1
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Hurtle BT, Jana S, Cai L, Pike VW. Ligand-Based Virtual Screening as a Path to New Chemotypes for Candidate PET Radioligands for Imaging Tauopathies. J Med Chem 2024; 67:14095-14109. [PMID: 39108178 DOI: 10.1021/acs.jmedchem.4c00934] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/23/2024]
Abstract
Ligand-based virtual screening (LBVS) has rarely been tested as a method for discovering new structural scaffolds for PET radioligand development. This study used LBVS to discover potential chemotype leads for developing radioligands for PET imaging of tauopathies. ZINC12, a free database of over 12 million commercially available compounds, was searched to discover novel scaffolds based on similarities to four query compounds. Thirteen high-ranking hits were purchased and assayed for their ability to compete against three tritiated radioligands at their distinct binding sites in Alzheimer's disease brain tissue. Three hits were 2-substituted 6-methoxy naphthalenes. Synthetic elaboration of this new chemotype yielded three new ligands (25, 26, and 28) with high affinity for the [3H]6 (flortaucipur) neurofibrillary tangle binding site. Compound 28 showed remarkably high affinity (Ki, 7 nM) and other desirable properties for a candidate PET radioligand, including low topological polar surface area, moderate computed log D, and amenability for labeling with carbon-11. LBVS appears to be uniquely valuable for discovering new chemotypes for candidate PET radioligands.
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Affiliation(s)
- Bryan T Hurtle
- Molecular Imaging Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, Maryland 20892, United States
| | - Susovan Jana
- Molecular Imaging Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, Maryland 20892, United States
| | - Lisheng Cai
- Molecular Imaging Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, Maryland 20892, United States
| | - Victor W Pike
- Molecular Imaging Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, Maryland 20892, United States
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2
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Chisholm TS, Hunter CA. A closer look at amyloid ligands, and what they tell us about protein aggregates. Chem Soc Rev 2024; 53:1354-1374. [PMID: 38116736 DOI: 10.1039/d3cs00518f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2023]
Abstract
The accumulation of amyloid fibrils is characteristic of neurodegenerative diseases such as Alzheimer's disease (AD) and Parkinson's disease. Detecting these fibrils with fluorescent or radiolabelled ligands is one strategy for diagnosing and better understanding these diseases. A vast number of amyloid-binding ligands have been reported in the literature as a result. To obtain a better understanding of how amyloid ligands bind, we have compiled a database of 3457 experimental dissociation constants for 2076 unique amyloid-binding ligands. These ligands target Aβ, tau, or αSyn fibrils, as well as relevant biological samples including AD brain homogenates. From this database significant variation in the reported dissociation constants of ligands was found, possibly due to differences in the morphology of the fibrils being studied. Ligands were also found to bind to Aβ(1-40) and Aβ(1-42) fibrils with similar affinities, whereas a greater difference was found for binding to Aβ and tau or αSyn fibrils. Next, the binding of ligands to fibrils was shown to be largely limited by the hydrophobic effect. Some Aβ ligands do not fit into this hydrophobicity-limited model, suggesting that polar interactions can play an important role when binding to this target. Finally several binding site models were outlined for amyloid fibrils that describe what ligands target what binding sites. These models provide a foundation for interpreting and designing site-specific binding assays.
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Affiliation(s)
- Timothy S Chisholm
- Yusuf Hamied Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1 EW, UK.
| | - Christopher A Hunter
- Yusuf Hamied Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1 EW, UK.
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3
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Malyshka D, Jimenez-Harrison D, Kuret J. Sedimentation and Laser Light Scattering Methods for Quantifying Synthetic Tau Aggregation Propensity. Methods Mol Biol 2024; 2754:117-129. [PMID: 38512664 DOI: 10.1007/978-1-0716-3629-9_7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/23/2024]
Abstract
Tau aggregation assays detect and quantify the conversion of soluble tau monomers into species having filamentous or oligomeric structure. Assays for filamentous aggregates in cross-β-sheet conformation leverage optical, biochemical, or biophysical methods, each with their own advantages and throughput capacity. Here we provide protocols for two medium-throughput assays based on sedimentation and laser light scattering and compare their performance, their utility for characterizing tau aggregation dynamics, and their limitations relative to other approaches. Additionally, a protocol for transmission electron microscopy analysis is updated so as to be compatible with the truncated tau variants that have emerged as powerful tools for interrogating the structural basis of tau polymorphism. Together these methods contribute to a rich tool kit for interrogating tau aggregation kinetics and propensity over a wide range of experimental conditions.
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Affiliation(s)
- Dmitry Malyshka
- Medical Scientist Training Program, The Ohio State University College of Medicine, Columbus, OH, USA
| | - Daniela Jimenez-Harrison
- Medical Scientist Training Program, The Ohio State University College of Medicine, Columbus, OH, USA
| | - Jeff Kuret
- Department of Biological Chemistry and Pharmacology, The Ohio State University College of Medicine, Columbus, OH, USA.
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4
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Barbone GE, Bravin A, Mittone A, Pacureanu A, Mascio G, Di Pietro P, Kraiger MJ, Eckermann M, Romano M, Hrabě de Angelis M, Cloetens P, Bruno V, Battaglia G, Coan P. X-ray multiscale 3D neuroimaging to quantify cellular aging and neurodegeneration postmortem in a model of Alzheimer’s disease. Eur J Nucl Med Mol Imaging 2022; 49:4338-4357. [PMID: 35852558 PMCID: PMC9606093 DOI: 10.1007/s00259-022-05896-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2022] [Accepted: 06/25/2022] [Indexed: 01/19/2023]
Abstract
Abstract
Purpose
Modern neuroimaging lacks the tools necessary for whole-brain, anatomically dense neuronal damage screening. An ideal approach would include unbiased histopathologic identification of aging and neurodegenerative disease.
Methods
We report the postmortem application of multiscale X-ray phase-contrast computed tomography (X-PCI-CT) for the label-free and dissection-free organ-level to intracellular-level 3D visualization of distinct single neurons and glia. In deep neuronal populations in the brain of aged wild-type and of 3xTgAD mice (a triply-transgenic model of Alzheimer’s disease), we quantified intracellular hyperdensity, a manifestation of aging or neurodegeneration.
Results
In 3xTgAD mice, the observed hyperdensity was identified as amyloid-β and hyper-phosphorylated tau protein deposits with calcium and iron involvement, by correlating the X-PCI-CT data to immunohistochemistry, X-ray fluorescence microscopy, high-field MRI, and TEM. As a proof-of-concept, X-PCI-CT was used to analyze hippocampal and cortical brain regions of 3xTgAD mice treated with LY379268, selective agonist of group II metabotropic glutamate receptors (mGlu2/3 receptors). Chronic pharmacologic activation of mGlu2/3 receptors significantly reduced the hyperdensity particle load in the ventral cortical regions of 3xTgAD mice, suggesting a neuroprotective effect with locoregional efficacy.
Conclusions
This multiscale micro-to-nano 3D imaging method based on X-PCI-CT enabled identification and quantification of cellular and sub-cellular aging and neurodegeneration in deep neuronal and glial cell populations in a transgenic model of Alzheimer’s disease. This approach quantified the localized and intracellular neuroprotective effects of pharmacological activation of mGlu2/3 receptors.
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5
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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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Ali TFS, Ciftci HI, Radwan MO, Roshdy E, Shawky AM, Abourehab MAS, Tateishi H, Otsuka M, Fujita M. Discovery of Azaindolin-2-One as a Dual Inhibitor of GSK3β and Tau Aggregation with Potential Neuroprotective Activity. Pharmaceuticals (Basel) 2022; 15:ph15040426. [PMID: 35455423 PMCID: PMC9029746 DOI: 10.3390/ph15040426] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Revised: 03/22/2022] [Accepted: 03/29/2022] [Indexed: 11/29/2022] Open
Abstract
The inhibition of glycogen synthase kinase 3β (GSK3β) activity through pharmacological intervention represents a promising approach for treating challenging neurodegenerative disorders like Alzheimer’s disease. Similarly, abnormal tau aggregate accumulation in neurons is a hallmark of various neurodegenerative diseases. We introduced new dual GSK3β/tau aggregation inhibitors due to the excellent clinical outcome of multitarget drugs. Compound (E)-2f stands out among the synthesized inhibitors as a promising GSK3β inhibitor (IC50 1.7 µM) with a pronounced tau anti-aggregation effect in a cell-based model of tauopathy. Concurrently, (E)-2f was demonstrated to be non-toxic to normal cells, making it a promising neuroprotective lead compound that needs further investigation.
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Affiliation(s)
- Taha F. S. Ali
- Medicinal Chemistry Department, Faculty of Pharmacy, Minia University, Minia 61519, Egypt;
- Medicinal and Biological Chemistry Science Farm Joint Research Laboratory, Faculty of Life Sciences, Kumamoto University, Kumamoto 862-0973, Japan; (H.I.C.); (M.O.R.); (H.T.); (M.O.)
- Correspondence: (T.F.S.A.); (M.F.); Tel.: +20-10-6983-5295 (T.F.S.A.); +81-96-371-4622 (M.F.)
| | - Halil I. Ciftci
- Medicinal and Biological Chemistry Science Farm Joint Research Laboratory, Faculty of Life Sciences, Kumamoto University, Kumamoto 862-0973, Japan; (H.I.C.); (M.O.R.); (H.T.); (M.O.)
- Department of Drug Discovery, Science Farm, Ltd., Kumamoto 862-0976, Japan
| | - Mohamed O. Radwan
- Medicinal and Biological Chemistry Science Farm Joint Research Laboratory, Faculty of Life Sciences, Kumamoto University, Kumamoto 862-0973, Japan; (H.I.C.); (M.O.R.); (H.T.); (M.O.)
