1
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Su H, Masters CL, Bush AI, Barnham KJ, Reid GE, Vella LJ. Exploring the significance of lipids in Alzheimer's disease and the potential of extracellular vesicles. Proteomics 2024; 24:e2300063. [PMID: 37654087 DOI: 10.1002/pmic.202300063] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2023] [Revised: 08/07/2023] [Accepted: 08/14/2023] [Indexed: 09/02/2023]
Abstract
Lipids play a significant role in maintaining central nervous system (CNS) structure and function, and the dysregulation of lipid metabolism is known to occur in many neurological disorders, including Alzheimer's disease. Here we review what is currently known about lipid dyshomeostasis in Alzheimer's disease. We propose that small extracellular vesicle (sEV) lipids may provide insight into the pathophysiology and progression of Alzheimer's disease. This stems from the recognition that sEV likely contributes to disease pathogenesis, but also an understanding that sEV can serve as a source of potential biomarkers. While the protein and RNA content of sEV in the CNS diseases have been studied extensively, our understanding of the lipidome of sEV in the CNS is still in its infancy.
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Affiliation(s)
- Huaqi Su
- The Florey, The University of Melbourne, Parkville, Victoria, Australia
- School of Chemistry, Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Parkville, Victoria, Australia
| | - Colin L Masters
- The Florey, The University of Melbourne, Parkville, Victoria, Australia
| | - Ashley I Bush
- The Florey, The University of Melbourne, Parkville, Victoria, Australia
| | - Kevin J Barnham
- The Florey, The University of Melbourne, Parkville, Victoria, Australia
| | - Gavin E Reid
- School of Chemistry, Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Parkville, Victoria, Australia
- Department of Biochemistry and Pharmacology, The University of Melbourne, Parkville, Victoria, Australia
| | - Laura J Vella
- The Florey, The University of Melbourne, Parkville, Victoria, Australia
- Department of Surgery, The Royal Melbourne Hospital, The University of Melbourne, Parkville, Victoria, Australia
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2
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Kolmogorov VS, Erofeev AS, Barykin EP, Timoshenko RV, Lopatukhina EV, Kozin SA, Gorbacheva LR, Salikhov SV, Klyachko NL, Mitkevich VA, Edwards CRW, Korchev YE, Makarov AA, Gorelkin PV. Scanning Ion-Conductance Microscopy for Studying β-Amyloid Aggregate Formation on Living Cell Surfaces. Anal Chem 2023; 95:15943-15949. [PMID: 37856787 DOI: 10.1021/acs.analchem.3c02806] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2023]
Abstract
β-Amyloid aggregation on living cell surfaces is described as responsible for the neurotoxicity associated with different neurodegenerative diseases. It is suggested that the aggregation of β-amyloid (Aβ) peptide on neuronal cell surface leads to various deviations of its vital function due to myriad pathways defined by internalization of calcium ions, apoptosis promotion, reduction of membrane potential, synaptic activity loss, etc. These are associated with structural reorganizations and pathologies of the cell cytoskeleton mainly involving actin filaments and microtubules and consequently alterations of cell mechanical properties. The effect of amyloid oligomers on cells' Young's modulus has been observed in a variety of studies. However, the precise connection between the formation of amyloid aggregates on cell membranes and their effects on the local mechanical properties of living cells is still unresolved. In this work, we have used correlative scanning ion-conductance microscopy (SICM) to study cell topography, Young's modulus mapping, and confocal imaging of Aβ aggregate formation on living cell surfaces. However, it is well-known that the cytoskeleton state is highly connected to the intracellular level of reactive oxygen species (ROS). The effect of Aβ leads to the induction of oxidative stress, actin polymerization, and stress fiber formation. We measured the reactive oxygen species levels inside single cells using platinum nanoelectrodes to demonstrate the connection of ROS and Young's modulus of cells. SICM can be successfully applied to studying the cytotoxicity mechanisms of Aβ aggregates on living cell surfaces.
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Affiliation(s)
- Vasilii S Kolmogorov
- National University of Science and Technology "MISIS", 119049 Moscow, Russian Federation
- Lomonosov Moscow State University, 119991 Moscow, Russian Federation
| | - Alexander S Erofeev
- National University of Science and Technology "MISIS", 119049 Moscow, Russian Federation
| | - Evgeny P Barykin
- Engelhardt Institute of Molecular Biology of Russian Academy of Sciences, 119991 Moscow, Russian Federation
| | - Roman V Timoshenko
- National University of Science and Technology "MISIS", 119049 Moscow, Russian Federation
| | - Elena V Lopatukhina
- National University of Science and Technology "MISIS", 119049 Moscow, Russian Federation
| | - Sergey A Kozin
- Engelhardt Institute of Molecular Biology of Russian Academy of Sciences, 119991 Moscow, Russian Federation
| | - Lyubov R Gorbacheva
- Lomonosov Moscow State University, 119991 Moscow, Russian Federation
- Pirogov Russian National Research Medical University, 117997 Moscow, Russian Federation
| | - Sergey V Salikhov
- National University of Science and Technology "MISIS", 119049 Moscow, Russian Federation
| | | | - Vladimir A Mitkevich
- Engelhardt Institute of Molecular Biology of Russian Academy of Sciences, 119991 Moscow, Russian Federation
| | | | - Yuri E Korchev
- Nano Life Science Institute (WPI-NanoLSI), Kanazawa University, 920-1192 Kanazawa, Japan
- Department of Medicine, Imperial College London, SW7 2AZ London, United Kingdom
| | - Alexander A Makarov
- Engelhardt Institute of Molecular Biology of Russian Academy of Sciences, 119991 Moscow, Russian Federation
| | - Petr V Gorelkin
- National University of Science and Technology "MISIS", 119049 Moscow, Russian Federation
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3
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Viles JH. Imaging Amyloid-β Membrane Interactions: Ion-Channel Pores and Lipid-Bilayer Permeability in Alzheimer's Disease. ANGEWANDTE CHEMIE (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2023; 135:e202215785. [PMID: 38515735 PMCID: PMC10952214 DOI: 10.1002/ange.202215785] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Indexed: 03/08/2023]
Abstract
The accumulation of the amyloid-β peptides (Aβ) is central to the development of Alzheimer's disease. The mechanism by which Aβ triggers a cascade of events that leads to dementia is a topic of intense investigation. Aβ self-associates into a series of complex assemblies with different structural and biophysical properties. It is the interaction of these oligomeric, protofibril and fibrillar assemblies with lipid membranes, or with membrane receptors, that results in membrane permeability and loss of cellular homeostasis, a key event in Alzheimer's disease pathology. Aβ can have an array of impacts on lipid membranes, reports have included: a carpeting effect; a detergent effect; and Aβ ion-channel pore formation. Recent advances imaging these interactions are providing a clearer picture of Aβ induced membrane disruption. Understanding the relationship between different Aβ structures and membrane permeability will inform therapeutics targeting Aβ cytotoxicity.
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Affiliation(s)
- John H. Viles
- Department of Biochemistry, SBBS, Queen MaryUniversity of LondonUK
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4
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Viles JH. Imaging Amyloid-β Membrane Interactions: Ion-Channel Pores and Lipid-Bilayer Permeability in Alzheimer's Disease. Angew Chem Int Ed Engl 2023; 62:e202215785. [PMID: 36876912 PMCID: PMC10953358 DOI: 10.1002/anie.202215785] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Revised: 03/02/2023] [Accepted: 03/03/2023] [Indexed: 03/07/2023]
Abstract
The accumulation of the amyloid-β peptides (Aβ) is central to the development of Alzheimer's disease. The mechanism by which Aβ triggers a cascade of events that leads to dementia is a topic of intense investigation. Aβ self-associates into a series of complex assemblies with different structural and biophysical properties. It is the interaction of these oligomeric, protofibril and fibrillar assemblies with lipid membranes, or with membrane receptors, that results in membrane permeability and loss of cellular homeostasis, a key event in Alzheimer's disease pathology. Aβ can have an array of impacts on lipid membranes, reports have included: a carpeting effect; a detergent effect; and Aβ ion-channel pore formation. Recent advances imaging these interactions are providing a clearer picture of Aβ induced membrane disruption. Understanding the relationship between different Aβ structures and membrane permeability will inform therapeutics targeting Aβ cytotoxicity.
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Affiliation(s)
- John H. Viles
- Department of Biochemistry, SBBS, Queen MaryUniversity of LondonUK
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5
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Tiwari A, Pradhan S, Sannigrahi A, Mahakud AK, Jha S, Chattopadhyay K, Biswas M, Saleem M. “Interplay of lipid-head group and packing defects in driving Amyloid-beta mediated myelin-like model membrane deformation”. J Biol Chem 2023; 299:104653. [PMID: 36990217 PMCID: PMC10148160 DOI: 10.1016/j.jbc.2023.104653] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Revised: 02/24/2023] [Accepted: 03/21/2023] [Indexed: 03/29/2023] Open
Abstract
Accumulating evidence suggests that amyloid plaque associated myelin lipid loss as a result of elevated amyloid burden might also contribute to Alzheimer's disease. The amyloid fibrils though closely associated with lipids under physiological conditions, however, the progression of membrane remodeling events leading to lipid-fibril assembly remains unknown. Here we first reconstitute the interaction of Aβ-40 with myelin-like model membrane and show that the binding of Aβ-40 induces extensive tubulation. To look into the mechanism of membrane tubulation we chose a set of membrane conditions varying in lipid packing density and net charge that allows us to dissect the contribution of lipid specificity of Aβ-40 binding, aggregation kinetics, and subsequent changes in membrane parameters such as fluidity, diffusion, and compressibility modulus. We show that the binding of Aβ-40 depends predominantly on the lipid packing defect densities and electrostatic interactions and results in rigidification of the myelin-like model membrane during the early phase of amyloid aggregation. Furthermore, elongation of Aβ-40 into higher oligomeric and fibrillar species leads to eventual fluidization of the model membrane followed by extensive lipid membrane tubulation observed in the late phase. Taken together, our results capture mechanistic insights into snapshots of temporal dynamics of Aβ-40 - myelin-like model membrane interaction and demonstrate how short timescale, local phenomena of binding, and fibril-mediated load generation results in the consequent association of lipids with growing amyloid fibrils.
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6
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The interactions of amyloid β aggregates with phospholipid membranes and the implications for neurodegeneration. Biochem Soc Trans 2023; 51:147-159. [PMID: 36629697 DOI: 10.1042/bst20220434] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2022] [Revised: 12/20/2022] [Accepted: 12/22/2022] [Indexed: 01/12/2023]
Abstract
Misfolding, aggregation and accumulation of Amyloid-β peptides (Aβ) in neuronal tissue and extracellular matrix are hallmark features of Alzheimer's disease (AD) pathology. Soluble Aβ oligomers are involved in neuronal toxicity by interacting with the lipid membrane, compromising its integrity, and affecting the function of receptors. These facts indicate that the interaction between Aβ oligomers and cell membranes may be one of the central molecular level factors responsible for the onset of neurodegeneration. The present review provides a structural understanding of Aβ neurotoxicity via membrane interactions and contributes to understanding early events in Alzheimer's disease.
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7
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Abstract
Perturbation of cell membranes by amyloid β (Ab) peptide oligomers is one possible mechanism of cytotoxicity in Alzheimer's disease, but the structure of such Ab-membrane complexes is unknown. Here we examine the stability of several putative structures by implicit membrane and all-atom molecular dynamics simulations. The structures include (a) a variety of models proposed by other researchers in the past, (b) a heptameric β barrel determined by grafting the Ab sequence onto α-hemolysin, (c) a similar structure with modified strand orientation and turn location based on an experimental β-hairpin structure, (d) oligomers inserting C-terminal β hairpins into one leaflet of the bilayer, (e) oligomers forming parallel C-terminal β barrels, and (f) a helical hexamer made of C-terminal fragments. The α-hemolysin-grafted structure and its alternately oriented variant are stable in the membrane and form an aqueous pore. In contrast, the C-terminal parallel barrels are not stable, presumably due to excessive hydrophobicity of their inner surface. The helical hexamer also failed to stabilize an aqueous pore for the same reason. The C-terminal hairpin-inserting structures remain stably inserted but, again, do not form an aqueous pore. Our results suggest that only β-barrels inserting a combination of C-terminal and other residues can form stable aqueous pores.
