1
|
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.
Collapse
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.
| |
Collapse
|
2
|
Uzuegbunam BC, Li J, Paslawski W, Weber W, Svenningsson P, Ågren H, Hooshyar Yousefi B. In Silico and In Vitro Study towards the Rational Design of 4,4'-Disarylbisthiazoles as a Selective α-Synucleinopathy Biomarker. Int J Mol Sci 2023; 24:16445. [PMID: 38003637 PMCID: PMC10671360 DOI: 10.3390/ijms242216445] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2023] [Revised: 11/07/2023] [Accepted: 11/10/2023] [Indexed: 11/26/2023] Open
Abstract
The α-synucleinopathies are a group of neurodegenerative diseases characterized by the deposition of α-synuclein aggregates (α-syn) in the brain. Currently, there is no suitable tracer to enable a definitive early diagnosis of these diseases. We reported candidates based on 4,4'-disarylbisthiazole (DABTA) scaffold with a high affinity towards α-syn and excellent selectivity over Aβ and tau fibrils. Based on prior in silico studies, a focused library of 23 halogen-containing and O-methylated DABTAs was prepared. The DABTAs were synthesized via a modified two-step Hantzsch thiazole synthesis, characterized, and used in competitive binding assays against [3H]PiB and [3H]DCVJ. The DABTAs were obtained with an overall chemical yield of 15-71%, and showed a calculated lipophilicity of 2.5-5.7. The ligands demonstrated an excellent affinity to α-syn with both [3H]PiB and [3H]DCVJ: Ki 0.1-4.9 nM and up to 20-3900-fold selectivity over Aβ and tau fibrils. It could be concluded that in silico simulation is useful for the rational design of a new generation of DABTAs. Further investigation of the leads in the next step is encouraged: radiolabeling of the ligands with radioisotopes such as fluorine-18 or carbon-11 for in vivo, ex vivo, and translational research and for further in vitro experiments on human-derived protein aggregates.
Collapse
Affiliation(s)
- Bright C. Uzuegbunam
- Department of Nuclear Medicine, Technical University of Munich, 81675 Munich, Germany
| | - Junhao Li
- Department of Physics and Astronomy, Uppsala University, 751 20 Uppsala, Sweden
| | - Wojciech Paslawski
- Department of Clinical Neuroscience, Karolinska Institute, 171 76 Stockholm, Sweden
| | - Wolfgang Weber
- Department of Nuclear Medicine, Technical University of Munich, 81675 Munich, Germany
| | - Per Svenningsson
- Department of Clinical Neuroscience, Karolinska Institute, 171 76 Stockholm, Sweden
| | - Hans Ågren
- Department of Physics and Astronomy, Uppsala University, 751 20 Uppsala, Sweden
| | | |
Collapse
|
3
|
Haider A, Elghazawy NH, Dawood A, Gebhard C, Wichmann T, Sippl W, Hoener M, Arenas E, Liang SH. Translational molecular imaging and drug development in Parkinson's disease. Mol Neurodegener 2023; 18:11. [PMID: 36759912 PMCID: PMC9912681 DOI: 10.1186/s13024-023-00600-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2022] [Accepted: 01/23/2023] [Indexed: 02/11/2023] Open
Abstract
Parkinson's disease (PD) is a progressive neurodegenerative disorder that primarily affects elderly people and constitutes a major source of disability worldwide. Notably, the neuropathological hallmarks of PD include nigrostriatal loss and the formation of intracellular inclusion bodies containing misfolded α-synuclein protein aggregates. Cardinal motor symptoms, which include tremor, rigidity and bradykinesia, can effectively be managed with dopaminergic therapy for years following symptom onset. Nonetheless, patients ultimately develop symptoms that no longer fully respond to dopaminergic treatment. Attempts to discover disease-modifying agents have increasingly been supported by translational molecular imaging concepts, targeting the most prominent pathological hallmark of PD, α-synuclein accumulation, as well as other molecular pathways that contribute to the pathophysiology of PD. Indeed, molecular imaging modalities such as positron emission tomography (PET) and single-photon emission computed tomography (SPECT) can be leveraged to study parkinsonism not only in animal models but also in living patients. For instance, mitochondrial dysfunction can be assessed with probes that target the mitochondrial complex I (MC-I), while nigrostriatal degeneration is typically evaluated with probes designed to non-invasively quantify dopaminergic nerve loss. In addition to dopaminergic imaging, serotonin transporter and N-methyl-D-aspartate (NMDA) receptor probes are increasingly used as research tools to better understand the complexity of neurotransmitter dysregulation in PD. Non-invasive quantification of neuroinflammatory processes is mainly conducted by targeting the translocator protein 18 kDa (TSPO) on activated microglia using established imaging agents. Despite the overwhelming involvement of the brain and brainstem, the pathophysiology of PD is not restricted to the central nervous system (CNS). In fact, PD also affects various peripheral organs such as the heart and gastrointestinal tract - primarily via autonomic dysfunction. As such, research into peripheral biomarkers has taken advantage of cardiac autonomic denervation in PD, allowing the differential diagnosis between PD and multiple system atrophy with probes that visualize sympathetic nerve terminals in the myocardium. Further, α-synuclein has recently gained attention as a potential peripheral biomarker in PD. This review discusses breakthrough discoveries that have led to the contemporary molecular concepts of PD pathophysiology and how they can be harnessed to develop effective imaging probes and therapeutic agents. Further, we will shed light on potential future trends, thereby focusing on potential novel diagnostic tracers and disease-modifying therapeutic interventions.
Collapse
Affiliation(s)
- Ahmed Haider
- Department of Radiology, Division of Nuclear Medicine and Molecular Imaging Massachusetts General Hospital and Harvard Medical School, 55 Fruit Street, Boston, MA 02114 USA
- Department of Radiology and Imaging Sciences, Emory University, 101 Woodruff Circle, Atlanta, GA 30322 USA
| | - Nehal H. Elghazawy
- Biochemistry Department, Faculty of Pharmacy and Biotechnology, German University in Cairo, Main Entrance of Al-Tagamoa Al-Khames, Cairo, 11835 Egypt
- Molecular Genetics Research Team (MGRT), Pharmaceutical Biology Department, Faculty of Pharmacy and Biotechnology, German University in Cairo, Main Entrance of Al-Tagamoa Al-Khames, Cairo, 11835 Egypt
| | - Alyaa Dawood
- Biochemistry Department, Faculty of Pharmacy and Biotechnology, German University in Cairo, Main Entrance of Al-Tagamoa Al-Khames, Cairo, 11835 Egypt
- Molecular Genetics Research Team (MGRT), Pharmaceutical Biology Department, Faculty of Pharmacy and Biotechnology, German University in Cairo, Main Entrance of Al-Tagamoa Al-Khames, Cairo, 11835 Egypt
| | - Catherine Gebhard
- Department of Nuclear Medicine, University Hospital Zurich, Raemistrasse 100, 8091 Zurich, Switzerland
- Center for Molecular Cardiology, University of Zurich, Schlieren, Switzerland
| | - Thomas Wichmann
- Department of Neurology/School of Medicine, Yerkes National Primate Research Center, Emory University, Atlanta, GA USA
| | - Wolfgang Sippl
- Institute of Pharmacy, Department of Medicinal Chemistry, Martin-Luther-University Halle-Wittenberg, W.-Langenbeck-Str. 4, 06120 Halle, Germany
| | - Marius Hoener
- Neuroscience and Rare Diseases Discovery and Translational Area, Roche Innovation Center Basel, F. Hoffmann-La Roche, Grenzacherstrasse 124, 4070 Basel, Switzerland
| | - Ernest Arenas
- Karolinska Institutet, MBB, Molecular Neurobiology, Stockholm, Sweden
| | - Steven H. Liang
- Department of Radiology, Division of Nuclear Medicine and Molecular Imaging Massachusetts General Hospital and Harvard Medical School, 55 Fruit Street, Boston, MA 02114 USA
- Department of Radiology and Imaging Sciences, Emory University, 101 Woodruff Circle, Atlanta, GA 30322 USA
| |
Collapse
|
4
|
Wang Q, Zhong J, Li K, Wu J, Wang X, Jiang S, Dai J, Cheng Y. Compact Luminol Chemiluminophores for In Vivo Detection and Imaging of β-Sheet Protein Aggregates. Anal Chem 2023; 95:1065-1073. [PMID: 36542087 DOI: 10.1021/acs.analchem.2c03776] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Protein aggregation has been found in a wide range of neurodegenerative protein-misfolding diseases. The demand for in vivo technologies to identify protein aggregation is at the leading edge for the pathogenic study, diagnostic development, and therapeutic intervention of these devastating disorders. Herein, we report a series of luminol analogues to construct a facile chemiluminescence (CL)-based approach for in vivo detection and imaging of β-sheet protein aggregates. The synthesized compounds exhibited a distinct chemiluminescent response with long emission wavelengths toward reactive oxygen species under physiological conditions and displayed signal amplification in the presence of β-sheet protein aggregates, including α-synuclein, β-amyloid, and tau. Among them, CyLumi-3 was further evaluated as a chemiluminescent probe in preclinical models. By intravenous administration into the model mice via the tail vein, in vivo CL imaging noninvasively detected the specific CL of the probe targeting the α-synuclein aggregates in the brains of living mice. Based on its structural characteristics, CyLumi-3 can readily interact with α-synuclein aggregates with significantly enhanced fluorescence and can identify α-synuclein aggregates in vivo via distinctive CL amplification, which could pave the way for a more comprehensive understanding of protein aggregation in preclinical studies and would provide new hints for developing small-molecule chemiluminophores for protein aggregates.
Collapse
Affiliation(s)
- Qinyu Wang
- 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 610041, China
| | - Jing Zhong
- 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 610041, China
| | - Kexin 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 610041, China
| | - Jiajun Wu
- 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 610041, China
| | - Xiaoxue Wang
- 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 610041, China
| | - Shen 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 610041, China
| | - Jiapei Dai
- Wuhan Institute for Neuroscience and Neuroengineering, South-Central University for Nationalities, Wuhan 430074, China
| | - 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 610041, China
| |
Collapse
|
5
|
Nwabufo CK, Aigbogun OP. Diagnostic and therapeutic agents that target alpha-synuclein in Parkinson's disease. J Neurol 2022; 269:5762-5786. [PMID: 35831620 PMCID: PMC9281355 DOI: 10.1007/s00415-022-11267-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2022] [Revised: 06/29/2022] [Accepted: 07/01/2022] [Indexed: 12/14/2022]
Abstract
The development of disease-modifying drugs and differential diagnostic agents is an urgent medical need in Parkinson’s disease. Despite the complex pathophysiological pathway, the misfolding of alpha-synuclein has been identified as a putative biomarker for detecting the onset and progression of the neurodegeneration associated with Parkinson’s disease. Identifying the most appropriate alpha-synuclein-based diagnostic modality with clinical translation will revolutionize the diagnosis of Parkinson’s. Likewise, molecules that target alpha-synuclein could alter the disease pathway that leads to Parkinson’s and may serve as first-in class therapeutics compared to existing treatment options such as levodopa and dopamine agonist that do not necessarily modify the disease pathway. Notwithstanding the promising benefits that alpha-synuclein presents to therapeutics and diagnostics development for Parkinson’s disease, finding ways to address potential challenges such as inadequate preclinical models, safety and efficacy will be paramount to achieving clinical translation. In this comprehensive review paper, we described the role of alpha-synuclein in the pathogenesis of Parkinson’s disease, as well as how its structure and function relationship delineate disease onset and progression. We further discussed different alpha-synuclein-based diagnostic modalities including biomolecular assays and molecular imaging. Finally, we presented current small molecules and biologics that are being developed as disease-modifying drugs or positron emission tomography imaging probes for Parkinson’s disease.
