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Gao LP, Chen HC, Ma ZL, Chen AD, Du HL, Yin J, Jing YH. Fibrillation of human islet amyloid polypeptide and its toxicity to pancreatic β-cells under lipid environment. Biochim Biophys Acta Gen Subj 2019; 1864:129422. [PMID: 31491457 DOI: 10.1016/j.bbagen.2019.129422] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2019] [Revised: 08/20/2019] [Accepted: 08/27/2019] [Indexed: 01/19/2023]
Abstract
BACKGROUND Previous studies suggested that fibrillar human IAPP (hIAPP) is more likely to deposit in β-cells, resulting in β-cell injury. However, the changes in the conformation of hIAPP in lipid environment and the mechanism involved in β-cell damage are unclear. METHODS Synthetic hIAPP was incubated with five types of free fatty acids and phospholipids 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) and 1-palmitoyl-2-oleoyl-sn-glycero-3-phospho-l-serine (POPS), which constitute the cell membrane. Thioflavin-T fluorescence assay was conducted to analyze the degree of hIAPP fibrosis, and circular dichroism spectroscopy was performed to detect the β-fold formation of hIAPP. Furthermore, INS-1 cells were infected with human IAPP delivered by a GV230-EGFP plasmid. The effects of endogenous hIAPP overexpression induced by sodium palmitate on the survival, endoplasmic reticulum (ER) stress, and apoptosis of INS-1 cells were evaluated. RESULTS The five types of free fatty acids can accelerate the fibrosis of hIAPP. Sodium palmitate also maintained the stability of fibrillar hIAPP. POPS, not POPC, accelerated hIAPP fibrosis. Treatment of INS-1 cells with sodium palmitate increased the expression of hIAPP, activated ER stress and ER stress-dependent apoptosis signaling pathways, and increased the apoptotic rate. CONCLUSION Free fatty acids and anionic phospholipid can promote β-fold formation and fibrosis in hIAPP. High lipid induced the overexpression of hIAPP and aggravated ER stress and apoptosis in INS-1 cells, which caused β-cell death in high lipid environment. GENERAL SIGNIFICANCE Our study reveals free fatty acids and hIAPP synergistically implicated in endoplasmic reticulum stress and apoptosis of islet β-cells.
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Affiliation(s)
- Li-Ping Gao
- Institute of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Lanzhou University, Lanzhou City, Gansu province 730000, People's Republic of China
| | - Hai-Chao Chen
- Institute of Anatomy and Histology & Embryology, Neuroscience, School of Basic Medical Sciences, Lanzhou University, Lanzhou City, Gansu Province 730000, People's Republic of China
| | - Ze-Lin Ma
- Institute of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Lanzhou University, Lanzhou City, Gansu province 730000, People's Republic of China
| | - An-Di Chen
- Institute of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Lanzhou University, Lanzhou City, Gansu province 730000, People's Republic of China
| | - Hong-Li Du
- Institute of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Lanzhou University, Lanzhou City, Gansu province 730000, People's Republic of China
| | - Jie Yin
- Institute of Anatomy and Histology & Embryology, Neuroscience, School of Basic Medical Sciences, Lanzhou University, Lanzhou City, Gansu Province 730000, People's Republic of China
| | - Yu-Hong Jing
- Institute of Anatomy and Histology & Embryology, Neuroscience, School of Basic Medical Sciences, Lanzhou University, Lanzhou City, Gansu Province 730000, People's Republic of China; Key Laboratory of Preclinical Study for New Drugs of Gansu province, Lanzhou University, Lanzhou City, Gansu Province 730000, People's Republic of China.
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De Maio A, Cauvi DM, Capone R, Bello I, Egberts WV, Arispe N, Boelens W. The small heat shock proteins, HSPB1 and HSPB5, interact differently with lipid membranes. Cell Stress Chaperones 2019; 24:947-956. [PMID: 31338686 PMCID: PMC6717221 DOI: 10.1007/s12192-019-01021-y] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2019] [Revised: 06/24/2019] [Accepted: 07/12/2019] [Indexed: 12/15/2022] Open
Abstract
Increasing evidence shows that heat shock proteins (hsp) escape the cytosol gaining access to the extracellular environment, acting as signaling agents. Since the majority of these proteins lack the information necessary for their export via the classical secretory pathway, attention has been focused on alternative releasing mechanisms. Crossing the plasma membrane is a major obstacle to the secretion of a cytosolic protein into the extracellular milieu. Several mechanisms have been proposed, including direct interaction with the plasma membrane or their release within extracellular vesicles (ECV). HSPB1 (Hsp27), which belongs to the small hsp family, was detected within the membrane of ECV released from stressed HepG2 cells. To further investigate this finding, we studied the interaction of HSPB1 with lipid membranes using liposomes. We found that HSPB1 interacted with liposomes made of palmitoyl oleoyl phosphatidylserine (POPS), palmitoyl oleoyl phosphatidylcholine (POPC), and palmitoyl oleoyl phosphatidylglycerol (POPG), with different characteristics. Another member of the small hsp family, HSPB5 (αB-crystallin), has also been detected within ECV released from HeLa cells transfected with this gene. This protein was found to interact with liposomes as well, but differently than HSPB1. To address the regions interacting with the membrane, proteoliposomes were digested with proteinase K and the protected domains within the liposomes were identified by mass spectroscopy. We observed that large parts of HSPB1 and HSPB5 were embedded within the liposomes, particularly the alpha-crystallin domain. These observations suggest that the interaction with lipid membranes may be part of the mechanisms of export of these proteins.
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Affiliation(s)
- Antonio De Maio
- Department of Surgery, Division of Trauma, Critical Care, Burns and Acute Care Surgery, School of Medicine, University of California San Diego, 9500 Gilman Drive, #0739, La Jolla, CA 92093-0739 USA
- Department of Neurosciences, Division of Trauma, Critical Care, Burns and Acute, School of Medicine, University of California San Diego, La Jolla, CA 92093 USA
| | - David M. Cauvi
- Department of Surgery, Division of Trauma, Critical Care, Burns and Acute Care Surgery, School of Medicine, University of California San Diego, 9500 Gilman Drive, #0739, La Jolla, CA 92093-0739 USA
| | - Ricardo Capone
- Department of Surgery, Division of Trauma, Critical Care, Burns and Acute Care Surgery, School of Medicine, University of California San Diego, 9500 Gilman Drive, #0739, La Jolla, CA 92093-0739 USA
| | - Ivan Bello
- Department of Surgery, Division of Trauma, Critical Care, Burns and Acute Care Surgery, School of Medicine, University of California San Diego, 9500 Gilman Drive, #0739, La Jolla, CA 92093-0739 USA
| | - Wilma Vree Egberts
- Department of Biomolecular Chemistry, Institute for Molecules and Materials and Radboud Institute for Molecular Life Sciences, Radboud University Nijmegen, P.O. Box 9101, 6500 HB Nijmegen, The Netherlands
| | - Nelson Arispe
- Department of Anatomy, Physiology and Genetics, School of Medicine, Uniformed Services University, Bethesda, MD 20814 USA
| | - Wilbert Boelens
- Department of Anatomy, Physiology and Genetics, School of Medicine, Uniformed Services University, Bethesda, MD 20814 USA
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Efimova SS, Ostroumova OS. Mechanisms of Regulation of Amyloid-Induced Permeability of Model Lipid Membranes by Polyphenols. ACTA ACUST UNITED AC 2019. [DOI: 10.1134/s1990519x19040023] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Siddiqi MK, Malik S, Majid N, Alam P, Khan RH. Cytotoxic species in amyloid-associated diseases: Oligomers or mature fibrils. ADVANCES IN PROTEIN CHEMISTRY AND STRUCTURAL BIOLOGY 2019; 118:333-369. [PMID: 31928731 DOI: 10.1016/bs.apcsb.2019.06.001] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Amyloid diseases especially, Alzheimer's disease (AD), is characterized by an imbalance between the production and clearance of amyloid-β (Aβ) species. Amyloidogenic proteins or peptides can transform structurally from monomers into β-stranded fibrils via multiple oligomeric states. Among various amyloid species, structured oligomers are proposed to be more toxic than fibrils; however, the identification of amyloid oligomers has been challenging due to their heterogeneous and metastable nature. Multiple techniques have recently helped in better understanding of oligomer's assembly details and structural properties. Moreover, some progress on elucidating the mechanisms of oligomer-triggered toxicity has been made. Based on the collection of current findings, there is growing consensus that control of toxic amyloid oligomers could be a valid approach to regulate amyloid-associated toxicity, which could advance development of new diagnostics and therapeutics for amyloid-related diseases. In this review, we have described the recent scenario of amyloid diseases with a great deal of information about the recent understanding of oligomers' assembly, structural properties, and toxicity. Also comprehensive details have been provided to differentiate the degree of toxicity associated with prefibrillar aggregates.
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Affiliation(s)
| | - Sadia Malik
- Interdisciplinary Biotechnology Unit, Aligarh Muslim University, Aligarh, India
| | - Nabeela Majid
- Interdisciplinary Biotechnology Unit, Aligarh Muslim University, Aligarh, India
| | - Parvez Alam
- Interdisciplinary Biotechnology Unit, Aligarh Muslim University, Aligarh, India
| | - Rizwan Hasan Khan
- Interdisciplinary Biotechnology Unit, Aligarh Muslim University, Aligarh, India
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Owen MC, Gnutt D, Gao M, Wärmländer SKTS, Jarvet J, Gräslund A, Winter R, Ebbinghaus S, Strodel B. Effects of in vivo conditions on amyloid aggregation. Chem Soc Rev 2019; 48:3946-3996. [PMID: 31192324 DOI: 10.1039/c8cs00034d] [Citation(s) in RCA: 123] [Impact Index Per Article: 24.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
One of the grand challenges of biophysical chemistry is to understand the principles that govern protein misfolding and aggregation, which is a highly complex process that is sensitive to initial conditions, operates on a huge range of length- and timescales, and has products that range from protein dimers to macroscopic amyloid fibrils. Aberrant aggregation is associated with more than 25 diseases, which include Alzheimer's, Parkinson's, Huntington's, and type II diabetes. Amyloid aggregation has been extensively studied in the test tube, therefore under conditions that are far from physiological relevance. Hence, there is dire need to extend these investigations to in vivo conditions where amyloid formation is affected by a myriad of biochemical interactions. As a hallmark of neurodegenerative diseases, these interactions need to be understood in detail to develop novel therapeutic interventions, as millions of people globally suffer from neurodegenerative disorders and type II diabetes. The aim of this review is to document the progress in the research on amyloid formation from a physicochemical perspective with a special focus on the physiological factors influencing the aggregation of the amyloid-β peptide, the islet amyloid polypeptide, α-synuclein, and the hungingtin protein.
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Affiliation(s)
- Michael C Owen
- CEITEC - Central European Institute of Technology, Masaryk University, Kamenice 753/5, Brno 625 00, Czech Republic
| | - David Gnutt
- Institute of Physical and Theoretical Chemistry, TU Braunschweig, Rebenring 56, 38106 Braunschweig, Germany and Lead Discovery Wuppertal, Bayer AG, 42096 Wuppertal, Germany
| | - Mimi Gao
- Faculty of Chemistry and Chemical Biology, TU Dortmund University, Otto-Hahn Str. 4a, 44227 Dortmund, Germany and Sanofi-Aventis Deutschland GmbH, R&D, Industriepark Höchst, 65926 Frankfurt, Germany
| | - Sebastian K T S Wärmländer
- Department of Biochemistry and Biophysics, Stockholm University, Svante Arrhenius väg 16C, 106 91 Stockholm, Sweden
| | - Jüri Jarvet
- Department of Biochemistry and Biophysics, Stockholm University, Svante Arrhenius väg 16C, 106 91 Stockholm, Sweden
| | - Astrid Gräslund
- Department of Biochemistry and Biophysics, Stockholm University, Svante Arrhenius väg 16C, 106 91 Stockholm, Sweden
| | - Roland Winter
- Faculty of Chemistry and Chemical Biology, TU Dortmund University, Otto-Hahn Str. 4a, 44227 Dortmund, Germany
| | - Simon Ebbinghaus
- Institute of Physical and Theoretical Chemistry, TU Braunschweig, Rebenring 56, 38106 Braunschweig, Germany
| | - Birgit Strodel
- Institute of Complex Systems: Structural Biochemistry, Forschungszentrum Jülich, 42525 Jülich, Germany. and Institute of Theoretical and Computational Chemistry, Heinrich Heine University Düsseldorf, Universitätsstraße 1, 40225 Düsseldorf, Germany
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56
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Christensen M, Schiøtt B. Revealing a Dual Role of Ganglioside Lipids in the Aggregation of Membrane-Associated Islet Amyloid Polypeptide. J Membr Biol 2019; 252:343-356. [DOI: 10.1007/s00232-019-00074-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2019] [Accepted: 06/09/2019] [Indexed: 12/31/2022]
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Gerst F, Wagner R, Oquendo MB, Siegel-Axel D, Fritsche A, Heni M, Staiger H, Häring HU, Ullrich S. What role do fat cells play in pancreatic tissue? Mol Metab 2019; 25:1-10. [PMID: 31113756 PMCID: PMC6600604 DOI: 10.1016/j.molmet.2019.05.001] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/22/2019] [Revised: 04/10/2019] [Accepted: 05/01/2019] [Indexed: 02/07/2023] Open
Abstract
Background It is now generally accepted that obesity is a major risk factor for type 2 diabetes mellitus (T2DM). Hepatic steatosis in particular, as well as visceral and ectopic fat accumulation within tissues, is associated with the development of the disease. We recently presented the first study on isolated human pancreatic adipocytes and their interaction with islets [Gerst, F., Wagner, R., Kaiser, G., Panse, M., Heni, M., Machann, J., et al., 2017. Metabolic crosstalk between fatty pancreas and fatty liver: effects on local inflammation and insulin secretion. Diabetologia 60(11):2240–2251.]. The results indicate that the function of adipocytes depends on the overall metabolic status in humans which, in turn, differentially affects islet hormone release. Scope of Review This review summarizes former and recent studies on factors derived from adipocytes and their effects on insulin-secreting β-cells, with particular emphasis on the human pancreas. The adipocyte secretome is discussed with a special focus on its influence on insulin secretion, β-cell survival and apoptotic β-cell death. Major Conclusions Human pancreatic adipocytes store lipids and release adipokines, metabolites, and pro-inflammatory molecules in response to the overall metabolic, humoral, and neuronal status. The differentially regulated adipocyte secretome impacts on endocrine function, i.e., insulin secretion, β-cell survival and death which interferes with glycemic control. This review attempts to explain why the extent of pancreatic steatosis is associated with reduced insulin secretion in some studies but not in others.
