101
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Suprun EV, Khmeleva SA, Radko SP, Archakov AI, Shumyantseva VV. Electrochemical Analysis of Amyloid-β Domain 1-16 Isoforms and Their Complexes with Zn(II) Ions. Electrochim Acta 2016. [DOI: 10.1016/j.electacta.2015.11.111] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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102
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Immunotherapy Against N-Truncated Amyloid-β Oligomers. METHODS IN PHARMACOLOGY AND TOXICOLOGY 2016. [DOI: 10.1007/978-1-4939-3560-4_3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/05/2022]
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103
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Müller-Schiffmann A, Herring A, Abdel-Hafiz L, Chepkova AN, Schäble S, Wedel D, Horn AHC, Sticht H, de Souza Silva MA, Gottmann K, Sergeeva OA, Huston JP, Keyvani K, Korth C. Amyloid-β dimers in the absence of plaque pathology impair learning and synaptic plasticity. Brain 2015; 139:509-25. [DOI: 10.1093/brain/awv355] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2015] [Accepted: 10/17/2015] [Indexed: 11/12/2022] Open
Abstract
Abstract
Despite amyloid plaques, consisting of insoluble, aggregated amyloid-β peptides, being a defining feature of Alzheimer’s disease, their significance has been challenged due to controversial findings regarding the correlation of cognitive impairment in Alzheimer’s disease with plaque load. The amyloid cascade hypothesis defines soluble amyloid-β oligomers, consisting of multiple amyloid-β monomers, as precursors of insoluble amyloid-β plaques. Dissecting the biological effects of single amyloid-β oligomers, for example of amyloid-β dimers, an abundant amyloid-β oligomer associated with clinical progression of Alzheimer’s disease, has been difficult due to the inability to control the kinetics of amyloid-β multimerization. For investigating the biological effects of amyloid-β dimers, we stabilized amyloid-β dimers by an intermolecular disulphide bridge via a cysteine mutation in the amyloid-β peptide (Aβ-S8C) of the amyloid precursor protein. This construct was expressed as a recombinant protein in cells and in a novel transgenic mouse, termed tgDimer mouse. This mouse formed constant levels of highly synaptotoxic soluble amyloid-β dimers, but not monomers, amyloid-β plaques or insoluble amyloid-β during its lifespan. Accordingly, neither signs of neuroinflammation, tau hyperphosphorylation or cell death were observed. Nevertheless, these tgDimer mice did exhibit deficits in hippocampal long-term potentiation and age-related impairments in learning and memory, similar to what was observed in classical Alzheimer’s disease mouse models. Although the amyloid-β dimers were unable to initiate the formation of insoluble amyloid-β aggregates in tgDimer mice, after crossbreeding tgDimer mice with the CRND8 mouse, an amyloid-β plaque generating mouse model, Aβ-S8C dimers were sequestered into amyloid-β plaques, suggesting that amyloid-β plaques incorporate neurotoxic amyloid-β dimers that by themselves are unable to self-assemble. Our results suggest that within the fine interplay between different amyloid-β species, amyloid-β dimer neurotoxic signalling, in the absence of amyloid-β plaque pathology, may be involved in causing early deficits in synaptic plasticity, learning and memory that accompany Alzheimer’s disease.
10.1093/brain/awv355_video_abstract awv355_video_abstract
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Affiliation(s)
| | - Arne Herring
- 2 Institute of Neuropathology, University of Duisburg-Essen, Germany
| | - Laila Abdel-Hafiz
- 3 Centre for Behavioural Neuroscience, Heinrich Heine University, Düsseldorf, Germany
| | - Aisa N. Chepkova
- 4 Institute for Neuro- and Sensory Physiology, Heinrich Heine University, Düsseldorf, Germany
| | - Sandra Schäble
- 3 Centre for Behavioural Neuroscience, Heinrich Heine University, Düsseldorf, Germany
- *Present address: Comparative Psychology, Institute of Experimental Psychology, Heinrich Heine University, Düsseldorf, Germany
| | - Diana Wedel
- 1 Department Neuropathology, Heinrich Heine University, Düsseldorf, Germany
| | - Anselm H. C. Horn
- 5 Institute for Biochemistry, Friedrich Alexander University Erlangen-Nürnberg, Erlangen, Germany
| | - Heinrich Sticht
- 5 Institute for Biochemistry, Friedrich Alexander University Erlangen-Nürnberg, Erlangen, Germany
| | | | - Kurt Gottmann
- 4 Institute for Neuro- and Sensory Physiology, Heinrich Heine University, Düsseldorf, Germany
| | - Olga A. Sergeeva
- 4 Institute for Neuro- and Sensory Physiology, Heinrich Heine University, Düsseldorf, Germany
| | - Joseph P. Huston
- 3 Centre for Behavioural Neuroscience, Heinrich Heine University, Düsseldorf, Germany
| | - Kathy Keyvani
- 2 Institute of Neuropathology, University of Duisburg-Essen, Germany
| | - Carsten Korth
- 1 Department Neuropathology, Heinrich Heine University, Düsseldorf, Germany
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104
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Mc Donald JM, O'Malley TT, Liu W, Mably AJ, Brinkmalm G, Portelius E, Wittbold WM, Frosch MP, Walsh DM. 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 PMCID: PMC4592782 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] [MESH Headings] [Grants] [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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Affiliation(s)
- Jessica M Mc Donald
- Laboratory for Neurodegenerative Research, Center for Neurologic Diseases, Brigham and Women's Hospital and Harvard Medical School, Harvard Institutes of Medicine, Boston, MA, USA
| | - Tiernan T O'Malley
- Laboratory for Neurodegenerative Research, Center for Neurologic Diseases, Brigham and Women's Hospital and Harvard Medical School, Harvard Institutes of Medicine, Boston, MA, USA; School of Biomolecular and Biomedical Science, University College Dublin, Dublin, Republic of Ireland
| | - Wen Liu
- Laboratory for Neurodegenerative Research, Center for Neurologic Diseases, Brigham and Women's Hospital and Harvard Medical School, Harvard Institutes of Medicine, Boston, MA, USA
| | - Alexandra J Mably
- Laboratory for Neurodegenerative Research, Center for Neurologic Diseases, Brigham and Women's Hospital and Harvard Medical School, Harvard Institutes of Medicine, Boston, MA, USA
| | - Gunnar Brinkmalm
- Clinical Neurochemistry Laboratory, Department of Neuroscience and Physiology, University of Göteborg, Sahlgrenska University Hospital, Mölndal, Sweden
| | - Erik Portelius
- Clinical Neurochemistry Laboratory, Department of Neuroscience and Physiology, University of Göteborg, Sahlgrenska University Hospital, Mölndal, Sweden
| | | | - Matthew P Frosch
- Massachusetts General Hospital and Harvard Medical School, Massachusetts General Institute for Neurodegenerative Disease, Charlestown, MA, USA
| | - Dominic M Walsh
- Laboratory for Neurodegenerative Research, Center for Neurologic Diseases, Brigham and Women's Hospital and Harvard Medical School, Harvard Institutes of Medicine, Boston, MA, USA.
