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Nilsson BL, Celebi Torabfam G, Dias CL. Peptide Self-Assembly into Amyloid Fibrils: Unbiased All-Atom Simulations. J Phys Chem B 2024; 128:3320-3328. [PMID: 38447080 DOI: 10.1021/acs.jpcb.3c07861] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/08/2024]
Abstract
Protein self-assembly plays an important role in biological systems, accounting for the formation of mesoscopic structures that can be highly symmetric as in the capsid of viruses or disordered as in molecular condensates or exhibit a one-dimensional fibrillar morphology as in amyloid fibrils. Deposits of the latter in tissues of individuals with degenerative diseases like Alzheimer's and Parkinson's has motivated extensive efforts to understand the sequence of molecular events accounting for their formation. These studies aim to identify on-pathway intermediates that may be the targets for therapeutic intervention. This detailed knowledge of fibril formation remains obscure, in part due to challenges with experimental analyses of these processes. However, important progress is being achieved for short amyloid peptides due to advances in our ability to perform completely unbiased all-atom simulations of the self-assembly process. This perspective discusses recent developments, their implications, and the hurdles that still need to be overcome to further advance the field.
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Affiliation(s)
- Bradley L Nilsson
- Department of Chemistry, University of Rochester, Rochester, New York 14627-0216, United States
- Materials Science Program, University of Rochester, Rochester, New York 14627-0216, United States
| | - Gizem Celebi Torabfam
- Department of Physics, New Jersey Institute of Technology, Newark, New Jersey 07102-1982, United States
| | - Cristiano L Dias
- Department of Physics, New Jersey Institute of Technology, Newark, New Jersey 07102-1982, United States
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2
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Balczon R, Lin MT, Voth S, Nelson AR, Schupp JC, Wagener BM, Pittet JF, Stevens T. Lung endothelium, tau, and amyloids in health and disease. Physiol Rev 2024; 104:533-587. [PMID: 37561137 PMCID: PMC11281824 DOI: 10.1152/physrev.00006.2023] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Revised: 06/26/2023] [Accepted: 08/04/2023] [Indexed: 08/11/2023] Open
Abstract
Lung endothelia in the arteries, capillaries, and veins are heterogeneous in structure and function. Lung capillaries in particular represent a unique vascular niche, with a thin yet highly restrictive alveolar-capillary barrier that optimizes gas exchange. Capillary endothelium surveys the blood while simultaneously interpreting cues initiated within the alveolus and communicated via immediately adjacent type I and type II epithelial cells, fibroblasts, and pericytes. This cell-cell communication is necessary to coordinate the immune response to lower respiratory tract infection. Recent discoveries identify an important role for the microtubule-associated protein tau that is expressed in lung capillary endothelia in the host-pathogen interaction. This endothelial tau stabilizes microtubules necessary for barrier integrity, yet infection drives production of cytotoxic tau variants that are released into the airways and circulation, where they contribute to end-organ dysfunction. Similarly, beta-amyloid is produced during infection. Beta-amyloid has antimicrobial activity, but during infection it can acquire cytotoxic activity that is deleterious to the host. The production and function of these cytotoxic tau and amyloid variants are the subject of this review. Lung-derived cytotoxic tau and amyloid variants are a recently discovered mechanism of end-organ dysfunction, including neurocognitive dysfunction, during and in the aftermath of infection.
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Affiliation(s)
- Ron Balczon
- Department of Biochemistry and Molecular Biology, University of South Alabama, Mobile, Alabama, United States
- Center for Lung Biology, University of South Alabama, Mobile, Alabama, United States
| | - Mike T Lin
- Department of Physiology and Cell Biology, University of South Alabama, Mobile, Alabama, United States
- Center for Lung Biology, University of South Alabama, Mobile, Alabama, United States
| | - Sarah Voth
- Department of Cell Biology and Physiology, Edward Via College of Osteopathic Medicine, Monroe, Louisiana, United States
| | - Amy R Nelson
- Department of Physiology and Cell Biology, University of South Alabama, Mobile, Alabama, United States
- Center for Lung Biology, University of South Alabama, Mobile, Alabama, United States
| | - Jonas C Schupp
- Pulmonary and Critical Care Medicine, Department of Internal Medicine, Yale University, New Haven, Connecticut, United States
- Department of Respiratory Medicine, Hannover Medical School, Hannover, Germany
- German Center for Lung Research (DZL), Hannover, Germany
| | - Brant M Wagener
- Department of Anesthesiology and Perioperative Medicine, University of Alabama-Birmingham, Birmingham, Alabama, United States
| | - Jean-Francois Pittet
- Department of Anesthesiology and Perioperative Medicine, University of Alabama-Birmingham, Birmingham, Alabama, United States
| | - Troy Stevens
- Department of Physiology and Cell Biology, University of South Alabama, Mobile, Alabama, United States
- Department of Internal Medicine, University of South Alabama, Mobile, Alabama, United States
- Center for Lung Biology, University of South Alabama, Mobile, Alabama, United States
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3
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Mohd Nor Ihsan NS, Abdul Sani SF, Looi LM, Pathmanathan D, Cheah PL, Chiew SF, Bradley DA. EDXRF and the relative presence of K, Ca, Fe and as in amyloidogenic tissues. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2024; 308:123743. [PMID: 38113556 DOI: 10.1016/j.saa.2023.123743] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2023] [Revised: 11/09/2023] [Accepted: 12/07/2023] [Indexed: 12/21/2023]
Abstract
Trace and minor elements play crucial roles in a variety of biological processes, including amyloid fibrils formation. Mechanisms include activation or inhibition of enzymatic reactions, competition between elements and metal proteins for binding positions, also changes to the permeability of cellular membranes. These may influence carcinogenic processes, with trace and minor element concentrations in normal and amyloid tissues potentially aiding in cancer diagnosis and etiology. With the analytical capability of the spectroscopic technique X-ray fluorescence (XRF), this can be used to detect and quantify the presence of elements in amyloid characterization, two of the trace elements known to be associated with amyloid fibrils. In present work, involving samples from a total of 22 subjects, samples of normal and amyloid-containing tissues of heart, kidney, thyroid, and other tissue organs were obtained, analyzed via energy-dispersive X-ray fluorescence (EDXRF). The elemental distribution of potassium (K), calcium (Ca), arsenic (As), and iron (Fe) was examined in both normal and amyloidogenic tissues using perpetual thin slices. In amyloidogenic tissues the levels of K, Ca, and Fe were found to be less than in corresponding normal tissues. Moreover, the presence of As was only observed in amyloidogenic samples; in a few cases in which there was an absence of As, amyloid samples were found to contain Fe. Analysis of arsenic in amyloid plaques has previously been difficult, often producing contradictory results. Using the present EDXRF facility we could distinguish between amyloidogenic and normal samples, with potential correlations in respect of the presence or concentration of specific elements.