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Affiliation(s)
- Felicia Gerst
- German Center for Diabetes Research (DZD), Tübingen, Germany; Institute for Diabetes Research and Metabolic Diseases, Helmholtz Center Munich, Eberhard Karls University of Tübingen, Tübingen, Germany
| | - Robert Wagner
- German Center for Diabetes Research (DZD), Tübingen, Germany; Institute for Diabetes Research and Metabolic Diseases, Helmholtz Center Munich, Eberhard Karls University of Tübingen, Tübingen, Germany; Department of Internal Medicine IV, Division of Endocrinology, Diabetology, and Nephrology, University Hospital Tübingen, Tübingen, Germany
| | - Morgana Barroso Oquendo
- German Center for Diabetes Research (DZD), Tübingen, Germany; Department of Internal Medicine IV, Division of Endocrinology, Diabetology, and Nephrology, University Hospital Tübingen, Tübingen, Germany
| | - Dorothea Siegel-Axel
- German Center for Diabetes Research (DZD), Tübingen, Germany; Department of Internal Medicine IV, Division of Endocrinology, Diabetology, and Nephrology, University Hospital Tübingen, Tübingen, Germany
| | - Andreas Fritsche
- German Center for Diabetes Research (DZD), Tübingen, Germany; Department of Internal Medicine IV, Division of Endocrinology, Diabetology, and Nephrology, University Hospital Tübingen, Tübingen, Germany
| | - Martin Heni
- German Center for Diabetes Research (DZD), Tübingen, Germany; Institute for Diabetes Research and Metabolic Diseases, Helmholtz Center Munich, Eberhard Karls University of Tübingen, Tübingen, Germany; Department of Internal Medicine IV, Division of Endocrinology, Diabetology, and Nephrology, University Hospital Tübingen, Tübingen, Germany
| | - Harald Staiger
- German Center for Diabetes Research (DZD), Tübingen, Germany; Institute for Diabetes Research and Metabolic Diseases, Helmholtz Center Munich, Eberhard Karls University of Tübingen, Tübingen, Germany; Institute of Pharmaceutical Sciences, Department of Pharmacy and Biochemistry, Eberhard Karls University Tübingen, Tübingen, Germany
| | - Hans-Ulrich Häring
- German Center for Diabetes Research (DZD), Tübingen, Germany; Institute for Diabetes Research and Metabolic Diseases, Helmholtz Center Munich, Eberhard Karls University of Tübingen, Tübingen, Germany; Department of Internal Medicine IV, Division of Endocrinology, Diabetology, and Nephrology, University Hospital Tübingen, Tübingen, Germany
| | - Susanne Ullrich
- German Center for Diabetes Research (DZD), Tübingen, Germany; Institute for Diabetes Research and Metabolic Diseases, Helmholtz Center Munich, Eberhard Karls University of Tübingen, Tübingen, Germany.
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Ilie IM, Caflisch A. Simulation Studies of Amyloidogenic Polypeptides and Their Aggregates. Chem Rev 2019; 119:6956-6993. [DOI: 10.1021/acs.chemrev.8b00731] [Citation(s) in RCA: 93] [Impact Index Per Article: 18.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Affiliation(s)
- Ioana M. Ilie
- Department of Biochemistry, University of Zürich, Zürich CH-8057, Switzerland
| | - Amedeo Caflisch
- Department of Biochemistry, University of Zürich, Zürich CH-8057, Switzerland
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Ratha BN, Kar RK, Kalita S, Kalita S, Raha S, Singha A, Garai K, Mandal B, Bhunia A. Sequence specificity of amylin-insulin interaction: a fragment-based insulin fibrillation inhibition study. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2019; 1867:405-415. [DOI: 10.1016/j.bbapap.2019.01.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2018] [Revised: 01/03/2019] [Accepted: 01/13/2019] [Indexed: 01/10/2023]
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Sivanesam K, Andersen N. Pre-structured hydrophobic peptide β-strands: A universal amyloid trap? Arch Biochem Biophys 2019; 664:51-61. [PMID: 30707943 PMCID: PMC7094768 DOI: 10.1016/j.abb.2019.01.032] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2018] [Revised: 01/28/2019] [Accepted: 01/28/2019] [Indexed: 01/21/2023]
Abstract
Amyloid fibril formation has long been studied because of the variety of proteins that are capable of adopting this structure despite sharing little sequence homology. This makes amyloid fibrils a challenging focus for inhibition studies because the peptides and proteins that form amyloid fibrils cannot be targeted based on a sequence motif. Most peptide inhibitors that target specific amyloidogenic proteins rely heavily on sequence recognition to ensure that the inhibitory peptide is able to bind its target. This approach is limited to targeting one amyloidogenic protein at a time. However, there is increasing evidence of cross-reactivity between amyloid-forming polypeptides. It has therefore become more useful to study the similarities between these proteins that goes beyond their sequence homology. Indeed, the observation that amyloidogenic proteins adopt similar secondary structures along the pathway to fibril formation opens the way to an interesting investigation: the development of inhibitors that could be universal amyloid traps. The review below will analyze two specific amyloidogenic proteins, α-synuclein and human amylin, and introduce a small number of peptides that have been shown to be capable of inhibiting the amyloidogenesis of both of these very dissimilar polypeptides. Some of the inhibitory peptide motifs may indeed, be applicable to Aβ and other amyloidogenic systems.
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Hao X, Zheng J, Sun Y, Dong X. Seeding and Cross-Seeding Aggregations of Aβ 40 and Its N-Terminal-Truncated Peptide Aβ 11-40. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2019; 35:2821-2831. [PMID: 30681866 DOI: 10.1021/acs.langmuir.8b03599] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
In the amyloid plaques of Alzheimer's disease (AD) patients, a large number of N-terminal-truncated amyloid β (Aβ) peptides such as Aβ11-40 have been identified in addition to the full-length Aβ peptides. However, little is known about the roles of the N-terminal-truncated peptides in AD pathological process. Herein, seeding and cross-seeding aggregations of Aβ40 and its N-terminal-truncated Aβ11-40 were investigated in the solution and on the surfaces of chips with immobilized seeds by extensive biophysical and biological analyses. The results showed that Aβ40 and Aβ11-40 aggregates could seed both homologous and heterologous aggregations of the two monomers. However, the capability and characteristics of the seeding (homologous aggregation) and cross-seeding (heterologous aggregation) were significantly different. Aβ40 seeds showed stronger acceleration effects on the aggregations than Aβ11-40 seeds and induced β-sheet-rich fibrous aggregates of similar cytotoxicities for the two monomers. This indicates that Aβ40 and Aβ11-40 had similar aggregation pathways in the seeding and cross-seeding on Aβ40 seeds. By contrast, Aβ11-40 seeds led to different aggregation pathways of Aβ40 and Aβ11-40. Pure Aβ11-40 aggregates had higher toxicity than Aβ40 aggregates, and as seeds, Aβ11-40 seeds induced Aβ40 to form aggregates of higher cytotoxicity. However, homologous Aβ11-40 aggregates induced by Aβ11-40 seeds showed lower cytotoxicity than pure Aβ11-40 aggregates. The results suggest that Aβ11-40 plays an important role in the pathological process of AD.
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Affiliation(s)
- Xiuping Hao
- Department of Biochemical Engineering and Key Laboratory of Systems Bioengineering of the Ministry of Education, School of Chemical Engineering and Technology , Tianjin University , Tianjin 300072 , China
| | - Jie Zheng
- Department of Chemical and Biomolecular Engineering , The University of Akron , Akron , Ohio 44325 , United States
| | - Yan Sun
- Department of Biochemical Engineering and Key Laboratory of Systems Bioengineering of the Ministry of Education, School of Chemical Engineering and Technology , Tianjin University , Tianjin 300072 , China
| | - Xiaoyan Dong
- Department of Biochemical Engineering and Key Laboratory of Systems Bioengineering of the Ministry of Education, School of Chemical Engineering and Technology , Tianjin University , Tianjin 300072 , China
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Qiao Q, Wei G, Yao D, Song Z. Formation of α-helical and β-sheet structures in membrane-bound human IAPP monomer and the resulting membrane deformation. Phys Chem Chem Phys 2019; 21:20239-20251. [DOI: 10.1039/c9cp03151k] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Upon adsorption on membrane, human IAPP monomer takes conformational changes from coils to α-helices and β-sheets. The helices inserted and β on surface cause different types of membrane deformation, implying two distinct aggregation mechanisms.
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Affiliation(s)
- Qin Qiao
- Digital Medical Research Center
- School of Basic Medical Sciences
- Fudan University
- Shanghai 200032
- China
| | - Guanghong Wei
- Department of Physics
- State Key Laboratory of Surface Physics
- Key Laboratory for Computational Physical Science (Ministry of Education)
- Fudan University
- Shanghai 200438
| | - Demin Yao
- Digital Medical Research Center
- School of Basic Medical Sciences
- Fudan University
- Shanghai 200032
- China
| | - Zhijian Song
- Digital Medical Research Center
- School of Basic Medical Sciences
- Fudan University
- Shanghai 200032
- China
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63
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Divakara MB, Martinez D, Ravi A, Bhavana V, Ramana V, Habenstein B, Loquet A, Santosh MS. Molecular mechanisms for the destabilization of model membranes by islet amyloid polypeptide. Biophys Chem 2018; 245:34-40. [PMID: 30576976 DOI: 10.1016/j.bpc.2018.12.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Revised: 11/29/2018] [Accepted: 12/10/2018] [Indexed: 12/30/2022]
Abstract
Misfolding of human islet amyloid polypeptide (hIAPP) into insoluble aggregates is associated with Type 2 diabetes. It has been suggested that hIAPP toxicity may be due to its accumulation in pancreatic islets, causing membrane disruption and cell permeabilization, however the molecular basis underlying its lipid association are still unclear. Here, we combine solid-state NMR, fluorescence and bright field microscopy to investigate hIAPP - lipid membrane interactions. Real-time microscopy highlights a time-dependent penetration of hIAPP oligomers toward the most buried layers of the lipid vesicles until the membrane disrupts. Deuterium NMR was conducted on liposomes at different hIAPP concentration to probe lipid internal order and thermotropism. The gel-to-fluid phase transition of the lipids is decreased by the presence of hIAPP, and site-specific analysis of the order parameter showed a significant increase of lipid order for the first eight positions of the acyl chain, suggesting a partial insertion of the peptide inside the bilayer. These results offer experimental insight into the membrane destabilization of hIAPP on model membrane vesicles.
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Affiliation(s)
- Madhihalli Basavaraju Divakara
- Center for Incubation, Innovation, Research and Consultancy (CIIRC), Jyothy Institute of Technology, Thataguni, Off Kanakapura Road, Bangalore 560082, Karnataka, India; Visvesvaraya Technological University, Regional Research Centre, Jnana Sangama, Belagavi 590018, Karnataka, India
| | - Denis Martinez
- Institute of Chemistry and Biology of Membranes and Nanoobjects, Institut Européen de Chimie et Biologie (CNRS UMR 5248), Université de Bordeaux, 2 Rue Robert Escarpit, 33600 Pessac, France
| | - Ashwini Ravi
- Center for Incubation, Innovation, Research and Consultancy (CIIRC), Jyothy Institute of Technology, Thataguni, Off Kanakapura Road, Bangalore 560082, Karnataka, India; Visvesvaraya Technological University, Regional Research Centre, Jnana Sangama, Belagavi 590018, Karnataka, India
| | - Veer Bhavana
- Center for Incubation, Innovation, Research and Consultancy (CIIRC), Jyothy Institute of Technology, Thataguni, Off Kanakapura Road, Bangalore 560082, Karnataka, India; Visvesvaraya Technological University, Regional Research Centre, Jnana Sangama, Belagavi 590018, Karnataka, India
| | - Venkata Ramana
- DRDO BU CLS, Bharathiar University Campus, Coimbatore 641046, Tamil Nadu, India
| | - Birgit Habenstein
- Institute of Chemistry and Biology of Membranes and Nanoobjects, Institut Européen de Chimie et Biologie (CNRS UMR 5248), Université de Bordeaux, 2 Rue Robert Escarpit, 33600 Pessac, France.
| | - Antoine Loquet
- Institute of Chemistry and Biology of Membranes and Nanoobjects, Institut Européen de Chimie et Biologie (CNRS UMR 5248), Université de Bordeaux, 2 Rue Robert Escarpit, 33600 Pessac, France.
| | - Mysore Sridhar Santosh
- Center for Incubation, Innovation, Research and Consultancy (CIIRC), Jyothy Institute of Technology, Thataguni, Off Kanakapura Road, Bangalore 560082, Karnataka, India.