- National Research Centre, Chemistry of Natural Compounds Department, Pharmaceutical and Drug Industries Research Division, Dokki, Cairo 12622, Egypt
| | - Eslam Roshdy
- Medicinal Chemistry Department, Faculty of Pharmacy, Minia University, Minia 61519, Egypt;
- Department of Chemistry, Graduate School of Science, Hiroshima University, Higashi-Hiroshima, Hiroshima 739-8526, Japan
| | - Ahmed M. Shawky
- Science and Technology Unit (STU), Umm Al-Qura University, Makkah 21955, Saudi Arabia;
- Central Laboratory for Micro-Analysis, Minia University, Minia 61519, Egypt
| | - Mohammed A. S. Abourehab
- Department of Pharmaceutics, Faculty of Pharmacy, Umm Al-Qura University, Makkah 21955, Saudi Arabia;
| | - Hiroshi Tateishi
- Medicinal and Biological Chemistry Science Farm Joint Research Laboratory, Faculty of Life Sciences, Kumamoto University, Kumamoto 862-0973, Japan; (H.I.C.); (M.O.R.); (H.T.); (M.O.)
| | - Masami Otsuka
- Medicinal and Biological Chemistry Science Farm Joint Research Laboratory, Faculty of Life Sciences, Kumamoto University, Kumamoto 862-0973, Japan; (H.I.C.); (M.O.R.); (H.T.); (M.O.)
- Department of Drug Discovery, Science Farm, Ltd., Kumamoto 862-0976, Japan
| | - Mikako Fujita
- Medicinal and Biological Chemistry Science Farm Joint Research Laboratory, Faculty of Life Sciences, Kumamoto University, Kumamoto 862-0973, Japan; (H.I.C.); (M.O.R.); (H.T.); (M.O.)
- Correspondence: (T.F.S.A.); (M.F.); Tel.: +20-10-6983-5295 (T.F.S.A.); +81-96-371-4622 (M.F.)
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7
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Zeng Q, Cui M. Current Progress in the Development of Probes for Targeting α-Synuclein Aggregates. ACS Chem Neurosci 2022; 13:552-571. [PMID: 35167269 DOI: 10.1021/acschemneuro.1c00877] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
α-Synuclein aggregates abnormally into intracellular inclusions in Parkinson's disease (PD), dementia with Lewy bodies (DLB), multiple system atrophy (MSA), and many other neurological disorders, closely connecting with their pathogenesis. The accurate tracking of α-synuclein by targeting probes is of great significance for early diagnosis, disease monitoring, and drug development. However, there have been no promising α-synuclein targeting probes for clinical application reported so far. This overview focuses on various potential α-synuclein targeting probes reported in the past two decades, including small-molecule fluorescent probes and radiolabeled probes. We provide the current status of the development of the small molecular α-synuclein imaging probes, including properties of promising imaging molecules, strategies of processing new probes, limited progress, and growth prospects in this field, expecting to help in the further development of α-synuclein targeting probes.
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Affiliation(s)
- Qi Zeng
- Key Laboratory of Radiopharmaceuticals, Ministry of Education, Beijing Normal University, Beijing 100875, China
| | - Mengchao Cui
- Key Laboratory of Radiopharmaceuticals, Ministry of Education, Beijing Normal University, Beijing 100875, China
- Center for Advanced Materials Research, Advanced Institute of Natural Sciences, Beijing Normal University at Zhuhai, Zhuhai 519087, China
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8
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Alpha-Synuclein PET Tracer Development-An Overview about Current Efforts. Pharmaceuticals (Basel) 2021; 14:ph14090847. [PMID: 34577548 PMCID: PMC8466155 DOI: 10.3390/ph14090847] [Citation(s) in RCA: 52] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2021] [Revised: 08/16/2021] [Accepted: 08/17/2021] [Indexed: 12/18/2022] Open
Abstract
Neurodegenerative diseases such as Parkinson’s disease (PD) are manifested by inclusion bodies of alpha-synuclein (α-syn) also called α-synucleinopathies. Detection of these inclusions is thus far only possible by histological examination of postmortem brain tissue. The possibility of non-invasively detecting α-syn will therefore provide valuable insights into the disease progression of α-synucleinopathies. In particular, α-syn imaging can quantify changes in monomeric, oligomeric, and fibrillic α-syn over time and improve early diagnosis of various α-synucleinopathies or monitor treatment progress. Positron emission tomography (PET) is a non-invasive in vivo imaging technique that can quantify target expression and drug occupancies when a suitable tracer exists. As such, novel α-syn PET tracers are highly sought after. The development of an α-syn PET tracer faces several challenges. For example, the low abundance of α-syn within the brain necessitates the development of a high-affinity ligand. Moreover, α-syn depositions are, in contrast to amyloid proteins, predominantly localized intracellularly, limiting their accessibility. Furthermore, another challenge is the ligand selectivity over structurally similar amyloids such as amyloid-beta or tau, which are often co-localized with α-syn pathology. The lack of a defined crystal structure of α-syn has also hindered rational drug and tracer design efforts. Our objective for this review is to provide a comprehensive overview of current efforts in the development of selective α-syn PET tracers.
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9
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Kreiser RP, Wright AK, Block NR, Hollows JE, Nguyen LT, LeForte K, Mannini B, Vendruscolo M, Limbocker R. Therapeutic Strategies to Reduce the Toxicity of Misfolded Protein Oligomers. Int J Mol Sci 2020; 21:ijms21228651. [PMID: 33212787 PMCID: PMC7696907 DOI: 10.3390/ijms21228651] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2020] [Revised: 11/04/2020] [Accepted: 11/05/2020] [Indexed: 02/07/2023] Open
Abstract
The aberrant aggregation of proteins is implicated in the onset and pathogenesis of a wide range of neurodegenerative disorders, including Alzheimer’s and Parkinson’s diseases. Mounting evidence indicates that misfolded protein oligomers produced as intermediates in the aggregation process are potent neurotoxic agents in these diseases. Because of the transient and heterogeneous nature of these elusive aggregates, however, it has proven challenging to develop therapeutics that can effectively target them. Here, we review approaches aimed at reducing oligomer toxicity, including (1) modulating the oligomer populations (e.g., by altering the kinetics of aggregation by inhibiting, enhancing, or redirecting the process), (2) modulating the oligomer properties (e.g., through the size–hydrophobicity–toxicity relationship), (3) modulating the oligomer interactions (e.g., by protecting cell membranes by displacing oligomers), and (4) reducing oligomer toxicity by potentiating the protein homeostasis system. We analyze examples of these complementary approaches, which may lead to the development of compounds capable of preventing or treating neurodegenerative disorders associated with protein aggregation.
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Affiliation(s)
- Ryan P. Kreiser
- Department of Chemistry and Life Science, United States Military Academy, West Point, NY 10996, USA; (R.P.K.); (A.K.W.); (N.R.B.); (J.E.H.); (L.T.N.); (K.L.)
| | - Aidan K. Wright
- Department of Chemistry and Life Science, United States Military Academy, West Point, NY 10996, USA; (R.P.K.); (A.K.W.); (N.R.B.); (J.E.H.); (L.T.N.); (K.L.)
| | - Natalie R. Block
- Department of Chemistry and Life Science, United States Military Academy, West Point, NY 10996, USA; (R.P.K.); (A.K.W.); (N.R.B.); (J.E.H.); (L.T.N.); (K.L.)
| | - Jared E. Hollows
- Department of Chemistry and Life Science, United States Military Academy, West Point, NY 10996, USA; (R.P.K.); (A.K.W.); (N.R.B.); (J.E.H.); (L.T.N.); (K.L.)
| | - Lam T. Nguyen
- Department of Chemistry and Life Science, United States Military Academy, West Point, NY 10996, USA; (R.P.K.); (A.K.W.); (N.R.B.); (J.E.H.); (L.T.N.); (K.L.)
| | - Kathleen LeForte
- Department of Chemistry and Life Science, United States Military Academy, West Point, NY 10996, USA; (R.P.K.); (A.K.W.); (N.R.B.); (J.E.H.); (L.T.N.); (K.L.)
| | - Benedetta Mannini
- Centre for Misfolding Diseases, Department of Chemistry, University of Cambridge, Cambridge CB2 1EW, UK;
| | - Michele Vendruscolo
- Centre for Misfolding Diseases, Department of Chemistry, University of Cambridge, Cambridge CB2 1EW, UK;
- Correspondence: (M.V.); (R.L.)
| | - Ryan Limbocker
- Department of Chemistry and Life Science, United States Military Academy, West Point, NY 10996, USA; (R.P.K.); (A.K.W.); (N.R.B.); (J.E.H.); (L.T.N.); (K.L.)
- Correspondence: (M.V.); (R.L.)
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10
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Adolfsson DE, Tyagi M, Singh P, Deuschmann A, Ådén J, Gharibyan AL, Jayaweera SW, Lindgren AEG, Olofsson A, Almqvist F. Intramolecular Povarov Reactions for the Synthesis of Chromenopyridine Fused 2-Pyridone Polyheterocycles Binding to α-Synuclein and Amyloid-β Fibrils. J Org Chem 2020; 85:14174-14189. [PMID: 33099999 PMCID: PMC7660745 DOI: 10.1021/acs.joc.0c01699] [Citation(s) in RCA: 10] [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: 07/16/2020] [Indexed: 12/29/2022]
Abstract
A BF3·OEt2 catalyzed intramolecular Povarov reaction was used to synthesize 15 chromenopyridine fused thiazolino-2-pyridone peptidomimetics. The reaction works with several O-alkylated salicylaldehydes and amino functionalized thiazolino-2-pyridones, to generate polyheterocycles with diverse substitution. The synthesized compounds were screened for their ability to bind α-synuclein and amyloid β fibrils in vitro. Analogues substituted with a nitro group bind to mature amyloid fibrils, and the activity moreover depends on the positioning of this functional group.