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Affiliation(s)
- N S Mohd Nor Ihsan
- Department of Physics, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - S F Abdul Sani
- Department of Physics, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia.
| | - L M Looi
- Department of Pathology, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Dharini Pathmanathan
- Institute of Mathematical Sciences, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - P L Cheah
- Department of Pathology, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - S F Chiew
- Department of Pathology, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - D A Bradley
- Sunway University, Centre for Applied Physics and Radiation Technologies, Jalan Universiti, 46150 PJ, Malaysia; School of Mathematics and Physics, University of Surrey, Guildford GU2 7XH, UK
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4
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Přáda Brichtová E, Krupová M, Bouř P, Lindo V, Gomes Dos Santos A, Jackson SE. Glucagon-like peptide 1 aggregates into low-molecular-weight oligomers off-pathway to fibrillation. Biophys J 2023; 122:2475-2488. [PMID: 37138517 PMCID: PMC10323027 DOI: 10.1016/j.bpj.2023.04.027] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2022] [Revised: 01/04/2023] [Accepted: 04/27/2023] [Indexed: 05/05/2023] Open
Abstract
The physical stability of peptide-based drugs is of great interest to the pharmaceutical industry. Glucagon-like peptide 1 (GLP-1) is a 31-amino acid peptide hormone, the analogs of which are frequently used in the treatment of type 2 diabetes. We investigated the physical stability of GLP-1 and its C-terminal amide derivative, GLP-1-Am, both of which aggregate into amyloid fibrils. While off-pathway oligomers have been proposed to explain the unusual aggregation kinetics observed previously for GLP-1 under specific conditions, these oligomers have not been studied in any detail. Such states are important as they may represent potential sources of cytotoxicity and immunogenicity. Here, we identified and isolated stable, low-molecular-weight oligomers of GLP-1 and GLP-1-Am, using size-exclusion chromatography. Under the conditions studied, isolated oligomers were shown to be resistant to fibrillation or dissociation. These oligomers contain between two and five polypeptide chains and they have a highly disordered structure as indicated by a variety of spectroscopic techniques. They are highly stable with respect to time, temperature, or agitation despite their noncovalent character, which was established using liquid chromatography-mass spectrometry and sodium dodecyl sulfate-polyacrylamide gel electrophoresis. These results provide evidence of stable, low-molecular-weight oligomers that are formed by an off-pathway mechanism which competes with amyloid fibril formation.
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Affiliation(s)
- Eva Přáda Brichtová
- Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge, United Kingdom
| | - Monika Krupová
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences, Prague 6, Czech Republic; Hylleraas Centre for Quantum Molecular Sciences, Department of Chemistry, UiT The Arctic University of Norway, Tromsø, Norway
| | - Petr Bouř
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences, Prague 6, Czech Republic
| | - Viv Lindo
- AstraZeneca, Cambridge, United Kingdom
| | | | - Sophie E Jackson
- Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge, United Kingdom.
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Mohd Nor Ihsan NS, Abdul Sani SF, Looi LM, Cheah PL, Chiew SF, Pathmanathan D, Bradley DA. A review: Exploring the metabolic and structural characterisation of beta pleated amyloid fibril in human tissue using Raman spectrometry and SAXS. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2023:S0079-6107(23)00059-7. [PMID: 37307955 DOI: 10.1016/j.pbiomolbio.2023.06.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2023] [Revised: 05/12/2023] [Accepted: 06/09/2023] [Indexed: 06/14/2023]
Abstract
Amyloidosis is a deleterious condition caused by abnormal amyloid fibril build-up in living tissues. To date, 42 proteins that are linked to amyloid fibrils have been discovered. Amyloid fibril structure variation can affect the severity, progression rate, or clinical symptoms of amyloidosis. Since amyloid fibril build-up is the primary pathological basis for various neurodegenerative illnesses, characterization of these deadly proteins, particularly utilising optical techniques have been a focus. Spectroscopy techniques provide significant non-invasive platforms for the investigation of the structure and conformation of amyloid fibrils, offering a wide spectrum of analyses ranging from nanometric to micrometric size scales. Even though this area of study has been intensively explored, there still remain aspects of amyloid fibrillization that are not fully known, a matter hindering progress in treating and curing amyloidosis. This review aims to provide recent updates and comprehensive information on optical techniques for metabolic and proteomic characterization of β-pleated amyloid fibrils found in human tissue with thorough literature analysis of publications. Raman spectroscopy and SAXS are well established experimental methods for study of structural properties of biomaterials. With suitable models, they offer extended information for valid proteomic analysis under physiologically relevant conditions. This review points to evidence that despite limitations, these techniques are able to provide for the necessary output and proteomics indication in order to extrapolate the aetiology of amyloid fibrils for reliable diagnostic purposes. Our metabolic database may also contribute to elucidating the nature and function of the amyloid proteome in development and clearance of amyloid diseases.