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105
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Korsak M, Kozyreva T. Beta Amyloid Hallmarks: From Intrinsically Disordered Proteins to Alzheimer’s Disease. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2015; 870:401-21. [DOI: 10.1007/978-3-319-20164-1_14] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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106
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Balakrishnan K, Rijal Upadhaya A, Steinmetz J, Reichwald J, Abramowski D, Fändrich M, Kumar S, Yamaguchi H, Walter J, Staufenbiel M, Thal DR. Impact of amyloid β aggregate maturation on antibody treatment in APP23 mice. Acta Neuropathol Commun 2015; 3:41. [PMID: 26141728 PMCID: PMC4491274 DOI: 10.1186/s40478-015-0217-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2015] [Accepted: 06/08/2015] [Indexed: 12/31/2022] Open
Abstract
Introduction The deposition of the amyloid β protein (Aβ) in the brain is a hallmark of Alzheimer's disease (AD). Removal of Aβ by Aβ-antibody treatment has been developed as a potential treatment strategy against AD. First clinical trials showed neither a stop nor a reduction of disease progression. Recently, we have shown that the formation of soluble and insoluble Aβ aggregates in the human brain follows a hierarchical sequence of three biochemical maturation stages (B-Aβ stages). To test the impact of the B-Aβ stage on Aβ immunotherapy, we treated transgenic mice expressing human amyloid precursor protein (APP) carrying the Swedish mutation (KM670/671NL; APP23) with the Aβ-antibody β1 or phosphate-buffered saline (PBS) beginning 1) at 3 months, before the onset of dendrite degeneration and plaque deposition, and 2) at 7 months, after the start of Aβ plaque deposition and dendrite degeneration. Results At 5 months of age, first Aβ aggregates in APP23 brain consisted of non-modified Aβ (representing B-Aβ stage 1) whereas mature Aβ-aggregates containing N-terminal truncated, pyroglutamate-modified AβN3pE and phosphorylated Aβ (representing B-Aβ stage 3) were found at 11 months of age in both β1- and PBS-treated animals. Protective effects on commissural neurons with highly ramified dendritic trees were observed only in 3-month-old β1-treated animals sacrificed at 5 months. When treatment started at 7 months of age, no differences in the numbers of healthy commissural neurons were observed between β1- and PBS-treated APP23 mice sacrificed with 11 months. Conclusions Aβ antibody treatment was capable of protecting neurons from dendritic degeneration as long as Aβ aggregation was absent or represented B-Aβ stage 1 but had no protective or curative effect in later stages with mature Aβ aggregates (B-Aβ stage 3). These data indicate that the maturation stage of Aβ aggregates has impact on potential treatment effects in APP23 mice. Electronic supplementary material The online version of this article (doi:10.1186/s40478-015-0217-z) contains supplementary material, which is available to authorized users.
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107
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Ratnayaka JA, Serpell LC, Lotery AJ. Dementia of the eye: the role of amyloid beta in retinal degeneration. Eye (Lond) 2015; 29:1013-26. [PMID: 26088679 PMCID: PMC4541342 DOI: 10.1038/eye.2015.100] [Citation(s) in RCA: 116] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2015] [Accepted: 04/23/2015] [Indexed: 11/09/2022] Open
Abstract
Age-related macular degeneration (AMD) is one of the most common causes of irreversible blindness affecting nearly 50 million individuals globally. The disease is characterised by progressive loss of central vision, which has significant implications for quality of life concerns in an increasingly ageing population. AMD pathology manifests in the macula, a specialised region of the retina, which is responsible for central vision and perception of fine details. The underlying pathology of this complex degenerative disease is incompletely understood but includes both genetic as well as epigenetic risk factors. The recent discovery that amyloid beta (Aβ), a highly toxic and aggregate-prone family of peptides, is elevated in the ageing retina and is associated with AMD has opened up new perspectives on the aetiology of this debilitating blinding disease. Multiple studies now link Aβ with key stages of AMD progression, which is both exciting and potentially insightful, as this identifies a well-established toxic agent that aggressively targets cells in degenerative brains. Here, we review the most recent findings supporting the hypothesis that Aβ may be a key factor in AMD pathology. We describe how multiple Aβ reservoirs, now reported in the ageing eye, may target the cellular physiology of the retina as well as associated layers, and propose a mechanistic pathway of Aβ-mediated degenerative change leading to AMD.
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Affiliation(s)
- J A Ratnayaka
- Clinical and Experimental Science, Faculty of Medicine, University of Southampton, Southampton, UK
| | - L C Serpell
- School of Life Sciences (Biochemistry, Dementia Research Group), University of Sussex, Brighton, UK
| | - A J Lotery
- Clinical and Experimental Science, Faculty of Medicine, University of Southampton, Southampton, UK
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108
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Khmeleva SA, Mezentsev YV, Kozin SA, Mitkevich VA, Medvedev AE, Ivanov AS, Bodoev NV, Makarov AA, Radko SP. Effect of mutations and modifications of amino acid residues on zinc-induced interaction of the metal-binding domain of β-amyloid with DNA. Mol Biol 2015. [DOI: 10.1134/s0026893315020053] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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109
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Few-layer bismuth selenides exfoliated by hemin inhibit amyloid-β1-42 fibril formation. Sci Rep 2015; 5:10171. [PMID: 26018135 PMCID: PMC4446900 DOI: 10.1038/srep10171] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2014] [Accepted: 04/01/2015] [Indexed: 11/09/2022] Open
Abstract
Inhibiting amyloid-β (Aβ) fibril formation is the primary therapeutic strategy for Alzheimer's disease. Several small molecules and nanomaterials have been used to inhibit Aβ fibril formation. However, insufficient inhibition efficiency or poor metabolization limits their further applications. Here, we used hemin to exfoliate few-layer Bi(2)Se(3) in aqueous solution. Then we separated few-layer Bi(2)Se(3) with different sizes and thicknesses by fractional centrifugation, and used them to attempt to inhibit Aβ(1-42) aggregation. The results show that smaller and thinner few-layer Bi(2)Se(3) had the highest inhibition efficiency. We further investigated the interaction between few-layer Bi(2)Se(3) and Aβ(1-42) monomers. The results indicate that the inhibition effect may be due to the high adsorption capacity of few-layer Bi(2)Se(3) for Aβ(1-42) monomers. Few-layer Bi(2)Se(3) also decreased Aβ-mediated peroxidase-like activity and cytotoxicity according to in vitro neurotoxicity studies under physiological conditions. Therefore, our work shows the potential for applications of few-layer Bi(2)Se(3) in the biomedical field.
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110
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Bayer TA. Proteinopathies, a core concept for understanding and ultimately treating degenerative disorders? Eur Neuropsychopharmacol 2015; 25:713-24. [PMID: 23642796 DOI: 10.1016/j.euroneuro.2013.03.007] [Citation(s) in RCA: 76] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/18/2012] [Revised: 03/12/2013] [Accepted: 03/24/2013] [Indexed: 10/26/2022]
Abstract
The current review covers proteinopathies an umbrella term for neurodegenerative disorders that are characterized by the accumulation of specific proteins within neurons or in the brain parenchyma. Most prevalent examples for typical proteinopathies are Alzheimer's disease and Parkinson's disease. In healthy brain, these proteins are unstructured as a monomer, serving most likely as the physiological form. In a disease condition, the unstructured proteins experience a conformational change leading to small oligomers that eventually will aggregate into higher order structures. Prion disease is an exception within the family of proteinopathies as the aggregated prion protein is highly infectious and can self-aggregate and propagate. Recent reports might implicate a prion-like spread of misfolded proteins in Alzheimer's and Parkinson's disease; however there are evident differences in comparison to prion diseases. As proteinopathies are caused by the aggregation of disease-typical proteins with an ordered structure, active and passive immunization protocols have been used to expose model systems to therapeutic antibodies that bind to the aggregates thereby inhibiting the prolongation into higher ordered fibrils or dissolving the existing fibrillar structure. While most of the immunization treatments have been only carried out in preclinical model systems overexpressing the disease-relevant aggregating protein, other approaches are already in clinical testing. Taking the core concept of proteinopathies with conformationally altered protein aggregates into account, immunization appears to be a very promising therapeutic option for neurodegenerative disorders.
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Affiliation(s)
- Thomas A Bayer
- The Georg-August-University Göttingen, University Medicine Göttingen, Division of Molecular Psychiatry, Von-Siebold-Strasse 5, 37075 Göttingen, Germany.
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111
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Murakami K. Conformation-specific antibodies to target amyloid β oligomers and their application to immunotherapy for Alzheimer's disease. Biosci Biotechnol Biochem 2015; 78:1293-305. [PMID: 25130729 DOI: 10.1080/09168451.2014.940275] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Amyloid β-protein (Aβ) oligomers, intermediates of Aβ aggregation, cause cognitive impairment and synaptotoxicity in the pathogenesis of Alzheimer's disease (AD). Immunotherapy using anti-Aβ antibody is one of the most promising approaches for AD treatment. However, most clinical trials using conventional sequence-specific antibodies have proceeded with difficulty. This is probably due to the unintended removal of the non-pathological monomer and fibrils of Aβ as well as the pathological oligomers by these antibodies that recognize Aβ sequence, which is not involved in synaptotoxicity. Several efforts have been made recently to develop conformation-specific antibodies that target the tertiary structure of Aβ oligomers. Here, we review the recent findings of Aβ oligomers and anti-Aβ antibodies including our own, and discuss their potential as therapeutic and diagnostic tools.
