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Ozsan McMillan I, Li JP, Wang L. Heparan sulfate proteoglycan in Alzheimer's disease: aberrant expression and functions in molecular pathways related to amyloid-β metabolism. Am J Physiol Cell Physiol 2023; 324:C893-C909. [PMID: 36878848 PMCID: PMC10069967 DOI: 10.1152/ajpcell.00247.2022] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2022] [Revised: 02/28/2023] [Accepted: 02/28/2023] [Indexed: 03/08/2023]
Abstract
Alzheimer's disease (AD) is the most common form of dementia. Currently, there is no effective treatment for AD, as its etiology remains poorly understood. Mounting evidence suggests that the accumulation and aggregation of amyloid-β peptides (Aβ), which constitute amyloid plaques in the brain, is critical for initiating and accelerating AD pathogenesis. Considerable efforts have been dedicated to shedding light on the molecular basis and fundamental origins of the impaired Aβ metabolism in AD. Heparan sulfate (HS), a linear polysaccharide of the glycosaminoglycan family, co-deposits with Aβ in plaques in the AD brain, directly binds and accelerates Aβ aggregation, and mediates Aβ internalization and cytotoxicity. Mouse model studies demonstrate that HS regulates Aβ clearance and neuroinflammation in vivo. Previous reviews have extensively explored these discoveries. Here, this review focuses on the recent advancements in understanding abnormal HS expression in the AD brain, the structural aspects of HS-Aβ interaction, and the molecules involved in modulating Aβ metabolism through HS interaction. Furthermore, this review presents a perspective on the potential effects of abnormal HS expression on Aβ metabolism and AD pathogenesis. In addition, the review highlights the importance of conducting further research to differentiate the spatiotemporal components of HS structure and function in the brain and AD pathogenesis.
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Affiliation(s)
- Ilayda Ozsan McMillan
- Department of Molecular Pharmacology & Physiology, Morsani College of Medicine, University of South Florida, Tampa, Florida, United States
- Byrd Alzheimer's Research Institute, Morsani College of Medicine, University of South Florida, Tampa, Florida, United States
| | - Jin-Ping Li
- Department of Medical Biochemistry and Microbiology & The Biomedical Center, University of Uppsala, Uppsala, Sweden
- SciLifeLab Uppsala, University of Uppsala, Uppsala, Sweden
| | - Lianchun Wang
- Department of Molecular Pharmacology & Physiology, Morsani College of Medicine, University of South Florida, Tampa, Florida, United States
- Byrd Alzheimer's Research Institute, Morsani College of Medicine, University of South Florida, Tampa, Florida, United States
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2
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Hogwood J, Mulloy B, Lever R, Gray E, Page CP. Pharmacology of Heparin and Related Drugs: An Update. Pharmacol Rev 2023; 75:328-379. [PMID: 36792365 DOI: 10.1124/pharmrev.122.000684] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2022] [Revised: 11/04/2022] [Accepted: 11/08/2022] [Indexed: 02/17/2023] Open
Abstract
Heparin has been used extensively as an antithrombotic and anticoagulant for close to 100 years. This anticoagulant activity is attributed mainly to the pentasaccharide sequence, which potentiates the inhibitory action of antithrombin, a major inhibitor of the coagulation cascade. More recently it has been elucidated that heparin exhibits anti-inflammatory effect via interference of the formation of neutrophil extracellular traps and this may also contribute to heparin's antithrombotic activity. This illustrates that heparin interacts with a broad range of biomolecules, exerting both anticoagulant and nonanticoagulant actions. Since our previous review, there has been an increased interest in these nonanticoagulant effects of heparin, with the beneficial role in patients infected with SARS2-coronavirus a highly topical example. This article provides an update on our previous review with more recent developments and observations made for these novel uses of heparin and an overview of the development status of heparin-based drugs. SIGNIFICANCE STATEMENT: This state-of-the-art review covers recent developments in the use of heparin and heparin-like materials as anticoagulant, now including immunothrombosis observations, and as nonanticoagulant including a role in the treatment of SARS-coronavirus and inflammatory conditions.
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Affiliation(s)
- John Hogwood
- Sackler Institute of Pulmonary Pharmacology, Institute of Pharmaceutical Science, King's College London, London, United Kingdom (B.M., E.G., C.P.P.); National Institute for Biological Standards and Control, South Mimms, Hertfordshire, United Kingdom (J.H., E.G.) and School of Pharmacy, University College London, London, United Kingdom (R.L.)
| | - Barbara Mulloy
- Sackler Institute of Pulmonary Pharmacology, Institute of Pharmaceutical Science, King's College London, London, United Kingdom (B.M., E.G., C.P.P.); National Institute for Biological Standards and Control, South Mimms, Hertfordshire, United Kingdom (J.H., E.G.) and School of Pharmacy, University College London, London, United Kingdom (R.L.)
| | - Rebeca Lever
- Sackler Institute of Pulmonary Pharmacology, Institute of Pharmaceutical Science, King's College London, London, United Kingdom (B.M., E.G., C.P.P.); National Institute for Biological Standards and Control, South Mimms, Hertfordshire, United Kingdom (J.H., E.G.) and School of Pharmacy, University College London, London, United Kingdom (R.L.)
| | - Elaine Gray
- Sackler Institute of Pulmonary Pharmacology, Institute of Pharmaceutical Science, King's College London, London, United Kingdom (B.M., E.G., C.P.P.); National Institute for Biological Standards and Control, South Mimms, Hertfordshire, United Kingdom (J.H., E.G.) and School of Pharmacy, University College London, London, United Kingdom (R.L.)
| | - Clive P Page
- Sackler Institute of Pulmonary Pharmacology, Institute of Pharmaceutical Science, King's College London, London, United Kingdom (B.M., E.G., C.P.P.); National Institute for Biological Standards and Control, South Mimms, Hertfordshire, United Kingdom (J.H., E.G.) and School of Pharmacy, University College London, London, United Kingdom (R.L.)
