1
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Behera DP, Subadini S, Freudenberg U, Sahoo H. Sulfation of hyaluronic acid reconfigures the mechanistic pathway of bone morphogenetic protein-2 aggregation. Int J Biol Macromol 2024; 263:130128. [PMID: 38350587 DOI: 10.1016/j.ijbiomac.2024.130128] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2023] [Revised: 02/03/2024] [Accepted: 02/09/2024] [Indexed: 02/15/2024]
Abstract
Bone morphogenetic protein-2 (BMP-2) is a critical growth factor of bone extracellular matrix (ECM), pivotal for osteogenesis. Glycosaminoglycans (GAGs), another vital ECM biomolecules, interact with growth factors, affecting signal transduction. Our study primarily focused on hyaluronic acid (HA), a prevalent GAG, and its sulfated derivative (SHA). We explored their impact on BMP-2's conformation, aggregation, and mechanistic pathways of aggregation using diverse optical and rheological methods. In the presence of HA and SHA, the secondary structure of BMP-2 underwent a structured transformation, characterized by a substantial increase in beta sheet content, and a detrimental alteration, manifesting as a shift towards unstructured content, respectively. Although both HA and SHA induced BMP-2 aggregation, their mechanisms differed. SHA led to rapid amorphous aggregates, while HA promoted amyloid fibrils with a lag phase and sigmoidal kinetics. Aggregate size and shape varied; HA produced larger structures, SHA smaller. Each aggregation type followed distinct pathways influenced by viscosity and excluded volume. Higher viscosity, low diffusivity of protein and higher excluded volume In the presence of HA promotes fibrillation having size in micrometer range. Low viscosity, high diffusivity of protein and lesser excluded volume leads to amorphous aggregate of size in nanometer range.
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Affiliation(s)
- Devi Prasanna Behera
- Biophysical and Protein Chemistry Lab, Department of Chemistry, National Institute of Technology, Rourkela 769008, Odisha, India
| | - Suchismita Subadini
- Biophysical and Protein Chemistry Lab, Department of Chemistry, National Institute of Technology, Rourkela 769008, Odisha, India
| | - Uwe Freudenberg
- Institute of Polymer Research, Technical University Dresden, 01307 Dresden, Germany
| | - Harekrushna Sahoo
- Biophysical and Protein Chemistry Lab, Department of Chemistry, National Institute of Technology, Rourkela 769008, Odisha, India; Center for Nanomaterials, National Institute of Technology, Rourkela 769008, Odisha, India.
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2
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Gutierrez-Merino C. Brain Hydrophobic Peptides Antagonists of Neurotoxic Amyloid β Peptide Monomers/Oligomers-Protein Interactions. Int J Mol Sci 2023; 24:13846. [PMID: 37762148 PMCID: PMC10531495 DOI: 10.3390/ijms241813846] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2023] [Revised: 09/02/2023] [Accepted: 09/05/2023] [Indexed: 09/29/2023] Open
Abstract
Amyloid β (Aβ) oligomers have been linked to Alzheimer's disease (AD) pathogenesis and are the main neurotoxic forms of Aβ. This review focuses on the following: (i) the Aβ(1-42):calmodulin interface as a model for the design of antagonist Aβ peptides and its limitations; (ii) proteolytic degradation as the major source of highly hydrophobic peptides in brain cells; and (iii) brain peptides that have been experimentally demonstrated to bind to Aβ monomers or oligomers, Aβ fibrils, or Aβ plaques. It is highlighted that the hydrophobic amino acid residues of the COOH-terminal segment of Aβ(1-42) play a key role in its interaction with intracellular protein partners linked to its neurotoxicity. The major source of highly hydrophobic endogenous peptides of 8-10 amino acids in neurons is the proteasome activity. Many canonical antigen peptides bound to the major histocompatibility complex class 1 are of this type. These highly hydrophobic peptides bind to Aβ and are likely to be efficient antagonists of the binding of Aβ monomers/oligomers concentrations in the nanomolar range with intracellular proteins. Also, their complexation with Aβ will protect them against endopeptidases, suggesting a putative chaperon-like physiological function for Aβ that has been overlooked until now. Remarkably, the hydrophobic amino acid residues of Aβ responsible for the binding of several neuropeptides partially overlap with those playing a key role in its interaction with intracellular protein partners that mediates its neurotoxicity. Therefore, these latter neuropeptides are also potential candidates to antagonize Aβ peptides binding to target proteins. In conclusion, the analysis performed in this review points out that hydrophobic endogenous brain neuropeptides could be valuable biomarkers to evaluate the risk of the onset of sporadic AD, as well as for the prognosis of AD.
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Affiliation(s)
- Carlos Gutierrez-Merino
- Instituto de Biomarcadores de Patologías Moleculares, Universidad de Extremadura, 06006 Badajoz, Spain
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3
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Weiffert T, Meisl G, Curk S, Cukalevski R, Šarić A, Knowles TPJ, Linse S. Influence of denaturants on amyloid β42 aggregation kinetics. Front Neurosci 2022; 16:943355. [PMID: 36203800 PMCID: PMC9531139 DOI: 10.3389/fnins.2022.943355] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2022] [Accepted: 08/08/2022] [Indexed: 11/24/2022] Open
Abstract
Amyloid formation is linked to devastating neurodegenerative diseases, motivating detailed studies of the mechanisms of amyloid formation. For Aβ, the peptide associated with Alzheimer’s disease, the mechanism and rate of aggregation have been established for a range of variants and conditions in vitro and in bodily fluids. A key outstanding question is how the relative stabilities of monomers, fibrils and intermediates affect each step in the fibril formation process. By monitoring the kinetics of aggregation of Aβ42, in the presence of urea or guanidinium hydrochloride (GuHCl), we here determine the rates of the underlying microscopic steps and establish the importance of changes in relative stability induced by the presence of denaturant for each individual step. Denaturants shift the equilibrium towards the unfolded state of each species. We find that a non-ionic denaturant, urea, reduces the overall aggregation rate, and that the effect on nucleation is stronger than the effect on elongation. Urea reduces the rate of secondary nucleation by decreasing the coverage of fibril surfaces and the rate of nucleus formation. It also reduces the rate of primary nucleation, increasing its reaction order. The ionic denaturant, GuHCl, accelerates the aggregation at low denaturant concentrations and decelerates the aggregation at high denaturant concentrations. Below approximately 0.25 M GuHCl, the screening of repulsive electrostatic interactions between peptides by the charged denaturant dominates, leading to an increased aggregation rate. At higher GuHCl concentrations, the electrostatic repulsion is completely screened, and the denaturing effect dominates. The results illustrate how the differential effects of denaturants on stability of monomer, oligomer and fibril translate to differential effects on microscopic steps, with the rate of nucleation being most strongly reduced.
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Affiliation(s)
- Tanja Weiffert
- Department of Biochemistry and Structural Biology, Lund University, Lund, Sweden
| | - Georg Meisl
- Yusuf Hamied Department of Chemistry, Centre for Misfolding Diseases, University of Cambridge, Cambridge, United Kingdom
- Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge, United Kingdom
| | - Samo Curk
- Department of Physics and Astronomy, University College London, London, United Kingdom
| | - Risto Cukalevski
- Department of Biochemistry and Structural Biology, Lund University, Lund, Sweden
| | - Anđela Šarić
- Department of Physics and Astronomy, University College London, London, United Kingdom
| | - Tuomas P. J. Knowles
- Yusuf Hamied Department of Chemistry, Centre for Misfolding Diseases, University of Cambridge, Cambridge, United Kingdom
- Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge, United Kingdom
- Cavendish Laboratory, Department of Physics, University of Cambridge, Cambridge, United Kingdom
| | - Sara Linse
- Department of Biochemistry and Structural Biology, Lund University, Lund, Sweden
- *Correspondence: Sara Linse,
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4
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Liang R, Tian Y, Viles JH. Cross-seeding of WT amyloid-β with Arctic but not Italian familial mutants accelerates fibril formation in Alzheimer's disease. J Biol Chem 2022; 298:102071. [PMID: 35643314 PMCID: PMC9243174 DOI: 10.1016/j.jbc.2022.102071] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Revised: 05/18/2022] [Accepted: 05/19/2022] [Indexed: 01/21/2023] Open
Abstract
Alzheimer’s disease (AD) involves the neurotoxic self-assembly of a 40 and 42 residue peptide, Amyloid-β (Aβ). Inherited early-onset AD can be caused by single point mutations within the Aβ sequence, including Arctic (E22G) and Italian (E22K) familial mutants. These mutations are heterozygous, resulting in an equal proportion of the WT and mutant Aβ isoform expression. It is therefore important to understand how these mixtures of Aβ isoforms interact with each other and influence the kinetics and morphology of their assembly into oligomers and fibrils. Using small amounts of nucleating fibril seeds, here, we systematically monitored the kinetics of fibril formation, comparing self-seeding with cross-seeding behavior of a range of isoform mixtures of Aβ42 and Aβ40. We confirm that Aβ40(WT) does not readily cross-seed Aβ42(WT) fibril formation. In contrast, fibril formation of Aβ40(Arctic) is hugely accelerated by Aβ42(WT) fibrils, causing an eight-fold reduction in the lag-time to fibrillization. We propose that cross-seeding between the more abundant Aβ40(Arctic) and Aβ42(WT) may be important for driving early-onset AD and will propagate fibril morphology as indicated by fibril twist periodicity. This kinetic behavior is not emulated by the Italian mutant, where minimal cross-seeding is observed. In addition, we studied the cross-seeding behavior of a C-terminal-amidated Aβ42 analog to probe the coulombic charge interplay between Glu22/Asp23/Lys28 and the C-terminal carboxylate. Overall, these studies highlight the role of cross-seeding between WT and mutant Aβ40/42 isoforms, which can impact the rate and structure of fibril assembly.
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Affiliation(s)
- Ruina Liang
- School of Biological and Behavioural Sciences, Queen Mary, University of London, London, United Kingdom
| | - Yao Tian
- School of Biological and Behavioural Sciences, Queen Mary, University of London, London, United Kingdom
| | - John H Viles
- School of Biological and Behavioural Sciences, Queen Mary, University of London, London, United Kingdom.
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5
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Rai M, Curley M, Coleman Z, Demontis F. Contribution of proteases to the hallmarks of aging and to age-related neurodegeneration. Aging Cell 2022; 21:e13603. [PMID: 35349763 PMCID: PMC9124314 DOI: 10.1111/acel.13603] [Citation(s) in RCA: 4] [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: 01/06/2022] [Revised: 03/10/2022] [Accepted: 03/13/2022] [Indexed: 12/20/2022] Open
Abstract
Protein quality control ensures the degradation of damaged and misfolded proteins. Derangement of proteostasis is a primary cause of aging and age-associated diseases. The ubiquitin-proteasome and autophagy-lysosome play key roles in proteostasis but, in addition to these systems, the human genome encodes for ~600 proteases, also known as peptidases. Here, we examine the role of proteases in aging and age-related neurodegeneration. Proteases are present across cell compartments, including the extracellular space, and their substrates encompass cellular constituents, proteins with signaling functions, and misfolded proteins. Proteolytic processing by proteases can lead to changes in the activity and localization of substrates or to their degradation. Proteases cooperate with the autophagy-lysosome and ubiquitin-proteasome systems but also have independent proteolytic roles that impact all hallmarks of cellular aging. Specifically, proteases regulate mitochondrial function, DNA damage repair, cellular senescence, nutrient sensing, stem cell properties and regeneration, protein quality control and stress responses, and intercellular signaling. The capacity of proteases to regulate cellular functions translates into important roles in preserving tissue homeostasis during aging. Consequently, proteases influence the onset and progression of age-related pathologies and are important determinants of health span. Specifically, we examine how certain proteases promote the progression of Alzheimer's, Huntington's, and/or Parkinson's disease whereas other proteases protect from neurodegeneration. Mechanistically, cleavage by proteases can lead to the degradation of a pathogenic protein and hence impede disease pathogenesis. Alternatively, proteases can generate substrate byproducts with increased toxicity, which promote disease progression. Altogether, these studies indicate the importance of proteases in aging and age-related neurodegeneration.
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Affiliation(s)
- Mamta Rai
- Department of Developmental NeurobiologySt. Jude Children’s Research HospitalMemphisTennesseeUSA
| | - Michelle Curley
- Department of Developmental NeurobiologySt. Jude Children’s Research HospitalMemphisTennesseeUSA
| | - Zane Coleman
- Department of Developmental NeurobiologySt. Jude Children’s Research HospitalMemphisTennesseeUSA
| | - Fabio Demontis
- Department of Developmental NeurobiologySt. Jude Children’s Research HospitalMemphisTennesseeUSA
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6
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Howitz WJ, Guaglianone G, McKnelly KJ, Haduong K, Ashby SN, Laayouni M, Nowick JS. Macrocyclic Peptides Derived from Familial Alzheimer's Disease Mutants Show Charge-Dependent Oligomeric Assembly and Toxicity. ACS Chem Neurosci 2022; 13:714-720. [PMID: 35191689 PMCID: PMC9042422 DOI: 10.1021/acschemneuro.1c00833] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
This work probes the role of charge in the oligomeric assembly, toxicity, and membrane destabilization of a series of peptides derived from Aβ and the E22Q and E22K familial mutants. In the mutant Aβ peptides, an acidic residue (E) is replaced with either a neutral or basic residue (Q or K), thus altering the net charge of the peptide. Acetylation at peripheral positions permits modulation of charge of the peptides and allows investigation of the role of charge in their oligomeric assembly, cytotoxicity, and membrane disruption. Peptides with the same net charge generally behave similarly even if the amino acid residue at position 22 differs. As the net charge of the peptide decreases, so does the extent of assembly, cytotoxicity, and membrane destabilization, which were determined using sodium dodecyl sulfate-polyacrylamide gel electrophoresis, lactate dehydrogenase (LDH)-release assays with SH-SY5Y cells, and dye leakage assays using liposomes. These findings suggest that the charge of the amino acid side chain, rather than its size or hydrophobicity, accounts for the differences in the oligomeric assembly and toxicity of the E22 familial mutants of Aβ.
