51
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Sanders HM, Jovcevski B, Marty MT, Pukala TL. Structural and mechanistic insights into amyloid-β and α-synuclein fibril formation and polyphenol inhibitor efficacy in phospholipid bilayers. FEBS J 2022; 289:215-230. [PMID: 34268903 PMCID: PMC8727495 DOI: 10.1111/febs.16122] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2020] [Revised: 06/11/2021] [Accepted: 07/15/2021] [Indexed: 01/03/2023]
Abstract
Under certain cellular conditions, functional proteins undergo misfolding, leading to a transition into oligomers which precede the formation of amyloid fibrils. Misfolding proteins are associated with neurodegenerative diseases such as Alzheimer's and Parkinson's diseases. While the importance of lipid membranes in misfolding and disease aetiology is broadly accepted, the influence of lipid membranes during therapeutic design has been largely overlooked. This study utilized a biophysical approach to provide mechanistic insights into the effects of two lipid membrane systems (anionic and zwitterionic) on the inhibition of amyloid-β 40 and α-synuclein amyloid formation at the monomer, oligomer and fibril level. Large unilamellar vesicles (LUVs) were shown to increase fibrillization and largely decrease the effectiveness of two well-known polyphenol fibril inhibitors, (-)-epigallocatechin gallate (EGCG) and resveratrol; however, use of immunoblotting and ion mobility mass spectrometry revealed this occurs through varying mechanisms. Oligomeric populations in particular were differentially affected by LUVs in the presence of resveratrol, an elongation phase inhibitor, compared to EGCG, a nucleation targeted inhibitor. Ion mobility mass spectrometry showed EGCG interacts with or induces more compact forms of monomeric protein typical of off-pathway structures; however, binding is reduced in the presence of LUVs, likely due to partitioning in the membrane environment. Competing effects of the lipids and inhibitor, along with reduced inhibitor binding in the presence of LUVs, provide a mechanistic understanding of decreased inhibitor efficacy in a lipid environment. Together, this study highlights that amyloid inhibitor design may be misguided if effects of lipid membrane composition and architecture are not considered during development.
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Affiliation(s)
- Henry M. Sanders
- Department of Chemistry, School of Physical Sciences, The University of Adelaide, Adelaide, SA 5005, Australia,Department of Chemistry and Biochemistry, University of Arizona, Tucson, Arizona 85721, United States
| | - Blagojce Jovcevski
- Department of Chemistry, School of Physical Sciences, The University of Adelaide, Adelaide, SA 5005, Australia
| | - Michael T. Marty
- Department of Chemistry and Biochemistry, University of Arizona, Tucson, Arizona 85721, United States
| | - Tara L. Pukala
- Department of Chemistry, School of Physical Sciences, The University of Adelaide, Adelaide, SA 5005, Australia,Correspondence: Tara L. Pukala: School of Physical Sciences, The University of Adelaide, Adelaide, SA 5005, Australia; ; Tel. +61 8 8313 5497
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52
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Cava DG, Vélez M. Supported Lipid Bilayers (SLBs) to Study Amyloid-Lipid Membrane Interactions with Atomic Force Microscopy. Methods Mol Biol 2022; 2538:109-116. [PMID: 35951296 DOI: 10.1007/978-1-0716-2529-3_8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Supported lipid bilayers (SLBs) are model membrane systems that can be used to study the interaction between amyloid fibers and membranes with atomic force microscopy (AFM). This chapter describes the preparation of SLBs on mica that can then be used as a substrate for fiber absorption. AFM can then be used to study the topography of the lipid-protein surface to study the evolution of the fibers, as well as the modifications on the membrane induced by their presence.
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Affiliation(s)
- Daniel G Cava
- Instituto de Catálisis y Petroleoquímica (CSIC), (Cantoblanco) Madrid, Spain
| | - Marisela Vélez
- Instituto de Catálisis y Petroleoquímica (CSIC), (Cantoblanco) Madrid, Spain.
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53
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Mrdenovic D, Lipkowski J, Pieta P. Analyzing Morphological Properties of Early-Stage Toxic Amyloid β Oligomers by Atomic Force Microscopy. Methods Mol Biol 2022; 2402:227-241. [PMID: 34854048 DOI: 10.1007/978-1-0716-1843-1_18] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Protein misfolding diseases, like Alzheimer's, Parkinson's, and Huntington's disease, are associated with misfolded protein aggregation. Alzheimer's disease is related to a progressive neuronal death induced by small amyloid β oligomers. Here, we describe the procedure to prepare and identify different types of small toxic amyloid β oligomers by atomic force microscopy (AFM).
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Affiliation(s)
- Dusan Mrdenovic
- Institute of Physical Chemistry, Polish Academy of Sciences, Warsaw, Poland
- Department of Chemistry, University of Guelph, Guelph, ON, Canada
| | - Jacek Lipkowski
- Department of Chemistry, University of Guelph, Guelph, ON, Canada
| | - Piotr Pieta
- Institute of Physical Chemistry, Polish Academy of Sciences, Warsaw, Poland.