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Affiliation(s)
- N S Mohd Nor Ihsan
- Department of Physics, Faculty of Science, University of Malaya, 50603, Kuala Lumpur, Malaysia
| | - S F Abdul Sani
- Department of Physics, Faculty of Science, University of Malaya, 50603, Kuala Lumpur, Malaysia.
| | - L M Looi
- Department of Pathology, Faculty of Medicine, University of Malaya, 50603, Kuala Lumpur, Malaysia
| | - P L Cheah
- Department of Pathology, Faculty of Medicine, University of Malaya, 50603, Kuala Lumpur, Malaysia
| | - S F Chiew
- Department of Pathology, Faculty of Medicine, University of Malaya, 50603, Kuala Lumpur, Malaysia
| | - Dharini Pathmanathan
- Institute of Mathematical Sciences, Faculty of Science, University of Malaya, 50603, Kuala Lumpur, Malaysia
| | - D A Bradley
- Centre for Applied Physics and Radiation Technologies, Sunway University, 46150 PJ, Malaysia; Department of Physics, School of Mathematics & Physics, University of Surrey, Guildford, GU2 7XH, UK
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6
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Muschol M, Hoyer W. Amyloid oligomers as on-pathway precursors or off-pathway competitors of fibrils. Front Mol Biosci 2023; 10:1120416. [PMID: 36845541 PMCID: PMC9947291 DOI: 10.3389/fmolb.2023.1120416] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Accepted: 01/27/2023] [Indexed: 02/11/2023] Open
Abstract
Amyloid Diseases involve the growth of disease specific proteins into amyloid fibrils and their deposition in protein plaques. Amyloid fibril formation is typically preceded by oligomeric intermediates. Despite significant efforts, the specific role fibrils or oligomers play in the etiology of any given amyloid disease remains controversial. In neurodegenerative disease, though, amyloid oligomers are widely considered critical contributors to disease symptoms. Aside from oligomers as inevitable on-pathway precursors of fibril formation, there is significant evidence for off-pathway oligomer formation competing with fibril growth. The distinct mechanisms and pathways of oligomer formation directly affect our understanding under which conditions oligomers emerge in vivo, and whether their formation is directly coupled to, or distinct from, amyloid fibril formation. In this review, we will discuss the basic energy landscapes underlying the formation of on-pathway vs. off-pathway oligomers, their relation to the related amyloid aggregation kinetics, and their resulting implications for disease etiology. We will review evidence on how differences in the local environment of amyloid assembly can dramatically shift the relative preponderance of oligomers vs. fibrils. Finally, we will comment on gaps in our knowledge of oligomer assembly, of their structure, and on how to assess their relevance to disease etiology.
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Affiliation(s)
- Martin Muschol
- Department of Physics, University of South Florida, Tampa, FL, United States,*Correspondence: Martin Muschol, ; Wolfgang Hoyer,
| | - Wolfgang Hoyer
- Institut für Physikalische Biologie, Heinrich-Heine-Universität, Düsseldorf, Germany,Institute of Biological Information Processing (IBI-7) and JuStruct, Jülich Center for Structural Biology, Forschungszentrum Jülich, Jülich, Germany,*Correspondence: Martin Muschol, ; Wolfgang Hoyer,
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7
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Effects of zinc and carnosine on aggregation kinetics of Amyloid-β40 peptide. Biochem Biophys Rep 2022; 32:101333. [PMID: 36105613 PMCID: PMC9464885 DOI: 10.1016/j.bbrep.2022.101333] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Revised: 07/15/2022] [Accepted: 08/21/2022] [Indexed: 11/24/2022] Open
Abstract
The accumulation and amyloid formation of amyloid-β (Aβ) peptides is closely associated with the pathology of Alzheimer's disease. The physiological environment wherein Aβ aggregation happens is crowded with a large variety of metal ions including Zn2+. In this study, we investigated the role of Zn2+ in regulating the aggregation kinetics of Aβ40 peptide. Our results show that Zn2+ can shift a typical single sigmoidal aggregation kinetics of Aβ40 to a biphasic aggregation process. Zn2+ aids in initiating the rapid self-assembly of monomers to form oligomeric intermediates, which further grow into amyloid fibrils in the first aggregation phase. The presence of Zn2+ also retards the appearance of the second aggregation phase in a concentration dependent manner. In addition, our results show that a natural dipeptide, carnosine, can greatly alleviate the effect of Zn2+ on Aβ aggregation kinetics, most likely by coordinating with the metal ion to form chelates. These results suggest a potential in vivo protective effect of carnosine against the cytotoxicity of Aβ by suppressing Zn2+-induced rapid formation of Aβ oligomers. Zn2+ shifts a typical single sigmoidal aggregation kinetics of Aβ40 to a biphasic process. Zn2+ facilitates the rapid formation oligomers in the first aggregation phase. Zn2+ retards the second aggregation phase in a concentration dependent manner. Carnosine greatly reduces the effect of Zn2+ on Aβ aggregation by coordinating with Zn2+.