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Affiliation(s)
- William J Howitz
- Department of Chemistry, University of California, Irvine, Irvine, California 92697, United States
| | - Gretchen Guaglianone
- Department of Chemistry, University of California, Irvine, Irvine, California 92697, United States
| | - Kate J McKnelly
- Department of Chemistry, University of California, Irvine, Irvine, California 92697, United States
| | - Katelyn Haduong
- Department of Chemistry, University of California, Irvine, Irvine, California 92697, United States
| | - Shareen N Ashby
- Department of Chemistry, University of California, Irvine, Irvine, California 92697, United States
| | - Mohamed Laayouni
- Department of Chemistry, University of California, Irvine, Irvine, California 92697, United States
| | - James S Nowick
- Department of Chemistry, University of California, Irvine, Irvine, California 92697, United States.,Department of Pharmaceutical Sciences, University of California, Irvine, Irvine, California 92697, United States
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7
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Sandin L, Sjödin S, Brorsson AC, Kågedal K, Civitelli L. The Luminescent Conjugated Oligothiophene h-FTAA Attenuates the Toxicity of Different Aβ Species. Biochemistry 2021; 60:2773-2780. [PMID: 34469142 PMCID: PMC8459454 DOI: 10.1021/acs.biochem.1c00265] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The prevailing opinion is that prefibrillar β-amyloid (Aβ) species, rather than end-stage amyloid fibrils, cause neuronal dysfunction in Alzheimer's disease, although the mechanisms behind Aβ neurotoxicity remain to be elucidated. Luminescent conjugated oligothiophenes (LCOs) exhibit spectral properties upon binding to amyloid proteins and have previously been reported to change the toxicity of Aβ1-42 and prion protein. In a previous study, we showed that an LCO, pentamer formyl thiophene acetic acid (p-FTAA), changed the toxicity of Aβ1-42. Here we investigated whether an LCO, heptamer formyl thiophene acetic acid (h-FTAA), could change the toxicity of Aβ1-42 by comparing its behavior with that of p-FTAA. Moreover, we investigated the effects on toxicity when Aβ with the Arctic mutation (AβArc) was aggregated with both LCOs. Cell viability assays on SH-SY5Y neuroblastoma cells demonstrated that h-FTAA has a stronger impact on Aβ1-42 toxicity than does p-FTAA. Interestingly, h-FTAA, but not p-FTAA, rescued the AβArc-mediated toxicity. Aggregation kinetics and binding assay experiments with Aβ1-42 and AβArc when aggregated with both LCOs showed that h-FTAA and p-FTAA either interact with different species or affect the aggregation in different ways. In conclusion, h-FTAA protects against Aβ1-42 and AβArc toxicity, thus showing h-FTAA to be a useful tool for improving our understanding of the process of Aβ aggregation linked to cytotoxicity.
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Affiliation(s)
- Linnea Sandin
- Experimental Pathology, Department of Clinical and Experimental Medicine, Faculty of Health Sciences, Linköping University, Linköping 581 83, Sweden
| | - Simon Sjödin
- Experimental Pathology, Department of Clinical and Experimental Medicine, Faculty of Health Sciences, Linköping University, Linköping 581 83, Sweden
| | - Ann-Christin Brorsson
- Division of Molecular Biotechnology, Department of Physics, Chemistry and Biology, Linköping University, Linköping 581 83, Sweden
| | - Katarina Kågedal
- Experimental Pathology, Department of Clinical and Experimental Medicine, Faculty of Health Sciences, Linköping University, Linköping 581 83, Sweden
| | - Livia Civitelli
- Experimental Pathology, Department of Clinical and Experimental Medicine, Faculty of Health Sciences, Linköping University, Linköping 581 83, Sweden
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8
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Toward the equilibrium and kinetics of amyloid peptide self-assembly. Curr Opin Struct Biol 2021; 70:87-98. [PMID: 34153659 DOI: 10.1016/j.sbi.2021.05.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2021] [Revised: 05/09/2021] [Accepted: 05/09/2021] [Indexed: 01/28/2023]
Abstract
Several devastating human diseases are linked to peptide self-assembly, but our understanding their onset and progression is not settled. This is a sign of the complexity of the aggregation process, which is prevented, catalyzed, or retarded by numerous factors in body fluids and cells, varying in time and space. Biophysical studies of pure peptide solutions contribute insights into the underlying steps in the process and quantitative parameters relating to rate constants (energy barriers) and equilibrium constants (population distributions). This requires methods to quantify the concentration of at least one species in the process. Translation to an in vivo situation poses an enormous challenge, and the effects of selected components (bottom up) or entire body fluids (top down) need to be quantified.
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9
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Illes-Toth E, Meisl G, Rempel DL, Knowles TPJ, Gross ML. Pulsed Hydrogen-Deuterium Exchange Reveals Altered Structures and Mechanisms in the Aggregation of Familial Alzheimer's Disease Mutants. ACS Chem Neurosci 2021; 12:1972-1982. [PMID: 33988976 DOI: 10.1021/acschemneuro.1c00072] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Mutations of the Amyloid Precursor Protein, from which the amyloid β peptide Aβ42 is cleaved, are associated with familial Alzheimer's disease. The disease-relevant familial mutations include the Arctic (E22G), Iowa (D23N), Italian (E22K), Dutch (E22Q), Japanese (D7N), English (D6R), and Flemish (A21G) variants. A detailed mechanistic understanding of the aggregation behavior of the mutant peptides at the residue level is, however, still lacking. We report here a study of the aggregation kinetics of these mutants in vitro by pulsed hydrogen-deuterium exchange mass spectrometry (HDX-MS) to obtain a temporally and sequence resolved picture of their self-assembly. For all variants, HDX occurs to give a bimodal distribution representing two soluble classes of aggregates, one protected and one solvent-exposed. There is no evidence of other classes of structural intermediates within the detection limits of the HDX approach. The fractional changes in the bimodal exchange profiles for several regions of Aβ42 reveal that the central and C-terminal peptides gain protection upon fibril formation, whereas the N-terminal regions remain largely solvent-accessible. For these mutants, all peptide fragments follow the same kinetics, acquiring solvent protection at the same time, further supporting that there are no significant populations of intermediate species under our experimental conditions. The results demonstrate the potential of pulsed HDX-MS for resolving the region-specific aggregation behavior of Aβ42 isoforms in solution where X-ray crystallography and solid-state NMR (ssNMR) are challenged.
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Affiliation(s)
- Eva Illes-Toth
- Washington University in St. Louis, Department of Chemistry, St. Louis, Missouri 63130, United States
| | - Georg Meisl
- University of Cambridge, Department of Chemistry, Lensfield Road, Cambridge CB2 1EW, UK
| | - Don L. Rempel
- Washington University in St. Louis, Department of Chemistry, St. Louis, Missouri 63130, United States
| | - Tuomas P. J. Knowles
- University of Cambridge, Department of Chemistry, Lensfield Road, Cambridge CB2 1EW, UK
| | - Michael L. Gross
- Washington University in St. Louis, Department of Chemistry, St. Louis, Missouri 63130, United States
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10
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Anomalous Salt Dependence Reveals an Interplay of Attractive and Repulsive Electrostatic Interactions in α-synuclein Fibril Formation. QRB DISCOVERY 2020. [PMID: 37528959 PMCID: PMC10392692 DOI: 10.1017/qrd.2020.7] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Abstractα-Synuclein (α-syn) is an intrinsically disordered protein with a highly asymmetric charge distribution, whose aggregation is linked to Parkinson’s disease. The effect of ionic strength was investigated at mildly acidic pH (5.5) in the presence of catalytic surfaces in the form of α-syn seeds or anionic lipid vesicles using thioflavin T fluorescence measurements. Similar trends were observed with both surfaces: increasing ionic strength reduced the rate of α-syn aggregation although the surfaces as well as α-syn have a net negative charge at pH 5.5. This anomalous salt dependence implies that short-range attractive electrostatic interactions are critical for secondary nucleation as well as heterogeneous primary nucleation. Such interactions were confirmed in Monte Carlo simulations of α-syn monomers interacting with surface-grafted C-terminal tails, and found to be weakened in the presence of salt. Thus, nucleation of α-syn aggregation depends critically on an attractive electrostatic component that is screened by salt to the extent that it outweighs the screening of the long-range repulsion between negatively charged monomers and negative surfaces. Interactions between the positively charged N-termini of α-syn monomers on the one hand, and the negatively C-termini of α-syn on fibrils or vesicles surfaces on the other hand, are thus critical for nucleation.
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11
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Corbett GT, Wang Z, Hong W, Colom-Cadena M, Rose J, Liao M, Asfaw A, Hall TC, Ding L, DeSousa A, Frosch MP, Collinge J, Harris DA, Perkinton MS, Spires-Jones TL, Young-Pearse TL, Billinton A, Walsh DM. PrP is a central player in toxicity mediated by soluble aggregates of neurodegeneration-causing proteins. Acta Neuropathol 2020; 139:503-526. [PMID: 31853635 PMCID: PMC7035229 DOI: 10.1007/s00401-019-02114-9] [Citation(s) in RCA: 75] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2019] [Revised: 12/10/2019] [Accepted: 12/10/2019] [Indexed: 12/30/2022]
Abstract
Neurodegenerative diseases are an enormous public health problem, affecting tens of millions of people worldwide. Nearly all of these diseases are characterized by oligomerization and fibrillization of neuronal proteins, and there is great interest in therapeutic targeting of these aggregates. Here, we show that soluble aggregates of α-synuclein and tau bind to plate-immobilized PrP in vitro and on mouse cortical neurons, and that this binding requires at least one of the same N-terminal sites at which soluble Aβ aggregates bind. Moreover, soluble aggregates of tau, α-synuclein and Aβ cause both functional (impairment of LTP) and structural (neuritic dystrophy) compromise and these deficits are absent when PrP is ablated, knocked-down, or when neurons are pre-treated with anti-PrP blocking antibodies. Using an all-human experimental paradigm involving: (1) isogenic iPSC-derived neurons expressing or lacking PRNP, and (2) aqueous extracts from brains of individuals who died with Alzheimer's disease, dementia with Lewy bodies, and Pick's disease, we demonstrate that Aβ, α-synuclein and tau are toxic to neurons in a manner that requires PrPC. These results indicate that PrP is likely to play an important role in a variety of late-life neurodegenerative diseases and that therapeutic targeting of PrP, rather than individual disease proteins, may have more benefit for conditions which involve the aggregation of more than one protein.
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Affiliation(s)
- Grant T Corbett
- Laboratory for Neurodegenerative Research, Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital and Harvard Medical School, Hale Building for Transformative Medicine, 60 Fenwood Road, Boston, MA, 02115, USA
| | - Zemin Wang
- Laboratory for Neurodegenerative Research, Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital and Harvard Medical School, Hale Building for Transformative Medicine, 60 Fenwood Road, Boston, MA, 02115, USA
| | - Wei Hong
- Laboratory for Neurodegenerative Research, Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital and Harvard Medical School, Hale Building for Transformative Medicine, 60 Fenwood Road, Boston, MA, 02115, USA
| | - Marti Colom-Cadena
- Centre for Discovery Brain Sciences and UK Dementia Research Institute, University of Edinburgh, Edinburgh, EH89JZ, UK
| | - Jamie Rose
- Centre for Discovery Brain Sciences and UK Dementia Research Institute, University of Edinburgh, Edinburgh, EH89JZ, UK
| | - Meichen Liao
- Laboratory for Neurodegenerative Research, Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital and Harvard Medical School, Hale Building for Transformative Medicine, 60 Fenwood Road, Boston, MA, 02115, USA
| | - Adhana Asfaw
- Laboratory for Neurodegenerative Research, Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital and Harvard Medical School, Hale Building for Transformative Medicine, 60 Fenwood Road, Boston, MA, 02115, USA
| | - Tia C Hall
- Laboratory for Neurodegenerative Research, Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital and Harvard Medical School, Hale Building for Transformative Medicine, 60 Fenwood Road, Boston, MA, 02115, USA
| | - Lai Ding
- Program for Interdisciplinary Neuroscience, Brigham and Women's Hospital, Boston, MA, 02115, USA
| | - Alexandra DeSousa
- Laboratory for Neurodegenerative Research, Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital and Harvard Medical School, Hale Building for Transformative Medicine, 60 Fenwood Road, Boston, MA, 02115, USA
| | - Matthew P Frosch
- Massachusetts General Institute for Neurodegenerative Disease, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA, 02129, USA
| | - John Collinge
- MRC Prion Unit at UCL, UCL Institute of Prion Diseases, National Hospital for Neurology and Neurosurgery, Queen Square, London, WC1N 3BG, UK
| | - David A Harris
- Department of Biochemistry, Boston University School of Medicine, Boston, MA, 02118, USA
| | | | - Tara L Spires-Jones
- Centre for Discovery Brain Sciences and UK Dementia Research Institute, University of Edinburgh, Edinburgh, EH89JZ, UK
| | - Tracy L Young-Pearse
- Laboratory for Neurodegenerative Research, Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital and Harvard Medical School, Hale Building for Transformative Medicine, 60 Fenwood Road, Boston, MA, 02115, USA
| | - Andrew Billinton
- Neuroscience, IMED Biotechnology Unit, AstraZeneca, Cambridge, CB21 6GH, UK
| | - Dominic M Walsh
- Laboratory for Neurodegenerative Research, Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital and Harvard Medical School, Hale Building for Transformative Medicine, 60 Fenwood Road, Boston, MA, 02115, USA.
