University, 46-29 Yoshida Shimoadachi-cho, Sakyo-ku, Kyoto 606-8501, Japan
| | - Masahiro Ono
- Department of Patho-Functional Bioanalysis, Graduate School of Pharmaceutical Sciences, Kyoto University, 46-29 Yoshida Shimoadachi-cho, Sakyo-ku, Kyoto 606-8501, Japan.
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Abstract
Purpose of Review Abnormal accumulation of tau protein is the main hallmark of tauopathies and is closely associated with neurodegeneration and cognitive impairment, whereas the advance in PET imaging provides a non-invasive detection of tau inclusions in the brain. In this review, we discuss the potential of PET imaging as a biomarker in tauopathies, the latest development of novel tau tracers with new clinical information that has been disclosed, and the opportunities for improving diagnosis and designing clinical trials in the future. Recent Findings In recent years, several first-generation tau PET tracers including [11C]PBB3, [18F]THK-5117, [18F]THK-5351 and [18F]AV-1451 have been developed and succeeded in imaging neurofibrillary pathology in vivo. Due to the common off-target binding and subcortical white matter uptake seen in the first-generation tracers, several research institutes and pharmaceutical companies have been working on developing second-generation tau PET tracers which exhibit higher binding affinity and selectivity. Summary Tau PET imaging is promising to serve as a biomarker to support differential diagnosis and monitor disease progression in many neurodegenerative diseases.
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Affiliation(s)
- Yi Ting Wang
- Neurology Imaging Unit, Division of Brain Sciences, Department of Medicine, Imperial College London, 1st Floor B Block, Hammersmith Hospital Campus, Du Cane Road, London, W12 0NN, UK
| | - Paul Edison
- Neurology Imaging Unit, Division of Brain Sciences, Department of Medicine, Imperial College London, 1st Floor B Block, Hammersmith Hospital Campus, Du Cane Road, London, W12 0NN, UK. .,Cardiff University, Cardiff, CF10 3AT, UK.
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Silva MC, Ferguson FM, Cai Q, Donovan KA, Nandi G, Patnaik D, Zhang T, Huang HT, Lucente DE, Dickerson BC, Mitchison TJ, Fischer ES, Gray NS, Haggarty SJ. Targeted degradation of aberrant tau in frontotemporal dementia patient-derived neuronal cell models. eLife 2019; 8:e45457. [PMID: 30907729 PMCID: PMC6450673 DOI: 10.7554/elife.45457] [Citation(s) in RCA: 165] [Impact Index Per Article: 33.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Accepted: 03/23/2019] [Indexed: 12/11/2022] Open
Abstract
Tauopathies are neurodegenerative diseases characterized by aberrant forms of tau protein accumulation leading to neuronal death in focal brain areas. Positron emission tomography (PET) tracers that bind to pathological tau are used in diagnosis, but there are no current therapies to eliminate these tau species. We employed targeted protein degradation technology to convert a tau PET-probe into a functional degrader of pathogenic tau. The hetero-bifunctional molecule QC-01-175 was designed to engage both tau and Cereblon (CRBN), a substrate-receptor for the E3-ubiquitin ligase CRL4CRBN, to trigger tau ubiquitination and proteasomal degradation. QC-01-175 effected clearance of tau in frontotemporal dementia (FTD) patient-derived neuronal cell models, with minimal effect on tau from neurons of healthy controls, indicating specificity for disease-relevant forms. QC-01-175 also rescued stress vulnerability in FTD neurons, phenocopying CRISPR-mediated MAPT-knockout. This work demonstrates that aberrant tau in FTD patient-derived neurons is amenable to targeted degradation, representing an important advance for therapeutics.
