1
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Kreutzer AG, Parrocha CMT, Haerianardakani S, Guaglianone G, Nguyen JT, Diab MN, Yong W, Perez-Rosendahl M, Head E, Nowick JS. Antibodies Raised Against an Aβ Oligomer Mimic Recognize Pathological Features in Alzheimer's Disease and Associated Amyloid-Disease Brain Tissue. ACS CENTRAL SCIENCE 2024; 10:104-121. [PMID: 38292607 PMCID: PMC10823522 DOI: 10.1021/acscentsci.3c00592] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/12/2023] [Revised: 11/27/2023] [Accepted: 11/27/2023] [Indexed: 02/01/2024]
Abstract
Antibodies that target the β-amyloid peptide (Aβ) and its associated assemblies are important tools in Alzheimer's disease research and have emerged as promising Alzheimer's disease therapies. This paper reports the creation and characterization of a triangular Aβ trimer mimic composed of Aβ17-36 β-hairpins and the generation and study of polyclonal antibodies raised against the Aβ trimer mimic. The Aβ trimer mimic is covalently stabilized by three disulfide bonds at the corners of the triangular trimer to create a homogeneous oligomer. Structural, biophysical, and cell-based studies demonstrate that the Aβ trimer mimic shares characteristics with oligomers of full-length Aβ. X-ray crystallography elucidates the structure of the trimer and reveals that four copies of the trimer assemble to form a dodecamer. SDS-PAGE, size exclusion chromatography, and dynamic light scattering reveal that the trimer also forms higher-order assemblies in solution. Cell-based toxicity assays show that the trimer elicits LDH release, decreases ATP levels, and activates caspase-3/7 mediated apoptosis. Immunostaining studies on brain slices from people who lived with Alzheimer's disease and people who lived with Down syndrome reveal that the polyclonal antibodies raised against the Aβ trimer mimic recognize pathological features including different types of Aβ plaques and cerebral amyloid angiopathy.
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Affiliation(s)
- Adam G. Kreutzer
- Department
of Chemistry, University of California Irvine, Irvine, California 92697, United States
| | - Chelsea Marie T. Parrocha
- Department
of Pharmaceutical Sciences, University of
California Irvine, Irvine, California 92697, United States
| | - Sepehr Haerianardakani
- Department
of Chemistry, University of California Irvine, Irvine, California 92697, United States
| | - Gretchen Guaglianone
- Department
of Chemistry, University of California Irvine, Irvine, California 92697, United States
| | - Jennifer T. Nguyen
- Department
of Pharmaceutical Sciences, University of
California Irvine, Irvine, California 92697, United States
| | - Michelle N. Diab
- Department
of Chemistry, University of California Irvine, Irvine, California 92697, United States
| | - William Yong
- Department
of Pathology and Laboratory Medicine, University
of California Irvine, Irvine, California 92697, United States
| | - Mari Perez-Rosendahl
- Department
of Pathology and Laboratory Medicine, University
of California Irvine, Irvine, California 92697, United States
| | - Elizabeth Head
- Department
of Pathology and Laboratory Medicine, University
of California Irvine, Irvine, California 92697, United States
| | - James S. Nowick
- Department
of Chemistry, University of California Irvine, Irvine, California 92697, United States
- Department
of Pharmaceutical Sciences, University of
California Irvine, Irvine, California 92697, United States
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2
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Kreutzer AG, Guaglianone G, Yoo S, Parrocha CMT, Ruttenberg SM, Malonis RJ, Tong K, Lin YF, Nguyen JT, Howitz WJ, Diab MN, Hamza IL, Lai JR, Wysocki VH, Nowick JS. Probing differences among Aβ oligomers with two triangular trimers derived from Aβ. Proc Natl Acad Sci U S A 2023; 120:e2219216120. [PMID: 37216514 PMCID: PMC10235986 DOI: 10.1073/pnas.2219216120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Accepted: 04/17/2023] [Indexed: 05/24/2023] Open
Abstract
The assembly of the β-amyloid peptide (Aβ) to form oligomers and fibrils is closely associated with the pathogenesis and progression of Alzheimer's disease. Aβ is a shape-shifting peptide capable of adopting many conformations and folds within the multitude of oligomers and fibrils the peptide forms. These properties have precluded detailed structural elucidation and biological characterization of homogeneous, well-defined Aβ oligomers. In this paper, we compare the structural, biophysical, and biological characteristics of two different covalently stabilized isomorphic trimers derived from the central and C-terminal regions Aβ. X-ray crystallography reveals the structures of the trimers and shows that each trimer forms a ball-shaped dodecamer. Solution-phase and cell-based studies demonstrate that the two trimers exhibit markedly different assembly and biological properties. One trimer forms small soluble oligomers that enter cells through endocytosis and activate capase-3/7-mediated apoptosis, while the other trimer forms large insoluble aggregates that accumulate on the outer plasma membrane and elicit cellular toxicity through an apoptosis-independent mechanism. The two trimers also exhibit different effects on the aggregation, toxicity, and cellular interaction of full-length Aβ, with one trimer showing a greater propensity to interact with Aβ than the other. The studies described in this paper indicate that the two trimers share structural, biophysical, and biological characteristics with oligomers of full-length Aβ. The varying structural, assembly, and biological characteristics of the two trimers provide a working model for how different Aβ trimers can assemble and lead to different biological effects, which may help shed light on the differences among Aβ oligomers.
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Affiliation(s)
- Adam G. Kreutzer
- Department of Chemistry, University of California Irvine, Irvine, CA92697
| | | | - Stan Yoo
- Department of Chemistry, University of California Irvine, Irvine, CA92697
| | | | | | - Ryan J. Malonis
- Department of Biochemistry, Albert Einstein College of Medicine, Bronx, NY10461
| | - Karen Tong
- Department of Biochemistry, Albert Einstein College of Medicine, Bronx, NY10461
| | - Yu-Fu Lin
- Resource for Native Mass Spectrometry Guided Structural Biology, The Ohio State University, Columbus, OH43210
| | - Jennifer T. Nguyen
- Department of Pharmaceutical Sciences, University of California Irvine, Irvine, CA92697
| | - William J. Howitz
- Department of Chemistry, University of California Irvine, Irvine, CA92697
| | - Michelle N. Diab
- Department of Chemistry, University of California Irvine, Irvine, CA92697
| | - Imane L. Hamza
- Department of Chemistry, University of California Irvine, Irvine, CA92697
| | - Jonathan R. Lai
- Department of Biochemistry, Albert Einstein College of Medicine, Bronx, NY10461
| | - Vicki H. Wysocki
- Resource for Native Mass Spectrometry Guided Structural Biology, The Ohio State University, Columbus, OH43210
| | - James S. Nowick
- Department of Chemistry, University of California Irvine, Irvine, CA92697
- Department of Pharmaceutical Sciences, University of California Irvine, Irvine, CA92697
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3
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Wang Z, Jin M, Hong W, Liu W, Reczek D, Lagomarsino VN, Hu Y, Weeden T, Frosch MP, Young-Pearse TL, Pradier L, Selkoe D, Walsh DM. Learnings about Aβ from human brain recommend the use of a live-neuron bioassay for the discovery of next generation Alzheimer's disease immunotherapeutics. Acta Neuropathol Commun 2023; 11:39. [PMID: 36899414 PMCID: PMC10007750 DOI: 10.1186/s40478-023-01511-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2022] [Accepted: 01/10/2023] [Indexed: 03/12/2023] Open
Abstract
Despite ongoing debate, the amyloid β-protein (Aβ) remains the prime therapeutic target for the treatment of Alzheimer's disease (AD). However, rational drug design has been hampered by a lack of knowledge about neuroactive Aβ. To help address this deficit, we developed live-cell imaging of iPSC-derived human neurons (iNs) to study the effects of the most disease relevant form of Aβ-oligomeric assemblies (oAβ) extracted from AD brain. Of ten brains studied, extracts from nine caused neuritotoxicity, and in eight cases this was abrogated by Aβ immunodepletion. Here we show that activity in this bioassay agrees relatively well with disruption of hippocampal long-term potentiation, a correlate of learning and memory, and that measurement of neurotoxic oAβ can be obscured by more abundant non-toxic forms of Aβ. These findings indicate that the development of novel Aβ targeting therapeutics may benefit from unbiased activity-based discovery. To test this principle, we directly compared 5 clinical antibodies (aducanumab, bapineuzumab, BAN2401, gantenerumab, and SAR228810) together with an in-house aggregate-preferring antibody (1C22) and established relative EC50s in protecting human neurons from human Aβ. The results yielded objective numerical data on the potency of each antibody in neutralizing human oAβ neuritotoxicity. Their relative efficacies in this morphological assay were paralleled by their functional ability to rescue oAβ-induced inhibition of hippocampal synaptic plasticity. This novel paradigm provides an unbiased, all-human system for selecting candidate antibodies for advancement to human immunotherapy.
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Affiliation(s)
- Zemin Wang
- Laboratory for Neurodegenerative Research, Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital, Hale Building for Transformative Medicine, 60 Fenwood Road, Boston, MA, 02115, USA
| | - Ming Jin
- Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, 02115, USA
| | - Wei Hong
- Laboratory for Neurodegenerative Research, Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital, Hale Building for Transformative Medicine, 60 Fenwood Road, Boston, MA, 02115, USA
- The Brain Cognition and Brain Disease Institute, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences; Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, Shenzhen, Guangdong, China
| | - Wen Liu
- Laboratory for Neurodegenerative Research, Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital, Hale Building for Transformative Medicine, 60 Fenwood Road, Boston, MA, 02115, USA
| | - David Reczek
- Sanofi-Genzyme Corporation, Framingham, MA, 01701, USA
| | - Valentina N Lagomarsino
- Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, 02115, USA
| | - Yuan Hu
- Laboratory for Neurodegenerative Research, Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital, Hale Building for Transformative Medicine, 60 Fenwood Road, Boston, MA, 02115, USA
| | - Tim Weeden
- Sanofi-Genzyme Corporation, Framingham, MA, 01701, USA
| | - Matthew P Frosch
- Massachusetts General Institute for Neurodegenerative Disease, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA, 02129, USA
| | - Tracy L Young-Pearse
- Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, 02115, USA
| | | | - Dennis Selkoe
- Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, 02115, USA.
| | - Dominic M Walsh
- Laboratory for Neurodegenerative Research, Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital, Hale Building for Transformative Medicine, 60 Fenwood Road, Boston, MA, 02115, USA.
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4
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Hong W, Liu W, Desousa AO, Young-Pearse T, Walsh DM. Methods for the isolation and analysis of Aβ from postmortem brain. Front Neurosci 2023; 17:1108715. [PMID: 36777642 PMCID: PMC9909698 DOI: 10.3389/fnins.2023.1108715] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2022] [Accepted: 01/09/2023] [Indexed: 01/27/2023] Open
Abstract
Amyloid β-protein (Aβ) plays an initiating role in Alzheimer's disease (AD), but only a small number of groups have studied Aβ extracted from human brain. Most prior studies have utilized synthetic Aβ peptides, but the relevance of these test tube experiments to the conditions that prevail in AD is uncertain. Here, we describe three distinct methods for studying Aβ from cortical tissue. Each method allows the analysis of different ranges of species thus enabling the examination of different questions. The first method allows the study of readily diffusible Aβ with a relatively high specific activity. The second enables the analysis of readily solubilized forms of Aβ the majority of which are inactive. The third details the isolation of true Aβ dimers which have disease-related activity. We also describe a bioassay to study the effects of Aβ on the neuritic integrity of iPSC-derived human neurons. The combined use of this bioassay and the described extraction procedures provides a platform to investigate the activity of different forms and mixtures of Aβ species, and offers a tractable system to identify strategies to mitigate Aβ mediated neurotoxicity.