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12
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Wille H, Dorosh L, Amidian S, Schmitt-Ulms G, Stepanova M. Combining molecular dynamics simulations and experimental analyses in protein misfolding. ADVANCES IN PROTEIN CHEMISTRY AND STRUCTURAL BIOLOGY 2020; 118:33-110. [PMID: 31928730 DOI: 10.1016/bs.apcsb.2019.10.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The fold of a protein determines its function and its misfolding can result in loss-of-function defects. In addition, for certain proteins their misfolding can lead to gain-of-function toxicities resulting in protein misfolding diseases such as Alzheimer's, Parkinson's, or the prion diseases. In all of these diseases one or more proteins misfold and aggregate into disease-specific assemblies, often in the form of fibrillar amyloid deposits. Most, if not all, protein misfolding diseases share a fundamental molecular mechanism that governs the misfolding and subsequent aggregation. A wide variety of experimental methods have contributed to our knowledge about misfolded protein aggregates, some of which are briefly described in this review. The misfolding mechanism itself is difficult to investigate, as the necessary timescale and resolution of the misfolding events often lie outside of the observable parameter space. Molecular dynamics simulations fill this gap by virtue of their intrinsic, molecular perspective and the step-by-step iterative process that forms the basis of the simulations. This review focuses on molecular dynamics simulations and how they combine with experimental analyses to provide detailed insights into protein misfolding and the ensuing diseases.
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Affiliation(s)
- Holger Wille
- Department of Biochemistry, University of Alberta, Edmonton, Canada; Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Canada; Neuroscience and Mental Health Institute, University of Alberta, Edmonton, Canada
| | - Lyudmyla Dorosh
- Department of Electrical and Computer Engineering, University of Alberta, Edmonton, Canada
| | - Sara Amidian
- Department of Biochemistry, University of Alberta, Edmonton, Canada; Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Canada
| | - Gerold Schmitt-Ulms
- Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Canada
| | - Maria Stepanova
- Department of Electrical and Computer Engineering, University of Alberta, Edmonton, Canada
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13
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Sanagavarapu K, Nüske E, Nasir I, Meisl G, Immink JN, Sormanni P, Vendruscolo M, Knowles TPJ, Malmendal A, Cabaleiro-Lago C, Linse S. A method of predicting the in vitro fibril formation propensity of Aβ40 mutants based on their inclusion body levels in E. coli. Sci Rep 2019; 9:3680. [PMID: 30842594 PMCID: PMC6403284 DOI: 10.1038/s41598-019-39216-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2018] [Accepted: 12/12/2018] [Indexed: 12/12/2022] Open
Abstract
Overexpression of recombinant proteins in bacteria may lead to their aggregation and deposition in inclusion bodies. Since the conformational properties of proteins in inclusion bodies exhibit many of the characteristics typical of amyloid fibrils. Based on these findings, we hypothesize that the rate at which proteins form amyloid fibrils may be predicted from their propensity to form inclusion bodies. To establish a method based on this concept, we first measured by SDS-PAGE and confocal microscopy the level of inclusion bodies in E. coli cells overexpressing the 40-residue amyloid-beta peptide, Aβ40, wild-type and 24 charge mutants. We then compared these results with a number of existing computational aggregation propensity predictors as well as the rates of aggregation measured in vitro for selected mutants. Our results show a strong correlation between the level of inclusion body formation and aggregation propensity, thus demonstrating the power of this approach and its value in identifying factors modulating aggregation kinetics.
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Affiliation(s)
- Kalyani Sanagavarapu
- Lund University, Biochemistry and Structural Biology, Chemical Center, Lund, Sweden.
| | | | - Irem Nasir
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, 10550 N, Torrey Pines Road, La Jolla, CA, 92037, USA
| | - Georg Meisl
- University of Cambridge, Chemistry Department, Lensfield Road, Cambridge, UK
| | - Jasper N Immink
- Lund University, Physical Chemistry, Chemical Center, Lund, Sweden
| | - Pietro Sormanni
- University of Cambridge, Chemistry Department, Lensfield Road, Cambridge, UK
| | - Michele Vendruscolo
- University of Cambridge, Chemistry Department, Lensfield Road, Cambridge, UK
| | - Tuomas P J Knowles
- University of Cambridge, Chemistry Department, Lensfield Road, Cambridge, UK.,Cavendish Laboratory, Department of Physics, University of Cambridge, JJ Thomson Avenue, Cambridge, UK
| | - Anders Malmendal
- Lund University, Biochemistry and Structural Biology, Chemical Center, Lund, Sweden
| | - Celia Cabaleiro-Lago
- Lund University, Biochemistry and Structural Biology, Chemical Center, Lund, Sweden.,Faculty of natural sciences, Kristianstad University, Kristianstad, Sweden
| | - Sara Linse
- Lund University, Biochemistry and Structural Biology, Chemical Center, Lund, Sweden.
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14
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Martínez-Bonet M, Muñoz-Fernández MÁ, Álvarez S. HIV-1 increases extracellular amyloid-beta levels through neprilysin regulation in primary cultures of human astrocytes. J Cell Physiol 2018; 234:5880-5887. [PMID: 29323711 DOI: 10.1002/jcp.26462] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2017] [Accepted: 01/05/2018] [Indexed: 11/11/2022]
Abstract
Since the success of combined antiretroviral therapy, HIV-1-infected individuals are now living much longer. This increased life expectancy is accompanied by a higher prevalence of HIV-1 associated neurocognitive disorders. Rising too is the incidence in these patients of pathological hallmarks of Alzheimer's disease such as increased deposition of amyloid beta protein (Aβ). Although neurons are major sources of Aβ in the brain, astrocytes are the most numerous glial cells, therefore, even a small level of astrocytic Aβ metabolism could make a significant contribution to brain pathology. Neprilysin (NEP) is a decisive/crucial regulator of Aβ levels. We evaluated the effects of HIV-1 on Aβ deposition and the expression and activity of NEP in primary human astrocytes. Specifically, no differences in intracellular amyloid deposits were found between infected and control cells. However, primary cultures of infected astrocytes showed more extracellular Aβ levels compared to controls. This was accompanied by reduced expression of NEP and to a significant decrease in its activity. These results indicate that the presence of HIV-1 in the brain could contribute to the increase in the total burden of cerebral Aβ.
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Affiliation(s)
- Marta Martínez-Bonet
- Laboratorio Inmuno-Biología Molecular, Hospital General Universitario Gregorio Marañón, Madrid, Spain.,Instituto de Investigación Sanitaria Gregorio Marañón, Madrid, Spain.,Networking Research Center on Bioengineering, Biomaterials and Nanomedicine, Madrid, Spain
| | - M Ángeles Muñoz-Fernández
- Laboratorio Inmuno-Biología Molecular, Hospital General Universitario Gregorio Marañón, Madrid, Spain.,Instituto de Investigación Sanitaria Gregorio Marañón, Madrid, Spain.,Networking Research Center on Bioengineering, Biomaterials and Nanomedicine, Madrid, Spain
| | - Susana Álvarez
- Laboratorio Inmuno-Biología Molecular, Hospital General Universitario Gregorio Marañón, Madrid, Spain.,Instituto de Investigación Sanitaria Gregorio Marañón, Madrid, Spain
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15
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On the role of sidechain size and charge in the aggregation of A β42 with familial mutations. Proc Natl Acad Sci U S A 2018; 115:E5849-E5858. [PMID: 29895690 PMCID: PMC6042101 DOI: 10.1073/pnas.1803539115] [Citation(s) in RCA: 72] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
The aggregation of the amyloid-β (Aβ) peptide into amyloid fibrils is associated with Alzheimer’s disease, and several point mutations leading to early-onset disease have been identified in Aβ. By studying the aggregation of five disease-related mutations in vitro, we rationalize their link to familial Alzheimer’s disease. We have determined the effect of mutations on the individual steps of the overall Aβ42 aggregation reaction and find for four of the mutations a significant increase in the rate of self-replication of fibrils, a process that has been linked to the production of toxic oligomeric species. Furthermore, by investigating the nature of the mutation, we determine the importance of the charge and size of specific residues in the aggregation of the wild-type peptide. The aggregation of the amyloid-β (Aβ) peptide is linked to the pathogenesis of Alzheimer’s disease (AD). In particular, some point mutations within Aβ are associated with early-onset familial Alzheimer’s disease. Here we set out to explore how the physical properties of the altered side chains, including their sizes and charges, affect the molecular mechanisms of aggregation. We focus on Aβ42 with familial mutations—A21G (Flemish), E22K (Italian), E22G (Arctic), E22Q (Dutch), and D23N (Iowa)—which lead to similar or identical pathology with sporadic AD or severe cerebral amyloid angiopathy. Through global kinetic analysis, we find that for the E22K, E22G, E22Q, and D23N mutations, the acceleration of the overall aggregation originates primarily from the modulation of the nucleation processes, in particular secondary nucleation on the surface of existing fibrils, whereas the elongation process is not significantly affected. Remarkably, the D23 position appears to be responsible for most of the charge effects during nucleation, while the size of the side chain at the E22 position plays a more significant role than its charge. Thus, we have developed a kinetic approach to determine the nature and the magnitude of the contribution of specific residues to the rate of individual steps of the aggregation reaction, through targeted mutations and variations in ionic strength. This strategy can help rationalize the effect of some disease-related mutations as well as yield insights into the mechanism of aggregation and the transition states of the wild-type protein.
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16
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Coskuner-Weber O, Uversky VN. Insights into the Molecular Mechanisms of Alzheimer's and Parkinson's Diseases with Molecular Simulations: Understanding the Roles of Artificial and Pathological Missense Mutations in Intrinsically Disordered Proteins Related to Pathology. Int J Mol Sci 2018; 19:E336. [PMID: 29364151 PMCID: PMC5855558 DOI: 10.3390/ijms19020336] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2017] [Revised: 01/14/2018] [Accepted: 01/16/2018] [Indexed: 12/18/2022] Open
Abstract
Amyloid-β and α-synuclein are intrinsically disordered proteins (IDPs), which are at the center of Alzheimer's and Parkinson's disease pathologies, respectively. These IDPs are extremely flexible and do not adopt stable structures. Furthermore, both amyloid-β and α-synuclein can form toxic oligomers, amyloid fibrils and other type of aggregates in Alzheimer's and Parkinson's diseases. Experimentalists face challenges in investigating the structures and thermodynamic properties of these IDPs in their monomeric and oligomeric forms due to the rapid conformational changes, fast aggregation processes and strong solvent effects. Classical molecular dynamics simulations complement experiments and provide structural information at the atomic level with dynamics without facing the same experimental limitations. Artificial missense mutations are employed experimentally and computationally for providing insights into the structure-function relationships of amyloid-β and α-synuclein in relation to the pathologies of Alzheimer's and Parkinson's diseases. Furthermore, there are several natural genetic variations that play a role in the pathogenesis of familial cases of Alzheimer's and Parkinson's diseases, which are related to specific genetic defects inherited in dominant or recessive patterns. The present review summarizes the current understanding of monomeric and oligomeric forms of amyloid-β and α-synuclein, as well as the impacts of artificial and pathological missense mutations on the structural ensembles of these IDPs using molecular dynamics simulations. We also emphasize the recent investigations on residual secondary structure formation in dynamic conformational ensembles of amyloid-β and α-synuclein, such as β-structure linked to the oligomerization and fibrillation mechanisms related to the pathologies of Alzheimer's and Parkinson's diseases. This information represents an important foundation for the successful and efficient drug design studies.
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Affiliation(s)
- Orkid Coskuner-Weber
- Türkisch-Deutsche Universität, Theoretical and Computational Biophysics Group, Molecular Biotechnology, Sahinkaya Caddesi, No. 86, Beykoz, Istanbul 34820, Turkey.
| | - Vladimir N Uversky
- Department of Molecular Medicine and USF Health Byrd Alzheimer's Research Institute, Morsani College of Medicine, University of South Florida, Tampa, FL 33612, USA.
- Laboratory of New Methods in Biology, Institute for Biological Instrumentation, Russian Academy of Sciences, 142290 Pushchino, Moscow Region, Russia.