Collapse
Affiliation(s)
- Chukwunonso K Nwabufo
- Drug Discovery and Development Research Group, College of Pharmacy and Nutrition, University of Saskatchewan, Saskatoon, Canada. .,Department of Pharmaceutical Sciences, Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, ON, M5S 3M2, Canada.
| | - Omozojie P Aigbogun
- Drug Discovery and Development Research Group, College of Pharmacy and Nutrition, University of Saskatchewan, Saskatoon, Canada.,Department of Chemistry, University of Saskatchewan, Saskatoon, Canada
| |
Collapse
|
6
|
Structure-specific amyloid precipitation in biofluids. Nat Chem 2022; 14:1045-1053. [PMID: 35798951 DOI: 10.1038/s41557-022-00976-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Accepted: 05/16/2022] [Indexed: 11/08/2022]
Abstract
The composition of soluble toxic protein aggregates formed in vivo is currently unknown in neurodegenerative diseases, due to their ultra-low concentration in human biofluids and their high degree of heterogeneity. Here we report a method to capture amyloid-containing aggregates in human biofluids in an unbiased way, a process we name amyloid precipitation. We use a structure-specific chemical dimer, a Y-shaped, bio-inspired small molecule with two capture groups, for amyloid precipitation to increase affinity. Our capture molecule for amyloid precipitation (CAP-1) consists of a derivative of Pittsburgh Compound B (dimer) to target the cross β-sheets of amyloids and a biotin moiety for surface immobilization. By coupling CAP-1 to magnetic beads, we demonstrate that we can target the amyloid structure of all protein aggregates present in human cerebrospinal fluid, isolate them for analysis and then characterize them using single-molecule fluorescence imaging and mass spectrometry. Amyloid precipitation enables unbiased determination of the molecular composition and structural features of the in vivo aggregates formed in neurodegenerative diseases.
Collapse
|
7
|
Raval NR, Nasser A, Madsen CA, Beschorner N, Beaman EE, Juhl M, Lehel S, Palner M, Svarer C, Plavén-Sigray P, Jørgensen LM, Knudsen GM. An in vivo Pig Model for Testing Novel Positron Emission Tomography Radioligands Targeting Cerebral Protein Aggregates. Front Neurosci 2022; 16:847074. [PMID: 35368260 PMCID: PMC8966485 DOI: 10.3389/fnins.2022.847074] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2022] [Accepted: 01/31/2022] [Indexed: 12/11/2022] Open
Abstract
Positron emission tomography (PET) has become an essential clinical tool for diagnosing neurodegenerative diseases with abnormal accumulation of proteins like amyloid-β or tau. Despite many attempts, it has not been possible to develop an appropriate radioligand for imaging aggregated α-synuclein in the brain for diagnosing, e.g., Parkinson’s Disease. Access to a large animal model with α-synuclein pathology would critically enable a more translationally appropriate evaluation of novel radioligands. We here establish a pig model with cerebral injections of α-synuclein preformed fibrils or brain homogenate from postmortem human brain tissue from individuals with Alzheimer’s disease (AD) or dementia with Lewy body (DLB) into the pig’s brain, using minimally invasive surgery and validated against saline injections. In the absence of a suitable α-synuclein radioligand, we validated the model with the unselective amyloid-β tracer [11C]PIB, which has a high affinity for β-sheet structures in aggregates. Gadolinium-enhanced MRI confirmed that the blood-brain barrier was intact. A few hours post-injection, pigs were PET scanned with [11C]PIB. Quantification was done with Logan invasive graphical analysis and simplified reference tissue model 2 using the occipital cortex as a reference region. After the scan, we retrieved the brains to confirm successful injection using autoradiography and immunohistochemistry. We found four times higher [11C]PIB uptake in AD-homogenate-injected regions and two times higher uptake in regions injected with α-synuclein-preformed-fibrils compared to saline. The [11C]PIB uptake was the same in non-injected (occipital cortex, cerebellum) and injected (DLB-homogenate, saline) regions. With its large brain and ability to undergo repeated PET scans as well as neurosurgical procedures, the pig provides a robust, cost-effective, and good translational model for assessment of novel radioligands including, but not limited to, proteinopathies.
Collapse
Affiliation(s)
- Nakul Ravi Raval
- Neurobiology Research Unit, Copenhagen University Hospital (Rigshospitalet), Copenhagen, Denmark
- Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Arafat Nasser
- Neurobiology Research Unit, Copenhagen University Hospital (Rigshospitalet), Copenhagen, Denmark
| | - Clara Aabye Madsen
- Neurobiology Research Unit, Copenhagen University Hospital (Rigshospitalet), Copenhagen, Denmark
- Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Natalie Beschorner
- Center for Translational Neuromedicine, University of Copenhagen, Copenhagen, Denmark
| | - Emily Eufaula Beaman
- Neurobiology Research Unit, Copenhagen University Hospital (Rigshospitalet), Copenhagen, Denmark
| | - Morten Juhl
- Cardiology Stem Cell Centre, Copenhagen University Hospital (Rigshospitalet), Copenhagen, Denmark
| | - Szabolcs Lehel
- Department of Clinical Physiology, Nuclear Medicine and Positron Emission Tomography (PET), Copenhagen University Hospital (Rigshospitalet), Copenhagen, Denmark
| | - Mikael Palner
- Neurobiology Research Unit, Copenhagen University Hospital (Rigshospitalet), Copenhagen, Denmark
- Department of Clinical Research, Clinical Physiology and Nuclear Medicine, University of Southern Denmark, Odense, Denmark
- Department of Nuclear Medicine, Odense University Hospital, Odense, Denmark
| | - Claus Svarer
- Neurobiology Research Unit, Copenhagen University Hospital (Rigshospitalet), Copenhagen, Denmark
| | - Pontus Plavén-Sigray
- Neurobiology Research Unit, Copenhagen University Hospital (Rigshospitalet), Copenhagen, Denmark
| | - Louise Møller Jørgensen
- Neurobiology Research Unit, Copenhagen University Hospital (Rigshospitalet), Copenhagen, Denmark
- Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- Copenhagen Spine Research Unit, Copenhagen University Hospital (Rigshospitalet), Glostrup, Denmark
| | - Gitte Moos Knudsen
- Neurobiology Research Unit, Copenhagen University Hospital (Rigshospitalet), Copenhagen, Denmark
- Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- *Correspondence: Gitte Moos Knudsen,
| |
Collapse
|
8
|
Alzghool OM, van Dongen G, van de Giessen E, Schoonmade L, Beaino W. α-Synuclein Radiotracer Development and In Vivo Imaging: Recent Advancements and New Perspectives. Mov Disord 2022; 37:936-948. [PMID: 35289424 PMCID: PMC9310945 DOI: 10.1002/mds.28984] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2021] [Revised: 02/14/2022] [Accepted: 02/21/2022] [Indexed: 12/13/2022] Open
Abstract
α-Synucleinopathies including idiopathic Parkinson's disease, dementia with Lewy bodies and multiple systems atrophy share overlapping symptoms and pathological hallmarks. Selective neurodegeneration and Lewy pathology are the main hallmarks of α-synucleinopathies. Currently, there is no imaging biomarker suitable for a definitive early diagnosis of α-synucleinopathies. Although dopaminergic deficits detected with single-photon emission computed tomography (SPECT) and positron emission tomography (PET) radiotracers can support clinical diagnosis by confirming the presence of dopaminergic neurodegeneration, dopaminergic imaging cannot visualize the preceding disease process, nor distinguish α-synucleinopathies from tauopathies with dopaminergic neurodegeneration, especially at early symptomatic disease stage when clinical presentation is often overlapping. Aggregated α-synuclein (αSyn) could be a suitable imaging biomarker in α-synucleinopathies, because αSyn aggregation and therefore, Lewy pathology is evidently an early driver of α-synucleinopathies pathogenesis. Additionally, several antibodies and small molecule compounds targeting aggregated αSyn are in development for therapy. However, there is no way to directly measure if or how much they lower the levels of aggregated αSyn in the brain. There is clearly a paramount diagnostic and therapeutic unmet medical need. To date, aggregated αSyn and Lewy pathology inclusion bodies cannot be assessed ante-mortem with SPECT or PET imaging because of the suboptimal binding characteristics and/or physicochemical properties of current radiotracers. The aim of this narrative review is to highlight the suitability of aggregated αSyn as an imaging biomarker in α-synucleinopathies, the current limitations with and lessons learned from αSyn radiotracer development, and finally to propose antibody-based ligands for imaging αSyn aggregates as a complementary tool rather than an alternative to small molecule ligands. © 2022 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson Movement Disorder Society.
Collapse
Affiliation(s)
- Obada M Alzghool
- Department of Radiology and Nuclear Medicine, Tracer Center Amsterdam, Amsterdam UMC, Vrije Universiteit, Amsterdam, The Netherlands.,Turku PET Centre, University of Turku, Turku, Finland
| | - Guus van Dongen
- Department of Radiology and Nuclear Medicine, Tracer Center Amsterdam, Amsterdam UMC, Vrije Universiteit, Amsterdam, The Netherlands
| | - Elsmarieke van de Giessen
- Department of Radiology and Nuclear Medicine, Tracer Center Amsterdam, Amsterdam UMC, Vrije Universiteit, Amsterdam, The Netherlands
| | - Linda Schoonmade
- Medical Library, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
| | - Wissam Beaino
- Department of Radiology and Nuclear Medicine, Tracer Center Amsterdam, Amsterdam UMC, Vrije Universiteit, Amsterdam, The Netherlands
| |
Collapse
|
9
|
Roshanbin S, Xiong M, Hultqvist G, Söderberg L, Zachrisson O, Meier S, Ekmark-Lewén S, Bergström J, Ingelsson M, Sehlin D, Syvänen S. In vivo imaging of alpha-synuclein with antibody-based PET. Neuropharmacology 2022; 208:108985. [PMID: 35149134 DOI: 10.1016/j.neuropharm.2022.108985] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2021] [Revised: 01/05/2022] [Accepted: 02/02/2022] [Indexed: 12/11/2022]
Abstract
The protein alpha-synuclein (αSYN) plays a central role in synucleinopathies such as Parkinsons's disease (PD) and multiple system atrophy (MSA). Presently, there are no selective αSYN positron emission tomography (PET) radioligands that do not also show affinity to amyloid-beta (Aβ). We have previously shown that radiolabeled antibodies, engineered to enter the brain via the transferrin receptor (TfR), is a promising approach for PET imaging of intrabrain targets. In this study, we used this strategy to visualize αSYN in the living mouse brain. Five bispecific antibodies, binding to both the murine TfR and αSYN were generated and radiolabeled with iodine-125 or iodine-124. All bispecific antibodies bound to αSYN and mTfR before and after radiolabelling in an ELISA assay, and bound to brain sections prepared from αSYN overexpressing mice as well as human PD- and MSA subjects, but not control tissues in autoradiography. Brain concentrations of the bispecific antibodies were between 26-63 times higher than the unmodified IgG format 2 h post-injection, corresponding to about 1.5% of the injected dose per gram brain tissue. Additionally, intrastriatal αSYN fibrils were visualised with PET in an αSYN deposition mouse model with one of the bispecific antibodies, [124I]RmAbSynO2-scFv8D3. However, PET images acquired in αSYN transgenic mice with verified brain pathology injected with [124I]RmAbSynO2-scFv8D3 and [124I]RmAb48-scFv8D3 showed no increase in antibody retention compared to WT mice. Despite successful imaging of deposited extracellular αSYN using a brain-penetrating antibody-based radioligand with no cross-specificity towards Aβ, this proof-of-concept study demonstrates challenges in imaging intracellular αSYN inclusions present in synucleinopathies.