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Affiliation(s)
- Aliasghar Sepehri
- Department of Chemistry, City College of New York, CUNY, 160 Convent Avenue, New York, New York10031, United States
| | - Themis Lazaridis
- Department of Chemistry, City College of New York, CUNY, 160 Convent Avenue, New York, New York10031, United States.,Graduate Programs in Chemistry, Biochemistry, and Physics, The Graduate Center, City University of New York, 365 Fifth Avenue, New York, New York10016, United States
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8
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Mahakud AK, Shaikh J, Rifa Iqbal VV, Gupta A, Tiwari A, Saleem M. Amyloids on Membrane Interfaces: Implications for Neurodegeneration. J Membr Biol 2022; 255:705-722. [PMID: 35670831 DOI: 10.1007/s00232-022-00245-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2022] [Accepted: 05/12/2022] [Indexed: 12/24/2022]
Abstract
Membrane interfaces are vital for various cellular processes, and their involvement in neurodegenerative disorders such as Alzheimer's and Parkinson's disease has taken precedence in recent years. The amyloidogenic proteins associated with neurodegenerative diseases interact with the neuronal membrane through various means, which has implications for both the onset and progression of the disease. The parameters that regulate the interaction between the membrane and the amyloids remain poorly understood. The review focuses on the various aspects of membrane interactions of amyloids, particularly amyloid-β (Aβ) peptides and Tau involved in Alzheimer's and α-synuclein involved in Parkinson's disease. The genetic, cell biological, biochemical, and biophysical studies that form the basis for our current understanding of the membrane interactions of Aβ peptides, Tau, and α-synuclein are discussed.
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Affiliation(s)
- Amaresh Kumar Mahakud
- School of Biological Sciences, National Institute of Science Education and Research, Bhubaneswar, India.,Homi Bhabha National Institute, Mumbai, India
| | - Jafarulla Shaikh
- School of Biological Sciences, National Institute of Science Education and Research, Bhubaneswar, India.,Homi Bhabha National Institute, Mumbai, India
| | - V V Rifa Iqbal
- School of Biological Sciences, National Institute of Science Education and Research, Bhubaneswar, India.,Homi Bhabha National Institute, Mumbai, India
| | - Abhinav Gupta
- School of Biological Sciences, National Institute of Science Education and Research, Bhubaneswar, India.,Homi Bhabha National Institute, Mumbai, India
| | - Anuj Tiwari
- Department of Life Sciences, National Institute of Technology, Rourkela, India
| | - Mohammed Saleem
- School of Biological Sciences, National Institute of Science Education and Research, Bhubaneswar, India. .,Homi Bhabha National Institute, Mumbai, India.
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9
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Saha J, Bose P, Dhakal S, Ghosh P, Rangachari V. Ganglioside-Enriched Phospholipid Vesicles Induce Cooperative Aβ Oligomerization and Membrane Disruption. Biochemistry 2022; 61:2206-2220. [PMID: 36173882 PMCID: PMC9840156 DOI: 10.1021/acs.biochem.2c00495] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
A major hallmark of Alzheimer's disease (AD) is the accumulation of extracellular aggregates of amyloid-β (Aβ). Structural polymorphism observed among Aβ fibrils in AD brains seem to correlate with the clinical subtypes suggesting a link between fibril polymorphism and pathology. Since fibrils emerge from a templated growth of low-molecular-weight oligomers, understanding the factors affecting oligomer generation is important. Membrane lipids are key factors to influence early stages of Aβ aggregation and oligomer generation, which cause membrane disruption. We have previously demonstrated that conformationally discrete Aβ oligomers can be generated by modulating the charge, composition, and chain length of lipids and surfactants. Here, we extend our studies into liposomal models by investigating Aβ oligomerization on large unilamellar vesicles (LUVs) of total brain extracts (TBE), reconstituted lipid rafts (LRs), or 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC). Varying the vesicle composition by specifically increasing the amount of GM1 gangliosides as a constituent, we found that only GM1-enriched liposomes induce the formation of toxic, low-molecular-weight oligomers. Furthermore, we found that the aggregation on liposome surface and membrane disruption are highly cooperative and sensitive to membrane surface characteristics. Numerical simulations confirm such a cooperativity and reveal that GM1-enriched liposomes form twice as many pores as those formed in the absence GM1. Overall, this study uncovers mechanisms of cooperativity between oligomerization and membrane disruption under controlled lipid compositional bias, and refocuses the significance of the early stages of Aβ aggregation in polymorphism, propagation, and toxicity in AD.
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Affiliation(s)
- Jhinuk Saha
- Department of Chemistry and Biochemistry, School of Mathematics and Natural Sciences, University of Southern Mississippi, Hattiesburg, Mississippi 39406, United States
| | - Priyankar Bose
- Department of Computer Science, Virginia Commonwealth University, Richmond, Virginia 23220, United States
| | - Shailendra Dhakal
- Center for Molecular and Cellular Biosciences, University of Southern Mississippi, Hattiesburg, Mississippi 39406, United States
| | - Preetam Ghosh
- Department of Computer Science, Virginia Commonwealth University, Richmond, Virginia 23220, United States
| | - Vijayaraghavan Rangachari
- Department of Chemistry and Biochemistry, School of Mathematics and Natural Sciences, University of Southern Mississippi, Hattiesburg, Mississippi 39406, United States; Center for Molecular and Cellular Biosciences, University of Southern Mississippi, Hattiesburg, Mississippi 39406, United States
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10
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Morris C, Kent TW, Shen F, Wojcikiewicz EP, Du D. Effects of the Hydrophilic N-Terminal Region on Aβ-Mediated Membrane Disruption. J Phys Chem B 2021; 125:7671-7678. [PMID: 34252282 DOI: 10.1021/acs.jpcb.1c03413] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Amyloidogenesis of amyloid-β (Aβ) peptides is intimately related to pathological neurodegeneration in Alzheimer's disease. Here, we investigated the membrane damage activity of Aβ40 and its derivatives that contain mutation at the N-terminal charged residues using a membrane leakage assay. A model 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) phospholipid vesicle encapsulating the fluorescent dye carboxyfluorescein was used in the study. Our results show that the mutations of the N-terminal charged residues of Aβ40 significantly affect the peptide-induced membrane leakage. The results suggest that favorable electrostatic interactions of the N-terminal charged residues and the phosphatidylcholine membrane surface are crucial in Aβ-mediated membrane permeation. The flexible and charge-rich N-terminal region may play a critical role in directing Aβ self-association on the membrane surface and in anchoring and stabilizing the peptide aggregates inserted in the phospholipid membrane, which are closely related with membrane disruption activity of Aβ. The results provide new mechanistic insight into the Aβ-mediated membrane damage process, which may be critical for understanding the mechanism of Aβ neurotoxicity in Alzheimer's disease.
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Affiliation(s)
- Clifford Morris
- Department of Chemistry and Biochemistry, Florida Atlantic University, Boca Raton, Florida 33431, United States
| | - Thomas W Kent
- Department of Chemistry and Biochemistry, Florida Atlantic University, Boca Raton, Florida 33431, United States
| | - Fengyun Shen
- Department of Chemistry and Biochemistry, Florida Atlantic University, Boca Raton, Florida 33431, United States
| | - Ewa P Wojcikiewicz
- Department of Biomedical Science, Charles E. Schmidt College of Medicine, Florida Atlantic University, Boca Raton, Florida 33431, United States
| | - Deguo Du
- Department of Chemistry and Biochemistry, Florida Atlantic University, Boca Raton, Florida 33431, United States
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11
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Deo T, Cheng Q, Paul S, Qiang W, Potapov A. Application of DNP-enhanced solid-state NMR to studies of amyloid-β peptide interaction with lipid membranes. Chem Phys Lipids 2021; 236:105071. [PMID: 33716023 DOI: 10.1016/j.chemphyslip.2021.105071] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Revised: 02/13/2021] [Accepted: 03/01/2021] [Indexed: 11/16/2022]
Abstract
The cellular membrane disruption induced by the aggregation of Aβ peptide has been proposed as a plausible cause of neuronal cell death during Alzheimer's disease. The molecular-level details of the Aβ interaction with cellular membranes were previously probed using solid state NMR (ssNMR), however, due to the limited sensitivity of the latter, studies were limited to samples with high Aβ-to-lipid ratio. The dynamic nuclear polarization (DNP) is a technique for increasing the sensitivity of NMR. In this work we demonstrate the feasibility of DNP-enhanced ssNMR studies of Aβ40 peptide interacting with various model liposomes: (1) a mixture of zwitterionic 1-palmitoyl-2-oleoyl-glycero-3-phosphocholine (POPC) and negatively charged 1-palmitoyl-2-oleoyl-sn-glycero-3-phospho-(1'-rac-glycerol) (POPG); (2) a mixture of POPC, POPG, cholesterol, sphingomyelin and ganglioside GM1; (3) the synaptic plasma membrane vesicles (SPMVs) extracted from rat brain tissues. In addition, DNP-ssNMR was applied to capturing changes in Aβ40 conformation taking place upon the peptide insertion into POPG liposomes. The signal enhancements under conditions of DNP allow carrying out informative 2D ssNMR experiments with about 0.25 mg of Aβ40 peptides (i.e. reaching Aβ40-to-lipid ratio of 1:200). In the studied liposome models, the 13C NMR chemical shifts at many 13C-labelled sites of Aβ40 are characteristic of β-sheets. In addition, in POPG liposomes the peptide forms hydrophobic contacts F19-L34 and F19-I32. Both the chemical shifts and hydrophobic contacts of Aβ40 in POPG remain the same before and after 8 h of incubation. This suggests that conformation at the 13C-labelled sites of the peptide is similar before and after the insertion process. Overall, our results demonstrate that DNP helps to overcome the sensitivity limitation of ssNMR, and thereby expand the applicability of ssNMR for charactering the Aβ peptide interacting with lipids.
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Affiliation(s)
- Thomas Deo
- School of Physics and Astronomy, University of Nottingham, University Park, Nottingham, NG7 2RD, UK
| | - Qinghui Cheng
- Department of Chemistry, Binghamton University, the State University of New York, Binghamton, NY, 13902, USA
| | - Subhadip Paul
- School of Physics and Astronomy, University of Nottingham, University Park, Nottingham, NG7 2RD, UK
| | - Wei Qiang
- Department of Chemistry, Binghamton University, the State University of New York, Binghamton, NY, 13902, USA
| | - Alexey Potapov
- School of Physics and Astronomy, University of Nottingham, University Park, Nottingham, NG7 2RD, UK.
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12
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Grigolato F, Arosio P. The role of surfaces on amyloid formation. Biophys Chem 2021; 270:106533. [PMID: 33529995 DOI: 10.1016/j.bpc.2020.106533] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Revised: 12/18/2020] [Accepted: 12/18/2020] [Indexed: 01/02/2023]
Abstract
Interfaces can strongly accelerate or inhibit protein aggregation, destabilizing proteins that are stable in solution or, conversely, stabilizing proteins that are aggregation-prone. Although this behaviour is well-known, our understanding of the molecular mechanisms underlying surface-induced protein aggregation is still largely incomplete. A major challenge is represented by the high number of physico-chemical parameters involved, which are highly specific to the considered combination of protein, surface properties, and solution conditions. The key aspect determining the role of interfaces is the relative propensity of the protein to aggregate at the surface with respect to bulk. In this review, we discuss the multiple molecular determinants that regulate this balance. We summarize current experimental techniques aimed at characterizing protein aggregation at interfaces, and highlight the need to complement experimental analysis with theoretical modelling. In particular, we illustrate how chemical kinetic analysis can be combined with experimental methods to provide insights into the molecular mechanisms underlying surface-induced protein aggregation, under both stagnant and agitation conditions. We summarize recent progress in the study of important amyloids systems, focusing on selected relevant interfaces.
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Affiliation(s)
- Fulvio Grigolato
- Department of Chemistry and Applied Biosciences, Institute for Chemical and Bioengineering, ETH Zurich, Zurich 8093, Switzerland
| | - Paolo Arosio
- Department of Chemistry and Applied Biosciences, Institute for Chemical and Bioengineering, ETH Zurich, Zurich 8093, Switzerland.
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13
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Dey S, Das A, Dey A, Maiti S. Membrane affinity of individual toxic protein oligomers determined at the single-molecule level. Phys Chem Chem Phys 2020; 22:14613-14620. [PMID: 32483579 DOI: 10.1039/d0cp00450b] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Oligomers are the key suspects in protein aggregation-linked diseases, such as Alzheimer's and Type II diabetes, and most likely exert their toxicity by interacting with lipid membranes. However, the "which oligomer" question remains an obstacle in understanding the disease mechanism, as the exact identity of the toxic oligomer(s) is not yet known. Oligomers exist as a mixture of species of different sizes (i.e. as different 'n-mers') in a physiological solution, making it difficult to determine the properties of individual species. Here we demonstrate a method based on single-molecule photo-bleaching (smPB) which can provide an answer to the "which oligomer" question, at least as far as membrane affinity is concerned. We calculate the ratio of the oligomer size distribution of human Islet Amyloid Polypeptide (IAPP) in the aqueous phase and that on a coexisting artificial lipid bilayer, and this measures the relative membrane affinity of individual oligomeric species. A problem with smPB measurements is that they can be very sensitive to pre-measurement bleaching. Here we correct for pre-bleaching using a covalently linked multimeric peptide as a bleaching standard. We find that the order of membrane affinity for IAPP n-mers is trimer > dimer > tetramer ≫ monomer. Our results agree well with the average membrane affinity values of oligomeric and monomeric solutions previously measured with Fluorescence Correlation Spectroscopy. The "which oligomer" question, in the context of membrane affinity, can therefore, be solved quantitatively for any membrane-active toxic protein aggregate.