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8
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Yuan M, Tang X, Han W. Anatomy and Formation Mechanisms of Early Amyloid-β Oligomers with Lateral Branching: Graph Network Analysis on Large-Scale Simulations. Chem Sci 2022; 13:2649-2660. [PMID: 35356670 PMCID: PMC8890322 DOI: 10.1039/d1sc06337e] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2021] [Accepted: 02/08/2022] [Indexed: 11/29/2022] Open
Abstract
Oligomeric amyloid-β aggregates (AβOs) effectively trigger Alzheimer's disease-related toxicity, generating great interest in understanding their structures and formation mechanisms. However, AβOs are heterogeneous and transient, making their structure and formation difficult to study. Here, we performed graph network analysis of tens of microsecond massive simulations of early amyloid-β (Aβ) aggregations at near-atomic resolution to characterize AβO structures with sizes up to 20-mers. We found that AβOs exhibit highly curvilinear, irregular shapes with occasional lateral branches, consistent with recent cryo-electron tomography experiments. We also found that Aβ40 oligomers were more likely to develop branches than Aβ42 oligomers, explaining an experimental observation that only Aβ40 was trapped in network-like aggregates and exhibited slower fibrillization kinetics. Moreover, AβO architecture dissection revealed that their curvilinear appearance is related to the local packing geometries of neighboring peptides and that Aβ40's greater branching ability originates from specific C-terminal interactions at branching interfaces. Finally, we demonstrate that whether Aβ oligomerization causes oligomers to elongate or to branch depends on the sizes and shapes of colliding aggregates. Collectively, this study provides bottom-up structural information for understanding early Aβ aggregation and AβO toxicity. Graph network analysis on large-scale simulations uncovers the differential branching behaviours of large Aβ40 and Aβ42 oligomers.![]()
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Affiliation(s)
- Miao Yuan
- State Key Laboratory of Chemical Oncogenomics, Guangdong Provincial Key Laboratory of Chemical Genomics, School of Chemical Biology and Biotechnology, Peking University Shenzhen Graduate School Shenzhen 518055 China
| | - Xuan Tang
- State Key Laboratory of Chemical Oncogenomics, Guangdong Provincial Key Laboratory of Chemical Genomics, School of Chemical Biology and Biotechnology, Peking University Shenzhen Graduate School Shenzhen 518055 China
| | - Wei Han
- State Key Laboratory of Chemical Oncogenomics, Guangdong Provincial Key Laboratory of Chemical Genomics, School of Chemical Biology and Biotechnology, Peking University Shenzhen Graduate School Shenzhen 518055 China
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9
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Vignon A, Salvador-Prince L, Lehmann S, Perrier V, Torrent J. Deconstructing Alzheimer's Disease: How to Bridge the Gap between Experimental Models and the Human Pathology? Int J Mol Sci 2021; 22:8769. [PMID: 34445475 PMCID: PMC8395727 DOI: 10.3390/ijms22168769] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Revised: 08/05/2021] [Accepted: 08/06/2021] [Indexed: 02/07/2023] Open
Abstract
Discovered more than a century ago, Alzheimer's disease (AD) is not only still present in our societies but has also become the most common dementia, with 50 million people worldwide affected by the disease. This number is expected to double in the next generation, and no cure is currently available to slow down or stop the disease progression. Recently, some advances were made due to the approval of the aducanumab treatment by the American Food and Drug Administration. The etiology of this human-specific disease remains poorly understood, and the mechanisms of its development have not been completely clarified. Several hypotheses concerning the molecular mechanisms of AD have been proposed, but the existing studies focus primarily on the two main markers of the disease: the amyloid β peptides, whose aggregation in the brain generates amyloid plaques, and the abnormally phosphorylated tau proteins, which are responsible for neurofibrillary tangles. These protein aggregates induce neuroinflammation and neurodegeneration, which, in turn, lead to cognitive and behavioral deficits. The challenge is, therefore, to create models that best reproduce this pathology. This review aims at gathering the different existing AD models developed in vitro, in cellulo, and in vivo. Many models have already been set up, but it is necessary to identify the most relevant ones for our investigations. The purpose of the review is to help researchers to identify the most pertinent disease models, from the most often used to the most recently generated and from simple to complex, explaining their specificities and giving concrete examples.
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Affiliation(s)
- Anaïs Vignon
- INM, University of Montpellier, INSERM, 34095 Montpellier, France; (A.V.); (L.S.-P.)
| | - Lucie Salvador-Prince
- INM, University of Montpellier, INSERM, 34095 Montpellier, France; (A.V.); (L.S.-P.)
| | - Sylvain Lehmann
- INM, University of Montpellier, INSERM, CHU Montpellier, 34095 Montpellier, France;
| | - Véronique Perrier
- INM, University of Montpellier, INSERM, CNRS, 34095 Montpellier, France
| | - Joan Torrent
- INM, University of Montpellier, INSERM, 34095 Montpellier, France; (A.V.); (L.S.-P.)
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10
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Kharkov BB, Podkorytov IS, Bondarev SA, Belousov MV, Salikov VA, Zhouravleva GA, Skrynnikov NR. The Role of Rotational Motion in Diffusion NMR Experiments on Supramolecular Assemblies: Application to Sup35NM Fibrils. Angew Chem Int Ed Engl 2021; 60:15445-15451. [PMID: 33891789 DOI: 10.1002/anie.202102408] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Revised: 04/19/2021] [Indexed: 11/08/2022]
Abstract
Pulsed-field gradient (PFG) NMR is an important tool for characterization of biomolecules and supramolecular assemblies. However, for micrometer-sized objects, such as amyloid fibrils, these experiments become difficult to interpret because in addition to translational diffusion they are also sensitive to rotational diffusion. We have constructed a mathematical theory describing the outcome of PFG NMR experiments on rod-like fibrils. To test its validity, we have studied the fibrils formed by Sup35NM segment of the prion protein Sup35. The interpretation of the PFG NMR data in this system is fully consistent with the evidence from electron microscopy. Contrary to some previously expressed views, the signals originating from disordered regions in the fibrils can be readily differentiated from the similar signals representing small soluble species (e.g. proteolytic fragments). This paves the way for diffusion-sorted NMR experiments on complex amyloidogenic samples.