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54
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Tang H, Li Y, Kakinen A, Andrikopoulos N, Sun Y, Kwak E, Davis TP, Ding F, Ke PC. Graphene quantum dots obstruct the membrane axis of Alzheimer's amyloid beta. Phys Chem Chem Phys 2021; 24:86-97. [PMID: 34878460 PMCID: PMC8771921 DOI: 10.1039/d1cp04246g] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Alzheimer's disease (AD) is a primary form of dementia with debilitating consequences, but no effective cure is available. While the pathophysiology of AD remains multifactorial, the aggregation of amyloid beta (Aβ) mediated by the cell membrane is known to be the cause for the neurodegeneration associated with AD. Here we examined the effects of graphene quantum dots (GQDs) on the obstruction of the membrane axis of Aβ in its three representative forms of monomers (Aβ-m), oligomers (Aβ-o), and amyloid fibrils (Aβ-f). Specifically, we determined the membrane fluidity of neuroblastoma SH-SY5Y cells perturbed by the Aβ species, especially by the most toxic Aβ-o, and demonstrated their recovery by GQDs using confocal fluorescence microscopy. Our computational data through discrete molecular dynamics simulations further revealed energetically favorable association of the Aβ species with the GQDs in overcoming peptide-peptide aggregation. Overall, this study positively implicated GQDs as an effective agent in breaking down the membrane axis of Aβ, thereby circumventing adverse downstream events and offering a potential therapeutic solution for AD.
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Affiliation(s)
- Huayuan Tang
- Department of Physics and Astronomy, Clemson University, Clemson, SC 29634, United States
| | - Yuhuan Li
- Liver Cancer Institute, Zhongshan Hospital, Key Laboratory of Carcinogenesis and Cancer Invasion, Ministry of Education, Fudan University, Shanghai, 200032, China,Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, VIC 3052, Australia
| | - Aleksandr Kakinen
- Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, Brisbane Qld 4072, Australia
| | - Nicholas Andrikopoulos
- Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, VIC 3052, Australia
| | - Yunxiang Sun
- School of Physical Science and Technology, Ningbo University, Ningbo 315211, China
| | - Eunbi Kwak
- Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, VIC 3052, Australia,The GBA National Institute for Nanotechnology Innovation, 136 Kaiyuan Avenue, Guangzhou, 510700, China
| | - Thomas P. Davis
- Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, VIC 3052, Australia,Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, Brisbane Qld 4072, Australia
| | - Feng Ding
- Department of Physics and Astronomy, Clemson University, Clemson, SC 29634, United States
| | - Pu Chun Ke
- Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, VIC 3052, Australia,Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, Brisbane Qld 4072, Australia,The GBA National Institute for Nanotechnology Innovation, 136 Kaiyuan Avenue, Guangzhou, 510700, China
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55
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Strazdaite S, Roeters SJ, Sakalauskas A, Sneideris T, Kirschner J, Pedersen KB, Schiøtt B, Jensen F, Weidner T, Smirnovas V, Niaura G. Interaction of Amyloid-β-(1-42) Peptide and Its Aggregates with Lipid/Water Interfaces Probed by Vibrational Sum-Frequency Generation Spectroscopy. J Phys Chem B 2021; 125:11208-11218. [PMID: 34597059 DOI: 10.1021/acs.jpcb.1c04882] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
In this study, we use surface-sensitive vibrational sum-frequency generation (VSFG) spectroscopy to investigate the interaction between model lipid monolayers and Aβ(1-42) in its monomeric and aggregated states. Combining VSFG with atomic force microscopy (AFM) and thioflavin T (ThT) fluorescence measurements, we found that only small aggregates with probably a β-hairpin-like structure adsorbed to the zwitterionic lipid monolayer (DOPC). In contrast, larger aggregates with an extended β-sheet structure adsorbed to a negatively charged lipid monolayer (DOPG). The adsorption of small, initially formed aggregates strongly destabilized both monolayers, but only the DOPC monolayer was completely disrupted. We showed that the intensity of the amide-II' band in achiral (SSP) and chiral (SPP) polarization combinations increased in time when Aβ(1-42) aggregates accumulated at the DOPG monolayer. Nevertheless, almost no adsorption of preformed mature fibrils to DOPG monolayers was detected. By performing spectral VSFG calculations, we revealed a clear correlation between the amide-II' signal and the degree of amyloid aggregates (e.g., oligomers or (proto)fibrils) of various Aβ(1-42) structures. The calculations showed that only structures with a significant amyloid β-sheet content have a strong amide-II' intensity, in line with previous Raman studies. The combination of the presented results substantiates the amide-II(') band as a legitimate amyloid marker.
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Affiliation(s)
- S Strazdaite
- Department of Organic Chemistry, Center for Physical Sciences and Technology, Sauletekio Ave. 3, Vilnius LT-10257, Lithuania
| | - S J Roeters
- Department of Chemistry, Aarhus University, Langelandsgade 140, 8000 Aarhus C, Denmark
| | - A Sakalauskas
- Institute of Biotechnology, Life Sciences Center, Vilnius University, Sauletekio 7, LT-10257 Vilnius, Lithuania
| | - T Sneideris
- Institute of Biotechnology, Life Sciences Center, Vilnius University, Sauletekio 7, LT-10257 Vilnius, Lithuania
| | - J Kirschner
- Institute of Solid State Physics, TU Wien, Wiedner Hauptstrasse 8-10, 1040 Vienna, Austria
| | - K B Pedersen
- Department of Chemistry, Aarhus University, Langelandsgade 140, 8000 Aarhus C, Denmark
| | - B Schiøtt
- Department of Chemistry, Aarhus University, Langelandsgade 140, 8000 Aarhus C, Denmark
| | - F Jensen
- Department of Chemistry, Aarhus University, Langelandsgade 140, 8000 Aarhus C, Denmark
| | - T Weidner
- Department of Chemistry, Aarhus University, Langelandsgade 140, 8000 Aarhus C, Denmark
| | - V Smirnovas
- Institute of Biotechnology, Life Sciences Center, Vilnius University, Sauletekio 7, LT-10257 Vilnius, Lithuania
| | - G Niaura
- Department of Organic Chemistry, Center for Physical Sciences and Technology, Sauletekio Ave. 3, Vilnius LT-10257, Lithuania
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56
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Gour N, Gazit E. Metabolite assemblies: A surprising extension to the amyloid hypothesis. Curr Opin Chem Biol 2021; 64:154-164. [PMID: 34482124 DOI: 10.1016/j.cbpa.2021.07.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Revised: 06/10/2021] [Accepted: 07/25/2021] [Indexed: 12/15/2022]
Abstract
The realization of the ability of metabolites to form self-assembled amyloid-like nanostructures was a surprising phenomenon. This discovery paved the way towards understanding the pathophysiology of the inborn error of metabolism disorders from a new perspective, relating them to amyloid-associated diseases that are characterized by the aggregation of proteins and polypeptides. Hence, a 'generic amyloid hypothesis' can be proposed. This theory implies that the formation of amyloid-like structures is a general phenomenon not limited to proteins and reflects a common etiology for both age-related amyloid-associated diseases and inborn error of metabolism disorders. Here, we present a comprehensive survey of the recent research related to metabolite amyloids including their structure formation through self-association, propagation, interactions, transmission, and their role in metabolic disorders and neurodegenerative diseases and their applications for the fabrication of novel materials which implicate metabolite assemblies as a surprising extension to the amyloid scheme.