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17
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Hu Y, Kienlen-Campard P, Tang TC, Perrin F, Opsomer R, Decock M, Pan X, Octave JN, Constantinescu SN, Smith SO. β-Sheet Structure within the Extracellular Domain of C99 Regulates Amyloidogenic Processing. Sci Rep 2017; 7:17159. [PMID: 29215043 PMCID: PMC5719365 DOI: 10.1038/s41598-017-17144-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2017] [Accepted: 11/20/2017] [Indexed: 11/15/2022] Open
Abstract
Familial mutations in C99 can increase the total level of the soluble Aβ peptides produced by proteolysis, as well as the Aβ42/Aβ40 ratio, both of which are linked to the progression of Alzheimer’s disease. We show that the extracellular sequence of C99 forms β-sheet structure upon interaction with membrane bilayers. Mutations that disrupt this structure result in a significant increase in Aβ production and, in specific cases, result in an increase in the amount of Aβ42 relative to Aβ40. Fourier transform infrared and solid-state NMR spectroscopic studies reveal a central β-hairpin within the extracellular sequence comprising Y10-E11-V12 and L17-V18-F19 connected by a loop involving H13-H14-Q15. These results suggest how familial mutations in the extracellular sequence influence C99 processing and provide a structural basis for the development of small molecule modulators that would reduce Aβ production.
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Affiliation(s)
- Yi Hu
- Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, NY, 11794, USA
| | | | - Tzu-Chun Tang
- Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, NY, 11794, USA
| | - Florian Perrin
- Institute of Neuroscience, Université catholique de Louvain, Brussels, 1200, Belgium.,Ludwig Institute for Cancer Research and de Duve Institute, Université catholique de Louvain, Brussels, 1200, Belgium
| | - Rémi Opsomer
- Institute of Neuroscience, Université catholique de Louvain, Brussels, 1200, Belgium
| | - Marie Decock
- Institute of Neuroscience, Université catholique de Louvain, Brussels, 1200, Belgium
| | - Xiaoshu Pan
- Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, NY, 11794, USA
| | - Jean-Noel Octave
- Institute of Neuroscience, Université catholique de Louvain, Brussels, 1200, Belgium
| | - Stefan N Constantinescu
- Ludwig Institute for Cancer Research and de Duve Institute, Université catholique de Louvain, Brussels, 1200, Belgium.
| | - Steven O Smith
- Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, NY, 11794, USA.
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18
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Human Brain-Derived Aβ Oligomers Bind to Synapses and Disrupt Synaptic Activity in a Manner That Requires APP. J Neurosci 2017; 37:11947-11966. [PMID: 29101243 DOI: 10.1523/jneurosci.2009-17.2017] [Citation(s) in RCA: 94] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2017] [Revised: 09/19/2017] [Accepted: 09/29/2017] [Indexed: 12/20/2022] Open
Abstract
Compelling genetic evidence links the amyloid precursor protein (APP) to Alzheimer's disease (AD) and several theories have been advanced to explain the relationship. A leading hypothesis proposes that a small amphipathic fragment of APP, the amyloid β-protein (Aβ), self-associates to form soluble aggregates that impair synaptic and network activity. Here, we used the most disease-relevant form of Aβ, protein isolated from AD brain. Using this material, we show that the synaptotoxic effects of Aβ depend on expression of APP and that the Aβ-mediated impairment of synaptic plasticity is accompanied by presynaptic effects that disrupt the excitatory/inhibitory (E/I) balance. The net increase in the E/I ratio and inhibition of plasticity are associated with Aβ localizing to synapses and binding of soluble Aβ aggregates to synapses requires the expression of APP. Our findings indicate a role for APP in AD pathogenesis beyond the generation of Aβ and suggest modulation of APP expression as a therapy for AD.SIGNIFICANCE STATEMENT Here, we report on the plasticity-disrupting effects of amyloid β-protein (Aβ) isolated from Alzheimer's disease (AD) brain and the requirement of amyloid precursor protein (APP) for these effects. We show that Aβ-containing AD brain extracts block hippocampal LTP, augment glutamate release probability, and disrupt the excitatory/inhibitory balance. These effects are associated with Aβ localizing to synapses and genetic ablation of APP prevents both Aβ binding and Aβ-mediated synaptic dysfunctions. Our results emphasize the importance of APP in AD and should stimulate new studies to elucidate APP-related targets suitable for pharmacological manipulation.
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19
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20
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McKinnie SMK, Wang W, Fischer C, McDonald T, Kalin KR, Iturrioz X, Llorens-Cortes C, Oudit GY, Vederas JC. Synthetic Modification within the “RPRL” Region of Apelin Peptides: Impact on Cardiovascular Activity and Stability to Neprilysin and Plasma Degradation. J Med Chem 2017; 60:6408-6427. [DOI: 10.1021/acs.jmedchem.7b00723] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Shaun M. K. McKinnie
- Department of Chemistry, University of Alberta, 11227 Saskatchewan Drive NW, Edmonton, Alberta T6G 2G2, Canada
| | - Wang Wang
- Department of Medicine, University of Alberta, 8440-112 Street NW, Edmonton, Alberta T6G 2B7, Canada
- Mazankowski Alberta Heart Institute, University of Alberta, 8440-112 Street NW, Edmonton, Alberta T6G 2B7, Canada
| | - Conrad Fischer
- Department of Chemistry, University of Alberta, 11227 Saskatchewan Drive NW, Edmonton, Alberta T6G 2G2, Canada
| | - Tyler McDonald
- Department of Chemistry, University of Alberta, 11227 Saskatchewan Drive NW, Edmonton, Alberta T6G 2G2, Canada
| | - Kevin R. Kalin
- Department of Chemistry, University of Alberta, 11227 Saskatchewan Drive NW, Edmonton, Alberta T6G 2G2, Canada
| | - Xavier Iturrioz
- Laboratory of Central Neuropeptides in the Regulation of Body Fluid Homeostasis and Cardiovascular Functions, INSERM, U1050, Paris, F-75005, France
- Center for Interdisciplinary Research in Biology (CIRB), College de France, Paris, F-75005, France
- CNRS, UMR 7241, Paris, F-75005, France
| | - Catherine Llorens-Cortes
- Laboratory of Central Neuropeptides in the Regulation of Body Fluid Homeostasis and Cardiovascular Functions, INSERM, U1050, Paris, F-75005, France
- Center for Interdisciplinary Research in Biology (CIRB), College de France, Paris, F-75005, France
- CNRS, UMR 7241, Paris, F-75005, France
| | - Gavin Y. Oudit
- Department of Medicine, University of Alberta, 8440-112 Street NW, Edmonton, Alberta T6G 2B7, Canada
- Mazankowski Alberta Heart Institute, University of Alberta, 8440-112 Street NW, Edmonton, Alberta T6G 2B7, Canada
| | - John C. Vederas
- Department of Chemistry, University of Alberta, 11227 Saskatchewan Drive NW, Edmonton, Alberta T6G 2G2, Canada
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21
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Meisl G, Yang X, Dobson CM, Linse S, Knowles TPJ. Modulation of electrostatic interactions to reveal a reaction network unifying the aggregation behaviour of the Aβ42 peptide and its variants. Chem Sci 2017; 8:4352-4362. [PMID: 28979758 PMCID: PMC5580342 DOI: 10.1039/c7sc00215g] [Citation(s) in RCA: 58] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2017] [Accepted: 04/03/2017] [Indexed: 01/07/2023] Open
Abstract
The aggregation of the amyloid β peptide (Aβ42), which is linked to Alzheimer's disease, can be altered significantly by modulations of the peptide's intermolecular electrostatic interactions. Variations in sequence and solution conditions have been found to lead to highly variable aggregation behaviour. Here we modulate systematically the electrostatic interactions governing the aggregation kinetics by varying the ionic strength of the solution. We find that changes in the solution ionic strength induce a switch in the reaction pathway, altering the dominant mechanisms of aggregate multiplication. This strategy thereby allows us to continuously sample a large space of different reaction mechanisms and develop a minimal reaction network that unifies the experimental kinetics under a wide range of different conditions. More generally, this universal reaction network connects previously separate systems, such as charge mutants of the Aβ42 peptide, on a continuous mechanistic landscape, providing a unified picture of the aggregation mechanism of Aβ42.
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Affiliation(s)
- Georg Meisl
- Department of Chemistry , University of Cambridge , Lensfield Road , Cambridge CB2 1EW , UK . ;
| | - Xiaoting Yang
- Chemistry Department and Molecular Protein Science , Lund University , P. O. Box 124 , SE221 00 Lund , Sweden .
| | - Christopher M Dobson
- Department of Chemistry , University of Cambridge , Lensfield Road , Cambridge CB2 1EW , UK . ;
| | - Sara Linse
- Chemistry Department and Molecular Protein Science , Lund University , P. O. Box 124 , SE221 00 Lund , Sweden .
| | - Tuomas P J Knowles
- Department of Chemistry , University of Cambridge , Lensfield Road , Cambridge CB2 1EW , UK . ;
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22
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Hatami A, Monjazeb S, Milton S, Glabe CG. Familial Alzheimer's Disease Mutations within the Amyloid Precursor Protein Alter the Aggregation and Conformation of the Amyloid-β Peptide. J Biol Chem 2017; 292:3172-3185. [PMID: 28049728 DOI: 10.1074/jbc.m116.755264] [Citation(s) in RCA: 92] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2016] [Revised: 12/28/2016] [Indexed: 11/06/2022] Open
Abstract
Most cases of Alzheimer's disease (AD) are sporadic, but a small percentage of AD cases, called familial AD (FAD), are associated with mutations in presenilin 1, presenilin 2, or the amyloid precursor protein. Amyloid precursor protein mutations falling within the amyloid-β (Aβ) sequence lead to a wide range of disease phenotypes. There is increasing evidence that distinct amyloid structures distinguished by amyloid conformation-dependent monoclonal antibodies have similarly distinct roles in pathology. It is possible that this phenotypic diversity of FAD associated with mutations within the Aβ sequence is due to differences in the conformations adopted by mutant Aβ peptides, but the effects of FAD mutations on aggregation kinetics and conformational and morphological changes of the Aβ peptide are poorly defined. To gain more insight into this possibility, we therefore investigated the effects of 11 FAD mutations on the aggregation kinetics of Aβ, as well as its ability to form distinct conformations recognized by a panel of amyloid conformation-specific monoclonal antibodies. We found that most FAD mutations increased the rate of aggregation of Aβ. The FAD mutations also led to the adoption of alternative amyloid conformations distinguished by monoclonal antibodies and resulted in the formation of distinct aggregate morphologies as determined by transmission electron microscopy. In addition, several of the mutant peptides displayed a large reduction in thioflavin T fluorescence, despite forming abundant fibrils indicating that thioflavin T is a probe of conformational polymorphisms rather than a reliable indicator of fibrillization. Taken together, these results indicate that FAD mutations falling within the Aβ sequence lead to dramatic changes in aggregation kinetics and influence the ability of Aβ to form immunologically and morphologically distinct amyloid structures.
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Affiliation(s)
- Asa Hatami
- Department of Molecular Biology and Biochemistry, University of California at Irvine, Irvine, California 92697; Department of Neurology, David Geffen School of Medicine at UCLA, Los Angeles, California 90095
| | - Sanaz Monjazeb
- Department of Molecular Biology and Biochemistry, University of California at Irvine, Irvine, California 92697
| | - Saskia Milton
- Department of Molecular Biology and Biochemistry, University of California at Irvine, Irvine, California 92697
| | - Charles G Glabe
- Department of Molecular Biology and Biochemistry, University of California at Irvine, Irvine, California 92697; Biochemistry Department, Faculty of Science and Experimental Biochemistry Unit, King Fahd Medical Research Center, King Abdulaziz University, 23218 Jeddah, Saudi Arabia.
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23
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O'Malley TT, Witbold WM, Linse S, Walsh DM. The Aggregation Paths and Products of Aβ42 Dimers Are Distinct from Those of the Aβ42 Monomer. Biochemistry 2016; 55:6150-6161. [PMID: 27750419 DOI: 10.1021/acs.biochem.6b00453] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Extracts of Alzheimer's disease (AD) brain that contain what appear to be sodium dodecyl sulfate-stable amyloid β-protein (Aβ) dimers potently block LTP and impair memory consolidation. Brain-derived dimers can be physically separated the Aβ monomer, consist primarily of Aβ42, and resist denaturation by chaotropic agents. In nature, covalently cross-linked Aβ dimers could be generated in two ways: by the formation of a dityrosine (DiY) or an isopeptide ε-(γ-glutamyl)-lysine (Q-K) bond. We enzymatically cross-linked recombinant Aβ42 monomer to produce DiY and Q-K dimers and then used a range of biophysical methods to study their aggregation. Both Q-K and DiY dimers aggregate to form soluble assemblies distinct from the fibrillar aggregates formed by the Aβ monomer. The results suggest that the cross-links disfavor fibril formation from Aβ dimers, thereby enhancing the concentration of soluble aggregates akin to those in aqueous extracts of AD brain. Thus, it seems that Aβ dimers may play an important role in determining the formation of soluble rather than insoluble aggregates.