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Affiliation(s)
| | - Mohit Tyagi
- Umeå University, Department of Chemistry, 901 87 Umeå, Sweden
| | - Pardeep Singh
- Umeå University, Department of Chemistry, 901 87 Umeå, Sweden
| | | | - Jörgen Ådén
- Umeå University, Department of Chemistry, 901 87 Umeå, Sweden
| | | | | | | | - Anders Olofsson
- Umeå University, Department of Chemistry, 901 87 Umeå, Sweden
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11
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Mahendra VP, Yogendra Prasad K, Ganesan P, Kumar R. Mechanism of rutin mediated inhibition of insulin amyloid formation and protection of Neuro-2a cells from fibril-induced apoptosis. Mol Biol Rep 2020; 47:2811-2820. [DOI: 10.1007/s11033-020-05393-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2019] [Accepted: 03/24/2020] [Indexed: 01/13/2023]
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12
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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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13
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Crowe A, Henderson MJ, Anderson J, Titus SA, Zakharov A, Simeonov A, Buist A, Delay C, Moechars D, Trojanowski JQ, Lee VMY, Brunden KR. Compound screening in cell-based models of tau inclusion formation: Comparison of primary neuron and HEK293 cell assays. J Biol Chem 2020; 295:4001-4013. [PMID: 32034092 DOI: 10.1074/jbc.ra119.010532] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2019] [Revised: 02/04/2020] [Indexed: 12/11/2022] Open
Abstract
The hallmark pathological features of Alzheimer's disease (AD) brains are senile plaques, comprising β-amyloid (Aβ) peptides, and neuronal inclusions formed from tau protein. These plaques form 10-20 years before AD symptom onset, whereas robust tau pathology is more closely associated with symptoms and correlates with cognitive status. This temporal sequence of AD pathology development, coupled with repeated clinical failures of Aβ-directed drugs, suggests that molecules that reduce tau inclusions have therapeutic potential. Few tau-directed drugs are presently in clinical testing, in part because of the difficulty in identifying molecules that reduce tau inclusions. We describe here two cell-based assays of tau inclusion formation that we employed to screen for compounds that inhibit tau pathology: a HEK293 cell-based tau overexpression assay, and a primary rat cortical neuron assay with physiological tau expression. Screening a collection of ∼3500 pharmaceutical compounds with the HEK293 cell tau aggregation assay, we obtained only a low number of hit compounds. Moreover, these compounds generally failed to inhibit tau inclusion formation in the cortical neuron assay. We then screened the Prestwick library of mostly approved drugs in the cortical neuron assay, leading to the identification of a greater number of tau inclusion inhibitors. These included four dopamine D2 receptor antagonists, with D2 receptors having previously been suggested to regulate tau inclusions in a Caenorhabditis elegans model. These results suggest that neurons, the cells most affected by tau pathology in AD, are very suitable for screening for tau inclusion inhibitors.
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Affiliation(s)
- Alex Crowe
- Center for Neurodegenerative Disease Research, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104
| | - Mark J Henderson
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, Maryland 20850
| | - Johnathon Anderson
- Center for Neurodegenerative Disease Research, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104
| | - Steven A Titus
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, Maryland 20850
| | - Alexey Zakharov
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, Maryland 20850
| | - Anton Simeonov
- National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, Maryland 20850
| | - Arjan Buist
- Department of Neuroscience, Janssen Research and Development, Janssen Pharmaceutica NV, B-2340 Beerse, Belgium
| | - Charlotte Delay
- Department of Neuroscience, Janssen Research and Development, Janssen Pharmaceutica NV, B-2340 Beerse, Belgium
| | - Diederik Moechars
- Department of Neuroscience, Janssen Research and Development, Janssen Pharmaceutica NV, B-2340 Beerse, Belgium
| | - John Q Trojanowski
- Center for Neurodegenerative Disease Research, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104
| | - Virginia M-Y Lee
- Center for Neurodegenerative Disease Research, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104
| | - Kurt R Brunden
- Center for Neurodegenerative Disease Research, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104
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14
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Pharmacological investigation of quinoxaline-bisthiazoles as multitarget-directed ligands for the treatment of Alzheimer's disease. Bioorg Chem 2019; 89:102992. [PMID: 31174042 DOI: 10.1016/j.bioorg.2019.102992] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2018] [Revised: 04/07/2019] [Accepted: 05/17/2019] [Indexed: 12/28/2022]
Abstract
Alzheimer's disease (AD) is the most prevalent disease of old age leading to dementia. Complex AD pathogenesis involves multiple factors viz. amyloid plaque formation, neurofibrillary tangles and inflammation. Herein we report of a new series of quinoxaline-bisthiazoles as multitarget-directed ligands (MTDLs) targeting BACE-1 and inflammation concurrently. Virtual screening of a library of novel quinoxaline-bisthiazoles was performed by docking studies. The most active molecules from the docking library were taken up for synthesis and characterized by spectral data. Compounds 8a-8n showed BACE-1 inhibition in micro molar range. One of the compounds, 8n showed BACE-1 inhibition at IC50 of 3 ± 0.07 µM. Rat paw edema inhibition in acute and chronic models of inflammation were obtained at 69 ± 0.45% and 55 ± 0.7%, respectively. Compound 8n also showed noteworthy results in AlCl3 induced AD model. The treated rats exhibited excellent antiamnesic, antiamyloid, antioxidant, and neuroprotective properties. Behavioural parameters suggested improved cognitive functions which further validates the testimony of present study. Moreover, compound 8n was found to have inherent gastrointestinal safety. This new string of quinoxaline-bisthiazoles were identified as effective lead for the generation of potent MTDLs and compound 8n was found to showcase qualities to tackle AD pathogenesis.
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15
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Savelieff MG, Nam G, Kang J, Lee HJ, Lee M, Lim MH. Development of Multifunctional Molecules as Potential Therapeutic Candidates for Alzheimer’s Disease, Parkinson’s Disease, and Amyotrophic Lateral Sclerosis in the Last Decade. Chem Rev 2018; 119:1221-1322. [DOI: 10.1021/acs.chemrev.8b00138] [Citation(s) in RCA: 270] [Impact Index Per Article: 45.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Masha G. Savelieff
- SciGency Science Communications, Ann Arbor, Michigan 48104, United States
| | - Geewoo Nam
- Department of Chemistry, Ulsan National Institute of Science and Technology (UNIST), Ulsan 44919, Republic of Korea
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Republic of Korea
| | - Juhye Kang
- Department of Chemistry, Ulsan National Institute of Science and Technology (UNIST), Ulsan 44919, Republic of Korea
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Republic of Korea
| | - Hyuck Jin Lee
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Republic of Korea
| | - Misun Lee
- Department of Chemistry, Ulsan National Institute of Science and Technology (UNIST), Ulsan 44919, Republic of Korea
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Republic of Korea
| | - Mi Hee Lim
- Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Republic of Korea
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16
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Abstract
PURPOSE OF REVIEW To present the new PET markers that could become in the coming years, relevant to advanced clinical approaches to dementia diagnosis, drug trials, and treatment strategies and discuss their advantages and limitations. RECENT FINDINGS The most advanced new PET tracers are the markers of the amyloid plaques, the τ compounds and the tracers of the translocator protein as markers of neuroinflammation. The main advantages but also the weaknesses of each of these markers are discussed. The main pitfall remains the heterogeneity of the available results that cast doubt to a rapid introduction of these new ligands in clinical practice. SUMMARY With the advent of biomarkers in clinical management and findings of molecular neuroimaging studies in the evaluation of patients with suspected dementia, the impact of functional neuroimaging has increased considerably these last years and has been integrated into many clinical guidelines in the field of dementia. In addition to conventional single PET brain perfusion and dopaminergic neurotransmission, 18F-fluorodeoxyglucose (18F-FDG) PET is used in advanced diagnosis procedures. Furthermore, new tracers are being developed to quantify key neuropathological features in the brain tissue as highly specific diagnosis is crucial to comply with the global medical and public health objectives in this domain. A strategic road map for further developments, adapted from the approach to cancer biomarkers, should be proposed so as to optimize the rationale of the PET-based molecular diagnosis of Alzheimer's disease and related disorders.
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17
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Verwilst P, Kim HS, Kim S, Kang C, Kim JS. Shedding light on tau protein aggregation: the progress in developing highly selective fluorophores. Chem Soc Rev 2018; 47:2249-2265. [DOI: 10.1039/c7cs00706j] [Citation(s) in RCA: 79] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The development of highly selective fluorophores for tau protein aggregates, a key feature of Alzheimer's disease, is highlighted.
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Affiliation(s)
| | | | - Soobin Kim
- Department of Chemistry
- Korea University
- Seoul 02841
- Korea
| | - Chulhun Kang
- The School of East-West Medical Science
- Kyung Hee University
- Yongin 17104
- Korea
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18
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Zhu B, Zhang T, Jiang Q, Li Y, Fu Y, Dai J, Li G, Qi Q, Cheng Y. Synthesis and evaluation of pyrazine and quinoxaline fluorophores for in vivo detection of cerebral tau tangles in Alzheimer's models. Chem Commun (Camb) 2018; 54:11558-11561. [PMID: 30204164 DOI: 10.1039/c8cc06897f] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The quinoxaline derivative 3b is a candidate probe for fluorescence turn-on detection of tau tangles both in vitro and in mice in vivo.
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Affiliation(s)
- Biyue Zhu
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry
- Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial Technology
- West China School of Pharmacy
- Sichuan University
- Chengdu
| | - Ting Zhang
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry
- Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial Technology
- West China School of Pharmacy
- Sichuan University
- Chengdu
| | - Qian Jiang
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry
- Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial Technology
- West China School of Pharmacy
- Sichuan University
- Chengdu
| | - Ying Li
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry
- Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial Technology
- West China School of Pharmacy
- Sichuan University
- Chengdu
| | - Yu Fu
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry
- Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial Technology
- West China School of Pharmacy
- Sichuan University
- Chengdu
| | - Jiapei Dai
- Wuhan Institute for Neuroscience and Neuroengineering
- South-Central University for Nationalities
- Wuhan 430074
- China
| | - Ge Li
- Guangdong Laboratory Animals Monitoring Institute
- Guangdong Provincial Key Laboratory of Laboratory Animals
- Guangzhou 510663
- China
| | - Qingrong Qi
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry
- Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial Technology
- West China School of Pharmacy
- Sichuan University
- Chengdu
| | - Yan Cheng
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry
- Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial Technology
- West China School of Pharmacy
- Sichuan University
- Chengdu
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19
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Fisher E, Zhao Y, Richardson R, Janik M, Buell AK, Aigbirhio FI, Tóth G. Detection and Characterization of Small Molecule Interactions with Fibrillar Protein Aggregates Using Microscale Thermophoresis. ACS Chem Neurosci 2017. [PMID: 28640595 DOI: 10.1021/acschemneuro.7b00228] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Neurodegenerative diseases such as Parkinson's and Alzheimer's disease share the pathological hallmark of fibrillar protein aggregates. The specific detection of these protein aggregates by positron emission tomography (PET) in the patient brain can yield valuable information for diagnosis and disease progression. However, the identification of novel small compounds that bind fibrillar protein aggregates has been a challenge. In this study, microscale thermophoresis (MST) was applied to assess the binding affinity of known small molecule ligands of α-synuclein fibrils, which were also tested in parallel in a thioflavin T fluorescence competition assay for further validation. In addition, a MST assay was also developed for the detection of the interaction between a variety of small molecules and tau fibrils. The results of this study demonstrate that MST is a powerful and practical methodology to quantify interactions between small molecules and protein fibrillar aggregates, which suggests that it can be applied for the identification and development of PET radioligands and potentially of therapeutic candidates for protein misfolding diseases.