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Affiliation(s)
- Wei Hong
- Laboratory for Neurodegenerative Research, Ann Romney Center for Neurologic Diseases, Brigham and Women’s Hospital and Harvard Medical School, Boston, MA, United States,The Brain Cognition and Brain Disease Institute, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, Guangdong, China
| | - Wen Liu
- Laboratory for Neurodegenerative Research, Ann Romney Center for Neurologic Diseases, Brigham and Women’s Hospital and Harvard Medical School, Boston, MA, United States
| | - Alexandra O. Desousa
- Laboratory for Neurodegenerative Research, Ann Romney Center for Neurologic Diseases, Brigham and Women’s Hospital and Harvard Medical School, Boston, MA, United States
| | - Tracy Young-Pearse
- Ann Romney Center for Neurologic Diseases, Brigham and Women’s Hospital and Harvard Medical School, Boston, MA, United States
| | - Dominic M. Walsh
- Laboratory for Neurodegenerative Research, Ann Romney Center for Neurologic Diseases, Brigham and Women’s Hospital and Harvard Medical School, Boston, MA, United States,*Correspondence: Dominic M. Walsh,
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5
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Transferrin Biosynthesized in the Brain Is a Novel Biomarker for Alzheimer's Disease. Metabolites 2021; 11:metabo11090616. [PMID: 34564432 PMCID: PMC8470343 DOI: 10.3390/metabo11090616] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2021] [Revised: 09/01/2021] [Accepted: 09/03/2021] [Indexed: 01/23/2023] Open
Abstract
Glycosylation is a cell type-specific post-translational modification that can be used for biomarker identification in various diseases. Aim of this study is to explore glycan-biomarkers on transferrin (Tf) for Alzheimer’s disease (AD) in cerebrospinal fluid (CSF). Glycan structures of CSF Tf were analyzed by ultra-performance liquid chromatography followed by mass spectrometry. We found that a unique mannosylated-glycan is carried by a Tf isoform in CSF (Man-Tf). The cerebral cortex contained Man-Tf as a major isofom, suggesting that CSF Man-Tf is, at least partly, derived from the cortex. Man-Tf levels were analyzed in CSF of patients with neurological diseases. Concentrations of Man-Tf were significantly increased in AD and mild cognitive impairment (MCI) comparing with other neurological diseases, and the levels correlated well with those of phosphorylated-tau (p-tau), a representative AD marker. Consistent with the observation, p-tau and Tf were co-expressed in hippocampal neurons of AD, leading to the notion that a combined p-tau and Man-Tf measure could be a biomarker for AD. Indeed, levels of p-tau x Man-Tf showed high diagnostic accuracy for MCI and AD; 84% sensitivities and 90% specificities for MCI and 94% sensitivities and 89% specificities for AD. Thus Man-Tf could be a new biomarker for AD.
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6
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Sato K, Watamura N, Fujioka R, Mihira N, Sekiguchi M, Nagata K, Ohshima T, Saito T, Saido TC, Sasaguri H. A third-generation mouse model of Alzheimer's disease shows early and increased cored plaque pathology composed of wild-type human amyloid β peptide. J Biol Chem 2021; 297:101004. [PMID: 34329683 PMCID: PMC8397900 DOI: 10.1016/j.jbc.2021.101004] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Revised: 07/15/2021] [Accepted: 07/22/2021] [Indexed: 01/22/2023] Open
Abstract
We previously developed single App knock-in mouse models of Alzheimer's disease (AD) harboring the Swedish and Beyreuther/Iberian mutations with or without the Arctic mutation (AppNL-G-F and AppNL-F mice, respectively). These models showed Aβ pathology, neuroinflammation, and cognitive impairment in an age-dependent manner. The former model exhibits extensive pathology as early as 6 months, but is unsuitable for investigating Aβ metabolism and clearance because the Arctic mutation renders Aβ resistant to proteolytic degradation and prone to aggregation. In particular, it is inapplicable to preclinical immunotherapy studies due to its discrete affinity for anti-Aβ antibodies. The latter model may take as long as 18 months for the pathology to become prominent, which leaves an unfulfilled need for an Alzheimer's disease animal model that is both swift to show pathology and useful for antibody therapy. We thus utilized mutant Psen1 knock-in mice into which a pathogenic mutation (P117L) had been introduced to generate a new model that exhibits early deposition of wild-type human Aβ by crossbreeding the AppNL-F line with the Psen1P117L/WT line. We show that the effects of the pathogenic mutations in the App and Psen1 genes are additive or synergistic. This new third-generation mouse model showed more cored plaque pathology and neuroinflammation than AppNL-G-F mice and will help accelerate the development of disease-modifying therapies to treat preclinical AD.
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Affiliation(s)
- Kaori Sato
- Laboratory for Proteolytic Neuroscience, RIKEN Center for Brain Science, Wako, Saitama, Japan; Laboratory for Molecular Brain Science, Department of Life Science and Medical Bioscience, Waseda University, Shinjuku, Tokyo, Japan
| | - Naoto Watamura
- Laboratory for Proteolytic Neuroscience, RIKEN Center for Brain Science, Wako, Saitama, Japan
| | - Ryo Fujioka
- Laboratory for Proteolytic Neuroscience, RIKEN Center for Brain Science, Wako, Saitama, Japan
| | - Naomi Mihira
- Laboratory for Proteolytic Neuroscience, RIKEN Center for Brain Science, Wako, Saitama, Japan
| | - Misaki Sekiguchi
- Laboratory for Proteolytic Neuroscience, RIKEN Center for Brain Science, Wako, Saitama, Japan
| | - Kenichi Nagata
- Department of Functional Anatomy and Neuroscience, Nagoya University Graduate School of Medicine, Nagoya, Aichi, Japan
| | - Toshio Ohshima
- Laboratory for Molecular Brain Science, Department of Life Science and Medical Bioscience, Waseda University, Shinjuku, Tokyo, Japan
| | - Takashi Saito
- Department of Neurocognitive Science, Institute of Brain Science, Nagoya City University Graduate School of Medical Sciences, Nagoya, Aichi, Japan
| | - Takaomi C Saido
- Laboratory for Proteolytic Neuroscience, RIKEN Center for Brain Science, Wako, Saitama, Japan.
| | - Hiroki Sasaguri
- Laboratory for Proteolytic Neuroscience, RIKEN Center for Brain Science, Wako, Saitama, Japan.
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7
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Michno W, Blennow K, Zetterberg H, Brinkmalm G. Refining the amyloid β peptide and oligomer fingerprint ambiguities in Alzheimer's disease: Mass spectrometric molecular characterization in brain, cerebrospinal fluid, blood, and plasma. J Neurochem 2021; 159:234-257. [PMID: 34245565 DOI: 10.1111/jnc.15466] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Revised: 06/11/2021] [Accepted: 07/06/2021] [Indexed: 01/05/2023]
Abstract
Since its discovery, amyloid-β (Aβ) has been the principal target of investigation of in Alzheimer's disease (AD). Over the years however, no clear correlation was found between the Aβ plaque burden and location, and AD-associated neurodegeneration and cognitive decline. Instead, diagnostic potential of specific Aβ peptides and/or their ratio, was established. For instance, a selective reduction in the concentration of the aggregation-prone 42 amino acid-long Aβ peptide (Aβ42) in cerebrospinal fluid (CSF) was put forward as reflective of Aβ peptide aggregation in the brain. With time, Aβ oligomers-the proposed toxic Aβ intermediates-have emerged as potential drivers of synaptic dysfunction and neurodegeneration in the disease process. Oligomers are commonly agreed upon to come in different shapes and sizes, and are very poorly characterized when it comes to their composition and their "toxic" properties. The concept of structural polymorphism-a diversity in conformational organization of amyloid aggregates-that depends on the Aβ peptide backbone, makes the characterization of Aβ aggregates and their role in AD progression challenging. In this review, we revisit the history of Aβ discovery and initial characterization and highlight the crucial role mass spectrometry (MS) has played in this process. We critically review the common knowledge gaps in the molecular identity of the Aβ peptide, and how MS is aiding the characterization of higher order Aβ assemblies. Finally, we go on to present recent advances in MS approaches for characterization of Aβ as single peptides and oligomers, and convey our optimism, as to how MS holds a promise for paving the way for progress toward a more comprehensive understanding of Aβ in AD research.
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Affiliation(s)
- Wojciech Michno
- Institute of Neuroscience and Physiology, Department of Psychiatry and Neurochemistry, the Sahlgrenska Academy at the University of Gothenburg, Mölndal, Sweden.,Department of Neuroscience, Physiology and Pharmacology, University College London, London, UK.,Department of Pediatrics, Stanford University School of Medicine, Stanford University, Stanford, CA, USA
| | - Kaj Blennow
- Institute of Neuroscience and Physiology, Department of Psychiatry and Neurochemistry, the Sahlgrenska Academy at the University of Gothenburg, Mölndal, Sweden.,Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal, Sweden
| | - Henrik Zetterberg
- Institute of Neuroscience and Physiology, Department of Psychiatry and Neurochemistry, the Sahlgrenska Academy at the University of Gothenburg, Mölndal, Sweden.,Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal, Sweden.,Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, London, UK.,UK Dementia Research Institute at UCL, London, UK
| | - Gunnar Brinkmalm
- Institute of Neuroscience and Physiology, Department of Psychiatry and Neurochemistry, the Sahlgrenska Academy at the University of Gothenburg, Mölndal, Sweden.,Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal, Sweden
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8
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Wang K, Na L, Duan M. The Pathogenesis Mechanism, Structure Properties, Potential Drugs and Therapeutic Nanoparticles against the Small Oligomers of Amyloid-β. Curr Top Med Chem 2021; 21:151-167. [PMID: 32938351 DOI: 10.2174/1568026620666200916123000] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Revised: 08/02/2020] [Accepted: 08/13/2020] [Indexed: 12/27/2022]
Abstract
Alzheimer's Disease (AD) is a devastating neurodegenerative disease that affects millions of people in the world. The abnormal aggregation of amyloid β protein (Aβ) is regarded as the key event in AD onset. Meanwhile, the Aβ oligomers are believed to be the most toxic species of Aβ. Recent studies show that the Aβ dimers, which are the smallest form of Aβ oligomers, also have the neurotoxicity in the absence of other oligomers in physiological conditions. In this review, we focus on the pathogenesis, structure and potential therapeutic molecules against small Aβ oligomers, as well as the nanoparticles (NPs) in the treatment of AD. In this review, we firstly focus on the pathogenic mechanism of Aβ oligomers, especially the Aβ dimers. The toxicity of Aβ dimer or oligomers, which attributes to the interactions with various receptors and the disruption of membrane or intracellular environments, were introduced. Then the structure properties of Aβ dimers and oligomers are summarized. Although some structural information such as the secondary structure content is characterized by experimental technologies, detailed structures are still absent. Following that, the small molecules targeting Aβ dimers or oligomers are collected; nevertheless, all of these ligands have failed to come into the market due to the rising controversy of the Aβ-related "amyloid cascade hypothesis". At last, the recent progress about the nanoparticles as the potential drugs or the drug delivery for the Aβ oligomers are present.