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Affiliation(s)
- Tiernan T O'Malley
- Laboratory for Neurodegenerative Research, Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital and Harvard Medical School , Boston, Massachusetts 02115, United States.,School of Biomolecular and Biomedical Science, University College Dublin , Dublin 4, Republic of Ireland
| | - William M Witbold
- Wyatt Technology Corporation , 18 Commerce Way, Woburn, Massachusetts 01801, United States
| | - Sara Linse
- Department of Biochemistry and Structural Biology, Lund University , PO Box 124, SE221 00 Lund, Sweden
| | - Dominic M Walsh
- Laboratory for Neurodegenerative Research, Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital and Harvard Medical School , Boston, Massachusetts 02115, United States
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24
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Elkins MR, Wang T, Nick M, Jo H, Lemmin T, Prusiner SB, DeGrado WF, Stöhr J, Hong M. Structural Polymorphism of Alzheimer's β-Amyloid Fibrils as Controlled by an E22 Switch: A Solid-State NMR Study. J Am Chem Soc 2016; 138:9840-52. [PMID: 27414264 PMCID: PMC5149419 DOI: 10.1021/jacs.6b03715] [Citation(s) in RCA: 66] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The amyloid-β (Aβ) peptide of Alzheimer's disease (AD) forms polymorphic fibrils on the micrometer and molecular scales. Various fibril growth conditions have been identified to cause polymorphism, but the intrinsic amino acid sequence basis for this polymorphism has been unclear. Several single-site mutations in the center of the Aβ sequence cause different disease phenotypes and fibrillization properties. The E22G (Arctic) mutant is found in familial AD and forms protofibrils more rapidly than wild-type Aβ. Here, we use solid-state NMR spectroscopy to investigate the structure, dynamics, hydration and morphology of Arctic E22G Aβ40 fibrils. (13)C, (15)N-labeled synthetic E22G Aβ40 peptides are studied and compared with wild-type and Osaka E22Δ Aβ40 fibrils. Under the same fibrillization conditions, Arctic Aβ40 exhibits a high degree of polymorphism, showing at least four sets of NMR chemical shifts for various residues, while the Osaka and wild-type Aβ40 fibrils show a single or a predominant set of chemical shifts. Thus, structural polymorphism is intrinsic to the Arctic E22G Aβ40 sequence. Chemical shifts and inter-residue contacts obtained from 2D correlation spectra indicate that one of the major Arctic conformers has surprisingly high structural similarity with wild-type Aβ42. (13)C-(1)H dipolar order parameters, (1)H rotating-frame spin-lattice relaxation times and water-to-protein spin diffusion experiments reveal substantial differences in the dynamics and hydration of Arctic, Osaka and wild-type Aβ40 fibrils. Together, these results strongly suggest that electrostatic interactions in the center of the Aβ peptide sequence play a crucial role in the three-dimensional fold of the fibrils, and by inference, fibril-induced neuronal toxicity and AD pathogenesis.
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Affiliation(s)
- Matthew R. Elkins
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge MA 02139
| | - Tuo Wang
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge MA 02139
| | - Mimi Nick
- Department of Pharmaceutical Chemistry, University of California, San Francisco, San Francisco, CA 94158
| | - Hyunil Jo
- Department of Pharmaceutical Chemistry, University of California, San Francisco, San Francisco, CA 94158
| | - Thomas Lemmin
- Department of Pharmaceutical Chemistry, University of California, San Francisco, San Francisco, CA 94158
| | - Stanley B. Prusiner
- Institute for Neurodegenerative Diseases, Departments of Neurology, University of California, San Francisco, San Francisco, CA 94143
| | - William F. DeGrado
- Department of Pharmaceutical Chemistry, University of California, San Francisco, San Francisco, CA 94158
| | - Jan Stöhr
- Institute for Neurodegenerative Diseases, Departments of Neurology, University of California, San Francisco, San Francisco, CA 94143
| | - Mei Hong
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge MA 02139
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25
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Langenickel TH, Tsubouchi C, Ayalasomayajula S, Pal P, Valentin M, Hinder M, Jhee S, Gevorkyan H, Rajman I. The effect of LCZ696 (sacubitril/valsartan) on amyloid-β concentrations in cerebrospinal fluid in healthy subjects. Br J Clin Pharmacol 2016; 81:878-90. [PMID: 26663387 PMCID: PMC4834603 DOI: 10.1111/bcp.12861] [Citation(s) in RCA: 80] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2015] [Revised: 11/16/2015] [Accepted: 12/08/2015] [Indexed: 12/11/2022] Open
Abstract
AIMS LCZ696 (angiotensin receptor neprilysin inhibitor) is a novel drug developed for the treatment of heart failure with reduced ejection fraction. Neprilysin is one of multiple enzymes degrading amyloid-β (Aβ). Its inhibition may increase Aβ levels. The potential exists that treatment of LCZ696, through the inhibition of neprilysin by LBQ657 (an LCZ696 metabolite), may result in accumulation of Aβ. The aim of this study was to assess the blood-brain-barrier penetration of LBQ657 and the potential effects of LCZ696 on cerebrospinal fluid (CSF) concentrations of Aβ isoforms in healthy human volunteers. METHODS In a double-blind, randomized, parallel group, placebo-controlled study, healthy subjects received once daily LCZ696 (400 mg, n = 21) or placebo (n = 22) for 14 days. RESULTS LCZ696 had no significant effect on CSF AUEC(0,36 h) of the aggregable Aβ species 1-42 or 1-40 compared with placebo (estimated treatment ratios 0.98 [95% CI 0.73, 1.34; P = 0.919] and 1.05 [95% CI 0.82, 1.34; P = 0.702], respectively). A 42% increase in CSF AUEC(0,36 h) of soluble Aβ 1-38 was observed (estimated treatment ratio 1.42 [95% CI 1.05, 1.91; P = 0.023]). CSF levels of LBQ657 and CSF Aβ 1-42, 1-40, and 1-38 concentrations were not related (r(2) values 0.022, 0.010, and 0.008, respectively). CONCLUSIONS LCZ696 did not cause changes in CSF levels of aggregable Aβ isoforms (1-42 and 1-40) compared with placebo, despite achieving CSF concentrations of LBQ657 sufficient to inhibit neprilysin. The clinical relevance of the increase in soluble CSF Aβ 1-38 is currently unknown.
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Affiliation(s)
- Thomas H. Langenickel
- Translational Medicine, Novartis Institutes for Biomedical ResearchNovartis Pharma AGBaselSwitzerland
| | - Chiaki Tsubouchi
- Translational Medicine, Novartis Institutes for Biomedical ResearchNovartis Pharma AGBaselSwitzerland
| | - Surya Ayalasomayajula
- Drug Metabolism and PharmacokineticsNovartis Institutes for Biomedical ResearchEast HanoverNew JerseyUSA
| | - Parasar Pal
- Biostatistical Sciences, Integrated Development Functions and RegionsNovartis Healthcare Pvt LtdHyderabadIndia
| | - Marie‐Anne Valentin
- Translational Medicine, Novartis Institutes for Biomedical ResearchNovartis Pharma AGBaselSwitzerland
| | - Markus Hinder
- Translational Medicine, Novartis Institutes for Biomedical ResearchNovartis Pharma AGBaselSwitzerland
| | | | - Hakop Gevorkyan
- California Clinical Trials Medical Group in Affiliation with PAREXEL InternationalGlendaleCaliforniaUSA
| | - Iris Rajman
- Translational Medicine, Novartis Institutes for Biomedical ResearchNovartis Pharma AGBaselSwitzerland
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26
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Feldman AM. Neprilysin Inhibition in the Time of Precision Medicine. JACC. HEART FAILURE 2016; 4:S2213-1779(16)30049-X. [PMID: 27107556 DOI: 10.1016/j.jchf.2016.02.016] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2016] [Accepted: 02/26/2016] [Indexed: 12/17/2022]
Affiliation(s)
- Arthur M Feldman
- Department of Medicine, Lewis Katz School of Medicine at Temple University, Philadelphia, Pennsylvania.
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27
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Khan JM, Khan MS, Ali MS, Al-Shabib NA, Khan RH. Cetyltrimethylammonium bromide (CTAB) promote amyloid fibril formation in carbohydrate binding protein (concanavalin A) at physiological pH. RSC Adv 2016. [DOI: 10.1039/c6ra03707k] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Low concentration of CTAB provoked cross β-sheet formation whereas high concentrations of CTAB direct to alpha helix induction in Con A.
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Affiliation(s)
- Javed Masood Khan
- Department of Food Science and Nutrition
- Faculty of Food and Agricultural Sciences
- King Saud University
- 2460 Riyadh 11451
- Saudi Arabia
| | - Mohd Shahnawaz Khan
- Protein Research Chair
- Department of Biochemistry
- College of Science
- King Saud University
- Riyadh
| | - Mohd Sajid Ali
- Department of Chemistry
- King Saud University
- Riyadh 11451
- Saudi Arabia
| | - Nasser Abdulatif Al-Shabib
- Department of Food Science and Nutrition
- Faculty of Food and Agricultural Sciences
- King Saud University
- 2460 Riyadh 11451
- Saudi Arabia
| | - Rizwan Hasan Khan
- Interdisciplinary Biotechnology Unit
- Aligarh Muslim University
- Aligarh
- India
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28
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Guan Y, Cao KJ, Cantlon A, Elbel K, Theodorakis EA, Walsh DM, Yang J, Shah JV. Real-Time Monitoring of Alzheimer's-Related Amyloid Aggregation via Probe Enhancement-Fluorescence Correlation Spectroscopy. ACS Chem Neurosci 2015. [PMID: 26212450 DOI: 10.1021/acschemneuro.5b00176] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
This work describes the use of fluorescence correlation spectroscopy (FCS) and a novel amyloid-binding fluorescent probe, ARCAM 1, to monitor the aggregation of the Alzheimer's disease-associated amyloid β-peptide (Aβ). ARCAM 1 exhibits a large increase in fluorescence emission upon binding to Aβ assemblies, making it an excellent candidate for probe enhancement FCS (PE-FCS). ARCAM 1 binding does not change Aβ aggregation kinetics. It also exhibits greater dynamic range as a probe in reporting aggregate size by FCS in Aβ, when compared to thioflavin T (ThT) or an Aβ peptide modified with a fluorophore. Using fluorescent burst analysis (via PE-FCS) to follow aggregation of Aβ, we detected soluble aggregates at significantly earlier time points compared to typical bulk fluorescence measurements. Autocorrelation analysis revealed the size of these early Aβ assemblies. These results indicate that PE-FCS/ARCAM 1 based assays can detect and provide size characterization of small Aβ aggregation intermediates during the assembly process, which could enable monitoring and study of such aggregates that transiently accumulate in biofluids of patients with Alzheimer's and other neurodegenerative diseases.
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Affiliation(s)
- Yinghua Guan
- Department
of Systems Biology, Harvard Medical School, Boston, Massachusetts 02115, United States
| | - Kevin J. Cao
- Department
of Chemistry and Biochemistry, University of California at San Diego, La
Jolla, California 92093-0358, United States
| | | | - Kristyna Elbel
- Department
of Chemistry and Biochemistry, University of California at San Diego, La
Jolla, California 92093-0358, United States
| | - Emmanuel A. Theodorakis
- Department
of Chemistry and Biochemistry, University of California at San Diego, La
Jolla, California 92093-0358, United States
| | | | - Jerry Yang
- Department
of Chemistry and Biochemistry, University of California at San Diego, La
Jolla, California 92093-0358, United States
| | - Jagesh V. Shah
- Department
of Systems Biology, Harvard Medical School, Boston, Massachusetts 02115, United States
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29
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Affiliation(s)
- Manish K. Tiwari
- DTU Chemistry Technical University of Denmark Kongens Lyngby Denmark
| | - Kasper P. Kepp
- DTU Chemistry Technical University of Denmark Kongens Lyngby Denmark
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30
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Ashraf GM, Greig NH, Khan TA, Hassan I, Tabrez S, Shakil S, Sheikh IA, Zaidi SK, Akram M, Jabir NR, Firoz CK, Naeem A, Alhazza IM, Damanhouri GA, Kamal MA. Protein misfolding and aggregation in Alzheimer's disease and type 2 diabetes mellitus. CNS & NEUROLOGICAL DISORDERS-DRUG TARGETS 2015; 13:1280-93. [PMID: 25230234 DOI: 10.2174/1871527313666140917095514] [Citation(s) in RCA: 108] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2014] [Revised: 05/11/2014] [Accepted: 05/12/2014] [Indexed: 12/27/2022]
Abstract
In general, proteins can only execute their various biological functions when they are appropriately folded. Their amino acid sequence encodes the relevant information required for correct three-dimensional folding, with or without the assistance of chaperones. The challenge associated with understanding protein folding is currently one of the most important aspects of the biological sciences. Misfolded protein intermediates form large polymers of unwanted aggregates and are involved in the pathogenesis of many human diseases, including Alzheimer's disease (AD) and Type 2 diabetes mellitus (T2DM). AD is one of the most prevalent neurological disorders and has worldwide impact; whereas T2DM is considered a metabolic disease that detrementally influences numerous organs, afflicts some 8% of the adult population, and shares many risk factors with AD. Research data indicates that there is a widespread conformational change in the proteins involved in AD and T2DM that form β-sheet like motifs. Although conformation of these β-sheets is common to many functional proteins, the transition from α-helix to β-sheet is a typical characteristic of amyloid deposits. Any abnormality in this transition results in protein aggregation and generation of insoluble fibrils. The abnormal and toxic proteins can interact with other native proteins and consequently catalyze their transition into the toxic state. Both AD and T2DM are prevalent in the aged population. AD is characterized by the accumulation of amyloid-β (Aβ) in brain, while T2DM is characterized by the deposition of islet amyloid polypeptide (IAPP, also known as amylin) within beta-cells of the pancreas. T2DM increases pathological angiogenesis and immature vascularisation. This also leads to chronic cerebral hypoperfusion, which results in dysfunction and degeneration of neuroglial cells. With an abundance of common mechanisms underpinning both disorders, a significant question that can be posed is whether T2DM leads to AD in aged individuals and the associations between other protein misfolding diseases.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | | | | | | | - Mohammad A Kamal
- King Fahd Medical Research Center, King Abdulaziz University, P. O. Box 80216, Jeddah 21589, Kingdom of Saudi Arabia.