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Kakinen A, Sun Y, Javed I, Faridi A, Pilkington EH, Faridi P, Purcell AW, Zhou R, Ding F, Lin S, Chun Ke P, Davis TP. Physical and Toxicological Profiles of Human IAPP Amyloids and Plaques. Sci Bull (Beijing) 2018; 64:26-35. [PMID: 30662791 DOI: 10.1016/j.scib.2018.11.012] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Although much has been learned about the fibrillization kinetics, structure and toxicity of amyloid proteins, the properties of amyloid fibrils beyond the saturation phase are often perceived as chemically and biologically inert, despite evidence suggesting otherwise. To fill this knowledge gap, we examined the physical and biological characteristics of human islet amyloid polypeptide (IAPP) fibrils that were aged up to two months. Not only did aging decrease the toxicity of IAPP fibrils, but the fibrils also sequestered fresh IAPP and suppressed their toxicity in an embryonic zebrafish model. The mechanical properties of IAPP fibrils in different aging stages were probed by atomic force microscopy and sonication, which displayed comparable stiffness but age-dependent fragmentation, followed by self-assembly of such fragments into the largest lamellar amyloid structures reported to date. The dynamic structural and toxicity profiles of amyloid fibrils and plaques suggest that they play active, long-term roles in cell degeneration and may be a therapeutic target for amyloid diseases.
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Affiliation(s)
- Aleksandr Kakinen
- ARC Centre of Excellence in Convergent Bio-Nano Science and Technology, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade Parkville, VIC 3052, Australia
| | - Yunxiang Sun
- Department of Physics and Astronomy, Clemson University, Clemson, SC 29634, USA
| | - Ibrahim Javed
- ARC Centre of Excellence in Convergent Bio-Nano Science and Technology, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade Parkville, VIC 3052, Australia.,College of Environmental Science and Engineering, Shanghai Institute of Pollution Control and Ecological Security, Biomedical Multidisciplinary Innovation Research Institute, Shanghai East Hospital, Tongji University, 1239 Siping Road, Shanghai 200092, China
| | - Ava Faridi
- ARC Centre of Excellence in Convergent Bio-Nano Science and Technology, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade Parkville, VIC 3052, Australia
| | - Emily H Pilkington
- ARC Centre of Excellence in Convergent Bio-Nano Science and Technology, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade Parkville, VIC 3052, Australia
| | - Pouya Faridi
- Department of Biochemistry and Molecular Biology, Infection and Immunity Program & Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia
| | - Anthony W Purcell
- Department of Biochemistry and Molecular Biology, Infection and Immunity Program & Biomedicine Discovery Institute, Monash University, Clayton, Victoria 3800, Australia
| | - Ruhong Zhou
- IBM Thomas J. Watson Research Center, Yorktown Heights, New York, 10598, USA.,Department of Chemistry, Columbia University, New York, New York, 10027, USA
| | - Feng Ding
- Department of Physics and Astronomy, Clemson University, Clemson, SC 29634, USA
| | - Sijie Lin
- College of Environmental Science and Engineering, Shanghai Institute of Pollution Control and Ecological Security, Biomedical Multidisciplinary Innovation Research Institute, Shanghai East Hospital, Tongji University, 1239 Siping Road, Shanghai 200092, China
| | - Pu Chun Ke
- ARC Centre of Excellence in Convergent Bio-Nano Science and Technology, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade Parkville, VIC 3052, Australia
| | - Thomas P Davis
- ARC Centre of Excellence in Convergent Bio-Nano Science and Technology, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade Parkville, VIC 3052, Australia
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Rawat A, Maity BK, Chandra B, Maiti S. Aggregation-induced conformation changes dictate islet amyloid polypeptide (IAPP) membrane affinity. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2018; 1860:1734-1740. [DOI: 10.1016/j.bbamem.2018.03.027] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Revised: 03/20/2018] [Accepted: 03/21/2018] [Indexed: 11/30/2022]
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66
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Press-Sandler O, Miller Y. Molecular mechanisms of membrane-associated amyloid aggregation: Computational perspective and challenges. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2018; 1860:1889-1905. [DOI: 10.1016/j.bbamem.2018.03.014] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2018] [Revised: 03/07/2018] [Accepted: 03/12/2018] [Indexed: 01/02/2023]
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67
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Hoffmann AR, Saravanan MS, Lequin O, Killian JA, Khemtemourian L. A single mutation on the human amyloid polypeptide modulates fibril growth and affects the mechanism of amyloid-induced membrane damage. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2018; 1860:1783-1792. [DOI: 10.1016/j.bbamem.2018.02.018] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Revised: 02/19/2018] [Accepted: 02/20/2018] [Indexed: 12/30/2022]
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68
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IAPP in type II diabetes: Basic research on structure, molecular interactions, and disease mechanisms suggests potential intervention strategies. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2018. [DOI: 10.1016/j.bbamem.2018.02.020] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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69
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Kiriyama Y, Nochi H. Role and Cytotoxicity of Amylin and Protection of Pancreatic Islet β-Cells from Amylin Cytotoxicity. Cells 2018; 7:cells7080095. [PMID: 30082607 PMCID: PMC6115925 DOI: 10.3390/cells7080095] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2018] [Revised: 07/28/2018] [Accepted: 08/01/2018] [Indexed: 12/26/2022] Open
Abstract
Amylin, (or islet amyloid polypeptide; IAPP), a 37-amino acid peptide hormone, is released in response to nutrients, including glucose, lipids or amino acids. Amylin is co-stored and co-secreted with insulin by pancreatic islet β-cells. Amylin inhibits food intake, delays gastric emptying, and decreases blood glucose levels, leading to the reduction of body weight. Therefore, amylin as well as insulin play important roles in controlling the level of blood glucose. However, human amylin aggregates and human amylin oligomers cause membrane disruption, endoplasmic reticulum (ER) stress and mitochondrial damage. Since cytotoxicity of human amylin oligomers to pancreatic islet β-cells can lead to diabetes, the protection of pancreatic islet β cells from cytotoxic amylin is crucial. Human amylin oligomers also inhibit autophagy, although autophagy can function to remove amylin aggregates and damaged organelles. Small molecules, including β-sheet breaker peptides, chemical chaperones, and foldamers, inhibit and disaggregate amyloid formed by human amylin, suggesting the possible use of these small molecules in the treatment of diabetes. In this review, we summarize recent findings regarding the role and cytotoxicity of amylin and the protection of pancreatic islet β-cells from cytotoxicity of amylin.
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Affiliation(s)
- Yoshimitsu Kiriyama
- Kagawa School of Pharmaceutical Sciences, Tokushima Bunri University, Shido 1314-1, Kagawa, Sanuki 769-2193, Japan.
| | - Hiromi Nochi
- Kagawa School of Pharmaceutical Sciences, Tokushima Bunri University, Shido 1314-1, Kagawa, Sanuki 769-2193, Japan.
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70
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Fernández-Pérez EJ, Sepúlveda FJ, Peters C, Bascuñán D, Riffo-Lepe NO, González-Sanmiguel J, Sánchez SA, Peoples RW, Vicente B, Aguayo LG. Effect of Cholesterol on Membrane Fluidity and Association of Aβ Oligomers and Subsequent Neuronal Damage: A Double-Edged Sword. Front Aging Neurosci 2018; 10:226. [PMID: 30123122 PMCID: PMC6085471 DOI: 10.3389/fnagi.2018.00226] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2018] [Accepted: 07/03/2018] [Indexed: 02/06/2023] Open
Abstract
Background: The beta-amyloid peptide (Aβ) involved in Alzheimer's disease (AD) has been described to associate/aggregate on the cell surface disrupting the membrane through pore formation and breakage. However, molecular determinants involved for this interaction (e.g., some physicochemical properties of the cell membrane) are largely unknown. Since cholesterol is an important molecule for membrane structure and fluidity, we examined the effect of varying cholesterol content with the association and membrane perforation by Aβ in cultured hippocampal neurons. Methods: To decrease or increase the levels of cholesterol in the membrane we used methyl-β-cyclodextrin (MβCD) and MβCD/cholesterol, respectively. We analyzed if membrane fluidity was affected using generalized polarization (GP) imaging and the fluorescent dye di-4-ANEPPDHQ. Additionally membrane association and perforation was assessed using immunocytochemistry and electrophysiological techniques, respectively. Results: The results showed that cholesterol removal decreased the macroscopic association of Aβ to neuronal membranes (fluorescent-puncta/20 μm: control = 18 ± 2 vs. MβCD = 10 ± 1, p < 0.05) and induced a facilitation of the membrane perforation by Aβ with respect to control cells (half-time for maximal charge transferred: control = 7.2 vs. MβCD = 4.4). Under this condition, we found an increase in membrane fluidity (46 ± 3.3% decrease in GP value, p < 0.001). On the contrary, increasing cholesterol levels incremented membrane rigidity (38 ± 2.7% increase in GP value, p < 0.001) and enhanced the association and clustering of Aβ (fluorescent-puncta/20 μm: control = 18 ± 2 vs. MβCD = 10 ± 1, p < 0.01), but inhibited membrane disruption. Conclusion: Our results strongly support the significance of plasma membrane organization in the toxic effects of Aβ in hippocampal neurons, since fluidity can regulate distribution and insertion of the Aβ peptide in the neuronal membrane.
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Affiliation(s)
- Eduardo J Fernández-Pérez
- Laboratory of Neurophysiology, Department of Physiology, Universidad de Concepción, Concepción, Chile
| | - Fernando J Sepúlveda
- Laboratory of Neurophysiology, Department of Physiology, Universidad de Concepción, Concepción, Chile
| | - Christian Peters
- Laboratory of Neurophysiology, Department of Physiology, Universidad de Concepción, Concepción, Chile
| | - Denisse Bascuñán
- Laboratory of Neurophysiology, Department of Physiology, Universidad de Concepción, Concepción, Chile
| | - Nicolás O Riffo-Lepe
- Laboratory of Neurophysiology, Department of Physiology, Universidad de Concepción, Concepción, Chile
| | | | - Susana A Sánchez
- Departamento de Polímeros, Facultad de Ciencias Químicas, Universidad de Concepción, Concepción, Chile
| | - Robert W Peoples
- Department of Biomedical Sciences, Marquette University, Milwaukee, WI, United States
| | - Benjamín Vicente
- Department of Psychiatry and Mental Health, Universidad de Concepción, Concepción, Chile
| | - Luis G Aguayo
- Laboratory of Neurophysiology, Department of Physiology, Universidad de Concepción, Concepción, Chile
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71
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Li Y, Wang X, Ren L, Cao X, Ji C, Xia F, Zhang JZH. Electrostatic Polarization Effect on Cooperative Aggregation of Full Length Human Islet Amyloid. J Chem Inf Model 2018; 58:1587-1595. [DOI: 10.1021/acs.jcim.8b00215] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Affiliation(s)
- Yang Li
- College of Information Science and Engineering, Shandong Agricultural University, Taian 271018, China
- College of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200062, China
| | - Xianwei Wang
- Institute of Laser and Optoelectronic Technology, Zhejiang University of Technology, Hangzhou 310023, China
| | - Longlong Ren
- College of Mechanical and Electronic Engineering, Shandong Agricultural University, Taian 271018, China
| | - Xuecheng Cao
- College of Information Science and Engineering, Shandong Agricultural University, Taian 271018, China
| | - Changge Ji
- College of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200062, China
- NYU-ECNU Center for Computational Chemistry at NYU Shanghai, Shanghai 200062, China
| | - Fei Xia
- College of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200062, China
- NYU-ECNU Center for Computational Chemistry at NYU Shanghai, Shanghai 200062, China
| | - John Z. H. Zhang
- College of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200062, China
- NYU-ECNU Center for Computational Chemistry at NYU Shanghai, Shanghai 200062, China
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72
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Guo AZ, Fluitt AM, de Pablo JJ. Early-stage human islet amyloid polypeptide aggregation: Mechanisms behind dimer formation. J Chem Phys 2018; 149:025101. [DOI: 10.1063/1.5033458] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Affiliation(s)
- Ashley Z. Guo
- Institute for Molecular Engineering, University of Chicago, Chicago, Illinois 60637, USA
| | - Aaron M. Fluitt
- Institute for Molecular Engineering, University of Chicago, Chicago, Illinois 60637, USA
| | - Juan J. de Pablo
- Institute for Molecular Engineering, University of Chicago, Chicago, Illinois 60637, USA
- Materials Science Division, Argonne National Laboratory, Argonne, Illinois 60439, USA
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73
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Abedini A, Derk J, Schmidt AM. The receptor for advanced glycation endproducts is a mediator of toxicity by IAPP and other proteotoxic aggregates: Establishing and exploiting common ground for novel amyloidosis therapies. Protein Sci 2018; 27:1166-1180. [PMID: 29664151 PMCID: PMC6032365 DOI: 10.1002/pro.3425] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2018] [Revised: 04/09/2018] [Accepted: 04/10/2018] [Indexed: 12/23/2022]
Abstract
Proteotoxicity plays a key role in many devastating human disorders, including Alzheimer's, Huntington's and Parkinson's diseases; type 2 diabetes; systemic amyloidosis; and cardiac dysfunction, to name a few. The cellular mechanisms of proteotoxicity in these disorders have been the focus of considerable research, but their role in prevalent and morbid disorders, such as diabetes, is less appreciated. There is a large body of literature on the impact of glucotoxicity and lipotoxicity on insulin-producing pancreatic β-cells, and there is increasing recognition that proteotoxicty plays a key role. Pancreatic islet amyloidosis by the hormone IAPP, the production of advanced glycation endproducts (AGE), and insulin misprocessing into cytotoxic aggregates are all sources of β-cell proteotoxicity in diabetes. AGE, produced by the reaction of reducing sugars with proteins and lipids are ligands for the receptor for AGE (RAGE), as are the toxic pre-fibrillar aggregates of IAPP produced during amyloid formation. The mechanisms of amyloid formation by IAPP in vivo or in vitro are not well understood, and the cellular mechanisms of IAPP-induced β-cell death are not fully defined. Here, we review recent findings that illuminate the factors and mechanisms involved in β-cell proteotoxicity in diabetes. Together, these new insights have far-reaching implications for the establishment of unifying mechanisms by which pathological amyloidoses imbue their injurious effects in vivo.