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Affiliation(s)
- Nidhi Gour
- School of Science, Department of Chemistry, Indrashil University, Mehsana, Gujarat, 382740 India
| | - Ehud Gazit
- The Shmunis School of Biomedicine and Cancer Research, Tel Aviv University, Tel Aviv, 6997801, Israel; BLAVATNIK CENTER for Drug Discovery, Tel Aviv University, Tel Aviv, 6997801, Israel.
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57
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Madhu P, Das D, Mukhopadhyay S. Conformation-specific perturbation of membrane dynamics by structurally distinct oligomers of Alzheimer's amyloid-β peptide. Phys Chem Chem Phys 2021; 23:9686-9694. [PMID: 33908427 DOI: 10.1039/d0cp06456d] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The accumulation of toxic soluble oligomers of the amyloid-β peptide (Aβ) is a key step in the pathogenesis of Alzheimer's disease. There are mainly two conformationally distinct oligomers, namely, prefibrillar and fibrillar oligomers, that are recognized by conformation-specific antibodies, anti-amyloid oligomer antibody (A11) and anti-amyloid fibrillar antibody (OC), respectively. Previous studies have shown that the interaction of Aβ oligomers with the lipid membrane is one of the key mechanisms of toxicity produced by Aβ oligomers. However, the mechanism by which structurally distinct Aβ oligomers interact with the lipid membrane remains elusive. In this work, we dissect the molecular mechanism underlying the interaction of structurally distinct Aβ42 oligomers with the lipid membrane derived from the brain total lipid extract. Using picosecond time-resolved fluorescence spectroscopy, we show that the A11-positive Aβ42 oligomers undergo a membrane-induced conformational change that promotes the deeper immersion of these oligomers into the lipid hydrocarbon region and results in an increase in the membrane micro-viscosity. In sharp contrast, OC-positive Aβ42 oligomers interact with the lipid membrane via electrostatic interactions between the negatively-charged lipid headgroup and positively-charged residues of Aβ42 without perturbing the membrane dynamics. We show that the two structurally distinct Aβ42 oligomers demonstrating different interaction mechanisms with the lipid membrane eventually lead to the formation of typical amyloid fibrils. Our findings provide the mechanistic underpinning of the perturbation of lipid membranes by two conformationally distinct Aβ42 oligomers and can be of prime importance in designing anti-Alzheimer's therapeutic agents targeting Aβ-membrane interactions.
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Affiliation(s)
- Priyanka Madhu
- Centre for Protein Science Design and Engineering, Indian Institute of Science Education and Research (IISER), Mohali 140306, Punjab, India.
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58
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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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59
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Li Y, Tang H, Zhu H, Kakinen A, Wang D, Andrikopoulos N, Sun Y, Nandakumar A, Kwak E, Davis TP, Leong DT, Ding F, Ke PC. Ultrasmall Molybdenum Disulfide Quantum Dots Cage Alzheimer's Amyloid Beta to Restore Membrane Fluidity. ACS APPLIED MATERIALS & INTERFACES 2021; 13:29936-29948. [PMID: 34143617 PMCID: PMC8251662 DOI: 10.1021/acsami.1c06478] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
Alzheimer's disease (AD) is a major cause of dementia characterized by the overexpression of transmembrane amyloid precursor protein and its neurotoxic byproduct amyloid beta (Aβ). A small peptide of considerable hydrophobicity, Aβ is aggregation prone catalyzed by the presence of cell membranes, among other environmental factors. Accordingly, current AD mitigation strategies often aim at breaking down the Aβ-membrane communication, yet no data is available concerning the cohesive interplay of the three key entities of the cell membrane, Aβ, and its inhibitor. Using a lipophilic Laurdan dye and confocal fluorescence microscopy, we observed cell membrane perturbation and actin reorganization induced by Aβ oligomers but not by Aβ monomers or amyloid fibrils. We further revealed recovery of membrane fluidity by ultrasmall MoS2 quantum dots, also shown in this study as a potent inhibitor of Aβ amyloid aggregation. Using discrete molecular dynamics simulations, we uncovered the binding of MoS2 and Aβ monomers as mediated by hydrophilic interactions between the quantum dots and the peptide N-terminus. In contrast, Aβ oligomers and fibrils were surface-coated by the ultrasmall quantum dots in distinct testudo-like, reverse protein-corona formations to prevent their further association with the cell membrane and adverse effects downstream. This study offers a crucial new insight and a viable strategy for regulating the amyloid aggregation and membrane-axis of AD pathology with multifunctional nanomedicine.