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Affiliation(s)
- Simli Dey
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005, India.
| | - Anirban Das
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005, India.
| | - Arpan Dey
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005, India.
| | - Sudipta Maiti
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005, India.
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14
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Ghadami SA, Shevidi S, Hosseinzadeh L, Adibi H. Synthesis and in vitro quantification of amyloid fibrils by barbituric and thiobarbituric acid-based chromene derivatives. Biophys Chem 2020; 269:106522. [PMID: 33352334 DOI: 10.1016/j.bpc.2020.106522] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2020] [Revised: 12/04/2020] [Accepted: 12/06/2020] [Indexed: 01/09/2023]
Abstract
Neurodegenerative disease is caused by the abnormal build-up of proteins in and around cells called amyloid. The amyloid fibril formation and its mechanism have been investigated with various techniques, including dye-binding assay. Thioflavin T (ThT) has been one of the most widely used dyes for quantifying amyloid deposits, but ThT has a weak fluorescence signal especially at low concentration of amyloid fibrils, low lipophilicity and positive charge that makes it unable to cross the blood-brain barrier (BBB) to detect amyloid fibrils in vivo. Hence, there is a strong motivation for designing and developing the new compounds for in vitro amyloid quantification and in vivo amyloid imaging. The need for new probes to detect amyloid fibrils, especially within the cell, is highlighted by the fact that an accurate understanding of the molecular details of amyloid fibril formation is required to design and develop strategies for controlling the amyloid formation, and this needs more reliable probes for amyloid identification. In this work, we synthesized and applied barbituric and thiobarbituric acid-based chromene derivatives, as new fluorescent dyes to quantitatively detect the amyloid fibrils of bovine serum albumin (BSA) and human insulin in comparison with native soluble proteins or amorphous aggregation. Our results showed that among the 14 synthesized compounds, five compounds 4a, 4h, 4j, 4k, and 4l could selectively and specifically bind to amyloid fibrils while other compounds demonstrated a low-affinity binding. Furthermore, according to the cell viability experiment, compounds 4a, 4j and 4l at low concentration of compounds are not toxic, especially compound 4j which could be used as a suitable candidate for in vivo study. Further studies are needed to determine all the properties of compounds, especially in vivo experiments.
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Affiliation(s)
| | - Setayesh Shevidi
- Department of Biotechnology, Faculty of Biological Sciences, Alzahra University, Tehran, Iran
| | - Leila Hosseinzadeh
- Pharmaceutical Sciences Research Center, Health Institute, Kermanshah University of Medical Sciences, Kermanshah, Iran
| | - Hadi Adibi
- Pharmaceutical Sciences Research Center, Health Institute, Kermanshah University of Medical Sciences, Kermanshah, Iran.
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15
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Farrugia MY, Caruana M, Ghio S, Camilleri A, Farrugia C, Cauchi RJ, Cappelli S, Chiti F, Vassallo N. Toxic oligomers of the amyloidogenic HypF-N protein form pores in mitochondrial membranes. Sci Rep 2020; 10:17733. [PMID: 33082392 PMCID: PMC7575562 DOI: 10.1038/s41598-020-74841-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Accepted: 10/06/2020] [Indexed: 12/30/2022] Open
Abstract
Studies on the amyloidogenic N-terminal domain of the E. coli HypF protein (HypF-N) have contributed significantly to a detailed understanding of the pathogenic mechanisms in neurodegenerative diseases characterised by the formation of misfolded oligomers, by proteins such as amyloid-β, α-synuclein and tau. Given that both cell membranes and mitochondria are increasingly recognised as key targets of oligomer toxicity, we investigated the damaging effects of aggregates of HypF-N on mitochondrial membranes. Essentially, we found that HypF-N oligomers characterised by high surface hydrophobicity (type A) were able to trigger a robust permeabilisation of mito-mimetic liposomes possessing cardiolipin-rich membranes and dysfunction of isolated mitochondria, as demonstrated by a combination of mitochondrial shrinking, lowering of mitochondrial membrane potential and cytochrome c release. Furthermore, using single-channel electrophysiology recordings we obtained evidence that the type A aggregates induced currents reflecting formation of ion-conducting pores in mito-mimetic planar phospholipid bilayers, with multi-level conductances ranging in the hundreds of pS at negative membrane voltages. Conversely, HypF-N oligomers with low surface hydrophobicity (type B) could not permeabilise or porate mitochondrial membranes. These results suggest an inherent toxicity of membrane-active aggregates of amyloid-forming proteins to mitochondria, and that targeting of oligomer-mitochondrial membrane interactions might therefore afford protection against such damage.
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Affiliation(s)
- Maria Ylenia Farrugia
- Department of Physiology and Biochemistry, Faculty of Medicine and Surgery, University of Malta, Msida, Malta
- Centre for Molecular Medicine and Biobanking, University of Malta, Msida, Malta
| | - Mario Caruana
- Centre for Molecular Medicine and Biobanking, University of Malta, Msida, Malta
| | - Stephanie Ghio
- Department of Physiology and Biochemistry, Faculty of Medicine and Surgery, University of Malta, Msida, Malta
- Centre for Molecular Medicine and Biobanking, University of Malta, Msida, Malta
| | - Angelique Camilleri
- Department of Physiology and Biochemistry, Faculty of Medicine and Surgery, University of Malta, Msida, Malta
- Centre for Molecular Medicine and Biobanking, University of Malta, Msida, Malta
| | | | - Ruben J Cauchi
- Department of Physiology and Biochemistry, Faculty of Medicine and Surgery, University of Malta, Msida, Malta
- Centre for Molecular Medicine and Biobanking, University of Malta, Msida, Malta
| | - Sara Cappelli
- Section of Biochemistry, Department of Experimental and Clinical Biomedical Sciences, University of Florence, 50134, Florence, Italy
| | - Fabrizio Chiti
- Section of Biochemistry, Department of Experimental and Clinical Biomedical Sciences, University of Florence, 50134, Florence, Italy
| | - Neville Vassallo
- Department of Physiology and Biochemistry, Faculty of Medicine and Surgery, University of Malta, Msida, Malta.
- Centre for Molecular Medicine and Biobanking, University of Malta, Msida, Malta.
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16
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Matsuhisa K, Cai L, Saito A, Sakaue F, Kamikawa Y, Fujiwara S, Asada R, Kudo Y, Imaizumi K. Toxic effects of endoplasmic reticulum stress transducer BBF2H7-derived small peptide fragments on neuronal cells. Brain Res 2020; 1749:147139. [PMID: 33010207 DOI: 10.1016/j.brainres.2020.147139] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Revised: 09/10/2020] [Accepted: 09/26/2020] [Indexed: 11/24/2022]
Abstract
Aggregation, fibril formation, and deposition of amyloid β (Aβ) protein are believed to be the central pathogeneses of Alzheimer's disease (AD). Numerous studies have shown that fibril formation is promoted by preformed seeds at the beginning of the aggregation process. Therefore, aggregated molecules that promote fibrillization of Aβ protein as seeds could affect the pathology. We recently found that approximately 40 amino acid hydrophobic peptides, BBF2H7-derived small peptide (BSP) fragments, are generated via intramembranous cleavage under endoplasmic reticulum (ER) stress conditions. Interestingly, similar to Aβ protein, the fragments exhibit a high aggregation propensity and form fibril structures. It has been noted that ER stress is involved in the pathogenesis of AD. In this study, we examined the effect of BSP fragments on aggregation and cytotoxicity of Aβ1-40 protein, which is generated as a major species of Aβ protein, but has a lower aggregative property than Aβ1-42 protein. We demonstrated that BSP fragments promote aggregation of Aβ1-40 protein. Aggregates of Aβ1-40 protein mediated by BSP fragments also exhibited potent neurotoxicity. Our findings suggest the possibility that BSP fragments affect accumulation of Aβ proteins and are involved in the pathogenesis of AD.
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Affiliation(s)
- Koji Matsuhisa
- Department of Biochemistry, Institute of Biomedical & Health Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8553, Japan; Department of Stress Protein Processing, Institute of Biomedical & Health Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8553, Japan
| | - Longjie Cai
- Department of Biochemistry, Institute of Biomedical & Health Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8553, Japan
| | - Atsushi Saito
- Department of Biochemistry, Institute of Biomedical & Health Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8553, Japan; Department of Stress Protein Processing, Institute of Biomedical & Health Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8553, Japan
| | - Fumika Sakaue
- Department of Stress Protein Processing, Institute of Biomedical & Health Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8553, Japan
| | - Yasunao Kamikawa
- Department of Stress Protein Processing, Institute of Biomedical & Health Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8553, Japan
| | - Sachiko Fujiwara
- Department of Stress Protein Processing, Institute of Biomedical & Health Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8553, Japan
| | - Rie Asada
- Department of Medicine, Division of Endocrinology, Metabolism, and Lipid Research, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Yukitsuka Kudo
- Department of Gerontology and Geriatrics, Institute of Development, Aging and Cancer, Tohoku University, Sendai, Miyagi 980-8575, Japan
| | - Kazunori Imaizumi
- Department of Biochemistry, Institute of Biomedical & Health Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima 734-8553, Japan.
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17
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Sosa AFC, de Olivera da Silva SM, Morgan GP, Schwartz DK, Kaar JL. Mixed Phospholipid Vesicles Catalytically Inhibit and Reverse Amyloid Fibril Formation. J Phys Chem Lett 2020; 11:7417-7422. [PMID: 32803986 PMCID: PMC10164471 DOI: 10.1021/acs.jpclett.0c02074] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
While many approaches to reduce fibrillation of amyloid-β (Aβ) have been aimed at slowing fibril formation, the degradation of fibrils remains challenging. We provide insight into fibril degradation as well as the inhibition of fiber formation by lipid vesicles composed of 1,2-dioleoyl-sn-glycero-3-phosphocholine and 1,2-dioleoyl-sn-glycero-3-phospho-(1'-rac-glycerol). In the presence of vesicles with the optimal lipid composition, fibril formation was inhibited up to 76%. Additionally, by tuning the lipid composition, mature fibril content decreased up to 74% and the β-sheet content of Aβ was significantly reduced. The reduction in fibril and β-sheet content was consistent with a decrease in fibril diameter and could be attributed to the chaperone-like activity of the mixed vesicles. While demonstrating this remarkable activity, our findings present new evidence that lipid composition has a significant effect on the strength of the interaction between lipid bilayers and Aβ peptides/fibrils. This understanding has intriguing therapeutic implications in treating protein misfolding diseases.
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Affiliation(s)
- Andres F. Chaparro Sosa
- Department of Chemical and Biological Engineering, University of Colorado, Boulder, CO 80309
| | | | - Garry P. Morgan
- Department of Molecular, Cellular and Developmental Biology, University of Colorado, Boulder, CO, 80309
| | - Daniel K. Schwartz
- Department of Chemical and Biological Engineering, University of Colorado, Boulder, CO 80309
- Corresponding Authors: Daniel K. Schwartz, University of Colorado Boulder, Department of Chemical and Biological Engineering, Campus Box 596, Boulder, CO 80309, Tel: (303) 735-0240, Fax: (303) 492-4341, ; Joel L. Kaar, University of Colorado Boulder, Department of Chemical and Biological Engineering, Campus Box 596, Boulder, CO 80309, Tel: (303) 492-6031, Fax: (303) 492-4341,
| | - Joel L. Kaar
- Department of Chemical and Biological Engineering, University of Colorado, Boulder, CO 80309
- Corresponding Authors: Daniel K. Schwartz, University of Colorado Boulder, Department of Chemical and Biological Engineering, Campus Box 596, Boulder, CO 80309, Tel: (303) 735-0240, Fax: (303) 492-4341, ; Joel L. Kaar, University of Colorado Boulder, Department of Chemical and Biological Engineering, Campus Box 596, Boulder, CO 80309, Tel: (303) 492-6031, Fax: (303) 492-4341,
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18
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Highlighting the effect of amyloid beta assemblies on the mechanical properties and conformational stability of cell membrane. J Mol Graph Model 2020; 100:107670. [PMID: 32711259 DOI: 10.1016/j.jmgm.2020.107670] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2020] [Revised: 06/09/2020] [Accepted: 06/10/2020] [Indexed: 01/05/2023]
Abstract
Alzheimer disease (AD) is the most common cause of dementia, characterized by a progressive decline in cognitive function due to the abnormal aggregation and deposition of Amyloid beta (Aβ) fibrils in the brain of patients. In this context, the molecular mechanisms of protein misfolding and aggregation that are known to induce significant biophysical alterations in cells, including destabilization of plasma membranes, remain partially unclear. Physical interaction between the Aβ assemblies and the membrane leads to the disruption of the cell membrane in multiple ways including, surface carpeting, generation of transmembrane channels and detergent-like membrane dissolution. Understanding the impact of amyloidogenic protein in different stages of aggregation with the plasma membrane, plays a crucial role to fully elucidate the pathological mechanisms of AD. Within this framework, computer simulations represent a powerful tool able to shed lights on the interactions governing the structural influence of Aβ proteins on biological membrane. In this study, molecular dynamics (MD) simulations have been performed in order to characterize how POPC bilayer conformational and mechanical properties are affected by the interaction with Aβ11-42 peptide, oligomer and fibril.