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Affiliation(s)
- Emily Fisher
- Molecular Imaging
Chemistry Laboratory, Wolfson Brain Imaging Centre, Department of
Clinical Neurosciences, University of Cambridge, Cambridge CB2 0QQ, U.K
| | - Yanyan Zhao
- Molecular Imaging
Chemistry Laboratory, Wolfson Brain Imaging Centre, Department of
Clinical Neurosciences, University of Cambridge, Cambridge CB2 0QQ, U.K
| | - Robert Richardson
- Molecular Imaging
Chemistry Laboratory, Wolfson Brain Imaging Centre, Department of
Clinical Neurosciences, University of Cambridge, Cambridge CB2 0QQ, U.K
| | - Malgorzata Janik
- MTA-TTK-NAP
B, Drug Discovery Research Group, Neurodegenerative Diseases, Institute
of Organic Chemistry, Research Center for Natural Sciences, Hungarian Academy of Sciences, Budapest 1051, Hungary
| | - Alexander K. Buell
- Department of Chemistry, University of Cambridge, Cambridge CB2 1EW, U.K
| | - Franklin I. Aigbirhio
- Molecular Imaging
Chemistry Laboratory, Wolfson Brain Imaging Centre, Department of
Clinical Neurosciences, University of Cambridge, Cambridge CB2 0QQ, U.K
| | - Gergely Tóth
- Molecular Imaging
Chemistry Laboratory, Wolfson Brain Imaging Centre, Department of
Clinical Neurosciences, University of Cambridge, Cambridge CB2 0QQ, U.K
- MTA-TTK-NAP
B, Drug Discovery Research Group, Neurodegenerative Diseases, Institute
of Organic Chemistry, Research Center for Natural Sciences, Hungarian Academy of Sciences, Budapest 1051, Hungary
- Cantabio Pharmaceuticals Inc., Sunnyvale, California 94085, United States
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20
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Abstract
Newly developed tissue clearing techniques can be used to render intact tissues transparent. When combined with fluorescent labeling technologies and optical sectioning microscopy, this allows visualization of fine structure in three dimensions. Gene-transfection techniques have proved very useful in visualizing cellular structures in animal models, but they are not applicable to human brain tissue. Here, we discuss the characteristics of an ideal chemical fluorescent probe for use in brain and other cleared tissues, and offer a comprehensive overview of currently available chemical probes. We describe their working principles and compare their performance with the goal of simplifying probe selection for neuropathologists and stimulating probe development by chemists. We propose several approaches for the development of innovative chemical labeling methods which, when combined with tissue clearing, have the potential to revolutionize how we study the structure and function of the human brain.
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Affiliation(s)
- Hei Ming Lai
- School of Biomedical Sciences, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong SAR, China; Neuropathology Unit, Division of Brain Sciences, Department of Medicine, Imperial College London, London W12 0NN, UK.
| | - Wai-Lung Ng
- Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Oxford OX1 3TA, UK
| | - Steve M Gentleman
- Neuropathology Unit, Division of Brain Sciences, Department of Medicine, Imperial College London, London W12 0NN, UK.
| | - Wutian Wu
- School of Biomedical Sciences, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong SAR, China; State Key Laboratory of Brain and Cognitive Sciences, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong SAR, China; Research Center of Reproduction, Development and Growth, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong SAR, China; Joint Laboratory of Jinan University and The University of Hong Kong, GHM Institute of CNS Regeneration, Jinan University, Guangzhou 510632, China.
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21
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Abstract
Alzheimer's disease (AD) is a chronic neurodegenerative disorder and the most common cause of dementia among the elderly population. The good correlation between the density and neocortical spread of neurofibrillary tangles (NFTs) and the severity of cognitive impairment offers an opportunity to use a noninvasive imaging technique such as positron emission tomography (PET) for early diagnosis and staging of the disease. PET imaging of NFTs holds promise not only as a diagnostic tool but also because it may enable the development of disease-modifying therapeutics for AD. In this review, we focus on the structural diversity of tau PET tracers, the challenges related to identifying high-affinity and highly selective NFT ligands, and recent progress in the clinical development of tau PET radioligands.
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Affiliation(s)
- Hartmuth C Kolb
- Janssen Research and Development, Neuroscience Biomarkers, San Diego, California 92121
| | - José Ignacio Andrés
- Janssen Research and Development, Discovery Sciences, Janssen-Cilag S.A., 45007 Toledo, Spain
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22
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Current status of the development of PET radiotracers for imaging alpha synuclein aggregates in Lewy bodies and Lewy neurites. Clin Transl Imaging 2016. [DOI: 10.1007/s40336-016-0217-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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23
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Abstract
In vivo imaging of tau deposits is providing a better understanding of the temporal and spatial tau deposition in the brain, allowing a more comprehensive insight into the causes, diagnoses, and potentially treatment of tauopathies such as Alzheimer's disease, progressive supranuclear palsy, corticobasal syndrome, chronic traumatic encephalopathy, and some variants of frontotemporal lobar degeneration. The assessment of tau deposition in the brain over time will allow a deeper understanding of the relationship between tau and other variables such as cognition, genotype, and neurodegeneration, as well as assessing the role tau plays in ageing. Preliminary human studies suggest that tau imaging could also be used as a diagnostic, prognostic, and theranostic biomarker, as well as a surrogate marker for target engagement, patient recruitment, and efficacy monitoring for disease-specific therapeutic trials.
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Affiliation(s)
- Victor L Villemagne
- Department of Molecular Imaging & Therapy, Centre for PET, Austin Health, Melbourne, Australia; The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Melbourne, Australia; Department of Medicine, The University of Melbourne, Melbourne, Australia
| | | | - Christopher C Rowe
- Department of Molecular Imaging & Therapy, Centre for PET, Austin Health, Melbourne, Australia; Department of Medicine, The University of Melbourne, Melbourne, Australia
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24
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Lunven L, Bonnet H, Yahiaoui S, Yi W, Da Costa L, Peuchmaur M, Boumendjel A, Chierici S. Disruption of Fibers from the Tau Model AcPHF6 by Naturally Occurring Aurones and Synthetic Analogues. ACS Chem Neurosci 2016; 7:995-1003. [PMID: 27225823 DOI: 10.1021/acschemneuro.6b00102] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The formation of tau aggregates is strongly linked to the neurodegenerative process in tauopathies such as Alzheimer's disease (AD). Yet only a few molecules have shown to efficiently prevent the in vitro formation of those aggregates, and the identification of such molecules is still an ongoing interest in a therapeutic context. Herein, we report the in vitro evaluation of a series of aurones against the fibrillation of the tau-derived hexapeptide AcPHF6 model. Using thioflavin T-based fluorescence assays, circular dichroism and atomic force microscopy, we showed that aurones are capable of efficiently interacting with the tau-derived hexapeptide. Importantly, this work reveals a significant activity observed for polyhydroxylated aurones. In particular, aurone 23 displayed an almost complete inhibition of fibers formation as shown by AFM at a peptide/inhibitor 1:1 ratio. It is similar to that observed for myricetin, a polyphenolic compound, well-known to prevent the in vitro elongation of tau fibers. Moreover, a tetrahydroxylated isomer, compound 24, was shown as a chemical probe of fibers rather than an inhibitor. Consequently, these results highlight aurones as a new promising scaffold to interfere with tau aggregation for both treatment and diagnosis of AD.
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Affiliation(s)
- Laurent Lunven
- Université Grenoble-Alpes, Grenoble F-38041, France
- Centre National de la Recherche Scientifique (CNRS), UMR 5250, Département
de Chimie Moléculaire, 38041 Grenoble, France
- Centre National de la Recherche
Scientifique (CNRS), UMR 5063, Département de Pharmacochimie
Moléculaire, 38400 St Martin d'Heres, France
| | - Hugues Bonnet
- Université Grenoble-Alpes, Grenoble F-38041, France
- Centre National de la Recherche Scientifique (CNRS), UMR 5250, Département
de Chimie Moléculaire, 38041 Grenoble, France
| | - Samir Yahiaoui
- Université Grenoble-Alpes, Grenoble F-38041, France
- Centre National de la Recherche
Scientifique (CNRS), UMR 5063, Département de Pharmacochimie
Moléculaire, 38400 St Martin d'Heres, France
| | - Wei Yi
- Université Grenoble-Alpes, Grenoble F-38041, France
- Centre National de la Recherche
Scientifique (CNRS), UMR 5063, Département de Pharmacochimie
Moléculaire, 38400 St Martin d'Heres, France
| | - Laurène Da Costa
- Université Grenoble-Alpes, Grenoble F-38041, France
- Centre National de la Recherche
Scientifique (CNRS), UMR 5063, Département de Pharmacochimie
Moléculaire, 38400 St Martin d'Heres, France
| | - Marine Peuchmaur
- Université Grenoble-Alpes, Grenoble F-38041, France
- Centre National de la Recherche
Scientifique (CNRS), UMR 5063, Département de Pharmacochimie
Moléculaire, 38400 St Martin d'Heres, France
| | - Ahcène Boumendjel
- Université Grenoble-Alpes, Grenoble F-38041, France
- Centre National de la Recherche
Scientifique (CNRS), UMR 5063, Département de Pharmacochimie
Moléculaire, 38400 St Martin d'Heres, France
| | - Sabine Chierici
- Université Grenoble-Alpes, Grenoble F-38041, France
- Centre National de la Recherche Scientifique (CNRS), UMR 5250, Département
de Chimie Moléculaire, 38041 Grenoble, France
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25
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Insight into the Molecular Imaging of Alzheimer's Disease. Int J Biomed Imaging 2016; 2016:7462014. [PMID: 26880871 PMCID: PMC4736963 DOI: 10.1155/2016/7462014] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2015] [Accepted: 12/16/2015] [Indexed: 12/13/2022] Open
Abstract
Alzheimer's disease is a complex neurodegenerative disease affecting millions of individuals worldwide. Earlier it was diagnosed only via clinical assessments and confirmed by postmortem brain histopathology. The development of validated biomarkers for Alzheimer's disease has given impetus to improve diagnostics and accelerate the development of new therapies. Functional imaging like positron emission tomography (PET), single photon emission computed tomography (SPECT), functional magnetic resonance imaging (fMRI), and proton magnetic resonance spectroscopy provides a means of detecting and characterising the regional changes in brain blood flow, metabolism, and receptor binding sites that are associated with Alzheimer's disease. Multimodal neuroimaging techniques have indicated changes in brain structure and metabolic activity, and an array of neurochemical variations that are associated with neurodegenerative diseases. Radiotracer-based PET and SPECT potentially provide sensitive, accurate methods for the early detection of disease. This paper presents a review of neuroimaging modalities like PET, SPECT, and selected imaging biomarkers/tracers used for the early diagnosis of AD. Neuroimaging with such biomarkers and tracers could achieve a much higher diagnostic accuracy for AD and related disorders in the future.