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Affiliation(s)
- Yuhuan Li
- Liver Cancer Institute, Zhongshan Hospital, Key Laboratory of Carcinogenesis and Cancer Invasion, Ministry of Education, Fudan University, Shanghai, 200032, China
- Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, VIC 3052, Australia
| | - Huayuan Tang
- Department of Physics and Astronomy, Clemson University, Clemson, SC 29634, United States
| | - Houjuan Zhu
- National University of Singapore, Department of Chemical and Biomolecular Engineering, 4 Engineering Drive 4, Singapore 117585, Singapore
| | - Aleksandr Kakinen
- Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, Brisbane Qld 4072, Australia
| | - Di Wang
- School of Life Sciences, Jilin University, Changchun 130012, China
| | - Nicholas Andrikopoulos
- Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, VIC 3052, Australia
| | - Yunxiang Sun
- School of Physical Science and Technology, Ningbo University, Ningbo 315211, China
| | - Aparna Nandakumar
- Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, VIC 3052, Australia
| | - Eunbi Kwak
- Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, VIC 3052, Australia
| | - Thomas P. Davis
- Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, VIC 3052, Australia
- Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, Brisbane Qld 4072, Australia
| | - David Tai Leong
- National University of Singapore, Department of Chemical and Biomolecular Engineering, 4 Engineering Drive 4, Singapore 117585, Singapore
| | - Feng Ding
- Department of Physics and Astronomy, Clemson University, Clemson, SC 29634, United States
| | - Pu Chun Ke
- Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, VIC 3052, Australia
- Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, Brisbane Qld 4072, Australia
- The GBA National Institute for Nanotechnology Innovation, 136 Kaiyuan Avenue, Guangzhou, 510700, China
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60
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Andrade S, Loureiro JA, Pereira MC. The Role of Amyloid β-Biomembrane Interactions in the Pathogenesis of Alzheimer's Disease: Insights from Liposomes as Membrane Models. Chemphyschem 2021; 22:1547-1565. [PMID: 34086399 DOI: 10.1002/cphc.202100124] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Revised: 05/10/2021] [Indexed: 02/06/2023]
Abstract
The aggregation and deposition of amyloid β (Aβ) peptide onto neuronal cells, with consequent cellular membrane perturbation, are central to the pathogenesis of Alzheimer's disease (AD). Substantial evidence reveals that biological membranes play a key role in this process. Thus, elucidating the mechanisms by which Aβ interacts with biomembranes and becomes neurotoxic is fundamental to developing effective therapies for this devastating progressive disease. However, the structural basis behind such interactions is not fully understood, largely due to the complexity of natural membranes. In this context, lipid biomembrane models provide a simplified way to mimic the characteristics and composition of membranes. Aβ-biomembrane interactions have been extensively investigated applying artificial membrane models to elucidate the molecular mechanisms underlying the AD pathogenesis. This review summarizes the latest findings on this field using liposomes as biomembrane model, as they are considered the most promising 3D model. The current challenges and future directions are discussed.
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Affiliation(s)
- Stéphanie Andrade
- LEPABE - Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465, Porto, Portugal
| | - Joana Angélica Loureiro
- LEPABE - Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465, Porto, Portugal
| | - Maria Carmo Pereira
- LEPABE - Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465, Porto, Portugal
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61
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Sen N, Hause G, Binder WH. Membrane Anchored Polymers Modulate Amyloid Fibrillation. Macromol Rapid Commun 2021; 42:e2100120. [PMID: 33987913 DOI: 10.1002/marc.202100120] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2021] [Revised: 04/26/2021] [Indexed: 12/24/2022]
Abstract
The nucleating role of cellular membrane components, such as lipid moieties on amyloid beta (Aβ1-40 ) fibrillation, has been reported in recent years. The influence of conjugates fabricated from lipid anchors (cholesterol, diacylglycerol) and hydrophilic polymers on Aβ1-40 fibrillation is reported here, aiming to understand the impact of polymers cloud point temperature (Tcp ) and its hydrophobic tails on the amyloid fibrillation. Novel lipid-polymer conjugates, consisting of poly(oligo(ethylene glycol)m acrylates) and hydrophobic groups (diacylglyceryl-, cholesteryl-, octyl-, decyl-, hexadecyl-) as anchors are synthesized using reversible addition-fragmentation chain transfer (RAFT) polymerization, allowing to tune the hydrophilic-hydrophobic profile of the conjugates by varying both, the degree of polymerization (n) and number of ethylene glycol units (m) in their side chain. The impact of these conjugates on Aβ1-40 fibrillation is investigated via in vitro kinetic studies and transmission electron microscopy (TEM). Hydrophobic lipid-anchors are significantly delaying fibrillation (both lag- and half times), observing similar fibrillar structures via TEM when compared to native Aβ1-40 . Other hydrophobic end groups are also delaying fibrillation of Aβ1-40 , irrespective of their "n" and "m," whereas more hydrophilic polymers (both with longer ethylene glycol-sidechains, m = 3 for octyl, decyl and m = 5 for cholesterol) are only marginally inhibited fibrillation.