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Affiliation(s)
- Kazuma Murakami
- a Division of Food Science and Biotechnology , Graduate School of Agriculture, Kyoto University , Kyoto , Japan
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112
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Kulikova AA, Makarov AA, Kozin SA. Roles of zinc ions and structural polymorphism of β-amyloid in the development of Alzheimer’s disease. Mol Biol 2015. [DOI: 10.1134/s0026893315020065] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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113
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Thal DR. Clearance of amyloid β-protein and its role in the spreading of Alzheimer's disease pathology. Front Aging Neurosci 2015; 7:25. [PMID: 25805990 PMCID: PMC4353250 DOI: 10.3389/fnagi.2015.00025] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2015] [Accepted: 02/22/2015] [Indexed: 11/13/2022] Open
Affiliation(s)
- Dietmar R Thal
- Laboratory of Neuropathology - Institute of Pathology, Center for Biomedical Research, University of Ulm Ulm, Germany
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114
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Rouget R, Sharma G, LeBlanc AC. Cyclin-dependent kinase 5 phosphorylation of familial prion protein mutants exacerbates conversion into amyloid structure. J Biol Chem 2015; 290:5759-71. [PMID: 25572400 DOI: 10.1074/jbc.m114.630699] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Familial prion protein (PrP) mutants undergo conversion from soluble and protease-sensitive to insoluble and partially protease-resistant proteins. Cyclin-dependent kinase 5 (Cdk5) phosphorylation of wild type PrP (pPrP) at serine 43 induces a conversion of PrP into aggregates and fibrils. Here, we investigated whether familial PrP mutants are predisposed to Cdk5 phosphorylation and whether phosphorylation of familial PrP mutants increases conversion. PrP mutants representing three major familial PrP diseases and different PrP structural domains were studied. We developed a novel in vitro kinase reaction coupled with Thioflavin T binding to amyloid structure assay to monitor phosphorylation-dependent amyloid conversion. Although non-phosphorylated full-length wild type or PrP mutants did not convert into amyloid, Cdk5 phosphorylation rapidly converted these into Thioflavin T-positive structures following first order kinetics. Dephosphorylation partially reversed conversion. Phosphorylation-dependent conversion of PrP from α-helical structures into β-sheet structures was confirmed by circular dichroism. Relative to wild type pPrP, most PrP mutants showed increased rate constants of conversion. In contrast, non-phosphorylated truncated PrP Y145X (where X represents a stop codon) and Q160X mutants converted spontaneously into Thioflavin T-positive fibrils after a lag phase of over 20 h, indicating nucleation-dependent polymerization. Phosphorylation reduced the lag phase by over 50% and thus accelerated the formation of the nucleating event. Consistently, phosphorylated Y145X and phosphorylated Q160X exacerbated conversion in a homologous seeding reaction, whereas WT pPrP could not seed WT PrP. These results demonstrate an influence of both the N terminus and the C terminus of PrP on conversion. We conclude that post-translational modifications of the flexible N terminus of PrP can cause or exacerbate PrP mutant conversion.
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Affiliation(s)
- Raphaël Rouget
- From the Lady Davis Institute for Medical Research, Sir Mortimer B. Davis Jewish General Hospital, Department of Neurology and Neurosurgery, McGill University, Montréal, Québec H3T 1E2, Canada and
| | - Gyanesh Sharma
- From the Lady Davis Institute for Medical Research, Sir Mortimer B. Davis Jewish General Hospital, Department of Neurology and Neurosurgery, McGill University, Montréal, Québec H3T 1E2, Canada and Department of Neurology and Neurosurgery, McGill University, 3775 University Street, Montréal, Québec H3A 2B4, Canada
| | - Andréa C LeBlanc
- From the Lady Davis Institute for Medical Research, Sir Mortimer B. Davis Jewish General Hospital, Department of Neurology and Neurosurgery, McGill University, Montréal, Québec H3T 1E2, Canada and Department of Neurology and Neurosurgery, McGill University, 3775 University Street, Montréal, Québec H3A 2B4, Canada
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115
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Kardos J, Kiss B, Micsonai A, Rovó P, Menyhárd DK, Kovács J, Váradi G, Tóth GK, Perczel A. Phosphorylation as conformational switch from the native to amyloid state: Trp-cage as a protein aggregation model. J Phys Chem B 2015; 119:2946-55. [PMID: 25625571 DOI: 10.1021/jp5124234] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The 20 residue long Trp-cage miniprotein is an excellent model for both computational and experimental studies of protein folding and stability. Recently, great attention emerged to study disease-related protein misfolding, aggregation, and amyloid formation, with the aim of revealing their structural and thermodynamic background. Trp-cage is sensitive to both environmental and structure-modifying effects. It aggregates with ease upon structure destabilization, and thus it is suitable for modeling aggregation and amyloid formation. Here, we characterize the amyloid formation of several sequence modified and side-chain phosphorylated Trp-cage variants. We applied NMR, circular dichroism (CD) and Fourier transform infrared (FTIR) spectroscopies, molecular dynamics (MD) simulations, and transmission electron microscopy (TEM) in conjunction with thioflavin-T (ThT) fluorescence measurements to reveal the structural consequences of side-chain phosphorylation. We demonstrate that the native fold is destabilized upon serine phosphorylation, and the resultant highly dynamic structures form amyloid-like ordered aggregates with high intermolecular β-structure content. The only exception is the D9S(P) variant, which follows an alternative aggregation process by forming thin fibrils, presenting a CD spectrum of PPII helix, and showing low ThT binding capability. We propose a complex aggregation model for these Trp-cage miniproteins. This model assumes an additional aggregated state, a collagen triple helical form that can precede amyloid formation. The phosphorylation of a single serine residue serves as a conformational switch, triggering aggregation, otherwise mediated by kinases in cell. We show that Trp-cage miniprotein is indeed a realistic model of larger globular systems of composite folding and aggregation landscapes and helps us to understand the fundamentals of deleterious protein aggregation and amyloid formation.
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Affiliation(s)
- József Kardos
- Department of Biochemistry, ‡MTA-ELTE NAP B Neuroimmunology Research Group, and §Department of Anatomy, Cell and Developmental Biology, Institute of Biology Eötvös Loránd University , Pázmány P. sétány 1/C, Budapest, H-1117 Hungary
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Thal DR, Walter J, Saido TC, Fändrich M. Neuropathology and biochemistry of Aβ and its aggregates in Alzheimer's disease. Acta Neuropathol 2015; 129:167-82. [PMID: 25534025 DOI: 10.1007/s00401-014-1375-y] [Citation(s) in RCA: 194] [Impact Index Per Article: 21.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2014] [Revised: 12/09/2014] [Accepted: 12/13/2014] [Indexed: 12/31/2022]
Abstract
Alzheimer's disease (AD) is characterized by β-amyloid plaques and intraneuronal τ aggregation usually associated with cerebral amyloid angiopathy (CAA). Both β-amyloid plaques and CAA deposits contain fibrillar aggregates of the amyloid β-peptide (Aβ). Aβ plaques and CAA develop first in neocortical areas of preclinical AD patients and, then, expand in a characteristic sequence into further brain regions with end-stage pathology in symptomatic AD patients. Aβ aggregates are not restricted to amyloid plaques and CAA. Soluble and several types of insoluble non-plaque- and non-CAA-associated Aβ aggregates have been described. Amyloid fibrils are products of a complex self-assembly process that involves different types of transient intermediates. Amongst these intermediate species are protofibrils and oligomers. Different variants of Aβ peptides may result from alternative processing or from mutations that lead to rare forms of familial AD. These variants can exhibit different self-assembly and aggregation properties. In addition, several post-translational modifications of Aβ have been described that result, for example, in the production of N-terminal truncated Aβ with pyroglutamate modification at position 3 (AβN3pE) or of Aβ phosphorylated at serine 8 (pSer8Aβ). Both AβN3pE and pSer8Aβ show enhanced aggregation into oligomers and fibrils. However, the earliest detectable soluble and insoluble Aβ aggregates in the human brain exhibit non-modified Aβ, whereas AβN3pE and pSer8Aβ are detected in later stages. This finding indicates the existence of different biochemical stages of Aβ aggregate maturation with pSer8Aβ being related mainly to cases with symptomatic AD. The conversion from preclinical to symptomatic AD could thereby be related to combined effects of increased Aβ concentration, maturation of aggregates and spread of deposits into additional brain regions. Thus, the inhibition of Aβ aggregation and maturation before entering the symptomatic stage of the disease as indicated by the accumulation of pSer8Aβ may represent an attractive treatment strategy for preventing disease progression.