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Affiliation(s)
- Andisheh Abedini
- Diabetes Research Program, Division of Endocrinology, Department of MedicineNew York University Medical Center, 550 First Avenue, Smilow 906New YorkNew York10016
| | - Julia Derk
- Diabetes Research Program, Division of Endocrinology, Department of MedicineNew York University Medical Center, 550 First Avenue, Smilow 906New YorkNew York10016
| | - Ann Marie Schmidt
- Diabetes Research Program, Division of Endocrinology, Department of MedicineNew York University Medical Center, 550 First Avenue, Smilow 906New YorkNew York10016
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74
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Greenwald J, Kwiatkowski W, Riek R. Peptide Amyloids in the Origin of Life. J Mol Biol 2018; 430:3735-3750. [PMID: 29890117 DOI: 10.1016/j.jmb.2018.05.046] [Citation(s) in RCA: 65] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2018] [Revised: 05/29/2018] [Accepted: 05/31/2018] [Indexed: 10/14/2022]
Abstract
How life can emerge from non-living matter is one of the fundamental mysteries of the universe. A bottom-up approach to this problem focuses on the potential chemical precursors of life, in particular the nature of the first replicative molecules. Such thinking has led to the currently most popular idea: that an RNA-like molecule played a central role as the first replicative and catalytic molecule. Here, we review an alternative hypothesis that has recently gained experimental support, focusing on the role of amyloidogenic peptides rather than nucleic acids, in what has been by some termed "the amyloid-world" hypothesis. Amyloids are well-ordered peptide aggregates that have a fibrillar morphology due to their underlying structure of a one-dimensional crystal-like array of peptides in a β-strand conformation. While they are notorious for their implication in several neurodegenerative diseases including Alzheimer's disease, amyloids also have many biological functions. In this review, we will elaborate on the following properties of amyloids in relation to their fitness as a prebiotic entity: they can be formed by very short peptides with simple amino acids sequences; as aggregates they are more chemically stable than their isolated component peptides; they can possess diverse catalytic activities; they can form spontaneously during the prebiotic condensation of amino acids; they can act as templates in their own chemical replication; they have a structurally repetitive nature that enables them to interact with other structurally repetitive biopolymers like RNA/DNA and polysaccharides, as well as with structurally repetitive surfaces like amphiphilic membranes and minerals.
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Affiliation(s)
- Jason Greenwald
- Laboratory of Physical Chemistry, Swiss Federal Institute of Technology, ETH-Hönggerberg, CH-8093 Zürich, Switzerland
| | - Witek Kwiatkowski
- Laboratory of Physical Chemistry, Swiss Federal Institute of Technology, ETH-Hönggerberg, CH-8093 Zürich, Switzerland
| | - Roland Riek
- Laboratory of Physical Chemistry, Swiss Federal Institute of Technology, ETH-Hönggerberg, CH-8093 Zürich, Switzerland.
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75
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Rawat A, Langen R, Varkey J. Membranes as modulators of amyloid protein misfolding and target of toxicity. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2018; 1860:1863-1875. [PMID: 29702073 DOI: 10.1016/j.bbamem.2018.04.011] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2018] [Revised: 04/19/2018] [Accepted: 04/19/2018] [Indexed: 12/15/2022]
Abstract
Abnormal protein aggregation is a hallmark of various human diseases. α-Synuclein, a protein implicated in Parkinson's disease, is found in aggregated form within Lewy bodies that are characteristically observed in the brains of PD patients. Similarly, deposits of aggregated human islet amyloid polypeptide (IAPP) are found in the pancreatic islets in individuals with type 2 diabetes mellitus. Significant number of studies have focused on how monomeric, disaggregated proteins transition into various amyloid structures leading to identification of a vast number of aggregation promoting molecules and processes over the years. Inasmuch as these factors likely enhance the formation of toxic, misfolded species, they might act as risk factors in disease. Cellular membranes, and particularly certain lipids, are considered to be among the major players for aggregation of α-synuclein and IAPP, and membranes might also be the target of toxicity. Past studies have utilized an array of biophysical tools, both in vitro and in vivo, to expound the membrane-mediated aggregation. Here, we focus on membrane interaction of α-synuclein and IAPP, and how various kinds of membranes catalyze or modulate the aggregation of these proteins and how, in turn, these proteins disrupt membrane integrity, both in vitro and in vivo. The membrane interaction and subsequent aggregation has been briefly contrasted to aggregation of α-synuclein and IAPP in solution. This article is part of a Special Issue entitled: Protein Aggregation and Misfolding at the Cell Membrane Interface edited by Ayyalusamy Ramamoorthy.
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Affiliation(s)
- Anoop Rawat
- Zilkha Neurogenetic Institute, University of Southern California, Los Angeles, CA 90033, United States
| | - Ralf Langen
- Zilkha Neurogenetic Institute, University of Southern California, Los Angeles, CA 90033, United States.
| | - Jobin Varkey
- Zilkha Neurogenetic Institute, University of Southern California, Los Angeles, CA 90033, United States.
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76
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Sasahara K. Membrane-mediated amyloid deposition of human islet amyloid polypeptide. Biophys Rev 2018; 10:453-462. [PMID: 29204886 PMCID: PMC5899711 DOI: 10.1007/s12551-017-0351-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2017] [Accepted: 11/14/2017] [Indexed: 01/01/2023] Open
Abstract
Amyloid deposition of human islet amyloid polypeptide (hIAPP) within the islet of Langerhans is closely associated with type II diabetes mellitus. Accumulating evidence indicates that the membrane-mediated aggregation and subsequent deposition of hIAPP are linked to the dysfunction and death of insulin-producing pancreatic β-cells, but the molecular process of hIAPP deposition is poorly understood. In this review, I focus on recent in vitro studies utilizing model membranes to observe the membrane-mediated aggregation/deposition of hIAPP. Membrane surfaces can serve as templates for both hIAPP adsorption and aggregation. Using high-sensitivity surface analyzing/imaging techniques that can characterize the processes of hIAPP aggregation and deposition at the membrane surface, these studies provide valuable insights into the mechanism of membrane damage caused by amyloid deposition of the peptide.
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Affiliation(s)
- Kenji Sasahara
- Institute for Protein Research, Osaka University, 3-2 Yamadaoka, Suita, Osaka, 565-0871, Japan.
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77
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Press M, Jung T, König J, Grune T, Höhn A. Protein aggregates and proteostasis in aging: Amylin and β-cell function. Mech Ageing Dev 2018; 177:46-54. [PMID: 29580826 DOI: 10.1016/j.mad.2018.03.010] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2018] [Accepted: 03/22/2018] [Indexed: 01/07/2023]
Abstract
The ubiquitin-proteasomal-system (UPS) and the autophagy-lysosomal-system (ALS) are both highly susceptible for disturbances leading to the accumulation of cellular damage. A decline of protein degradation during aging results in the formation of oxidatively damaged and aggregated proteins finally resulting in failure of cellular functionality. Besides protein aggregation in response to oxidative damage, amyloids are a different type of protein aggregates able to distract proteostasis and interfere with cellular functionality. Amyloids are clearly linked to the pathogenesis of age-related degenerative diseases such as Alzheimer's disease. Human amylin is one of the peptides forming fibrils in β-sheet conformation finally leading to amyloid formation. In contrast to rodent amylin, human amylin is prone to form amyloidogenic aggregates, proposed to play a role in the pathogenesis of Type 2 Diabetes by impairing β-cell functionality. Since aggregates such as lipofuscin and β-amyloid are known to impair proteostasis, it is likely to assume similar effects for human amylin. In this review, we focus on the effects of IAPP on UPS and ALS and their role in amylin degradation, since both systems play a crucial role in maintaining proteome balance thereby influencing, at least in part, cellular fate and aging.
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Affiliation(s)
- Michaela Press
- Department of Molecular Toxicology, German Institute of Human Nutrition Potsdam-Rehbruecke (DIfE), 14558 Nuthetal, Germany; German Center for Diabetes Research (DZD), 85764 Muenchen-Neuherberg, Germany.
| | - Tobias Jung
- Department of Molecular Toxicology, German Institute of Human Nutrition Potsdam-Rehbruecke (DIfE), 14558 Nuthetal, Germany; German Center for Cardiovascular Research (DZHK), 10117 Berlin, Germany.
| | - Jeannette König
- Department of Molecular Toxicology, German Institute of Human Nutrition Potsdam-Rehbruecke (DIfE), 14558 Nuthetal, Germany.
| | - Tilman Grune
- Department of Molecular Toxicology, German Institute of Human Nutrition Potsdam-Rehbruecke (DIfE), 14558 Nuthetal, Germany; German Center for Diabetes Research (DZD), 85764 Muenchen-Neuherberg, Germany; German Center for Cardiovascular Research (DZHK), 10117 Berlin, Germany; NutriAct - Competence Cluster Nutrition Research Berlin-Potsdam, 14558 Nuthetal, Germany; Institute of Nutrition, University of Potsdam, 14558 Nuthetal, Germany.
| | - Annika Höhn
- Department of Molecular Toxicology, German Institute of Human Nutrition Potsdam-Rehbruecke (DIfE), 14558 Nuthetal, Germany; German Center for Diabetes Research (DZD), 85764 Muenchen-Neuherberg, Germany.
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78
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Hajiraissi R, Hanke M, Yang Y, Duderija B, Gonzalez Orive A, Grundmeier G, Keller A. Adsorption and Fibrillization of Islet Amyloid Polypeptide at Self-Assembled Monolayers Studied by QCM-D, AFM, and PM-IRRAS. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2018; 34:3517-3524. [PMID: 29489382 DOI: 10.1021/acs.langmuir.7b03626] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Aggregation and fibrillization of human islet amyloid polypeptide (hIAPP) plays an important role in the development of type 2 diabetes mellitus. Understanding the interaction of hIAPP with interfaces such as cell membranes at a molecular level therefore represents an important step toward new therapies. Here, we investigate the fibrillization of hIAPP at different self-assembled alkanethiol monolayers (SAMs) by quartz crystal microbalance with dissipation monitoring (QCM-D), atomic force microscopy (AFM), and polarization-modulated infrared reflection absorption spectroscopy (PM-IRRAS). We find that hydrophobic interactions with the CH3-terminated SAM tend to retard hIAPP fibrillization compared to the carboxylic acid-terminated SAM where attractive electrostatic interactions lead to the formation of a three-dimensional network of interwoven fibrils. At the hydroxyl- and amino-terminated SAMs, fibrillization appears to be governed by hydrogen bonding between the peptide and the terminating groups which may even overcome electrostatic repulsion. These results thus provide fundamental insights into the molecular mechanisms governing amyloid assembly at interfaces.
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Affiliation(s)
- Roozbeh Hajiraissi
- Technical and Macromolecular Chemistry , Paderborn University , Warburger Str. 100 , 33098 Paderborn , Germany
| | - Marcel Hanke
- Technical and Macromolecular Chemistry , Paderborn University , Warburger Str. 100 , 33098 Paderborn , Germany
| | - Yu Yang
- Technical and Macromolecular Chemistry , Paderborn University , Warburger Str. 100 , 33098 Paderborn , Germany
| | - Belma Duderija
- Technical and Macromolecular Chemistry , Paderborn University , Warburger Str. 100 , 33098 Paderborn , Germany
| | - Alejandro Gonzalez Orive
- Technical and Macromolecular Chemistry , Paderborn University , Warburger Str. 100 , 33098 Paderborn , Germany
| | - Guido Grundmeier
- Technical and Macromolecular Chemistry , Paderborn University , Warburger Str. 100 , 33098 Paderborn , Germany
| | - Adrian Keller
- Technical and Macromolecular Chemistry , Paderborn University , Warburger Str. 100 , 33098 Paderborn , Germany
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79
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Sciacca MFM, Chillemi R, Sciuto S, Greco V, Messineo C, Kotler SA, Lee DK, Brender JR, Ramamoorthy A, La Rosa C, Milardi D. A blend of two resveratrol derivatives abolishes hIAPP amyloid growth and membrane damage. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2018; 1860:1793-1802. [PMID: 29555190 DOI: 10.1016/j.bbamem.2018.03.012] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2017] [Revised: 01/31/2018] [Accepted: 03/13/2018] [Indexed: 12/14/2022]
Abstract
Type II diabetes mellitus (T2DM) is characterized by the presence of amyloid deposits of the human islet amyloid polypeptide (hIAPP) in pancreatic β-cells. A wealth of data supports the hypothesis that hIAPP's toxicity is related to an abnormal interaction of amyloids with islet cell membranes. Thus, many studies aimed at finding effective therapies for T2DM focus on the design of molecules that are able to inhibit hIAPP's amyloid growth and the related membrane damage as well. Based on this view and inspired by its known anti-amyloid properties, we have functionalized resveratrol with a phosphoryl moiety (4'-O-PR) that improves its solubility and pharmacological properties. A second resveratrol derivative has also been obtained by conjugating resveratrol with a dimyristoylphosphatidyl moiety (4'-DMPR). The use of both compounds resulted in abolishing both amyloid growth and amyloid mediated POPC/POPS membrane damage in tube tests. We propose that a mixture of a water-soluble anti-aggregating compound and its lipid-anchored derivative may be employed as a general strategy to prevent and/or to halt amyloid-related membrane damage.