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26
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Villemagne VL, Okamura N. Tau imaging in the study of ageing, Alzheimer's disease, and other neurodegenerative conditions. Curr Opin Neurobiol 2015; 36:43-51. [PMID: 26397020 DOI: 10.1016/j.conb.2015.09.002] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2015] [Revised: 09/01/2015] [Accepted: 09/06/2015] [Indexed: 12/13/2022]
Abstract
In vivo tau imaging allows a deeper understanding of tau deposition in the brain, providing insights into the causes, diagnosis and treatment of primary and secondary tauopathies such as Alzheimer's disease, progressive supranuclear palsy, corticobasal syndrome, chronic traumatic encephalopathy, and some variants of frontotemporal lobar degeneration. The cross-sectional and longitudinal assessment of the temporal and spatial patterns of tau deposition in the brain will allow a better understanding of the role tau plays in ageing as well as its relationship with cognition, genotype, and neurodegeneration. It is likely that selective tau imaging could be used as a diagnostic and prognostic biomarker of disease progression, as well as a surrogate marker for monitoring of efficacy and patient recruitment for disease-specific therapeutic trials.
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Affiliation(s)
- Victor L Villemagne
- Department of Nuclear Medicine and Centre for PET, Austin Health, Victoria 3084, Australia; Department of Medicine, The University of Melbourne, Austin Health, Victoria 3084, Australia; The Florey Institute, The University of Melbourne, Victoria 3010, Australia.
| | - Nobuyuki Okamura
- Department of Pharmacology, Tohoku University School of Medicine, Sendai 980-8575, Japan
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27
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Matsumura K, Ono M, Kitada A, Watanabe H, Yoshimura M, Iikuni S, Kimura H, Okamoto Y, Ihara M, Saji H. Structure–Activity Relationship Study of Heterocyclic Phenylethenyl and Pyridinylethenyl Derivatives as Tau-Imaging Agents That Selectively Detect Neurofibrillary Tangles in Alzheimer’s Disease Brains. J Med Chem 2015; 58:7241-57. [DOI: 10.1021/acs.jmedchem.5b00440] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Kenji Matsumura
- 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
| | - Ayane Kitada
- 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
| | - Masashi Yoshimura
- 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
| | - Hiroyuki Kimura
- Department
of Patho-Functional Bioanalysis, Graduate School of Pharmaceutical
Sciences, Kyoto University, 46-29 Yoshida Shimoadachi-cho, Sakyo-ku, Kyoto 606-8501, Japan
| | - Yoko Okamoto
- Department
of Pathology, National Cerebral and Cardiovascular Center, 5-7-1 Fujishiro-dai, Suita, Osaka 565-8565, 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
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28
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Chu W, Zhou D, Gaba V, Liu J, Li S, Peng X, Xu J, Dhavale D, Bagchi DP, d'Avignon A, Shakerdge NB, Bacskai BJ, Tu Z, Kotzbauer PT, Mach RH. Design, Synthesis, and Characterization of 3-(Benzylidene)indolin-2-one Derivatives as Ligands for α-Synuclein Fibrils. J Med Chem 2015; 58:6002-17. [PMID: 26177091 DOI: 10.1021/acs.jmedchem.5b00571] [Citation(s) in RCA: 83] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
A series of 3-(benzylidine)indolin-2-one derivatives were synthesized and evaluated for their in vitro binding to alpha synuclein (α-syn), beta amyloid (Aβ), and tau fibrils. Compounds with a single double bond in the 3-position had only a modest affinity for α-syn and no selectivity for α-syn versus Aβ or tau fibrils. Homologation to the corresponding diene analogues yielded a mixture of Z,E and E,E isomers; substitution of the indoline nitrogen with an N-benzyl group resulted in increased binding to α-syn and reasonable selectivity for α-syn versus Aβ and tau. Introduction of a para-nitro group into the benzene ring of the diene enabled separation of the Z,E and E,E isomers and led to the identification of the Z,E configuration as the more active regioisomer. The data described here provide key structural information in the design of probes which bind preferentially to α-syn versus Aβ or tau fibrils.
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Affiliation(s)
- Wenhua Chu
- †Department of Radiology, Washington University School of Medicine, St. Louis, Missouri 63110, United States
| | - Dong Zhou
- †Department of Radiology, Washington University School of Medicine, St. Louis, Missouri 63110, United States
| | - Vrinda Gaba
- ‡Department of Neurology, Washington University School of Medicine, St. Louis, Missouri 63110, United States
| | - Jialu Liu
- ‡Department of Neurology, Washington University School of Medicine, St. Louis, Missouri 63110, United States
| | - Shihong Li
- †Department of Radiology, Washington University School of Medicine, St. Louis, Missouri 63110, United States
| | - Xin Peng
- †Department of Radiology, Washington University School of Medicine, St. Louis, Missouri 63110, United States
| | - Jinbin Xu
- †Department of Radiology, Washington University School of Medicine, St. Louis, Missouri 63110, United States
| | - Dhruva Dhavale
- ‡Department of Neurology, Washington University School of Medicine, St. Louis, Missouri 63110, United States
| | - Devika P Bagchi
- ‡Department of Neurology, Washington University School of Medicine, St. Louis, Missouri 63110, United States
| | - André d'Avignon
- §Department of Chemistry, Washington University, St. Louis, Missouri 63130, United States
| | - Naomi B Shakerdge
- ∥MassGeneral Institute of Neurodegenerative Disease, Massachusetts General Hospital, Charlestown, Massachusetts 02129, United States
| | - Brian J Bacskai
- ∥MassGeneral Institute of Neurodegenerative Disease, Massachusetts General Hospital, Charlestown, Massachusetts 02129, United States
| | - Zhude Tu
- †Department of Radiology, Washington University School of Medicine, St. Louis, Missouri 63110, United States
| | - Paul T Kotzbauer
- ‡Department of Neurology, Washington University School of Medicine, St. Louis, Missouri 63110, United States
| | - Robert H Mach
- †Department of Radiology, Washington University School of Medicine, St. Louis, Missouri 63110, United States.,∥MassGeneral Institute of Neurodegenerative Disease, Massachusetts General Hospital, Charlestown, Massachusetts 02129, United States
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Karakani AM, Riazi G, Mahmood Ghaffari S, Ahmadian S, Mokhtari F, Jalili Firuzi M, Zahra Bathaie S. Inhibitory effect of corcin on aggregation of 1N/4R human tau protein in vitro. IRANIAN JOURNAL OF BASIC MEDICAL SCIENCES 2015; 18:485-92. [PMID: 26124935 PMCID: PMC4475657] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/27/2014] [Accepted: 12/02/2014] [Indexed: 11/23/2022]
Abstract
OBJECTIVES Alzheimer's disease (AD) is the most common age-related neurodegenerative disorder. One of the hallmarks of AD is an abnormal accumulation of fibril forms of tau protein which is known as a microtubule associated protein. In this regard, inhibition of tau aggregation has been documented to be a potent therapeutic approach in AD and tauopathies. Unfortunately, the available synthetic drugs have modest beneficial efficacy with several side effects. Therefore, pipeline drugs from natural sources with anti-aggregation properties can be useful in the prevention and treatment of AD. Among medicinal plants, saffron (Crocus sativus, L.), as a traditional herbal medicine has different pharmacological properties and can be used as treatment for several nervous system impairment including depression and dementia. Crocin as a major constituent of saffron is the glycosylated form of crocetin. MATERIALS AND METHODS In this study, we investigated the inhibitory effect of crocin on aggregation of recombinant human tau protein 1N/4R isoform using biochemical methods and cell culture. RESULTS Results revealed that tau protein under the fibrillation condition and in the presence of crocin had enough stability with low tendency for aggregation. Crocin inhibited tau aggregation with IC50 of 100 µg/ml. Furthermore, transmission electron microscopy images confirmed that crocin could suppress the formation of tau protein filaments. CONCLUSION Inhibitory effect of crocin could be related to its interference with nucleation phase that led to increases in monomer species of tau protein. Based on our results, crocin is recommended as a proper candidate to be used in AD treatment.
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Affiliation(s)
| | - Gholamhossein Riazi
- Institute of Biochemistry and Biophysics, University of Tehran, Tehran, Iran,*Corresponding author: Gholam Hossein Riazi. Department of Biochemistry, Institute of Biochemistry and Biophysics, University of Tehran, Tehran, Iran. Tel: +98-21-61112473; Fax: +98-21-66404680;
| | | | - Shahin Ahmadian
- Institute of Biochemistry and Biophysics, University of Tehran, Tehran, Iran
| | - Farzad Mokhtari
- Institute of Biochemistry and Biophysics, University of Tehran, Tehran, Iran
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Abstract
The military conflicts of the last decade have highlighted the growing problem of traumatic brain injury in combatants returning from the battlefield. The considerable evidence pointing at the accumulation of tau aggregates and its recognition as a risk factor in neurodegenerative conditions such as Alzheimer's disease have led to a major effort to develop selective tau ligands that would allow research into the physiopathologic underpinnings of traumatic brain injury and chronic traumatic encephalopathy in military personnel and the civilian population. These tracers will allow new insights into tau pathology in the human brain, facilitating research into causes, diagnosis, and treatment of traumatic encephalopathy and major neurodegenerative dementias, such as Alzheimer's disease and some variants of frontotemporal lobar degeneration, in which tau plays a role. The field of selective tau imaging has to overcome several obstacles, some of them associated with the idiosyncrasies of tau aggregation and others related to radiotracer design. A worldwide effort has focused on the development of imaging agents that will allow selective tau imaging in vivo. Recent progress in the development of these tracers is enabling the noninvasive assessment of the extent of tau pathology in the brain, eventually allowing the quantification of changes in tau pathology over time and its relation to cognitive performance, brain volumetrics, and other biomarkers, as well as assessment of efficacy and patient recruitment for antitau therapeutic trials.