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Affiliation(s)
- Newton Sen
- Chair of Macromolecular Chemistry, Faculty of Natural Science II, Von-Danckelmann-Platz 4, Institute of Chemistry, Martin-Luther University Halle-Wittenberg, Halle (Saale), D-06120, Germany
| | - Gerd Hause
- Biocenter, Martin-Luther University Halle-Wittenberg, Weinbergweg 22, Halle (Saale), D-06120, Germany
| | - Wolfgang H Binder
- Chair of Macromolecular Chemistry, Faculty of Natural Science II, Von-Danckelmann-Platz 4, Institute of Chemistry, Martin-Luther University Halle-Wittenberg, Halle (Saale), D-06120, Germany
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62
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Gu L, Guo Z. Lipid membranes induce structural conversion from amyloid oligomers to fibrils. Biochem Biophys Res Commun 2021; 557:122-126. [PMID: 33862455 DOI: 10.1016/j.bbrc.2021.03.174] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2021] [Accepted: 03/31/2021] [Indexed: 12/16/2022]
Abstract
Formation of amyloid oligomers and fibrils underlies the pathogenesis of a number of neurodegenerative diseases such as Alzheimer's. One mechanism of action by which Aβ aggregates cause neuronal toxicity is through interactions with cellular membranes. Aβ aggregates have been shown to disrupt membrane integrity via pore formation, membrane thinning, or lipid extraction. At the same time, lipid membranes also affect the rate of Aβ aggregation and remodel pre-formed Aβ fibrils. Here we show that Aβ42 globulomers, a type of well-characterized and stable Aβ oligomers, convert to amyloid fibrils in the presence of DOPC liposomes. Electron paramagnetic resonance studies show that the fibrils converted from Aβ42 globulomers adopt the same structure as fibrils formed directly from monomers. Our results suggest that the interactions between Aβ oligomers and cellular membranes are dynamic. By converting Aβ oligomers to fibrils, the lipid membrane can reduce the membrane-disrupting activities caused by these oligomers. Modulation of Aβ-membrane interactions as a therapeutic strategy should take into account the dynamic nature of these interactions.
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Affiliation(s)
- Lei Gu
- Department of Neurology, Brain Research Institute, Molecular Biology Institute, University of California, Los Angeles, CA, 90095, USA
| | - Zhefeng Guo
- Department of Neurology, Brain Research Institute, Molecular Biology Institute, University of California, Los Angeles, CA, 90095, USA.
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63
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Ammendolia DA, Bement WM, Brumell JH. Plasma membrane integrity: implications for health and disease. BMC Biol 2021; 19:71. [PMID: 33849525 PMCID: PMC8042475 DOI: 10.1186/s12915-021-00972-y] [Citation(s) in RCA: 93] [Impact Index Per Article: 31.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2020] [Accepted: 02/01/2021] [Indexed: 12/12/2022] Open
Abstract
Plasma membrane integrity is essential for cellular homeostasis. In vivo, cells experience plasma membrane damage from a multitude of stressors in the extra- and intra-cellular environment. To avoid lethal consequences, cells are equipped with repair pathways to restore membrane integrity. Here, we assess plasma membrane damage and repair from a whole-body perspective. We highlight the role of tissue-specific stressors in health and disease and examine membrane repair pathways across diverse cell types. Furthermore, we outline the impact of genetic and environmental factors on plasma membrane integrity and how these contribute to disease pathogenesis in different tissues.
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Affiliation(s)
- Dustin A Ammendolia
- Cell Biology Program, Hospital for Sick Children, 686 Bay Street PGCRL, Toronto, ON, M5G 0A4, Canada.,Department of Molecular Genetics, University of Toronto, Toronto, ON, M5S 1A1, Canada
| | - William M Bement
- Center for Quantitative Cell Imaging and Department of Integrative Biology, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - John H Brumell
- Cell Biology Program, Hospital for Sick Children, 686 Bay Street PGCRL, Toronto, ON, M5G 0A4, Canada. .,Department of Molecular Genetics, University of Toronto, Toronto, ON, M5S 1A1, Canada. .,Institute of Medical Science, University of Toronto, Toronto, ON, M5S 1A1, Canada. .,SickKids IBD Centre, Hospital for Sick Children, Toronto, ON, M5G 0A4, Canada.
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64
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Tian Y, Liang R, Kumar A, Szwedziak P, Viles JH. 3D-visualization of amyloid-β oligomer interactions with lipid membranes by cryo-electron tomography. Chem Sci 2021; 12:6896-6907. [PMID: 34123318 PMCID: PMC8153238 DOI: 10.1039/d0sc06426b] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Amyloid-β (Aβ) assemblies have been shown to bind to lipid bilayers. This can disrupt membrane integrity and cause a loss of cellular homeostasis, that triggers a cascade of events leading to Alzheimer's disease. However, molecular mechanisms of Aβ cytotoxicity and how the different assembly forms interact with the membrane remain enigmatic. Here we use cryo-electron tomography (cryoET) to obtain three-dimensional nano-scale images of various Aβ assembly types and their interaction with liposomes. Aβ oligomers and curvilinear protofibrils bind extensively to the lipid vesicles, inserting and carpeting the upper-leaflet of the bilayer. Aβ oligomers concentrate at the interface of vesicles and form a network of Aβ-linked liposomes, while crucially, monomeric and fibrillar Aβ have relatively little impact on the membrane. Changes to lipid membrane composition highlight a significant role for GM1-ganglioside in promoting Aβ-membrane interactions. The different effects of Aβ assembly forms observed align with the highlighted cytotoxicity reported for Aβ oligomers. The wide-scale incorporation of Aβ oligomers and curvilinear protofibrils into the lipid bilayer suggests a mechanism by which membrane integrity is lost. Cryo-electron tomography 3D imaging of amyloid-β oligomers carpeting the surface of lipid bilayers in near native conditions.![]()
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Affiliation(s)
- Yao Tian
- School of Biological and Chemical Sciences, Queen Mary University of London Mile End Road London E1 4NS UK
| | - Ruina Liang
- School of Biological and Chemical Sciences, Queen Mary University of London Mile End Road London E1 4NS UK
| | - Amit Kumar
- School of Biological and Chemical Sciences, Queen Mary University of London Mile End Road London E1 4NS UK
| | - Piotr Szwedziak
- Laboratory of Structural Cell Biology, Centre of New Technologies, University of Warsaw 02-097 Warsaw Poland .,ReMedy-International Research Agenda Unit, Centre of New Technologies, University of Warsaw 02-097 Warsaw Poland
| | - John H Viles
- School of Biological and Chemical Sciences, Queen Mary University of London Mile End Road London E1 4NS UK
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65
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Gonzalez-Garcia M, Fusco G, De Simone A. Membrane Interactions and Toxicity by Misfolded Protein Oligomers. Front Cell Dev Biol 2021; 9:642623. [PMID: 33791300 PMCID: PMC8006268 DOI: 10.3389/fcell.2021.642623] [Citation(s) in RCA: 38] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Accepted: 02/08/2021] [Indexed: 01/13/2023] Open
Abstract
The conversion of otherwise soluble proteins into insoluble amyloid aggregates is associated with a range of neurodegenerative disorders, including Alzheimer’s and Parkinson’s diseases, as well as non-neuropathic conditions such as type II diabetes and systemic amyloidoses. It is increasingly evident that the most pernicious species among those forming during protein aggregation are small prefibrillar oligomers. In this review, we describe the recent progress in the characterization of the cellular and molecular interactions by toxic misfolded protein oligomers. A fundamental interaction by these aggregates involves biological membranes, resulting in two major model mechanisms at the onset of the cellular toxicity. These include the membrane disruption model, resulting in calcium imbalance, mitochondrial dysfunction and intracellular reactive oxygen species, and the direct interaction with membrane proteins, leading to the alteration of their native function. A key challenge remains in the characterization of transient interactions involving heterogeneous protein aggregates. Solving this task is crucial in the quest of identifying suitable therapeutic approaches to suppress the cellular toxicity in protein misfolding diseases.