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Affiliation(s)
- Michele F M Sciacca
- Istituto CNR di Biostrutture e Bioimmagini- Sede Secondaria di Catania, Via Paolo Gaifami 18, 95126 Catania, Italy
| | - Rosa Chillemi
- Università degli Studi di Catania, Dipartimento di Scienze Chimiche, Viale Andrea Doria 6, 95125 Catania, Italy
| | - Sebastiano Sciuto
- Università degli Studi di Catania, Dipartimento di Scienze Chimiche, Viale Andrea Doria 6, 95125 Catania, Italy
| | - Valentina Greco
- Università degli Studi di Catania, Dipartimento di Scienze Chimiche, Viale Andrea Doria 6, 95125 Catania, Italy
| | - Concetta Messineo
- Università degli Studi di Catania, Dipartimento di Scienze Chimiche, Viale Andrea Doria 6, 95125 Catania, Italy
| | - Samuel A Kotler
- Biophysics and Department of Chemistry, University of Michigan, Ann Arbor, MI 48109-1055, USA
| | - Dong-Kuk Lee
- Department of Fine Chemistry, Seoul National University of Science and Technology, Seoul 01811, Republic of Korea
| | - Jeffrey R Brender
- Biophysics and Department of Chemistry, University of Michigan, Ann Arbor, MI 48109-1055, USA
| | - Ayyalusamy Ramamoorthy
- Biophysics and Department of Chemistry, University of Michigan, Ann Arbor, MI 48109-1055, USA
| | - Carmelo La Rosa
- Università degli Studi di Catania, Dipartimento di Scienze Chimiche, Viale Andrea Doria 6, 95125 Catania, Italy.
| | - Danilo Milardi
- Istituto CNR di Biostrutture e Bioimmagini- Sede Secondaria di Catania, Via Paolo Gaifami 18, 95126 Catania, Italy.
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80
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Zhang X, London E, Raleigh DP. Sterol Structure Strongly Modulates Membrane-Islet Amyloid Polypeptide Interactions. Biochemistry 2018; 57:1868-1879. [PMID: 29373018 DOI: 10.1021/acs.biochem.7b01190] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Amyloid formation has been implicated in a wide range of human diseases, and the interaction of amyloidogenic proteins with membranes are believed to be important for many of them. In type-2 diabetes, human islet amyloid polypeptide (IAPP) forms amyloids, which contribute to β-cell death and dysfunction in the disease. IAPP-membrane interactions are potential mechanisms of cytotoxicity. In vitro studies have shown that cholesterol significantly modulates the ability of model membranes to induce IAPP amyloid formation and IAPP-mediated membrane damage. It is not known if this is due to the general effects of cholesterol on membranes or because of specific sterol-IAPP interactions. The effects of replacing cholesterol with eight other sterols/steroids on IAPP binding to model membranes, membrane disruption, and membrane-mediated amyloid formation were examined. The primary effect of the sterols/steroids on the IAPP-membrane interactions was found to reflect their effect upon membrane order as judged by fluorescence anisotropy measurements. Specific IAPP-sterol/steroid interactions have smaller effects. The fraction of vesicles that bind IAPP was inversely correlated with the sterols/steroids' effect on membrane order, as was the extent of IAPP-induced membrane leakage and the time to form amyloids. The correlation between the fraction of vesicles binding IAPP and membrane leakage was particularly tight, suggesting the restriction of IAPP to a subset of vesicles is responsible for incomplete leakage.
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81
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Dong X, Qiao Q, Qian Z, Wei G. Recent computational studies of membrane interaction and disruption of human islet amyloid polypeptide: Monomers, oligomers and protofibrils. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2018. [PMID: 29530482 DOI: 10.1016/j.bbamem.2018.03.006] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The amyloid deposits of human islet amyloid polypeptide (hIAPP) are found in type 2 diabetes patients. hIAPP monomer is intrinsically disordered in solution, whereas it can form amyloid fibrils both in vivo and in vitro. Extensive evidence suggests that hIAPP causes the disruption of cellular membrane, and further induces cytotoxicity and the death of islet β-cells in pancreas. The presence of membrane also accelerates the hIAPP fibril formation. hIAPP oligomers and protofibrils in the early stage of aggregation were reported to be the most cytotoxic, disrupting the membrane integrity and giving rise to the pathological process. The detailed molecular mechanisms of hIAPP-membrane interactions and membrane disruption are complex and remain mostly unknown. Here in this review, we focus on recent computational studies that investigated the interactions of full length and fragmentary hIAPP monomers, oligomers and protofibrils with anionic, zwitterionic and mixed anionic-zwitterionic lipid bilayers. We mainly discuss the binding orientation of monomers at membrane surface, the conformational ensemble and the oligomerization of hIAPP inside membranes, the effect of lipid composition on hIAPP oligomers/protofibrils-membrane interactions, and the hIAPP-induced membrane perturbation. This review provides mechanistic insights into the interactions between hIAPP and lipid bilayers with different lipid composition at an atomistic level, which is helpful to understand the hIAPP cytotoxicity mediated by membrane. This article is part of a Special Issue entitled: Protein Aggregation and Misfolding at the Cell Membrane Interface edited by Ayyalusamy Ramamoorthy.
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Affiliation(s)
- Xuewei Dong
- Department of Physics, State Key Laboratory of Surface Physics, Key Laboratory for Computational Physical Science (Ministry of Education), Collaborative Innovation Center of Advanced Microstructures (Nanjing), Fudan University, Shanghai 200433, China
| | - Qin Qiao
- Digital Medical Research Center, School of Basic Medical Sciences, Fudan University, Shanghai 200032, China; Shanghai Key Laboratory of Medical Imaging Computing and Computer Assisted Intervention, Shanghai 200032, China.
| | - Zhenyu Qian
- Key Laboratory of Exercise and Health Sciences (Ministry of Education) and School of Kinesiology, Shanghai University of Sport, Shanghai 200438, China
| | - Guanghong Wei
- Department of Physics, State Key Laboratory of Surface Physics, Key Laboratory for Computational Physical Science (Ministry of Education), Collaborative Innovation Center of Advanced Microstructures (Nanjing), Fudan University, Shanghai 200433, China.
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82
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Amyloid growth and membrane damage: Current themes and emerging perspectives from theory and experiments on Aβ and hIAPP. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2018; 1860:1625-1638. [PMID: 29501606 DOI: 10.1016/j.bbamem.2018.02.022] [Citation(s) in RCA: 97] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Revised: 02/21/2018] [Accepted: 02/21/2018] [Indexed: 12/15/2022]
Abstract
Alzheimer's Disease (AD) and Type 2 diabetes mellitus (T2DM) are two incurable diseases both hallmarked by an abnormal deposition of the amyloidogenic peptides Aβ and Islet Amyloid Polypeptide (IAPP) in affected tissues. Epidemiological data demonstrate that patients suffering from diabetes are at high risk of developing AD, thus making the search for factors common to the two pathologies of special interest for the design of new therapies. Accumulating evidence suggests that the toxic properties of both Aβ or IAPP are ascribable to their ability to damage the cell membrane. However, the molecular details describing Aβ or IAPP interaction with membranes are poorly understood. This review focuses on biophysical and in silico studies addressing these topics. Effects of calcium, cholesterol and membrane lipid composition in driving aberrant Aβ or IAPP interaction with the membrane will be specifically considered. The cross correlation of all these factors appears to be a key issue not only to shed light in the countless and often controversial reports relative to this area but also to gain valuable insights into the central events leading to membrane damage caused by amyloidogenic peptides. This article is part of a Special Issue entitled: Protein Aggregation and Misfolding at the Cell Membrane Interface edited by Ayyalusamy Ramamoorthy.
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83
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Cheng B, Li Y, Ma L, Wang Z, Petersen RB, Zheng L, Chen Y, Huang K. Interaction between amyloidogenic proteins and biomembranes in protein misfolding diseases: Mechanisms, contributors, and therapy. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2018; 1860:1876-1888. [PMID: 29466701 DOI: 10.1016/j.bbamem.2018.02.013] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/30/2017] [Revised: 02/12/2018] [Accepted: 02/13/2018] [Indexed: 12/14/2022]
Abstract
The toxic deposition of misfolded amyloidogenic proteins is associated with more than fifty protein misfolding diseases (PMDs), including Alzheimer's disease, Parkinson's disease and type 2 diabetes mellitus. Protein deposition is a multi-step process modulated by a variety of factors, in particular by membrane-protein interaction. The interaction results in permeabilization of biomembranes contributing to the cytotoxicity that leads to PMDs. Different biological and physiochemical factors, such as protein sequence, lipid composition, and chaperones, are known to affect the membrane-protein interaction. Here, we provide a comprehensive review of the mechanisms and contributing factors of the interaction between biomembranes and amyloidogenic proteins, and a summary of the therapeutic approaches to PMDs that target this interaction. This article is part of a Special Issue entitled: Protein Aggregation and Misfolding at the Cell Membrane Interface edited by Ayyalusamy Ramamoorthy.
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Affiliation(s)
- Biao Cheng
- Department of Pharmacy, The Central Hospital of Wuhan, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430023, China; Key Laboratory for Molecular Diagnosis of Hubei Province, The Central Hospital of Wuhan, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430023, China
| | - Yang Li
- Tongji School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Liang Ma
- Tongji School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Zhuoyi Wang
- Tongji School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Robert B Petersen
- Foundational Sciences, Central Michigan University College of Medicine, Mt. Pleasant, MI 48858, USA
| | - Ling Zheng
- Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan 430072, China
| | - Yuchen Chen
- Tongji School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Kun Huang
- Tongji School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China.
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84
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Liu Y, Ren B, Zhang Y, Sun Y, Chang Y, Liang G, Xu L, Zheng J. Molecular simulation aspects of amyloid peptides at membrane interface. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2018; 1860:1906-1916. [PMID: 29421626 DOI: 10.1016/j.bbamem.2018.02.004] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2017] [Revised: 01/31/2018] [Accepted: 02/01/2018] [Indexed: 12/13/2022]
Abstract
The interactions of amyloid peptides with cell membranes play an important role in maintaining the integrity and functionality of cell membrane. A thorough molecular-level understanding of the structure, dynamics, and interactions between amyloid peptides and cell membranes is critical to amyloid aggregation and toxicity mechanisms for the bench-to-bedside applications. Here we review the most recent computational studies of amyloid peptides at model cell membranes. Different mechanisms of action of amyloid peptides on/in cell membranes, targeted by different computational techniques at different lengthscales and timescales, are rationally discussed. Finally, we have proposed some new insights into the remaining challenges and perspectives for future studies to improve our understanding of the activity of amyloid peptides associated with protein-misfolding diseases. This article is part of a Special Issue entitled: Protein Aggregation and Misfolding at the Cell Membrane Interface edited by Ayyalusamy Ramamoorthy.
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Affiliation(s)
- Yonglan Liu
- Hunan Key Laboratory of Biomedical Nanomaterials and Devices, College of Life Science and Chemistry, Hunan University of Technology, Zhuzhou 412007, PR China; Department of Chemical and Biomolecular Engineering, The University of Akron, Akron, OH 44325, United States
| | - Baiping Ren
- Department of Chemical and Biomolecular Engineering, The University of Akron, Akron, OH 44325, United States
| | - Yanxian Zhang
- Department of Chemical and Biomolecular Engineering, The University of Akron, Akron, OH 44325, United States
| | - Yan Sun
- Department of Biochemical Engineering and Key Laboratory of Systems Bioengineering of the Ministry of Education School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China
| | - Yung Chang
- R&D Center for Membrane Technology and Department of Chemical EngineeringChung Yuan Christian University, Chung-Li, Taoyuan 320, Taiwan
| | - Guizhao Liang
- Key Laboratory of Biorheological Science and Technology, Ministry of Education, Bioengineering College, Chongqing University, Chongqing 400044, PR China
| | - Lijian Xu
- Hunan Key Laboratory of Biomedical Nanomaterials and Devices, College of Life Science and Chemistry, Hunan University of Technology, Zhuzhou 412007, PR China; Department of Chemical and Biomolecular Engineering, The University of Akron, Akron, OH 44325, United States.
| | - Jie Zheng
- Department of Chemical and Biomolecular Engineering, The University of Akron, Akron, OH 44325, United States.
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85
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Fernández-Pérez EJ, Sepúlveda FJ, Peters C, Bascuñán D, Riffo-Lepe NO, González-Sanmiguel J, Sánchez SA, Peoples RW, Vicente B, Aguayo LG. Effect of Cholesterol on Membrane Fluidity and Association of Aβ Oligomers and Subsequent Neuronal Damage: A Double-Edged Sword. Front Aging Neurosci 2018. [PMID: 30123122 DOI: 10.3389/fnagi.2018.002.26] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/09/2023] Open
Abstract
Background: The beta-amyloid peptide (Aβ) involved in Alzheimer's disease (AD) has been described to associate/aggregate on the cell surface disrupting the membrane through pore formation and breakage. However, molecular determinants involved for this interaction (e.g., some physicochemical properties of the cell membrane) are largely unknown. Since cholesterol is an important molecule for membrane structure and fluidity, we examined the effect of varying cholesterol content with the association and membrane perforation by Aβ in cultured hippocampal neurons. Methods: To decrease or increase the levels of cholesterol in the membrane we used methyl-β-cyclodextrin (MβCD) and MβCD/cholesterol, respectively. We analyzed if membrane fluidity was affected using generalized polarization (GP) imaging and the fluorescent dye di-4-ANEPPDHQ. Additionally membrane association and perforation was assessed using immunocytochemistry and electrophysiological techniques, respectively. Results: The results showed that cholesterol removal decreased the macroscopic association of Aβ to neuronal membranes (fluorescent-puncta/20 μm: control = 18 ± 2 vs. MβCD = 10 ± 1, p < 0.05) and induced a facilitation of the membrane perforation by Aβ with respect to control cells (half-time for maximal charge transferred: control = 7.2 vs. MβCD = 4.4). Under this condition, we found an increase in membrane fluidity (46 ± 3.3% decrease in GP value, p < 0.001). On the contrary, increasing cholesterol levels incremented membrane rigidity (38 ± 2.7% increase in GP value, p < 0.001) and enhanced the association and clustering of Aβ (fluorescent-puncta/20 μm: control = 18 ± 2 vs. MβCD = 10 ± 1, p < 0.01), but inhibited membrane disruption. Conclusion: Our results strongly support the significance of plasma membrane organization in the toxic effects of Aβ in hippocampal neurons, since fluidity can regulate distribution and insertion of the Aβ peptide in the neuronal membrane.