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19
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Azouz M, Cullin C, Lecomte S, Lafleur M. Membrane domain modulation of Aβ 1-42 oligomer interactions with supported lipid bilayers: an atomic force microscopy investigation. NANOSCALE 2019; 11:20857-20867. [PMID: 31657431 DOI: 10.1039/c9nr06361g] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Alzheimer's disease is a devastating pathology affecting an increasing number of individuals following the general rise in life expectancy. Amyloid peptide Aβ1-42 has been identified as one of the main culprits of the disease. The peptide has been shown to have major effects on lipid membranes, including membrane fragmentation. The membrane composition has been identified as a factor that plays a pivotal role in regulating peptide/membrane interactions and several results suggest that lipid domains, or rafts, can promote peptide-induced membrane damage. In this work, we examined the effects of lipid segregation on the membrane-perturbing ability of Aβ1-42 and an oligomeric mutant (G37C), a peptide that shares common features with the suspected toxic intermediates involved in the neurodegeneration process. Atomic force microscopy (AFM) was used to determine the impact of these peptides on the supported lipid bilayers of various compositions. In 1,2-dioleoyl-sn-glycero-3-phosphocholine/1,2-dipalmitoyl-sn-glycero-3-phosphocholine/cholesterol (DOPC/DPPC/cholesterol) and DOPC/sphingomyelin/cholesterol ternary mixtures, two systems exhibiting liquid-liquid phase separations, it was shown that Aβ1-42 and G37C exclusively aggregated on liquid-disordered-phase domains, creating large deposits and even causing membrane fragmentation for the latter composition. Cholesterol and ganglioside GM1, the two most documented lipids in the context of Alzheimer's disease, are also considered to play a crucial role in promoting detrimental interactions with amyloid peptides. We show that, in model 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) membranes, the presence of either cholesterol or GM1 in a proportion of 10 mol%, a content supposed to lead to domain formation, favoured the association of both Aβ1-42 and G37C, leading to a harmful membrane fragmentation. The AFM results established that the presence of domains favoured membrane perturbations induced by the amyloid peptides. It is proposed that lipid packing defects at the domain interface could act as adsorption and nucleation sites for the amyloid peptides. The more extensive bilayer perturbations induced by G37C compared to Aβ1-42 supported this hypothesis, indicating that oligomers that cannot mature to the fibril state can present considerable toxicity.
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Affiliation(s)
- Mehdi Azouz
- Chimie et Biologie des Membranes et Nanoobjets, CBMN CNRS UMR 5248, Université de Bordeaux, Allée Geoffroy de Saint-Hilaire, 33600 Pessac, France and Department of Chemistry, Université de Montréal, Montréal, Québec, Canada.
| | - Christophe Cullin
- Chimie et Biologie des Membranes et Nanoobjets, CBMN CNRS UMR 5248, Université de Bordeaux, Allée Geoffroy de Saint-Hilaire, 33600 Pessac, France
| | - Sophie Lecomte
- Chimie et Biologie des Membranes et Nanoobjets, CBMN CNRS UMR 5248, Université de Bordeaux, Allée Geoffroy de Saint-Hilaire, 33600 Pessac, France
| | - Michel Lafleur
- Department of Chemistry, Université de Montréal, Montréal, Québec, Canada.
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20
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Ntarakas N, Ermilova I, Lyubartsev AP. Effect of lipid saturation on amyloid-beta peptide partitioning and aggregation in neuronal membranes: molecular dynamics simulations. EUROPEAN BIOPHYSICS JOURNAL: EBJ 2019; 48:813-824. [PMID: 31655893 PMCID: PMC6853862 DOI: 10.1007/s00249-019-01407-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/27/2019] [Revised: 10/02/2019] [Accepted: 10/13/2019] [Indexed: 12/05/2022]
Abstract
Aggregation of amyloid-\documentclass[12pt]{minimal}
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\begin{document}$$\beta $$\end{document}β (Aβ) peptides, cleaved from the amyloid precursor protein, is known as a precursor of the Alzheimer’s disease (AD). It is also known that Alzheimer’s disease is characterized by a substantial decrease of the amount of polyunsaturated lipids in the neuronal membranes of the frontal gray matter. To get insight into possible interconnection of these phenomena, we have carried out molecular dynamics simulations of two fragments of A\documentclass[12pt]{minimal}
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\begin{document}$$\beta $$\end{document}β peptide, A\documentclass[12pt]{minimal}
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\begin{document}$$_{1-28}$$\end{document}1-28 and A\documentclass[12pt]{minimal}
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\begin{document}$$_{26-40}$$\end{document}26-40, in four different lipid bilayers: two monocomponent ones (14:0-14:0 PC, 18:0-22:6 PC), and two bilayers containing mixtures of 18:0-18:0 PE, 22:6-22:6 PE, 16:0-16:0 PC and 18:1-18:1 PC lipids of composition mimicking neuronal membranes in a “healthy” and “AD” brain. The simulations showed that the presence of lipids with highly unsaturated 22:6cis fatty acids chains strongly affects the interaction of amyloid-\documentclass[12pt]{minimal}
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\begin{document}$$\beta $$\end{document}β peptides with lipid membranes. The polyunsaturated lipids cause stronger adsorption of A\documentclass[12pt]{minimal}
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\begin{document}$$\beta $$\end{document}β-peptides by the membrane and lead to weaker binding between peptides when the latter form aggregates. This difference in the behaviour observed in monocomponent bilayers is propagated in a similar fashion to the mixed membranes mimicking composition of neuronal membranes in “healthy” and “AD” brains, with “healthy” membrane having higher fraction of polyunsaturated lipids. Our simulations give strong indication that it can be physical–chemical background of the interconnection between amyloid fibrillization causing Alzheimer’s disease, and content of polyunsaturated lipids in the neuronal membranes.
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Affiliation(s)
- Nikolaos Ntarakas
- Department of Materials and Environmental Chemistry, Stockholm's University, 10691, Stockholm, Sweden
| | - Inna Ermilova
- Department of Materials and Environmental Chemistry, Stockholm's University, 10691, Stockholm, Sweden
| | - Alexander P Lyubartsev
- Department of Materials and Environmental Chemistry, Stockholm's University, 10691, Stockholm, Sweden.
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21
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Beasley M, Stonebraker AR, Hasan I, Kapp KL, Liang BJ, Agarwal G, Groover S, Sedighi F, Legleiter J. Lipid Membranes Influence the Ability of Small Molecules To Inhibit Huntingtin Fibrillization. Biochemistry 2019; 58:4361-4373. [PMID: 31608620 DOI: 10.1021/acs.biochem.9b00739] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Several diseases, including Alzheimer's disease, Parkinson's disease, and Huntington's disease (HD), are associated with specific proteins aggregating and depositing within tissues and/or cellular compartments. The aggregation of these proteins is characterized by the formation of extended, β-sheet rich fibrils, termed amyloid. In addition, a variety of other aggregate species also form, including oligomers and protofibrils. Specifically, HD is caused by the aggregation of the huntingtin (htt) protein that contains an expanded polyglutamine domain. Due to the link between protein aggregation and disease, small molecule aggregation inhibitors have been pursued as potential therapeutic agents. Two such small molecules are epigallocatechin 3-gallate (EGCG) and curcumin, both of which inhibit the fibril formation of several amyloid-forming proteins. However, amyloid formation is a complex process that is strongly influenced by the protein's environment, leading to distinct aggregation pathways. Thus, changes in the protein's environment may alter the effectiveness of aggregation inhibitors. A well-known modulator of amyloid formation is lipid membranes. Here, we investigated if the presence of lipid vesicles altered the ability of EGCG or curcumin to modulate htt aggregation and influence the interaction of htt with lipid membranes. The presence of 1-palmitoyl-2-oleoyl-glycero-3-phosphocholine or total brain lipid extract vesicles prevented the curcumin from inhibiting htt fibril formation. In contrast, EGCG's inhibition of htt fibril formation persisted in the presence of lipids. Collectively, these results highlight the complexity of htt aggregation and demonstrate that the presence of lipid membranes is a key modifier of the ability of small molecules to inhibit htt fibril formation.
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Affiliation(s)
- Maryssa Beasley
- The C. Eugene Bennett Department of Chemistry , West Virginia University , 217 Clark Hall , Morgantown , West Virginia 26506 , United States
| | - Alyssa R Stonebraker
- The C. Eugene Bennett Department of Chemistry , West Virginia University , 217 Clark Hall , Morgantown , West Virginia 26506 , United States
| | - Iraj Hasan
- The C. Eugene Bennett Department of Chemistry , West Virginia University , 217 Clark Hall , Morgantown , West Virginia 26506 , United States
| | - Kathryn L Kapp
- The C. Eugene Bennett Department of Chemistry , West Virginia University , 217 Clark Hall , Morgantown , West Virginia 26506 , United States
| | - Barry J Liang
- The C. Eugene Bennett Department of Chemistry , West Virginia University , 217 Clark Hall , Morgantown , West Virginia 26506 , United States
| | - Garima Agarwal
- The C. Eugene Bennett Department of Chemistry , West Virginia University , 217 Clark Hall , Morgantown , West Virginia 26506 , United States
| | - Sharon Groover
- The C. Eugene Bennett Department of Chemistry , West Virginia University , 217 Clark Hall , Morgantown , West Virginia 26506 , United States
| | - Faezeh Sedighi
- The C. Eugene Bennett Department of Chemistry , West Virginia University , 217 Clark Hall , Morgantown , West Virginia 26506 , United States
| | - Justin Legleiter
- The C. Eugene Bennett Department of Chemistry , West Virginia University , 217 Clark Hall , Morgantown , West Virginia 26506 , United States.,Rockefeller Neurosciences Institute , West Virginia University , 1 Medical Center Drive , P.O. Box 9303, Morgantown , West Virginia 26505 , United States.,Department of Neuroscience , West Virginia University , 1 Medical Center Drive , P.O. Box 9303, Morgantown , West Virginia 26505 , United States
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22
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Lv Z, Hashemi M, Banerjee S, Zagorski K, Rochet JC, Lyubchenko YL. Assembly of α-synuclein aggregates on phospholipid bilayers. BIOCHIMICA ET BIOPHYSICA ACTA. PROTEINS AND PROTEOMICS 2019; 1867:802-812. [PMID: 31226488 PMCID: PMC6661114 DOI: 10.1016/j.bbapap.2019.06.006] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Revised: 05/29/2019] [Accepted: 06/14/2019] [Indexed: 01/17/2023]
Abstract
The spontaneous self-assembly of α-synuclein (α-syn) into aggregates of different morphologies is associated with the development of Parkinson's disease. However, the mechanism behind the spontaneous assembly remains elusive. The current study shows a novel effect of phospholipid bilayers on the assembly of the α-syn aggregates. Using time-lapse atomic force microscopy, it was discovered that α-syn assembles into aggregates on bilayer surfaces, even at the nanomolar concentration range. The efficiency of the aggregation process depends on the membrane composition, with the greatest efficiency observed for of 1-palmitoyl-2-oleoyl-sn-glycero-3-phospho-l-serine (POPS). Importantly, assembled aggregates can dissociate from the surface, suggesting that on-surface aggregation is a mechanism by which pathological aggregates may be produced. Computational modeling revealed that dimers of α-syn assembled rapidly, through the membrane-bound monomer on POPS bilayer, due to an aggregation-prone orientation of α-syn. Interaction of α-syn with 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) leads to a binding mode that does not induce a fast assembly of the dimer. Based on these findings, we propose a model in which the interaction of α-syn with membranes plays a critical role initiating the formation of α-syn aggregates and the overall aggregation process.
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Affiliation(s)
- Zhengjian Lv
- Department of Pharmaceutical Sciences, University of Nebraska Medical Center, 986025 Nebraska Medical Center, Omaha, NE 68198-6025, United States of America; Bruker Nano Surfaces Division, 112 Robin Hill Road, Goleta, Santa Barbara, CA 93117, United States of America
| | - Mohtadin Hashemi
- Department of Pharmaceutical Sciences, University of Nebraska Medical Center, 986025 Nebraska Medical Center, Omaha, NE 68198-6025, United States of America
| | - Siddhartha Banerjee
- Department of Pharmaceutical Sciences, University of Nebraska Medical Center, 986025 Nebraska Medical Center, Omaha, NE 68198-6025, United States of America
| | - Karen Zagorski
- Department of Pharmaceutical Sciences, University of Nebraska Medical Center, 986025 Nebraska Medical Center, Omaha, NE 68198-6025, United States of America
| | - Jean-Christophe Rochet
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN, United States of America; Purdue Institute for Integrative Neuroscience, Purdue University, West Lafayette, IN, United States of America
| | - Yuri L Lyubchenko
- Department of Pharmaceutical Sciences, University of Nebraska Medical Center, 986025 Nebraska Medical Center, Omaha, NE 68198-6025, United States of America.