Collapse
Affiliation(s)
- Sahar Roshanbin
- Department of Public Health and Caring Sciences, Uppsala University, Uppsala, Sweden.
| | - Mengfei Xiong
- Department of Public Health and Caring Sciences, Uppsala University, Uppsala, Sweden
| | - Greta Hultqvist
- Department of Pharmaceutical Biosciences, Uppsala University, Uppsala, Sweden
| | | | | | - Silvio Meier
- Department of Public Health and Caring Sciences, Uppsala University, Uppsala, Sweden
| | - Sara Ekmark-Lewén
- Department of Public Health and Caring Sciences, Uppsala University, Uppsala, Sweden
| | - Joakim Bergström
- Department of Public Health and Caring Sciences, Uppsala University, Uppsala, Sweden
| | - Martin Ingelsson
- Department of Public Health and Caring Sciences, Uppsala University, Uppsala, Sweden; Department of Medicine and Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, Canada
| | - Dag Sehlin
- Department of Public Health and Caring Sciences, Uppsala University, Uppsala, Sweden
| | - Stina Syvänen
- Department of Public Health and Caring Sciences, Uppsala University, Uppsala, Sweden
| |
Collapse
|
10
|
Pravin N, Kumar R, Tripathi S, Kumar P, Mohite GM, Navalkar A, Panigrahi R, Singh N, Gadhe LG, Manchanda S, Shimozawa M, Nilsson P, Johansson J, Kumar A, Maji SK, Shanmugam M. Benzimidazole-based fluorophores for the detection of amyloid fibrils with higher sensitivity than Thioflavin-T. J Neurochem 2020; 156:1003-1019. [PMID: 32750740 DOI: 10.1111/jnc.15138] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2019] [Revised: 07/14/2020] [Accepted: 07/28/2020] [Indexed: 12/16/2022]
Abstract
Protein aggregation into amyloid fibrils is a key feature of a multitude of neurodegenerative diseases such as Alzheimer's, Parkinson's, and Prion disease. To detect amyloid fibrils, fluorophores with high sensitivity and better efficiency coupled with the low toxicity are in high demand even to date. In this pursuit, we have unveiled two benzimidazole-based fluorescence sensors ([C15 H15 N3 ] (C1) and [C16 H16 N3 O2 ] (C2), which possess exceptional affinity toward different amyloid fibrils in its submicromolar concentration (8 × 10-9 M), whereas under a similar concentration, the gold standard Thioflavin-T (ThT) fails to bind with amyloid fibrils. These fluorescent markers bind to α-Syn amyloid fibrils as well as amyloid fibrils forming other proteins/peptides including Aβ42 amyloid fibrils. The 1 H-15 N heteronuclear quantum correlation spectroscopy nuclear magnetic resonance data collected on wild-type α-Syn monomer with and without the fluorophores (C1 and C2) reveal that there is weak or no interactions between C1 or C2 with residues in α-Syn monomer, which indirectly reflects the specific binding ability of C1 and C2 to the α-Syn amyloid fibrils. Detailed studies further suggest that C1 and C2 can detect/bind with the α-Syn amyloid fibril as low as 100 × 10-9 M. Extremely low or no cytotoxicity is observed for C1 and C2 and they do not interfere with α-Syn fibrillation kinetics, unlike ThT. Both C1/C2 not only shows selective binding with amyloid fibrils forming various proteins/peptides but also displays excellent affinity and selectivity toward α-Syn amyloid aggregates in SH-SY5Y cells and Aβ42 amyloid plaques in animal brain tissues. Overall, our data show that the developed dyes could be used for the detection of amyloid fibrils including α-Syn and Aβ42 amyloids with higher sensitivity as compared to currently used ThT.
Collapse
Affiliation(s)
- Narayanaperumal Pravin
- Department of Chemistry, Indian Institute of Technology Bombay, Mumbai, Maharashtra, India
| | - Rakesh Kumar
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Mumbai, Maharashtra, India.,Division of Neurogeriatrics, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Stockholm, Sweden
| | - Shalini Tripathi
- Department of Chemistry, Indian Institute of Technology Bombay, Mumbai, Maharashtra, India
| | - Pardeep Kumar
- Department of Chemistry, Indian Institute of Technology Bombay, Mumbai, Maharashtra, India
| | - Ganesh M Mohite
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Mumbai, Maharashtra, India
| | - Ambuja Navalkar
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Mumbai, Maharashtra, India
| | - Rajlaxmi Panigrahi
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Mumbai, Maharashtra, India
| | - Namrata Singh
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Mumbai, Maharashtra, India
| | - Laxmikant G Gadhe
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Mumbai, Maharashtra, India
| | - Shaffi Manchanda
- Division of Neurogeriatrics, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Stockholm, Sweden
| | - Makoto Shimozawa
- Division of Neurogeriatrics, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Stockholm, Sweden
| | - Per Nilsson
- Division of Neurogeriatrics, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Stockholm, Sweden
| | - Jan Johansson
- Division of Neurogeriatrics, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Stockholm, Sweden
| | - Ashutosh Kumar
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Mumbai, Maharashtra, India
| | - Samir K Maji
- Department of Biosciences and Bioengineering, Indian Institute of Technology Bombay, Mumbai, Maharashtra, India
| | - Maheswaran Shanmugam
- Department of Chemistry, Indian Institute of Technology Bombay, Mumbai, Maharashtra, India
| |
Collapse
|
11
|
Advances in the development of imaging probes and aggregation inhibitors for alpha-synuclein. Acta Pharmacol Sin 2020; 41:483-498. [PMID: 31586134 PMCID: PMC7470848 DOI: 10.1038/s41401-019-0304-y] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2019] [Accepted: 08/29/2019] [Indexed: 12/20/2022] Open
Abstract
Abnormal protein aggregation has been linked to many neurodegenerative diseases, including Parkinson’s disease (PD). The main pathological hallmark of PD is the formation of Lewy bodies (LBs) and Lewy neurites, both of which contain the presynaptic protein alpha-synuclein (α-syn). Under normal conditions, native α-syn exists in a soluble unfolded state but undergoes misfolding and aggregation into toxic aggregates under pathological conditions. Toxic α-syn species, especially oligomers, can cause oxidative stress, membrane penetration, synaptic and mitochondrial dysfunction, as well as other damage, leading to neuronal death and eventually neurodegeneration. Early diagnosis and treatments targeting PD pathogenesis are urgently needed. Given its critical role in PD, α-syn is an attractive target for the development of both diagnostic tools and effective therapeutics. This review summarizes the progress toward discovering imaging probes and aggregation inhibitors for α-syn. Relevant strategies and techniques in the discovery of α-syn-targeted drugs are also discussed.
Collapse
|
12
|
Bondia P, Torra J, Tone CM, Sawazaki T, del Valle A, Sot B, Nonell S, Kanai M, Sohma Y, Flors C. Nanoscale View of Amyloid Photodynamic Damage. J Am Chem Soc 2019; 142:922-930. [DOI: 10.1021/jacs.9b10632] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Patricia Bondia
- Madrid Institute for Advanced Studies in Nanoscience (IMDEA Nanociencia), C/Faraday 9, Madrid 28049, Spain
| | - Joaquim Torra
- Madrid Institute for Advanced Studies in Nanoscience (IMDEA Nanociencia), C/Faraday 9, Madrid 28049, Spain
| | - Caterina M. Tone
- Madrid Institute for Advanced Studies in Nanoscience (IMDEA Nanociencia), C/Faraday 9, Madrid 28049, Spain
| | - Taka Sawazaki
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Adrián del Valle
- Madrid Institute for Advanced Studies in Nanoscience (IMDEA Nanociencia), C/Faraday 9, Madrid 28049, Spain
| | - Begoña Sot
- Madrid Institute for Advanced Studies in Nanoscience (IMDEA Nanociencia), C/Faraday 9, Madrid 28049, Spain
| | - Santi Nonell
- Institut Químic de Sarrià, Universitat Ramon Llull, Via Augusta 390, Barcelona 08017, Spain
| | - Motomu Kanai
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Youhei Sohma
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Cristina Flors
- Madrid Institute for Advanced Studies in Nanoscience (IMDEA Nanociencia), C/Faraday 9, Madrid 28049, Spain
| |
Collapse
|
13
|
Beaurain M, Salabert AS, Ribeiro MJ, Arlicot N, Damier P, Le Jeune F, Demonet JF, Payoux P. Innovative Molecular Imaging for Clinical Research, Therapeutic Stratification, and Nosography in Neuroscience. Front Med (Lausanne) 2019; 6:268. [PMID: 31828073 PMCID: PMC6890558 DOI: 10.3389/fmed.2019.00268] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2019] [Accepted: 11/01/2019] [Indexed: 01/06/2023] Open
Abstract
Over the past few decades, several radiotracers have been developed for neuroimaging applications, especially in PET. Because of their low steric hindrance, PET radionuclides can be used to label molecules that are small enough to cross the blood brain barrier, without modifying their biological properties. As the use of 11C is limited by its short physical half-life (20 min), there has been an increasing focus on developing tracers labeled with 18F for clinical use. The first such tracers allowed cerebral blood flow and glucose metabolism to be measured, and the development of molecular imaging has since enabled to focus more closely on specific targets such as receptors, neurotransmitter transporters, and other proteins. Hence, PET and SPECT biomarkers have become indispensable for innovative clinical research. Currently, the treatment options for a number of pathologies, notably neurodegenerative diseases, remain only supportive and symptomatic. Treatments that slow down or reverse disease progression are therefore the subject of numerous studies, in which molecular imaging is proving to be a powerful tool. PET and SPECT biomarkers already make it possible to diagnose several neurological diseases in vivo and at preclinical stages, yielding topographic, and quantitative data about the target. As a result, they can be used for assessing patients' eligibility for new treatments, or for treatment follow-up. The aim of the present review was to map major innovative radiotracers used in neuroscience, and explain their contribution to clinical research. We categorized them according to their target: dopaminergic, cholinergic or serotoninergic systems, β-amyloid plaques, tau protein, neuroinflammation, glutamate or GABA receptors, or α-synuclein. Most neurological disorders, and indeed mental disorders, involve the dysfunction of one or more of these targets. Combinations of molecular imaging biomarkers can afford us a better understanding of the mechanisms underlying disease development over time, and contribute to early detection/screening, diagnosis, therapy delivery/monitoring, and treatment follow-up in both research and clinical settings.