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31
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Tiwari MK, Kepp KP. Modeling the Aggregation Propensity and Toxicity of Amyloid-β Variants. J Alzheimers Dis 2015; 47:215-29. [DOI: 10.3233/jad-150046] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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32
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Cantlon A, Frigerio CS, Freir DB, Boland B, Jin M, Walsh DM. The Familial British Dementia Mutation Promotes Formation of Neurotoxic Cystine Cross-linked Amyloid Bri (ABri) Oligomers. J Biol Chem 2015; 290:16502-16. [PMID: 25957407 DOI: 10.1074/jbc.m115.652263] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2015] [Indexed: 01/29/2023] Open
Abstract
Familial British dementia (FBD) is an inherited neurodegenerative disease believed to result from a mutation in the BRI2 gene. Post-translational processing of wild type BRI2 and FBD-BRI2 result in the production of a 23-residue long Bri peptide and a 34-amino acid long ABri peptide, respectively, and ABri is found deposited in the brains of individuals with FBD. Similarities in the neuropathology and clinical presentation shared by FBD and Alzheimer disease (AD) have led some to suggest that ABri and the AD-associated amyloid β-protein (Aβ) are molecular equivalents that trigger analogous pathogenic cascades. But the sequences and innate properties of ABri and Aβ are quite different, notably ABri contains two cysteine residues that can form disulfide bonds. Thus we sought to determine whether ABri was neurotoxic and if this activity was regulated by oxidation and/or aggregation. Crucially, the type of oxidative cross-linking dramatically influenced both ABri aggregation and toxicity. Cyclization of Bri and ABri resulted in production of biologically inert monomers that showed no propensity to assemble, whereas reduced ABri and reduced Bri aggregated forming thioflavin T-positive amyloid fibrils that lacked significant toxic activity. ABri was more prone to form inter-molecular disulfide bonds than Bri and the formation of covalently stabilized ABri oligomers was associated with toxicity. These results suggest that extension of the C-terminal of Bri causes a shift in the type of disulfide bonds formed and that structures built from covalently cross-linked oligomers can interact with neurons and compromise their function and viability.
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Affiliation(s)
- Adam Cantlon
- From the Laboratory for Neurodegenerative Research, School of Biomolecular and Biomedical Science, Conway Institute, University College Dublin, Belfield, Dublin 4, Republic of Ireland and the Laboratory for Neurodegenerative Research, Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts 02115
| | - Carlo Sala Frigerio
- From the Laboratory for Neurodegenerative Research, School of Biomolecular and Biomedical Science, Conway Institute, University College Dublin, Belfield, Dublin 4, Republic of Ireland and
| | - Darragh B Freir
- From the Laboratory for Neurodegenerative Research, School of Biomolecular and Biomedical Science, Conway Institute, University College Dublin, Belfield, Dublin 4, Republic of Ireland and
| | - Barry Boland
- From the Laboratory for Neurodegenerative Research, School of Biomolecular and Biomedical Science, Conway Institute, University College Dublin, Belfield, Dublin 4, Republic of Ireland and
| | - Ming Jin
- the Laboratory for Neurodegenerative Research, Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts 02115
| | - Dominic M Walsh
- the Laboratory for Neurodegenerative Research, Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts 02115
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33
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Arosio P, Knowles TPJ, Linse S. On the lag phase in amyloid fibril formation. Phys Chem Chem Phys 2015; 17:7606-18. [PMID: 25719972 PMCID: PMC4498454 DOI: 10.1039/c4cp05563b] [Citation(s) in RCA: 521] [Impact Index Per Article: 57.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2014] [Accepted: 02/03/2015] [Indexed: 12/11/2022]
Abstract
The formation of nanoscale amyloid fibrils from normally soluble peptides and proteins is a common form of self-assembly phenomenon that has fundamental connections with biological functions and human diseases. The kinetics of this process has been widely studied and exhibits on a macroscopic level three characteristic stages: a lag phase, a growth phase and a final plateau regime. The question of which molecular events take place during each one of these phases has been a central element in the quest for a mechanism of amyloid formation. In this review, we discuss the nature and molecular origin of the lag-phase in amyloid formation by making use of tools and concepts from physical chemistry, in particular from chemical reaction kinetics. We discuss how, in macroscopic samples, it has become apparent that the lag-phase is not a waiting time for nuclei to form. Rather, multiple parallel processes exist and typically millions of primary nuclei form during the lag phase from monomers in solution. Thus, the lag-time represents a time that is required for the nuclei that are formed early on in the reaction to grow and proliferate in order to reach an aggregate concentration that is readily detected in bulk assays. In many cases, this proliferation takes place through secondary nucleation, where fibrils may present a catalytic surface for the formation of new aggregates. Fibrils may also break (fragmentation) and thereby provide new ends for elongation. Thus, at least two - primary nucleation and elongation - and in many systems at least four - primary nucleation, elongation, secondary nucleation and fragmentation - microscopic processes occur during the lag phase. Moreover, these same processes occur during all three phases of the macroscopic aggregation process, albeit at different rates as governed by rate constants and by the concentration of reacting species at each point in time.
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Affiliation(s)
- Paolo Arosio
- Chemistry Department , University of Cambridge , Lensfield road , Cambridge , UK
| | - Tuomas P. J. Knowles
- Chemistry Department , University of Cambridge , Lensfield road , Cambridge , UK
| | - Sara Linse
- Department of Biochemistry and Structural Biology , Chemical Centre , Lund University , P. O. Box 124 , SE221 00 Lund , Sweden .
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34
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Baranello RJ, Bharani KL, Padmaraju V, Chopra N, Lahiri DK, Greig NH, Pappolla MA, Sambamurti K. Amyloid-beta protein clearance and degradation (ABCD) pathways and their role in Alzheimer's disease. Curr Alzheimer Res 2015; 12:32-46. [PMID: 25523424 PMCID: PMC4820400 DOI: 10.2174/1567205012666141218140953] [Citation(s) in RCA: 210] [Impact Index Per Article: 23.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2014] [Revised: 11/16/2014] [Accepted: 12/05/2014] [Indexed: 11/22/2022]
Abstract
Amyloid-β proteins (Aβ) of 42 (Aβ42) and 40 aa (Aβ40) accumulate as senile plaques (SP) and cerebrovascular amyloid protein deposits that are defining diagnostic features of Alzheimer's disease (AD). A number of rare mutations linked to familial AD (FAD) on the Aβ precursor protein (APP), Presenilin-1 (PS1), Presenilin- 2 (PS2), Adamalysin10, and other genetic risk factors for sporadic AD such as the ε4 allele of Apolipoprotein E (ApoE-ε4) foster the accumulation of Aβ and also induce the entire spectrum of pathology associated with the disease. Aβ accumulation is therefore a key pathological event and a prime target for the prevention and treatment of AD. APP is sequentially processed by β-site APP cleaving enzyme (BACE1) and γ-secretase, a multisubunit PS1/PS2-containing integral membrane protease, to generate Aβ. Although Aβ accumulates in all forms of AD, the only pathways known to be affected in FAD increase Aβ production by APP gene duplication or via base substitutions on APP and γ-secretase subunits PS1 and PS2 that either specifically increase the yield of the longer Aβ42 or both Aβ40 and Aβ42. However, the vast majority of AD patients accumulate Aβ without these known mutations. This led to proposals that impairment of Aβ degradation or clearance may play a key role in AD pathogenesis. Several candidate enzymes, including Insulin-degrading enzyme (IDE), Neprilysin (NEP), Endothelin-converting enzyme (ECE), Angiotensin converting enzyme (ACE), Plasmin, and Matrix metalloproteinases (MMPs) have been identified and some have even been successfully evaluated in animal models. Several studies also have demonstrated the capacity of γ-secretase inhibitors to paradoxically increase the yield of Aβ and we have recently established that the mechanism is by skirting Aβ degradation. This review outlines major cellular pathways of Aβ degradation to provide a basis for future efforts to fully characterize the panel of pathways responsible for Aβ turnover.
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Affiliation(s)
| | | | | | | | | | | | | | - Kumar Sambamurti
- Department of Neurosciences, Medical University of South Carolina, 173 Ashley Avenue, BSB 403, Charleston, SC 29425, USA.
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35
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Aβ dimers differ from monomers in structural propensity, aggregation paths and population of synaptotoxic assemblies. Biochem J 2014; 461:413-26. [PMID: 24785004 DOI: 10.1042/bj20140219] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Dimers of Aβ (amyloid β-protein) are believed to play an important role in Alzheimer's disease. In the absence of sufficient brain-derived dimers, we studied one of the only possible dimers that could be produced in vivo, [Aβ](DiY) (dityrosine cross-linked Aβ). For comparison, we used the Aβ monomer and a design dimer cross-linked by replacement of Ser²⁶ with cystine [AβS26C]₂. We showed that similar to monomers, unaggregated dimers lack appreciable structure and fail to alter long-term potentiation. Importantly, dimers exhibit subtly different structural propensities from monomers and each other, and can self-associate to form larger assemblies. Although [Aβ](DiY) and [AβS26C]₂ have distinct aggregation pathways, they both populate bioactive soluble assemblies for longer durations than Aβ monomers. Our results indicate that the link between Aβ dimers and Alzheimer's disease results from the ability of dimers to further assemble and form synaptotoxic assemblies that persist for long periods of time.
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36
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Spencer B, Verma I, Desplats P, Morvinski D, Rockenstein E, Adame A, Masliah E. A neuroprotective brain-penetrating endopeptidase fusion protein ameliorates Alzheimer disease pathology and restores neurogenesis. J Biol Chem 2014; 289:17917-31. [PMID: 24825898 DOI: 10.1074/jbc.m114.557439] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Alzheimer disease (AD) is characterized by widespread neurodegeneration throughout the association cortex and limbic system, deposition of amyloid-β peptide (Aβ) in the neuropil and around the blood vessels, and formation of neurofibrillary tangles. The endopeptidase neprilysin has been successfully used to reduce the accumulation of Aβ following intracranial viral vector delivery or ex vivo manipulated intracranial delivery. These therapies have relied on direct injections into the brain, whereas a clinically desirable therapy would involve i.v. infusion of a recombinant enzyme. We previously characterized a recombinant neprilysin that contained a 38-amino acid brain-targeting domain. Recombinant cell lines have been generated expressing this brain-targeted enzyme (ASN12). In this report, we characterize the ASN12 recombinant protein for pharmacology in a mouse as well as efficacy in two APPtg mouse models of AD. The recombinant ASN12 transited to the brain with a t½ of 24 h and accumulated to 1.7% of injected dose at 24 h following i.v. delivery. We examined pharmacodynamics in the tg2576 APPtg mouse with the prion promoter APP695 SWE mutation and in the Line41 mThy1 APP751 mutation mouse. Treatment of either APPtg mouse resulted in reduced Aβ, increased neuronal synapses, and improved learning and memory. In addition, the Line41 APPtg mice showed increased levels of C-terminal neuropeptide Y fragments and increased neurogenesis. These results suggest that the recombinant brain-targeted neprilysin, ASN12, may be an effective treatment for AD and warrant further investigation in clinical trials.
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Affiliation(s)
- Brian Spencer
- From the NeuroTransit, Inc., San Diego, California 92121,
| | - Inder Verma
- the Laboratory of Genetics, Salk Institute for Biological Studies, La Jolla, California 92037, and
| | | | - Dinorah Morvinski
- the Laboratory of Genetics, Salk Institute for Biological Studies, La Jolla, California 92037, and
| | | | | | - Eliezer Masliah
- the Departments of Neuroscience and Pathology, University of California at San Diego, San Diego, California 92093
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37
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Pope D, Madura JD, Cascio M. β-Amyloid and neprilysin computational studies identify critical residues implicated in binding specificity. J Chem Inf Model 2014; 54:1157-65. [PMID: 24650257 DOI: 10.1021/ci500015m] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
The zinc metalloprotease neprilysin (NEP) promiscuously degrades small bioactive peptides. NEP is among a select group of metalloenzymes that degrade the amyloid beta-peptide (Aβ) in vivo and in situ. Since accumulation of neurotoxic Aβ aggregates in the brain appears to be a causative agent in the pathophysiology of Alzheimer's disease (AD), increased clearance of Aβ resulting from overexpression of NEP exhibits therapeutic potential for AD. However, higher NEP peptidase activity may be harmful without an increased specificity for Aβ over other competing substrates. Crystal structures of NEP-inhibitor complexes and their characterization have highlighted potential amino acid interactions involved in substrate binding and are used as templates to guide our methodology in docking Aβ in NEP. Results from protein-ligand docking calculations predict S2' subsite residues Arg 102 and Arg 110 of NEP participate in specific interactions with Aβ. These interactions provide insight into developing NEP specificity for Aβ.