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Affiliation(s)
- Eduardo J Fernández-Pérez
- Laboratory of Neurophysiology, Department of Physiology, Universidad de Concepción, Concepción, Chile
| | - Fernando J Sepúlveda
- Laboratory of Neurophysiology, Department of Physiology, Universidad de Concepción, Concepción, Chile
| | - Christian Peters
- Laboratory of Neurophysiology, Department of Physiology, Universidad de Concepción, Concepción, Chile
| | - Denisse Bascuñán
- Laboratory of Neurophysiology, Department of Physiology, Universidad de Concepción, Concepción, Chile
| | - Nicolás O Riffo-Lepe
- Laboratory of Neurophysiology, Department of Physiology, Universidad de Concepción, Concepción, Chile
| | | | - Susana A Sánchez
- Departamento de Polímeros, Facultad de Ciencias Químicas, Universidad de Concepción, Concepción, Chile
| | - Robert W Peoples
- Department of Biomedical Sciences, Marquette University, Milwaukee, WI, United States
| | - Benjamín Vicente
- Department of Psychiatry and Mental Health, Universidad de Concepción, Concepción, Chile
| | - Luis G Aguayo
- Laboratory of Neurophysiology, Department of Physiology, Universidad de Concepción, Concepción, Chile
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86
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Stewart BD, Scott CE, McCoy TP, Yin G, Despa F, Despa S, Kekenes-Huskey PM. Computational modeling of amylin-induced calcium dysregulation in rat ventricular cardiomyocytes. Cell Calcium 2017; 71:65-74. [PMID: 29604965 DOI: 10.1016/j.ceca.2017.11.006] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2017] [Revised: 11/30/2017] [Accepted: 11/30/2017] [Indexed: 01/08/2023]
Abstract
Hyperamylinemia is a condition that accompanies obesity and precedes type II diabetes, and it is characterized by above-normal blood levels of amylin, the pancreas-derived peptide. Human amylin oligomerizes easily and can deposit in the pancreas [1], brain [2], and heart [3], where they have been associated with calcium dysregulation. In the heart, accumulating evidence suggests that human amylin oligomers form moderately cation-selective [4,5] channels that embed in the cell sarcolemma (SL). The oligomers increase membrane conductance in a concentration-dependent manner [5], which is correlated with elevated cytosolic Ca2+. These findings motivate our core hypothesis that non-selective inward Ca2+ conduction afforded by human amylin oligomers increase cytosolic and sarcoplasmic reticulum (SR) Ca2+ load, which thereby magnifies intracellular Ca2+ transients. Questions remain however regarding the mechanism of amylin-induced Ca2+ dysregulation, including whether enhanced SL Ca2+ influx is sufficient to elevate cytosolic Ca2+ load [6], and if so, how might amplified Ca2+ transients perturb Ca2+-dependent cardiac pathways. To investigate these questions, we modified a computational model of cardiomyocytes Ca2+ signaling to reflect experimentally-measured changes in SL membrane permeation and decreased sarcoplasmic/endoplasmic reticulum calcium ATPase (SERCA) function stemming from acute and transgenic human amylin peptide exposure. With this model, we confirmed the hypothesis that increasing SL permeation alone was sufficient to enhance Ca2+ transient amplitudes. Our model indicated that amplified cytosolic transients are driven by increased Ca2+ loading of the SR and that greater fractional release may contribute to the Ca2+-dependent activation of calmodulin, which could prime the activation of myocyte remodeling pathways. Importantly, elevated Ca2+ in the SR and dyadic space collectively drive greater fractional SR Ca2+ release for human amylin expressing rats (HIP) and acute amylin-exposed rats (+Amylin) mice, which contributes to the inotropic rise in cytosolic Ca2+ transients. These findings suggest that increased membrane permeation induced by oligomeratization of amylin peptide in cell sarcolemma contributes to Ca2+ dysregulation in pre-diabetes.
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Affiliation(s)
- Bradley D Stewart
- Department of Chemistry, University of Kentucky, 505 Rose St. Chemistry-Physics Building, Lexington, KY 40506, USA
| | - Caitlin E Scott
- Department of Chemistry, University of Kentucky, 505 Rose St. Chemistry-Physics Building, Lexington, KY 40506, USA
| | - Thomas P McCoy
- Department of Family & Community Nursing, University of North Carolina - Greensboro, 1008 Administration Dr. McIver Building, Greensboro, NC 27412, USA
| | - Guo Yin
- Department of Pharmacology and Nutritional Sciences, University of Kentucky, UK Medical Center, MN 150, Lexington, KY 40536, USA
| | - Florin Despa
- Department of Pharmacology and Nutritional Sciences, University of Kentucky, UK Medical Center, MN 150, Lexington, KY 40536, USA
| | - Sanda Despa
- Department of Pharmacology and Nutritional Sciences, University of Kentucky, UK Medical Center, MN 150, Lexington, KY 40536, USA.
| | - Peter M Kekenes-Huskey
- Department of Chemistry, University of Kentucky, 505 Rose St. Chemistry-Physics Building, Lexington, KY 40506, USA.
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87
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Recombinant human islet amyloid polypeptide forms shorter fibrils and mediates β-cell apoptosis via generation of oxidative stress. Biochem J 2017; 474:3915-3934. [DOI: 10.1042/bcj20170323] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2017] [Revised: 10/09/2017] [Accepted: 10/11/2017] [Indexed: 02/08/2023]
Abstract
Protein misfolding and aggregation play an important role in many human diseases including Alzheimer's, Parkinson's and type 2 diabetes mellitus (T2DM). The human islet amyloid polypeptide (hIAPP) forms amyloid plaques in the pancreas of T2DM subjects (>95%) that are involved in deteriorating islet function and in mediating β-cell apoptosis. However, the detailed mechanism of action, structure and nature of toxic hIAPP species responsible for this effect remains elusive to date mainly due to the high cost associated with the chemical synthesis of pure peptide required for these studies. In the present work, we attempted to obtain structural and mechanistic insights into the hIAPP aggregation process using recombinant hIAPP (rhIAPP) isolated from Escherichia coli. Results from biophysical and structural studies indicate that the rhIAPP self-assembled into highly pure, β-sheet-rich amyloid fibrils with uniform morphology. rhIAPP-mediated apoptosis in INS-1E cells was associated with increased oxidative stress and changes in mitochondrial membrane potential. The transcript levels of apoptotic genes - Caspase-3 and Bax were found to be up-regulated, while the levels of the anti-apoptotic gene - Bcl2 were down-regulated in rhIAPP-treated cells. Additionally, the expression levels of genes involved in combating oxidative stress namely Catalase, SOD1 and GPx were down-regulated. rhIAPP exposure also affected glucose-stimulated insulin secretion from isolated pancreatic islets. The aggregation of rhIAPP also occurred significantly faster when compared with that of the chemically synthesized peptide. We also show that the rhIAPP fibrils were shorter and more cytotoxic. In summary, our study is one among the few to provide comprehensive evaluation of structural, biophysical and cytotoxic properties of rhIAPP.
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88
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Ke PC, Sani MA, Ding F, Kakinen A, Javed I, Separovic F, Davis TP, Mezzenga R. Implications of peptide assemblies in amyloid diseases. Chem Soc Rev 2017; 46:6492-6531. [PMID: 28702523 PMCID: PMC5902192 DOI: 10.1039/c7cs00372b] [Citation(s) in RCA: 239] [Impact Index Per Article: 34.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Neurodegenerative disorders and type 2 diabetes are global epidemics compromising the quality of life of millions worldwide, with profound social and economic implications. Despite the significant differences in pathology - much of which are poorly understood - these diseases are commonly characterized by the presence of cross-β amyloid fibrils as well as the loss of neuronal or pancreatic β-cells. In this review, we document research progress on the molecular and mesoscopic self-assembly of amyloid-beta, alpha synuclein, human islet amyloid polypeptide and prions, the peptides and proteins associated with Alzheimer's, Parkinson's, type 2 diabetes and prion diseases. In addition, we discuss the toxicities of these amyloid proteins based on their self-assembly as well as their interactions with membranes, metal ions, small molecules and engineered nanoparticles. Through this presentation we show the remarkable similarities and differences in the structural transitions of the amyloid proteins through primary and secondary nucleation, the common evolution from disordered monomers to alpha-helices and then to β-sheets when the proteins encounter the cell membrane, and, the consensus (with a few exceptions) that off-pathway oligomers, rather than amyloid fibrils, are the toxic species regardless of the pathogenic protein sequence or physicochemical properties. In addition, we highlight the crucial role of molecular self-assembly in eliciting the biological and pathological consequences of the amyloid proteins within the context of their cellular environments and their spreading between cells and organs. Exploiting such structure-function-toxicity relationship may prove pivotal for the detection and mitigation of amyloid diseases.
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Affiliation(s)
- Pu Chun Ke
- ARC Center of Excellence in Convergent Bio-Nano Science and Technology, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, VIC 3052, Australia
| | - Marc-Antonie Sani
- School of Chemistry, Bio21 Institute, The University of Melbourne, 30 Flemington Rd, Parkville, VIC 3010, Australia
| | - Feng Ding
- Department of Physics and Astronomy, Clemson University, Clemson, SC 29634, United States
| | - Aleksandr Kakinen
- ARC Center of Excellence in Convergent Bio-Nano Science and Technology, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, VIC 3052, Australia
| | - Ibrahim Javed
- ARC Center of Excellence in Convergent Bio-Nano Science and Technology, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, VIC 3052, Australia
| | - Frances Separovic
- School of Chemistry, Bio21 Institute, The University of Melbourne, 30 Flemington Rd, Parkville, VIC 3010, Australia
| | - Thomas P. Davis
- ARC Center of Excellence in Convergent Bio-Nano Science and Technology, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, VIC 3052, Australia
- Department of Chemistry, University of Warwick, Gibbet Hill, Coventry, CV4 7AL, United Kingdom
| | - Raffaele Mezzenga
- ETH Zurich, Department of Health Science & Technology, Schmelzbergstrasse 9, LFO, E23, 8092 Zurich, Switzerland
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89
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Raleigh D, Zhang X, Hastoy B, Clark A. The β-cell assassin: IAPP cytotoxicity. J Mol Endocrinol 2017; 59:R121-R140. [PMID: 28811318 DOI: 10.1530/jme-17-0105] [Citation(s) in RCA: 93] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/02/2017] [Accepted: 08/15/2017] [Indexed: 12/28/2022]
Abstract
Islet amyloid polypeptide (IAPP) forms cytotoxic oligomers and amyloid fibrils in islets in type 2 diabetes (T2DM). The causal factors for amyloid formation are largely unknown. Mechanisms of molecular folding and assembly of human IAPP (hIAPP) into β-sheets, oligomers and fibrils have been assessed by detailed biophysical studies of hIAPP and non-fibrillogenic, rodent IAPP (rIAPP); cytotoxicity is associated with the early phases (oligomers/multimers) of fibrillogenesis. Interaction with synthetic membranes promotes β-sheet assembly possibly via a transient α-helical molecular conformation. Cellular hIAPP cytotoxicity can be activated from intracellular or extracellular sites. In transgenic rodents overexpressing hIAPP, intracellular pro-apoptotic signals can be generated at different points in β-cell protein synthesis. Increased cellular trafficking of proIAPP, failure of the unfolded protein response (UPR) or excess trafficking of misfolded peptide via the degradation pathways can induce apoptosis; these data indicate that defects in intracellular handling of hIAPP can induce cytotoxicity. However, there is no evidence for IAPP overexpression in T2DM. Extracellular amyloidosis is directly related to the degree of β-cell apoptosis in islets in T2DM. IAPP fragments, fibrils and multimers interact with membranes causing disruption in vivo and in vitro These findings support a role for extracellular IAPP in β-sheet conformation in cytotoxicity. Inhibitors of fibrillogenesis are useful tools to determine the aberrant mechanisms that result in hIAPP molecular refolding and islet amyloidosis. However, currently, their role as therapeutic agents remains uncertain.