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117
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Kozin SA, Makarov AA. New biomarkers and drug targets for diagnosis and therapy of Alzheimer’s disease (molecular determinants of zinc-dependent oligomerization of β-amyloid). Zh Nevrol Psikhiatr Im S S Korsakova 2015; 115:5-9. [DOI: 10.17116/jnevro2015115115-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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118
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The multifaceted nature of amyloid precursor protein and its proteolytic fragments: friends and foes. Acta Neuropathol 2015; 129:1-19. [PMID: 25287911 DOI: 10.1007/s00401-014-1347-2] [Citation(s) in RCA: 154] [Impact Index Per Article: 17.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2014] [Revised: 09/26/2014] [Accepted: 09/26/2014] [Indexed: 12/29/2022]
Abstract
The amyloid precursor protein (APP) has occupied a central position in Alzheimer's disease (AD) pathophysiology, in large part due to the seminal role of amyloid-β peptide (Aβ), a proteolytic fragment derived from APP. Although the contribution of Aβ to AD pathogenesis is accepted by many in the research community, recent studies have unveiled a more complicated picture of APP's involvement in neurodegeneration in that other APP-derived fragments have been shown to exert pathological influences on neuronal function. However, not all APP-derived peptides are neurotoxic, and some even harbor neuroprotective effects. In this review, we will explore this complex picture by first discussing the pleiotropic effects of the major APP-derived peptides cleaved by multiple proteases, including soluble APP peptides (sAPPα, sAPPβ), various C- and N-terminal fragments, p3, and APP intracellular domain fragments. In addition, we will highlight two interesting sequences within APP that likely contribute to this duality in APP function. First, it has been found that caspase-mediated cleavage of APP in the cytosolic region may release a cytotoxic peptide, C31, which plays a role in synapse loss and neuronal death. Second, recent studies have implicated the -YENPTY- motif in the cytoplasmic region as a domain that modulates several APP activities through phosphorylation and dephosphorylation of the first tyrosine residue. Thus, this review summarizes the current understanding of various APP proteolytic products and the interplay among them to gain deeper insights into the possible mechanisms underlying neurodegeneration and AD pathophysiology.
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119
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Omata Y, Lim YM, Akao Y, Tsuda L. Age-induced reduction of autophagy-related gene expression is associated with onset of Alzheimer's disease. AMERICAN JOURNAL OF NEURODEGENERATIVE DISEASE 2014; 3:134-142. [PMID: 25628964 PMCID: PMC4299720] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 09/16/2014] [Accepted: 11/06/2014] [Indexed: 06/04/2023]
Abstract
Aging is a major risk factor for Alzheimer's disease (AD). Aggregation of amyloid beta (Aβ) in cerebral cortex and hippocampus is a hallmark of AD. Many factors have been identified as causative elements for onset and progression of AD; for instance, tau seems to mediate the neuronal toxicity of Aβ, and downregulation of macroautophagy (autophagy) is thought to be a causative element of AD pathology. Expression of autophagy-related genes is reduced with age, which leads to increases in oxidative stress and aberrant protein accumulation. In this study, we found that expression of the autophagy-related genes atg1, atg8a, and atg18 in Drosophila melanogaster was regulated with aging as well as their own activities. In addition, the level of atg18 was maintained by dfoxo (foxo) and dsir2 (sir2) activities in concert with aging. These results indicate that some autophagy-related gene expression is regulated by foxo/sir2-mediated aging processes. We further found that reduced autophagy activity correlated with late-onset neuronal dysfunction caused by neuronal induction of Aβ. These data support the idea that age-related dysfunction of autophagy is a causative element in onset and progression of AD.
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Affiliation(s)
- Yasuhiro Omata
- Department of Occupational and Environmental Health, Graduate School of Medicine, Nagoya UniversityNagoya, Aichi, Japan
| | - Young-Mi Lim
- Animal Models of Aging, CAMD, National Center for Geriatrics and GerontologyObu, Aichi, Japan
| | - Yukihiro Akao
- United Graduate School of Drug Discovery and Medical Information Sciences, Gifu UniversityGifu City, Gifu, Japan
| | - Leo Tsuda
- Animal Models of Aging, CAMD, National Center for Geriatrics and GerontologyObu, Aichi, Japan
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120
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Peng J, Weng J, Ren L, Sun L. Interactions between gold nanoparticles and amyloid
β
25–35
peptide. IET Nanobiotechnol 2014; 8:295-303. [DOI: 10.1049/iet-nbt.2013.0071] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Affiliation(s)
- Jian Peng
- Department of BiomaterialsCollege of MaterialsXiamen UniversityXiamen 361005People's Republic of China
| | - Jian Weng
- Department of BiomaterialsCollege of MaterialsXiamen UniversityXiamen 361005People's Republic of China
| | - Lei Ren
- Department of BiomaterialsCollege of MaterialsXiamen UniversityXiamen 361005People's Republic of China
| | - Li‐Ping Sun
- Department of BiomaterialsCollege of MaterialsXiamen UniversityXiamen 361005People's Republic of China
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121
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Kam TI, Gwon Y, Jung YK. Amyloid beta receptors responsible for neurotoxicity and cellular defects in Alzheimer's disease. Cell Mol Life Sci 2014; 71:4803-13. [PMID: 25151011 PMCID: PMC11113744 DOI: 10.1007/s00018-014-1706-0] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2014] [Revised: 07/24/2014] [Accepted: 08/13/2014] [Indexed: 01/11/2023]
Abstract
Alzheimer's disease (AD) is the most common neurodegenerative disease. Although a major cause of AD is the accumulation of amyloid-β (Aβ) peptide that induces neuronal loss and cognitive impairments, our understanding of its neurotoxic mechanisms is limited. Recent studies have identified putative Aβ-binding receptors that mediate Aβ neurotoxicity in cells and models of AD. Once Aβ interacts with a receptor, a toxic signal is transduced into neurons, resulting in cellular defects including endoplasmic reticulum stress and mitochondrial dysfunction. In addition, Aβ can also be internalized into neurons through unidentified Aβ receptors and induces malfunction of subcellular organelles, which explains some part of Aβ neurotoxicity. Understanding the neurotoxic signaling initiated by Aβ-receptor binding and cellular defects provide insight into new therapeutic windows for AD. In the present review, we summarize the findings on Aβ-binding receptors and the neurotoxicity of oligomeric Aβ.
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Affiliation(s)
- Tae-In Kam
- Global Research Laboratory, School of Biological Sciences, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 151-747 Korea
| | - Youngdae Gwon
- Global Research Laboratory, School of Biological Sciences, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 151-747 Korea
| | - Yong-Keun Jung
- Global Research Laboratory, School of Biological Sciences, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 151-747 Korea
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122
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Popov IA, Indeikina MI, Pekov SI, Starodubtseva NL, Kononikhin AS, Nikolaeva MI, Kukaev EN, Kostyukevich YI, Kozin SA, Makarov AA, Nikolaev EN. Estimation of phosphorylation level of amyloid-beta isolated from human blood plasma: Ultrahigh-resolution mass spectrometry. Mol Biol 2014. [DOI: 10.1134/s0026893314040098] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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123
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Yalak G, Ehrlich YH, Olsen BR. Ecto-protein kinases and phosphatases: an emerging field for translational medicine. J Transl Med 2014; 12:165. [PMID: 24923278 PMCID: PMC4071215 DOI: 10.1186/1479-5876-12-165] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2014] [Accepted: 05/29/2014] [Indexed: 12/30/2022] Open
Abstract
Progress in translational research has led to effective new treatments of a large number of diseases. Despite this progress, diseases including cancer and cardiovascular disorders still are at the top in death statistics and disorders such as osteoporosis and osteoarthritis represent an increasing disease burden in the aging population. Novel strategies in research are needed more than ever to overcome such diseases. The growing field of extracellular protein phosphorylation provides excellent opportunities to make major discoveries of disease mechanisms that can lead to novel therapies. Reversible phosphorylation/dephosphorylation of sites in the extracellular domains of matrix, cell-surface and trans-membrane proteins is emerging as a critical regulatory mechanism in health and disease. Moreover, a new concept is emerging from studies of extracellular protein phosphorylation: in cells where ATP is stored within secretory vesicles and released by exocytosis upon cell-stimulation, phosphorylation of extracellular proteins can operate as a messenger operating uniquely in signaling pathways responsible for long-term cellular adaptation. Here, we highlight new concepts that arise from this research, and discuss translation of the findings into clinical applications such as development of diagnostic disease markers and next-generation drugs.