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Affiliation(s)
- Ke Wang
- Key Laboratory of Magnetic Resonance in Biological Systems, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, National Center for Magnetic Resonance in Wuhan, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, China
| | - Liu Na
- School of Biological and Pharmaceutical Engineering, Wuhan Polytechnic University, Wuhan 430023, China
| | - Mojie Duan
- Key Laboratory of Magnetic Resonance in Biological Systems, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, National Center for Magnetic Resonance in Wuhan, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, China
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9
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Vosough F, Barth A. Characterization of Homogeneous and Heterogeneous Amyloid-β42 Oligomer Preparations with Biochemical Methods and Infrared Spectroscopy Reveals a Correlation between Infrared Spectrum and Oligomer Size. ACS Chem Neurosci 2021; 12:473-488. [PMID: 33455165 PMCID: PMC8023574 DOI: 10.1021/acschemneuro.0c00642] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
![]()
Soluble oligomers of the amyloid-β(1-42)
(Aβ42) peptide,
widely considered to be among the relevant neurotoxic species involved
in Alzheimer’s disease, were characterized with a combination
of biochemical and biophysical methods. Homogeneous and stable Aβ42
oligomers were prepared by treating monomeric solutions of the peptide
with detergents. The prepared oligomeric solutions were analyzed with
blue native and sodium dodecyl sulfate polyacrylamide gel electrophoresis,
as well as with infrared (IR) spectroscopy. The IR spectra indicated
a well-defined β-sheet structure of the prepared oligomers.
We also found a relationship between the size/molecular weight of
the Aβ42 oligomers and their IR spectra: The position of the
main amide I′ band of the peptide backbone correlated with
oligomer size, with larger oligomers being associated with lower wavenumbers.
This relationship explained the time-dependent band shift observed
in time-resolved IR studies of Aβ42 aggregation in the absence
of detergents, during which the oligomer size increased. In addition,
the bandwidth of the main IR band in the amide I′ region was
found to become narrower with time in our time-resolved aggregation
experiments, indicating a more homogeneous absorption of the β-sheets
of the oligomers after several hours of aggregation. This is predominantly
due to the consumption of smaller oligomers in the aggregation process.
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Affiliation(s)
- Faraz Vosough
- Department of Biochemistry and Biophysics, Stockholm University, Stockholm SE-106 91, Sweden
| | - Andreas Barth
- Department of Biochemistry and Biophysics, Stockholm University, Stockholm SE-106 91, Sweden
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10
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Brinkmalm G, Hong W, Wang Z, Liu W, O'Malley TT, Sun X, Frosch MP, Selkoe DJ, Portelius E, Zetterberg H, Blennow K, Walsh DM. Identification of neurotoxic cross-linked amyloid-β dimers in the Alzheimer's brain. Brain 2020; 142:1441-1457. [PMID: 31032851 DOI: 10.1093/brain/awz066] [Citation(s) in RCA: 60] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2018] [Revised: 01/19/2019] [Accepted: 01/27/2019] [Indexed: 11/13/2022] Open
Abstract
The primary structure of canonical amyloid-β-protein was elucidated more than 30 years ago, yet the forms of amyloid-β that play a role in Alzheimer's disease pathogenesis remain poorly defined. Studies of Alzheimer's disease brain extracts suggest that amyloid-β, which migrates on sodium dodecyl sulphate polyacrylamide gel electrophoresis with a molecular weight of ∼7 kDa (7kDa-Aβ), is particularly toxic; however, the nature of this species has been controversial. Using sophisticated mass spectrometry and sensitive assays of disease-relevant toxicity we show that brain-derived bioactive 7kDa-Aβ contains a heterogeneous mixture of covalently cross-linked dimers in the absence of any other detectable proteins. The identification of amyloid-β dimers may open a new phase of Alzheimer's research and allow a better understanding of Alzheimer's disease, and how to monitor and treat this devastating disorder. Future studies investigating the bioactivity of individual dimers cross-linked at known sites will be critical to this effort.
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Affiliation(s)
- Gunnar Brinkmalm
- Institute of Neuroscience and Physiology, Department of Psychiatry and Neurochemistry, the Sahlgrenska Academy at the University of Gothenburg, Mölndal, SE-431 80 Mölndal, Sweden.,Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal, SE-431 80 Mölndal, Sweden
| | - Wei Hong
- Laboratory for Neurodegenerative Research, Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA
| | - Zemin Wang
- Laboratory for Neurodegenerative Research, Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA
| | - Wen Liu
- Laboratory for Neurodegenerative Research, Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA
| | - Tiernan T O'Malley
- Laboratory for Neurodegenerative Research, Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA
| | - Xin Sun
- Laboratory for Neurodegenerative Research, Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA
| | - Matthew P Frosch
- Massachusetts General Institute for Neurodegenerative Disease, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA, USA
| | - Dennis J Selkoe
- Laboratory for Neurodegenerative Research, Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA
| | - Erik Portelius
- Institute of Neuroscience and Physiology, Department of Psychiatry and Neurochemistry, the Sahlgrenska Academy at the University of Gothenburg, Mölndal, SE-431 80 Mölndal, Sweden.,Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal, SE-431 80 Mölndal, Sweden
| | - Henrik Zetterberg
- Institute of Neuroscience and Physiology, Department of Psychiatry and Neurochemistry, the Sahlgrenska Academy at the University of Gothenburg, Mölndal, SE-431 80 Mölndal, Sweden.,Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal, SE-431 80 Mölndal, Sweden.,Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, London, UK.,UK Dementia Research Institute at UCL, London, UK
| | - Kaj Blennow
- Institute of Neuroscience and Physiology, Department of Psychiatry and Neurochemistry, the Sahlgrenska Academy at the University of Gothenburg, Mölndal, SE-431 80 Mölndal, Sweden.,Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal, SE-431 80 Mölndal, Sweden
| | - Dominic M Walsh
- Laboratory for Neurodegenerative Research, Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA
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11
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Saito T, Mihira N, Matsuba Y, Sasaguri H, Hashimoto S, Narasimhan S, Zhang B, Murayama S, Higuchi M, Lee VMY, Trojanowski JQ, Saido TC. Humanization of the entire murine Mapt gene provides a murine model of pathological human tau propagation. J Biol Chem 2019; 294:12754-12765. [PMID: 31273083 DOI: 10.1074/jbc.ra119.009487] [Citation(s) in RCA: 90] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2019] [Revised: 06/27/2019] [Indexed: 11/06/2022] Open
Abstract
In cortical regions of brains from individuals with preclinical or clinical Alzheimer's disease (AD), extracellular β-amyloid (Aβ) deposition precedes the aggregation of pathological intracellular tau (the product of the gene microtubule-associated protein tau (MAPT)). To our knowledge, current mouse models of tauopathy reconstitute tau pathology by overexpressing mutant human tau protein. Here, through a homologous recombination approach that replaced the entire murine Mapt gene with the human ortholog, we developed knock-in mice with humanized Mapt to create an in vivo platform for studying human tauopathy. Of note, the humanized Mapt expressed all six tau isoforms present in humans. We next cross-bred the MAPT knock-in mice with single amyloid precursor protein (App) knock-in mice to investigate the Aβ-tau axis in AD etiology. The double-knock-in mice exhibited higher tau phosphorylation than did single MAPT knock-in mice but initially lacked apparent tauopathy and neurodegeneration, as observed in the single App knock-in mice. We further observed that tau humanization significantly accelerates cell-to-cell propagation of AD brain-derived pathological tau both in the absence and presence of Aβ-amyloidosis. In the presence of Aβ-amyloidosis, tau accumulation was intensified and closely associated with dystrophic neurites, consistently showing that Aβ-amyloidosis affects tau pathology. Our results also indicated that the pathological human tau interacts better with human tau than with murine tau, suggesting species-specific differences between these orthologous pathogenic proteins. We propose that the MAPT knock-in mice will make it feasible to investigate the behaviors and characteristics of human tau in an animal model.
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Affiliation(s)
- Takashi Saito
- Laboratory for Proteolytic Neuroscience, RIKEN Center for Brain Science, 2-1 Hirosawa, Wako-city, Saitama 351-0198, Japan .,Department of Neuroscience and Pathobiology, Research Institute of Environmental Medicine, Nagoya University, Nagoya, Aichi 464-8601, Japan
| | - Naomi Mihira
- Laboratory for Proteolytic Neuroscience, RIKEN Center for Brain Science, 2-1 Hirosawa, Wako-city, Saitama 351-0198, Japan
| | - Yukio Matsuba
- Laboratory for Proteolytic Neuroscience, RIKEN Center for Brain Science, 2-1 Hirosawa, Wako-city, Saitama 351-0198, Japan
| | - Hiroki Sasaguri
- Laboratory for Proteolytic Neuroscience, RIKEN Center for Brain Science, 2-1 Hirosawa, Wako-city, Saitama 351-0198, Japan
| | - Shoko Hashimoto
- Laboratory for Proteolytic Neuroscience, RIKEN Center for Brain Science, 2-1 Hirosawa, Wako-city, Saitama 351-0198, Japan
| | - Sneha Narasimhan
- Department of Pathology and Laboratory Medicine, Institute on Aging and Center for Neurodegenerative Disease Research, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania 19104
| | - Bin Zhang
- Department of Pathology and Laboratory Medicine, Institute on Aging and Center for Neurodegenerative Disease Research, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania 19104
| | - Shigeo Murayama
- Department of Neuropathology, Tokyo Metropolitan Geriatric Hospital, 35-2 Sakaecho, Itabashi, Tokyo 173-0015, Japan
| | - Makoto Higuchi
- Department of Functional Brain Imaging Research, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba 263-8555, Japan
| | - Virginia M Y Lee
- Department of Pathology and Laboratory Medicine, Institute on Aging and Center for Neurodegenerative Disease Research, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania 19104
| | - John Q Trojanowski
- Department of Pathology and Laboratory Medicine, Institute on Aging and Center for Neurodegenerative Disease Research, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania 19104
| | - Takaomi C Saido
- Laboratory for Proteolytic Neuroscience, RIKEN Center for Brain Science, 2-1 Hirosawa, Wako-city, Saitama 351-0198, Japan
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12
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Hong W, Wang Z, Liu W, O'Malley TT, Jin M, Willem M, Haass C, Frosch MP, Walsh DM. Diffusible, highly bioactive oligomers represent a critical minority of soluble Aβ in Alzheimer's disease brain. Acta Neuropathol 2018; 136:19-40. [PMID: 29687257 PMCID: PMC6647843 DOI: 10.1007/s00401-018-1846-7] [Citation(s) in RCA: 76] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2018] [Accepted: 04/02/2018] [Indexed: 01/02/2023]
Abstract
Significant data suggest that soluble Aβ oligomers play an important role in Alzheimer's disease (AD), but there is great confusion over what exactly constitutes an Aβ oligomer and which oligomers are toxic. Most studies have utilized synthetic Aβ peptides, but the relevance of these test tube experiments to the conditions that prevail in AD is uncertain. A few groups have studied Aβ extracted from human brain, but they employed vigorous tissue homogenization which is likely to release insoluble Aβ that was sequestered in plaques during life. Several studies have found such extracts to possess disease-relevant activity and considerable efforts are being made to purify and better understand the forms of Aβ therein. Here, we compared the abundance of Aβ in AD extracts prepared by traditional homogenization versus using a far gentler extraction, and assessed their bioactivity via real-time imaging of iPSC-derived human neurons plus the sensitive functional assay of long-term potentiation. Surprisingly, the amount of Aβ retrieved by gentle extraction constituted only a small portion of that released by traditional homogenization, but this readily diffusible fraction retained all of the Aβ-dependent neurotoxic activity. Thus, the bulk of Aβ extractable from AD brain was innocuous, and only the small portion that was aqueously diffusible caused toxicity. This unexpected finding predicts that generic anti-oligomer therapies, including Aβ antibodies now in trials, may be bound up by the large pool of inactive oligomers, whereas agents that specifically target the small pool of diffusible, bioactive Aβ would be more useful. Furthermore, our results indicate that efforts to purify and target toxic Aβ must employ assays of disease-relevant activity. The approaches described here should enable these efforts, and may assist the study of other disease-associated aggregation-prone proteins.