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Affiliation(s)
- Darrick Pope
- Department of Chemistry and Biochemistry and Center for Computational Sciences, Duquesne University , 600 Forbes Avenue, 331 Mellon Hall, Pittsburgh, Pennsylvania 15282, United States
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38
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Tang TC, Hu Y, Kienlen-Campard P, El Haylani L, Decock M, Van Hees J, Fu Z, Octave JN, Constantinescu SN, Smith SO. Conformational changes induced by the A21G Flemish mutation in the amyloid precursor protein lead to increased Aβ production. Structure 2014; 22:387-96. [PMID: 24462250 DOI: 10.1016/j.str.2013.12.012] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2013] [Revised: 12/11/2013] [Accepted: 12/12/2013] [Indexed: 01/11/2023]
Abstract
Proteolysis of the β C-terminal fragment (β-CTF) of the amyloid precursor protein generates the Aβ peptides associated with Alzheimer's disease. Familial mutations in the β-CTF, such as the A21G Flemish mutation, can increase Aβ secretion. We establish how the Flemish mutation alters the structure of C55, the first 55 residues of the β-CTF, using FTIR and solid-state NMR spectroscopy. We show that the A21G mutation reduces β sheet structure of C55 from Leu17 to Ala21, an inhibitory region near the site of the mutation, and increases α-helical structure from Gly25 to Gly29, in a region near the membrane surface and thought to interact with cholesterol. Cholesterol also increases Aβ peptide secretion, and we show that the incorporation of cholesterol into model membranes enhances the structural changes induced by the Flemish mutant, suggesting a common link between familial mutations and the cellular environment.
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Affiliation(s)
- Tzu-Chun Tang
- Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, NY 11794-5215, USA
| | - Yi Hu
- Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, NY 11794-5215, USA
| | | | - Laetitia El Haylani
- Institute of Neuroscience, Université catholique de Louvain, Brussels 1200, Belgium
| | - Marie Decock
- Institute of Neuroscience, Université catholique de Louvain, Brussels 1200, Belgium
| | - Joanne Van Hees
- Ludwig Institute for Cancer Research and de Duve Institute, Université catholique de Louvain, Brussels 1200, Belgium
| | - Ziao Fu
- Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, NY 11794-5215, USA
| | - Jean-Noel Octave
- Institute of Neuroscience, Université catholique de Louvain, Brussels 1200, Belgium
| | - Stefan N Constantinescu
- Ludwig Institute for Cancer Research and de Duve Institute, Université catholique de Louvain, Brussels 1200, Belgium
| | - Steven O Smith
- Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, NY 11794-5215, USA.
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39
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Grimm MOW, Mett J, Stahlmann CP, Haupenthal VJ, Zimmer VC, Hartmann T. Neprilysin and Aβ Clearance: Impact of the APP Intracellular Domain in NEP Regulation and Implications in Alzheimer's Disease. Front Aging Neurosci 2013; 5:98. [PMID: 24391587 PMCID: PMC3870290 DOI: 10.3389/fnagi.2013.00098] [Citation(s) in RCA: 96] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2013] [Accepted: 12/09/2013] [Indexed: 12/18/2022] Open
Abstract
One of the characteristic hallmarks of Alzheimer's disease (AD) is an accumulation of amyloid β (Aβ) leading to plaque formation and toxic oligomeric Aβ complexes. Besides the de novo synthesis of Aβ caused by amyloidogenic processing of the amyloid precursor protein (APP), Aβ levels are also highly dependent on Aβ degradation. Several enzymes are described to cleave Aβ. In this review we focus on one of the most prominent Aβ degrading enzymes, the zinc-metalloprotease Neprilysin (NEP). In the first part of the review we discuss beside the general role of NEP in Aβ degradation the alterations of the enzyme observed during normal aging and the progression of AD. In vivo and cell culture experiments reveal that a decreased NEP level results in an increased Aβ level and vice versa. In a pathological situation like AD, it has been reported that NEP levels and activity are decreased and it has been suggested that certain polymorphisms in the NEP gene result in an increased risk for AD. Conversely, increasing NEP activity in AD mouse models revealed an improvement in some behavioral tests. Therefore it has been suggested that increasing NEP might be an interesting potential target to treat or to be protective for AD making it indispensable to understand the regulation of NEP. Interestingly, it is discussed that the APP intracellular domain (AICD), one of the cleavage products of APP processing, which has high similarities to Notch receptor processing, might be involved in the transcriptional regulation of NEP. However, the mechanisms of NEP regulation by AICD, which might be helpful to develop new therapeutic strategies, are up to now controversially discussed and summarized in the second part of this review. In addition, we review the impact of AICD not only in the transcriptional regulation of NEP but also of further genes.
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Affiliation(s)
- Marcus O W Grimm
- Experimental Neurology, Saarland University , Homburg, Saar , Germany ; Neurodegeneration and Neurobiology, Saarland University , Homburg, Saar , Germany ; Deutsches Institut für DemenzPrävention, Saarland University , Homburg, Saar , Germany
| | - Janine Mett
- Experimental Neurology, Saarland University , Homburg, Saar , Germany
| | | | | | - Valerie C Zimmer
- Experimental Neurology, Saarland University , Homburg, Saar , Germany
| | - Tobias Hartmann
- Experimental Neurology, Saarland University , Homburg, Saar , Germany ; Neurodegeneration and Neurobiology, Saarland University , Homburg, Saar , Germany ; Deutsches Institut für DemenzPrävention, Saarland University , Homburg, Saar , Germany
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40
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Jiang J, Golchert KJ, Kingsley CN, Brubaker WD, Martin RW, Mukamel S. Exploring the aggregation propensity of γS-crystallin protein variants using two-dimensional spectroscopic tools. J Phys Chem B 2013; 117:14294-301. [PMID: 24219230 DOI: 10.1021/jp408000k] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The formation of amyloid fibrils is associated with many serious diseases as well as diverse biological functions. Despite the importance of these aggregates, predicting the aggregation propensity of a particular sequence is a major challenge. We report a joint 2D nuclear magnetic resonance (NMR) and ultraviolet (2DUV) study of fibrillization in the wild-type and two aggregation-prone mutants of the eye lens protein γS-crystallin. Simulations show that the complexity of 2DUV signals as measured by their "approximate entropy" is a good indicator for the conformational entropy and in turn is strongly correlated with its aggregation propensity. These findings are in agreement with high-resolution NMR experiments and are corroborated for amyloid fibrils. The 2DUV technique is complementary to high-resolution structural methods and has the potential to make the evaluation of the aggregation propensity for protein variant propensity of protein structure more accessible to both theory and experiment. The approximate entropy of experimental 2DUV signals can be used for fast screening, enabling identification of variants with high fibrillization propensity for the much more time-consuming NMR structural studies, potentially expediting the characterization of protein variants associated with cataract and other protein aggregation diseases.
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Affiliation(s)
- Jun Jiang
- Department of Chemical Physics, University of Science and Technology of China , Hefei, China
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41
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Nisbet RM, Nuttall SD, Robert R, Caine JM, Dolezal O, Hattarki M, Pearce LA, Davydova N, Masters CL, Varghese JN, Streltsov VA. Structural studies of the tethered N-terminus of the Alzheimer's disease amyloid-β peptide. Proteins 2013; 81:1748-58. [PMID: 23609990 DOI: 10.1002/prot.24312] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2013] [Revised: 03/28/2013] [Accepted: 04/03/2013] [Indexed: 01/13/2023]
Abstract
Alzheimer's disease is the most common form of dementia in humans and is related to the accumulation of the amyloid-β (Aβ) peptide and its interaction with metals (Cu, Fe, and Zn) in the brain. Crystallographic structural information about Aβ peptide deposits and the details of the metal-binding site is limited owing to the heterogeneous nature of aggregation states formed by the peptide. Here, we present a crystal structure of Aβ residues 1-16 fused to the N-terminus of the Escherichia coli immunity protein Im7, and stabilized with the fragment antigen binding fragment of the anti-Aβ N-terminal antibody WO2. The structure demonstrates that Aβ residues 10-16, which are not in complex with the antibody, adopt a mixture of local polyproline II-helix and turn type conformations, enhancing cooperativity between the two adjacent histidine residues His13 and His14. Furthermore, this relatively rigid region of Aβ (residues, 10-16) appear as an almost independent unit available for trapping metal ions and provides a rationale for the His13-metal-His14 coordination in the Aβ1-16 fragment implicated in Aβ metal binding. This novel structure, therefore, has the potential to provide a foundation for investigating the effect of metal ion binding to Aβ and illustrates a potential target for the development of future Alzheimer's disease therapeutics aimed at stabilizing the N-terminal monomer structure, in particular residues His13 and His14, and preventing Aβ metal-binding-induced neurotoxicity.
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Affiliation(s)
- Rebecca M Nisbet
- Materials Science and Engineering & Preventative Health Flagship, CSIRO, Parkville, Victoria, 3052, Australia
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42
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Shahnawaz M, Sharoar MG, Shin SY, Park IS. Wild-type, Flemish, and Dutch amyloid-β
exhibit different cytotoxicities depending on Aβ
40 to Aβ
42 interaction time and concentration ratio. J Pept Sci 2013; 19:545-53. [DOI: 10.1002/psc.2531] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2013] [Revised: 05/03/2013] [Accepted: 05/26/2013] [Indexed: 11/10/2022]
Affiliation(s)
- Md. Shahnawaz
- Department of Bio-materials Engineering; College of Medicine, Chosun University; Gwangju 501-759 Korea
- Medical School; The University of Texas Health Science Center at Houston; 6431 Fannin St Houston TX 77030 USA
| | - Md. Golam Sharoar
- Department of Bio-materials Engineering; College of Medicine, Chosun University; Gwangju 501-759 Korea
- Department of Genetic Engineering and Biotechnology; University of Rajshahi; Rajshahi 6205 Bangladesh
| | - Song Yub Shin
- Department of Bio-materials Engineering; College of Medicine, Chosun University; Gwangju 501-759 Korea
- Department of Cell and Molecular Biology; College of Medicine, Chosun University; Gwangju 501-759 Korea
| | - Il-Seon Park
- Department of Bio-materials Engineering; College of Medicine, Chosun University; Gwangju 501-759 Korea
- Department of Cell and Molecular Biology; College of Medicine, Chosun University; Gwangju 501-759 Korea
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43
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Saido T, Leissring MA. Proteolytic degradation of amyloid β-protein. Cold Spring Harb Perspect Med 2013; 2:a006379. [PMID: 22675659 DOI: 10.1101/cshperspect.a006379] [Citation(s) in RCA: 253] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The amyloid β-protein (Aβ) is subject to proteolytic degradation by a diverse array of peptidases and proteinases, known collectively as Aβ-degrading proteases (AβDPs). A growing number of AβDPs have been identified, which, under physiological and/or pathophysiological conditions, contribute significantly to the determination of endogenous cerebral Aβ levels. Despite more than a decade of investigation, the complete set of AβDPs remains to be established, and our understanding of even well-established AβDPs is incomplete. Nevertheless, the study of known AβDPs has contributed importantly to our understanding of the molecular pathogenesis of Alzheimer disease (AD) and has inspired the development of several novel therapeutic approaches to the regulation of cerebral Aβ levels. In this article, we discuss the general features of Aβ degradation and introduce the best-characterized AβDPs, focusing on their diverse properties and the numerous conceptual insights that have emerged from the study of each.
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Affiliation(s)
- Takaomi Saido
- Riken Brain Science Institute, Saitamo 351-0198, Japan
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44
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Mahmoudi M, Quinlan-Pluck F, Monopoli MP, Sheibani S, Vali H, Dawson KA, Lynch I. Influence of the physiochemical properties of superparamagnetic iron oxide nanoparticles on amyloid β protein fibrillation in solution. ACS Chem Neurosci 2013; 4:475-85. [PMID: 23509983 DOI: 10.1021/cn300196n] [Citation(s) in RCA: 96] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Superparamagnetic iron oxide nanoparticles (SPIONs) are recognized as promising nanodiagnostic materials due to their biocompatibility, unique magnetic properties, and their application as multimodal contrast agents. As coated SPIONs have potential use in the diagnosis and treatment of various brain diseases such as Alzheimer's, a comprehensive understanding of their interactions with Aβ and other amyloidogenic proteins is essential prior to their clinical application. Here we demonstrate the effect of thickness and surface charge of the coating layer of SPIONs on the kinetics of fibrillation of Aβ in aqueous solution. A size and surface area dependent "dual" effect on Aβ fibrillation was observed. While lower concentrations of SPIONs inhibited fibrillation, higher concentrations increased the rate of Aβ fibrillation. With respect to coating charge, it is evident that the positively charged SPIONs are capable of promoting fibrillation at significantly lower particle concentrations compared with negatively charged or uncharged SPIONs. This suggests that in addition to the presence of particles, which affect the concentration of monomeric protein in solution (and thereby the nucleation time), there are also effects of binding on the protein conformation.