Collapse
Affiliation(s)
- Marie Beaurain
- CHU de Toulouse, Toulouse, France.,ToNIC, Toulouse NeuroImaging Center, Inserm U1214, Toulouse, France
| | - Anne-Sophie Salabert
- CHU de Toulouse, Toulouse, France.,ToNIC, Toulouse NeuroImaging Center, Inserm U1214, Toulouse, France
| | - Maria Joao Ribeiro
- UMR 1253, iBrain, Université de Tours, Inserm, Tours, France.,Inserm CIC 1415, University Hospital, Tours, France.,CHRU Tours, Tours, France
| | - Nicolas Arlicot
- UMR 1253, iBrain, Université de Tours, Inserm, Tours, France.,Inserm CIC 1415, University Hospital, Tours, France.,CHRU Tours, Tours, France
| | - Philippe Damier
- Inserm U913, Neurology Department, University Hospital, Nantes, France
| | | | - Jean-François Demonet
- Leenards Memory Centre, Department of Clinical Neuroscience, Centre Hospitalier Universitaire Vaudois, Lausanne, Switzerland
| | - Pierre Payoux
- CHU de Toulouse, Toulouse, France.,ToNIC, Toulouse NeuroImaging Center, Inserm U1214, Toulouse, France
| |
Collapse
|
14
|
Näsström T, Andersson PO, Lejon C, Karlsson BCG. Amyloid fibrils prepared using an acetylated and methyl amidated peptide model of the α-Synuclein NAC 71-82 amino acid stretch contain an additional cross-β structure also found in prion proteins. Sci Rep 2019; 9:15949. [PMID: 31685848 PMCID: PMC6828723 DOI: 10.1038/s41598-019-52206-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2019] [Accepted: 10/15/2019] [Indexed: 11/09/2022] Open
Abstract
The 71-82 fragment of the non-amyloid-β component (NAC) region of the Parkinson's disease (PD) and dementia with Lewy bodies (DLB) related protein α-Synuclein, has been reported to be important during protein misfolding. Although reports have demonstrated the importance of this fragment for the aggregation properties of the full-length protein, its exact role in pre-fibrillar oligomerisation, fibrillar growth and morphology has not yet been fully elucidated. Here, we provide evidence that fibrils prepared from an acetylated and methyl amidated peptide of the NAC 71-82 amino acid stretch of α-Synuclein are amyloid and contain, in addition to the cross-β structure detected in the full-length protein fibrils, a cross-β structure previously observed in prion proteins. These results shed light on the aggregation propensity of the NAC 71-82 amino acid stretch of the full-length protein but also the roles of the N- and C-terminal domains of α-Synuclein in balancing this aggregation propensity. The results also suggest that early aggregated forms of the capped NAC 71-82 peptide generated structures were stabilised by an anti-parallel and twisted β-sheet motif. Due to its expected toxicity, this β-sheet motif may be a promising molecular target for the development of therapeutic strategies for PD and DLB.
Collapse
Affiliation(s)
- Thomas Näsström
- Neurodegenerative Disorders Unit, Linnæus University, SE-392 31, Kalmar, Sweden.
| | - Per Ola Andersson
- FOI Swedish Defence Research Agency, CBRN Defence & Security, SE-901 82, Umeå, Sweden.,Department of Engineering Sciences: Applied Material Science, Uppsala University, SE-751 21, Uppsala, Sweden
| | - Christian Lejon
- FOI Swedish Defence Research Agency, CBRN Defence & Security, SE-901 82, Umeå, Sweden
| | - Björn C G Karlsson
- Physical Pharmacy Laboratory, Linnæus University Centre for Biomaterials Chemistry, Linnæus University, SE-392 31, Kalmar, Sweden.
| |
Collapse
|
15
|
Delic V, Chandra S, Abdelmotilib H, Maltbie T, Wang S, Kem D, Scott HJ, Underwood RN, Liu Z, Volpicelli-Daley LA, West AB. Sensitivity and specificity of phospho-Ser129 α-synuclein monoclonal antibodies. J Comp Neurol 2019; 526:1978-1990. [PMID: 29888794 DOI: 10.1002/cne.24468] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2018] [Revised: 03/22/2018] [Accepted: 04/02/2018] [Indexed: 01/05/2023]
Abstract
α-Synuclein (α-syn) is an abundant presynaptic protein that is the primary constituent of inclusions that define Lewy body diseases (LBDs). In these inclusions, α-syn is phosphorylated at the serine-129 residue. Antibodies directed to this phosphorylation site are used to measure inclusion abundance and stage disease progression in preclinical models as well as in postmortem tissues in LBDs. While it is critical to reliably identify inclusions, phospho-specific antibodies often cross-react with nonspecific antigens. Four commercially available monoclonal antibodies, two from rabbits (clones EP1536Y and MJF-R13) and two from mice (81a and pSyn#64), have been the most widely used in detecting pS129-α-syn inclusions. Here, we systematically evaluated these antibodies in brain sections and protein lysates from rats and mice. All antibodies detected pS129-α-syn inclusions in the brain that were induced by preformed α-syn fibrils in wild-type rats and mice. Antibody titrations revealed that clones EP1536Y and 81a comparably labeled inclusions in both the perikarya and neuronal processes in contrast to clones MJF-R13 and pSyn#64 that incompletely labeled inclusions at various antibody concentrations. Except for EP1536Y, the clones produced nonspecific diffuse neuropil labeling in α-syn knockout mice as well as mice and rats injected with monomeric α-syn, with some nonspecific staining titrating with pS129-α-syn inclusions. By immunoblot, all the clones cross-reacted with proteins other than α-syn, warranting caution in interpretations of specificity. Clone EP1536Y uniquely and robustly detected endogenous pS129-α-syn in highly soluble protein fractions from the mouse brain. In summary, EP1536Y had the highest sensitivity and specificity for detecting pS129-α-syn.
Collapse
Affiliation(s)
- Vedad Delic
- Department of Neurology, University of Alabama at Birmingham, Birmingham, Alabama
| | - Sidhanth Chandra
- Department of Neurology, University of Alabama at Birmingham, Birmingham, Alabama
| | - Hisham Abdelmotilib
- Department of Neurology, University of Alabama at Birmingham, Birmingham, Alabama
| | - Tyler Maltbie
- Department of Neurology, University of Alabama at Birmingham, Birmingham, Alabama
| | - Shijie Wang
- Department of Neurology, University of Alabama at Birmingham, Birmingham, Alabama
| | - Danielle Kem
- Department of Neurology, University of Alabama at Birmingham, Birmingham, Alabama
| | - Hunter J Scott
- Department of Neurology, University of Alabama at Birmingham, Birmingham, Alabama
| | - Rachel N Underwood
- Department of Neurology, University of Alabama at Birmingham, Birmingham, Alabama
| | - Zhiyong Liu
- Department of Neurology, University of Alabama at Birmingham, Birmingham, Alabama
| | | | - Andrew B West
- Department of Neurology, University of Alabama at Birmingham, Birmingham, Alabama
| |
Collapse
|
16
|
Wilson H, Pagano G, Politis M. Dementia spectrum disorders: lessons learnt from decades with PET research. J Neural Transm (Vienna) 2019; 126:233-251. [PMID: 30762136 PMCID: PMC6449308 DOI: 10.1007/s00702-019-01975-4] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2018] [Accepted: 01/21/2019] [Indexed: 02/07/2023]
Abstract
The dementia spectrum encompasses a range of disorders with complex diagnosis, pathophysiology and limited treatment options. Positron emission tomography (PET) imaging provides insights into specific neurodegenerative processes underlying dementia disorders in vivo. Here we focus on some of the most common dementias: Alzheimer's disease, Parkinsonism dementias including Parkinson's disease with dementia, dementia with Lewy bodies, progressive supranuclear palsy and corticobasal syndrome, and frontotemporal lobe degeneration. PET tracers have been developed to target specific proteinopathies (amyloid, tau and α-synuclein), glucose metabolism, cholinergic system and neuroinflammation. Studies have shown distinct imaging abnormalities can be detected early, in some cases prior to symptom onset, allowing disease progression to be monitored and providing the potential to predict symptom onset. Furthermore, advances in PET imaging have identified potential therapeutic targets and novel methods to accurately discriminate between different types of dementias in vivo. There are promising imaging markers with a clinical application on the horizon, however, further studies are required before they can be implantation into clinical practice.
Collapse
Affiliation(s)
- Heather Wilson
- Neurodegeneration Imaging Group, Maurice Wohl Clinical Neuroscience Institute, 125 Coldharbour Lane, Camberwell, London, SE5 9NU, UK
| | - Gennaro Pagano
- Neurodegeneration Imaging Group, Maurice Wohl Clinical Neuroscience Institute, 125 Coldharbour Lane, Camberwell, London, SE5 9NU, UK
| | - Marios Politis
- Neurodegeneration Imaging Group, Maurice Wohl Clinical Neuroscience Institute, 125 Coldharbour Lane, Camberwell, London, SE5 9NU, UK.
| |
Collapse
|
17
|
Cifelli JL, Capule CC, Yang J. Noncovalent, Electrostatic Interactions Induce Positively Cooperative Binding of Small Molecules to Alzheimer's and Parkinson's Disease-Related Amyloids. ACS Chem Neurosci 2019; 10:991-995. [PMID: 30044911 DOI: 10.1021/acschemneuro.8b00280] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Amyloids are self-assembled protein aggregates that represent a major hallmark of many neurologic and systemic diseases. Among the common features of amyloids is the presence of a high density of multiple binding sites for small molecule ligands, making them an attractive target for design of multimeric binding agents. Here, we demonstrate that noncovalent, intermolecular interactions between a 1:1 mixture of oppositely charged benzothiazole molecules enhances their binding to two different amyloid aggregates: Alzheimer's-related amyloid-β (Aβ) peptides or Parkinson's-related α-synuclein (αS) proteins. We show that this mixture leads to positively cooperative binding to amyloid targets, with up to 10-fold enhancement of binding compared to the uncharged parent compound. The observed enhancement of amyloid binding using noncovalent interactions was similar in magnitude to a benzothiazole dimer to aggregated Aβ. These results represent a novel strategy for designing amyloid-targeting molecules with enhanced affinity, which could aid in the development of new diagnostic or treatment strategies for amyloid-associated diseases.
Collapse
Affiliation(s)
- Jessica L. Cifelli
- Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093-0358, United States
| | - Christina C. Capule
- Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093-0358, United States
| | - Jerry Yang
- Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093-0358, United States
| |
Collapse
|
18
|
Investigation of α-Synuclein Amyloid Fibrils Using the Fluorescent Probe Thioflavin T. Int J Mol Sci 2018; 19:ijms19092486. [PMID: 30142878 PMCID: PMC6163839 DOI: 10.3390/ijms19092486] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2018] [Revised: 08/08/2018] [Accepted: 08/20/2018] [Indexed: 11/29/2022] Open
Abstract
In this work, α-synuclein amyloid fibrils—the formation of which is a biomarker of Parkinson’s disease—were investigated using the fluorescent probe thioflavin T (ThT). The experimental conditions of protein fibrillogenesis were chosen so that a sufficient number of continuous measurements could be performed to characterize and analyze all stages of this process. The reproducibility of fibrillogenesis and the structure of the obtained aggregates (which is a critical point for further investigation) were proven using a wide range of physical-chemical methods. For the determination of ThT-α-synuclein amyloid fibril binding parameters, the sample and reference solutions were prepared using equilibrium microdialysis. By utilizing absorption spectroscopy of these solutions, the ThT-fibrils binding mode with a binding constant of about 104 M−1 and stoichiometry of ThT per protein molecule of about 1:8 was observed. Fluorescence spectroscopy of the same solutions with the subsequent correction of the recorded fluorescence intensity on the primary inner filter effect allowed us to determine another mode of ThT binding to fibrils, with a binding constant of about 106 M−1 and stoichiometry of about 1:2500. Analysis of the photophysical characteristics of the dye molecules bound to the sites of different binding modes allowed us to assume the possible localization of these sites. The obtained differences in the ThT binding parameters to the amyloid fibrils formed from α-synuclein and other amyloidogenic proteins, as well as in the photophysical characteristics of the bound dye, confirmed the hypothesis of amyloid fibril polymorphism.