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3
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Wu L, Jiang W, Zhao N, Wang F. Heparan sulfate from porcine mucosa promotes amyloid-beta clearance in APP/PS1 mice and alleviates Alzheimer's pathology. Carbohydr Polym 2022; 285:119205. [DOI: 10.1016/j.carbpol.2022.119205] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Revised: 01/17/2022] [Accepted: 01/28/2022] [Indexed: 12/11/2022]
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4
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Morfino P, Aimo A, Panichella G, Rapezzi C, Emdin M. Amyloid seeding as a disease mechanism and treatment target in transthyretin cardiac amyloidosis. Heart Fail Rev 2022; 27:2187-2200. [PMID: 35386059 PMCID: PMC9546974 DOI: 10.1007/s10741-022-10237-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 03/26/2022] [Indexed: 11/25/2022]
Abstract
Transthyretin (TTR) is a tetrameric transport protein mainly synthesized by the liver and choroid plexus. ATTR amyloidosis is characterized by the misfolding of TTR monomers and their accumulation within tissues as amyloid fibres. Current therapeutic options rely on the blockade of TTR production, TTR stabilization to maintain the native structure of TTR, amyloid degradation, or induction of amyloid removal from tissues. “Amyloid seeds” are defined as small fibril fragments that induce amyloid precursors to assume a structure rich in β-sheets, thus promoting fibrillogenesis. Amyloid seeds are important to promote the amplification and spread of amyloid deposits. Further studies are needed to better understand the molecular structure of ATTR seeds (i.e. the characteristics of the most amyloidogenic species), and the conditions that promote the formation and multiplication of seeds in vivo. The pathological cascade may begin months to years before symptom onset, suggesting that seeds in tissues might potentially be used as biomarkers for the early disease stages. Inhibition of amyloid aggregation by anti-seeding peptides may represent a disease mechanism and treatment target in ATTR amyloidosis, with an additional benefit over current therapies.
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Affiliation(s)
- Paolo Morfino
- Institute of Life Sciences, Scuola Superiore Sant Anna, Piazza Martiri della Libertà 33, 56124, Pisa, Italy
| | - Alberto Aimo
- Institute of Life Sciences, Scuola Superiore Sant Anna, Piazza Martiri della Libertà 33, 56124, Pisa, Italy.
- Cardiology Division, Fondazione Toscana Gabriele Monasterio, Pisa, Italy.
| | - Giorgia Panichella
- Institute of Life Sciences, Scuola Superiore Sant Anna, Piazza Martiri della Libertà 33, 56124, Pisa, Italy
| | - Claudio Rapezzi
- Cardiologic Centre, University of Ferrara, Ferrara, Italy
- Maria Cecilia Hospital, GVM Care & Research, Cotignola (Ravenna), Ravenna, Italy
| | - Michele Emdin
- Institute of Life Sciences, Scuola Superiore Sant Anna, Piazza Martiri della Libertà 33, 56124, Pisa, Italy
- Cardiology Division, Fondazione Toscana Gabriele Monasterio, Pisa, Italy
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5
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Lewkowicz E, Jayaraman S, Gursky O. Protein Amyloid Cofactors: Charged Side-Chain Arrays Meet Their Match? Trends Biochem Sci 2021; 46:626-629. [PMID: 34210544 DOI: 10.1016/j.tibs.2021.05.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Revised: 05/05/2021] [Accepted: 05/08/2021] [Indexed: 12/25/2022]
Abstract
Recent advances in high-resolution structural studies of protein amyloids have revealed parallel in-register cross-β-sheets with periodic arrays of closely spaced identical residues. What do these structures tell us about the mechanisms of action of common amyloid-promoting factors, such as heparan sulfate (HS), nucleic acids, polyphosphates, anionic phospholipids, and acidic pH?
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Affiliation(s)
- Emily Lewkowicz
- Department of Physiology and Biophysics, Boston University School of Medicine, Boston, MA 02118, USA
| | - Shobini Jayaraman
- Department of Physiology and Biophysics, Boston University School of Medicine, Boston, MA 02118, USA
| | - Olga Gursky
- Department of Physiology and Biophysics, Boston University School of Medicine, Boston, MA 02118, USA.
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6
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Jin W, Zhang F, Linhardt RJ. Glycosaminoglycans in Neurodegenerative Diseases. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2021; 1325:189-204. [PMID: 34495536 DOI: 10.1007/978-3-030-70115-4_9] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Glycosaminoglycans (GAGs) are linear polysaccharides that consist of alternating disaccharides sequences of uronic acids and/or galactose hexamino sugars most of which are sulfated. GAGs are ubiquitously expressed on the cell surface, in the intracellular milieu and in the extracellular matrix of all animal cells. Thus, GAGs exhibit many essential roles in a variety of physiological and pathological processes. The targets of GAGs are GAG-binding proteins and related proteins that are of significant interest to both the academic community and in the pharmaceutical industry. In this review, the structures of GAGs, their binding proteins, and analogs are presented that further the development of GAGs and their analogs for the treatment of neurodegenerative diseases agents.