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23
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Maity BK, Das AK, Dey S, Moorthi UK, Kaur A, Dey A, Surendran D, Pandit R, Kallianpur M, Chandra B, Chandrakesan M, Arumugam S, Maiti S. Ordered and Disordered Segments of Amyloid-β Drive Sequential Steps of the Toxic Pathway. ACS Chem Neurosci 2019; 10:2498-2509. [PMID: 30763064 DOI: 10.1021/acschemneuro.9b00015] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
While the roles of intrinsically disordered protein domains in driving interprotein interactions are increasingly well-appreciated, the mechanism of toxicity of disease-causing disordered proteins remains poorly understood. A prime example is Alzheimer's disease (AD) associated amyloid beta (Aβ). Aβ oligomers are highly toxic partially structured peptide assemblies with a distinct ordered region (residues ∼10-40) and a shorter disordered region (residues ∼1-9). Here, we investigate the role of this disordered domain and its relation to the ordered domain in the manifestation of toxicity through a set of Aβ fragments and stereoisomers designed for this purpose. We measure their effects on lipid membranes and cultured neurons, probing their toxicity, intracellular distributions, and specific molecular interactions using the techniques of confocal imaging, lattice light sheet imaging, fluorescence lifetime imaging, and fluorescence correlation spectroscopy. Remarkably, we find that neither part-Aβ10-40 or Aβ1-9, is toxic by itself. The ordered part (Aβ10-40) is the major determinant of how Aβ attaches to lipid bilayers, enters neuronal cells, and localizes primarily in the late endosomal compartments. However, once Aβ enters the cell, it is the disordered part (only when it is connected to the rest of the peptide) that has a strong and stereospecific interaction with an unknown cellular component, as demonstrated by distinct changes in the fluorescence lifetime of a fluorophore attached to the N-terminal. This interaction appears to commit Aβ to the toxic pathway. Our findings correlate well with Aβ sites of familial AD mutations, a significant fraction of which cluster in the disordered region. We conclude that, while the ordered region dictates attachment and cellular entry, the key to toxicity lies in the ordered part presenting the disordered part for a specific cellular interaction.
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Affiliation(s)
- Barun Kumar Maity
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005, India
| | - Anand Kant Das
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005, India
| | - Simli Dey
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005, India
| | | | | | - Arpan Dey
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005, India
| | - Dayana Surendran
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005, India
| | - Rucha Pandit
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005, India
| | - Mamata Kallianpur
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005, India
| | - Bappaditya Chandra
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005, India
| | - Muralidharan Chandrakesan
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005, India
| | | | - Sudipta Maiti
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005, India
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24
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De novo aggregation of Alzheimer's Aβ25-35 peptides in a lipid bilayer. Sci Rep 2019; 9:7161. [PMID: 31073226 PMCID: PMC6509337 DOI: 10.1038/s41598-019-43685-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Accepted: 04/27/2019] [Indexed: 11/28/2022] Open
Abstract
A potential mechanism of cytotoxicity attributed to Alzheimer’s Aβ peptides postulates that their aggregation disrupts membrane structure causing uncontrollable permeation of Ca2+ ions. To gain molecular insights into these processes, we have performed all-atom explicit solvent replica exchange with solute tempering molecular dynamics simulations probing aggregation of the naturally occurring Aβ fragment Aβ25-35 within the DMPC lipid bilayer. To compare the impact produced on the bilayer by Aβ25-35 oligomers and monomers, we used as a control our previous simulations, which explored binding of Aβ25-35 monomers to the same bilayer. We found that compared to monomeric species aggregation results in much deeper insertion of Aβ25-35 peptides into the bilayer hydrophobic core causing more pronounced disruption in its structure. Aβ25-35 peptides aggregate by incorporating monomer-like structures with stable C-terminal helix. As a result the Aβ25-35 dimer features unusual helix head-to-tail topology supported by a parallel off-registry interface. Such topology affords further growth of an aggregate by recruiting additional peptides. Free energy landscape reveals that inserted dimers represent the dominant equilibrium state augmented by two metastable states associated with surface bound dimers and inserted monomers. Using the free energy landscape we propose the pathway of Aβ25-35 binding, aggregation, and insertion into the lipid bilayer.
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25
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Lockhart C, Smith AK, Klimov DK. Methionine Oxidation Changes the Mechanism of Aβ Peptide Binding to the DMPC Bilayer. Sci Rep 2019; 9:5947. [PMID: 30976055 PMCID: PMC6459879 DOI: 10.1038/s41598-019-42304-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2019] [Accepted: 03/28/2019] [Indexed: 12/22/2022] Open
Abstract
Using all-atom explicit solvent replica exchange molecular dynamics simulations with solute tempering, we study the effect of methionine oxidation on Aβ10–40 peptide binding to the zwitterionic DMPC bilayer. By comparing oxidized and reduced peptides, we identified changes in the binding mechanism caused by this modification. First, Met35 oxidation unravels C-terminal helix in the bound peptides. Second, oxidation destabilizes intrapeptide interactions and expands bound peptides. We explain these outcomes by the loss of amphiphilic character of the C-terminal helix due to oxidation. Third, oxidation “polarizes” Aβ binding to the DMPC bilayer by strengthening the interactions of the C-terminus with lipids while largely releasing the rest of the peptide from bilayer. Fourth, in contrast to the wild-type peptide, oxidized Aβ induces significantly smaller bilayer thinning and drop in lipid density within the binding footprint. These observations are the consequence of mixing oxidized peptide amino acids with lipids promoted by enhanced Aβ conformational fluctuations. Fifth, methionine oxidation reduces the affinity of Aβ binding to the DMPC bilayer by disrupting favorable intrapeptide interactions upon binding, which offset the gains from better hydration. Reduced binding affinity of the oxidized Aβ may represent the molecular basis for its reduced cytotoxicity.
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Affiliation(s)
| | - Amy K Smith
- School of Systems Biology, George Mason University, Manassas, VA, 20110, USA
| | - Dmitri K Klimov
- School of Systems Biology, George Mason University, Manassas, VA, 20110, USA.
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26
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Bode DC, Freeley M, Nield J, Palma M, Viles JH. Amyloid-β oligomers have a profound detergent-like effect on lipid membrane bilayers, imaged by atomic force and electron microscopy. J Biol Chem 2019; 294:7566-7572. [PMID: 30948512 DOI: 10.1074/jbc.ac118.007195] [Citation(s) in RCA: 94] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Revised: 03/27/2019] [Indexed: 12/19/2022] Open
Abstract
The ability of amyloid-β peptide (Aβ) to disrupt membrane integrity and cellular homeostasis is believed to be central to Alzheimer's disease pathology. Aβ is reported to have various impacts on the lipid bilayer, but a clearer picture of Aβ influence on membranes is required. Here, we use atomic force and transmission electron microscopies to image the impact of different isolated Aβ assembly types on lipid bilayers. We show that only oligomeric Aβ can profoundly disrupt the bilayer, visualized as widespread lipid extraction and subsequent deposition, which can be likened to an effect expected from the action of a detergent. We further show that Aβ oligomers cause widespread curvature and discontinuities within lipid vesicle membranes. In contrast, this detergent-like effect was not observed for Aβ monomers and fibers, although Aβ fibers did laterally associate and embed into the upper leaflet of the bilayer. The marked impact of Aβ oligomers on membrane integrity identified here reveals a mechanism by which these oligomers may be cytotoxic.
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Affiliation(s)
- David C Bode
- From the School of Biological and Chemical Sciences, Queen Mary, University of London, Mile End Road, London E1 4NS, United Kingdom
| | - Mark Freeley
- From the School of Biological and Chemical Sciences, Queen Mary, University of London, Mile End Road, London E1 4NS, United Kingdom
| | - Jon Nield
- From the School of Biological and Chemical Sciences, Queen Mary, University of London, Mile End Road, London E1 4NS, United Kingdom
| | - Matteo Palma
- From the School of Biological and Chemical Sciences, Queen Mary, University of London, Mile End Road, London E1 4NS, United Kingdom
| | - John H Viles
- From the School of Biological and Chemical Sciences, Queen Mary, University of London, Mile End Road, London E1 4NS, United Kingdom
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27
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W. Pilkington IV A, Legleiter J. Challenges in understanding the structure/activity relationship of Aβ oligomers. AIMS BIOPHYSICS 2019. [DOI: 10.3934/biophy.2019.1.1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
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28
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Rangachari V, Dean DN, Rana P, Vaidya A, Ghosh P. Cause and consequence of Aβ - Lipid interactions in Alzheimer disease pathogenesis. BIOCHIMICA ET BIOPHYSICA ACTA. BIOMEMBRANES 2018; 1860:1652-1662. [PMID: 29526709 PMCID: PMC6133763 DOI: 10.1016/j.bbamem.2018.03.004] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/25/2017] [Revised: 02/28/2018] [Accepted: 03/02/2018] [Indexed: 12/14/2022]
Abstract
Self-templating propagation of protein aggregate conformations is increasingly becoming a significant factor in many neurological diseases. In Alzheimer disease (AD), intrinsically disordered amyloid-β (Aβ) peptides undergo aggregation that is sensitive to environmental conditions. High-molecular weight aggregates of Aβ that form insoluble fibrils are deposited as senile plaques in AD brains. However, low-molecular weight aggregates called soluble oligomers are known to be the primary toxic agents responsible for neuronal dysfunction. The aggregation process is highly stochastic involving both homotypic (Aβ-Aβ) and heterotypic (Aβ with interacting partners) interactions. Two of the important members of interacting partners are membrane lipids and surfactants, to which Aβ shows a perpetual association. Aβ-membrane interactions have been widely investigated for more than two decades, and this research has provided a wealth of information. Although this has greatly enriched our understanding, the objective of this review is to consolidate the information from the literature that collectively showcases the unique phenomenon of lipid-mediated Aβ oligomer generation, which has largely remained inconspicuous. This is especially important because Aβ aggregate "strains" are increasingly becoming relevant in light of the correlations between the structure of aggregates and AD phenotypes. Here, we will focus on aspects of Aβ-lipid interactions specifically from the context of how lipid modulation generates a wide variety of biophysically and biochemically distinct oligomer sub-types. This, we believe, will refocus our thinking on the influence of lipids and open new approaches in delineating the mechanisms of AD pathogenesis. 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)
- Vijayaraghavan Rangachari
- Department of Chemistry & Biochemistry, University of Southern Mississippi, Hattiesburg, MS 39406, USA.
| | - Dexter N Dean
- Department of Chemistry & Biochemistry, University of Southern Mississippi, Hattiesburg, MS 39406, USA
| | - Pratip Rana
- Department of Computer Science, Virginia Commonwealth University, Richmond, VA 23284, USA
| | - Ashwin Vaidya
- Department of Mathematical Science, Montclair State University, Montclair, NJ 07043, USA
| | - Preetam Ghosh
- Department of Computer Science, Virginia Commonwealth University, Richmond, VA 23284, USA
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29
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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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30
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Sun M, Zhao Y, Han M, Zhang B, Zhang X, Zhang Q, Lim NKH, Wang WA, Huang FD. TTC7 and Hyccin Regulate Neuronal Aβ42 Accumulation and its Associated Neural Deficits in Aβ42-Expressing Drosophila. J Alzheimers Dis 2018; 65:1001-1010. [PMID: 30103315 DOI: 10.3233/jad-170907] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Neuronal amyloid-β (Aβ) accumulation plays an important role in the pathogenesis of Alzheimer's disease (AD). The conformation and toxicity of Aβ are regulated by lipids on the plasma membrane. Previously, we found downregulation of Rolling Blackout (RBO) or phosphatidylinositol-4-kinase type IIIα (PI4KIIIα) reduces neuronal Aβ accumulation and associated neural deficits in a Drosophila model expressing Aβ42. In mammals, the homologs of RBO and PI4KIIIα were reported to form a plasma membrane-localized complex with a scaffold protein TTC7 and cytosolic protein Hyccin/FAM126A to tightly control the plasmalemmal level of phosphatidylinositol-4-phosphate. Here, we show genetic downregulation of Drosophila TTC7 and Hyccin also reduces neuronal Aβ accumulation and associated synaptic and motor defects as well as premature death in Aβ42-expressing flies, while overexpression of TTC7 and Hyccin produced the opposite effect. These results, together with our previous study, demonstrate that RBO/TTC7/PI4KIIIα/Hyccin regulate neuronal Aβ accumulation and associated neural deficits in the Drosophila model, further supporting the RBO/Efr3-PI4KIIIα complex as a potential therapeutic target for AD.