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Affiliation(s)
- Wei Hong
- Laboratory for Neurodegenerative Research, Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital and Harvard Medical School, Building for Transformative Medicine, 60 Fenwood Road, Boston, MA, 02115, USA
| | - Zemin Wang
- Laboratory for Neurodegenerative Research, Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital and Harvard Medical School, Building for Transformative Medicine, 60 Fenwood Road, Boston, MA, 02115, USA
| | - Wen Liu
- Laboratory for Neurodegenerative Research, Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital and Harvard Medical School, Building for Transformative Medicine, 60 Fenwood Road, Boston, MA, 02115, USA
| | - Tiernan T O'Malley
- Laboratory for Neurodegenerative Research, Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital and Harvard Medical School, Building for Transformative Medicine, 60 Fenwood Road, Boston, MA, 02115, USA
| | - Ming Jin
- Laboratory for Neurodegenerative Research, Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital and Harvard Medical School, Building for Transformative Medicine, 60 Fenwood Road, Boston, MA, 02115, USA
| | - Michael Willem
- Biomedical Center (BMC), Biochemistry, Ludwig-Maximilians-University Munich, 81377, Munich, Germany
| | - Christian Haass
- Biomedical Center (BMC), Biochemistry, Ludwig-Maximilians-University Munich, 81377, Munich, Germany
- Munich Cluster for Systems Neurology (SyNergy), 81377, Munich, Germany
- German Center for Neurodegenerative Diseases (DZNE) Munich, 81377, Munich, Germany
| | - Matthew P Frosch
- Massachusetts General Institute for Neurodegenerative Disease, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA, 02129, USA
| | - Dominic M Walsh
- Laboratory for Neurodegenerative Research, Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital and Harvard Medical School, Building for Transformative Medicine, 60 Fenwood Road, Boston, MA, 02115, USA.
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13
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Hughes B, Herron CE. Cannabidiol Reverses Deficits in Hippocampal LTP in a Model of Alzheimer's Disease. Neurochem Res 2018; 44:703-713. [PMID: 29574668 DOI: 10.1007/s11064-018-2513-z] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2017] [Revised: 03/16/2018] [Accepted: 03/20/2018] [Indexed: 01/12/2023]
Abstract
Here we demonstrate for the first time that cannabidiol (CBD) acts to protect synaptic plasticity in an in vitro model of Alzheimer's disease (AD). The non-psycho active component of Cannabis sativa, CBD has previously been shown to protect against the neurotoxic effects of beta amyloid peptide (Aβ) in cell culture and cognitive behavioural models of neurodegeneration. Hippocampal long-term potentiation (LTP) is an activity dependent increase in synaptic efficacy often used to study cellular mechanisms related to memory. Here we show that acute application of soluble oligomeric beta amyloid peptide (Aβ1-42) associated with AD, attenuates LTP in the CA1 region of hippocampal slices from C57Bl/6 mice. Application of CBD alone did not alter LTP, however pre-treatment of slices with CBD rescued the Aβ1-42 mediated deficit in LTP. We found that the neuroprotective effects of CBD were not reversed by WAY100635, ZM241385 or AM251, demonstrating a lack of involvement of 5HT1A, adenosine (A2A) or Cannabinoid type 1 (CB1) receptors respectively. However in the presence of the PPARγ antagonist GW9662 the neuroprotective effect of CBD was prevented. Our data suggests that this major component of Cannabis sativa, which lacks psychoactivity may have therapeutic potential for the treatment of AD.
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Affiliation(s)
- Blathnaid Hughes
- School of Biomolecular and Biomedical Sciences, Conway Institute, University College Dublin, Dublin 4, Ireland
| | - Caroline E Herron
- School of Biomolecular and Biomedical Sciences, Conway Institute, University College Dublin, Dublin 4, Ireland.
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14
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Alzheimer's disease as oligomeropathy. Neurochem Int 2017; 119:57-70. [PMID: 28821400 DOI: 10.1016/j.neuint.2017.08.010] [Citation(s) in RCA: 79] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2017] [Revised: 07/30/2017] [Accepted: 08/13/2017] [Indexed: 12/21/2022]
Abstract
Alzheimer's disease (AD) is the most common age-related neurodegenerative disorder and is characterized by pathological aggregates of amyloid β-protein (Aβ) and tau protein. On the basis of genetic evidence, biochemical data, and animal models, Aβ has been suggested to be responsible for the pathogenesis of AD (the amyloid hypothesis). Aβ molecules tend to aggregate to form oligomers, protofibrils, and mature fibrils. Although mature fibrils in the final stage have been thought to be the cause of AD pathogenesis, recent studies using synthetic Aβ peptides, a cell culture model, Aβ precursor protein transgenic mice models, and human samples, such as cerebrospinal fluids and postmortem brains of AD patients, suggest that pre-fibrillar forms (oligomers of Aβ) are more deleterious than are extracellular fibril forms. Based on this recent evidence showing that oligomers have a central role in the pathogenesis of AD, the term "oligomeropathy" could be used to define AD and other protein-misfolding diseases. In this review, I discuss recent developments in the "oligomer hypothesis" including our research findings regarding the pathogenesis of AD.
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15
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Rudinskiy N, Fuerer C, Demurtas D, Zamorano S, De Piano C, Herrmann AG, Spires-Jones TL, Oeckl P, Otto M, Frosch MP, Moniatte M, Hyman BT, Schmid AW. Amyloid‐beta oligomerization is associated with the generation of a typical peptide fragment fingerprint. Alzheimers Dement 2016; 12:996-1013. [DOI: 10.1016/j.jalz.2016.03.011] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2015] [Revised: 02/29/2016] [Accepted: 03/19/2016] [Indexed: 10/21/2022]
Affiliation(s)
- Nikita Rudinskiy
- Department of Neurology, Alzheimer's Disease Research Laboratory, MassGeneral Institute for Neurodegenerative Disease, Massachusetts General Hospital Harvard Medical School Charlestown MA USA
| | - Christophe Fuerer
- School of Life Sciences, Proteomics Core Facility Ecole Polytechnique Fédérale de Lausanne (EPFL) Lausanne Switzerland
| | - Davide Demurtas
- School of Basic Sciences, Interdisciplinary Centre for Electron Microscopy (CIME) Ecole Polytechnique Fédérale de Lausanne (EPFL) Lausanne Switzerland
| | - Sebastian Zamorano
- School of Life Sciences, Proteomics Core Facility Ecole Polytechnique Fédérale de Lausanne (EPFL) Lausanne Switzerland
| | - Cyntia De Piano
- School of Life Sciences, Proteomics Core Facility Ecole Polytechnique Fédérale de Lausanne (EPFL) Lausanne Switzerland
| | - Abigail G. Herrmann
- Center for Cognitive and Neural Systems The University of Edinburgh Edinburgh Scotland
- Centre for Dementia Prevention The University of Edinburgh Edinburgh Scotland
- Euan MacDonald Centre for Motorneurone Disease The University of Edinburgh Edinburgh Scotland
| | - Tara L. Spires-Jones
- Center for Cognitive and Neural Systems The University of Edinburgh Edinburgh Scotland
- Centre for Dementia Prevention The University of Edinburgh Edinburgh Scotland
- Euan MacDonald Centre for Motorneurone Disease The University of Edinburgh Edinburgh Scotland
| | - Patrick Oeckl
- Department of Neurology Ulm University Hospital Ulm Germany
| | - Markus Otto
- Department of Neurology Ulm University Hospital Ulm Germany
| | - Matthew P. Frosch
- Massachusetts General Hospital and Harvard Medical School Massachusetts General Institute for Neurodegenerative Disease Charlestown MA USA
| | - Marc Moniatte
- School of Life Sciences, Proteomics Core Facility Ecole Polytechnique Fédérale de Lausanne (EPFL) Lausanne Switzerland
| | - Bradley T. Hyman
- Department of Neurology, Alzheimer's Disease Research Laboratory, MassGeneral Institute for Neurodegenerative Disease, Massachusetts General Hospital Harvard Medical School Charlestown MA USA
| | - Adrien W. Schmid
- School of Life Sciences, Proteomics Core Facility Ecole Polytechnique Fédérale de Lausanne (EPFL) Lausanne Switzerland
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16
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Jana MK, Cappai R, Pham CLL, Ciccotosto GD. Membrane-bound tetramer and trimer Aβ oligomeric species correlate with toxicity towards cultured neurons. J Neurochem 2016; 136:594-608. [DOI: 10.1111/jnc.13443] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2015] [Revised: 11/11/2015] [Accepted: 11/23/2015] [Indexed: 12/12/2022]
Affiliation(s)
- Metta K. Jana
- Department of Pathology; Bio21 Molecular Science and Biotechnology Institute; The University of Melbourne; Parkville Vic. Australia
| | - Roberto Cappai
- Department of Pathology; Bio21 Molecular Science and Biotechnology Institute; The University of Melbourne; Parkville Vic. Australia
| | - Chi L. L. Pham
- Department of Pathology; Bio21 Molecular Science and Biotechnology Institute; The University of Melbourne; Parkville Vic. Australia
| | - Giuseppe D. Ciccotosto
- Department of Pathology; Bio21 Molecular Science and Biotechnology Institute; The University of Melbourne; Parkville Vic. Australia
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17
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Singh SK, Srivastav S, Yadav AK, Srikrishna S, Perry G. Overview of Alzheimer's Disease and Some Therapeutic Approaches Targeting Aβ by Using Several Synthetic and Herbal Compounds. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2015; 2016:7361613. [PMID: 27034741 PMCID: PMC4807045 DOI: 10.1155/2016/7361613] [Citation(s) in RCA: 91] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/12/2015] [Accepted: 11/05/2015] [Indexed: 01/10/2023]
Abstract
Alzheimer's disease (AD) is a complex age-related neurodegenerative disease. In this review, we carefully detail amyloid-β metabolism and its role in AD. We also consider the various genetic animal models used to evaluate therapeutics. Finally, we consider the role of synthetic and plant-based compounds in therapeutics.
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Affiliation(s)
- Sandeep Kumar Singh
- Department of Biochemistry, Faculty of Science, Banaras Hindu University, Varanasi 221 005, India
| | - Saurabh Srivastav
- Department of Biochemistry, Faculty of Science, Banaras Hindu University, Varanasi 221 005, India
| | - Amarish Kumar Yadav
- Department of Biochemistry, Faculty of Science, Banaras Hindu University, Varanasi 221 005, India
| | - Saripella Srikrishna
- Department of Biochemistry, Faculty of Science, Banaras Hindu University, Varanasi 221 005, India
| | - George Perry
- Department of Biology, The University of Texas at San Antonio, San Antonio, TX 78249, USA
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18
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Puzzo D, Gulisano W, Arancio O, Palmeri A. The keystone of Alzheimer pathogenesis might be sought in Aβ physiology. Neuroscience 2015; 307:26-36. [PMID: 26314631 PMCID: PMC4591241 DOI: 10.1016/j.neuroscience.2015.08.039] [Citation(s) in RCA: 85] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2015] [Revised: 08/15/2015] [Accepted: 08/18/2015] [Indexed: 01/17/2023]
Abstract
For several years Amyloid-beta peptide (Aβ) has been considered the main pathogenetic factor of Alzheimer's disease (AD). According to the so called Amyloid Cascade Hypothesis the increase of Aβ triggers a series of events leading to synaptic dysfunction and memory loss as well as to the structural brain damage in the later stage of the disease. However, several evidences suggest that this hypothesis is not sufficient to explain AD pathogenesis, especially considering that most of the clinical trials aimed to decrease Aβ levels have been unsuccessful. Moreover, Aβ is physiologically produced in the healthy brain during neuronal activity and it is needed for synaptic plasticity and memory. Here we propose a model interpreting AD pathogenesis as an alteration of the negative feedback loop between Aβ and its physiological receptors, focusing on alpha7 nicotinic acetylcholine receptors (α7-nAchRs). According to this vision, when Aβ cannot exert its physiological function a negative feedback mechanism would induce a compensatory increase of its production leading to an abnormal accumulation that reduces α7-nAchR function, leading to synaptic dysfunction and memory loss. In this perspective, the indiscriminate Aβ removal might worsen neuronal homeostasis, causing a further impoverishment of learning and memory. Even if further studies are needed to better understand and validate these mechanisms, we believe that to deepen the role of Aβ in physiological conditions might represent the keystone to elucidate important aspects of AD pathogenesis.