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Affiliation(s)
- Weihua Jin
- College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou, China.,Department of Chemical and Biological Engineering, Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, NY, USA
| | - Fuming Zhang
- Department of Chemical and Biological Engineering, Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, NY, USA.
| | - Robert J Linhardt
- Department of Chemical and Biological Engineering, Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, NY, USA. .,Department of Biological Science, Departments of Chemistry and Chemical Biology and Biomedical Engineering, Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, NY, USA.
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7
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Townsend D, Fullwood NJ, Yates EA, Middleton DA. Aggregation Kinetics and Filament Structure of a Tau Fragment Are Influenced by the Sulfation Pattern of the Cofactor Heparin. Biochemistry 2020; 59:4003-4014. [PMID: 32954725 PMCID: PMC7584336 DOI: 10.1021/acs.biochem.0c00443] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Revised: 09/11/2020] [Indexed: 01/16/2023]
Abstract
A pathological signature of Alzheimer's disease (AD) is the formation of neurofibrillary tangles comprising filamentous aggregates of the microtubule associated protein tau. Tau self-assembly is accelerated by polyanions including heparin, an analogue of heparan sulfate. Tau filaments colocalize with heparan sulfate proteoglycans (HSPGs) in vivo, and HSPGs may also assist the transcellular propagation of tau aggregates. Here, we investigate the role of the sulfate moieties of heparin in the aggregation of a recombinant tau fragment Δtau187, comprising residues 255-441 of the C-terminal microtubule-binding domain. The effects that the selective removal of the N-, 2-O-, and 6-O-sulfate groups from heparin have on the kinetics of tau aggregation, aggregate morphology, and protein structure and dynamics were examined. Aggregation kinetics monitored by thioflavin T (ThT) fluorescence revealed that aggregation is considerably slower in the presence of 2-O-desulfated heparin than with N- or 6-O-desulfated heparin. Transmission electron microscopy revealed that tau filaments induced by 2-O-desulfated heparin were more slender than filaments formed in the presence of intact heparin or 6-O-desulfated heparin. The 2-O-desulfated heparin-induced filaments had more extensive regions of flexibility than the other filaments, according to circular dichroism and solid-state NMR spectroscopy. These results indicate that the sulfation pattern of heparin regulates tau aggregation, not purely though electrostatic forces but also through conformational perturbations of heparin when the 2-O-sulfate is removed. These findings may have implications for the progression of AD, as the sulfation pattern of GAGs is known to change during the aging process, which is the main risk factor for the disease.
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Affiliation(s)
- David Townsend
- Department
of Chemistry, University of Lancaster, Lancaster LA1 4YB, U.K.
| | - Nigel J. Fullwood
- Division
of Biomedical and Life Sciences, University
of Lancaster, Lancaster LA1 4YG, U.K.
| | - Edwin A. Yates
- Department
of Biochemistry and Systems Biology, Institute of Systems, Molecular
and Integrative Biology, University of Liverpool, Liverpool L69 7ZB, U.K.
| | - David A. Middleton
- Department
of Chemistry, University of Lancaster, Lancaster LA1 4YB, U.K.
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8
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Townsend DJ, Middleton DA, Ashton L. Raman Spectroscopy with 2D Perturbation Correlation Moving Windows for the Characterization of Heparin-Amyloid Interactions. Anal Chem 2020; 92:13822-13828. [PMID: 32935978 DOI: 10.1021/acs.analchem.0c02390] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
It has been shown extensively that glycosaminoglycan (GAG)-protein interactions can induce, accelerate, and impede the clearance of amyloid fibrils associated with systemic and localized amyloidosis. Obtaining molecular details of these interactions is fundamental to our understanding of amyloid disease. Consequently, there is a need for analytical approaches that can identify protein conformational transitions and simultaneously characterize heparin interactions. By combining Raman spectroscopy with two-dimensional (2D) perturbation correlation moving window (2DPCMW) analysis, we have successfully identified changes in protein secondary structure during pH- and heparin-induced fibril formation of apolipoprotein A-I (apoA-I) associated with atherosclerosis. Furthermore, from the 2DPCMW, we have identified peak shifts and intensity variations in Raman peaks arising from different heparan sulfate moieties, indicating that protein-heparin interactions vary at different heparin concentrations. Raman spectroscopy thus reveals new mechanistic insights into the role of GAGs during amyloid fibril formation.