Collapse
|
19
|
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.
Collapse
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
| |
Collapse
|
20
|
Mathis CA, Lopresti BJ, Ikonomovic MD, Klunk WE. Small-molecule PET Tracers for Imaging Proteinopathies. Semin Nucl Med 2017; 47:553-575. [PMID: 28826526 DOI: 10.1053/j.semnuclmed.2017.06.003] [Citation(s) in RCA: 77] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
In this chapter, we provide a review of the challenges and advances in developing successful PET imaging agents for 3 major types of aggregated amyloid proteins: amyloid-beta (Aβ), tau, and alpha-synuclein (α-syn). These 3 amyloids are involved in the pathogenesis of a variety of neurodegenerative diseases, referred to as proteinopathies or proteopathies, that include Alzheimer disease, Lewy body dementias, multiple system atrophy, and frontotemporal dementias, among others. In the Introduction section, we briefly discuss the history of amyloid in neurodegenerative diseases and describe why progress in developing effective imaging agents has been hampered by the failure of crystallography to provide definitive ligand-protein interactions for rational radioligand design efforts. Instead, the field has relied on largely serendipitous, trial-and-error methods to achieve useful and specific PET amyloid imaging tracers for Aβ, tau, and α-syn deposits. Because many of the proteopathies involve more than 1 amyloid protein, it is important to develop selective PET tracers for the different amyloids to help assess the relative contribution of each to total amyloid burden. We use Pittsburgh compound B to illustrate some of the critical steps in developing a potent and selective Aβ PET imaging agent. Other selective Aβ and tau PET imaging compounds have followed similar pathways in their developmental processes. Success for selective α-syn PET imaging agents has not been realized yet, but work is ongoing in multiple laboratories throughout the world. In the tau sections, we provide background regarding 3-repeat (3R) and 4-repeat (4R) tau proteins and how they can affect the binding of tau radioligands in different tauopathies. We review the ongoing efforts to assess the properties of tau ligands, which are useful in 3R, 4R, or combined 3R-4R tauopathies. Finally, we describe in the α-syn sections recent attempts to develop selective tracers to image α-synucleinopathies.
Collapse
Affiliation(s)
- Chester A Mathis
- Department of Radiology, University of Pittsburgh School of Medicine, Pittsburgh, PA.
| | - Brian J Lopresti
- Department of Radiology, University of Pittsburgh School of Medicine, Pittsburgh, PA
| | - Milos D Ikonomovic
- Department of Neurology, University of Pittsburgh School of Medicine, Pittsburgh, PA
| | - William E Klunk
- Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, PA
| |
Collapse
|
21
|
Ikonomovic MD, Buckley CJ, Heurling K, Sherwin P, Jones PA, Zanette M, Mathis CA, Klunk WE, Chakrabarty A, Ironside J, Ismail A, Smith C, Thal DR, Beach TG, Farrar G, Smith APL. Post-mortem histopathology underlying β-amyloid PET imaging following flutemetamol F 18 injection. Acta Neuropathol Commun 2016; 4:130. [PMID: 27955679 PMCID: PMC5154022 DOI: 10.1186/s40478-016-0399-z] [Citation(s) in RCA: 71] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2016] [Accepted: 11/29/2016] [Indexed: 01/19/2023] Open
Abstract
In vivo imaging of fibrillar β-amyloid deposits may assist clinical diagnosis of Alzheimer's disease (AD), aid treatment selection for patients, assist clinical trials of therapeutic drugs through subject selection, and be used as an outcome measure. A recent phase III trial of [18F]flutemetamol positron emission tomography (PET) imaging in 106 end-of-life subjects demonstrated the ability to identify fibrillar β-amyloid by comparing in vivo PET to post-mortem histopathology. Post-mortem analyses demonstrated a broad and continuous spectrum of β-amyloid pathology in AD and other dementing and non-dementing disease groups. The GE067-026 trial demonstrated 91% sensitivity and 90% specificity of [18F]flutemetamol PET by majority read for the presence of moderate or frequent plaques. The probability of an abnormal [18F]flutemetamol scan increased with neocortical plaque density and AD diagnosis. All dementia cases with non-AD neurodegenerative diseases and those without histopathological features of β-amyloid deposits were [18F]flutemetamol negative. Majority PET assessments accurately reflected the amyloid plaque burden in 90% of cases. However, ten cases demonstrated a mismatch between PET image interpretations and post-mortem findings. Although tracer retention was best associated with amyloid in neuritic plaques, amyloid in diffuse plaques and cerebral amyloid angiopathy best explain three [18F]flutemetamol positive cases with mismatched (sparse) neuritic plaque burden. Advanced cortical atrophy was associated with the seven false negative [18F]flutemetamol images. The interpretation of images from pathologically equivocal cases was associated with low reader confidence and inter-reader agreement. Our results support that amyloid in neuritic plaque burden is the primary form of β-amyloid pathology detectable with [18F]flutemetamol PET imaging. ClinicalTrials.gov NCT01165554. Registered June 21, 2010; NCT02090855. Registered March 11, 2014.
Collapse
|
22
|
Abstract
Amyloid plaques, along with neurofibrillary tangles, are a neuropathologic hallmark of Alzheimer disease (AD). Recently, amyloid PET radiotracers have been developed and approved for clinical use in the evaluation of suspected neurodegenerative disorders. In both research and clinical settings, amyloid PET imaging has provided important diagnostic and prognostic information for the management of patients with possible AD, mild cognitive impairment (MCI), and other challenging diagnostic presentations. Although the overall impact of amyloid imaging is still being evaluated, the Society of Nuclear Medicine and Molecular Imaging and Alzheimer's Association Amyloid Imaging Task Force have created appropriate use criteria for the standard clinical use of amyloid PET imaging. By the appropriate use criteria, amyloid imaging is appropriate for patients with (1) persistent or unexplained MCI, (2) AD as a possible but still uncertain diagnosis after expert evaluation and (3) atypically early-age-onset progressive dementia. To better understand the clinical and economic effect of amyloid imaging, the Imaging Dementia-Evidence for Amyloid Scanning (IDEAS) study is an ongoing large multicenter study in the United States, which is evaluating how amyloid imaging affects diagnosis, management, and outcomes for cognitively impaired patients who cannot be completely evaluated by clinical assessment alone. Multiple other large-scale studies are evaluating the prognostic role of amyloid PET imaging for predicting MCI progression to AD in general and high-risk populations. At the same time, amyloid imaging is an important tool for evaluating potential disease-modifying therapies for AD. Overall, the increased use of amyloid PET imaging has led to a better understanding of the strengths and limitations of this imaging modality and how it may best be used with other clinical, molecular, and imaging assessment techniques for the diagnosis and management of neurodegenerative disorders.
Collapse
Affiliation(s)
- Atul Mallik
- Department of Radiology and Imaging Sciences, University of Utah, Salt Lake City, UT.
| | - Alex Drzezga
- Department of Nuclear Medicine, University of Cologne, Cologne, Germany
| | - Satoshi Minoshima
- Department of Radiology and Imaging Sciences, University of Utah, Salt Lake City, UT
| |
Collapse
|
23
|
Amyloid imaging: Past, present and future perspectives. Ageing Res Rev 2016; 30:95-106. [PMID: 26827784 DOI: 10.1016/j.arr.2016.01.005] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2015] [Revised: 01/21/2016] [Accepted: 01/22/2016] [Indexed: 11/23/2022]
Abstract
Alzheimer's disease (AD) is a progressive neurodegenerative disorder characterised by the gradual onset of dementia. The pathological hallmarks of the disease are Aβ amyloid plaques, and tau neurofibrillary tangles, along dendritic and synaptic loss and reactive gliosis. Functional and molecular neuroimaging techniques such as positron emission tomography (PET) using functional and molecular tracers, in conjuction with other Aβ and tau biomarkers in CSF, are proving valuable in the differential diagnosis of AD, as well as in establishing disease prognosis. With the advent of new therapeutic strategies, there has been an increasing application of these techniques for the determination of Aβ burden in vivo in the patient selection, evaluation of target engagement and assessment of the efficacy of therapeutic approaches aimed at reducing Aβ in the brain.
Collapse
|
24
|
Sulatskaya AI, Kuznetsova IM, Belousov MV, Bondarev SA, Zhouravleva GA, Turoverov KK. Stoichiometry and Affinity of Thioflavin T Binding to Sup35p Amyloid Fibrils. PLoS One 2016; 11:e0156314. [PMID: 27228180 PMCID: PMC4882037 DOI: 10.1371/journal.pone.0156314] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2016] [Accepted: 05/12/2016] [Indexed: 11/25/2022] Open
Abstract
In this work two modes of binding of the fluorescent probe thioflavin T to yeast prion protein Sup35p amyloid fibrils were revealed by absorption spectrometry of solutions prepared by equilibrium microdialysis. These binding modes exhibited significant differences in binding affinity and stoichiometry. Moreover, the absorption spectrum and the molar extinction coefficient of the dye bound in each mode were determined. The fluorescence quantum yield of the dye bound in each mode was determined via a spectrofluorimetric study of the same solutions in which the recorded fluorescence intensity was corrected for the primary inner filter effect. As previously predicted, the existence of one of the detected binding modes may be due to the incorporation of the dye into the grooves along the fiber axis perpendicular to the β-sheets of the fibrils. It was assumed that the second type of binding with higher affinity may be due to the existence of ThT binding sites that are localized to areas where amyloid fibrils are clustered.
Collapse
Affiliation(s)
- Anna I. Sulatskaya
- Laboratory for Structural Dynamics, Stability and Folding of Proteins, Institute of Cytology, Russian Academy of Science, St. Petersburg, Tikhoretsky Ave. 4, 194064, Russia
| | - Irina M. Kuznetsova
- Laboratory for Structural Dynamics, Stability and Folding of Proteins, Institute of Cytology, Russian Academy of Science, St. Petersburg, Tikhoretsky Ave. 4, 194064, Russia
| | - Mikhail V. Belousov
- Department of Genetics and Biotechnology, Saint Petersburg State University, Saint Petersburg, Universitetskaya Emb. 7–9, 199034, Russia
| | - Stanislav A. Bondarev
- Department of Genetics and Biotechnology, Saint Petersburg State University, Saint Petersburg, Universitetskaya Emb. 7–9, 199034, Russia
- Laboratory of Amyloid Biology, Saint Petersburg State University, Saint Petersburg, 199034, Russia
| | - Galina A. Zhouravleva
- Department of Genetics and Biotechnology, Saint Petersburg State University, Saint Petersburg, Universitetskaya Emb. 7–9, 199034, Russia
- Laboratory of Amyloid Biology, Saint Petersburg State University, Saint Petersburg, 199034, Russia
| | - Konstantin K. Turoverov
- Laboratory for Structural Dynamics, Stability and Folding of Proteins, Institute of Cytology, Russian Academy of Science, St. Petersburg, Tikhoretsky Ave. 4, 194064, Russia
- Institute of Physics, Nanotechnology and Telecommunications, Peter the Great St.-Petersburg Polytechnic University, St. Petersburg, Polytechnicheskaya 29, 195251, Russia
- * E-mail:
| |
Collapse
|
25
|
Engler H, Damian A, Bentancourt C. PET and the multitracer concept in the study of neurodegenerative diseases. Dement Neuropsychol 2015; 9:343-349. [PMID: 29213983 PMCID: PMC5619316 DOI: 10.1590/1980-57642015dn94000343] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
The complexity of the pathological reactions of the brain to an aggression caused
by an internal or external noxa represents a challenge for molecular imaging.