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Affiliation(s)
- D Puzzo
- Department of Biomedical and Biotechnological Sciences, Section of Physiology, Viale A. Doria 6 (ed. 2), University of Catania, Catania 95125, Italy.
| | - W Gulisano
- Department of Biomedical and Biotechnological Sciences, Section of Physiology, Viale A. Doria 6 (ed. 2), University of Catania, Catania 95125, Italy
| | - O Arancio
- Department of Pathology and Cell Biology, Taub Institute for Research on Alzheimer's Disease and the Aging Brain, 630 West 168th Street, Columbia University, New York, NY 10032, USA
| | - A Palmeri
- Department of Biomedical and Biotechnological Sciences, Section of Physiology, Viale A. Doria 6 (ed. 2), University of Catania, Catania 95125, Italy
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19
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Role of amyloid-β CSF levels in cognitive deficit in MS. Clin Chim Acta 2015; 449:23-30. [DOI: 10.1016/j.cca.2015.01.035] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2015] [Accepted: 01/21/2015] [Indexed: 11/18/2022]
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20
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The aqueous phase of Alzheimer's disease brain contains assemblies built from ∼4 and ∼7 kDa Aβ species. Alzheimers Dement 2015; 11:1286-305. [PMID: 25846299 DOI: 10.1016/j.jalz.2015.01.005] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2014] [Revised: 12/17/2014] [Accepted: 01/06/2015] [Indexed: 12/27/2022]
Abstract
INTRODUCTION Much knowledge about amyloid β (Aβ) aggregation and toxicity has been acquired using synthetic peptides and mouse models, whereas less is known about soluble Aβ in human brain. METHODS We analyzed aqueous extracts from multiple AD brains using an array of techniques. RESULTS Brains can contain at least four different Aβ assembly forms including: (i) monomers, (ii) a ∼7 kDa Aβ species, and larger species (iii) from ∼30-150 kDa, and (iv) >160 kDa. High molecular weight species are by far the most prevalent and appear to be built from ∼7 kDa Aβ species. The ∼7 kDa Aβ species resist denaturation by chaotropic agents and have a higher Aβ42/Aβ40 ratio than monomers, and are unreactive with antibodies to Asp1 of Ab or APP residues N-terminal of Asp1. DISCUSSION Further analysis of brain-derived ∼7 kDa Aβ species, the mechanism by which they assemble and the structures they form should reveal therapeutic and diagnostic opportunities.
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21
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Pasi S, Kant R, Gupta S, Surolia A. Novel multimeric IL-1 receptor antagonist for the treatment of rheumatoid arthritis. Biomaterials 2014; 42:121-33. [PMID: 25542800 DOI: 10.1016/j.biomaterials.2014.11.041] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2014] [Revised: 11/17/2014] [Accepted: 11/24/2014] [Indexed: 12/20/2022]
Abstract
Protein therapeutics targeting inflammatory mediators have shown great promise for the treatment of autoimmunities such as rheumatoid arthritis (RA). However, a significant challenge in this area has been their low in vivo stability and consequently their severely compromised therapeutic efficacy. One such therapeutic molecule IL-1 receptor antagonist (IL-1ra), used in the treatment of rheumatoid arthritis, has displayed only modest efficacy in human clinical trials owing to its short biological half-life. Herein, we report a novel approach to conglomerate individual protein entities into a drug depot by incorporation of an amyloidogenic motif Lys-Phe-Phe-Glu (KFFE) thereby dramatically improving their systemic persistence and in turn their therapeutic efficacy in a mice model of autoimmune arthritis.
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Affiliation(s)
- Shweta Pasi
- Molecular Science Laboratory, National Institute of Immunology, New Delhi, India
| | - Ravi Kant
- Molecular Science Laboratory, National Institute of Immunology, New Delhi, India
| | - Sarika Gupta
- Molecular Science Laboratory, National Institute of Immunology, New Delhi, India
| | - Avadhesha Surolia
- Molecular Science Laboratory, National Institute of Immunology, New Delhi, India; Molecular Biophysics Unit, Indian Institute of Science, Bangalore, India.
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22
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Saito T, Matsuba Y, Mihira N, Takano J, Nilsson P, Itohara S, Iwata N, Saido TC. Single App knock-in mouse models of Alzheimer's disease. Nat Neurosci 2014; 17:661-3. [PMID: 24728269 DOI: 10.1038/nn.3697] [Citation(s) in RCA: 669] [Impact Index Per Article: 66.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2014] [Accepted: 03/12/2014] [Indexed: 11/09/2022]
Abstract
Experimental studies of Alzheimer's disease have largely depended on transgenic mice overexpressing amyloid precursor protein (APP). These mice, however, suffer from artificial phenotypes because, in addition to amyloid β peptide (Aβ), they overproduce other APP fragments. We generated knock-in mice that harbor Swedish and Beyreuther/Iberian mutations with and without the Arctic mutation in the APP gene. The mice showed typical Aβ pathology, neuroinflammation and memory impairment in an age-dependent manner.
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Affiliation(s)
- Takashi Saito
- 1] Laboratory for Proteolytic Neuroscience, RIKEN Brain Science Institute, Wako-shi, Saitama, Japan. [2] Japan Science and Technology Agency, Saitama, Japan
| | - Yukio Matsuba
- Laboratory for Proteolytic Neuroscience, RIKEN Brain Science Institute, Wako-shi, Saitama, Japan
| | - Naomi Mihira
- Laboratory for Proteolytic Neuroscience, RIKEN Brain Science Institute, Wako-shi, Saitama, Japan
| | - Jiro Takano
- Laboratory for Proteolytic Neuroscience, RIKEN Brain Science Institute, Wako-shi, Saitama, Japan
| | - Per Nilsson
- Laboratory for Proteolytic Neuroscience, RIKEN Brain Science Institute, Wako-shi, Saitama, Japan
| | - Shigeyoshi Itohara
- Laboratory for Behavioral Genetics, RIKEN Brain Science Institute, Wako-shi, Saitama, Japan
| | - Nobuhisa Iwata
- 1] Laboratory for Proteolytic Neuroscience, RIKEN Brain Science Institute, Wako-shi, Saitama, Japan. [2] Department of Molecular Medicinal Sciences, Division of Biotechnology, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan
| | - Takaomi C Saido
- Laboratory for Proteolytic Neuroscience, RIKEN Brain Science Institute, Wako-shi, Saitama, Japan
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23
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Hamley IW. The Amyloid Beta Peptide: A Chemist’s Perspective. Role in Alzheimer’s and Fibrillization. Chem Rev 2012; 112:5147-92. [DOI: 10.1021/cr3000994] [Citation(s) in RCA: 670] [Impact Index Per Article: 55.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- I. W. Hamley
- Department
of Chemistry, University of Reading, Whiteknights, Reading RG6 6AD,
U.K
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24
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Synaptic dysfunction in Alzheimer's disease. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2012; 970:573-601. [PMID: 22351073 DOI: 10.1007/978-3-7091-0932-8_25] [Citation(s) in RCA: 82] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Generation of amyloid peptide (Aβ) is at the beginning of a cascade that leads to Alzheimer's disease (AD). Amyloid precursor protein (APP), as well as β- and γ-secretases, is the principal player involved in Aβ production, while α-secretase cleavage on APP prevents Aβ deposition. Recent studies suggested that soluble assembly states of Aβ peptides can cause cognitive problems by disrupting synaptic function in the absence of significant neurodegeneration. Therefore, current research investigates the relative importance of these various soluble Aβ assemblies in causing synaptic dysfunction and cognitive deficits. Several Aβ oligomers targets and cellular mechanisms responsible of Aβ-induced synaptic failure have been identified. The first and most important mechanism impugns a toxic gain of function for Aβ which results due to self-association and attainment of new structures capable of novel interactions that lead to impaired plasticity. Other scenarios predicate that Aβ has a normal physiological role. On the one hand, insufficient Aβ could lead to a loss of normal function, whereas excess Aβ may precipitate dysfunction. How this occurs and which the main target/s is/are for the synaptic action of Aβ remains to be fully understood and would certainly represent one of the main challenges to future AD research.
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25
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Alzheimer's Disease and the Amyloid β-Protein. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2012; 107:101-24. [DOI: 10.1016/b978-0-12-385883-2.00012-6] [Citation(s) in RCA: 101] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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26
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Powell LR, Dukes KD, Lammi RK. Probing the efficacy of peptide-based inhibitors against acid- and zinc-promoted oligomerization of amyloid-β peptide via single-oligomer spectroscopy. Biophys Chem 2012; 160:12-9. [PMID: 21945664 PMCID: PMC3210411 DOI: 10.1016/j.bpc.2011.08.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2011] [Revised: 08/26/2011] [Accepted: 08/29/2011] [Indexed: 01/18/2023]
Abstract
One avenue for prevention and treatment of Alzheimer's disease involves inhibiting the aggregation of amyloid-β peptide (Aβ). Given the deleterious effects reported for Aβ dimers and trimers, it is important to investigate inhibition of the earliest association steps. We have employed quantized photobleaching of dye-labeled Aβ peptides to characterize four peptide-based inhibitors of fibrillogenesis and/or cytotoxicity, assessing their ability to inhibit association in the smallest oligomers (n=2-5). Inhibitors were tested at acidic pH and in the presence of zinc, conditions that may promote oligomerization in vivo. Distributions of peptide species were constructed by examining dozens of surface-tethered monomers and oligomers, one at a time. Results show that all four inhibitors shift the distribution of Aβ species toward monomers; however, efficacies vary for each compound and sample environment. Collectively, these studies highlight promising design strategies for future oligomerization inhibitors, affording insight into oligomer structures and inhibition mechanisms in two physiologically significant environments.
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Affiliation(s)
- Lyndsey R Powell
- Department of Chemistry, Physics and Geology, Winthrop University, Rock Hill, SC 29733, USA
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27
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Koffie RM, Hyman BT, Spires-Jones TL. Alzheimer's disease: synapses gone cold. Mol Neurodegener 2011; 6:63. [PMID: 21871088 PMCID: PMC3178498 DOI: 10.1186/1750-1326-6-63] [Citation(s) in RCA: 203] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2011] [Accepted: 08/26/2011] [Indexed: 11/21/2022] Open
Abstract
Alzheimer's disease (AD) is a progressive neurodegenerative disease characterized by insidious cognitive decline and memory dysfunction. Synapse loss is the best pathological correlate of cognitive decline in AD and mounting evidence suggests that AD is primarily a disease of synaptic dysfunction. Soluble oligomeric forms of amyloid beta (Aβ), the peptide that aggregates to form senile plaques in the brain of AD patients, have been shown to be toxic to neuronal synapses both in vitro and in vivo. Aβ oligomers inhibit long-term potentiation (LTP) and facilitate long-term depression (LTD), electrophysiological correlates of memory formation. Furthermore, oligomeric Aβ has also been shown to induce synapse loss and cognitive impairment in animals. The molecular underpinnings of these observations are now being elucidated, and may provide clear therapeutic targets for effectively treating the disease. Here, we review recent findings concerning AD pathogenesis with a particular focus on how Aβ impacts synapses.