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Affiliation(s)
- M Catarina Silva
- Chemical Neurobiology Laboratory, Center for Genomic MedicineMassachusetts General Hospital, Harvard Medical SchoolBostonUnited States
- Department of NeurologyMassachusetts General Hospital, Harvard Medical SchoolBostonUnited States
- Department of PsychiatryMassachusetts General Hospital, Harvard Medical SchoolBostonUnited States
| | - Fleur M Ferguson
- Department of Cancer BiologyDana-Farber Cancer InstituteBostonUnited States
- Department of Biological Chemistry and Molecular PharmacologyHarvard Medical SchoolBostonUnited States
| | - Quan Cai
- Department of Cancer BiologyDana-Farber Cancer InstituteBostonUnited States
- Department of Biological Chemistry and Molecular PharmacologyHarvard Medical SchoolBostonUnited States
| | - Katherine A Donovan
- Department of Cancer BiologyDana-Farber Cancer InstituteBostonUnited States
- Department of Biological Chemistry and Molecular PharmacologyHarvard Medical SchoolBostonUnited States
| | - Ghata Nandi
- Chemical Neurobiology Laboratory, Center for Genomic MedicineMassachusetts General Hospital, Harvard Medical SchoolBostonUnited States
- Department of NeurologyMassachusetts General Hospital, Harvard Medical SchoolBostonUnited States
- Department of PsychiatryMassachusetts General Hospital, Harvard Medical SchoolBostonUnited States
| | - Debasis Patnaik
- Chemical Neurobiology Laboratory, Center for Genomic MedicineMassachusetts General Hospital, Harvard Medical SchoolBostonUnited States
- Department of NeurologyMassachusetts General Hospital, Harvard Medical SchoolBostonUnited States
- Department of PsychiatryMassachusetts General Hospital, Harvard Medical SchoolBostonUnited States
| | - Tinghu Zhang
- Department of Cancer BiologyDana-Farber Cancer InstituteBostonUnited States
- Department of Biological Chemistry and Molecular PharmacologyHarvard Medical SchoolBostonUnited States
| | - Hai-Tsang Huang
- Department of Cancer BiologyDana-Farber Cancer InstituteBostonUnited States
- Department of Biological Chemistry and Molecular PharmacologyHarvard Medical SchoolBostonUnited States
| | - Diane E Lucente
- Molecular Neurogenetics Unit, Center for Genomic MedicineMassachusetts General Hospital, Harvard Medical SchoolBostonUnited States
- MGH Frontotemporal Disorders Unit, Department of NeurologyMassachusetts General Hospital, Harvard Medical SchoolCharlestownUnited States
- Gerontology Research Unit, Department of NeurologyMassachusetts General Hospital, Harvard Medical SchoolCharlestownUnited States
- Alzheimer’s Disease Research Center, Department of NeurologyMassachusetts General Hospital, Harvard Medical SchoolCharlestownUnited States
| | - Bradford C Dickerson
- MGH Frontotemporal Disorders Unit, Department of NeurologyMassachusetts General Hospital, Harvard Medical SchoolCharlestownUnited States
- Gerontology Research Unit, Department of NeurologyMassachusetts General Hospital, Harvard Medical SchoolCharlestownUnited States
- Alzheimer’s Disease Research Center, Department of NeurologyMassachusetts General Hospital, Harvard Medical SchoolCharlestownUnited States
| | - Timothy J Mitchison
- Department of Systems BiologyHarvard Medical SchoolBostonUnited States
- Laboratory of Systems PharmacologyHarvard Medical SchoolBostonUnited States
| | - Eric S Fischer
- Department of Cancer BiologyDana-Farber Cancer InstituteBostonUnited States
- Department of Biological Chemistry and Molecular PharmacologyHarvard Medical SchoolBostonUnited States
| | - Nathanael S Gray
- Department of Cancer BiologyDana-Farber Cancer InstituteBostonUnited States
| | - Stephen J Haggarty
- Chemical Neurobiology Laboratory, Center for Genomic MedicineMassachusetts General Hospital, Harvard Medical SchoolBostonUnited States
- Department of NeurologyMassachusetts General Hospital, Harvard Medical SchoolBostonUnited States
- Department of PsychiatryMassachusetts General Hospital, Harvard Medical SchoolBostonUnited States