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Affiliation(s)
| | | | - Bjorn R Olsen
- Department of Developmental Biology, Harvard School of Dental Medicine, 188 Longwood Avenue, Boston, MA 02115, USA.
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124
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Kummer MP, Heneka MT. Truncated and modified amyloid-beta species. ALZHEIMERS RESEARCH & THERAPY 2014; 6:28. [PMID: 25031638 PMCID: PMC4055046 DOI: 10.1186/alzrt258] [Citation(s) in RCA: 218] [Impact Index Per Article: 21.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Alzheimer’s disease pathology is closely connected to the processing of the amyloid precursor protein (APP) resulting in the formation of a variety of amyloid-beta (Aβ) peptides. They are found as insoluble aggregates in senile plaques, the histopathological hallmark of the disease. These peptides are also found in soluble, mostly monomeric and dimeric, forms in the interstitial and cerebrospinal fluid. Due to the combination of several enzymatic activities during APP processing, Aβ peptides exist in multiple isoforms possessing different N-termini and C-termini. These peptides include, to a certain extent, part of the juxtamembrane and transmembrane domain of APP. Besides differences in size, post-translational modifications of Aβ – including oxidation, phosphorylation, nitration, racemization, isomerization, pyroglutamylation, and glycosylation – generate a plethora of peptides with different physiological and pathological properties that may modulate disease progression.
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Affiliation(s)
- Markus P Kummer
- Department of Neurology, University Hospital Bonn, Sigmund-Freud-Strasse 25, 53127 Bonn, Germany
| | - Michael T Heneka
- Department of Neurology, University Hospital Bonn, Sigmund-Freud-Strasse 25, 53127 Bonn, Germany ; German Center for Neurodegenerative Diseases (DZNE), Holbeinstrasse 15, 53117 Bonn, Germany
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125
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Hubin E, van Nuland NAJ, Broersen K, Pauwels K. Transient dynamics of Aβ contribute to toxicity in Alzheimer's disease. Cell Mol Life Sci 2014; 71:3507-21. [PMID: 24803005 PMCID: PMC4143600 DOI: 10.1007/s00018-014-1634-z] [Citation(s) in RCA: 75] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2014] [Revised: 04/15/2014] [Accepted: 04/22/2014] [Indexed: 12/20/2022]
Abstract
The aggregation and deposition of the amyloid-β peptide (Aβ) in the brain has been linked with neuronal death, which progresses in the diagnostic and pathological signs of Alzheimer’s disease (AD). The transition of an unstructured monomeric peptide into self-assembled and more structured aggregates is the crucial conversion from what appears to be a harmless polypeptide into a malignant form that causes synaptotoxicity and neuronal cell death. Despite efforts to identify the toxic form of Aβ, the development of effective treatments for AD is still limited by the highly transient and dynamic nature of interconverting forms of Aβ. The variability within the in vivo “pool” of different Aβ peptides is another complicating factor. Here we review the dynamical interplay between various components that influence the heterogeneous Aβ system, from intramolecular Aβ flexibility to intermolecular dynamics between various Aβ alloforms and external factors. The complex dynamics of Aβ contributes to the causative role of Aβ in the pathogenesis of AD.
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Affiliation(s)
- E Hubin
- Nanobiophysics Group, MIRA Institute for Biomedical Technology and Technical Medicine, Faculty of Science and Technology, University of Twente, 7500 AE, Enschede, The Netherlands
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126
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Mittag JJ, Milani S, Walsh DM, Rädler JO, McManus JJ. Simultaneous measurement of a range of particle sizes during Aβ1-42 fibrillogenesis quantified using fluorescence correlation spectroscopy. Biochem Biophys Res Commun 2014; 448:195-9. [PMID: 24769478 DOI: 10.1016/j.bbrc.2014.04.088] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2014] [Accepted: 04/17/2014] [Indexed: 01/15/2023]
Abstract
Low molecular weight oligomers of amyloid beta (Aβ) are important drivers of Alzheimer's disease. A decrease in Aβ monomer levels in human cerebrospinal fluid (CSF) is observed in Alzheimers' patients and is a robust biomarker of the disease. It has been suggested that the decrease in monomer levels in CSF is due to the formation of Aβ oligomers. A robust technique capable of identifying Aβ oligomers in CSF is therefore desirable. We have used fluorescence correlation spectroscopy and a five Gaussian distribution model (5GDM) to monitor the aggregation of Aβ1-42 in sodium phosphate buffer and in artificial cerebrospinal fluid (ACSF). In buffer, several different sized components (monomer, oligomers, protofibrils and fibrils) can be identified simultaneously using 5GDM. In ACSF, the faster kinetics of fibrillogenesis leads to the formation of fibrils on very short timescales. This analysis method can also be used to monitor the aggregation of other proteins, nanoparticles or colloids, even in complex biological fluids.
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Affiliation(s)
- Judith J Mittag
- Ludwig-Maximilians-Universität, Fakultät für Physik & CeNS, Geschwister-Scholl-Platz 1, 80539 München, Germany.
| | - Silvia Milani
- Ludwig-Maximilians-Universität, Fakultät für Physik & CeNS, Geschwister-Scholl-Platz 1, 80539 München, Germany.
| | - Dominic M Walsh
- Laboratory for Neurodegenerative Research, Center for Neurologic Diseases, Brigham & Women's Hospital, Harvard Institutes of Medicine, Boston, MA 02115, USA.
| | - Joachim O Rädler
- Ludwig-Maximilians-Universität, Fakultät für Physik & CeNS, Geschwister-Scholl-Platz 1, 80539 München, Germany.
| | - Jennifer J McManus
- Department of Chemistry, National University of Ireland Maynooth, Maynooth, Co. Kildare, Ireland.