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Affiliation(s)
- Boris B Kharkov
- Laboratory of Biomolecular NMR, St. Petersburg State University, 199034, St. Petersburg, Russia
| | - Ivan S Podkorytov
- Laboratory of Biomolecular NMR, St. Petersburg State University, 199034, St. Petersburg, Russia
| | - Stanislav A Bondarev
- Department of Genetics and Biotechnology, St. Petersburg State University, 199034, St. Petersburg, Russia
| | - Mikhail V Belousov
- Department of Genetics and Biotechnology, St. Petersburg State University, 199034, St. Petersburg, Russia.,Laboratory for Proteomics of Supra-Organismal Systems, All-Russia Research Institute for Agricultural Microbiology (ARRIAM), 196608, St. Petersburg, Russia
| | - Vladislav A Salikov
- Laboratory of Biomolecular NMR, St. Petersburg State University, 199034, St. Petersburg, Russia
| | - Galina A Zhouravleva
- Department of Genetics and Biotechnology, St. Petersburg State University, 199034, St. Petersburg, Russia
| | - Nikolai R Skrynnikov
- Laboratory of Biomolecular NMR, St. Petersburg State University, 199034, St. Petersburg, Russia.,Department of Chemistry, Purdue University, West Lafayette, IN, 47907, USA
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11
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Kharkov BB, Podkorytov IS, Bondarev SA, Belousov MV, Salikov VA, Zhouravleva GA, Skrynnikov NR. The Role of Rotational Motion in Diffusion NMR Experiments on Supramolecular Assemblies: Application to Sup35NM Fibrils. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202102408] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Boris B. Kharkov
- Laboratory of Biomolecular NMR St. Petersburg State University 199034 St. Petersburg Russia
| | - Ivan S. Podkorytov
- Laboratory of Biomolecular NMR St. Petersburg State University 199034 St. Petersburg Russia
| | - Stanislav A. Bondarev
- Department of Genetics and Biotechnology St. Petersburg State University 199034 St. Petersburg Russia
| | - Mikhail V. Belousov
- Department of Genetics and Biotechnology St. Petersburg State University 199034 St. Petersburg Russia
- Laboratory for Proteomics of Supra-Organismal Systems All-Russia Research Institute for Agricultural Microbiology (ARRIAM) 196608 St. Petersburg Russia
| | - Vladislav A. Salikov
- Laboratory of Biomolecular NMR St. Petersburg State University 199034 St. Petersburg Russia
| | - Galina A. Zhouravleva
- Department of Genetics and Biotechnology St. Petersburg State University 199034 St. Petersburg Russia
| | - Nikolai R. Skrynnikov
- Laboratory of Biomolecular NMR St. Petersburg State University 199034 St. Petersburg Russia
- Department of Chemistry Purdue University West Lafayette IN 47907 USA
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12
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Protofibril–Fibril Interactions Inhibit Amyloid Fibril Assembly by Obstructing Secondary Nucleation. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202010098] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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13
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Hasecke F, Niyangoda C, Borjas G, Pan J, Matthews G, Muschol M, Hoyer W. Protofibril-Fibril Interactions Inhibit Amyloid Fibril Assembly by Obstructing Secondary Nucleation. Angew Chem Int Ed Engl 2021; 60:3016-3021. [PMID: 33095508 PMCID: PMC7898819 DOI: 10.1002/anie.202010098] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Revised: 10/16/2020] [Indexed: 12/29/2022]
Abstract
Amyloid-β peptides (Aβ) assemble into both rigid amyloid fibrils and metastable oligomers termed AβO or protofibrils. In Alzheimer's disease, Aβ fibrils constitute the core of senile plaques, but Aβ protofibrils may represent the main toxic species. Aβ protofibrils accumulate at the exterior of senile plaques, yet the protofibril-fibril interplay is not well understood. Applying chemical kinetics and atomic force microscopy to the assembly of Aβ and lysozyme, protofibrils are observed to bind to the lateral surfaces of amyloid fibrils. When utilizing Aβ variants with different critical oligomer concentrations, the interaction inhibits the autocatalytic proliferation of amyloid fibrils by secondary nucleation on the fibril surface. Thus, metastable oligomers antagonize their replacement by amyloid fibrils both by competing for monomers and blocking secondary nucleation sites. The protofibril-fibril interaction governs their temporal evolution and potential to exert specific toxic activities.
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Affiliation(s)
- Filip Hasecke
- Institut für Physikalische BiologieHeinrich-Heine-Universität Düsseldorf40204DüsseldorfGermany
| | | | - Gustavo Borjas
- Department of PhysicsUniversity of South FloridaTampaFL33620USA
| | - Jianjun Pan
- Department of PhysicsUniversity of South FloridaTampaFL33620USA
| | | | - Martin Muschol
- Department of PhysicsUniversity of South FloridaTampaFL33620USA
| | - Wolfgang Hoyer
- Institut für Physikalische BiologieHeinrich-Heine-Universität Düsseldorf40204DüsseldorfGermany
- Strukturbiochemie (IBI-7)Forschungszentrum Jülich52425JülichGermany
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14
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Strodel B. Amyloid aggregation simulations: challenges, advances and perspectives. Curr Opin Struct Biol 2020; 67:145-152. [PMID: 33279865 DOI: 10.1016/j.sbi.2020.10.019] [Citation(s) in RCA: 54] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2020] [Accepted: 10/18/2020] [Indexed: 10/22/2022]
Abstract
In amyloid aggregation diseases soluble proteins coalesce into a wide array of undesirable structures, ranging through oligomers and prefibrillar assemblies to highly ordered amyloid fibrils and plaques. Explicit-solvent all-atom molecular dynamics (MD) simulations of amyloid aggregation have been performed for almost 20 years, revealing valuable information about this phenomenon. However, these simulations are challenged by three main problems. Firstly, current force fields modeling amyloid aggregation are insufficiently accurate. Secondly, the protein concentrations in MD simulations are usually orders of magnitude higher than those used in vitro or found in vivo, which has direct consequences on the aggregates that form. Finally, the third problem is the well-known time-scale limit of MD simulations. In this review I highlight recent approaches to overcome these three limitations.
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Affiliation(s)
- Birgit Strodel
- Institute of Biological Information Processing (IBI-7: Structural Biochemistry), Forschungszentrum Jülich, 52425 Jülich, Germany; Institute of Theoretical and Computational Chemistry, Heinrich Heine University Düsseldorf, Universitätstrasse 1, 40225 Düsseldorf, Germany.