Positron emission tomography (PET) can indicate in vivo,
anatomopathological changes involved in the development of different clinical
symptoms in patients with neurodegenerative disorders. PET and the multitracer
concept can provide information from different systems in the brain tissue
building an image of the whole disease. We present here the combination of
18F-flourodeoxyglucose (FDG) and
N-[11C-methyl]-L-deuterodeprenyl (DED), FDG and
N-[11C-methyl] 2-(4'-methylaminophenyl)-6-hydroxybenzothiazole (PIB),
PIB and L-[11C]-3'4-Dihydrophenylalanine (DOPA) and finally PIB and
[15O]H2O.
Collapse
Affiliation(s)
- Henry Engler
- MD. PhD - Uruguayan Centre of Molecular Imaging (CUDIM), Montevideo, Uruguay
| | - Andres Damian
- MD - Uruguayan Centre of Molecular Imaging (CUDIM), Montevideo, Uruguay
| | | |
Collapse
|
26
|
Leung CWT, Guo F, Hong Y, Zhao E, Kwok RTK, Leung NLC, Chen S, Vaikath NN, El-Agnaf OM, Tang Y, Gai WP, Tang BZ. Detection of oligomers and fibrils of α-synuclein by AIEgen with strong fluorescence. Chem Commun (Camb) 2015; 51:1866-9. [PMID: 25526628 DOI: 10.1039/c4cc07911f] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We report a fluorophore, TPE-TPP, with AIE characteristics which is utilized as a fluorescence probe to monitor the α-synuclein (α-Syn) fibrillation process. Compared with ThT, TPE-TPP shows a higher sensitivity in the detection of α-Syn oligomers as well as fibrils with a stronger fluorescence. The performance of TPE-TPP was evaluated using fluorescence, AFM, dot blot, and SEC.
Collapse
Affiliation(s)
- Chris Wai Tung Leung
- HKUST Shenzhen Research Institute, No. 9 Yuexing 1st RD, South Area, Hi-tech Park Nanshan, Shenzhen 518057, China.
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
27
|
Beach TG, Adler CH, Sue LI, Serrano G, Shill HA, Walker DG, Lue L, Roher AE, Dugger BN, Maarouf C, Birdsill AC, Intorcia A, Saxon-Labelle M, Pullen J, Scroggins A, Filon J, Scott S, Hoffman B, Garcia A, Caviness JN, Hentz JG, Driver-Dunckley E, Jacobson SA, Davis KJ, Belden CM, Long KE, Malek-Ahmadi M, Powell JJ, Gale LD, Nicholson LR, Caselli RJ, Woodruff BK, Rapscak SZ, Ahern GL, Shi J, Burke AD, Reiman EM, Sabbagh MN. Arizona Study of Aging and Neurodegenerative Disorders and Brain and Body Donation Program. Neuropathology 2015; 35:354-89. [PMID: 25619230 DOI: 10.1111/neup.12189] [Citation(s) in RCA: 303] [Impact Index Per Article: 33.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2014] [Accepted: 11/11/2014] [Indexed: 12/13/2022]
Abstract
The Brain and Body Donation Program (BBDP) at Banner Sun Health Research Institute (http://www.brainandbodydonationprogram.org) started in 1987 with brain-only donations and currently has banked more than 1600 brains. More than 430 whole-body donations have been received since this service was commenced in 2005. The collective academic output of the BBDP is now described as the Arizona Study of Aging and Neurodegenerative Disorders (AZSAND). Most BBDP subjects are enrolled as cognitively normal volunteers residing in the retirement communities of metropolitan Phoenix, Arizona. Specific recruitment efforts are also directed at subjects with Alzheimer's disease, Parkinson's disease and cancer. The median age at death is 82. Subjects receive standardized general medical, neurological, neuropsychological and movement disorders assessments during life and more than 90% receive full pathological examinations by medically licensed pathologists after death. The Program has been funded through a combination of internal, federal and state of Arizona grants as well as user fees and pharmaceutical industry collaborations. Subsets of the Program are utilized by the US National Institute on Aging Arizona Alzheimer's Disease Core Center and the US National Institute of Neurological Disorders and Stroke National Brain and Tissue Resource for Parkinson's Disease and Related Disorders. Substantial funding has also been received from the Michael J. Fox Foundation for Parkinson's Research. The Program has made rapid autopsy a priority, with a 3.0-hour median post-mortem interval for the entire collection. The median RNA Integrity Number (RIN) for frozen brain and body tissue is 8.9 and 7.4, respectively. More than 2500 tissue requests have been served and currently about 200 are served annually. These requests have been made by more than 400 investigators located in 32 US states and 15 countries. Tissue from the BBDP has contributed to more than 350 publications and more than 200 grant-funded projects.
Collapse
Affiliation(s)
- Thomas G Beach
- Banner Sun Health Research Institute, Sun City, Arizona, USA
| | | | - Lucia I Sue
- Banner Sun Health Research Institute, Sun City, Arizona, USA
| | - Geidy Serrano
- Banner Sun Health Research Institute, Sun City, Arizona, USA
| | - Holly A Shill
- Banner Sun Health Research Institute, Sun City, Arizona, USA
| | | | - LihFen Lue
- Banner Sun Health Research Institute, Sun City, Arizona, USA
| | - Alex E Roher
- Banner Sun Health Research Institute, Sun City, Arizona, USA
| | | | - Chera Maarouf
- Banner Sun Health Research Institute, Sun City, Arizona, USA
| | - Alex C Birdsill
- Banner Sun Health Research Institute, Sun City, Arizona, USA
| | | | | | - Joel Pullen
- Banner Sun Health Research Institute, Sun City, Arizona, USA
| | | | - Jessica Filon
- Banner Sun Health Research Institute, Sun City, Arizona, USA
| | - Sarah Scott
- Banner Sun Health Research Institute, Sun City, Arizona, USA
| | | | - Angelica Garcia
- Banner Sun Health Research Institute, Sun City, Arizona, USA
| | | | | | | | | | - Kathryn J Davis
- Banner Sun Health Research Institute, Sun City, Arizona, USA
| | | | - Kathy E Long
- Banner Sun Health Research Institute, Sun City, Arizona, USA
| | | | | | - Lisa D Gale
- Banner Sun Health Research Institute, Sun City, Arizona, USA
| | | | | | | | | | | | - Jiong Shi
- Barrow Neurological Institute, Phoenix, Arizona, USA
| | - Anna D Burke
- Banner Alzheimer Institute, Phoenix, Arizona, USA
| | | | | |
Collapse
|
28
|
Diehl-Schmid J, Onur OA, Kuhn J, Gruppe T, Drzezga A. Imaging Frontotemporal Lobar Degeneration. Curr Neurol Neurosci Rep 2014; 14:489. [DOI: 10.1007/s11910-014-0489-x] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
29
|
Shah M, Seibyl J, Cartier A, Bhatt R, Catafau AM. Molecular Imaging Insights into Neurodegeneration: Focus on α-Synuclein Radiotracers. J Nucl Med 2014; 55:1397-400. [DOI: 10.2967/jnumed.113.136515] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
|
30
|
Abstract
Development of molecular imaging agents for fibrillar β-amyloid positron-emission tomography during the past decade has brought molecular imaging of Alzheimer disease pathology into the spotlight. Large cohort studies with longitudinal follow-up in cognitively normal individuals and patients with mild cognitive impairment and Alzheimer disease indicate that β-amyloid deposition can be detected many years before the onset of symptoms with molecular imaging, and its progression can be followed longitudinally. The utility of β-amyloid PET in the differential diagnosis of Alzheimer disease is greatest when there is no pathologic overlap between 2 dementia syndromes, such as in frontotemporal lobar degeneration and Alzheimer disease. However β-amyloid PET alone may be insufficient in distinguishing dementia syndromes that commonly have overlapping β-amyloid pathology, such as dementia with Lewy bodies and vascular dementia, which represent the 2 most common dementia pathologies after Alzheimer disease. The role of molecular imaging in Alzheimer disease clinical trials is growing rapidly, especially in an era when preventive interventions are designed to eradicate the pathology targeted by molecular imaging agents.
Collapse
Affiliation(s)
- K Kantarci
- From the Department of Radiology, Mayo Clinic, Rochester, Minnesota.
| |
Collapse
|
31
|
Coogan MP, Doyle RP, Valliant JF, Babich JW, Zubieta J. Single amino acid chelate complexes of the M(CO)3 (+) core for correlating fluorescence and radioimaging studies (M = (99m) Tc or Re). J Labelled Comp Radiopharm 2014; 57:255-61. [PMID: 24395431 DOI: 10.1002/jlcr.3164] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2013] [Accepted: 10/29/2013] [Indexed: 01/03/2023]
Abstract
Single amino acid chelates (SAACs) and SAAC-like bifunctional ligands can be exploited in the design of a variety of bioconjugates for facile metallation with the M(CO)3 (+) unit with M = (99m) Tc or Re. When the donor groups of the ligand are quinolone, thiazole or other similarly conjugated heterocycles, the rhenium complexes are fluorescent, affording complementary and isostructural fluorescent probes to the radioactive (99m) Tc analogues. The versatility of the approach has been demonstrated by the preparation of bioconjugates incorporating peptides, biotin, folic acid, thymidine and vitamin B12 . In addition, the unusual photophysical properties observed for rhenium of the [bisthiazole-diamino butane-Re(CO)3 (+) ] derivative [BTBA-Re(CO)3 ](+) are discussed.
Collapse
Affiliation(s)
- Michael P Coogan
- School of Chemistry and Chemical Biology, University of Lancaster, Lancaster, LA1 4YB, UK
| | | | | | | | | |
Collapse
|
32
|
Li JY, Conforti L. Axonopathy in Huntington's disease. Exp Neurol 2013; 246:62-71. [DOI: 10.1016/j.expneurol.2012.08.010] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2011] [Revised: 06/27/2012] [Accepted: 08/11/2012] [Indexed: 02/02/2023]
|
33
|
Abstract
The use of functional imaging in neurodegenerative diseases has increased in recent years, with applications in research into the underlying pathophysiology, aiding in diagnosis, or evaluating new treatments. In Parkinson's disease (PD), these imaging methods have expanded our understanding of the disease beyond dopaminergic deficits. Moreover, functional imaging methods have described alterations in functional networks relating not only to the motor symptoms, but also to many nonmotor features of PD, such as cognitive dysfunction. From a clinical viewpoint, functional imaging methods can assist in monitoring disease progression, such as in the context of clinical trials, and holds the potential to aid in early diagnosis of PD and differentiation from other parkinsonian disorders.