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Affiliation(s)
- Robert M Koffie
- Massachusetts General Hospital, Harvard Medical School, 114 16th Street, Charlestown, MA 02129, USA.
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28
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Computational insights into the development of novel therapeutic strategies for Alzheimer's disease. Future Med Chem 2011; 1:119-35. [PMID: 21426072 DOI: 10.4155/fmc.09.10] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND β-amyloidosis and oxidative stress have been implicated as root causes of Alzheimer's disease (AD). Current potential therapeutic strategies for the treatment of AD include inhibition of amyloid β (Aβ) production, stimulation of Aβ degradation and prevention of Aβ oligomerization. However, efforts in this direction are hindered by the lack of understanding of the biochemical processes occurring at the atomic level in AD. DISCUSSION A radically different approach to achieve this goal would be the application of comprehensive theoretical and computational techniques such as molecular dynamics, quantum mechanics, hybrid quantum mechanics/molecular mechanics, bioinformatics and rotational spectroscopy to investigate complex chemical and physical processes in β-amyloidosis and the oxidative stress mechanism. CONCLUSION Results obtained from these studies will provide an atomic level understanding of biochemical processes occurring in AD and advance efforts to develop effective therapeutic strategies for this disease.
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29
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Saito T, Suemoto T, Brouwers N, Sleegers K, Funamoto S, Mihira N, Matsuba Y, Yamada K, Nilsson P, Takano J, Nishimura M, Iwata N, Van Broeckhoven C, Ihara Y, Saido TC. Potent amyloidogenicity and pathogenicity of Aβ43. Nat Neurosci 2011; 14:1023-32. [PMID: 21725313 DOI: 10.1038/nn.2858] [Citation(s) in RCA: 208] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2011] [Accepted: 05/13/2011] [Indexed: 11/09/2022]
Abstract
The amyloid-β peptide Aβ42 is known to be a primary amyloidogenic and pathogenic agent in Alzheimer's disease. However, the role of Aβ43, which is found just as frequently in the brains of affected individuals, remains unresolved. We generated knock-in mice containing a pathogenic presenilin-1 R278I mutation that causes overproduction of Aβ43. Homozygosity was embryonic lethal, indicating that the mutation involves a loss of function. Crossing amyloid precursor protein transgenic mice with heterozygous mutant mice resulted in elevated Aβ43, impairment of short-term memory and acceleration of amyloid-β pathology, which accompanied pronounced accumulation of Aβ43 in plaque cores similar in biochemical composition to those observed in the brains of affected individuals. Consistently, Aβ43 showed a higher propensity to aggregate and was more neurotoxic than Aβ42. Other pathogenic presenilin mutations also caused overproduction of Aβ43 in a manner correlating with Aβ42 and with the age of disease onset. These findings indicate that Aβ43, an overlooked species, is potently amyloidogenic, neurotoxic and abundant in vivo.
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Affiliation(s)
- Takashi Saito
- Laboratory for Proteolytic Neuroscience, RIKEN Brain Science Institute, Wako-shi, Saitama, Japan
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30
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Abstract
Alzheimer's disease is associated with synapse loss, memory dysfunction, and pathological accumulation of amyloid-β (Aβ) in plaques. However, an exclusively pathological role for Aβ is being challenged by new evidence for an essential function of Aβ at the synapse. Aβ protein exists in different assembly states in the central nervous system and plays distinct roles ranging from synapse and memory formation to memory loss and neuronal cell death. Aβ is present in the brain of symptom-free people where it likely performs important physiological roles. New evidence indicates that synaptic activity directly evokes the release of Aβ at the synapse. At physiological levels, Aβ is a normal, soluble product of neuronal metabolism that regulates synaptic function beginning early in life. Monomeric Aβ40 and Aβ42 are the predominant forms required for synaptic plasticity and neuronal survival. With age, some assemblies of Aβ are associated with synaptic failure and Alzheimer's disease pathology, possibly targeting the N-methyl-D-aspartic acid receptor through the nicotinic acetylcholine receptor, mitochondrial Aβ alcohol dehydrogenase, and cyclophilin D. But emerging data suggests a distinction between age effects on the target response in contrast to the assembly state or the accumulation of the peptide. Both aging and Aβ independently decrease neuronal plasticity. Our laboratory has reported that Aβ, glutamate, and lactic acid are each increasingly toxic with neuron age. The basis of the age-related toxicity partly resides in age-related mitochondrial dysfunction and an oxidative shift in mitochondrial and cytoplasmic redox potential. In turn, signaling through phosphorylated extracellular signal-regulated protein kinases is affected along with an age-independent increase in phosphorylated cAMP response element-binding protein. This review examines the long-awaited functional impact of Aβ on synaptic plasticity.
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Affiliation(s)
- Mordhwaj S Parihar
- School of Studies in Biotechnology & Zoology, Vikram University, Ujjain, MP, India
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31
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Takamura A, Kawarabayashi T, Yokoseki T, Shibata M, Morishima-Kawashima M, Saito Y, Murayama S, Ihara Y, Abe K, Shoji M, Michikawa M, Matsubara E. Dissociation of β-amyloid from lipoprotein in cerebrospinal fluid from Alzheimer's disease accelerates β-amyloid-42 assembly. J Neurosci Res 2011; 89:815-21. [PMID: 21394760 DOI: 10.1002/jnr.22615] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2010] [Revised: 12/17/2010] [Accepted: 01/11/2011] [Indexed: 11/09/2022]
Abstract
Monoclonal 2C3 specific to β-amyloid (Aβ) oligomers (AβOs) enabled us to test our hypothesis that the alteration of lipoprotein-Aβ interaction in the central nervous system (CNS) initiates and/or accelerates the cascade favoring Aβ assembly. Immunoprecipitation of frontal cortex employing 2C3 unequivocally detected soluble 4-, 8-, and 12-mers in Alzheimer's disease (AD) brains. Immunoblot analysis of the entorhinal cortex employing 2C3 revealed that the accumulation of soluble 12-mers precedes the appearance of neuronal loss or cognitive impairment and is enhanced as the Braak neurofibrially tangle (NFT) stages progress. The dissociation of soluble Aβ from lipoprotein particles occurs in cerebrospinal fluid (CSF), and the presence of lipoprotein-free oligomeric 2C3 conformers (4- to 35-mers) was evident, which mimic CNS environments. Such CNS environments may strongly affect conformation of soluble Aβ peptides, resulting in the conversion of soluble Aβ(42) monomers into soluble Aβ(42) assembly. The findings suggest that functionally declined lipoproteins may accelerate the generation of metabolic conditions leading to higher levels of soluble Aβ(42) assembly in the CNS.
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Affiliation(s)
- Ayumi Takamura
- Department of Alzheimer's Disease Research, Research Institute, National Center for Geriatrics and Gerontology, Aichi, Japan
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32
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Abstract
The pathogenesis of Alzheimer's disease involves the progressive accumulation of amyloid β-protein (Aβ). Recent studies using synthetic Aβ peptides, a cell culture model, Aβ precursor protein transgenic mice models suggest that pre-fibrillar forms of Aβ are more deleterious than extracellular fibril forms. Recent findings obtained using synthetic Aβ peptides and human samples indicated that low-n oligomers (from dimers to octamers) may be proximate toxins for neuron and synapse. Here, we review the recent studies on the soluble oligomers, especially low-n oligomers in Alzheimer's disease.
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Affiliation(s)
- Kenjiro Ono
- Department of Neurology and Neurobiology of Aging, Kanazawa University Graduate School of Medical Science, Kanazawa, Japan.
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33
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Saraiva AM, Cardoso I, Saraiva MJ, Tauer K, Pereira MC, Coelho MAN, Möhwald H, Brezesinski G. Randomization of amyloid-β-peptide(1-42) conformation by sulfonated and sulfated nanoparticles reduces aggregation and cytotoxicity. Macromol Biosci 2011; 10:1152-63. [PMID: 20480510 DOI: 10.1002/mabi.200900448] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The amyloid-β peptide (Aβ) plays a central role in the mechanism of Alzheimer's disease, being the main constituent of the plaque deposits found in AD brains. Aβ amyloid formation and deposition are due to a conformational switching to a β-enriched secondary structure. Our strategy to inhibit Aβ aggregation involves the re-conversion of Aβ conformation by adsorption to nanoparticles. NPs were synthesized by sulfonation and sulfation of polystyrene, leading to microgels and latexes. Both polymeric nanostructures affect the conformation of Aβ inducing an unordered state. Oligomerization was delayed and cytotoxicity reduced. The proper balance between hydrophilic moieties and hydrophobic chains seems to be an essential feature of effective NPs.
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Affiliation(s)
- Ana M Saraiva
- Max Planck Institute of Colloids and Interfaces, Wissenschaftspark Golm, Potsdam, Germany.
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34
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Abstract
The development of amyloid-containing neuritic plaques is an invariable characteristic of Alzheimer's diseases (AD). The conversion from monomeric amyloid β protein (Aβ) to oligomeric Aβ and finally neuritic plaques is highly dynamic. The specific Aβ species that is correlated with disease severity remains to be discovered. Oligomeric Aβ has been detected in cultured cells, rodent and human brains, as well as human cerebrospinal fluid. Synthetic, cell, and brain derived Aβ oligomers have been found to inhibit hippocampal long-term potentiation (LTP) and this effect can be suppressed by the blockage of Aβ oligomer formation. A large body of evidence suggests that Aβ oligomers inhibit N-methyl-D-aspartate receptor dependent LTP; additional receptors have also been found to elicit downstream pathways upon binding to Aβ oligomers. Amyloid antibodies and small molecular compounds that reduce brain Aβ levels and block Aβ oligomer formation are capable of reversing synaptic dysfunction and these approaches hold a promising therapeutic potential to rescue memory disruption.
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Affiliation(s)
- Weiming Xia
- Center for Neurologic Diseases, Department of Neurology, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA.
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35
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Mc Donald JM, Savva GM, Brayne C, Welzel AT, Forster G, Shankar GM, Selkoe DJ, Ince PG, Walsh DM. The presence of sodium dodecyl sulphate-stable Abeta dimers is strongly associated with Alzheimer-type dementia. ACTA ACUST UNITED AC 2010; 133:1328-41. [PMID: 20403962 DOI: 10.1093/brain/awq065] [Citation(s) in RCA: 211] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The molecular pathways leading to Alzheimer-type dementia are not well understood, but the amyloid beta-protein is believed to be centrally involved. The quantity of amyloid beta-protein containing plaques does not correlate well with clinical status, suggesting that if amyloid beta-protein is pathogenic it involves soluble non-plaque material. Using 43 brains from the Newcastle cohort of the population-representative Medical Research Council Cognitive Function and Ageing Study, we examined the relationship between biochemically distinct forms of amyloid beta-protein and the presence of Alzheimer-type dementia. Cortical samples were serially extracted with Tris-buffered saline, Tris-buffered saline containing 1% TX-100 and with 88% formic acid and extracts analysed for amyloid beta-protein by immunoprecipitation/western blotting. The cohort was divisible into those with dementia at death with (n = 14) or without (n = 10) significant Alzheimer-type pathology, and those who were not demented (n = 19). Amyloid beta-protein monomer in extracts produced using Tris-buffered saline and Tris-buffered saline containing 1% TX-100 were strongly associated with Alzheimer type dementia (P < 0.001) and sodium dodecyl sulphate-stable amyloid beta-protein dimer was detected specifically and sensitively in Tris-buffered saline, Tris-buffered saline containing 1% TX-100 and formic acid extracts of Alzheimer brain. Amyloid beta-protein monomer in the formic acid fraction closely correlated with diffuse and neuritic plaque burden, but was not specific for dementia. These findings support the hypothesis that soluble amyloid beta-protein is a major correlate of dementia associated with Alzheimer-type pathology and is likely to be intimately involved in the pathogenesis of cognitive failure.