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15
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You X, Wang X, Zhang HJ, Cui K, Zhang A, Wang L, Yadav C, Li X. Supertough Lignin Hydrogels with Multienergy Dissipative Structures and Ultrahigh Antioxidative Activities. ACS APPLIED MATERIALS & INTERFACES 2020; 12:39892-39901. [PMID: 32805809 DOI: 10.1021/acsami.0c10657] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Hydrogels derived from lignin are typically weak and contain only a small amount of lignin, which limits their broad application prospects. In the present work, a novel lignin/poly(N,N-dimethylacrylamide) (PDMA) hydrogel with a high lignin content, superb toughness, and ultrahigh antioxidative performance is constructed by employing a facile dissolve-dry-swell solvent exchange method. Through this process, lignin and PDMA are self-assembled into a multienergy dissipative structure containing rigid lignin-rich domains. Precisely, the PDMA chains both interpenetrated inside and adhered on the surface of these domains through hydrophobic associations. This structure enables the lignin hydrogels to dissipate energy efficiently during the fracture process. At an optimized ultrahigh lignin content of 58% (dry weight basis), the prepared lignin hydrogel exhibited remarkable mechanical properties, such as a high elastic modulus (2.5 MPa), tensile strength (2.5 MPa), and super tensile strain (11.3), and an extremely high fracture energy above 16 000 J m-2. In addition, the tough lignin hydrogel exhibited a commendable antioxidant property and nontoxicity. All these advantageous properties provide the lignin/PDMA hydrogels with the potential for use in biomedical materials applications.
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Affiliation(s)
- Xiangyu You
- College of Bioresources Chemical and Materials Engineering, Shaanxi University of Science & Technology, Xi'an, Shaanxi 710021, China
| | - Xuelian Wang
- College of Bioresources Chemical and Materials Engineering, Shaanxi University of Science & Technology, Xi'an, Shaanxi 710021, China
| | - Hui Jie Zhang
- College of Bioresources Chemical and Materials Engineering, Shaanxi University of Science & Technology, Xi'an, Shaanxi 710021, China
| | - Kunpeng Cui
- Institute for Chemical Reaction Design and Discovery (WPI-ICReDD), Hokkaido University, Sapporo 001-0021, Japan
| | - Aokai Zhang
- Changzhou Institute of Industry Technology, Changzhou, Jiangsu 213164, China
| | - Linping Wang
- Graduate School of Agriculture, Hokkaido University, Sapporo 060-8589, Japan
| | - Chandravati Yadav
- College of Bioresources Chemical and Materials Engineering, Shaanxi University of Science & Technology, Xi'an, Shaanxi 710021, China
| | - Xinping Li
- College of Bioresources Chemical and Materials Engineering, Shaanxi University of Science & Technology, Xi'an, Shaanxi 710021, China
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16
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Barton J, Arias DS, Niyangoda C, Borjas G, Le N, Mohamed S, Muschol M. Kinetic Transition in Amyloid Assembly as a Screening Assay for Oligomer-Selective Dyes. Biomolecules 2019; 9:biom9100539. [PMID: 31569739 PMCID: PMC6843685 DOI: 10.3390/biom9100539] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2019] [Revised: 09/24/2019] [Accepted: 09/25/2019] [Indexed: 02/06/2023] Open
Abstract
Assembly of amyloid fibrils and small globular oligomers is associated with a significant number of human disorders that include Alzheimer’s disease, senile systemic amyloidosis, and type II diabetes. Recent findings implicate small amyloid oligomers as the dominant aggregate species mediating the toxic effects in these disorders. However, validation of this hypothesis has been hampered by the dearth of experimental techniques to detect, quantify, and discriminate oligomeric intermediates from late-stage fibrils, in vitro and in vivo. We have shown that the onset of significant oligomer formation is associated with a transition in thioflavin T kinetics from sigmoidal to biphasic kinetics. Here we showed that this transition can be exploited for screening fluorophores for preferential responses to oligomer over fibril formation. This assay identified crystal violet as a strongly selective oligomer-indicator dye for lysozyme. Simultaneous recordings of amyloid kinetics with thioflavin T and crystal violet enabled us to separate the combined signals into their underlying oligomeric and fibrillar components. We provided further evidence that this screening assay could be extended to amyloid-β peptides under physiological conditions. Identification of oligomer-selective dyes not only holds the promise of biomedical applications but provides new approaches for unraveling the mechanisms underlying oligomer versus fibril formation in amyloid assembly.
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Affiliation(s)
- Jeremy Barton
- Department of Physics, University of South Florida, Tampa, FL 33620, USA.
| | - D Sebastian Arias
- Department of Physics, University of South Florida, Tampa, FL 33620, USA.
| | - Chamani Niyangoda
- Department of Physics, University of South Florida, Tampa, FL 33620, USA.
| | - Gustavo Borjas
- Department of Physics, University of South Florida, Tampa, FL 33620, USA.
| | - Nathan Le
- Department of Physics, University of South Florida, Tampa, FL 33620, USA.
| | - Saefallah Mohamed
- Department of Physics, University of South Florida, Tampa, FL 33620, USA.
| | - Martin Muschol
- Department of Physics, University of South Florida, Tampa, FL 33620, USA.
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17
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Zhang T, Loschwitz J, Strodel B, Nagel-Steger L, Willbold D. Interference with Amyloid-β Nucleation by Transient Ligand Interaction. Molecules 2019; 24:E2129. [PMID: 31195746 PMCID: PMC6600523 DOI: 10.3390/molecules24112129] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2019] [Revised: 06/02/2019] [Accepted: 06/04/2019] [Indexed: 12/20/2022] Open
Abstract
Amyloid-β peptide (Aβ) is an intrinsically disordered protein (IDP) associated with Alzheimer's disease. The structural flexibility and aggregation propensity of Aβ pose major challenges for elucidating the interaction between Aβ monomers and ligands. All-D-peptides consisting solely of D-enantiomeric amino acid residues are interesting drug candidates that combine high binding specificity with high metabolic stability. Here we characterized the interaction between the 12-residue all-D-peptide D3 and Aβ42 monomers, and how the interaction influences Aβ42 aggregation. We demonstrate for the first time that D3 binds to Aβ42 monomers with submicromolar affinities. These two highly unstructured molecules are able to form complexes with 1:1 and other stoichiometries. Further, D3 at substoichiometric concentrations effectively slows down the β-sheet formation and Aβ42 fibrillation by modulating the nucleation process. The study provides new insights into the molecular mechanism of how D3 affects Aβ assemblies and contributes to our knowledge on the interaction between two IDPs.