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Affiliation(s)
- Daniel Raleigh
- Department of ChemistryStony Brook University, Stony Brook, New York, USA
- Research Department of Structural and Molecule BiologyUniversity College London, London, UK
| | - Xiaoxue Zhang
- Department of ChemistryStony Brook University, Stony Brook, New York, USA
| | - Benoît Hastoy
- Oxford Centre for Diabetes Endocrinology and MetabolismUniversity of Oxford, Oxford, UK
| | - Anne Clark
- Oxford Centre for Diabetes Endocrinology and MetabolismUniversity of Oxford, Oxford, UK
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90
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Dignon GL, Zerze GH, Mittal J. Interplay Between Membrane Composition and Structural Stability of Membrane-Bound hIAPP. J Phys Chem B 2017; 121:8661-8668. [DOI: 10.1021/acs.jpcb.7b05689] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Gregory L. Dignon
- Department of Chemical and Biomolecular
Engineering, Lehigh University, Bethlehem, Pennsylvania 18015, United States
| | - Gül H. Zerze
- Department of Chemical and Biomolecular
Engineering, Lehigh University, Bethlehem, Pennsylvania 18015, United States
| | - Jeetain Mittal
- Department of Chemical and Biomolecular
Engineering, Lehigh University, Bethlehem, Pennsylvania 18015, United States
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91
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Christensen M, Skeby KK, Schiøtt B. Identification of Key Interactions in the Initial Self-Assembly of Amylin in a Membrane Environment. Biochemistry 2017; 56:4884-4894. [PMID: 28786287 DOI: 10.1021/acs.biochem.7b00344] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Islet amyloid polypeptide, also known as amylin, forms aggregates that reduce the amount of insulin-producing cells in patients with type II diabetes mellitus. Much remains unknown about the process of aggregation and cytotoxicity, but it is known that certain cell membrane components can alter the rate of aggregation. Using atomistic molecular dynamics simulations combined with the highly mobile membrane mimetic model incorporating enhanced sampling of lipid diffusion, we investigate interaction of amylin peptides with the membrane components as well as the self-assembly of amylin. Consistent with experimental evidence, we find that an initial membrane-bound α-helical state folds into stable β-sheet structures upon self-assembly. Our results suggest the following mechanism for the initial phase of amylin self-assembly. The peptides move around on the membrane with the positively charged N-terminus interacting with the negatively charged lipid headgroups. When the peptides start to interact, they partly unfold and break some of the contacts with the membrane. The initial interactions between the peptides are dominated by aromatic and hydrophobic interactions. Oligomers are formed showing both intra- and interpeptide β-sheets, initially with interactions mainly in the C-terminal domain of the peptides. Decreasing the pH to 5.5 is known to inhibit amyloid formation. At low pH, His18 is protonated, adding a fourth positive charge at the peptide. With His18 protonated, no oligomerization is observed in the simulations. The additional charge gives a strong midpoint anchoring of the peptides to negatively charged membrane components, and the peptides experience additional interpeptide repulsion, thereby preventing interactions.
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Affiliation(s)
- Mikkel Christensen
- Interdisciplinary Nanoscience Center (iNANO) and Department of Chemistry, Aarhus University , DK-8000 Aarhus, Denmark.,Sino-Danish Center for Education and Research , Beijing, China
| | - Katrine K Skeby
- Interdisciplinary Nanoscience Center (iNANO) and Department of Chemistry, Aarhus University , DK-8000 Aarhus, Denmark
| | - Birgit Schiøtt
- Interdisciplinary Nanoscience Center (iNANO) and Department of Chemistry, Aarhus University , DK-8000 Aarhus, Denmark
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92
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Structural Properties of Human IAPP Dimer in Membrane Environment Studied by All-Atom Molecular Dynamics Simulations. Sci Rep 2017; 7:7915. [PMID: 28801684 PMCID: PMC5554177 DOI: 10.1038/s41598-017-08504-x] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2017] [Accepted: 07/12/2017] [Indexed: 12/27/2022] Open
Abstract
The aggregation of human islet amyloid polypeptide (hIAPP) can damage the membrane of the β-cells in the pancreatic islets and induce type 2 diabetes (T2D). Growing evidences indicated that the major toxic species are small oligomers of IAPP. Due to the fast aggregation nature, it is hard to characterize the structures of IAPP oligomers by experiments, especially in the complex membrane environment. On the other side, molecular dynamics simulation can provide atomic details of the structure and dynamics of the aggregation of IAPP. In this study, all-atom bias-exchange metadynamics (BE-Meta) and unbiased molecular dynamics simulations were employed to study the structural properties of IAPP dimer in the membranes environments. A number of intermediates, including α-helical states, β-sheet states, and fully disordered states, are identified. The formation of N-terminal β-sheet structure is prior to the C-terminal β-sheet structure towards the final fibril-like structures. The α-helical intermediates have lower propensity in the dimeric hIAPP and are off-pathway intermediates. The simulations also demonstrate that the β-sheet intermediates induce more perturbation on the membrane than the α-helical and disordered states and thus pose higher disruption ability.
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93
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Dharmadana D, Reynolds NP, Conn CE, Valéry C. Molecular interactions of amyloid nanofibrils with biological aggregation modifiers: implications for cytotoxicity mechanisms and biomaterial design. Interface Focus 2017; 7:20160160. [PMID: 28630679 PMCID: PMC5474041 DOI: 10.1098/rsfs.2016.0160] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Amyloid nanofibrils are ubiquitous biological protein fibrous aggregates, with a wide range of either toxic or beneficial activities that are relevant to human disease and normal biology. Protein amyloid fibrillization occurs via nucleated polymerization, through non-covalent interactions. As such, protein nanofibril formation is based on a complex interplay between kinetic and thermodynamic factors. The process entails metastable oligomeric species and a highly thermodynamically favoured end state. The kinetics, and the reaction pathway itself, can be influenced by third party moieties, either molecules or surfaces. Specifically, in the biological context, different classes of biomolecules are known to act as catalysts, inhibitors or modifiers of the generic protein fibrillization process. The biological aggregation modifiers reviewed here include lipid membranes of varying composition, glycosaminoglycans and metal ions, with a final word on xenobiotic compounds. The corresponding molecular interactions are critically analysed and placed in the context of the mechanisms of cytotoxicity of the amyloids involved in diverse pathologies and the non-toxicity of functional amyloids (at least towards their biological host). Finally, the utilization of this knowledge towards the design of bio-inspired and biocompatible nanomaterials is explored.
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Affiliation(s)
- Durga Dharmadana
- School of Health and Biomedical Sciences, Discipline of Pharmaceutical Sciences, RMIT University, Bundoora, Melbourne, Victoria 3083, Australia
- School of Science, College of Science, Engineering and Health, RMIT University, Melbourne, Victoria 3001, Australia
| | - Nicholas P. Reynolds
- ARC Training Centre for Biodevices, Faculty of Science, Engineering and Technology, Swinburne University of Technology, Melbourne, Victoria 3122, Australia
| | - Charlotte E. Conn
- School of Science, College of Science, Engineering and Health, RMIT University, Melbourne, Victoria 3001, Australia
| | - Céline Valéry
- School of Health and Biomedical Sciences, Discipline of Pharmaceutical Sciences, RMIT University, Bundoora, Melbourne, Victoria 3083, Australia
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94
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Sequeira IR, Poppitt SD. Unfolding Novel Mechanisms of Polyphenol Flavonoids for Better Glycaemic Control: Targeting Pancreatic Islet Amyloid Polypeptide (IAPP). Nutrients 2017; 9:E788. [PMID: 28754022 PMCID: PMC5537902 DOI: 10.3390/nu9070788] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2017] [Revised: 07/12/2017] [Accepted: 07/18/2017] [Indexed: 12/17/2022] Open
Abstract
Type 2 diabetes (T2D) is characterised by hyperglycaemia resulting from defective insulin secretion, insulin resistance, or both. The impact of over-nutrition and reduced physical activity, evidenced by the exponential rise in obesity and the prevalence of T2D, strongly supports the implementation of lifestyle modification programs. Accordingly, an increased consumption of fruits and plant-derived foods has been advocated, as their intake is inversely correlated with T2D prevalence; this has been attributed, in part, to their contained polyphenolic compounds. Over the last decade, a body of work has focussed on establishing the mechanisms by which polyphenolic compounds exert beneficial effects to limit carbohydrate digestion, enhance insulin-mediated glucose uptake, down-regulate hepatic gluconeogenesis and decrease oxidative stress; the latter anti-oxidative property being the most documented. Novel effects on the inhibition of glucocorticoid action and the suppression of amylin misfolding and aggregation have been identified more recently. Amyloid fibrils form from spontaneously misfolded amylin, depositing in islet cells to elicit apoptosis, beta cell degeneration and decrease insulin secretion, with amyloidosis affecting up to 80% of pancreatic islet cells in T2D. Therefore, intervening with polyphenolic compounds offers a novel approach to suppressing risk or progression to T2D. This review gives an update on the emerging mechanisms related to dietary polyphenol intake for the maintenance of glycaemic control and the prevention of T2D.
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Affiliation(s)
- Ivana R Sequeira
- Human Nutrition Unit, School of Biological Sciences, University of Auckland, Auckland 1010, New Zealand.
- High-Value Nutrition National Science Challenge, Auckland 1142, New Zealand.
| | - Sally D Poppitt
- Human Nutrition Unit, School of Biological Sciences, University of Auckland, Auckland 1010, New Zealand.
- High-Value Nutrition National Science Challenge, Auckland 1142, New Zealand.
- Department of Medicine, University of Auckland, Auckland 1142, New Zealand.
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95
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Sciacca MFM, Lolicato F, Di Mauro G, Milardi D, D'Urso L, Satriano C, Ramamoorthy A, La Rosa C. The Role of Cholesterol in Driving IAPP-Membrane Interactions. Biophys J 2017; 111:140-51. [PMID: 27410742 DOI: 10.1016/j.bpj.2016.05.050] [Citation(s) in RCA: 73] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2016] [Revised: 05/15/2016] [Accepted: 05/26/2016] [Indexed: 01/01/2023] Open
Abstract
Our knowledge of the molecular events underlying type 2 diabetes mellitus-a protein conformational disease characterized by the aggregation of islet amyloid polypeptide (IAPP) in pancreatic β cells-is limited. However, amyloid-mediated membrane damage is known to play a key role in IAPP cytotoxicity, and therefore the effects of lipid composition on modulating IAPP-membrane interactions have been the focus of intense research. In particular, membrane cholesterol content varies with aging and consequently with adverse environmental factors such as diet and lifestyle, but its role in the development of the disease is controversial. In this study, we employ a combination of experimental techniques and in silico molecular simulations to shed light on the role of cholesterol in IAPP aggregation and the related membrane disruption. We show that if anionic POPC/POPS vesicles are used as model membranes, cholesterol has a negligible effect on the kinetics of IAPP fibril growth on the surface of the bilayer. In addition, cholesterol inhibits membrane damage by amyloid-induced poration on membranes, but enhances leakage through fiber growth on the membrane surface. Conversely, if 1:2 DOPC/DPPC raft-like model membranes are used, cholesterol accelerates fiber growth. Next, it enhances pore formation and suppresses fiber growth on the membrane surface, leading to leakage. Our results highlight a twofold effect of cholesterol on the amyloidogenicity of IAPP and help explain its debated role in type 2 diabetes mellitus.
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Affiliation(s)
- Michele F M Sciacca
- Istituto di Biostrutture e Bioimmagini, Consiglio Nazionale delle Ricerche, Catania, Italy
| | - Fabio Lolicato
- Dipartimento di Scienze Chimiche, Università degli Studi di Catania, Catania, Italy; Department of Physics, Tampere University of Technology, Tampere, Finland
| | - Giacomo Di Mauro
- Dipartimento di Scienze Chimiche, Università degli Studi di Catania, Catania, Italy
| | - Danilo Milardi
- Istituto di Biostrutture e Bioimmagini, Consiglio Nazionale delle Ricerche, Catania, Italy
| | - Luisa D'Urso
- Dipartimento di Scienze Chimiche, Università degli Studi di Catania, Catania, Italy
| | - Cristina Satriano
- Dipartimento di Scienze Chimiche, Università degli Studi di Catania, Catania, Italy
| | - Ayyalusamy Ramamoorthy
- Biophysics, University of Michigan, Ann Arbor, Michigan; Department of Chemistry, University of Michigan, Ann Arbor, Michigan; Institute for Advanced Study, Technische Universität München, Lichtenbergstrasse, Garching, Germany.
| | - Carmelo La Rosa
- Dipartimento di Scienze Chimiche, Università degli Studi di Catania, Catania, Italy.
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96
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Zhang Y, Song W. Islet amyloid polypeptide: Another key molecule in Alzheimer's pathogenesis? Prog Neurobiol 2017; 153:100-120. [PMID: 28274676 DOI: 10.1016/j.pneurobio.2017.03.001] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2016] [Revised: 02/17/2017] [Accepted: 03/02/2017] [Indexed: 12/14/2022]
Abstract
Recent epidemiological evidence reveals that patients suffering from type 2 diabetes mellitus (T2DM) often experience a significant decline in cognitive function, and approximately 70% of those cases eventually develop Alzheimer's disease (AD). Although several pathological processes are shared by AD and T2DM, the exact molecular mechanisms connecting these two diseases are poorly understood. Aggregation of human islet amyloid polypeptide (hIAPP), the pathological hallmark of T2DM, has also been detected in brain tissue and is associated with cognitive decline and AD development. In addition, hIAPP and amyloid β protein (Aβ) share many biophysical and physiological properties as well as exert similar cytotoxic mechanisms. Therefore, it is important to examine the possible role of hIAPP in the pathogenesis of AD. In this article, we introduce the basics on this amyloidogenic protein. More importantly, we discuss the potential mechanisms of hIAPP-induced AD development, which will be beneficial for proposing novel and feasible strategies to optimize AD prevention and/or treatment in diabetics.
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Affiliation(s)
- Yun Zhang
- Townsend Family Laboratories, Department of Psychiatry, The University of British Columbia, 2255 Wesbrook Mall, Vancouver, BC V6T 1Z3, Canada
| | - Weihong Song
- Townsend Family Laboratories, Department of Psychiatry, The University of British Columbia, 2255 Wesbrook Mall, Vancouver, BC V6T 1Z3, Canada.