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Affiliation(s)
- Minghao Sun
- Shanghai Advanced Research Institute, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Yinghui Zhao
- Shanghai Advanced Research Institute, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, China.,Laboratory of Molecular Neurobiology, School of Life Sciences, Shanghai University, Shanghai, China
| | - Men Han
- Department of Neurology, Qingdao Municipal Hospital, School of Medicine, Qingdao University, Qingdao, China
| | - Baozhu Zhang
- Shanghai Advanced Research Institute, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Xiao Zhang
- Shanghai Advanced Research Institute, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Qichao Zhang
- Shanghai Advanced Research Institute, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, China.,Sino-Danish College, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing, China
| | - Nastasia K-H Lim
- Shanghai Advanced Research Institute, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, China.,Shanghai Institute of Materia Medica, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Wen-An Wang
- Department of Neurology, Xinhua Hospital Chongming Branch Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Fu-De Huang
- Shanghai Advanced Research Institute, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, China.,Sino-Danish College, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing, China
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31
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Meker S, Chin H, Sut TN, Cho NJ. Amyloid-β Peptide Triggers Membrane Remodeling in Supported Lipid Bilayers Depending on Their Hydrophobic Thickness. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2018; 34:9548-9560. [PMID: 30021071 DOI: 10.1021/acs.langmuir.8b01196] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Amyloid-β (Aβ) peptide has been implicated in Alzheimer's disease, which is a leading cause of death worldwide. The interaction of Aβ peptides with the lipid bilayers of neuronal cells is a critical step in disease pathogenesis. Recent evidence indicates that lipid bilayer thickness influences Aβ membrane-associated aggregation, while understanding how Aβ interacts with lipid bilayers remains elusive. To address this question, we employed supported lipid bilayer (SLB) platforms composed of different-length phosphatidylcholine (PC) lipids (C12:0 DLPC, C18:1 DOPC, C18:1-C16:0 POPC), and characterized the resulting interactions with soluble Aβ monomers. Quartz crystal microbalance-dissipation (QCM-D) experiments identified concentration-dependent Aβ peptide adsorption onto all tested SLBs, which was corroborated by fluorescence recovery after photobleaching (FRAP) experiments indicating that higher Aβ concentrations led to decreased membrane fluidity. These commonalities pointed to strong Aβ peptide-membrane interactions in all cases. Notably, time-lapsed fluorescence microscopy revealed major differences in Aβ-induced membrane morphological responses depending on SLB hydrophobic thickness. For thicker DOPC and POPC SLBs, membrane remodeling involved the formation of elongated tubule and globular structures as a passive means to regulate membrane stress depending on Aβ concentration. In marked contrast, thin DLPC SLBs were not able to accommodate extensive membrane remodeling. Taken together, our findings reveal that membrane thickness influences the membrane morphological response triggered upon Aβ adsorption.
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Affiliation(s)
- Sigalit Meker
- School of Materials Science and Engineering , Nanyang Technological University , 639798 , Singapore
- Centre for Biomimetic Sensor Science , Nanyang Technological University , 637553 , Singapore
| | - Hokyun Chin
- School of Materials Science and Engineering , Nanyang Technological University , 639798 , Singapore
- Centre for Biomimetic Sensor Science , Nanyang Technological University , 637553 , Singapore
| | - Tun Naw Sut
- School of Materials Science and Engineering , Nanyang Technological University , 639798 , Singapore
- Centre for Biomimetic Sensor Science , Nanyang Technological University , 637553 , Singapore
| | - Nam-Joon Cho
- School of Materials Science and Engineering , Nanyang Technological University , 639798 , Singapore
- Centre for Biomimetic Sensor Science , Nanyang Technological University , 637553 , Singapore
- School of Chemical and Biomedical Engineering , Nanyang Technological University , 637459 , Singapore
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32
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Smith AK, Klimov DK. Binding of Cytotoxic Aβ25–35 Peptide to the Dimyristoylphosphatidylcholine Lipid Bilayer. J Chem Inf Model 2018; 58:1053-1065. [DOI: 10.1021/acs.jcim.8b00045] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Amy K. Smith
- School of Systems Biology, George Mason University, Manassas, Virginia 20110, United States
| | - Dmitri K. Klimov
- School of Systems Biology, George Mason University, Manassas, Virginia 20110, United States
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33
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Cheng Q, Hu ZW, Doherty KE, Tobin-Miyaji YJ, Qiang W. The on-fibrillation-pathway membrane content leakage and off-fibrillation-pathway lipid mixing induced by 40-residue β-amyloid peptides in biologically relevant model liposomes. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2018; 1860:1670-1680. [PMID: 29548698 DOI: 10.1016/j.bbamem.2018.03.008] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2017] [Revised: 03/08/2018] [Accepted: 03/10/2018] [Indexed: 02/06/2023]
Abstract
Disruption of the synaptic plasma membrane (SPM) induced by the aggregation of β-amyloid (Aβ) peptides has been considered as a potential mechanism for the neurotoxicity of Aβ in Alzheimer's disease (AD). However, the molecular basis of such membrane disruption process remains unclear, mainly because of the severe systematic heterogeneity problem that prevents the high-resolution studies. Our previous studies using a two-component phosphatidylcholine (PC)/phosphatidylglycerol (PG) model liposome showed the presence of Aβ-induced membrane disruptions that were either on the pathway or off the pathway of fibril formation. The present study focuses on a more biologically relevant model membrane with compositions that mimic the outer leaflet of SPMs. The main findings are: (1) the two competing membrane disruption effects discovered in PC/PG liposomes and their general peptide-to-lipid-molar-ratio dependence persist in the more complicated membrane models; (2) the SPM-mimic membrane promotes the formation of certain "on-fibrillation-pathway" intermediates with higher α-helical structural population, which lead to more rapid and significant of membrane content leakage; (3) although the "on-fibrillation-pathway" intermediate structures show dependence on membrane compositions, there seems to be a common final fibril structure grown from different liposomes, suggesting that there may be a predominant fibril structure for 40-residue Aβ (i.e. Aβ40) peptides in biologically-relevant membranes. 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)
- Qinghui Cheng
- Department of Chemistry, State University of New York at Binghamton, Binghamton, NY 13902, United States
| | - Zhi-Wen Hu
- Department of Chemistry, State University of New York at Binghamton, Binghamton, NY 13902, United States
| | - Katelynne E Doherty
- Department of Chemistry, State University of New York at Binghamton, Binghamton, NY 13902, United States
| | - Yuto J Tobin-Miyaji
- Department of Chemistry, State University of New York at Binghamton, Binghamton, NY 13902, United States
| | - Wei Qiang
- Department of Chemistry, State University of New York at Binghamton, Binghamton, NY 13902, United States.
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34
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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: 95] [Impact Index Per Article: 15.8] [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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35
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Chaibva M, Gao X, Jain P, Campbell WA, Frey SL, Legleiter J. Sphingomyelin and GM1 Influence Huntingtin Binding to, Disruption of, and Aggregation on Lipid Membranes. ACS OMEGA 2018; 3:273-285. [PMID: 29399649 PMCID: PMC5793032 DOI: 10.1021/acsomega.7b01472] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2017] [Accepted: 12/25/2017] [Indexed: 05/09/2023]
Abstract
Huntington disease (HD) is an inherited neurodegenerative disease caused by the expansion beyond a critical threshold of a polyglutamine (polyQ) tract near the N-terminus of the huntingtin (htt) protein. Expanded polyQ promotes the formation of a variety of oligomeric and fibrillar aggregates of htt that accumulate into the hallmark proteinaceous inclusion bodies associated with HD. htt is also highly associated with numerous cellular and subcellular membranes that contain a variety of lipids. As lipid homeostasis and metabolism abnormalities are observed in HD patients, we investigated how varying both the sphingomyelin (SM) and ganglioside (GM1) contents modifies the interactions between htt and lipid membranes. SM composition is altered in HD, and GM1 has been shown to have protective effects in animal models of HD. A combination of Langmuir trough monolayer techniques, vesicle permeability and binding assays, and in situ atomic force microscopy (AFM) were used to directly monitor the interaction of a model, synthetic htt peptide and a full-length htt-exon1 recombinant protein with model membranes comprised of total brain lipid extract (TBLE) and varying amounts of exogenously added SM or GM1. The addition of either SM or GM1 decreased htt insertion into the lipid monolayers. However, TBLE vesicles with an increased SM content were more susceptible to htt-induced permeabilization, whereas GM1 had no effect on permeablization. Pure TBLE bilayers and TBLE bilayers enriched with GM1 developed regions of roughened, granular morphologies upon exposure to htt-exon1, but plateau-like domains with a smoother appearance formed in bilayers enriched with SM. Oligomeric aggregates were observed on all bilayer systems regardless of induced morphology. Collectively, these observations suggest that the lipid composition and its subsequent effects on membrane material properties strongly influence htt binding and aggregation on lipid membranes.
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Affiliation(s)
- Maxmore Chaibva
- The
C. Eugene Bennett Department of Chemistry, West Virginia University, 217 Clark Hall, P.O. Box 6045, Morgantown, West Virginia 26505, United States
| | - Xiang Gao
- The
C. Eugene Bennett Department of Chemistry, West Virginia University, 217 Clark Hall, P.O. Box 6045, Morgantown, West Virginia 26505, United States
| | - Pranav Jain
- The
C. Eugene Bennett Department of Chemistry, West Virginia University, 217 Clark Hall, P.O. Box 6045, Morgantown, West Virginia 26505, United States
| | - Warren A. Campbell
- Department
of Chemistry, Gettysburg College, 300 N. Washington Avenue, Campus Box 0393, Gettysburg, Pennsylvania 17325, United States
| | - Shelli L. Frey
- Department
of Chemistry, Gettysburg College, 300 N. Washington Avenue, Campus Box 0393, Gettysburg, Pennsylvania 17325, United States
- E-mail: . Phone: 717-337-6259 (S.L.F.)
| | - Justin Legleiter
- The
C. Eugene Bennett Department of Chemistry, West Virginia University, 217 Clark Hall, P.O. Box 6045, Morgantown, West Virginia 26505, United States
- Blanchette
Rockefeller Neurosciences Institutes, West
Virginia University, 1 Medical Center Dr., P.O. Box 9303, Morgantown, West Virginia 26505, United States
- E-mail: . Phone: 304-293-0175 (J.L.)
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36
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Oropesa-Nuñez R, Seghezza S, Dante S, Diaspro A, Cascella R, Cecchi C, Stefani M, Chiti F, Canale C. Interaction of toxic and non-toxic HypF-N oligomers with lipid bilayers investigated at high resolution with atomic force microscopy. Oncotarget 2018; 7:44991-45004. [PMID: 27391440 PMCID: PMC5216700 DOI: 10.18632/oncotarget.10449] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2016] [Accepted: 06/26/2016] [Indexed: 11/25/2022] Open
Abstract
Protein misfolded oligomers are considered the most toxic species amongst those formed in the process of amyloid formation and the molecular basis of their toxicity, although not completely understood, is thought to originate from the interaction with the cellular membrane. Here, we sought to highlight the molecular determinants of oligomer-membrane interaction by atomic force microscopy. We monitored the interaction between multiphase supported lipid bilayers and two types of HypF-N oligomers displaying different structural features and cytotoxicities. By our approach we imaged with unprecedented resolution the ordered and disordered lipid phases of the bilayer and different oligomer structures interacting with either phase. We identified the oligomers and lipids responsible for toxicity and, more generally, we established the importance of the membrane lipid component in mediating oligomer toxicity. Our findings support the importance of GM1 ganglioside in mediating the oligomer-bilayer interaction and support a mechanism of oligomer cytotoxicity involving bilayer destabilization by globular oligomers within GM1-rich ordered raft regions rather than by annular oligomers in the surrounding disordered membrane domains.