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Affiliation(s)
- Jessica M Mc Donald
- Laboratory for Neurodegenerative Research, School of Biomolecular and Biomedical Science, Conway Institute, University College Dublin, Dublin 4, Republic of Ireland
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36
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Hellstrand E, Boland B, Walsh DM, Linse S. Amyloid β-protein aggregation produces highly reproducible kinetic data and occurs by a two-phase process. ACS Chem Neurosci 2010; 1:13-8. [PMID: 22778803 DOI: 10.1021/cn900015v] [Citation(s) in RCA: 305] [Impact Index Per Article: 21.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2009] [Accepted: 10/01/2009] [Indexed: 12/26/2022] Open
Abstract
Protein aggregation can lead to major disturbances of cellular processes and is associated with several diseases. We report kinetic and equilibrium data by ThT fluorescence and enzyme-linked immunosorbent assay of sufficient quality and reproducibility to form a basis for mechanistic understanding of amyloid β-peptide (Aβ) fibril formation. Starting from monomeric peptide in a pure buffer system without cosolvents, we find that the kinetics of Aβ aggregation vary strongly with peptide concentration in a highly predictable manner. The free Aβ concentration in equilibrium with fibrils was found to vary with total peptide concentration in a manner expected for a two-phase system. The free versus total Aβ concentration was linear up to ca. 0.2 μM, after which free Aβ decreased with total Aβ toward an asymptotic value. Our results imply that Aβ fibril formation arises from a sequence of events in a highly predictable manner.
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Affiliation(s)
- Erik Hellstrand
- Chemistry Department and Molecular
Protein Science, Lund University, P.O. Box 124, SE221 00 Lund, Sweden
| | - Barry Boland
- Laboratory for Neurodegenerative Research, Conway Institute, Belfield, University College Dublin, Dublin 4, Republic of Ireland
| | - Dominic M. Walsh
- Laboratory for Neurodegenerative Research, Conway Institute, Belfield, University College Dublin, Dublin 4, Republic of Ireland
| | - Sara Linse
- Chemistry Department and Molecular
Protein Science, Lund University, P.O. Box 124, SE221 00 Lund, Sweden
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37
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Reed MN, Hofmeister JJ, Jungbauer L, Welzel AT, Yu C, Sherman MA, Lesné S, LaDu MJ, Walsh DM, Ashe KH, Cleary JP. Cognitive effects of cell-derived and synthetically derived Aβ oligomers. Neurobiol Aging 2010; 32:1784-94. [PMID: 20031278 DOI: 10.1016/j.neurobiolaging.2009.11.007] [Citation(s) in RCA: 94] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2009] [Revised: 10/27/2009] [Accepted: 11/10/2009] [Indexed: 10/19/2022]
Abstract
Soluble forms of amyloid-β peptide (Aβ) are a molecular focus in Alzheimer's disease research. Soluble Aβ dimers (≈8 kDa), trimers (≈12 kDa), tetramers (≈16 kDa) and Aβ*56 (≈56 kDa) have shown biological activity. These Aβ molecules have been derived from diverse sources, including chemical synthesis, transfected cells, and mouse and human brain, leading to uncertainty about toxicity and potency. Herein, synthetic Aβ peptide-derived oligomers, cell- and brain-derived low-n oligomers, and Aβ*56, were injected intracerebroventricularly (icv) into rats assayed under the Alternating Lever Cyclic Ratio (ALCR) cognitive assay. Cognitive deficits were detected at 1.3 μM of synthetic Aβ oligomers and at low nanomolar concentrations of cell-secreted Aβ oligomers. Trimers, from transgenic mouse brain (Tg2576), did not cause cognitive impairment at any dose tested, whereas Aβ*56 induced concentration-dependent cognitive impairment at 0.9 and 1.3μM. Thus, while multiple forms of Aβ have cognition impairing activity, there are significant differences in effective concentration and potency.
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Affiliation(s)
- Miranda N Reed
- N. Bud Grossman Center, University of Minnesota, Minneapolis, MN 55455, United States
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38
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Rózga M, Bal W. The Cu(II)/Aβ/Human Serum Albumin Model of Control Mechanism for Copper-Related Amyloid Neurotoxicity. Chem Res Toxicol 2009; 23:298-308. [DOI: 10.1021/tx900358j] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Małgorzata Rózga
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawińskiego 5a, 02-106 Warsaw, Poland, and Central Institute for Labour Protection, National Research Institute, Czerniakowska 16, 00-701 Warsaw, Poland
| | - Wojciech Bal
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawińskiego 5a, 02-106 Warsaw, Poland, and Central Institute for Labour Protection, National Research Institute, Czerniakowska 16, 00-701 Warsaw, Poland
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39
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Shankar GM, Walsh DM. Alzheimer's disease: synaptic dysfunction and Abeta. Mol Neurodegener 2009; 4:48. [PMID: 19930651 PMCID: PMC2788538 DOI: 10.1186/1750-1326-4-48] [Citation(s) in RCA: 334] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2009] [Accepted: 11/23/2009] [Indexed: 01/21/2023] Open
Abstract
Synapse loss is an early and invariant feature of Alzheimer's disease (AD) and there is a strong correlation between the extent of synapse loss and the severity of dementia. Accordingly, it has been proposed that synapse loss underlies the memory impairment evident in the early phase of AD and that since plasticity is important for neuronal viability, persistent disruption of plasticity may account for the frank cell loss typical of later phases of the disease. Extensive multi-disciplinary research has implicated the amyloid β-protein (Aβ) in the aetiology of AD and here we review the evidence that non-fibrillar soluble forms of Aβ are mediators of synaptic compromise. We also discuss the possible mechanisms of Aβ synaptotoxicity and potential targets for therapeutic intervention.
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Affiliation(s)
- Ganesh M Shankar
- Center for Neurologic Diseases, Harvard Medical School and Brigham and Women's Hospital, Boston, MA, USA.
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40
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Abeta immunotherapy: intracerebral sequestration of Abeta by an anti-Abeta monoclonal antibody 266 with high affinity to soluble Abeta. J Neurosci 2009; 29:11393-8. [PMID: 19741145 DOI: 10.1523/jneurosci.2021-09.2009] [Citation(s) in RCA: 92] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Amyloid beta (Abeta) immunotherapy is emerging as a promising disease-modifying therapy for Alzheimer's disease, although the precise mechanisms whereby anti-Abeta antibodies act against amyloid deposition and cognitive deficits remain elusive. To test the "peripheral sink" theory, which postulates that the effects of anti-Abeta antibodies in the systemic circulation are to promote the Abeta efflux from brain to blood, we studied the clearance of (125)I-Abeta(1-40) microinjected into mouse brains after intraperitoneal administration of an anti-Abeta monoclonal antibody 266. (125)I-Abeta(1-40) was rapidly eliminated from brains with a half-life of approximately 30 min in control mice, whereas 266 significantly retarded the elimination of Abeta, presumably due to formation of Abeta-antibody complex in brains. Administration of 266 to APP transgenic mice increased the levels of monomer Abeta species in an antibody-bound form, without affecting that of total Abeta. We propose a novel mechanism of Abeta immunotherapy by the class of anti-Abeta antibodies that preferentially bind soluble Abeta, i.e., intracerebral, rather than peripheral, sequestration of soluble, monomer form of Abeta, thereby preventing the accumulation of multimeric toxic Abeta species in brains.
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41
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Dukes KD, Rodenberg CF, Lammi RK. Monitoring the earliest amyloid-β oligomers via quantized photobleaching of dye-labeled peptides. Anal Biochem 2008; 382:29-34. [DOI: 10.1016/j.ab.2008.07.011] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2008] [Revised: 07/08/2008] [Accepted: 07/14/2008] [Indexed: 10/21/2022]
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42
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Zameer A, Kasturirangan S, Emadi S, Nimmagadda SV, Sierks MR. Anti-oligomeric Abeta single-chain variable domain antibody blocks Abeta-induced toxicity against human neuroblastoma cells. J Mol Biol 2008; 384:917-28. [PMID: 18929576 DOI: 10.1016/j.jmb.2008.09.068] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2008] [Revised: 09/19/2008] [Accepted: 09/23/2008] [Indexed: 12/29/2022]
Abstract
The Amyloid-beta (Abeta) peptide is a major component of the amyloid plaques associated with Alzheimer's disease (AD). Recent studies suggest that the most toxic forms of Abeta are small, soluble oligomeric aggregates. Here, we report the isolation and characterization of a single-chain variable domain (scFv) antibody isolated against oligomeric Abeta using a protocol developed in our laboratory that combines phage display technology and atomic force microscopy (AFM). Starting with a randomized, single framework phage display library, after three rounds of selection against oligomeric Abeta, we identified an scFv that bound oligomeric Abeta specifically, but not monomeric or fibrillar forms. The anti-oligomeric scFv inhibits Abeta aggregation and toxicity, and reduces the toxicity of preformed oligomeric Abeta towards human neuroblastoma cells. When used to probe samples of human brain tissue, the scFv reacted with AD tissue but not a healthy control or Parkinson's disease brain samples. The anti-oligomeric Abeta scFv therefore has potential therapeutic and diagnostic applications in specifically targeting or identifying the toxic morphologies of Abeta in AD brains.
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Affiliation(s)
- Andleeb Zameer
- Department of Chemical Engineering, Arizona State University, Tempe, AZ 85287, USA
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43
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Irvine GB, El-Agnaf OM, Shankar GM, Walsh DM. Protein aggregation in the brain: the molecular basis for Alzheimer's and Parkinson's diseases. Mol Med 2008; 14:451-64. [PMID: 18368143 DOI: 10.2119/2007-00100.irvine] [Citation(s) in RCA: 364] [Impact Index Per Article: 22.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2007] [Accepted: 03/17/2008] [Indexed: 12/31/2022] Open
Abstract
Developing effective treatments for neurodegenerative diseases is one of the greatest medical challenges of the 21st century. Although many of these clinical entities have been recognized for more than a hundred years, it is only during the past twenty years that the molecular events that precipitate disease have begun to be understood. Protein aggregation is a common feature of many neurodegenerative diseases, and it is assumed that the aggregation process plays a central role in pathogenesis. In this process, one molecule (monomer) of a soluble protein interacts with other monomers of the same protein to form dimers, oligomers, and polymers. Conformation changes in three-dimensional structure of the protein, especially the formation of beta-strands, often accompany the process. Eventually, as the size of the aggregates increases, they may precipitate as insoluble amyloid fibrils, in which the structure is stabilized by the beta-strands interacting within a beta-sheet. In this review, we discuss this theme as it relates to the two most common neurodegenerative conditions-Alzheimer's and Parkinson's diseases.
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Affiliation(s)
- G Brent Irvine
- School of Medicine and Dentistry, The Queen's University of Belfast, Belfast, Northern Ireland.