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Affiliation(s)
- Victor L Villemagne
- Department of Nuclear Medicine and Centre for PET, Austin Health, Melbourne, VIC, Australia; The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Melbourne, VIC, Australia.
| | - Nobuyuki Okamura
- Department of Pharmacology, Tohoku University School of Medicine, Sendai, Japan
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Watanabe H, Ono M, Saji H. Novel PET/SPECT probes for imaging of tau in Alzheimer's disease. ScientificWorldJournal 2015; 2015:124192. [PMID: 25879047 PMCID: PMC4386695 DOI: 10.1155/2015/124192] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2014] [Revised: 09/10/2014] [Accepted: 09/30/2014] [Indexed: 12/22/2022] Open
Abstract
As the world's population ages, the number of patients with Alzheimer's disease (AD) is predicted to increase rapidly. The presence of neurofibrillary tangles (NFTs), composed of hyperphosphorylated tau protein, is one of the neuropathological hallmarks of AD brain. Since the presence of NFTs is well correlated with neurodegeneration and cognitive decline in AD, imaging of tau using positron emission tomography (PET) and single-photon emission computed tomography (SPECT) is useful for presymptomatic diagnosis and monitoring of the progression of AD. Therefore, novel PET/SPECT probes for the imaging of tau have been developed. More recently, several probes were tested clinically and evaluated for their utility. This paper reviews the current state of research on the development and evaluation of PET/SPECT probes for the imaging of tau in AD brain.
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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
| | - 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
| | - 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
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32
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Ariza M, Kolb HC, Moechars D, Rombouts F, Andrés JI. Tau Positron Emission Tomography (PET) Imaging: Past, Present, and Future. J Med Chem 2015; 58:4365-82. [DOI: 10.1021/jm5017544] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Manuela Ariza
- Neuroscience Medicinal Chemistry, Janssen Research and Development, a Division of Janssen Pharmaceutica NV, Turnhoutseweg 30, B-2340 Beerse, Belgium
| | - Hartmuth C. Kolb
- Neuroscience Biomarkers, Janssen Research and Development, 3210 Merryfield Row, San Diego, California 92121, United States
| | - Dieder Moechars
- Neuroscience Discovery Biology, Janssen Research and Development, a Division of Janssen Pharmaceutica NV, Turnhoutseweg 30, B-2340 Beerse, Belgium
| | - Frederik Rombouts
- Neuroscience Medicinal Chemistry, Janssen Research and Development, a Division of Janssen Pharmaceutica NV, Turnhoutseweg 30, B-2340 Beerse, Belgium
| | - José Ignacio Andrés
- Discovery Sciences, Janssen Research and Development, a Division of Janssen-Cilag, Jarama 75, 45007 Toledo, Spain
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33
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Yoshimi T, Kawabata S, Taira S, Okuno A, Mikawa R, Murayama S, Tanaka K, Takikawa O. Affinity imaging mass spectrometry (AIMS): high-throughput screening for specific small molecule interactions with frozen tissue sections. Analyst 2015; 140:7202-8. [DOI: 10.1039/c5an01381j] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A novel screening system, called affinity imaging mass spectrometry (AIMS), identifies candidate small molecules with specific affinity for nanoscale structures, including proteins, in unfixed human tissue sections.
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Affiliation(s)
- T. Yoshimi
- Laboratory of Radiation Safety
- National Center for Geriatrics and Gerontology (NCGG)
- Obu
- Japan
| | - S. Kawabata
- Koichi Tanaka Mass Spectrometry Research Laboratory
- Shimadzu Corporation
- Kyoto 604-8511
- Japan
| | - S. Taira
- Faculty of Biotechnology
- Fukui Prefectural University
- Eiheiji
- Japan
| | - A. Okuno
- Laboratory of Radiation Safety
- National Center for Geriatrics and Gerontology (NCGG)
- Obu
- Japan
| | - R. Mikawa
- Laboratory of Radiation Safety
- National Center for Geriatrics and Gerontology (NCGG)
- Obu
- Japan
| | - S. Murayama
- Departments of Neurology and Neuropathology (Brain Bank for Aging Research)
- Tokyo Metropolitan Geriatric Hospital and Institute of Gerontology
- Tokyo 173-0015
- Japan
| | - K. Tanaka
- Koichi Tanaka Mass Spectrometry Research Laboratory
- Shimadzu Corporation
- Kyoto 604-8511
- Japan
| | - O. Takikawa
- Laboratory of Radiation Safety
- National Center for Geriatrics and Gerontology (NCGG)
- Obu
- Japan
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34
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Dehdashti SJ, Zheng W, Gever JR, Wilhelm R, Nguyen DT, Sittampalam G, McKew JC, Austin CP, Prusiner SB. A high-throughput screening assay for determining cellular levels of total tau protein. Curr Alzheimer Res 2014; 10:679-87. [PMID: 23905996 DOI: 10.2174/15672050113109990143] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2012] [Accepted: 07/18/2013] [Indexed: 12/20/2022]
Abstract
The microtubule-associated protein (MAP) tau has been implicated in the pathology of numerous neurodegenerative diseases. In the past decade, the hyperphosphorylated and aggregated states of tau protein have been important targets in the drug discovery field for the potential treatment of Alzheimer's disease. Although several compounds have been reported to reduce the hyperphosphorylated state of tau or impact the stabilization of tau, their therapeutic activities are remain to be validated. Recently, reduction of total cellular tau protein has emerged as an alternate intervention point for drug development and a potential treatment of tauopathies. We have developed and optimized homogenous assays, using the AlphaLISA and HTRF assay technologies, for the quantification of total cellular tau protein levels in the SH-SY5Y neuroblastoma cell line. The signal-to-basal ratios were 375 and 5.3, and the Z' factors were 0.67 and 0.60 for the AlphaLISA and HTRF tau assays, respectively. The clear advantages of these homogeneous tau assays over conventional total tau assays, such as ELISA and Western blot, are the elimination of plate wash steps and miniaturization of the assay into 1536-well plate format for the ultra-high-throughput screening of large compound libraries.
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Affiliation(s)
- Seameen J Dehdashti
- National Center for Advancing Translational Sciences, NIH, 9800 Medical Center Drive, MSC: 3370, Bethesda, MD 20892-3370, USA
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35
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Schafer KN, Cisek K, Huseby CJ, Chang E, Kuret J. Structural determinants of Tau aggregation inhibitor potency. J Biol Chem 2013; 288:32599-32611. [PMID: 24072703 DOI: 10.1074/jbc.m113.503474] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Small-molecule Tau aggregation inhibitors are under investigation as potential therapeutic agents against Alzheimer disease. Many such inhibitors have been identified in vitro, but their potency-driving features, and their molecular targets in the Tau aggregation pathway, have resisted identification. Previously we proposed ligand polarizability, a measure of electron delocalization, as a candidate descriptor of inhibitor potency. Here we tested this hypothesis by correlating the ground state polarizabilities of cyanine, phenothiazine, and arylmethine derivatives calculated using ab initio quantum methods with inhibitory potency values determined in the presence of octadecyl sulfate inducer under reducing conditions. A series of rhodanine analogs was analyzed as well using potency values disclosed in the literature. Results showed that polarizability and inhibitory potency directly correlated within all four series. To identify putative binding targets, representative members of the four chemotypes were added to aggregation reactions, where they were found to stabilize soluble, but SDS-resistant Tau species at the expense of filamentous aggregates. Using SDS resistance as a secondary assay, and a library of Tau deletion and missense mutants as targets, interaction with cyanine was localized to the microtubule binding repeat region. Moreover, the SDS-resistant phenotype was completely dependent on the presence of octadecyl sulfate inducer, but not intact PHF6/PH6* hexapeptide motifs, indicating that cyanine interacted with a species in the aggregation pathway prior to nucleus formation. Together the data suggest that flat, highly polarizable ligands inhibit Tau aggregation by interacting with folded species in the aggregation pathway and driving their assembly into soluble but highly stable Tau oligomers.
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Affiliation(s)
- Kelsey N Schafer
- From the Department of Molecular and Cellular Biochemistry, College of Medicine, The Ohio State University, Columbus, Ohio 43210
| | - Katryna Cisek
- From the Department of Molecular and Cellular Biochemistry, College of Medicine, The Ohio State University, Columbus, Ohio 43210
| | - Carol J Huseby
- From the Department of Molecular and Cellular Biochemistry, College of Medicine, The Ohio State University, Columbus, Ohio 43210
| | - Edward Chang
- From the Department of Molecular and Cellular Biochemistry, College of Medicine, The Ohio State University, Columbus, Ohio 43210
| | - Jeff Kuret
- From the Department of Molecular and Cellular Biochemistry, College of Medicine, The Ohio State University, Columbus, Ohio 43210.