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Affiliation(s)
| | - Fiona Quinlan-Pluck
- Centre for BioNano Interactions, School of Chemistry and Chemical Biology, & Conway Institute of Biomolecular and Biomedical Sciences University College Dublin, Belfield, Dublin 4, Ireland
| | - Marco P. Monopoli
- Centre for BioNano Interactions, School of Chemistry and Chemical Biology, & Conway Institute of Biomolecular and Biomedical Sciences University College Dublin, Belfield, Dublin 4, Ireland
| | - Sara Sheibani
- Department of Chemistry and
Chemical Engineering, Royal Military College, Kingston, Ontario K7K 7B4, Canada
| | - Hojatollah Vali
- Department of Anatomy and Cell Biology, McGill University, Montreal, Canada
| | - Kenneth A. Dawson
- Centre for BioNano Interactions, School of Chemistry and Chemical Biology, & Conway Institute of Biomolecular and Biomedical Sciences University College Dublin, Belfield, Dublin 4, Ireland
| | - Iseult Lynch
- Centre for BioNano Interactions, School of Chemistry and Chemical Biology, & Conway Institute of Biomolecular and Biomedical Sciences University College Dublin, Belfield, Dublin 4, Ireland
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45
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Cheng XR, Hau BYH, Veloso AJ, Martic S, Kraatz HB, Kerman K. Surface Plasmon Resonance Imaging of Amyloid-β Aggregation Kinetics in the Presence of Epigallocatechin Gallate and Metals. Anal Chem 2013; 85:2049-55. [DOI: 10.1021/ac303181q] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Xin R. Cheng
- Department
of Physical and Environmental
Sciences, University of Toronto Scarborough, Toronto, Ontario M1C 1A4, Canada
| | - Ben Y. H. Hau
- Department
of Physical and Environmental
Sciences, University of Toronto Scarborough, Toronto, Ontario M1C 1A4, Canada
| | - Anthony J. Veloso
- Department
of Physical and Environmental
Sciences, University of Toronto Scarborough, Toronto, Ontario M1C 1A4, Canada
| | - Sanela Martic
- Department of Chemistry and
Biochemistry, Oakland University, Rochester,
Michigan 48309, United States
| | - Heinz-Bernhard Kraatz
- Department
of Physical and Environmental
Sciences, University of Toronto Scarborough, Toronto, Ontario M1C 1A4, Canada
| | - Kagan Kerman
- Department
of Physical and Environmental
Sciences, University of Toronto Scarborough, Toronto, Ontario M1C 1A4, Canada
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46
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Abstract
The overproduction of β-amyloid (Aβ) fragments in transgenic APPswe/PS1dE9 mice results in formation of amyloid deposits in the cerebral cortex and hippocampus starting around four months of age and leading to cognitive impairment much later. We have previously found an age and transgene-dependent weakening of muscarinic receptor-mediated transmission that was not present in young (6-10-week-old) animals but preceded both amyloid deposits and cognitive deficits. Now we investigated immediate and prolonged in vitro effects of non-aggregated Aβ(1-42) on coupling of individual muscarinic receptor subtypes expressed in CHO (Chinese hamster ovary) cells and their underlying mechanisms. Immediate application of 1 μM Aβ(1-42) had no effect on the binding of the muscarinic antagonist N-methylscopolamine or the agonist carbachol. In contrast, 4-day treatment of CHO cells expressing the M1 muscarinic receptor with 100 nM Aβ(1-42) significantly changed the binding characteristics of the muscarinic agonist carbachol and reduced the extent of the M1 receptor-stimulated breakdown of phosphatidylinositol while it did not demonstrate overt toxic effects. The treatment had no influence on the expression of either G-proteins or muscarinic receptors. In concert, we found no change in the gene expression of muscarinic receptor subtypes and gene or protein expression of the G(s), G(q/11), and G(i/o) G-proteins in the cerebral cortex of young adult APPswe/PS1dE9 mice that demonstrate high concentrations of soluble Aβ(1-42) and impaired muscarinic receptor-mediated G-protein activation. Our results provide strong evidence that the initial injurious effects of Aβ(1-42) on M1 muscarinic receptor-mediated transmissionis is due to compromised coupling of the receptor with G(q/11) G-protein.
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47
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Welzel AT, Williams AD, McWilliams-Koeppen HP, Acero L, Weber A, Blinder V, Mably A, Bunk S, Hermann C, Farrell MA, Ehrlich HJ, Schwarz HP, Walsh DM, Solomon A, O’Nuallain B. Human anti-Aβ IgGs target conformational epitopes on synthetic dimer assemblies and the AD brain-derived peptide. PLoS One 2012; 7:e50317. [PMID: 23209707 PMCID: PMC3507685 DOI: 10.1371/journal.pone.0050317] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2012] [Accepted: 10/18/2012] [Indexed: 01/08/2023] Open
Abstract
Soluble non-fibrillar assemblies of amyloid-beta (Aβ) and aggregated tau protein are the proximate synaptotoxic species associated with Alzheimer's disease (AD). Anti-Aβ immunotherapy is a promising and advanced therapeutic strategy, but the precise Aβ species to target is not yet known. Previously, we and others have shown that natural human IgGs (NAbs) target diverse Aβ conformers and have therapeutic potential. We now demonstrate that these antibodies bound with nM avidity to conformational epitopes on plate-immobilized synthetic Aβ dimer assemblies, including synaptotoxic protofibrils, and targeted these conformers in solution. Importantly, NAbs also recognized Aβ extracted from the water-soluble phase of human AD brain, including species that migrated on denaturing PAGE as SDS-stable dimers. The critical reliance on Aβ's conformational state for NAb binding, and not a linear sequence epitope, was confirmed by the antibody's nM reactivity with plate-immobilized protofibrills, and weak uM binding to synthetic Aβ monomers and peptide fragments. The antibody's lack of reactivity against a linear sequence epitope was confirmed by our ability to isolate anti-Aβ NAbs from intravenous immunoglobulin using affinity matrices, immunoglobulin light chain fibrils and Cibacron blue, which had no sequence similarity with the peptide. These findings suggest that further investigations on the molecular basis and the therapeutic/diagnostic potential of anti-Aβ NAbs are warranted.
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Affiliation(s)
- Alfred T. Welzel
- The Conway Institute, University College Dublin, Belfield, Dublin, Republic of Ireland
| | - Angela D. Williams
- Human Immunology and Cancer Program, Department of Medicine, University of Tennessee Graduate School of Medicine, Knoxville, Tennessee, United States of America
| | - Helen P. McWilliams-Koeppen
- Human Immunology and Cancer Program, Department of Medicine, University of Tennessee Graduate School of Medicine, Knoxville, Tennessee, United States of America
| | - Luis Acero
- Human Immunology and Cancer Program, Department of Medicine, University of Tennessee Graduate School of Medicine, Knoxville, Tennessee, United States of America
| | | | - Veronika Blinder
- The Laboratory of Neurodegenerative Research, Brigham and Women’s Hospital, Harvard Institutes of Medicine, Boston, Massachusetts, United States of America
| | - Alex Mably
- The Conway Institute, University College Dublin, Belfield, Dublin, Republic of Ireland
- The Laboratory of Neurodegenerative Research, Brigham and Women’s Hospital, Harvard Institutes of Medicine, Boston, Massachusetts, United States of America
| | | | | | - Michael A. Farrell
- Dublin Brain Bank, Pathology Department, Beaumont Hospital, Dublin, Ireland
| | | | | | - Dominic M. Walsh
- The Conway Institute, University College Dublin, Belfield, Dublin, Republic of Ireland
- The Laboratory of Neurodegenerative Research, Brigham and Women’s Hospital, Harvard Institutes of Medicine, Boston, Massachusetts, United States of America
| | - Alan Solomon
- Human Immunology and Cancer Program, Department of Medicine, University of Tennessee Graduate School of Medicine, Knoxville, Tennessee, United States of America
| | - Brian O’Nuallain
- The Conway Institute, University College Dublin, Belfield, Dublin, Republic of Ireland
- Human Immunology and Cancer Program, Department of Medicine, University of Tennessee Graduate School of Medicine, Knoxville, Tennessee, United States of America
- The Laboratory of Neurodegenerative Research, Brigham and Women’s Hospital, Harvard Institutes of Medicine, Boston, Massachusetts, United States of America
- * E-mail:
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48
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Gessel MM, Bernstein S, Kemper M, Teplow DB, Bowers MT. Familial Alzheimer's disease mutations differentially alter amyloid β-protein oligomerization. ACS Chem Neurosci 2012; 3:909-18. [PMID: 23173071 DOI: 10.1021/cn300050d] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2012] [Accepted: 06/26/2012] [Indexed: 11/30/2022] Open
Abstract
Although most cases of Alzheimer's disease (AD) are sporadic, ∼5% of cases are genetic in origin. These cases, known as familial Alzheimer's disease (FAD), are caused by mutations that alter the rate of production or the primary structure of the amyloid β-protein (Aβ). Changes in the primary structure of Aβ alter the peptide's assembly and toxic activity. Recently, a primary working hypothesis for AD has evolved where causation has been attributed to early, soluble peptide oligomer states. Here we posit that both experimental and pathological differences between FAD-related mutants and wild-type Aβ could be reflected in the early oligomer distributions of these peptides. We use ion mobility-based mass spectrometry to probe the structure and early aggregation states of three mutant forms of Aβ40 and Aβ42: Tottori (D7N), Flemish (A21G), and Arctic (E22G). Our results indicate that the FAD-related amino acid substitutions have no noticeable effect on Aβ monomer cross section, indicating there are no major structural changes in the monomers. However, we observe significant changes to the aggregation states populated by the various Aβ mutants, indicating that structural changes present in the monomers are reflected in the oligomers. Moreover, the early oligomer distributions differ for each mutant, suggesting a possible structural basis for the varied pathogenesis of different forms of FAD.
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Affiliation(s)
- Megan Murray Gessel
- Department
of Chemistry and
Biochemistry, University of California, Santa Barbara, California 93106, United States
| | - Summer Bernstein
- Department
of Chemistry and
Biochemistry, University of California, Santa Barbara, California 93106, United States
| | - Martin Kemper
- Department
of Chemistry and
Biochemistry, University of California, Santa Barbara, California 93106, United States
| | - David B. Teplow
- Department of Neurology, David
Geffen School of Medicine at UCLA, Mary S. Easton Center for Alzheimer’s
Disease Research at UCLA, and Brain Research Institute and Molecular
Biology Institute, University of California at Los Angeles, Los Angeles, California 90095, United States
| | - Michael T. Bowers
- Department
of Chemistry and
Biochemistry, University of California, Santa Barbara, California 93106, United States
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49
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Vandersteen A, Hubin E, Sarroukh R, De Baets G, Schymkowitz J, Rousseau F, Subramaniam V, Raussens V, Wenschuh H, Wildemann D, Broersen K. A comparative analysis of the aggregation behavior of amyloid-β peptide variants. FEBS Lett 2012; 586:4088-93. [PMID: 23103738 DOI: 10.1016/j.febslet.2012.10.022] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2012] [Revised: 10/02/2012] [Accepted: 10/10/2012] [Indexed: 01/18/2023]
Abstract
Aggregated forms of the amyloid-β peptide are hypothesized to act as the prime toxic agents in Alzheimer disease (AD). The in vivo amyloid-β peptide pool consists of both C- and N-terminally truncated or mutated peptides, and the composition thereof significantly determines AD risk. Other variations, such as biotinylation, are introduced as molecular tools to aid the understanding of disease mechanisms. Since these modifications have the potential to alter key aggregation properties of the amyloid-β peptide, we present a comparative study of the aggregation of a substantial set of the most common in vivo identified and in vitro produced amyloid-β peptides.
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Affiliation(s)
- Annelies Vandersteen
- 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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50
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Kaden D, Harmeier A, Weise C, Munter LM, Althoff V, Rost BR, Hildebrand PW, Schmitz D, Schaefer M, Lurz R, Skodda S, Yamamoto R, Arlt S, Finckh U, Multhaup G. Novel APP/Aβ mutation K16N produces highly toxic heteromeric Aβ oligomers. EMBO Mol Med 2012; 4:647-59. [PMID: 22514144 PMCID: PMC3407951 DOI: 10.1002/emmm.201200239] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2011] [Revised: 03/01/2012] [Accepted: 03/02/2012] [Indexed: 12/04/2022] Open
Abstract
Here, we describe a novel missense mutation in the amyloid precursor protein (APP) causing a lysine-to-asparagine substitution at position 687 (APP770; herein, referred to as K16N according to amyloid-β (Aβ) numbering) resulting in an early onset dementia with an autosomal dominant inheritance pattern. The K16N mutation is located exactly at the α-secretase cleavage site and influences both APP and Aβ. First, due to the K16N mutation APP secretion is affected and a higher amount of Aβ peptides is being produced. Second, Aβ peptides carrying the K16N mutation are unique in that the peptide itself is not harmful to neuronal cells. Severe toxicity, however, is evident upon equimolar mixture of wt and mutant peptides, mimicking the heterozygous state of the subject. Furthermore, Aβ42 K16N inhibits fibril formation of Aβ42 wild-type. Even more, Aβ42 K16N peptides are protected against clearance activity by the major Aβ-degrading enzyme neprilysin. Thus the mutation characterized here harbours a combination of risk factors that synergistically may contribute to the development of early onset Alzheimer disease.
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Affiliation(s)
- Daniela Kaden
- Institut fuer Chemie und Biochemie, Freie Universitaet, Berlin, Germany
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