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Affiliation(s)
- David J Townsend
- Department of Chemistry, Lancaster University, Lancaster LA1 4YB, United Kingdom
| | - David A Middleton
- Department of Chemistry, Lancaster University, Lancaster LA1 4YB, United Kingdom
| | - Lorna Ashton
- Department of Chemistry, Lancaster University, Lancaster LA1 4YB, United Kingdom
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9
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Gallardo R, Ranson NA, Radford SE. Amyloid structures: much more than just a cross-β fold. Curr Opin Struct Biol 2020; 60:7-16. [PMID: 31683043 DOI: 10.1016/j.sbi.2019.09.001] [Citation(s) in RCA: 126] [Impact Index Per Article: 31.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2019] [Accepted: 09/04/2019] [Indexed: 01/10/2023]
Abstract
In recent years our understanding of amyloid structure has been revolutionised by innovations in cryo-electron microscopy, electron diffraction and solid-state NMR. These techniques have yielded high-resolution structures of fibrils isolated from patients with neurodegenerative disease, as well as those formed from amyloidogenic proteins in vitro. The results not only show the expected cross-β amyloid structure, but also reveal that the amyloid fold is unexpectedly diverse and complex. Here, we discuss this diversity, highlighting dynamic regions, ligand binding motifs, cavities, non-protein components, and structural polymorphism. Collectively, these variations combine to allow the generic amyloid fold to be realised in three dimensions in different ways, and this diversity may be related to the roles of fibrils in disease.
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Affiliation(s)
- Rodrigo Gallardo
- Astbury Centre for Structural Molecular Biology, School of Molecular and Cellular Biology, University of Leeds, Leeds, LS2 9JT, UK
| | - Neil A Ranson
- Astbury Centre for Structural Molecular Biology, School of Molecular and Cellular Biology, University of Leeds, Leeds, LS2 9JT, UK.
| | - Sheena E Radford
- Astbury Centre for Structural Molecular Biology, School of Molecular and Cellular Biology, University of Leeds, Leeds, LS2 9JT, UK.
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10
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Iadanza MG, Jackson MP, Hewitt EW, Ranson NA, Radford SE. A new era for understanding amyloid structures and disease. Nat Rev Mol Cell Biol 2019; 19:755-773. [PMID: 30237470 DOI: 10.1038/s41580-018-0060-8] [Citation(s) in RCA: 526] [Impact Index Per Article: 105.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The aggregation of proteins into amyloid fibrils and their deposition into plaques and intracellular inclusions is the hallmark of amyloid disease. The accumulation and deposition of amyloid fibrils, collectively known as amyloidosis, is associated with many pathological conditions that can be associated with ageing, such as Alzheimer disease, Parkinson disease, type II diabetes and dialysis-related amyloidosis. However, elucidation of the atomic structure of amyloid fibrils formed from their intact protein precursors and how fibril formation relates to disease has remained elusive. Recent advances in structural biology techniques, including cryo-electron microscopy and solid-state NMR spectroscopy, have finally broken this impasse. The first near-atomic-resolution structures of amyloid fibrils formed in vitro, seeded from plaque material and analysed directly ex vivo are now available. The results reveal cross-β structures that are far more intricate than anticipated. Here, we describe these structures, highlighting their similarities and differences, and the basis for their toxicity. We discuss how amyloid structure may affect the ability of fibrils to spread to different sites in the cell and between organisms in a prion-like manner, along with their roles in disease. These molecular insights will aid in understanding the development and spread of amyloid diseases and are inspiring new strategies for therapeutic intervention.
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Affiliation(s)
- Matthew G Iadanza
- Astbury Centre for Structural Molecular Biology, School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, UK
| | - Matthew P Jackson
- Astbury Centre for Structural Molecular Biology, School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, UK
| | - Eric W Hewitt
- Astbury Centre for Structural Molecular Biology, School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, UK
| | - Neil A Ranson
- Astbury Centre for Structural Molecular Biology, School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, UK
| | - Sheena E Radford
- Astbury Centre for Structural Molecular Biology, School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, UK.
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11
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Benseny-Cases N, Karamanos TK, Hoop CL, Baum J, Radford SE. Extracellular matrix components modulate different stages in β 2-microglobulin amyloid formation. J Biol Chem 2019; 294:9392-9401. [PMID: 30996004 PMCID: PMC6579475 DOI: 10.1074/jbc.ra119.008300] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2019] [Revised: 04/09/2019] [Indexed: 11/26/2022] Open
Abstract
Amyloid deposition of WT human β2-microglobulin (WT-hβ2m) in the joints of long-term hemodialysis patients is the hallmark of dialysis-related amyloidosis. In vitro, WT-hβ2m does not form amyloid fibrils at physiological pH and temperature unless co-solvents or other reagents are added. Therefore, understanding how fibril formation is initiated and maintained in the joint space is important for elucidating WT-hβ2m aggregation and dialysis-related amyloidosis onset. Here, we investigated the roles of collagen I and the commonly administered anticoagulant, low-molecular-weight (LMW) heparin, in the initiation and subsequent aggregation phases of WT-hβ2m in physiologically relevant conditions. Using thioflavin T fluorescence to study the kinetics of amyloid formation, we analyzed how these two agents affect specific stages of WT-hβ2m assembly. Our results revealed that LMW-heparin strongly promotes WT-hβ2m fibrillogenesis during all stages of aggregation. However, collagen I affected WT-hβ2m amyloid formation in contrasting ways: decreasing the lag time of fibril formation in the presence of LMW-heparin and slowing the rate at higher concentrations. We found that in self-seeded reactions, interaction of collagen I with WT-hβ2m amyloid fibrils attenuates surface-mediated growth of WT-hβ2m fibrils, demonstrating a key role of secondary nucleation in WT-hβ2m amyloid formation. Interestingly, collagen I fibrils did not suppress surface-mediated assembly of WT-hβ2m monomers when cross-seeded with fibrils formed from the N-terminally truncated variant ΔN6-hβ2m. Together, these results provide detailed insights into how collagen I and LMW-heparin impact different stages in the aggregation of WT-hβ2m into amyloid, which lead to dramatic effects on the time course of assembly.