Collapse
|
34
|
Bagchi DP, Yu L, Perlmutter JS, Xu J, Mach RH, Tu Z, Kotzbauer PT. Binding of the radioligand SIL23 to α-synuclein fibrils in Parkinson disease brain tissue establishes feasibility and screening approaches for developing a Parkinson disease imaging agent. PLoS One 2013; 8:e55031. [PMID: 23405108 PMCID: PMC3566091 DOI: 10.1371/journal.pone.0055031] [Citation(s) in RCA: 91] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2012] [Accepted: 12/18/2012] [Indexed: 12/11/2022] Open
Abstract
Accumulation of α-synuclein (α-syn) fibrils in Lewy bodies and Lewy neurites is the pathological hallmark of Parkinson disease (PD). Ligands that bind α-syn fibrils could be utilized as imaging agents to improve the diagnosis of PD and to monitor disease progression. However, ligands for α-syn fibrils in PD brain tissue have not been previously identified and the feasibility of quantifying α-syn fibrils in brain tissue is unknown. We report the identification of the (125)I-labeled α-syn radioligand SIL23. [(125)I]SIL23 binds α-syn fibrils in postmortem brain tissue from PD patients as well as an α-syn transgenic mouse model for PD. The density of SIL23 binding sites correlates with the level of fibrillar α-syn in PD brain tissue, and [(125)I]SIL23 binding site densities in brain tissue are sufficiently high to enable in vivo imaging with high affinity ligands. These results identify a SIL23 binding site on α-syn fibrils that is a feasible target for development of an α-syn imaging agent. The affinity of SIL23 for α-syn and its selectivity for α-syn versus Aβ and tau fibrils is not optimal for imaging fibrillar α-syn in vivo, but we show that SIL23 competitive binding assays can be used to screen additional ligands for suitable affinity and selectivity, which will accelerate the development of an α-syn imaging agent for PD.
Collapse
Affiliation(s)
- Devika P. Bagchi
- Department of Neurology, Washington University School of Medicine, St. Louis, Missouri, United States of America
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, Missouri, United States of America
- Hope Center for Neurological Disorders, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Lihai Yu
- Hope Center for Neurological Disorders, Washington University School of Medicine, St. Louis, Missouri, United States of America
- Department of Radiology, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Joel S. Perlmutter
- Department of Neurology, Washington University School of Medicine, St. Louis, Missouri, United States of America
- Hope Center for Neurological Disorders, Washington University School of Medicine, St. Louis, Missouri, United States of America
- Department of Radiology, Washington University School of Medicine, St. Louis, Missouri, United States of America
- Department of Anatomy & Neurobiology, Washington University School of Medicine, St. Louis, Missouri, United States of America
- Program in Occupational Therapy, and Washington University School of Medicine, St. Louis, Missouri, United States of America
- Program in Physical Therapy, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Jinbin Xu
- Hope Center for Neurological Disorders, Washington University School of Medicine, St. Louis, Missouri, United States of America
- Department of Radiology, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Robert H. Mach
- Hope Center for Neurological Disorders, Washington University School of Medicine, St. Louis, Missouri, United States of America
- Department of Radiology, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Zhude Tu
- Hope Center for Neurological Disorders, Washington University School of Medicine, St. Louis, Missouri, United States of America
- Department of Radiology, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Paul T. Kotzbauer
- Department of Neurology, Washington University School of Medicine, St. Louis, Missouri, United States of America
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, Missouri, United States of America
- Hope Center for Neurological Disorders, Washington University School of Medicine, St. Louis, Missouri, United States of America
| |
Collapse
|
35
|
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.
Collapse
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
| |
Collapse
|
36
|
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.
Collapse
Affiliation(s)
- Lihai Yu
- Department of Radiology, Washington University School of Medicine, 510 South Kingshighway Boulevard, St. Louis, MO 63110, USA
| | | | | | | | | | | | | |
Collapse
|
37
|
Villemagne VL, Klunk WE, Mathis CA, Rowe CC, Brooks DJ, Hyman BT, Ikonomovic MD, Ishii K, Jack CR, Jagust WJ, Johnson KA, Koeppe RA, Lowe VJ, Masters CL, Montine TJ, Morris JC, Nordberg A, Petersen RC, Reiman EM, Selkoe DJ, Sperling RA, Van Laere K, Weiner MW, Drzezga A. Aβ Imaging: feasible, pertinent, and vital to progress in Alzheimer's disease. Eur J Nucl Med Mol Imaging 2012; 39:209-19. [PMID: 22218879 PMCID: PMC3261395 DOI: 10.1007/s00259-011-2045-0] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
|
38
|
Kuznetsova IM, Sulatskaya AI, Uversky VN, Turoverov KK. A New Trend in the Experimental Methodology for the Analysis of the Thioflavin T Binding to Amyloid Fibrils. Mol Neurobiol 2012; 45:488-98. [DOI: 10.1007/s12035-012-8272-y] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2012] [Accepted: 04/17/2012] [Indexed: 11/29/2022]
|
39
|
Analyzing thioflavin T binding to amyloid fibrils by an equilibrium microdialysis-based technique. PLoS One 2012; 7:e30724. [PMID: 22383971 PMCID: PMC3286464 DOI: 10.1371/journal.pone.0030724] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2011] [Accepted: 12/27/2011] [Indexed: 11/19/2022] Open
Abstract
A new approach for the determination of the amyloid fibril – thioflavin T (ThT) binding parameters (the number of binding modes, stoichiometry, and binding constants of each mode) is proposed. This approach is based on the absorption spectroscopy determination of the concentration of free and bound to fibril dye in solutions, which are prepared by equilibrium microdialysis. Furthermore, the proposed approach allowed us, for the first time, to determine the absorption spectrum, molar extinction coefficient, and fluorescence quantum yield of the ThT bound to fibril by each binding modes. This approach is universal and can be used for determining the binding parameters of any dye interaction with a receptor, such as ANS binding to proteins in the molten globule state or to protein amorphous aggregates.
Collapse
|
40
|
Grimmer T, Alexopoulos P, Tsolakidou A, Guo LH, Henriksen G, Yousefi BH, Förstl H, Sorg C, Kurz A, Drzezga A, Perneczky R. Cerebrospinal fluid BACE1 activity and brain amyloid load in Alzheimer's disease. ScientificWorldJournal 2012; 2012:712048. [PMID: 22272179 PMCID: PMC3259508 DOI: 10.1100/2012/712048] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2011] [Accepted: 11/02/2011] [Indexed: 12/04/2022] Open
Abstract
The secretase BACE1 is fundamentally involved in the development of cerebral amyloid pathology in Alzheimer's disease (AD). It has not been studied so far to what extent BACE1 activity in cerebrospinal fluid (CSF) mirrors in vivo amyloid load in AD. We explored associations between CSF BACE1 activity and fibrillar amyloid pathology as measured by carbon-11-labelled Pittsburgh Compound B positron emission tomography ([11C]PIB PET). [11C]PIB and CSF studies were performed in 31 patients with AD. Voxel-based linear regression analysis revealed significant associations between CSF BACE1 activity and [11C]PIB tracer uptake in the bilateral parahippocampal region, the thalamus, and the pons. Our study provides evidence for a brain region-specific correlation between CSF BACE1 activity and in-vivo fibrillar amyloid pathology in AD. Associations were found in areas close to the brain ventricles, which may have important implications for the use of BACE1 in CSF as a marker for AD pathology and for antiamyloid treatment monitoring.
Collapse
Affiliation(s)
- Timo Grimmer
- Department of Psychiatry and Psychotherapy, Klinikum rechts der Isar, Technische Universität München, Ismaninger Street 22, 81675 München, Germany
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
41
|
Dugger BN, Serrano GE, Sue LI, Walker DG, Adler CH, Shill HA, Sabbagh MN, Caviness JN, Hidalgo J, Saxon-Labelle M, Chiarolanza G, Mariner M, Henry-Watson J, Beach TG. Presence of Striatal Amyloid Plaques in Parkinson's Disease Dementia Predicts Concomitant Alzheimer's Disease: Usefulness for Amyloid Imaging. JOURNAL OF PARKINSONS DISEASE 2012; 2:57-65. [PMID: 22924088 DOI: 10.3233/jpd-2012-11073] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Dementia is a frequent complication of Parkinson's disease (PD). About half of PD dementia (PDD) is hypothesized to be due to progression of the underlying Lewy body pathology into limbic regions and the cerebral cortex while the other half is thought to be due to coexistent Alzheimer's disease. Clinically, however, these are indistinguishable. The spread of amyloid plaques to the striatum has been reported to be a sensitive and specific indicator of dementia due to Alzheimer's disease (AD). The purpose of the present study was to determine if the presence of striatal plaques might also be a useful indicator of the presence of diagnostic levels of AD pathology within PD subjects. We analyzed neuropathologically-confirmed cases of PD without dementia (PDND, N = 31), PDD without AD (PDD, N = 31) and PD with dementia meeting clinicopathological criteria for AD (PDAD, N =40). The minimum diagnostic criterion for AD was defined as including a clinical history of dementia, moderate or frequent CERAD cortical neuritic plaque density and Braak neurofibrillary stage III-VI. Striatal amyloid plaque densities were determined using Campbell-Switzer and Thioflavine S stains. Striatal plaque densities were significantly higher in PDAD compared to PDD (p<0.001). The presence of striatal plaques was approximately 80% sensitive and 80% specific for predicting AD. In comparison, the presence of cerebral cortex plaques alone was highly sensitive (100%) but had poor specificity (48% to 55%). The results suggest that striatal amyloid imaging may be clinically useful for making the distinction between PDD and PDAD.
Collapse
|
42
|
Jeong K, Cho HR, Choi SH, Park Y, Chae PS. Protective effects of cleavage agents on INS-1 cells against h-IAPP-induced apoptosis. Chem Commun (Camb) 2012; 48:588-90. [DOI: 10.1039/c1cc16293d] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
43
|
Kantarci K, Lowe VJ, Boeve BF, Weigand SD, Senjem ML, Przybelski SA, Dickson DW, Parisi JE, Knopman DS, Smith GE, Ferman TJ, Petersen RC, Jack CR. Multimodality imaging characteristics of dementia with Lewy bodies. Neurobiol Aging 2011; 33:2091-105. [PMID: 22018896 DOI: 10.1016/j.neurobiolaging.2011.09.024] [Citation(s) in RCA: 136] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2011] [Revised: 09/06/2011] [Accepted: 09/16/2011] [Indexed: 12/14/2022]
Abstract
Dementia with Lewy bodies (DLB) is the second most common cause of neurodegenerative dementia after Alzheimer's disease (AD). Our objective was to determine whether the (11)C-Pittsburgh Compound-B (PiB) retention and regional hypometabolism on positron emission tomography (PET) and regional cortical atrophy on magnetic resonance imaging (MRI) are complementary in characterizing patients with DLB and differentiating them from AD. We studied age-, gender-, and education-matched patients with a clinical diagnosis of DLB (n = 21), AD (n = 21), and cognitively normal subjects (n = 42). Hippocampal atrophy, global cortical PiB retention and occipital lobe metabolism in combination distinguished DLB from AD better than any of the measurements alone (area under the receiver operating characteristic = 0.98). Five of the DLB and AD patients who underwent autopsy were distinguished through multimodality imaging. These data demonstrate that magnetic resonance imaging and PiB positron emission tomography contribute to characterizing the distinct pathological mechanisms in patients with AD compared with DLB. Occipital and posterior parietotemporal lobe hypometabolism is a distinguishing feature of DLB and this regional hypometabolic pattern is independent of the amyloid pathology.