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127
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Rezaei-Ghaleh N, Amininasab M, Giller K, Kumar S, Stündl A, Schneider A, Becker S, Walter J, Zweckstetter M. Turn Plasticity Distinguishes Different Modes of Amyloid-β Aggregation. J Am Chem Soc 2014; 136:4913-9. [DOI: 10.1021/ja411707y] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Nasrollah Rezaei-Ghaleh
- German Center for Neurodegenerative Diseases (DZNE), 37077 Göttingen, Germany
- Department
for NMR-based Structural Biology, Max Planck Institute for Biophysical Chemistry, 37077 Göttingen, Germany
| | - Mehriar Amininasab
- Department
of Cell
and Molecular Biology, School of Biology, College of Science, University of Tehran, Tehran, Iran
| | - Karin Giller
- Department
for NMR-based Structural Biology, Max Planck Institute for Biophysical Chemistry, 37077 Göttingen, Germany
| | - Sathish Kumar
- Department
of Neurology, University of Bonn, 53127 Bonn, Germany
| | - Anne Stündl
- Department
of Psychiatry and Psychotherapy, University Medicine Göttingen, 37075 Göttingen, Germany
| | - Anja Schneider
- German Center for Neurodegenerative Diseases (DZNE), 37077 Göttingen, Germany
- Center for Nanoscale
Microscopy and Molecular Physiology of the Brain, University Medical
Center, University of Göttingen, 37073 Göttingen, Germany
- Department
of Psychiatry and Psychotherapy, University Medicine Göttingen, 37075 Göttingen, Germany
- Max Planck Institute for Experimental Medicine, 37075 Göttingen, Germany
| | - Stefan Becker
- Department
for NMR-based Structural Biology, Max Planck Institute for Biophysical Chemistry, 37077 Göttingen, Germany
| | - Jochen Walter
- Department
of Neurology, University of Bonn, 53127 Bonn, Germany
| | - Markus Zweckstetter
- German Center for Neurodegenerative Diseases (DZNE), 37077 Göttingen, Germany
- Department
for NMR-based Structural Biology, Max Planck Institute for Biophysical Chemistry, 37077 Göttingen, Germany
- Center for Nanoscale
Microscopy and Molecular Physiology of the Brain, University Medical
Center, University of Göttingen, 37073 Göttingen, Germany
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128
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Rijal Upadhaya A, Kosterin I, Kumar S, von Arnim CAF, Yamaguchi H, Fändrich M, Walter J, Thal DR. Biochemical stages of amyloid-β peptide aggregation and accumulation in the human brain and their association with symptomatic and pathologically preclinical Alzheimer’s disease. Brain 2014; 137:887-903. [PMID: 24519982 DOI: 10.1093/brain/awt362] [Citation(s) in RCA: 120] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Affiliation(s)
- Ajeet Rijal Upadhaya
- 1 Laboratory of Neuropathology, Institute of Pathology, Centre for Clinical Research at the University of Ulm, Ulm, Germany
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129
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Kulikova AA, Tsvetkov PO, Indeykina MI, Popov IA, Zhokhov SS, Golovin AV, Polshakov VI, Kozin SA, Nudler E, Makarov AA. Phosphorylation of Ser8 promotes zinc-induced dimerization of the amyloid-β metal-binding domain. ACTA ACUST UNITED AC 2014; 10:2590-6. [DOI: 10.1039/c4mb00332b] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Phosphorylation of Ser8 leads to the formation of a new Zn2+ binding site and promotes zinc-induced dimerization of Aβ(1–16).
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Affiliation(s)
- Alexandra A. Kulikova
- Engelhardt Institute of Molecular Biology
- Russian Academy of Sciences
- 119991 Moscow, Russia
| | - Philipp O. Tsvetkov
- Engelhardt Institute of Molecular Biology
- Russian Academy of Sciences
- 119991 Moscow, Russia
| | - Maria I. Indeykina
- Engelhardt Institute of Molecular Biology
- Russian Academy of Sciences
- 119991 Moscow, Russia
- Emanuel Institute of Biochemical Physics
- Russian Academy of Sciences
| | - Igor A. Popov
- Emanuel Institute of Biochemical Physics
- Russian Academy of Sciences
- 119334 Moscow, Russia
| | - Sergey S. Zhokhov
- Faculty of Fundamental Medicine
- M.V. Lomonosov Moscow State University
- 119191 Moscow, Russia
| | - Andrey V. Golovin
- Bioengineering and Bioinformatics Department
- M.V. Lomonosov Moscow State University
- 119991 Moscow, Russia
| | - Vladimir I. Polshakov
- Faculty of Fundamental Medicine
- M.V. Lomonosov Moscow State University
- 119191 Moscow, Russia
| | - Sergey A. Kozin
- Engelhardt Institute of Molecular Biology
- Russian Academy of Sciences
- 119991 Moscow, Russia
- Orekhovich Institute of Biomedical Chemistry
- Russian Academy of Medical Sciences
| | - Evgeny Nudler
- Howard Hughes Medical Institute
- New York University School of Medicine
- New York, USA
| | - Alexander A. Makarov
- Engelhardt Institute of Molecular Biology
- Russian Academy of Sciences
- 119991 Moscow, Russia
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130
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Rijal Upadhaya A, Scheibe F, Kosterin I, Abramowski D, Gerth J, Kumar S, Liebau S, Yamaguchi H, Walter J, Staufenbiel M, Thal DR. The type of Aβ-related neuronal degeneration differs between amyloid precursor protein (APP23) and amyloid β-peptide (APP48) transgenic mice. Acta Neuropathol Commun 2013; 1:77. [PMID: 24252227 PMCID: PMC4046770 DOI: 10.1186/2051-5960-1-77] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2013] [Accepted: 11/06/2013] [Indexed: 12/16/2022] Open
Abstract
Background The deposition of the amyloid β-peptide (Aβ) in the brain is one of the hallmarks of Alzheimer’s disease (AD). It is not yet clear whether Aβ always leads to similar changes or whether it induces different features of neurodegeneration in relation to its intra- and/or extracellular localization or to its intracellular trafficking routes. To address this question, we have analyzed two transgenic mouse models: APP48 and APP23 mice. The APP48 mouse expresses Aβ1-42 with a signal sequence in neurons. These animals produce intracellular Aβ independent of amyloid precursor protein (APP) but do not develop extracellular Aβ plaques. The APP23 mouse overexpresses human APP with the Swedish mutation (KM670/671NL) in neurons and produces APP-derived extracellular Aβ plaques and intracellular Aβ aggregates. Results Tracing of commissural neurons in layer III of the frontocentral cortex with the DiI tracer revealed no morphological signs of dendritic degeneration in APP48 mice compared to littermate controls. In contrast, the dendritic tree of highly ramified commissural frontocentral neurons was altered in 15-month-old APP23 mice. The density of asymmetric synapses in the frontocentral cortex was reduced in 3- and 15-month-old APP23 but not in 3- and 18-month-old APP48 mice. Frontocentral neurons of 18-month-old APP48 mice showed an increased proportion of altered mitochondria in the soma compared to wild type and APP23 mice. Aβ was often seen in the membrane of neuronal mitochondria in APP48 mice at the ultrastructural level. Conclusions These results indicate that APP-independent intracellular Aβ accumulation in APP48 mice is not associated with dendritic and neuritic degeneration but with mitochondrial alterations whereas APP-derived extra- and intracellular Aβ pathology in APP23 mice is linked to dendrite degeneration and synapse loss independent of obvious mitochondrial alterations. Thus, Aβ aggregates in APP23 and APP48 mice induce neurodegeneration presumably by different mechanisms and APP-related production of Aβ may, thereby, play a role for the degeneration of neurites and synapses. Electronic supplementary material The online version of this article (doi:10.1186/2051-5960-1-77) contains supplementary material, which is available to authorized users.
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131
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Evidence for prion-like mechanisms in several neurodegenerative diseases: potential implications for immunotherapy. Clin Dev Immunol 2013; 2013:473706. [PMID: 24228054 PMCID: PMC3817797 DOI: 10.1155/2013/473706] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2013] [Revised: 06/11/2013] [Accepted: 07/02/2013] [Indexed: 12/12/2022]
Abstract
Transmissible spongiform encephalopathies (TSEs) are fatal, untreatable neurodegenerative diseases. While the impact of TSEs on human health is relatively minor, these diseases are having a major influence on how we view, and potentially treat, other more common neurodegenerative disorders. Until recently, TSEs encapsulated a distinct category of neurodegenerative disorder, exclusive in their defining characteristic of infectivity. It now appears that similar mechanisms of self-propagation may underlie other proteinopathies such as Alzheimer's disease, Parkinson's disease, Amyotrophic lateral sclerosis, and Huntington's disease. This link is of scientific interest and potential therapeutic importance as this route of self-propagation offers conceptual support and guidance for vaccine development efforts. Specifically, the existence of a pathological, self-promoting isoform offers a rational vaccine target. Here, we review the evidence of prion-like mechanisms within a number of common neurodegenerative disorders and speculate on potential implications and opportunities for vaccine development.