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Rombouts FJR, Declercq L, Andrés JI, Bottelbergs A, Chen L, Iturrino L, Leenaerts JE, Mariën J, Song F, Wintmolders C, Wuyts S, Xia CA, te Riele P, Bormans G, Vandenberghe R, Kolb H, Moechars D. Discovery of N-(4-[18F]Fluoro-5-methylpyridin-2-yl)isoquinolin-6-amine (JNJ-64326067), a New Promising Tau Positron Emission Tomography Imaging Tracer. J Med Chem 2019; 62:2974-2987. [DOI: 10.1021/acs.jmedchem.8b01759] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Frederik J. R. Rombouts
- Janssen Research & Development, Janssen Pharmaceutica N. V., Turnhoutseweg 30, B-2340 Beerse, Belgium
| | | | - José-Ignacio Andrés
- Janssen Research & Development, Janssen-Cilag S. A., C/Jarama 75A, 45007 Toledo, Spain
| | - Astrid Bottelbergs
- Janssen Research & Development, Janssen Pharmaceutica N. V., Turnhoutseweg 30, B-2340 Beerse, Belgium
| | - Lu Chen
- Janssen Research & Development, Welsh & McKean Roads, Spring House, Pennsylvania 19477, United States
| | - Laura Iturrino
- Janssen Research & Development, Janssen-Cilag S. A., C/Jarama 75A, 45007 Toledo, Spain
| | - Joseph E. Leenaerts
- Janssen Research & Development, Janssen Pharmaceutica N. V., Turnhoutseweg 30, B-2340 Beerse, Belgium
| | - Jonas Mariën
- Janssen Research & Development, Janssen Pharmaceutica N. V., Turnhoutseweg 30, B-2340 Beerse, Belgium
| | - Fengbin Song
- Janssen Research & Development, Welsh & McKean Roads, Spring House, Pennsylvania 19477, United States
| | - Cindy Wintmolders
- Janssen Research & Development, Janssen Pharmaceutica N. V., Turnhoutseweg 30, B-2340 Beerse, Belgium
| | - Stijn Wuyts
- Janssen Research & Development, Janssen Pharmaceutica N. V., Turnhoutseweg 30, B-2340 Beerse, Belgium
| | - Chunfang A. Xia
- Janssen Research & Development, 3210 Merryfield Row, San Diego, California 92121, United States
| | - Paula te Riele
- Janssen Research & Development, Janssen Pharmaceutica N. V., Turnhoutseweg 30, B-2340 Beerse, Belgium
| | | | | | - Hartmuth Kolb
- Janssen Research & Development, 3210 Merryfield Row, San Diego, California 92121, United States
| | - Diederik Moechars
- Janssen Research & Development, Janssen Pharmaceutica N. V., Turnhoutseweg 30, B-2340 Beerse, Belgium
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Leuzy A, Chiotis K, Lemoine L, Gillberg PG, Almkvist O, Rodriguez-Vieitez E, Nordberg A. Tau PET imaging in neurodegenerative tauopathies-still a challenge. Mol Psychiatry 2019; 24:1112-1134. [PMID: 30635637 PMCID: PMC6756230 DOI: 10.1038/s41380-018-0342-8] [Citation(s) in RCA: 367] [Impact Index Per Article: 73.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/18/2018] [Revised: 10/19/2018] [Accepted: 11/26/2018] [Indexed: 12/14/2022]
Abstract
The accumulation of pathological misfolded tau is a feature common to a collective of neurodegenerative disorders known as tauopathies, of which Alzheimer's disease (AD) is the most common. Related tauopathies include progressive supranuclear palsy (PSP), corticobasal syndrome (CBS), Down's syndrome (DS), Parkinson's disease (PD), and dementia with Lewy bodies (DLB). Investigation of the role of tau pathology in the onset and progression of these disorders is now possible due the recent advent of tau-specific ligands for use with positron emission tomography (PET), including first- (e.g., [18F]THK5317, [18F]THK5351, [18F]AV1451, and [11C]PBB3) and second-generation compounds [namely [18F]MK-6240, [18F]RO-948 (previously referred to as [18F]RO69558948), [18F]PI-2620, [18F]GTP1, [18F]PM-PBB3, and [18F]JNJ64349311 ([18F]JNJ311) and its derivative [18F]JNJ-067)]. In this review we describe and discuss findings from in vitro and in vivo studies using both initial and new tau ligands, including their relation to biomarkers for amyloid-β and neurodegeneration, and cognitive findings. Lastly, methodological considerations for the quantification of in vivo ligand binding are addressed, along with potential future applications of tau PET, including therapeutic trials.