Collapse
Affiliation(s)
- Kejal Kantarci
- Department of Radiology, Mayo Clinic, Rochester, MN 55905, USA.
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
44
|
Synthesis and in vitro evaluation of fluorinated styryl benzazoles as amyloid-probes. Bioorg Med Chem 2011; 19:7698-710. [PMID: 22078413 DOI: 10.1016/j.bmc.2011.09.065] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2011] [Revised: 09/23/2011] [Accepted: 09/28/2011] [Indexed: 11/23/2022]
Abstract
The formation of proteinaceous aggregates is a pathognomonic hallmark of several neurodegenerative disorders such as Alzheimer's and Parkinson's diseases. To date, the final diagnostic for these diseases can only be achieved by immunostaining of post-mortem brain tissues with the commonly used congo red and Thioflavin T/S amyloid-dyes. The interest in developing amyloid-avid radioprobes to be used for protein aggregates imaging by positron emission tomography has grown substantialy, due to the promise in assisting diagnosis of these disorders. To this purpose, the present work describes the synthesis and characterization of four novel fluorinated styryl benzazole derivatives 1-4 by means of the Wittig reaction, as well as their in vitro evaluation as amyloid-probing agents. All compounds were obtained as mixtures of geometric E and Z isomers, with the preferable formation of the E isomer. Photoisomerization reactions allowed for the maximization of the minor Z isomers. The authentic 1-4E/Z isomers were isolated after purification by column chromatography under dark conditions. Profiting from the fluorescence properties of the different geometric isomers of 1-4, their binding affinities towards amyloid fibrils of insulin, α-synuclein and β-amyloid peptide were also measured. These compounds share similarities with Thioflavin T, interacting specifically with fibrillary species with a red-shift in the excitation wavelengths along with an increase in the fluorescence emission intensity. Apparent binding constants were determined and ranged between 1.22 and 23.96 μM(-1). The present data suggest that the novel fluorinated styryl benzazole derivatives may prove useful for the design of (18)F-labeled amyloid radioprobes.
Collapse
|
45
|
Sulatskaya AI, Kuznetsova IM, Turoverov KK. Interaction of Thioflavin T with Amyloid Fibrils: Stoichiometry and Affinity of Dye Binding, Absorption Spectra of Bound Dye. J Phys Chem B 2011; 115:11519-24. [DOI: 10.1021/jp207118x] [Citation(s) in RCA: 83] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Affiliation(s)
- Anna I. Sulatskaya
- Laboratory of Structural Dynamics, Stability and Folding of Proteins of the Institute of Cytology, Russian Academy of Sciences, St. Petersburg 194064, Russia
| | - Irina M. Kuznetsova
- Laboratory of Structural Dynamics, Stability and Folding of Proteins of the Institute of Cytology, Russian Academy of Sciences, St. Petersburg 194064, Russia
| | - Konstantin K. Turoverov
- Laboratory of Structural Dynamics, Stability and Folding of Proteins of the Institute of Cytology, Russian Academy of Sciences, St. Petersburg 194064, Russia
| |
Collapse
|
46
|
Foster ER, Campbell MC, Burack MA, Hartlein J, Flores HP, Cairns NJ, Hershey T, Perlmutter JS. Amyloid imaging of Lewy body-associated disorders. Mov Disord 2011; 25:2516-23. [PMID: 20922808 DOI: 10.1002/mds.23393] [Citation(s) in RCA: 125] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Clinicopathologic studies of Parkinson disease dementia (PDD) and dementia with Lewy bodies (DLB) commonly reveal abnormal β-amyloid deposition in addition to diffuse Lewy bodies (α-synuclein aggregates), but the relationship among these neuropathologic features and the development of dementia in these disorders remains uncertain. The purpose of this study was to determine whether amyloid-β deposition detected by PET imaging with Pittsburgh Compound B (PIB) distinguishes clinical subtypes of Lewy body-associated disorders. Nine healthy controls, 8 PD with no cognitive impairment, 9 PD with mild cognitive impairment, 6 DLB, and 15 PDD patients underwent [(11)C]-PIB positron emission tomography imaging, clinical examination, and cognitive testing. The binding potential (BP) of PIB for predefined regions and the mean cortical BP (MCBP) were calculated for each participant. Annual longitudinal follow-up and postmortem examinations were performed on a subset of participants. Regional PIB BPs and the proportion of individuals with abnormally elevated MCBP were not significantly different across participant groups. Elevated PIB binding was associated with worse global cognitive impairment in participants with Lewy body disorders but was not associated with any other clinical or neuropsychological features, including earlier onset or faster rate of progression of cognitive impairment. These results suggest that the presence of fibrillar amyloid-β does not distinguish between clinical subtypes of Lewy body-associated disorders, although larger numbers are needed to more definitively rule out this association. Amyloid-β may modify the severity of global cognitive impairment in individuals with Lewy body-associated dementia.
Collapse
Affiliation(s)
- Erin R Foster
- Department of Neurology, Washington University School of Medicine, St Louis, MO, USA.
| | | | | | | | | | | | | | | |
Collapse
|
47
|
Grimmer T, Tholen S, Yousefi BH, Alexopoulos P, Förschler A, Förstl H, Henriksen G, Klunk WE, Mathis CA, Perneczky R, Sorg C, Kurz A, Drzezga A. Progression of cerebral amyloid load is associated with the apolipoprotein E ε4 genotype in Alzheimer's disease. Biol Psychiatry 2010; 68:879-84. [PMID: 20598287 PMCID: PMC3045041 DOI: 10.1016/j.biopsych.2010.05.013] [Citation(s) in RCA: 82] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/28/2010] [Revised: 04/16/2010] [Accepted: 05/07/2010] [Indexed: 11/26/2022]
Abstract
BACKGROUND Pittsburgh Compound B ([¹¹C] PiB) is a specific positron emission tomography (PET) marker of cerebral amyloid deposits. Only few data have been published on in vivo longitudinal changes of amyloid load in Alzheimer's disease (AD) patients, with conflicting results. Therefore, little is known about the factors that influence these changes. METHODS A group of 24 patients with probable AD diagnosed by combining established clinical criteria with an AD-typical pattern in [(18)F] fluoro-deoxy-glucose PET underwent [¹¹C] PiB-PET examinations at baseline and after 24 months. The difference of amyloid load between the two examinations and the association with clinical and neurobiological variables was examined with a regions-of-interest approach and voxel-based analyses. RESULTS Cerebral [¹¹C] PiB uptake ratio increased significantly by an annual rate of 3.92%. Although the increase occurred in all parts of the neocortex, no increase was detected in the archipallium. The increase was gene-dose-dependent (analysis of variance p = .012) to the number of apolipoprotein E ε4 alleles. Progression of dementia symptoms was correlated to the [¹¹C] PiB increase in numerous regions associated with cognition. CONCLUSIONS The results of this study indicate that a significant increase of amyloid deposition occurs in patients with AD during a relatively short interval of its clinical course. The rate of amyloid aggregation rate is closely associated with the apolipoprotein E genotype, which might be important for the evaluation of antiamyloid drug treatment effects. The present study further emphasizes the value of amyloid-plaque imaging as a marker of disease progression and as a potential surrogate marker to be used in antiamyloid drug trials.
Collapse
Affiliation(s)
- Timo Grimmer
- Department of Psychiatry and Psychotherapy, Klinikum rechts der Isar der Technischen Universität München, Munich, Federal Republic of Germany.
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
48
|
Grimmer T, Drzezga A, Kurz A. [Visualization of amyloid with positron emission tomography. Useful improvement in the diagnosis of dementia?]. DER NERVENARZT 2010; 81:602-6. [PMID: 20221742 DOI: 10.1007/s00115-010-2951-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Imaging techniques for in vivo visualization of cerebral amyloid using positron emission tomography (PET) have been tested in clinical trails over the past 5 years. Based on a selected overview of the literature including our own studies the various radiopharmaceuticals are presented and the current status of research on the validity of amyloid PET imaging as well as its suitability for early and differential diagnosis of Alzheimer's disease (AD) are described. The findings available up to now support the validity of amyloid PET imaging and suggest a possible benefit in differential diagnosis. However, there are as yet no studies with large sample sizes. The possible use for the early diagnosis of AD should be viewed critically, particularly due to the lack of treatment options.
Collapse
Affiliation(s)
- T Grimmer
- Klinik und Poliklinik für Psychiatrie und Psychotherapie, Zentrum für kognitive Störungen, Klinikum rechts der Isar der Technischen Universität München, Ismaninger Strasse 22, 81675, München, Deutschland.
| | | | | |
Collapse
|
49
|
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.
Collapse
Affiliation(s)
- Anthony C Vernon
- Kings College London, Institute of Psychiatry, Department of Neuroscience, Denmark Hill campus, London, UK
| | | | | |
Collapse
|
50
|
Abstract
The progressive nature of neurodegeneration suggests an age-dependent process that ultimately leads to synaptic failure and neuronal damage in cortical areas of the brain critical for memory and higher mental functions. The increasing age of the population in developed countries suggests that, if unchecked, these disorders will become increasingly prevalent. In the absence of specific biologic markers, direct pathologic examination of brain tissue still is the only definitive method for establishing a diagnosis of Alzheimer disease (AD) and other types of dementia. Pathologic hallmarks of AD are intracellular neurofibrillary tangles (NFT) and extracellular amyloid plaques. NFT are intraneuronal bundles of paired helical filaments mainly composed of the aggregates of an abnormally phosphorylated form of tau protein; neuritic plaques consist of dense extracellular aggregates of β-amyloid (Aβ), surrounded by reactive gliosis and dystrophic neurites. To date, all available evidence strongly supports the notion that an imbalance between the production and removal of Aβ leading to its progressive accumulation is central to the pathogenesis of AD. A growing understanding of the molecular mechanisms of Aβ formation, degradation, and neurotoxicity is being translated into new therapeutic approaches. Whereas AD is the most common cause of dementia in the elderly, postmortem studies have found dementia with Lewy Bodies and frontotemporal lobe degeneration each to account for about 20% of cases. Molecular neuroimaging techniques such as PET have been used for the in vivo assessment of molecular processes at their sites of action, permitting detection of subtle pathophysiological changes in the brain at asymptomatic stages The development of molecular imaging methods for noninvasively assessing disease-specific traits such as Aβ burden in AD is allowing early diagnosis at presymptomatic stages, more accurate differential diagnosis and, when available, the evaluation and monitoring of disease-modifying therapy.
Collapse
Affiliation(s)
- Victor L Villemagne
- Department of Nuclear Medicine and Centre for PET, Austin Health, 145 Studley Road, Heidelberg, Victoria 3084, Australia; The Mental Health Research Institute of Victoria, 135 Oak Street, Parkville, Victoria 3052, Australia; Department of Medicine, Austin Health, Victoria 3084, Australia.
| | - Christopher C Rowe
- Department of Nuclear Medicine and Centre for PET, Austin Health, 145 Studley Road, Heidelberg, Victoria 3084, Australia; Department of Medicine, Austin Health, Victoria 3084, Australia
| |
Collapse
|