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Affiliation(s)
- Mario Gonzalez-Garcia
- Department of Life Sciences, Imperial College London, South Kensington, United Kingdom
| | - Giuliana Fusco
- Department of Chemistry, Centre for Misfolding Diseases, University of Cambridge, Cambridge, United Kingdom
| | - Alfonso De Simone
- Department of Life Sciences, Imperial College London, South Kensington, United Kingdom.,Department of Pharmacy, University of Naples Federico II, Naples, Italy
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66
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Mrdenovic D, Zarzycki P, Majewska M, Pieta IS, Nowakowski R, Kutner W, Lipkowski J, Pieta P. Inhibition of Amyloid β-Induced Lipid Membrane Permeation and Amyloid β Aggregation by K162. ACS Chem Neurosci 2021; 12:531-541. [PMID: 33478212 PMCID: PMC7877724 DOI: 10.1021/acschemneuro.0c00754] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Accepted: 01/07/2021] [Indexed: 01/17/2023] Open
Abstract
Alzheimer's disease (AD) is characterized by progressive neurodegeneration associated with amyloid β (Aβ) peptide aggregation. The aggregation of Aβ monomers (AβMs) leads to the formation of Aβ oligomers (AβOs), the neurotoxic Aβ form, capable of permeating the cell membrane. Here, we investigated the effect of a fluorene-based active drug candidate, named K162, on both Aβ aggregation and AβO toxicity toward the bilayer lipid membrane (BLM). Electrochemical impedance spectroscopy (EIS), atomic force microscopy (AFM), and molecular dynamics (MD) were employed to show that K162 inhibits AβOs-induced BLM permeation, thus preserving BLM integrity. In the presence of K162, only shallow defects on the BLM surface were formed. Apparently, K162 modifies Aβ aggregation by bypassing the formation of toxic AβOs, and only nontoxic AβMs, dimers (AβDs), and fibrils (AβFs) are produced. Unlike other Aβ toxicity inhibitors, K162 preserves neurologically beneficial AβMs. This unique K162 inhibition mechanism provides an alternative AD therapeutic strategy that could be explored in the future.
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Affiliation(s)
- Dusan Mrdenovic
- Institute
of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland
- Department
of Chemistry, University of Guelph, 50 Stone Road East, Guelph, Ontario N1G 2W1, Canada
| | - Piotr Zarzycki
- Energy Geosciences
Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, California 94720, United States
| | - Marta Majewska
- Institute
of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland
| | - Izabela S. Pieta
- Institute
of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland
| | - Robert Nowakowski
- Institute
of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland
| | - Wlodzimierz Kutner
- Institute
of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland
- Faculty
of Mathematics and Natural Sciences, School of Sciences, Cardinal Stefan Wyszynski University in Warsaw, Wóycickiego 1/3, 01-815 Warsaw, Poland
| | - Jacek Lipkowski
- Department
of Chemistry, University of Guelph, 50 Stone Road East, Guelph, Ontario N1G 2W1, Canada
| | - Piotr Pieta
- Institute
of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland
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67
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Plasma membrane integrity in health and disease: significance and therapeutic potential. Cell Discov 2021; 7:4. [PMID: 33462191 PMCID: PMC7813858 DOI: 10.1038/s41421-020-00233-2] [Citation(s) in RCA: 88] [Impact Index Per Article: 29.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Accepted: 10/23/2020] [Indexed: 12/13/2022] Open
Abstract
Maintenance of plasma membrane integrity is essential for normal cell viability and function. Thus, robust membrane repair mechanisms have evolved to counteract the eminent threat of a torn plasma membrane. Different repair mechanisms and the bio-physical parameters required for efficient repair are now emerging from different research groups. However, less is known about when these mechanisms come into play. This review focuses on the existence of membrane disruptions and repair mechanisms in both physiological and pathological conditions, and across multiple cell types, albeit to different degrees. Fundamentally, irrespective of the source of membrane disruption, aberrant calcium influx is the common stimulus that activates the membrane repair response. Inadequate repair responses can tip the balance between physiology and pathology, highlighting the significance of plasma membrane integrity. For example, an over-activated repair response can promote cancer invasion, while the inability to efficiently repair membrane can drive neurodegeneration and muscular dystrophies. The interdisciplinary view explored here emphasises the widespread potential of targeting plasma membrane repair mechanisms for therapeutic purposes.