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36
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Xia CF, Arteaga J, Chen G, Gangadharmath U, Gomez LF, Kasi D, Lam C, Liang Q, Liu C, Mocharla VP, Mu F, Sinha A, Su H, Szardenings AK, Walsh JC, Wang E, Yu C, Zhang W, Zhao T, Kolb HC. [18
F]T807, a novel tau positron emission tomography imaging agent for Alzheimer's disease. Alzheimers Dement 2013; 9:666-76. [DOI: 10.1016/j.jalz.2012.11.008] [Citation(s) in RCA: 448] [Impact Index Per Article: 40.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2012] [Revised: 10/26/2012] [Accepted: 11/21/2012] [Indexed: 11/15/2022]
Affiliation(s)
- Chun-Fang Xia
- Molecular Imaging Biomarker Research; Siemens Medical Solution USA, Inc; Culver City CA USA
| | - Janna Arteaga
- Molecular Imaging Biomarker Research; Siemens Medical Solution USA, Inc; Culver City CA USA
| | - Gang Chen
- Molecular Imaging Biomarker Research; Siemens Medical Solution USA, Inc; Culver City CA USA
| | - Umesh Gangadharmath
- Molecular Imaging Biomarker Research; Siemens Medical Solution USA, Inc; Culver City CA USA
| | - Luis F. Gomez
- Molecular Imaging Biomarker Research; Siemens Medical Solution USA, Inc; Culver City CA USA
| | - Dhanalakshmi Kasi
- Molecular Imaging Biomarker Research; Siemens Medical Solution USA, Inc; Culver City CA USA
| | - Chung Lam
- Molecular Imaging Biomarker Research; Siemens Medical Solution USA, Inc; Culver City CA USA
| | - Qianwa Liang
- Molecular Imaging Biomarker Research; Siemens Medical Solution USA, Inc; Culver City CA USA
| | - Changhui Liu
- Molecular Imaging Biomarker Research; Siemens Medical Solution USA, Inc; Culver City CA USA
| | - Vani P. Mocharla
- Molecular Imaging Biomarker Research; Siemens Medical Solution USA, Inc; Culver City CA USA
| | - Fanrong Mu
- Molecular Imaging Biomarker Research; Siemens Medical Solution USA, Inc; Culver City CA USA
| | - Anjana Sinha
- Molecular Imaging Biomarker Research; Siemens Medical Solution USA, Inc; Culver City CA USA
| | - Helen Su
- Molecular Imaging Biomarker Research; Siemens Medical Solution USA, Inc; Culver City CA USA
| | - A. Katrin Szardenings
- Molecular Imaging Biomarker Research; Siemens Medical Solution USA, Inc; Culver City CA USA
| | - Joseph C. Walsh
- Molecular Imaging Biomarker Research; Siemens Medical Solution USA, Inc; Culver City CA USA
| | - Eric Wang
- Molecular Imaging Biomarker Research; Siemens Medical Solution USA, Inc; Culver City CA USA
| | - Chul Yu
- Molecular Imaging Biomarker Research; Siemens Medical Solution USA, Inc; Culver City CA USA
| | - Wei Zhang
- Molecular Imaging Biomarker Research; Siemens Medical Solution USA, Inc; Culver City CA USA
| | - Tieming Zhao
- Molecular Imaging Biomarker Research; Siemens Medical Solution USA, Inc; Culver City CA USA
| | - Hartmuth C. Kolb
- Molecular Imaging Biomarker Research; Siemens Medical Solution USA, Inc; Culver City CA USA
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37
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Benadiba M, Luurtsema G, Wichert-Ana L, Buchpigel CA, Filho GB. New Molecular Targets for PET and SPECT Imaging in Neurodegenerative Diseases. BRAZILIAN JOURNAL OF PSYCHIATRY 2012; 34 Suppl 2:S125-36. [DOI: 10.1016/j.rbp.2012.07.002] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2011] [Accepted: 02/29/2012] [Indexed: 01/23/2023]
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38
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Cisek K, Jensen JR, Honson NS, Schafer KN, Cooper GL, Kuret J. Ligand electronic properties modulate tau filament binding site density. Biophys Chem 2012; 170:25-33. [PMID: 23072817 DOI: 10.1016/j.bpc.2012.09.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2012] [Revised: 09/05/2012] [Accepted: 09/06/2012] [Indexed: 10/27/2022]
Abstract
Small molecules that bind tau-bearing neurofibrillary lesions are being sought for premortem diagnosis, staging, and treatment of Alzheimer's disease and other tauopathic neurodegenerative diseases. The utility of these agents will depend on both their binding affinity and binding site density (B(max)). Previously we identified polarizability as a descriptor of protein aggregate binding affinity. To examine its contribution to binding site density, we investigated the ability of two closely related benzothiazole derivatives ((E)-2-[[4-(dimethylamino)phenyl]azo]-6-methoxybenzothiazole) and ((E)-2-[2-[4-(dimethylamino)phenyl]ethenyl]-6-methoxybenzothiazole) that differed in polarizability to displace probes of high (Thioflavin S) and low (radiolabeled (E,E)-1-iodo-2,5-bis(3-hydroxycarbonyl-4-methoxy)styrylbenzene; IMSB) density sites. Consistent with their site densities, Thioflavin S completely displaced radiolabeled IMSB, but IMSB was incapable of displacing Thioflavin S. Although both benzothiazoles displaced the low B(max) IMSB probe, only the highly polarizable analog displaced near saturating concentrations of the Thioflavin S probe. Quantum calculations showed that high polarizability reflected extensive pi-electron delocalization fostered by the presence of electron donating and accepting groups. These data suggest that electron delocalization promotes ligand binding at a subset of sites on tau aggregates that are present at high density, and that optimizing this aspect of ligand structure can yield tau-directed agents with superior diagnostic and therapeutic performance.
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Affiliation(s)
- Katryna Cisek
- Department of Molecular and Cellular Biochemistry, The Ohio State University College of Medicine, Columbus, OH 43210, USA
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39
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Synthesis and biological evaluation of novel oxindole derivatives for imaging neurofibrillary tangles in Alzheimer’s disease. Bioorg Med Chem Lett 2012; 22:5700-3. [DOI: 10.1016/j.bmcl.2012.06.086] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2012] [Revised: 06/19/2012] [Accepted: 06/26/2012] [Indexed: 11/23/2022]
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40
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Villemagne VL, Furumoto S, Fodero-Tavoletti M, Harada R, Mulligan RS, Kudo Y, Masters CL, Yanai K, Rowe CC, Okamura N. The challenges of tau imaging. FUTURE NEUROLOGY 2012. [DOI: 10.2217/fnl.12.34] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
In vivo imaging of tau pathology will provide new insights into tau deposition in the human brain, thus facilitating research into causes, diagnosis and treatment of major dementias, such as Alzheimer’s disease, or some variants of frontotemporal lobar degeneration, in which tau plays a role. Tau imaging poses several challenges, some related to the singularities of tau aggregation, and others related to radiotracer design. Several groups around the world are working on the development of imaging agents that will allow the in vivo assessment of tau deposition in aging and in neurodegeneration. Development of a tau imaging tracer will enable researchers to noninvasively examine the degree and extent of tau pathology in the brain, quantify changes in tau deposition over time, evaluate its relation to cognition and assess the efficacy of anti-tau therapy.
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Affiliation(s)
- Victor L Villemagne
- Department of Nuclear Medicine & Centre for PET, Austin Health, 145 Studley Road, Heidelberg, VIC 3084, Melbourne, Australia
| | - Shozo Furumoto
- Department of Pharmacology, Tohoku University School of Medicine, Sendai, Japan
| | | | - Ryuichi Harada
- Department of Pharmacology, Tohoku University School of Medicine, Sendai, Japan
| | - Rachel S Mulligan
- Department of Nuclear Medicine & Centre for PET, Austin Health, 145 Studley Road, Heidelberg, VIC 3084, Melbourne, Australia
| | - Yukitsuka Kudo
- Innovation of New Biomedical Engineering Center, Tohoku University, Sendai, Japan
| | | | - Kazuhiko Yanai
- Department of Pharmacology, Tohoku University School of Medicine, Sendai, Japan
| | - Chistopher C Rowe
- Department of Nuclear Medicine & Centre for PET, Austin Health, 145 Studley Road, Heidelberg, VIC 3084, Melbourne, Australia
| | - Nobuyuki Okamura
- Department of Pharmacology, Tohoku University School of Medicine, Sendai, Japan
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Yu L, Cui J, Padakanti PK, Engel L, Bagchi DP, Kotzbauer PT, Tu Z. Synthesis and in vitro evaluation of α-synuclein ligands. Bioorg Med Chem 2012; 20:4625-34. [PMID: 22789706 DOI: 10.1016/j.bmc.2012.06.023] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2012] [Revised: 06/05/2012] [Accepted: 06/12/2012] [Indexed: 11/29/2022]
Abstract
Accumulation of misfolded α-synuclein in Lewy bodies and Lewy neurites is the pathological hallmark of Parkinson's disease (PD). To identify ligands having high binding potency toward aggregated α-synuclein, we synthesized a series of phenothiazine derivatives and assessed their binding affinity to recombinant α-synuclein fibrils using a fluorescent thioflavin T competition assay. Among 16 new analogues, the in vitro data suggest that compound 11b has high affinity to α-synuclein fibrils (K(i)=32.10 ± 1.25 nM) and compounds 11d, 16a and16b have moderate affinity to α-synuclein fibrils (K(i)≈50-100 nM). Further optimization of the structure of these analogues may yield compounds with high affinity and selectivity for aggregated α-synuclein.
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Affiliation(s)
- Lihai Yu
- Department of Radiology, Washington University School of Medicine, 510 South Kingshighway Boulevard, St. Louis, MO 63110, USA
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42
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Rutin inhibits β-amyloid aggregation and cytotoxicity, attenuates oxidative stress, and decreases the production of nitric oxide and proinflammatory cytokines. Neurotoxicology 2012; 33:482-90. [PMID: 22445961 DOI: 10.1016/j.neuro.2012.03.003] [Citation(s) in RCA: 140] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2011] [Revised: 01/15/2012] [Accepted: 03/07/2012] [Indexed: 01/12/2023]
Abstract
Alzheimer's disease (AD) is a complex, multi-factorial neurodegenerative disease. The aggregation of soluble β-amyloid (Aβ) into fibrillar deposits is a pathological hallmark of AD. The Aβ aggregate-induced neurotoxicity, inflammatory reactions, oxidative stress, and nitric oxide (NO) generation are strongly linked to the etiology of AD. Here, we show that the common dietary flavonoid, rutin, can dose-dependently inhibit Aβ42 fibrillization and attenuate Aβ42-induced cytotoxicity in SH-SY5Y neuroblastoma cells. Moreover, rutin decreases the formation of reactive oxygen species (ROS), NO, glutathione disulfide (GSSG), and malondialdehyde (MDA), reduces inducible nitric oxide synthase (iNOS) activity, attenuates mitochondrial damage, increases the glutathione (GSH)/GSSG ratio, enhances the activities of super oxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx), and modulates the production of proinflammatory cytokines by decreasing TNF-α and IL-1β generation in microglia. Taken together, the actions of rutin on multiple pathogenic factors deserves further investigation for the prevention and treatment of AD.