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97
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Wang ST, Lin Y, Todorova N, Xu Y, Mazo M, Rana S, Leonardo V, Amdursky N, Spicer CD, Alexander BD, Edwards AA, Matthews SJ, Yarovsky I, Stevens MM. Facet-Dependent Interactions of Islet Amyloid Polypeptide with Gold Nanoparticles: Implications for Fibril Formation and Peptide-Induced Lipid Membrane Disruption. CHEMISTRY OF MATERIALS : A PUBLICATION OF THE AMERICAN CHEMICAL SOCIETY 2017; 29:1550-1560. [PMID: 28260837 PMCID: PMC5333186 DOI: 10.1021/acs.chemmater.6b04144] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2016] [Revised: 01/25/2017] [Indexed: 05/03/2023]
Abstract
A comprehensive understanding of the mechanisms of interaction between proteins or peptides and nanomaterials is crucial for the development of nanomaterial-based diagnostics and therapeutics. In this work, we systematically explored the interactions between citrate-capped gold nanoparticles (AuNPs) and islet amyloid polypeptide (IAPP), a 37-amino acid peptide hormone co-secreted with insulin from the pancreatic islet. We utilized diffusion-ordered spectroscopy, isothermal titration calorimetry, localized surface plasmon resonance spectroscopy, gel electrophoresis, atomic force microscopy, transmission electron microscopy (TEM), and molecular dynamics (MD) simulations to systematically elucidate the underlying mechanism of the IAPP-AuNP interactions. Because of the presence of a metal-binding sequence motif in the hydrophilic peptide domain, IAPP strongly interacts with the Au surface in both the monomeric and fibrillar states. Circular dichroism showed that AuNPs triggered the IAPP conformational transition from random coil to ordered structures (α-helix and β-sheet), and TEM imaging suggested the acceleration of IAPP fibrillation in the presence of AuNPs. MD simulations revealed that the IAPP-AuNP interactions were initiated by the N-terminal domain (IAPP residues 1-19), which subsequently induced a facet-dependent conformational change in IAPP. On a Au(111) surface, IAPP was unfolded and adsorbed directly onto the Au surface, while for the Au(100) surface, it interacted predominantly with the citrate adlayer and retained some helical conformation. The observed affinity of AuNPs for IAPP was further applied to reduce the level of peptide-induced lipid membrane disruption.
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Affiliation(s)
- Shih-Ting Wang
- Department
of Materials, Imperial College London, London SW7 2AZ, U.K.
- Department
of Bioengineering and Institute of Biomedical Engineering, Imperial College London, London SW7 2AZ, U.K.
| | - Yiyang Lin
- Department
of Materials, Imperial College London, London SW7 2AZ, U.K.
- Department
of Bioengineering and Institute of Biomedical Engineering, Imperial College London, London SW7 2AZ, U.K.
| | - Nevena Todorova
- School
of Engineering, RMIT University, GPO Box 2476, Melbourne, Victoria 3001, Australia
| | - Yingqi Xu
- Department
of Life Sciences, Imperial College London, London SW7 2AZ, U.K.
| | - Manuel Mazo
- Department
of Materials, Imperial College London, London SW7 2AZ, U.K.
- Department
of Bioengineering and Institute of Biomedical Engineering, Imperial College London, London SW7 2AZ, U.K.
| | - Subinoy Rana
- Department
of Materials, Imperial College London, London SW7 2AZ, U.K.
- Department
of Bioengineering and Institute of Biomedical Engineering, Imperial College London, London SW7 2AZ, U.K.
| | - Vincent Leonardo
- Department
of Materials, Imperial College London, London SW7 2AZ, U.K.
- Department
of Bioengineering and Institute of Biomedical Engineering, Imperial College London, London SW7 2AZ, U.K.
| | - Nadav Amdursky
- Department
of Materials, Imperial College London, London SW7 2AZ, U.K.
- Department
of Bioengineering and Institute of Biomedical Engineering, Imperial College London, London SW7 2AZ, U.K.
| | - Christopher D. Spicer
- Department
of Materials, Imperial College London, London SW7 2AZ, U.K.
- Department
of Bioengineering and Institute of Biomedical Engineering, Imperial College London, London SW7 2AZ, U.K.
| | - Bruce D. Alexander
- Department
of Pharmaceutical, Chemical and Environmental Science, University of Greenwich, Central Avenue, Chatham, Kent ME4 4TB, U.K.
| | - Alison A. Edwards
- Medway School
of Pharmacy, Universities of Kent and Greenwich
at Medway, Central Avenue, Chatham, Kent ME4 4TB, U.K.
| | - Steve J. Matthews
- Department
of Life Sciences, Imperial College London, London SW7 2AZ, U.K.
| | - Irene Yarovsky
- School
of Engineering, RMIT University, GPO Box 2476, Melbourne, Victoria 3001, Australia
| | - Molly M. Stevens
- Department
of Materials, Imperial College London, London SW7 2AZ, U.K.
- Department
of Bioengineering and Institute of Biomedical Engineering, Imperial College London, London SW7 2AZ, U.K.
- E-mail:
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98
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Zhang X, St Clair JR, London E, Raleigh DP. Islet Amyloid Polypeptide Membrane Interactions: Effects of Membrane Composition. Biochemistry 2017; 56:376-390. [PMID: 28054763 DOI: 10.1021/acs.biochem.6b01016] [Citation(s) in RCA: 100] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Amyloid formation by islet amyloid polypeptide (IAPP) contributes to β-cell dysfunction in type 2 diabetes. Perturbation of the β-cell membrane may contribute to IAPP-induced toxicity. We examine the effects of lipid composition, salt, and buffer on IAPP amyloid formation and on the ability of IAPP to induce leakage of model membranes. Even low levels of anionic lipids promote amyloid formation and membrane permeabilization. Increasing the percentage of the anionic lipids, 1-palmitoyl-2-oleoyl-sn-glycero-3-phospho-l-serine (POPS) or 1,2-dioleoyl-sn-glycero-3-phospho(1'-rac-glycerol), enhances the rate of amyloid formation and increases the level of membrane permeabilization. The choice of zwitterionic lipid has no noticeable effect on membrane-catalyzed amyloid formation but in most cases affects leakage, which tends to decrease in the following order: 1,2-dioleoyl-sn-glycero-3-phosphocholine > 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine > sphingomyelin. Uncharged lipids that increase the level of membrane order weaken the ability of IAPP to induce leakage. Leakage is due predominately to pore formation rather than complete disruption of the vesicles under the conditions used in these studies. Cholesterol at or below physiological levels significantly reduces the rate of vesicle-catalyzed IAPP amyloid formation and decreases the susceptibility to IAPP-induced leakage. The effects of cholesterol on amyloid formation are masked by 25 mol % POPS. Overall, there is a strong inverse correlation between the time to form amyloid and the extent of vesicle leakage. NaCl reduces the rate of membrane-catalyzed amyloid formation by anionic vesicles, but accelerates amyloid formation in solution. The implications for IAPP membrane interactions are discussed, as is the possibility that the loss of phosphatidylserine asymmetry enhances IAPP amyloid formation and membrane damage in vivo via a positive feedback loop.
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Affiliation(s)
- Xiaoxue Zhang
- Department of Chemistry, Stony Brook University , Stony Brook, New York 11794-3400, United States
| | - Johnna R St Clair
- Department of Biochemistry and Cell Biology, Stony Brook University , Stony Brook, New York 11794-5215, United States
| | - Erwin London
- Department of Chemistry, Stony Brook University , Stony Brook, New York 11794-3400, United States.,Department of Biochemistry and Cell Biology, Stony Brook University , Stony Brook, New York 11794-5215, United States
| | - Daniel P Raleigh
- Department of Chemistry, Stony Brook University , Stony Brook, New York 11794-3400, United States.,Graduate Program in Biochemistry and Structural Biology, Stony Brook University , Stony Brook, New York 11794-5215, United States
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99
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Guardado-Mendoza R, Chávez AO, Jiménez-Ceja LM, Hansis-Diarte A, DeFronzo RA, Folli F, Tripathy D. Islet amyloid polypeptide response to maximal hyperglycemia and arginine is altered in impaired glucose tolerance and type 2 diabetes mellitus. Acta Diabetol 2017; 54:53-61. [PMID: 27624579 DOI: 10.1007/s00592-016-0904-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/15/2016] [Accepted: 08/18/2016] [Indexed: 12/29/2022]
Abstract
AIMS Pancreatic islet amyloid deposition is a characteristic feature of type 2 diabetes mellitus (T2DM). Islet amyloid polypeptide (IAPP) is co-secreted with insulin, but its secretion profile and relationship to insulin and C-peptide in response to glucose and non-glucose stimuli has not been clearly defined. METHODS Forty subjects (13 NGT, 12 IGT and 15 T2DM) participated in an OGTT and two-step hyperglycemic (225 and 400 mg/dl) clamp (80 min/step) followed by an IV arginine bolus. Acute insulin (AIR), C-peptide (ACPR) and IAPP (AIAR) responses during each hyperglycemic step and following arginine (AIRArg) were assessed. RESULTS AIR and ACPR during both hyperglycemic steps and after arginine progressively decreased from NGT to IGT to T2DM. Fasting IAPP concentrations were higher in T2DM compared to NGT and IGT subjects. The acute IAPP0-10 was markedly decreased only in T2DM, while the acute IAPP80-90 response during the second step (80-160 min) of hyperglycemic clamp and in response to arginine was markedly impaired in both IGT and T2DM. The ratio of IAPP/C-peptide during the first (225 mg/dl) and second step (400 mg/dl), and in response to arginine, was decreased in T2DM versus both NGT and IGT (p < 0.01). The acute IAPP0-10 correlated with ACPR0-10 (r = 0.665, p < 0.001) and AIR0-10 (r = 0.543, p < 0.001). CONCLUSIONS Basal IAPP secretion is higher in T2DM and IGT versus NGT but is reduced in response to hyperglycemia and arginine. The IAPP/C-peptide ratio is reduced with prolonged and more severe hyperglycemia in T2DM individuals. CLINICAL TRIAL REGISTRATION NCT00845182.
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Affiliation(s)
- Rodolfo Guardado-Mendoza
- Diabetes Division, University of Texas Health Science Center at San Antonio, 7703 Floyd Curl Drive, San Antonio, 78229, TX, USA
- Division of Health Sciences, Department of Medicine and Nutrition, University of Guanajuato, Guanajuato, Mexico
- Departamento de Investigación, Hospital Regional de Alta Especialidad del Bajío, Guanajuato, Mexico
| | - Alberto O Chávez
- Diabetes Division, University of Texas Health Science Center at San Antonio, 7703 Floyd Curl Drive, San Antonio, 78229, TX, USA
| | - Lilia M Jiménez-Ceja
- Diabetes Division, University of Texas Health Science Center at San Antonio, 7703 Floyd Curl Drive, San Antonio, 78229, TX, USA
- Division of Health Sciences, Department of Medicine and Nutrition, University of Guanajuato, Guanajuato, Mexico
- Departamento de Investigación, Hospital Regional de Alta Especialidad del Bajío, Guanajuato, Mexico
| | - Andrea Hansis-Diarte
- Diabetes Division, University of Texas Health Science Center at San Antonio, 7703 Floyd Curl Drive, San Antonio, 78229, TX, USA
| | - Ralph A DeFronzo
- Diabetes Division, University of Texas Health Science Center at San Antonio, 7703 Floyd Curl Drive, San Antonio, 78229, TX, USA
- Audie L Murphy VA Hospital, South Texas Veteran Health Care System, San Antonio, TX, USA
| | - Franco Folli
- Diabetes Division, University of Texas Health Science Center at San Antonio, 7703 Floyd Curl Drive, San Antonio, 78229, TX, USA
| | - Devjit Tripathy
- Diabetes Division, University of Texas Health Science Center at San Antonio, 7703 Floyd Curl Drive, San Antonio, 78229, TX, USA.
- Audie L Murphy VA Hospital, South Texas Veteran Health Care System, San Antonio, TX, USA.
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100
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Pires RH, Saraiva MJ, Damas AM, Kellermayer MSZ. Force spectroscopy reveals the presence of structurally modified dimers in transthyretin amyloid annular oligomers. J Mol Recognit 2016; 30. [PMID: 27808434 DOI: 10.1002/jmr.2587] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2016] [Revised: 09/21/2016] [Accepted: 09/30/2016] [Indexed: 12/17/2022]
Abstract
Toxicity in amyloidogenic protein misfolding disorders is thought to involve intermediate states of aggregation associated with the formation of amyloid fibrils. Despite their relevance, the heterogeneity and transience of these oligomers have placed great barriers in our understanding of their structural properties. Among amyloid intermediates, annular oligomers or annular protofibrils have raised considerable interest because they may contribute to a mechanism of cellular toxicity via membrane permeation. Here we investigated, by using AFM force spectroscopy, the structural detail of amyloid annular oligomers from transthyretin (TTR), a protein involved in systemic and neurodegenerative amyloidogenic disorders. Manipulation was performed in situ, in the absence of molecular handles and using persistence length-fit values to select relevant curves. Force curves reveal the presence of dimers in TTR annular oligomers that unfold via a series of structural intermediates. This is in contrast with the manipulation of native TTR that was more often manipulated over length scales compatible with a TTR monomer and without unfolding intermediates. Imaging and force spectroscopy data suggest that dimers are formed by the assembly of monomers in a head-to-head orientation with a nonnative interface along their β-strands. Furthermore, these dimers stack through nonnative contacts that may enhance the stability of the misfolded structure.
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Affiliation(s)
- Ricardo H Pires
- Department of Biophysics and Radiation Biology, Semmelweis University, Budapest, Hungary.,Institute for Molecular and Cell Biology (IBMC), Porto, Portugal
| | - Maria J Saraiva
- Institute for Molecular and Cell Biology (IBMC), Porto, Portugal.,Instituto de Ciências Biomédicas de Abel Salazar (ICBAS), Universidade do Porto, Porto, Portugal
| | - Ana M Damas
- Institute for Molecular and Cell Biology (IBMC), Porto, Portugal.,Instituto de Ciências Biomédicas de Abel Salazar (ICBAS), Universidade do Porto, Porto, Portugal
| | - Miklós S Z Kellermayer
- Department of Biophysics and Radiation Biology, Semmelweis University, Budapest, Hungary.,MTA-SE Molecular Biophysics Research Group, Budapest, Hungary
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