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Affiliation(s)
- Tao Zhang
- Institute of Complex Systems, Structural Biochemistry (ICS-6), Forschungszentrum Jülich, 52425 Jülich, Germany.
- Institut für Physikalische Biologie, Heinrich-Heine-Universität Düsseldorf, 40225 Düsseldorf, Germany.
| | - Jennifer Loschwitz
- Institute of Complex Systems, Structural Biochemistry (ICS-6), Forschungszentrum Jülich, 52425 Jülich, Germany.
- Institute of Theoretical and Computational Chemistry, Heinrich-Heine-Universität Düsseldorf, 40225 Düsseldorf, Germany.
| | - Birgit Strodel
- Institute of Complex Systems, Structural Biochemistry (ICS-6), Forschungszentrum Jülich, 52425 Jülich, Germany.
- Institute of Theoretical and Computational Chemistry, Heinrich-Heine-Universität Düsseldorf, 40225 Düsseldorf, Germany.
| | - Luitgard Nagel-Steger
- Institute of Complex Systems, Structural Biochemistry (ICS-6), Forschungszentrum Jülich, 52425 Jülich, Germany.
- Institut für Physikalische Biologie, Heinrich-Heine-Universität Düsseldorf, 40225 Düsseldorf, Germany.
| | - Dieter Willbold
- Institute of Complex Systems, Structural Biochemistry (ICS-6), Forschungszentrum Jülich, 52425 Jülich, Germany.
- Institut für Physikalische Biologie, Heinrich-Heine-Universität Düsseldorf, 40225 Düsseldorf, Germany.
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18
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Österlund N, Luo J, Wärmländer SK, Gräslund A. Membrane-mimetic systems for biophysical studies of the amyloid-β peptide. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2019; 1867:492-501. [DOI: 10.1016/j.bbapap.2018.11.005] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Revised: 10/18/2018] [Accepted: 11/17/2018] [Indexed: 10/27/2022]
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19
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Zheng Y, Xu L, Yang J, Peng X, Wang H, Yu N, Hua Y, Zhao J, He J, Hong T. The effects of fluorescent labels on Aβ42
aggregation detected by fluorescence correlation spectroscopy. Biopolymers 2018; 109:e23237. [DOI: 10.1002/bip.23237] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2018] [Revised: 09/02/2018] [Accepted: 09/13/2018] [Indexed: 01/23/2023]
Affiliation(s)
- Yanpeng Zheng
- School of Sciences; Beijing Jiaotong University; Beijing China
| | - Lingwan Xu
- School of Sciences; Beijing Jiaotong University; Beijing China
| | - Jingfa Yang
- Institute of Chemistry; Chinese Academy of Sciences; Beijing China
| | - Xianglei Peng
- School of Sciences; Beijing Jiaotong University; Beijing China
| | - He Wang
- School of Sciences; Beijing Jiaotong University; Beijing China
| | - Na Yu
- School of Sciences; Beijing Jiaotong University; Beijing China
- Shandong Xinchuang Biological Technology Co., Ltd.; Jinan China
| | - Ying Hua
- School of Sciences; Beijing Jiaotong University; Beijing China
| | - Jiang Zhao
- Institute of Chemistry; Chinese Academy of Sciences; Beijing China
| | - Jinsheng He
- School of Sciences; Beijing Jiaotong University; Beijing China
| | - Tao Hong
- School of Sciences; Beijing Jiaotong University; Beijing China
- Institute for Viral Disease Control and Prevention; Chinese Centre for Disease Control and Prevention; Beijing China
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20
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Helal M, Igel-Egalon A, Lakmeche A, Mazzocco P, Perrillat-Mercerot A, Pujo-Menjouet L, Rezaei H, Tine LM. Stability analysis of a steady state of a model describing Alzheimer's disease and interactions with prion proteins. J Math Biol 2018; 78:57-81. [PMID: 30099569 DOI: 10.1007/s00285-018-1267-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2017] [Revised: 04/09/2018] [Indexed: 01/20/2023]
Abstract
Alzheimer's disease (AD) is a neuro-degenerative disease affecting more than 46 million people worldwide in 2015. AD is in part caused by the accumulation of A[Formula: see text] peptides inside the brain. These can aggregate to form insoluble oligomers or fibrils. Oligomers have the capacity to interact with neurons via membrane receptors such as prion proteins ([Formula: see text]). This interaction leads [Formula: see text] to be misfolded in oligomeric prion proteins ([Formula: see text]), transmitting a death signal to neurons. In the present work, we aim to describe the dynamics of A[Formula: see text] assemblies and the accumulation of toxic oligomeric species in the brain, by bringing together the fibrillation pathway of A[Formula: see text] peptides in one hand, and in the other hand A[Formula: see text] oligomerization process and their interaction with cellular prions, which has been reported to be involved in a cell-death signal transduction. The model is based on Becker-Döring equations for the polymerization process, with delayed differential equations accounting for structural rearrangement of the different reactants. We analyse the well-posedness of the model and show existence, uniqueness and non-negativity of solutions. Moreover, we demonstrate that this model admits a non-trivial steady state, which is found to be globally stable thanks to a Lyapunov function. We finally present numerical simulations and discuss the impact of model parameters on the whole dynamics, which could constitute the main targets for pharmaceutical industry.