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43
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Rosales-Corral SA, Acuña-Castroviejo D, Coto-Montes A, Boga JA, Manchester LC, Fuentes-Broto L, Korkmaz A, Ma S, Tan DX, Reiter RJ. Alzheimer's disease: pathological mechanisms and the beneficial role of melatonin. J Pineal Res 2012; 52:167-202. [PMID: 22107053 DOI: 10.1111/j.1600-079x.2011.00937.x] [Citation(s) in RCA: 210] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Alzheimer's disease (AD) is a highly complex neurodegenerative disorder of the aged that has multiple factors which contribute to its etiology in terms of initiation and progression. This review summarizes these diverse aspects of this form of dementia. Several hypotheses, often with overlapping features, have been formulated to explain this debilitating condition. Perhaps the best-known hypothesis to explain AD is that which involves the role of the accumulation of amyloid-β peptide in the brain. Other theories that have been invoked to explain AD and summarized in this review include the cholinergic hypothesis, the role of neuroinflammation, the calcium hypothesis, the insulin resistance hypothesis, and the association of AD with peroxidation of brain lipids. In addition to summarizing each of the theories that have been used to explain the structural neural changes and the pathophysiology of AD, the potential role of melatonin in influencing each of the theoretical processes involved is discussed. Melatonin is an endogenously produced and multifunctioning molecule that could theoretically intervene at any of a number of sites to abate the changes associated with the development of AD. Production of this indoleamine diminishes with increasing age, coincident with the onset of AD. In addition to its potent antioxidant and anti-inflammatory activities, melatonin has a multitude of other functions that could assist in explaining each of the hypotheses summarized above. The intent of this review is to stimulate interest in melatonin as a potentially useful agent in attenuating and/or delaying AD.
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Affiliation(s)
- Sergio A Rosales-Corral
- Centro de Investigación Biomédica de Occidente del Instituto Mexicano del Seguro Social, Guadalajara, Jalisco, México.
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44
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QSAR studies for prediction of cross-β sheet aggregate binding affinity and selectivity. Bioorg Med Chem 2012; 20:1434-41. [PMID: 22285571 DOI: 10.1016/j.bmc.2011.12.062] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2011] [Revised: 12/21/2011] [Accepted: 12/31/2011] [Indexed: 11/23/2022]
Abstract
Protein aggregates that accumulate in neurodegenerative diseases are important targets of radiotracer discovery efforts. Although multiple scaffold classes have been reported to bind cross-β sheet structure, their mechanism of binding and their ability to interact selectively with aggregates of varying protein composition are not well understood. Here we take a ligand-based quantitative structure-activity relationship approach to identify descriptors of binding affinity and selectivity for a series of 50 closely related benzothiazole derivatives reported to displace Thioflavin T fluorescent probe from synthetic aggregates composed of β-amyloid peptide and insulin. Using a two-step workflow involving both partial least squares and multiple linear regression methods, compound polarizability and hydrophobicity were identified as tunable mediators of binding selectivity. The correlations also revealed how polarizability could be modulated in neutral compounds having push-pull character. These data suggest that the relative affinity of small molecules for binding sites exposed on aggregate surfaces can be modulated by simple chemical design considerations that are compatible with multiple scaffolds.
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45
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Ono M, Saji H. Molecular Approaches to the Treatment, Prophylaxis, and Diagnosis of Alzheimer’s Disease: Novel PET/SPECT Imaging Probes for Diagnosis of Alzheimer’s Disease. J Pharmacol Sci 2012; 118:338-44. [DOI: 10.1254/jphs.11r08fm] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022] Open
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Buell AK, Esbjörner EK, Riss PJ, White DA, Aigbirhio FI, Toth G, Welland ME, Dobson CM, Knowles TPJ. Probing small molecule binding to amyloid fibrils. Phys Chem Chem Phys 2011; 13:20044-52. [PMID: 22006124 DOI: 10.1039/c1cp22283j] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Much effort has focussed in recent years on probing the interactions of small molecules with amyloid fibrils and other protein aggregates. Understanding and control of such interactions are important for the development of diagnostic and therapeutic strategies in situations where protein aggregation is associated with disease. In this perspective article we give an overview over the toolbox of biophysical methods for the study of such amyloid-small molecule interactions. We discuss in detail two recently developed techniques within this framework: linear dichroism, a promising extension of the more traditional spectroscopic techniques, and biosensing methods, where surface-bound amyloid fibrils are exposed to solutions of small molecules. Both techniques rely on the measurement of physical properties that are very directly linked to the binding of small molecules to amyloid aggregates and therefore provide an attractive route to probe these important interactions.
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Affiliation(s)
- Alexander K Buell
- Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, UK
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Jensen JR, Cisek K, Honson NS, Kuret J. Ligand polarizability contributes to tau fibril binding affinity. Bioorg Med Chem 2011; 19:5147-54. [PMID: 21803586 DOI: 10.1016/j.bmc.2011.07.016] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2011] [Revised: 07/07/2011] [Accepted: 07/11/2011] [Indexed: 10/18/2022]
Abstract
Whole brain imaging of tau-bearing neurofibrillary lesions has the potential to improve the premortem diagnosis and staging of Alzheimer's disease. Diverse compounds with high affinity for tau aggregates have been reported from high-throughput screens, but the affinity driving features common among them have not been determined. To identify these features, analogs of compounds discovered by high-throughput screening, including phenothiazine, triarylmethine, benzothiazole, and oxindole derivatives, were tested for their ability to displace fluorescent thioflavin dyes from filaments made from recombinant tau protein or authentic paired helical filaments purified from Alzheimer's disease tissue. When representative members of all scaffolds were assayed, the rank order of binding affinity determined for synthetic and authentic filaments correlated strongly, indicating that synthetic filaments have predictive utility for ligand development. Within individual scaffold families, binding affinity was found to correlate with compound polarizability, consistent with a role for dispersion forces in mediating ligand binding. Overall, the data indicate that polarizability is an important commonality among structurally diverse tau binding ligands, and that affinity for tau aggregates can be maximized by integrating formal assessment of this parameter into ligand discovery efforts.
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Affiliation(s)
- Jordan R Jensen
- Department of Molecular and Cellular Biochemistry, The Ohio State University College of Medicine, Columbus, OH 43210, USA
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Matsumura K, Ono M, Hayashi S, Kimura H, Okamoto Y, Ihara M, Takahashi R, Mori H, Saji H. Phenyldiazenyl benzothiazole derivatives as probes for in vivo imaging of neurofibrillary tangles in Alzheimer's disease brains. MEDCHEMCOMM 2011. [DOI: 10.1039/c1md00034a] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Vernon AC, Ballard C, Modo M. Neuroimaging for Lewy body disease: is the in vivo molecular imaging of α-synuclein neuropathology required and feasible? ACTA ACUST UNITED AC 2010; 65:28-55. [PMID: 20685363 DOI: 10.1016/j.brainresrev.2010.05.006] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2009] [Revised: 05/26/2010] [Accepted: 05/26/2010] [Indexed: 12/21/2022]
Abstract
Alpha-synuclein aggregation is a neuropathological hallmark of many neurodegenerative diseases including Parkinson's disease (PD), Parkinson's disease with dementia (PDD) and dementia with Lewy bodies (DLB), collectively termed the α-synucleinopathies. Substantial advances in clinical criteria and neuroimaging technology over the last 20 years have allowed great strides in the detection and differential diagnosis of these disorders. Nevertheless, it is clear that whilst the array of different imaging modalities in clinical use allow for a robust diagnosis of α-synucleinopathy in comparison to healthy subjects, there is no clear diagnostic imaging marker that affords a reliable differential diagnosis between the different forms of Lewy body disease (LBD) or that could facilitate tracking of disease progression. This has led to a call for a biomarker based on the pathological hallmarks of these diseases, namely α-synuclein-positive Lewy bodies (LBs). This potentially may be advantageous in terms of early disease detection, but may also be leveraged into a potential marker of disease progression. We here aim to firstly review the current status of neuroimaging biomarkers in PD and related synucleinopathies. Secondly, we outline the rationale behind α-synuclein imaging as a potential novel biomarker as well as the potential benefits and limitations of this approach. Thirdly, we attempt to illustrate the likely technical hurdles to be overcome to permit successful in vivo imaging of α-synuclein pathology in the diseased brain. Our overriding aim is to provide a framework for discussion of how to address this major unmet clinical need.
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Affiliation(s)
- Anthony C Vernon
- Kings College London, Institute of Psychiatry, Department of Neuroscience, Denmark Hill campus, London, UK
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Chang E, Honson NS, Bandyopadhyay B, Funk KE, Jensen JR, Kim S, Naphade S, Kuret J. Modulation and detection of tau aggregation with small-molecule ligands. Curr Alzheimer Res 2009; 6:409-14. [PMID: 19874263 DOI: 10.2174/156720509789207976] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2008] [Accepted: 01/16/2009] [Indexed: 11/22/2022]
Abstract
Recent results from high-throughput and other screening approaches reveal that small molecules can directly interact with recombinant full-length tau monomers and fibrillar tau aggregates in three distinct modes. First, in the high concentration regime (>10 micromolar), certain anionic molecules such as Congo red efficiently promote tau filament formation through a nucleation-elongation mechanism involving a dimeric nucleus and monomer-mediated elongation. These compounds are useful for modeling tau aggregation in vitro and in biological models. Second, in the low concentration regime (<1 micromolar), other ligands, including cyanine dyes, display aggregation antagonist activity. Compounds that can prevent or reverse fibrillization are candidate modifiers of disease pathology. Finally, certain compounds bind mature tau fibrils with varying affinities at multiple binding sites without modulating the aggregation reaction. For some ligands, >10-fold selectivity for tau aggregates relative to filaments composed of beta-amyloid or alpha-synuclein can be demonstrated at the level of binding affinity. Together these observations suggest that small-molecules have utility for interrogating the tau aggregation pathway, for inhibiting neuritic lesion formation, and for selective pre-mortem detection of neurofibrillary lesions through whole brain imaging.
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Affiliation(s)
- Edward Chang
- Center for Molecular Neurobiology, Department of Molecular and Cellular Biochemistry, The Ohio State University College of Medicine, Columbus, Ohio 43210, USA
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