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68
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Li Y, Tang H, Andrikopoulos N, Javed I, Cecchetto L, Nandakumar A, Kakinen A, Davis TP, Ding F, Ke PC. The membrane axis of Alzheimer's nanomedicine. ADVANCED NANOBIOMED RESEARCH 2021; 1:2000040. [PMID: 33748816 PMCID: PMC7971452 DOI: 10.1002/anbr.202000040] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Alzheimer's disease (AD) is a major neurological disorder impairing its carrier's cognitive function, memory and lifespan. While the development of AD nanomedicine is still nascent, the field is evolving into a new scientific frontier driven by the diverse physicochemical properties and theranostic potential of nanomaterials and nanocomposites. Characteristic to the AD pathology is the deposition of amyloid plaques and tangles of amyloid beta (Aβ) and tau, whose aggregation kinetics may be curbed by nanoparticle inhibitors via sequence-specific targeting or nonspecific interactions with the amyloidogenic proteins. As literature implicates cell membrane as a culprit in AD pathogenesis, here we summarize the membrane axis of AD nanomedicine and present a new rationale that the field development may greatly benefit from harnessing our existing knowledge of Aβ-membrane interaction, nanoparticle-membrane interaction and Aβ-nanoparticle interaction.
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Affiliation(s)
- Yuhuan Li
- Zhongshan Hospital, Fudan University, 111 Yixueyuan Rd, Xuhui District, Shanghai, 200032, China
- ARC Centre of Excellence in Convergent Bio-Nano Science and Technology, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, VIC 3052, Australia
| | - Huayuan Tang
- Department of Physics and Astronomy, Clemson University, Clemson, SC 29634, United States
| | - Nicholas Andrikopoulos
- ARC Centre of Excellence in Convergent Bio-Nano Science and Technology, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, VIC 3052, Australia
| | - Ibrahim Javed
- Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, Brisbane, Qld 4072, Australia
| | - Luca Cecchetto
- ARC Centre of Excellence in Convergent Bio-Nano Science and Technology, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, VIC 3052, Australia
- Department of Chemical and Pharmaceutical Science, University of Trieste, Via Licio Giorgieri 1, 34127 Trieste, Italy
| | - Aparna Nandakumar
- ARC Centre of Excellence in Convergent Bio-Nano Science and Technology, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, VIC 3052, Australia
| | - Aleksandr Kakinen
- Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, Brisbane, Qld 4072, Australia
| | - Thomas P. Davis
- ARC Centre of Excellence in Convergent Bio-Nano Science and Technology, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, VIC 3052, Australia
- Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, Brisbane, Qld 4072, Australia
| | - Feng Ding
- Department of Physics and Astronomy, Clemson University, Clemson, SC 29634, United States
| | - Pu Chun Ke
- Zhongshan Hospital, Fudan University, 111 Yixueyuan Rd, Xuhui District, Shanghai, 200032, China
- ARC Centre of Excellence in Convergent Bio-Nano Science and Technology, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, VIC 3052, Australia
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69
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Lukiw WJ, Arceneaux L, Li W, Bond T, Zhao Y. Gastrointestinal (GI)-Tract Microbiome Derived Neurotoxins and their Potential Contribution to Inflammatory Neurodegeneration in Alzheimer's Disease (AD). JOURNAL OF ALZHEIMER'S DISEASE & PARKINSONISM 2021; 11:525. [PMID: 34457996 PMCID: PMC8395586] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The human gastrointestinal (GI)-tract microbiome is a rich, complex and dynamic source of microorganisms that possess a staggering diversity and complexity. Importantly there is a significant variability in microbial complexity even amongst healthy individuals-this has made it difficult to link specific microbial abundance patterns with age-related neurological disease. GI-tract commensal microorganisms are generally beneficial to human metabolism and immunity, however enterotoxigenic forms of microbes possess significant potential to secrete what are amongst the most neurotoxic and pro-inflammatory biopolymers known. These include toxic glycolipids such as lipopolysaccharide (LPS), enterotoxins, microbial-derived amyloids and small non-coding RNA. One major microbial species of the GI-tract microbiome, about ~100-fold more abundant than Escherichia coli in deep GI-tract regions is Bacteroides fragilis, an anaerobic, rod-shaped Gram-negative bacterium. B. fragilis can secrete: (i) a particularly potent, pro-inflammatory and unique LPS subtype (BF-LPS); and (ii) a zinc-metalloproteinase known as B. fragilis-toxin (BFT) or fragilysin. Ongoing studies indicate that BF-LPS and/or BFT disrupt paracellular-and transcellular-barriers by cleavage of intercellular-proteins resulting in 'leaky' barriers. These barriers: (i) become defective and more penetrable with aging and disease; and (ii) permit entry of microbiome-derived neurotoxins into the systemic-circulation from which they next transit the blood-brain barrier and gain access to the CNS. Here LPS accumulates and significantly alters homeostatic patterns of gene expression. The affinity of LPS for neuronal nuclei is significantly enhanced in the presence of amyloid beta 42 (Aβ42) peptides. Recent research on the appearance of the brain thanatomicrobiome at the time of death and the increasing likelihood of a complex brain microbiome are reviewed and discussed. This paper will also highlight some recent advances in this extraordinary research area that links the pro-inflammatory exudates of the GI-tract microbiome with innate-immune disturbances and inflammatory-signaling within the CNS with reference to Alzheimer's disease (AD) wherever possible.