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44
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Rahimi F, Shanmugam A, Bitan G. Structure-function relationships of pre-fibrillar protein assemblies in Alzheimer's disease and related disorders. Curr Alzheimer Res 2008; 5:319-41. [PMID: 18537546 DOI: 10.2174/156720508784533358] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Several neurodegenerative diseases, including Alzheimer's, Parkinson's, Huntington's and prion diseases, are characterized pathognomonically by the presence of intra- and/or extracellular lesions containing proteinaceous aggregates, and by extensive neuronal loss in selective brain regions. Related non-neuropathic systemic diseases, e.g., light-chain and senile systemic amyloidoses, and other organ-specific diseases, such as dialysis-related amyloidosis and type-2 diabetes mellitus, also are characterized by deposition of aberrantly folded, insoluble proteins. It is debated whether the hallmark pathologic lesions are causative. Substantial evidence suggests that these aggregates are the end state of aberrant protein folding whereas the actual culprits likely are transient, pre-fibrillar assemblies preceding the aggregates. In the context of neurodegenerative amyloidoses, the proteinaceous aggregates may eventuate as potentially neuroprotective sinks for the neurotoxic, oligomeric protein assemblies. The pre-fibrillar, oligomeric assemblies are believed to initiate the pathogenic mechanisms that lead to synaptic dysfunction, neuronal loss, and disease-specific regional brain atrophy. The amyloid beta-protein (Abeta), which is believed to cause Alzheimer's disease (AD), is considered an archetypal amyloidogenic protein. Intense studies have led to nominal, functional, and structural descriptions of oligomeric Abeta assemblies. However, the dynamic and metastable nature of Abeta oligomers renders their study difficult. Different results generated using different methodologies under different experimental settings further complicate this complex area of research and identification of the exact pathogenic assemblies in vivo seems daunting. Here we review structural, functional, and biological experiments used to produce and study pre-fibrillar Abeta assemblies, and highlight similar studies of proteins involved in related diseases. We discuss challenges that contemporary researchers are facing and future research prospects in this demanding yet highly important field.
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Affiliation(s)
- F Rahimi
- Department of Neurology, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, CA 90095-7334, USA
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45
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Selkoe DJ. Soluble oligomers of the amyloid beta-protein impair synaptic plasticity and behavior. Behav Brain Res 2008; 192:106-13. [PMID: 18359102 DOI: 10.1016/j.bbr.2008.02.016] [Citation(s) in RCA: 774] [Impact Index Per Article: 48.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2007] [Revised: 02/01/2008] [Accepted: 02/05/2008] [Indexed: 10/22/2022]
Abstract
During the last 25 years, neuropathological, biochemical, genetic, cell biological and even therapeutic studies in humans have all supported the hypothesis that the gradual cerebral accumulation of soluble and insoluble assemblies of the amyloid beta-protein (Abeta) in limbic and association cortices triggers a cascade of biochemical and cellular alterations that produce the clinical phenotype of Alzheimer's disease (AD). The reasons for elevated cortical Abeta42 levels in most patients with typical, late-onset AD are unknown, but based on recent work, these could turn out to include augmented neuronal release of Abeta during some kinds of synaptic activity. Elevated levels of soluble Abeta42 monomers enable formation of soluble oligomers that can diffuse into synaptic clefts. We have identified certain APP-expressing cultured cell lines that form low-n oligomers intracellularly and release a portion of them into the medium. We find that these naturally secreted soluble oligomers--at picomolar concentrations--can disrupt hippocampal LTP in slices and in vivo and can also impair the memory of a complex learned behavior in rats. Abeta trimers appear to be more potent in disrupting LTP than are dimers. The cell-derived oligomers also decrease dendritic spine density in organotypic hippocampal slice cultures, and this decrease can be prevented by administration of Abeta antibodies or small-molecule modulators of Abeta aggregation. This therapeutic progress has been accompanied by advances in imaging the Abeta deposits non-invasively in humans. A new diagnostic-therapeutic paradigm to successfully address AD and its harbinger, mild cognitive impairment-amnestic type, is emerging.
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Affiliation(s)
- Dennis J Selkoe
- Center for Neurologic Diseases, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA.
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Farris W, Schütz SG, Cirrito JR, Shankar GM, Sun X, George A, Leissring MA, Walsh DM, Qiu WQ, Holtzman DM, Selkoe DJ. Loss of neprilysin function promotes amyloid plaque formation and causes cerebral amyloid angiopathy. THE AMERICAN JOURNAL OF PATHOLOGY 2007; 171:241-51. [PMID: 17591969 PMCID: PMC1941603 DOI: 10.2353/ajpath.2007.070105] [Citation(s) in RCA: 115] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Cerebral deposition of the amyloid beta protein (Abeta), an invariant feature of Alzheimer's disease, reflects an imbalance between the rates of Abeta production and clearance. The causes of Abeta elevation in the common late-onset form of Alzheimer's disease (LOAD) are largely unknown. There is evidence that the Abeta-degrading protease neprilysin (NEP) is down-regulated in normal aging and LOAD. We asked whether a decrease in endogenous NEP levels can prolong the half-life of Abeta in vivo and promote development of the classic amyloid neuropathology of Alzheimer's disease. We examined the brains and plasma of young and old mice expressing relatively low levels of human amyloid precursor protein and having one or both NEP genes silenced. NEP loss of function 1) elevated whole-brain and plasma levels of human Abeta(40) and Abeta(42), 2) prolonged the half-life of soluble Abeta in brain interstitial fluid of awake animals, 3) raised the concentration of Abeta dimers, 4) markedly increased hippocampal amyloid plaque burden, and 5) led to the development of amyloid angiopathy. A approximately 50% reduction in NEP levels, similar to that reported in some LOAD brains, was sufficient to increase amyloid neuropathology. These findings demonstrate an important role for proteolysis in determining the levels of Abeta and Abeta-associated neuropathology in vivo and support the hypothesis that primary defects in Abeta clearance can cause or contribute to LOAD pathogenesis.
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Affiliation(s)
- Wesley Farris
- Center for Neurologic Diseases, Department of Neurology, Harvard Institutes of Medicine, Room 730, Boston, MA 02115, USA.
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Morishima-Kawashima M, Han X, Tanimura Y, Hamanaka H, Kobayashi M, Sakurai T, Yokoyama M, Wada K, Nukina N, Fujita SC, Ihara Y. Effects of human apolipoprotein E isoforms on the amyloid beta-protein concentration and lipid composition in brain low-density membrane domains. J Neurochem 2007; 101:949-58. [PMID: 17472586 PMCID: PMC2151839 DOI: 10.1111/j.1471-4159.2006.04400.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Apolipoprotein E4 (apoE4) encoded by epsilon 4 allele is a strong genetic risk factor for Alzheimer's disease (AD). ApoE4 carriers have accelerated amyloid beta-protein (A beta) deposition in their brains, which may account for their unusual susceptibility to AD. We hypothesized that the accelerated A beta deposition in the brain of apoE4 carriers is mediated through cholesterol-enriched low-density membrane (LDM) domains. Thus, the concentrations of A beta and various lipids in LDM domains were quantified in the brains of homozygous apoE3 and apoE4 knock-in (KI) mice, and in the brains of those mice bred with beta-amyloid precursor protein (APP) transgenic mice (Tg2576). The A beta 40 and A beta 42 concentrations and the A beta 42 proportions in LDM domains did not differ between apoE3 and apoE4 KI mice up to 18 months of age. The A beta 40 concentration in the LDM domains was slightly, but significantly higher in apoE3/APP mice than in apoE4/APP mice. The lipid composition of LDM domains was modulated in an apoE isoform-specific manner, but its significance for A beta deposition remains unknown. These data show that the apoE isoform-specific effects on the A beta concentration in LDM domains do not occur in KI mouse models.
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Affiliation(s)
| | - Xianlin Han
- Division of Bioorganic Chemistry and Molecular Pharmacology, Department of Internal Medicine, Washington University School of Medicine, St Louis, Missouri, USA
| | - Yu Tanimura
- Department of Neuropathology, Faculty of Medicine, University of Tokyo, Tokyo, Japan
| | - Hiroki Hamanaka
- Molecular Neuropathology Group, RIKEN Brain Science Institute, Saitama, Japan
- Mitsubishi Kagaku Institute of Life Sciences, Tokyo, Japan
| | | | - Takashi Sakurai
- Molecular Neuropathology Group, RIKEN Brain Science Institute, Saitama, Japan
| | | | - Koji Wada
- Molecular Neuropathology Group, RIKEN Brain Science Institute, Saitama, Japan
| | - Nobuyuki Nukina
- Molecular Neuropathology Group, RIKEN Brain Science Institute, Saitama, Japan
| | | | - Yasuo Ihara
- Department of Neuropathology, Faculty of Medicine, University of Tokyo, Tokyo, Japan
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Atamna H, Frey WH. Mechanisms of mitochondrial dysfunction and energy deficiency in Alzheimer's disease. Mitochondrion 2007; 7:297-310. [PMID: 17625988 DOI: 10.1016/j.mito.2007.06.001] [Citation(s) in RCA: 177] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2007] [Accepted: 06/06/2007] [Indexed: 12/31/2022]
Abstract
Several studies have demonstrated aberrations in the Electron Transport Complexes (ETC) and Krebs (TCA) cycle in Alzheimer's disease (AD) brain. Optimal activity of these key metabolic pathways depends on several redox active centers and metabolites including heme, coenzyme Q, iron-sulfur, vitamins, minerals, and micronutrients. Disturbed heme metabolism leads to increased aberrations in the ETC (loss of complex IV), dimerization of APP, free radical production, markers of oxidative damage, and ultimately cell death all of which represent key cytopathologies in AD. The mechanism of mitochondrial dysfunction in AD is controversial. The observations that Abeta is found both in the cells and in the mitochondria and that Abeta binds with heme may provide clues to this mechanism. Mitochondrial Abeta may interfere with key metabolites or metabolic pathways in a manner that overwhelms the mitochondrial mechanisms of repair. Identifying the molecular mechanism for how Abeta interferes with mitochondria and that explains the established key cytopathologies in AD may also suggest molecular targets for therapeutic interventions. Below we review recent studies describing the possible role of Abeta in altered energy production through heme metabolism. We further discuss how protecting mitochondria could confer resistance to oxidative and environmental insults. Therapies targeted at protecting mitochondria may improve the clinical outcome of AD patients.
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Affiliation(s)
- Hani Atamna
- Nutrition and Metabolism Center, Children's Hospital Oakland Research Institute, 5700 Martin Luther King Jr. Way, Oakland, CA 94609-1673, USA.
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Haass C, Selkoe DJ. Soluble protein oligomers in neurodegeneration: lessons from the Alzheimer's amyloid beta-peptide. Nat Rev Mol Cell Biol 2007; 8:101-12. [PMID: 17245412 DOI: 10.1038/nrm2101] [Citation(s) in RCA: 3566] [Impact Index Per Article: 209.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The distinct protein aggregates that are found in Alzheimer's, Parkinson's, Huntington's and prion diseases seem to cause these disorders. Small intermediates - soluble oligomers - in the aggregation process can confer synaptic dysfunction, whereas large, insoluble deposits might function as reservoirs of the bioactive oligomers. These emerging concepts are exemplified by Alzheimer's disease, in which amyloid beta-protein oligomers adversely affect synaptic structure and plasticity. Findings in other neurodegenerative diseases indicate that a broadly similar process of neuronal dysfunction is induced by diffusible oligomers of misfolded proteins.
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Affiliation(s)
- Christian Haass
- Adolf Butenandt Institute, Department of Biochemistry, Laboratory for Alzheimer's and Parkinson's Disease Research, Ludwig Maximilians University, 80336 Munich, Germany.
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Abstract
Converging lines of evidence suggest that progressive accumulation of the amyloid beta-protein (A beta) plays a central role in the genesis of Alzheimer's disease, but it was long assumed that A beta had to be assembled into extracellular amyloid fibrils to exert its cytotoxic effects. Over the past decade, data have emerged from the use of synthetic A beta peptides, cell culture models, beta-amyloid precursor protein transgenic mice and human brain to suggest that pre-fibrillar, diffusible assemblies of A beta are also deleterious. Although the precise molecular identity of these soluble toxins remains unsettled, accumulating evidence suggests that soluble forms of A beta are indeed the proximate effectors of synapse loss and neuronal injury. Here we review recent progress in understanding the role of soluble oligomers in Alzheimer's disease.
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Affiliation(s)
- Dominic M Walsh
- Laboratory for Neurodegenerative Research, The Conway Institute, University College Dublin, Belfield, Dublin, Republic of Ireland.
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