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Affiliation(s)
- Mohammed Helal
- Laboratory of Biomathematics, University Sidi Bel Abbes, Sidi Bel Abbès, Algeria
| | | | - Abdelkader Lakmeche
- Laboratory of Biomathematics, University Sidi Bel Abbes, Sidi Bel Abbès, Algeria
| | - Pauline Mazzocco
- CNRS UMR 5558, Laboratoire de Biométrie et Biologie Evolutive, Université Claude Bernard Lyon 1, Université de Lyon, 69100, Villeurbanne, France
| | - Angélique Perrillat-Mercerot
- Laboratoire de Mathématiques et Applications, UMR CNRS 7348, SP2MI Equipe DACTIM-MIS, Université de Poitiers, 86962, Chasseneuil Futuroscope Cedex, France
| | - Laurent Pujo-Menjouet
- CNRS UMR 5208 Institut Camille Jordan, Université Claude Bernard Lyon 1, Université de Lyon, 69622, Villeurbanne Cedex, France. .,Inria Team Dracula, Inria Grenoble Rhône-Alpes Center, 69100, Villeurbanne, France.
| | - Human Rezaei
- UR892 Virologie Immunologie Moléculaires, INRA, 78352, Jouy-en-Josas, France
| | - Léon M Tine
- CNRS UMR 5208 Institut Camille Jordan, Université Claude Bernard Lyon 1, Université de Lyon, 69622, Villeurbanne Cedex, France.,Inria Team Dracula, Inria Grenoble Rhône-Alpes Center, 69100, Villeurbanne, France
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21
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Hasecke F, Miti T, Perez C, Barton J, Schölzel D, Gremer L, Grüning CSR, Matthews G, Meisl G, Knowles TPJ, Willbold D, Neudecker P, Heise H, Ullah G, Hoyer W, Muschol M. Origin of metastable oligomers and their effects on amyloid fibril self-assembly. Chem Sci 2018; 9:5937-5948. [PMID: 30079208 PMCID: PMC6050532 DOI: 10.1039/c8sc01479e] [Citation(s) in RCA: 70] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2018] [Accepted: 06/12/2018] [Indexed: 01/05/2023] Open
Abstract
Assembly of rigid amyloid fibrils with their characteristic cross-β sheet structure is a molecular signature of numerous neurodegenerative and non-neuropathic disorders. Frequently large populations of small globular amyloid oligomers (gOs) and curvilinear fibrils (CFs) precede the formation of late-stage rigid fibrils (RFs), and have been implicated in amyloid toxicity. Yet our understanding of the origin of these metastable oligomers, their role as on-pathway precursors or off-pathway competitors, and their effects on the self-assembly of amyloid fibrils remains incomplete. Using two unrelated amyloid proteins, amyloid-β and lysozyme, we find that gO/CF formation, analogous to micelle formation by surfactants, is delineated by a "critical oligomer concentration" (COC). Below this COC, fibril assembly replicates the sigmoidal kinetics of nucleated polymerization. Upon crossing the COC, assembly kinetics becomes biphasic with gO/CF formation responsible for the lag-free initial phase, followed by a second upswing dominated by RF nucleation and growth. RF lag periods below the COC, as expected, decrease as a power law in monomer concentration. Surprisingly, the build-up of gO/CFs above the COC causes a progressive increase in RF lag periods. Our results suggest that metastable gO/CFs are off-pathway from RF formation, confined by a condition-dependent COC that is distinct from RF solubility, underlie a transition from sigmoidal to biphasic assembly kinetics and, most importantly, not only compete with RFs for the shared monomeric growth substrate but actively inhibit their nucleation and growth.
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Affiliation(s)
- Filip Hasecke
- Institut für Physikalische Biologie , Heinrich-Heine-Universität , 40204 Düsseldorf , Germany .
| | - Tatiana Miti
- Department of Physics , University of South Florida , Tampa , FL 33620 , USA .
| | - Carlos Perez
- Department of Physics , University of South Florida , Tampa , FL 33620 , USA .
| | - Jeremy Barton
- Department of Physics , University of South Florida , Tampa , FL 33620 , USA .
| | - Daniel Schölzel
- Institut für Physikalische Biologie , Heinrich-Heine-Universität , 40204 Düsseldorf , Germany .
- Institute of Complex Systems (ICS-6) , Structural Biochemistry , Research Centre Jülich , Germany
| | - Lothar Gremer
- Institut für Physikalische Biologie , Heinrich-Heine-Universität , 40204 Düsseldorf , Germany .
- Institute of Complex Systems (ICS-6) , Structural Biochemistry , Research Centre Jülich , Germany
| | - Clara S R Grüning
- Institut für Physikalische Biologie , Heinrich-Heine-Universität , 40204 Düsseldorf , Germany .
| | - Garrett Matthews
- Department of Physics , University of South Florida , Tampa , FL 33620 , USA .
| | - Georg Meisl
- Department of Chemistry , University of Cambridge , Lensfield Road , Cambridge CB2 1EW , UK
| | - Tuomas P J Knowles
- Department of Chemistry , University of Cambridge , Lensfield Road , Cambridge CB2 1EW , UK
| | - Dieter Willbold
- Institut für Physikalische Biologie , Heinrich-Heine-Universität , 40204 Düsseldorf , Germany .
- Institute of Complex Systems (ICS-6) , Structural Biochemistry , Research Centre Jülich , Germany
| | - Philipp Neudecker
- Institut für Physikalische Biologie , Heinrich-Heine-Universität , 40204 Düsseldorf , Germany .
- Institute of Complex Systems (ICS-6) , Structural Biochemistry , Research Centre Jülich , Germany
| | - Henrike Heise
- Institut für Physikalische Biologie , Heinrich-Heine-Universität , 40204 Düsseldorf , Germany .
- Institute of Complex Systems (ICS-6) , Structural Biochemistry , Research Centre Jülich , Germany
| | - Ghanim Ullah
- Department of Physics , University of South Florida , Tampa , FL 33620 , USA .
| | - Wolfgang Hoyer
- Institut für Physikalische Biologie , Heinrich-Heine-Universität , 40204 Düsseldorf , Germany .
- Institute of Complex Systems (ICS-6) , Structural Biochemistry , Research Centre Jülich , Germany
| | - Martin Muschol
- Department of Physics , University of South Florida , Tampa , FL 33620 , USA .
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