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Affiliation(s)
- Antoine Leuzy
- 0000 0004 1937 0626grid.4714.6Division of Clinical Geriatrics, Center for Alzheimer Research, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Stockholm, Sweden
| | - Konstantinos Chiotis
- 0000 0004 1937 0626grid.4714.6Division of Clinical Geriatrics, Center for Alzheimer Research, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Stockholm, Sweden ,0000 0000 9241 5705grid.24381.3cTheme Neurology, Karolinska University Hospital, Stockholm, Sweden
| | - Laetitia Lemoine
- 0000 0004 1937 0626grid.4714.6Division of Clinical Geriatrics, Center for Alzheimer Research, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Stockholm, Sweden
| | - Per-Göran Gillberg
- 0000 0004 1937 0626grid.4714.6Division of Clinical Geriatrics, Center for Alzheimer Research, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Stockholm, Sweden
| | - Ove Almkvist
- 0000 0004 1937 0626grid.4714.6Division of Clinical Geriatrics, Center for Alzheimer Research, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Stockholm, Sweden ,0000 0004 1936 9377grid.10548.38Department of Psychology, Stockholm University, Stockholm, Sweden
| | - Elena Rodriguez-Vieitez
- 0000 0004 1937 0626grid.4714.6Division of Clinical Geriatrics, Center for Alzheimer Research, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Stockholm, Sweden
| | - Agneta Nordberg
- Division of Clinical Geriatrics, Center for Alzheimer Research, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Stockholm, Sweden. .,Theme Aging, Karolinska University Hospital, Stockholm, Sweden.
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Schöll M, Maass A, Mattsson N, Ashton NJ, Blennow K, Zetterberg H, Jagust W. Biomarkers for tau pathology. Mol Cell Neurosci 2018; 97:18-33. [PMID: 30529601 PMCID: PMC6584358 DOI: 10.1016/j.mcn.2018.12.001] [Citation(s) in RCA: 145] [Impact Index Per Article: 24.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2018] [Accepted: 12/01/2018] [Indexed: 12/14/2022] Open
Abstract
The aggregation of fibrils of hyperphosphorylated and C-terminally truncated microtubule-associated tau protein characterizes 80% of all dementia disorders, the most common neurodegenerative disorders. These so-called tauopathies are hitherto not curable and their diagnosis, especially at early disease stages, has traditionally proven difficult. A keystone in the diagnosis of tauopathies was the development of methods to assess levels of tau protein in vivo in cerebrospinal fluid, which has significantly improved our knowledge about these conditions. Tau proteins have also been measured in blood, but the importance of tau-related changes in blood is still unclear. The recent addition of positron emission tomography ligands to visualize, map and quantify tau pathology has further contributed with information about the temporal and spatial characteristics of tau accumulation in the living brain. Together, the measurement of tau with fluid biomarkers and positron emission tomography constitutes the basis for a highly active field of research. This review describes the current state of biomarkers for tau biomarkers derived from neuroimaging and from the analysis of bodily fluids and their roles in the detection, diagnosis and prognosis of tau-associated neurodegenerative disorders, as well as their associations with neuropathological findings, and aims to provide a perspective on how these biomarkers might be employed prospectively in research and clinical settings. Biomarkers for tau pathology are now essential to the research framework in the diagnosis of Alzheimer's disease (AD) Measurement of t- and p-tau has been possible in cerebrospinal fluid (CSF) for some time, the recent development of positron emission tomography (PET) ligands binding to tau has added the possibility to map and quantify tau in the living brain First-generation tau PET ligands bind predominantly to AD-typical 3R/4R tau isoforms and exhibit off-target binding that can limit accurate ligand uptake quantification Second-generation tau PET ligands appear to bind to comparable binding sites but exhibit fewer issues with brain off-target binding Biomarkers for tau derived from CSF analysis and PET could provide complementary information about disease state and stage At this time, T-tau, but not p-tau, can be reliably measured in plasma using ultra-sensitive immunoassays.