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Affiliation(s)
- Núria Benseny-Cases
- From the Astbury Centre for Structural Molecular Biology and School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, United Kingdom and
| | - Theodoros K Karamanos
- From the Astbury Centre for Structural Molecular Biology and School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, United Kingdom and
| | - Cody L Hoop
- the Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, New Jersey 08854
| | - Jean Baum
- the Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, New Jersey 08854
| | - Sheena E Radford
- From the Astbury Centre for Structural Molecular Biology and School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, United Kingdom and
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12
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Bunce SJ, Wang Y, Stewart KL, Ashcroft AE, Radford SE, Hall CK, Wilson AJ. Molecular insights into the surface-catalyzed secondary nucleation of amyloid-β 40 (Aβ 40) by the peptide fragment Aβ 16-22. SCIENCE ADVANCES 2019; 5:eaav8216. [PMID: 31245536 PMCID: PMC6588359 DOI: 10.1126/sciadv.aav8216] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2018] [Accepted: 05/15/2019] [Indexed: 05/15/2023]
Abstract
Understanding the structural mechanism by which proteins and peptides aggregate is crucial, given the role of fibrillar aggregates in debilitating amyloid diseases and bioinspired materials. Yet, this is a major challenge as the assembly involves multiple heterogeneous and transient intermediates. Here, we analyze the co-aggregation of Aβ40 and Aβ16-22, two widely studied peptide fragments of Aβ42 implicated in Alzheimer's disease. We demonstrate that Aβ16-22 increases the aggregation rate of Aβ40 through a surface-catalyzed secondary nucleation mechanism. Discontinuous molecular dynamics simulations allowed aggregation to be tracked from the initial random coil monomer to the catalysis of nucleation on the fibril surface. Together, the results provide insight into how dynamic interactions between Aβ40 monomers/oligomers on the surface of preformed Aβ16-22 fibrils nucleate Aβ40 amyloid assembly. This new understanding may facilitate development of surfaces designed to enhance or suppress secondary nucleation and hence to control the rates and products of fibril assembly.
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Affiliation(s)
- Samuel J. Bunce
- School of Chemistry, University of Leeds, Leeds LS2 9JT, UK
- Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds LS2 9JT, UK
| | - Yiming Wang
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC 27695-7905, USA
| | - Katie L. Stewart
- Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds LS2 9JT, UK
- School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, UK
| | - Alison E. Ashcroft
- Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds LS2 9JT, UK
- School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, UK
| | - Sheena E. Radford
- Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds LS2 9JT, UK
- School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, UK
- Corresponding author. (S.E.R.); (C.K.H.); (A.J.W.)
| | - Carol K. Hall
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC 27695-7905, USA
- Corresponding author. (S.E.R.); (C.K.H.); (A.J.W.)
| | - Andrew J. Wilson
- School of Chemistry, University of Leeds, Leeds LS2 9JT, UK
- Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds LS2 9JT, UK
- Corresponding author. (S.E.R.); (C.K.H.); (A.J.W.)
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13
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A Glycosaminoglycan Extract from Portunus pelagicus Inhibits BACE1, the β Secretase Implicated in Alzheimer's Disease. Mar Drugs 2019; 17:md17050293. [PMID: 31100859 PMCID: PMC6562973 DOI: 10.3390/md17050293] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2019] [Revised: 05/08/2019] [Accepted: 05/09/2019] [Indexed: 12/23/2022] Open
Abstract
Therapeutic options for Alzheimer’s disease, the most common form of dementia, are currently restricted to palliative treatments. The glycosaminoglycan heparin, widely used as a clinical anticoagulant, has previously been shown to inhibit the Alzheimer’s disease-relevant β-secretase 1 (BACE1). Despite this, the deployment of pharmaceutical heparin for the treatment of Alzheimer’s disease is largely precluded by its potent anticoagulant activity. Furthermore, ongoing concerns regarding the use of mammalian-sourced heparins, primarily due to prion diseases and religious beliefs hinder the deployment of alternative heparin-based therapeutics. A marine-derived, heparan sulphate-containing glycosaminoglycan extract, isolated from the crab Portunus pelagicus, was identified to inhibit human BACE1 with comparable bioactivity to that of mammalian heparin (IC50 = 1.85 μg mL−1 (R2 = 0.94) and 2.43 μg mL−1 (R2 = 0.93), respectively), while possessing highly attenuated anticoagulant activities. The results from several structural techniques suggest that the interactions between BACE1 and the extract from P. pelagicus are complex and distinct from those of heparin.