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132
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Bouter Y, Dietrich K, Wittnam JL, Rezaei-Ghaleh N, Pillot T, Papot-Couturier S, Lefebvre T, Sprenger F, Wirths O, Zweckstetter M, Bayer TA. N-truncated amyloid β (Aβ) 4-42 forms stable aggregates and induces acute and long-lasting behavioral deficits. Acta Neuropathol 2013; 126:189-205. [PMID: 23685882 PMCID: PMC3722453 DOI: 10.1007/s00401-013-1129-2] [Citation(s) in RCA: 134] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2013] [Revised: 05/08/2013] [Accepted: 05/09/2013] [Indexed: 12/30/2022]
Abstract
N-truncated Aβ4-42 is highly abundant in Alzheimer disease (AD) brain and was the first Aβ peptide discovered in AD plaques. However, a possible role in AD aetiology has largely been neglected. In the present report, we demonstrate that Aβ4-42 rapidly forms aggregates possessing a high aggregation propensity in terms of monomer consumption and oligomer formation. Short-term treatment of primary cortical neurons indicated that Aβ4-42 is as toxic as pyroglutamate Aβ3-42 and Aβ1-42. In line with these findings, treatment of wildtype mice using intraventricular Aβ injection induced significant working memory deficits with Aβ4-42, pyroglutamate Aβ3-42 and Aβ1-42. Transgenic mice expressing Aβ4-42 (Tg4-42 transgenic line) developed a massive CA1 pyramidal neuron loss in the hippocampus. The hippocampus-specific expression of Aβ4-42 correlates well with age-dependent spatial reference memory deficits assessed by the Morris water maze test. Our findings indicate that N-truncated Aβ4-42 triggers acute and long-lasting behavioral deficits comparable to AD typical memory dysfunction.
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Affiliation(s)
- Yvonne Bouter
- Division of Molecular Psychiatry, Georg-August-University Goettingen, University Medicine Goettingen, von-Siebold-Strasse 5, 37075 Goettingen, Germany
| | - Katharina Dietrich
- Division of Molecular Psychiatry, Georg-August-University Goettingen, University Medicine Goettingen, von-Siebold-Strasse 5, 37075 Goettingen, Germany
| | - Jessica L. Wittnam
- Division of Molecular Psychiatry, Georg-August-University Goettingen, University Medicine Goettingen, von-Siebold-Strasse 5, 37075 Goettingen, Germany
| | - Nasrollah Rezaei-Ghaleh
- Department for NMR-based Structural Biology, Max Planck Institute for Biophysical Chemistry, 37077 Goettingen, Germany
| | | | | | | | - Frederick Sprenger
- Division of Molecular Psychiatry, Georg-August-University Goettingen, University Medicine Goettingen, von-Siebold-Strasse 5, 37075 Goettingen, Germany
| | - Oliver Wirths
- Division of Molecular Psychiatry, Georg-August-University Goettingen, University Medicine Goettingen, von-Siebold-Strasse 5, 37075 Goettingen, Germany
| | - Markus Zweckstetter
- German Center for Neurodegenerative Diseases (DZNE), 37077 Göttingen, Germany
- Department for NMR-based Structural Biology, Max Planck Institute for Biophysical Chemistry, 37077 Goettingen, Germany
| | - Thomas A. Bayer
- Division of Molecular Psychiatry, Georg-August-University Goettingen, University Medicine Goettingen, von-Siebold-Strasse 5, 37075 Goettingen, Germany
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133
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Peripherally Applied Synthetic Peptide isoAsp7-Aβ(1-42) Triggers Cerebral β-Amyloidosis. Neurotox Res 2013; 24:370-6. [DOI: 10.1007/s12640-013-9399-y] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2013] [Revised: 04/29/2013] [Accepted: 05/02/2013] [Indexed: 12/25/2022]
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134
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Kumar S, Wirths O, Theil S, Gerth J, Bayer TA, Walter J. Early intraneuronal accumulation and increased aggregation of phosphorylated Abeta in a mouse model of Alzheimer's disease. Acta Neuropathol 2013; 125:699-709. [PMID: 23525537 DOI: 10.1007/s00401-013-1107-8] [Citation(s) in RCA: 71] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2013] [Revised: 03/06/2013] [Accepted: 03/09/2013] [Indexed: 12/13/2022]
Abstract
The progressive accumulation of extracellular amyloid plaques in the brain is a common hallmark of Alzheimer's disease (AD). We recently identified a novel species of Aβ phosphorylated at serine residue 8 with increased propensity to form toxic aggregates as compared to non-phosphorylated species. The age-dependent analysis of Aβ depositions using novel monoclonal phosphorylation-state specific antibodies revealed that phosphorylated Aβ variants accumulate first inside of neurons in a mouse model of AD already at 2 month of age. At higher ages, phosphorylated Aβ is also abundantly detected in extracellular plaques. Besides a large overlap in the spatiotemporal deposition of phosphorylated and non-phosphorylated Aβ species, fractionized extraction of Aβ from brains revealed an increased accumulation of phosphorylated Aβ in oligomeric assemblies as compared to non-phosphorylated Aβ in vivo. Thus, phosphorylated Aβ could represent an important species in the formation and stabilization of neurotoxic aggregates, and might be targeted for AD therapy and diagnosis.
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Affiliation(s)
- Sathish Kumar
- Department of Neurology, University of Bonn, 53127, Bonn, Germany
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135
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Yalak G, Vogel V. Extracellular phosphorylation and phosphorylated proteins: not just curiosities but physiologically important. Sci Signal 2012; 5:re7. [PMID: 23250399 DOI: 10.1126/scisignal.2003273] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Mining of the literature and high-throughput mass spectrometry data from both healthy and diseased tissues and from body fluids reveals evidence that various extracellular proteins can exist in phosphorylated states. Extracellular kinases and phosphatases (ectokinases and ectophosphatases) are active in extracellular spaces during times of sufficiently high concentrations of adenosine triphosphate. There is evidence for a role of extracellular phosphorylation in various physiological functions, including blood coagulation, immune cell activation, and the formation of neuronal networks. Ectokinase activity is increased in some diseases, including cancer, Alzheimer's disease, and some microbial infections. We summarize the literature supporting the physiological and pathological roles of extracellularly localized protein kinases, protein phosphatases, and phosphorylated proteins and provide an analysis of the available mass spectrometry data to annotate potential extracellular phosphorylated proteins.
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Affiliation(s)
- Garif Yalak
- Department of Health Sciences and Technology, ETH Zurich, Wolfgang Pauli Strasse 10, HCI F443, CH-8093 Zurich, Switzerland
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136
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Alzheimer's disease Aβ assemblies mediating rapid disruption of synaptic plasticity and memory. Mol Brain 2012; 5:25. [PMID: 22805374 PMCID: PMC3502131 DOI: 10.1186/1756-6606-5-25] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2012] [Accepted: 06/22/2012] [Indexed: 01/24/2023] Open
Abstract
Alzheimer’s disease (AD) is characterized by episodic memory impairment that often precedes clinical diagnosis by many years. Probing the mechanisms of such impairment may provide much needed means of diagnosis and therapeutic intervention at an early, pre-dementia, stage. Prior to the onset of significant neurodegeneration, the structural and functional integrity of synapses in mnemonic circuitry is severely compromised in the presence of amyloidosis. This review examines recent evidence evaluating the role of amyloid-ß protein (Aβ) in causing rapid disruption of synaptic plasticity and memory impairment. We evaluate the relative importance of different sizes and conformations of Aβ, including monomer, oligomer, protofibril and fibril. We pay particular attention to recent controversies over the relevance to the pathophysiology of AD of different water soluble Aβ aggregates and the importance of cellular prion protein in mediating their effects. Current data are consistent with the view that both low-n oligomers and larger soluble assemblies present in AD brain, some of them via a direct interaction with cellular prion protein, cause synaptic memory failure. At the two extremes of aggregation, monomers and fibrils appear to act in vivo both as sources and sinks of certain metastable conformations of soluble aggregates that powerfully disrupt synaptic plasticity. The same principle appears to apply to other synaptotoxic amyloidogenic proteins including tau, α-synuclein and prion protein.
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137
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Invernizzi G, Papaleo E, Sabate R, Ventura S. Protein aggregation: mechanisms and functional consequences. Int J Biochem Cell Biol 2012; 44:1541-54. [PMID: 22713792 DOI: 10.1016/j.biocel.2012.05.023] [Citation(s) in RCA: 98] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2012] [Revised: 05/09/2012] [Accepted: 05/27/2012] [Indexed: 12/31/2022]
Abstract
Understanding the mechanisms underlying protein misfolding and aggregation has become a central issue in biology and medicine. Compelling evidence show that the formation of amyloid aggregates has a negative impact in cell function and is behind the most prevalent human degenerative disorders, including Alzheimer's Parkinson's and Huntington's diseases or type 2 diabetes. Surprisingly, the same type of macromolecular assembly is used for specialized functions by different organisms, from bacteria to human. Here we address the conformational properties of these aggregates, their formation pathways, their role in human diseases, their functional properties and how bioinformatics tools might be of help to study these protein assemblies.