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Affiliation(s)
- Michael Schöll
- Wallenberg Centre for Molecular and Translational Medicine and the Department of Psychiatry and Neurochemistry, University of Gothenburg, Gothenburg, Sweden; Clinical Memory Research Unit, Lund University, Malmö, Sweden; Department of Neurodegenerative Disease, UCL Institute of Neurology, London, UK.
| | - Anne Maass
- German Center for Neurodegenerative Diseases, Magdeburg, Germany; Helen Wills Neuroscience Institute, University of California, Berkeley, USA
| | - Niklas Mattsson
- Clinical Memory Research Unit, Lund University, Malmö, Sweden; Department of Neurology, Skåne University Hospital, Lund, Sweden
| | - Nicholas J Ashton
- Wallenberg Centre for Molecular and Translational Medicine and the Department of Psychiatry and Neurochemistry, University of Gothenburg, Gothenburg, Sweden; King's College London, Institute of Psychiatry, Psychology & Neuroscience, Maurice Wohl Clinical Neuroscience Institute, London, UK
| | - Kaj Blennow
- Department of Psychiatry and Neurochemistry, University of Gothenburg, Mölndal, Sweden; Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal, Sweden
| | - Henrik Zetterberg
- Department of Neurodegenerative Disease, UCL Institute of Neurology, London, UK; Department of Psychiatry and Neurochemistry, University of Gothenburg, Mölndal, Sweden; Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal, Sweden; UK Dementia Research Institute at UCL, London, UK
| | - William Jagust
- Helen Wills Neuroscience Institute, University of California, Berkeley, USA; Molecular Biophysics and Integrated Bioimaging, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
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Femminella GD, Thayanandan T, Calsolaro V, Komici K, Rengo G, Corbi G, Ferrara N. Imaging and Molecular Mechanisms of Alzheimer's Disease: A Review. Int J Mol Sci 2018; 19:E3702. [PMID: 30469491 PMCID: PMC6321449 DOI: 10.3390/ijms19123702] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2018] [Revised: 11/13/2018] [Accepted: 11/14/2018] [Indexed: 02/07/2023] Open
Abstract
Alzheimer's disease is the most common form of dementia and is a significant burden for affected patients, carers, and health systems. Great advances have been made in understanding its pathophysiology, to a point that we are moving from a purely clinical diagnosis to a biological one based on the use of biomarkers. Among those, imaging biomarkers are invaluable in Alzheimer's, as they provide an in vivo window to the pathological processes occurring in Alzheimer's brain. While some imaging techniques are still under evaluation in the research setting, some have reached widespread clinical use. In this review, we provide an overview of the most commonly used imaging biomarkers in Alzheimer's disease, from molecular PET imaging to structural MRI, emphasising the concept that multimodal imaging would likely prove to be the optimal tool in the future of Alzheimer's research and clinical practice.
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Affiliation(s)
| | - Tony Thayanandan
- Imperial Memory Unit, Charing Cross Hospital, Imperial College London, London W6 8RF, UK.
| | - Valeria Calsolaro
- Neurology Imaging Unit, Imperial College London, London W12 0NN, UK.
| | - Klara Komici
- Department of Medicine and Health Sciences, University of Molise, 86100 Campobasso, Italy.
| | - Giuseppe Rengo
- Department of Translational Medical Sciences, Federico II University of Naples, 80131 Naples, Italy.
- Istituti Clinici Scientifici Maugeri SPA-Società Benefit, IRCCS, 82037 Telese Terme, Italy.
| | - Graziamaria Corbi
- Department of Medicine and Health Sciences, University of Molise, 86100 Campobasso, Italy.
| | - Nicola Ferrara
- Department of Translational Medical Sciences, Federico II University of Naples, 80131 Naples, Italy.
- Istituti Clinici Scientifici Maugeri SPA-Società Benefit, IRCCS, 82037 Telese Terme, Italy.
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