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14
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Shen K, Gamerdinger M, Chan R, Gense K, Martin EM, Sachs N, Knight PD, Schlömer R, Calabrese AN, Stewart KL, Leiendecker L, Baghel A, Radford SE, Frydman J, Deuerling E. Dual Role of Ribosome-Binding Domain of NAC as a Potent Suppressor of Protein Aggregation and Aging-Related Proteinopathies. Mol Cell 2019; 74:729-741.e7. [PMID: 30982745 PMCID: PMC6527867 DOI: 10.1016/j.molcel.2019.03.012] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2018] [Revised: 01/22/2019] [Accepted: 03/08/2019] [Indexed: 01/11/2023]
Abstract
The nascent polypeptide-associated complex (NAC) is a conserved ribosome-associated protein biogenesis factor. Whether NAC exerts chaperone activity and whether this function is restricted to de novo protein synthesis is unknown. Here, we demonstrate that NAC directly exerts chaperone activity toward structurally diverse model substrates including polyglutamine (PolyQ) proteins, firefly luciferase, and Aβ40. Strikingly, we identified the positively charged ribosome-binding domain in the N terminus of the βNAC subunit (N-βNAC) as a major chaperone entity of NAC. N-βNAC by itself suppressed aggregation of PolyQ-expanded proteins in vitro, and the positive charge of this domain was critical for this activity. Moreover, we found that NAC also exerts a ribosome-independent chaperone function in vivo. Consistently, we found that a substantial fraction of NAC is non-ribosomal bound in higher eukaryotes. In sum, NAC is a potent suppressor of aggregation and proteotoxicity of mutant PolyQ-expanded proteins associated with human diseases like Huntington's disease and spinocerebellar ataxias.
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Affiliation(s)
- Koning Shen
- Department of Biology, Stanford University, Stanford, CA 94305-5430, USA
| | | | - Rebecca Chan
- Department of Biology, Stanford University, Stanford, CA 94305-5430, USA
| | - Karina Gense
- Department of Biology, University of Konstanz, 78457 Konstanz, Germany
| | - Esther M Martin
- Astbury Centre for Structural Molecular Biology, School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, UK
| | - Nadine Sachs
- Department of Biology, University of Konstanz, 78457 Konstanz, Germany
| | - Patrick D Knight
- Astbury Centre for Structural Molecular Biology, School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, UK
| | - Renate Schlömer
- Department of Biology, University of Konstanz, 78457 Konstanz, Germany
| | - Antonio N Calabrese
- Astbury Centre for Structural Molecular Biology, School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, UK
| | - Katie L Stewart
- Astbury Centre for Structural Molecular Biology, School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, UK
| | - Lukas Leiendecker
- Department of Biology, University of Konstanz, 78457 Konstanz, Germany
| | - Ankit Baghel
- Department of Biology, Stanford University, Stanford, CA 94305-5430, USA
| | - Sheena E Radford
- Astbury Centre for Structural Molecular Biology, School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, UK.
| | - Judith Frydman
- Department of Biology, Stanford University, Stanford, CA 94305-5430, USA.
| | - Elke Deuerling
- Department of Biology, University of Konstanz, 78457 Konstanz, Germany.
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15
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Sebastiao M, Quittot N, Marcotte I, Bourgault S. Glycosaminoglycans Induce Amyloid Self-Assembly of a Peptide Hormone by Concerted Secondary and Quaternary Conformational Transitions. Biochemistry 2019; 58:1214-1225. [PMID: 30720275 DOI: 10.1021/acs.biochem.8b01206] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Amyloids are polypeptide supramolecular assemblies that have been historically associated with numerous pathologies. Nonetheless, recent studies have identified many amyloid structures that accomplish vital physiological functions. Interestingly, amyloid fibrils, either pathological or functional, have been reported to be consistently associated with other biomolecules such as RNA and glycosaminoglycans (GAGs). These linear polyanions, RNA and GAGs, have also demonstrated an inherent ability to accelerate and/or promote amyloid formation. GAGs, including heparan sulfate, are highly charged polysaccharides that may have essential roles in the storage of peptide hormones in the form of amyloids. In this study, we evaluated the ability of sulfated GAGs to promote the self-assembly of the peptide (neuro)hormone PACAP27 and investigated the secondary and quaternary conformational transitions associated with the amyloidogenic process. PACAP27 readily self-assembled into insoluble, α-helix-rich globular particulates in the presence of sulfated GAGs, which gradually condensed and disappeared as nontoxic β-sheet-rich amyloid fibrils were formed. By designing a PACAP27 derivative for which helical folding was hindered, we observed that the α-helix-to-β-sheet conformational transition within the amorphous particulates constitutes the rate-limiting step of primary nucleation events. The proposed mechanism of GAG-induced self-assembly within insoluble particulates appears to be fundamentally different from usual amyloidogenic systems, which commonly implicates the formation of soluble prefibrillar proteospecies. Overall, this study provides new insights into the mechanistic details involved in the formation of functional amyloids catalyzed by polyanions, such as the assembly of nuclear amyloid bodies and the storage of peptide hormones.