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Affiliation(s)
- Reinier Oropesa-Nuñez
- Department of Nanophysics, Istituto Italiano di Tecnologia, Genova, Italy.,DIBRIS Department, University of Genova, Genova, Italy
| | - Silvia Seghezza
- Department of Nanophysics, Istituto Italiano di Tecnologia, Genova, Italy
| | - Silvia Dante
- Department of Nanophysics, Istituto Italiano di Tecnologia, Genova, Italy
| | - Alberto Diaspro
- Department of Nanophysics, Istituto Italiano di Tecnologia, Genova, Italy.,Department of Physics, University of Genova, Genova, Italy
| | - Roberta Cascella
- Section of Biochemistry, Department of Biomedical Experimental and Clinical Sciences, University of Florence, Firenze, Italy
| | - Cristina Cecchi
- Section of Biochemistry, Department of Biomedical Experimental and Clinical Sciences, University of Florence, Firenze, Italy
| | - Massimo Stefani
- Section of Biochemistry, Department of Biomedical Experimental and Clinical Sciences, University of Florence, Firenze, Italy
| | - Fabrizio Chiti
- Section of Biochemistry, Department of Biomedical Experimental and Clinical Sciences, University of Florence, Firenze, Italy
| | - Claudio Canale
- Department of Nanophysics, Istituto Italiano di Tecnologia, Genova, Italy
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37
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Bryksa BC, Yada RY. Protein Structure Insights into the Bilayer Interactions of the Saposin-Like Domain of Solanum tuberosum Aspartic Protease. Sci Rep 2017; 7:16911. [PMID: 29208977 PMCID: PMC5717070 DOI: 10.1038/s41598-017-16734-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2017] [Accepted: 11/16/2017] [Indexed: 12/26/2022] Open
Abstract
Many plant aspartic proteases contain a saposin-like domain whose principal functions are intracellular sorting and host defence. Its structure is characterised by helical segments cross-linked by three highly conserved cystines. The present study on the saposin-like domain of Solanum tuberosum aspartic protease revealed that acidification from inactive to active conditions causes dimerisation and a strand-to-helix secondary structure transition independent of bilayer interaction. Bilayer fusion was shown to occur under reducing conditions yielding a faster shift to larger vesicle sizes relative to native conditions, implying that a lower level structural motif might be bilayer-active. Characterisation of peptide sequences based on the domain’s secondary structural regions showed helix-3 to be active (~4% of the full domain’s activity), and mutation of its sole positively charged residue resulted in loss of activity and disordering of structure. Also, the peptides’ respective circular dichroism spectra suggested that native folding within the full domain is dependent on surrounding structure. Overall, the present study reveals that the aspartic protease saposin-like domain active structure is an open saposin fold dimer whose formation is pH-dependent, and that a bilayer-active motif shared among non-saposin membrane-active proteins including certain plant defence proteins is nested within an overall structure essential for native functionality.
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Affiliation(s)
- Brian C Bryksa
- Ontario Agricultural College, University of Guelph, N1G 2W1, Guelph, Ontario, Canada
| | - Rickey Y Yada
- Faculty of Land and Food Systems, University of British Columbia, Vancouver, V6T 1Z4, British Columbia, Canada.
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38
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Lockhart C, Klimov DK. Cholesterol Changes the Mechanisms of Aβ Peptide Binding to the DMPC Bilayer. J Chem Inf Model 2017; 57:2554-2565. [PMID: 28910085 DOI: 10.1021/acs.jcim.7b00431] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Using isobaric-isothermal all-atom replica-exchange molecular dynamics (REMD) simulations, we investigated the equilibrium binding of Aβ10-40 monomers to the zwitterionic dimyristoylphosphatidylcholine (DMPC) bilayer containing cholesterol. Our previous REMD simulations, which studied binding of the same peptide to the cholesterol-free DMPC bilayer, served as a control, against which we measured the impact of cholesterol. Our findings are as follows. First, addition of cholesterol to the DMPC bilayer partially expels the Aβ peptide from the hydrophobic core and promotes its binding to bilayer polar headgroups. Using thermodynamic and energetics analyses, we argued that Aβ partial expulsion is not related to cholesterol-induced changes in lateral pressure within the bilayer but is caused by binding energetics, which favors Aβ binding to the surface of the densely packed cholesterol-rich bilayer. Second, cholesterol has a protective effect on the DMPC bilayer structure against perturbations caused by Aβ binding. More specifically, cholesterol reduces bilayer thinning and overall depletion of bilayer density beneath the Aβ binding footprint. Third, we found that the Aβ peptide contains a single cholesterol binding site, which involves hydrophobic C-terminal amino acids (Ile31-Val36), Phe19, and Phe20 from the central hydrophobic cluster, and cationic Lys28 from the turn region. This binding site accounts for about 76% of all Aβ-cholesterol interactions. Because cholesterol binding site in the Aβ10-40 peptide does not contain the GXXXG motif featured in cholesterol interactions with the transmembrane domain C99 of the β-amyloid precursor protein, we argued that the binding mechanisms for Aβ and C99 are distinct reflecting their different conformations and positions in the lipid bilayer. Fourth, cholesterol sharply reduces the helical propensity in the bound Aβ peptide. As a result, cholesterol largely eliminates the emergence of helical structure observed upon Aβ transition from a water environment to the cholesterol-free DMPC bilayer. We explain this effect by the formation of hydrogen bonds between cholesterol and the Aβ backbone, which prevent helix formation. Taken together, we expect that our simulations will advance understanding of a molecular-level mechanism behind the role of cholesterol in Alzheimer's disease.
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Affiliation(s)
- Christopher Lockhart
- School of Systems Biology, George Mason University , Manassas, Virginia 20110, United States
| | - Dmitri K Klimov
- School of Systems Biology, George Mason University , Manassas, Virginia 20110, United States
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Canale C, Oropesa-Nuñez R, Diaspro A, Dante S. Amyloid and membrane complexity: The toxic interplay revealed by AFM. Semin Cell Dev Biol 2017; 73:82-94. [PMID: 28860102 DOI: 10.1016/j.semcdb.2017.08.046] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2017] [Revised: 08/21/2017] [Accepted: 08/25/2017] [Indexed: 01/05/2023]
Abstract
Lipid membranes play a fundamental role in the pathological development of protein misfolding diseases. Several pieces of evidence suggest that the lipid membrane could act as a catalytic surface for protein aggregation. Furthermore, a leading theory indicates the interaction between the cell membrane and misfolded oligomer species as the responsible for cytotoxicity, hence, for neurodegeneration in disorders such as Alzheimer's and Parkinson's disease. The definition of the mechanisms that drive the interaction between pathological protein aggregates and plasma membrane is fundamental for the development of effective therapies for a large class of diseases. Atomic force microscopy (AFM) has been employed to study how amyloid aggregates affect the cell physiological properties. Considerable efforts were spent to characterize the interaction with model systems, i.e., planar supported lipid bilayers, but some works also addressed the problem directly on living cells. Here, an overview of the main works involving the use of the AFM on both model system and living cells will be provided. Different kind of approaches will be presented, as well as the main results derived from the AFM analysis.
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Affiliation(s)
- Claudio Canale
- Department of Nanophysics. Istituto Italiano di Tecnologia. Via Morego 30, 16163 Genova, Italy; Department of Physics, University of Genova, via Dodecaneso 33, 16146 Genova, Italy.
| | - Reinier Oropesa-Nuñez
- Department of Nanophysics. Istituto Italiano di Tecnologia. Via Morego 30, 16163 Genova, Italy; DIBRIS Department, University of Genova, viale Causa 13, 16145, Genova, Italy
| | - Alberto Diaspro
- Department of Nanophysics. Istituto Italiano di Tecnologia. Via Morego 30, 16163 Genova, Italy; Department of Physics, University of Genova, via Dodecaneso 33, 16146 Genova, Italy
| | - Silvia Dante
- Department of Nanophysics. Istituto Italiano di Tecnologia. Via Morego 30, 16163 Genova, Italy
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40
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Chemerovski‐Glikman M, Frenkel‐Pinter M, Mdah R, Abu‐Mokh A, Gazit E, Segal D. Inhibition of the Aggregation and Toxicity of the Minimal Amyloidogenic Fragment of Tau by Its Pro‐Substituted Analogues. Chemistry 2017; 23:9618-9624. [DOI: 10.1002/chem.201701218] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2017] [Indexed: 12/15/2022]
Affiliation(s)
- Marina Chemerovski‐Glikman
- Department of Molecular Microbiology & BiotechnologySagol Interdisciplinary School of NeurosciencesGeorge S. Wise Faculty of Life SciencesTel-Aviv University Tel-Aviv 69978 Israel
| | - Moran Frenkel‐Pinter
- Department of Molecular Microbiology & BiotechnologySagol Interdisciplinary School of NeurosciencesGeorge S. Wise Faculty of Life SciencesTel-Aviv University Tel-Aviv 69978 Israel
| | - Ragad Mdah
- Department of Molecular Microbiology & BiotechnologySagol Interdisciplinary School of NeurosciencesGeorge S. Wise Faculty of Life SciencesTel-Aviv University Tel-Aviv 69978 Israel
| | - Amjaad Abu‐Mokh
- Department of Molecular Microbiology & BiotechnologySagol Interdisciplinary School of NeurosciencesGeorge S. Wise Faculty of Life SciencesTel-Aviv University Tel-Aviv 69978 Israel
| | - Ehud Gazit
- Department of Molecular Microbiology & BiotechnologySagol Interdisciplinary School of NeurosciencesGeorge S. Wise Faculty of Life SciencesTel-Aviv University Tel-Aviv 69978 Israel
- Department of Materials Science and EngineeringIby and Aladar Fleischman Faculty of EngineeringTel Aviv University Tel Aviv 6997801 Israel
| | - Daniel Segal
- Department of Molecular Microbiology & BiotechnologySagol Interdisciplinary School of NeurosciencesGeorge S. Wise Faculty of Life SciencesTel-Aviv University Tel-Aviv 69978 Israel
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41
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Chaibva M, Jawahery S, Pilkington AW, Arndt JR, Sarver O, Valentine S, Matysiak S, Legleiter J. Acetylation within the First 17 Residues of Huntingtin Exon 1 Alters Aggregation and Lipid Binding. Biophys J 2017; 111:349-362. [PMID: 27463137 DOI: 10.1016/j.bpj.2016.06.018] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2015] [Revised: 06/06/2016] [Accepted: 06/15/2016] [Indexed: 02/06/2023] Open
Abstract
Huntington's disease (HD) is a genetic neurodegenerative disorder caused by an expanded polyglutamine (polyQ) domain near the N-terminus of the huntingtin (htt) protein. Expanded polyQ leads to htt aggregation. The first 17 amino acids (Nt(17)) in htt comprise a lipid-binding domain that undergoes a number of posttranslational modifications that can modulate htt toxicity and subcellular localization. As there are three lysines within Nt(17), we evaluated the impact of lysine acetylation on htt aggregation in solution and on model lipid bilayers. Acetylation of htt-exon1(51Q) and synthetic truncated htt-exon 1 mimicking peptides (Nt(17)-Q35-P10-KK) was achieved using a selective covalent label, sulfo-N-hydroxysuccinimide (NHSA). With this treatment, all three lysine residues (K6, K9, and K15) in Nt(17) were significantly acetylated. N-terminal htt acetylation retarded fibril formation in solution and promoted the formation of larger globular aggregates. Acetylated htt also bound lipid membranes and disrupted the lipid bilayer morphology less aggressively compared with the wild-type. Computational studies provided mechanistic insights into how acetylation alters the interaction of Nt(17) with lipid membranes. Our results highlight that N-terminal acetylation influences the aggregation of htt and its interaction with lipid bilayers.
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Affiliation(s)
- Maxmore Chaibva
- The C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, West Virginia
| | - Sudi Jawahery
- Fischell Department of Bioengineering, University of Maryland, College Park, Maryland
| | - Albert W Pilkington
- The C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, West Virginia
| | - James R Arndt
- The C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, West Virginia
| | - Olivia Sarver
- The C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, West Virginia
| | - Stephen Valentine
- The C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, West Virginia
| | - Silvina Matysiak
- Fischell Department of Bioengineering, University of Maryland, College Park, Maryland; Biophysics Program, Institute for Physical Chemistry and Technology, University of Maryland, College Park, Maryland.
| | - Justin Legleiter
- The C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, West Virginia; NanoSAFE, West Virginia University, Morgantown, West Virginia; Center for Neurosciences, West Virginia University, Morgantown, West Virginia.
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42
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Adegbuyiro A, Sedighi F, Pilkington AW, Groover S, Legleiter J. Proteins Containing Expanded Polyglutamine Tracts and Neurodegenerative Disease. Biochemistry 2017; 56:1199-1217. [PMID: 28170216 DOI: 10.1021/acs.biochem.6b00936] [Citation(s) in RCA: 90] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Several hereditary neurological and neuromuscular diseases are caused by an abnormal expansion of trinucleotide repeats. To date, there have been 10 of these trinucleotide repeat disorders associated with an expansion of the codon CAG encoding glutamine (Q). For these polyglutamine (polyQ) diseases, there is a critical threshold length of the CAG repeat required for disease, and further expansion beyond this threshold is correlated with age of onset and symptom severity. PolyQ expansion in the translated proteins promotes their self-assembly into a variety of oligomeric and fibrillar aggregate species that accumulate into the hallmark proteinaceous inclusion bodies associated with each disease. Here, we review aggregation mechanisms of proteins with expanded polyQ-tracts, structural consequences of expanded polyQ ranging from monomers to fibrillar aggregates, the impact of protein context and post-translational modifications on aggregation, and a potential role for lipid membranes in aggregation. As the pathogenic mechanisms that underlie these disorders are often classified as either a gain of toxic function or loss of normal protein function, some toxic mechanisms associated with mutant polyQ tracts will also be discussed.