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Affiliation(s)
- Gaetano Invernizzi
- Dipartimento di Biotecnologie e Bioscienze, Università di Milano-Bicocca, Milan, Italy
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138
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Abstract
Amyloid fibers and oligomers are associated with a great variety of human diseases including Alzheimer's disease and the prion conditions. Here we attempt to connect recent discoveries on the molecular properties of proteins in the amyloid state with observations about pathological tissues and disease states. We summarize studies of structure and nucleation of amyloid and relate these to observations on amyloid polymorphism, prion strains, coaggregation of pathogenic proteins in tissues, and mechanisms of toxicity and transmissibility. Molecular studies have also led to numerous strategies for biological and chemical interventions against amyloid diseases.
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Affiliation(s)
- David Eisenberg
- Howard Hughes Medical Institute, Department of Biological Chemistry, University of California, Los Angeles, Los Angeles CA 90095-1570, USA.
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139
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Benilova I, Karran E, De Strooper B. The toxic Aβ oligomer and Alzheimer's disease: an emperor in need of clothes. Nat Neurosci 2012; 15:349-57. [DOI: 10.1038/nn.3028] [Citation(s) in RCA: 1435] [Impact Index Per Article: 119.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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140
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Kumar S, Singh S, Hinze D, Josten M, Sahl HG, Siepmann M, Walter J. Phosphorylation of amyloid-β peptide at serine 8 attenuates its clearance via insulin-degrading and angiotensin-converting enzymes. J Biol Chem 2012; 287:8641-51. [PMID: 22267728 DOI: 10.1074/jbc.m111.279133] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Accumulation of amyloid-β peptides (Aβ) in the brain is a common pathological feature of Alzheimer disease (AD). Aggregates of Aβ are neurotoxic and appear to be critically involved in the neurodegeneration during AD pathogenesis. Accumulation of Aβ could be caused by increased production, as indicated by several mutations in the amyloid precursor protein or the γ-secretase components presenilin-1 and presenilin-2 that cause familial early-onset AD. However, recent data also indicate a decreased clearance rate of Aβ in AD brains. We recently demonstrated that Aβ undergoes phosphorylation by extracellular or cell surface-localized protein kinase A, leading to increased aggregation. Here, we provide evidence that phosphorylation of monomeric Aβ at Ser-8 also decreases its clearance by microglial cells. By using mass spectrometry, we demonstrate that phosphorylation at Ser-8 inhibited the proteolytic degradation of monomeric Aβ by the insulin-degrading enzyme, a major Aβ-degrading enzyme released from microglial cells. Phosphorylation also decreased the degradation of Aβ by the angiotensin-converting enzyme. In contrast, Aβ degradation by plasmin was largely unaffected by phosphorylation. Thus, phosphorylation of Aβ could play a dual role in Aβ metabolism. It decreases its proteolytic clearance and also promotes its aggregation. The inhibition of extracellular Aβ phosphorylation, stimulation of protease expression and/or their proteolytic activity could be explored to promote Aβ degradation in AD therapy or prevention.
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Affiliation(s)
- Sathish Kumar
- Department of Neurology, University of Bonn, 53127 Bonn, Germany
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141
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Heat shock transcription factor 1 as a therapeutic target in neurodegenerative diseases. Nat Rev Drug Discov 2011; 10:930-44. [PMID: 22129991 DOI: 10.1038/nrd3453] [Citation(s) in RCA: 206] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Neurodegenerative diseases such as Alzheimer's disease, Parkinson's disease, Huntington's disease, amyotrophic lateral sclerosis and prion-based neurodegeneration are associated with the accumulation of misfolded proteins, resulting in neuronal dysfunction and cell death. However, current treatments for these diseases predominantly address disease symptoms, rather than the underlying protein misfolding and cell death, and are not able to halt or reverse the degenerative process. Studies in cell culture, fruitfly, worm and mouse models of protein misfolding-based neurodegenerative diseases indicate that enhancing the protein-folding capacity of cells, via elevated expression of chaperone proteins, has therapeutic potential. Here, we review advances in strategies to harness the power of the natural cellular protein-folding machinery through pharmacological activation of heat shock transcription factor 1--the master activator of chaperone protein gene expression--to treat neurodegenerative diseases.
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142
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Roberts BR, Ryan TM, Bush AI, Masters CL, Duce JA. The role of metallobiology and amyloid-β peptides in Alzheimer’s disease. J Neurochem 2011; 120 Suppl 1:149-166. [DOI: 10.1111/j.1471-4159.2011.07500.x] [Citation(s) in RCA: 199] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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143
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Jawhar S, Wirths O, Bayer TA. Pyroglutamate amyloid-β (Aβ): a hatchet man in Alzheimer disease. J Biol Chem 2011; 286:38825-32. [PMID: 21965666 DOI: 10.1074/jbc.r111.288308] [Citation(s) in RCA: 165] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Pyroglutamate-modified amyloid-β (Aβ(pE3)) peptides are gaining considerable attention as potential key participants in the pathology of Alzheimer disease (AD) due to their abundance in AD brain, high aggregation propensity, stability, and cellular toxicity. Transgenic mice that produce high levels of Aβ(pE3-42) show severe neuron loss. Recent in vitro and in vivo experiments have proven that the enzyme glutaminyl cyclase catalyzes the formation of Aβ(pE3). In this minireview, we summarize the current knowledge on Aβ(pE3), discussing its discovery, biochemical properties, molecular events determining formation, prevalence in the brains of AD patients, Alzheimer mouse models, and potential as a target for therapy and as a diagnostic marker.
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Affiliation(s)
- Sadim Jawhar
- Department of Molecular Psychiatry, Georg-August-University Göttingen, University Medicine Göttingen, 37075 Göttingen, Germany
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144
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Kumar S, Walter J. Phosphorylation of amyloid beta (Aβ) peptides - a trigger for formation of toxic aggregates in Alzheimer's disease. Aging (Albany NY) 2011; 3:803-12. [PMID: 21869458 PMCID: PMC3184981 DOI: 10.18632/aging.100362] [Citation(s) in RCA: 108] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/13/2023]
Abstract
Alzheimer's disease (AD) is the most common form of dementia and associated with the progressive accumulation of amyloid β-peptides (Aβ) in form of extracellular amyloid plaques in the human brain. A critical role of Aβ in the pathogenesis of AD is strongly supported by gene mutations that cause early-onset familial forms of the disease. Such mutations have been identified in the APP gene itself and in presenilin 1 and 2. Importantly, all the identified mutations commonly lead to early deposition of extracellular plaques likely by increasing the generation and/or aggregation of Aβ. However, such mutations are very rare and molecular mechanisms that might trigger aggregation and deposition of Aβ, in the most common late onset AD are largely unknown. We recently demonstrated that extracellular Aβ undergoes phosphorylation by a cell surface-localized or secreted form of protein kinase A. The phosphorylation of serine residue 8 promotes aggregation by stabilization of β-sheet conformation of Aβ and increased formation of oligomeric Aβ aggregates that represent nuclei for fibrillization. Phosphorylated Aβ was detected in the brains of transgenic mice and human AD brains and showed increased toxicity in Drosophila models as compared with non-phosphorylated Aβ. Together, these findings demonstrate a novel molecular mechanism that triggers aggregation and toxicity of Aβ. Thus, phosphorylation of Aβ could be relevant in the pathogenesis of late onset AD. The identification of extracellular protein kinase A should also stimulate pharmacological approaches to decrease Aβ phosphorylation in the therapy and/or prevention of AD.
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Affiliation(s)
- Sathish Kumar
- Department of Neurology, University of Bonn, 53127 Bonn, Germany
| | - Jochen Walter
- Department of Neurology, University of Bonn, 53127 Bonn, Germany
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