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Affiliation(s)
- Mathew Sebastiao
- Department of Chemistry , Université du Québec à Montréal , C.P. 8888, Succursale Centre-Ville , Montreal H3C 3P8 , Canada.,Quebec Network for Research on Protein Function, Engineering and Applications, PROTEO , Université Laval , Québec G1V 0A6 , Canada
| | - Noe Quittot
- Department of Chemistry , Université du Québec à Montréal , C.P. 8888, Succursale Centre-Ville , Montreal H3C 3P8 , Canada.,Quebec Network for Research on Protein Function, Engineering and Applications, PROTEO , Université Laval , Québec G1V 0A6 , Canada
| | - Isabelle Marcotte
- Department of Chemistry , Université du Québec à Montréal , C.P. 8888, Succursale Centre-Ville , Montreal H3C 3P8 , Canada.,Quebec Network for Research on Protein Function, Engineering and Applications, PROTEO , Université Laval , Québec G1V 0A6 , Canada
| | - Steve Bourgault
- Department of Chemistry , Université du Québec à Montréal , C.P. 8888, Succursale Centre-Ville , Montreal H3C 3P8 , Canada.,Quebec Network for Research on Protein Function, Engineering and Applications, PROTEO , Université Laval , Québec G1V 0A6 , Canada
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16
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Zinc binding regulates amyloid-like aggregation of GAPR-1. Biosci Rep 2019; 39:BSR20182345. [PMID: 30700571 PMCID: PMC6900432 DOI: 10.1042/bsr20182345] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2018] [Revised: 01/23/2019] [Accepted: 01/29/2019] [Indexed: 12/11/2022] Open
Abstract
Members of the CAP superfamily (Cysteine-rich secretory proteins, Antigen 5, and Pathogenesis-related 1 proteins) are characterized by the presence of a CAP domain that is defined by four sequence motifs and a highly conserved tertiary structure. A common structure–function relationship for this domain is hitherto unknown. A characteristic of several CAP proteins is their formation of amyloid-like structures in the presence of lipids. Here we investigate the structural modulation of Golgi-Associated plant Pathogenesis Related protein 1 (GAPR-1) by known interactors of the CAP domain, preceding amyloid-like aggregation. Using isothermal titration calorimetry (ITC), we demonstrate that GAPR-1 binds zinc ions. Zn2+ binding causes a slight but significant conformational change as revealed by CD, tryptophan fluorescence, and trypsin digestion. The Zn2+-induced conformational change was required for the formation of GAPR-1 oligomers and amyloid-like assemblies in the presence of heparin, as shown by ThT fluorescence and TEM. Molecular dynamics simulations show binding of Zn2+ to His54 and His103. Mutation of these two highly conserved residues resulted in strongly diminished amyloid-like aggregation. Finally, we show that proteins from the cysteine-rich secretory protein (CRISP) subfamily are also able to form ThT-positive structures in vitro in a heparin- and Zn2+-dependent manner, suggesting that oligomerization regulated by metal ions could be a common structural property of the CAP domain.
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17
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Townsend D, Hughes E, Stewart KL, Griffin JM, Radford SE, Middleton DA. Orientation of a Diagnostic Ligand Bound to Macroscopically Aligned Amyloid-β Fibrils Determined by Solid-State NMR. J Phys Chem Lett 2018; 9:6611-6615. [PMID: 30354142 DOI: 10.1021/acs.jpclett.8b02448] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
With amyloid diseases poised to become a major health burden in countries with aging populations, diagnostic molecules that aid the detection of amyloid in vitro and in vivo are of considerable clinical value. Understanding how such ligands recognize their amyloid targets would help to design diagnostics that target specific amyloid types associated with a particular disease, but methods to provide comprehensive information are underdeveloped. Here, solid-state NMR is used to determine the molecular orientation of the amyloid diagnostic 1-fluoro-2,5-bis[( E)-3-carboxy-4-hydroxystyryl]-benzene (FSB) when bound to fibrils of the Alzheimer's amyloid-β polypeptide aligned on a planar substrate. The 19F NMR spectrum of the aligned complex reveals that FSB is oriented approximately parallel with the fibril long axis and bridges four hydrogen-bonded β-sheets. In addition to providing atomic details to aid the design of amyloid-specific diagnostics, this approach will also illuminate the molecular mechanisms of accessory molecules in amyloid disease.
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Affiliation(s)
- David Townsend
- Department of Chemistry , Lancaster University , Lancaster LA1 4YB , United Kingdom
| | - Eleri Hughes
- Department of Chemistry , Lancaster University , Lancaster LA1 4YB , United Kingdom
| | - Katie L Stewart
- Department of Physics , Emory University , Atlanta , Georgia 30322 , United States
| | - John M Griffin
- Materials Science Institute , Lancaster University , Lancaster LA1 4YB , United Kingdom
| | - Sheena E Radford
- Astbury Centre for Structural Molecular Biology, School of Molecular and Cellular Biology , Faculty of Biological Sciences, University of Leeds , Leeds LS2 9JT , United Kingdom
| | - David A Middleton
- Department of Chemistry , Lancaster University , Lancaster LA1 4YB , United Kingdom
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18
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Zhang X, Fu Z, Meng L, He M, Zhang Z. The Early Events That Initiate β-Amyloid Aggregation in Alzheimer's Disease. Front Aging Neurosci 2018; 10:359. [PMID: 30542277 PMCID: PMC6277872 DOI: 10.3389/fnagi.2018.00359] [Citation(s) in RCA: 70] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2018] [Accepted: 10/22/2018] [Indexed: 12/18/2022] Open
Abstract
Alzheimer’s disease (AD) is characterized by the development of amyloid plaques and neurofibrillary tangles (NFTs) consisting of aggregated β-amyloid (Aβ) and tau, respectively. The amyloid hypothesis has been the predominant framework for research in AD for over two decades. According to this hypothesis, the accumulation of Aβ in the brain is the primary factor initiating the pathogenesis of AD. However, it remains elusive what factors initiate Aβ aggregation. Studies demonstrate that AD has multiple causes, including genetic and environmental factors. Furthermore, genetic factors, many age-related events and pathological conditions such as diabetes, traumatic brain injury (TBI) and aberrant microbiota also affect the aggregation of Aβ. Here we provide an overview of the age-related early events and other pathological processes that precede Aβ aggregation.