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Affiliation(s)
- Adewale Adegbuyiro
- The C. Eugene Bennett Department of Chemistry, 217 Clark Hall, West Virginia University , Morgantown, West Virginia 26506, United States
| | - Faezeh Sedighi
- The C. Eugene Bennett Department of Chemistry, 217 Clark Hall, West Virginia University , Morgantown, West Virginia 26506, United States
| | - Albert W Pilkington
- The C. Eugene Bennett Department of Chemistry, 217 Clark Hall, West Virginia University , Morgantown, West Virginia 26506, United States
| | - Sharon Groover
- The C. Eugene Bennett Department of Chemistry, 217 Clark Hall, West Virginia University , Morgantown, West Virginia 26506, United States
| | - Justin Legleiter
- The C. Eugene Bennett Department of Chemistry, 217 Clark Hall, West Virginia University , Morgantown, West Virginia 26506, United States.,Blanchette Rockefeller Neurosciences Institute, Robert C. Byrd Health Sciences Center, P.O. Box 9304, West Virginia University , Morgantown, West Virginia 26506, United States.,NanoSAFE, P.O. Box 6223, West Virginia University , Morgantown, West Virginia 26506, United States
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43
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El Gaamouch F, Jing P, Xia J, Cai D. Alzheimer's Disease Risk Genes and Lipid Regulators. J Alzheimers Dis 2017; 53:15-29. [PMID: 27128373 DOI: 10.3233/jad-160169] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Brain lipid homeostasis plays an important role in Alzheimer's disease (AD) and other neurodegenerative disorders. Aggregation of amyloid-β peptide is one of the major events in AD. The complex interplay between lipids and amyloid-β accumulation has been intensively investigated. The proportions of lipid components including phospholipids, sphingolipids, and cholesterol are roughly similar across different brain regions under physiological conditions. However, disruption of brain lipid homeostasis has been described in AD and implicated in disease pathogenesis. Moreover, studies suggest that analysis of lipid composition in plasma and cerebrospinal fluid could improve our understanding of the disease development and progression, which could potentially serve as disease biomarkers and prognostic indicators for AD therapies. Here, we summarize the functional roles of AD risk genes and lipid regulators that modulate brain lipid homeostasis including different lipid species, lipid complexes, and lipid transporters, particularly their effects on amyloid processing, clearance, and aggregation, as well as neuro-toxicities that contribute to AD pathogenesis.
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Affiliation(s)
- Farida El Gaamouch
- James J Peters VA Medical Center, Research & Development, Bronx, NY, USA.,Department of Neurology, Alzheimer Disease Research Center, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Ping Jing
- The Central Hospital of Wuhan, China
| | | | - Dongming Cai
- James J Peters VA Medical Center, Research & Development, Bronx, NY, USA.,Department of Neurology, Alzheimer Disease Research Center, Icahn School of Medicine at Mount Sinai, New York, NY, USA.,The Central Hospital of Wuhan, China
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44
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Korshavn KJ, Satriano C, Lin Y, Zhang R, Dulchavsky M, Bhunia A, Ivanova MI, Lee YH, La Rosa C, Lim MH, Ramamoorthy A. Reduced Lipid Bilayer Thickness Regulates the Aggregation and Cytotoxicity of Amyloid-β. J Biol Chem 2017; 292:4638-4650. [PMID: 28154182 DOI: 10.1074/jbc.m116.764092] [Citation(s) in RCA: 131] [Impact Index Per Article: 18.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2016] [Revised: 01/31/2017] [Indexed: 11/06/2022] Open
Abstract
The aggregation of amyloid-β (Aβ) on lipid bilayers has been implicated as a mechanism by which Aβ exerts its toxicity in Alzheimer's disease (AD). Lipid bilayer thinning has been observed during both oxidative stress and protein aggregation in AD, but whether these pathological modifications of the bilayer correlate with Aβ misfolding is unclear. Here, we studied peptide-lipid interactions in synthetic bilayers of the short-chain lipid dilauroyl phosphatidylcholine (DLPC) as a simplified model for diseased bilayers to determine their impact on Aβ aggregate, protofibril, and fibril formation. Aβ aggregation and fibril formation in membranes composed of dioleoyl phosphatidylcholine (DOPC) or 1- palmitoyl-2-oleoyl phosphatidylcholine mimicking normal bilayers served as controls. Differences in aggregate formation and stability were monitored by a combination of thioflavin-T fluorescence, circular dichroism, atomic force microscopy, transmission electron microscopy, and NMR. Despite the ability of all three lipid bilayers to catalyze aggregation, DLPC accelerates aggregation at much lower concentrations and prevents the fibrillation of Aβ at low micromolar concentrations. DLPC stabilized globular, membrane-associated oligomers, which could disrupt the bilayer integrity. DLPC bilayers also remodeled preformed amyloid fibrils into a pseudo-unfolded, molten globule state, which resembled on-pathway, protofibrillar aggregates. Whereas the stabilized, membrane-associated oligomers were found to be nontoxic, the remodeled species displayed toxicity similar to that of conventionally prepared aggregates. These results provide mechanistic insights into the roles that pathologically thin bilayers may play in Aβ aggregation on neuronal bilayers, and pathological lipid oxidation may contribute to Aβ misfolding.
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Affiliation(s)
- Kyle J Korshavn
- From the Department of Chemistry.,Program in Biophysics, and
| | - Cristina Satriano
- the Department of Chemical Sciences, University of Catania, Catania 95124, Italy
| | - Yuxi Lin
- the Institute for Protein Research, Osaka University, Osaka 565-0871, Japan
| | | | - Mark Dulchavsky
- Department of Neurology, University of Michigan, Ann Arbor, Michigan 48109
| | - Anirban Bhunia
- the Department of Biophysics, Bose Institute, Kolkata 700009, India, and
| | - Magdalena I Ivanova
- Program in Biophysics, and.,Department of Neurology, University of Michigan, Ann Arbor, Michigan 48109
| | - Young-Ho Lee
- the Institute for Protein Research, Osaka University, Osaka 565-0871, Japan
| | - Carmelo La Rosa
- the Department of Chemical Sciences, University of Catania, Catania 95124, Italy
| | - Mi Hee Lim
- the Department of Chemistry, Ulsan National Institute of Science and Technology (UNIST), Ulsan 44919, Korea
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45
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Fojan P, Gurevich L. Atomic Force Microscopy Study of the Interactions of Indolicidin with Model Membranes and DNA. Methods Mol Biol 2017; 1548:201-215. [PMID: 28013506 DOI: 10.1007/978-1-4939-6737-7_14] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The cell membrane is the first barrier and quite often the primary target that antimicrobial peptides (AMPs) have to destroy or penetrate to fulfill their mission. Upon penetrating through the membrane, the peptides can further attack intracellular targets, in particular DNA. Studying the interaction of an antimicrobial peptide with a cell membrane and DNA holds keys to understanding its killing mechanisms. Commonly, these interactions are studied by using optical or scanning electron microscopy and appropriately labeled peptides. However, labeling can significantly affect the hydrophobicity, conformation, and size of the peptide, hence altering the interaction significantly. Here, we describe the use of atomic force microscopy (AFM) for a label-free study of the interactions of peptides with model membranes under physiological conditions and DNA as a possible intracellular target.
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Affiliation(s)
- Peter Fojan
- Department of Physics and Nanotechnology, Aalborg University, Skjernvej 4A, Aalborg, 9220, Denmark.
| | - Leonid Gurevich
- Department of Physics and Nanotechnology, Aalborg University, Skjernvej 4A, Aalborg, 9220, Denmark
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46
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Parikh N, Klimov DK. Inclusion of lipopeptides into the DMPC lipid bilayers prevents Aβ peptide insertion. Phys Chem Chem Phys 2017; 19:10087-10098. [DOI: 10.1039/c7cp01003f] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Lipopeptides prevent penetration of Alzheimer's Aβ peptides into lipid bilayers.
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Affiliation(s)
- Niyati Parikh
- School of Systems Biology
- George Mason University
- Manassas
- USA
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47
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Rai DK, Sharma VK, Anunciado D, O'Neill H, Mamontov E, Urban V, Heller WT, Qian S. Neutron Scattering Studies of the Interplay of Amyloid β Peptide(1-40) and An Anionic Lipid 1,2-dimyristoyl-sn-glycero-3-phosphoglycerol. Sci Rep 2016; 6:30983. [PMID: 27503057 PMCID: PMC4995599 DOI: 10.1038/srep30983] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2016] [Accepted: 07/05/2016] [Indexed: 12/19/2022] Open
Abstract
The interaction between lipid bilayers and Amyloid β peptide (Aβ) plays a critical role in proliferation of Alzheimer’s disease (AD). AD is expected to affect one in every 85 humans by 2050, and therefore, deciphering the interplay of Aβ and lipid bilayers at the molecular level is of profound importance. In this work, we applied an array of neutron scattering methods to study the structure and dynamics of Aβ(1–40) interacting 1,2-dimyristoyl-sn-glycero-3-phosphoglycerol (DMPG) bilayers. In the structural investigations of lipid bilayer’s response to Aβ binding, Small Angle Neutron Scattering and Neutron Membrane Diffraction revealed that the Aβ anchors firmly to the highly charged DMPG bilayers in the interfacial region between water and hydrocarbon chain, and it doesn’t penetrate deeply into the bilayer. This association mode is substantiated by the dynamics studies with high resolution Quasi-Elastic Neutron Scattering experiments, showing that the addition of Aβ mainly affects the slower lateral motion of lipid molecules, especially in the fluid phase, but not the faster internal motion. The results revealed that Aβ associates with the highly charged membrane in surface with limited impact on the structure, but the altered membrane dynamics could have more influence on other membrane processes.
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Affiliation(s)
- Durgesh K Rai
- Biology and Soft Matter Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
| | - Veerendra K Sharma
- Biology and Soft Matter Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
| | - Divina Anunciado
- Biology and Soft Matter Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
| | - Hugh O'Neill
- Biology and Soft Matter Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
| | - Eugene Mamontov
- Chemical and Engineering Materials Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
| | - Volker Urban
- Biology and Soft Matter Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
| | - William T Heller
- Biology and Soft Matter Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
| | - Shuo Qian
- Biology and Soft Matter Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
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48
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Lockhart C, Klimov DK. The Alzheimer's disease A β peptide binds to the anionic DMPS lipid bilayer. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2016; 1858:1118-28. [DOI: 10.1016/j.bbamem.2016.03.001] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/24/2015] [Revised: 02/26/2016] [Accepted: 03/01/2016] [Indexed: 11/24/2022]
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49
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Membrane binding of peptide models for early stages of amyloid formation: Lipid packing counts more than charge. Chem Phys Lipids 2016; 198:28-38. [DOI: 10.1016/j.chemphyslip.2016.02.010] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2015] [Revised: 02/04/2016] [Accepted: 02/27/2016] [Indexed: 11/17/2022]
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50
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Delgado DA, Doherty K, Cheng Q, Kim H, Xu D, Dong H, Grewer C, Qiang W. Distinct Membrane Disruption Pathways Are Induced by 40-Residue β-Amyloid Peptides. J Biol Chem 2016; 291:12233-44. [PMID: 27056326 DOI: 10.1074/jbc.m116.720656] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2016] [Indexed: 11/06/2022] Open
Abstract
Cellular membrane disruption induced by β-amyloid (Aβ) peptides has been considered one of the major pathological mechanisms for Alzheimer disease. Mechanistic studies of the membrane disruption process at a high-resolution level, on the other hand, are hindered by the co-existence of multiple possible pathways, even in simplified model systems such as the phospholipid liposome. Therefore, separation of these pathways is crucial to achieve an in-depth understanding of the Aβ-induced membrane disruption process. This study, which utilized a combination of multiple biophysical techniques, shows that the peptide-to-lipid (P:L) molar ratio is an important factor that regulates the selection of dominant membrane disruption pathways in the presence of 40-residue Aβ peptides in liposomes. Three distinct pathways (fibrillation with membrane content leakage, vesicle fusion, and lipid uptake through a temporarily stable ionic channel) become dominant in model liposome systems under specific conditions. These individual systems are characterized by both the initial states of Aβ peptides and the P:L molar ratio. Our results demonstrated the possibility to generate simplified Aβ-membrane model systems with a homogeneous membrane disruption pathway, which will benefit high-resolution mechanistic studies in the future. Fundamentally, the possibility of pathway selection controlled by P:L suggests that the driving forces for Aβ aggregation and Aβ-membrane interactions may be similar at the molecular level.
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Affiliation(s)
- Dennis A Delgado
- From the Department of Chemistry, State University of New York, Binghamton, New York 13902 and
| | - Katelynne Doherty
- From the Department of Chemistry, State University of New York, Binghamton, New York 13902 and
| | - Qinghui Cheng
- From the Department of Chemistry, State University of New York, Binghamton, New York 13902 and
| | - Hyeongeun Kim
- From the Department of Chemistry, State University of New York, Binghamton, New York 13902 and
| | - Dawei Xu
- the Department of Chemistry and Biomolecular Science, Clarkson University, Potsdam, New York 13699
| | - He Dong
- the Department of Chemistry and Biomolecular Science, Clarkson University, Potsdam, New York 13699
| | - Christof Grewer
- From the Department of Chemistry, State University of New York, Binghamton, New York 13902 and
| | - Wei Qiang
- From the Department of Chemistry, State University of New York, Binghamton, New York 13902 and
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