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Affiliation(s)
- Xingyu Zhang
- Department of Neurology, Renmin Hospital of Wuhan University, Wuhan, China
| | - Zhihui Fu
- Department of Neurology, Renmin Hospital of Wuhan University, Wuhan, China
| | - Lanxia Meng
- Department of Neurology, Renmin Hospital of Wuhan University, Wuhan, China
| | - Mingyang He
- Department of Neurology, Renmin Hospital of Wuhan University, Wuhan, China
| | - Zhentao Zhang
- Department of Neurology, Renmin Hospital of Wuhan University, Wuhan, China
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19
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Glycosaminoglycan-Protein Interactions by Nuclear Magnetic Resonance (NMR) Spectroscopy. Molecules 2018; 23:molecules23092314. [PMID: 30208595 PMCID: PMC6225283 DOI: 10.3390/molecules23092314] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2018] [Revised: 08/29/2018] [Accepted: 09/05/2018] [Indexed: 02/07/2023] Open
Abstract
Nuclear magnetic resonance (NMR) spectroscopy is one of the most utilized and informative analytical techniques for investigating glycosaminoglycan (GAG)-protein complexes. NMR methods that are commonly applied to GAG-protein systems include chemical shift perturbation, saturation transfer difference, and transferred nuclear Overhauser effect. Although these NMR methods have revealed valuable insight into the protein-GAG complexes, elucidating high-resolution structural and dynamic information of these often transient interactions remains challenging. In addition, preparation of structurally homogeneous and isotopically enriched GAG ligands for structural investigations continues to be laborious. As a result, understanding of the structure-activity relationship of GAGs is still primitive. To overcome these deficiencies, several innovative NMR techniques have been developed lately. Here, we review some of the commonly used techniques along with more novel methods such as waterLOGSY and experiments to examine structure and dynamic of lysine and arginine side chains to identify GAG-binding sites. We will also present the latest technology that is used to produce isotopically enriched as well as paramagnetically tagged GAG ligands. Recent results that were obtained from solid-state NMR of amyloid’s interaction with GAG are also presented together with a brief discussion on computer assisted modeling of GAG-protein complexes using sparse experimental data.
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20
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Kjellén L, Lindahl U. Specificity of glycosaminoglycan–protein interactions. Curr Opin Struct Biol 2018; 50:101-108. [DOI: 10.1016/j.sbi.2017.12.011] [Citation(s) in RCA: 77] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2017] [Revised: 12/15/2017] [Accepted: 12/22/2017] [Indexed: 12/21/2022]
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21
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Townsend D, Hughes E, Akien G, Stewart KL, Radford SE, Rochester D, Middleton DA. Epigallocatechin-3-gallate remodels apolipoprotein A-I amyloid fibrils into soluble oligomers in the presence of heparin. J Biol Chem 2018; 293:12877-12893. [PMID: 29853648 PMCID: PMC6102129 DOI: 10.1074/jbc.ra118.002038] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2018] [Revised: 05/25/2018] [Indexed: 11/06/2022] Open
Abstract
Amyloid deposits of WT apolipoprotein A-I (apoA-I), the main protein component of high-density lipoprotein, accumulate in atherosclerotic plaques where they may contribute to coronary artery disease by increasing plaque burden and instability. Using CD analysis, solid-state NMR spectroscopy, and transmission EM, we report here a surprising cooperative effect of heparin and the green tea polyphenol (-)-epigallocatechin-3-gallate (EGCG), a known inhibitor and modulator of amyloid formation, on apoA-I fibrils. We found that heparin, a proxy for glycosaminoglycan (GAG) polysaccharides that co-localize ubiquitously with amyloid in vivo, accelerates the rate of apoA-I formation from monomeric protein and associates with insoluble fibrils. Mature, insoluble apoA-I fibrils bound EGCG (KD = 30 ± 3 μm; Bmax = 40 ± 3 μm), but EGCG did not alter the kinetics of apoA-I amyloid assembly from monomer in the presence or absence of heparin. EGCG selectively increased the mobility of specific backbone and side-chain sites of apoA-I fibrils formed in the absence of heparin, but the fibrils largely retained their original morphology and remained insoluble. By contrast, fibrils formed in the presence of heparin were mobilized extensively by the addition of equimolar EGCG, and the fibrils were remodeled into soluble 20-nm-diameter oligomers with a largely α-helical structure that were nontoxic to human umbilical artery endothelial cells. These results argue for a protective effect of EGCG on apoA-I amyloid associated with atherosclerosis and suggest that EGCG-induced remodeling of amyloid may be tightly regulated by GAGs and other amyloid co-factors in vivo, depending on EGCG bioavailability.
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Affiliation(s)
- David Townsend
- Department of Chemistry, Lancaster University, Lancaster LA1 4YB
| | - Eleri Hughes
- Department of Chemistry, Lancaster University, Lancaster LA1 4YB
| | - Geoffrey Akien
- Department of Chemistry, Lancaster University, Lancaster LA1 4YB
| | - Katie L Stewart
- Astbury Centre for Structural Molecular Biology, School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Sheena E Radford
- Astbury Centre for Structural Molecular Biology, School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - David Rochester
- Department of Chemistry, Lancaster University, Lancaster LA1 4YB
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