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Affiliation(s)
- Walter J. Lukiw
- LSU Neuroscience Center, Louisiana State University Health
Sciences Center, New Orleans, LA, United States,Department of Ophthalmology, LSU Health Sciences Center,
New Orleans, LA, United States,Department of Neurology, Louisiana State University Health
Sciences Center, New Orleans, LA, United States,Corresponding author: Dr. Walter J. Lukiw, LSU
Neuroscience Center, Louisiana State University Health Sciences Center, New
Orleans, LA, United States,
| | - Lisa Arceneaux
- LSU Neuroscience Center, Louisiana State University Health
Sciences Center, New Orleans, LA, United States
| | - Wenhong Li
- LSU Neuroscience Center, Louisiana State University Health
Sciences Center, New Orleans, LA, United States,Department of Pharmacology, School of Pharmacy, Jiangxi
University of Traditional Chinese Medicine (TCM), Nanchang, China
| | - Taylor Bond
- LSU Neuroscience Center, Louisiana State University Health
Sciences Center, New Orleans, LA, United States
| | - Yuhai Zhao
- LSU Neuroscience Center, Louisiana State University Health
Sciences Center, New Orleans, LA, United States,Department of Anatomy and Cell Biology, Louisiana State
University, New Orleans, LA, United States
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70
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Parodi‐Rullán R, Ghiso J, Cabrera E, Rostagno A, Fossati S. Alzheimer's amyloid β heterogeneous species differentially affect brain endothelial cell viability, blood-brain barrier integrity, and angiogenesis. Aging Cell 2020; 19:e13258. [PMID: 33155752 PMCID: PMC7681048 DOI: 10.1111/acel.13258] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Revised: 09/02/2020] [Accepted: 09/19/2020] [Indexed: 01/05/2023] Open
Abstract
Impaired clearance in the Alzheimer's Disease (AD) brain is key in the formation of Aβ parenchymal plaques and cerebrovascular deposits known as cerebral amyloid angiopathy (CAA), present in >80% of AD patients and ~50% of non-AD elderly subjects. Aβ deposits are highly heterogeneous, containing multiple fragments mostly derived from catabolism of Aβ40/Aβ42, which exhibit dissimilar aggregation properties. Remarkably, the role of these physiologically relevant Aβ species in cerebrovascular injury and their impact in vascular pathology is unknown. We sought to understand how heterogeneous Aβ species affect cerebral endothelial health and assess whether their diverse effects are associated with the peptides aggregation propensities. We analyzed cerebral microvascular endothelial cell (CMEC) viability, blood-brain barrier (BBB) permeability, and angiogenesis, all relevant aspects of brain microvascular dysfunction. We found that Aβ peptides and fragments exerted differential effects on cerebrovascular pathology. Peptides forming mostly oligomeric structures induced CMEC apoptosis, whereas fibrillar aggregates increased BBB permeability without apoptotic effects. Interestingly, all Aβ species tested inhibited angiogenesis in vitro. These data link the biological effects of the heterogeneous Aβ peptides to their primary structure and aggregation, strongly suggesting that the composition of amyloid deposits influences clinical aspects of the AD vascular pathology. As the presence of predominant oligomeric structures in proximity of the vessel walls may lead to CMEC death and induction of microhemorrhages, fibrillar amyloid is likely responsible for increased BBB permeability and associated neurovascular dysfunction. These results have the potential to unveil more specific therapeutic targets and clarify the multifactorial nature of AD.
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Affiliation(s)
- Rebecca Parodi‐Rullán
- Alzheimer's Center at Temple Lewis Katz School of Medicine Temple University Philadelphia PA USA
| | - Jorge Ghiso
- Department of Pathology New York University School of Medicine New York NY USA
- Department of Psychiatry New York University School of Medicine New York NY USA
| | - Erwin Cabrera
- Department of Pathology New York University School of Medicine New York NY USA
| | - Agueda Rostagno
- Department of Pathology New York University School of Medicine New York NY USA
| | - Silvia Fossati
- Alzheimer's Center at Temple Lewis Katz School of Medicine Temple University Philadelphia PA USA
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71
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Mondal S, Vashi Y, Ghosh P, Roy D, Barthakur M, Kumar S, Iyer PK. Amyloid Targeting "Artificial Chaperone" Impairs Oligomer Mediated Neuronal Damage and Mitochondrial Dysfunction Associated with Alzheimer's Disease. ACS Chem Neurosci 2020; 11:3277-3287. [PMID: 32941009 DOI: 10.1021/acschemneuro.0c00387] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Alzheimer's disease (AD) is an irreversible memory disorder associated with multiple neuropathological events including amyloid aggregation that triggers oxidative stress and mitochondrial dysfunction in humans. Herein, a new artificial chaperone, benzimidazole functionalized polyfluorene (PFBZ) is reported to efficiently sequester toxic amyloid beta (Aβ) by binding at their 'amyloidogenic domain' (Aβ16-21) with unprecedented selectivity and prevent amyloid-mediated neuronal damage in a wild-type (WT) mouse model. An accurate dose of PFBZ chaperone successfully attenuated an amyloid triggered internal hemorrhage and pyknosis in the cerebral cortex of WT mice. The structural advantage of the polymer results in an efficient Cu(II) chelation arresting a redox cycle to prevent reactive oxygen species (ROS) generation and protect mitochondria from ROS mediated damage. This was further evidenced by caspase activation and mitochondrial membrane potential (MMP) biomarkers and was complemented by brain histology and electron microscopy data which revealed that the PFBZ chaperone provided a protective coating over the amyloid surface and resists from interacting with cell membrane and prevents inducing toxicity. This conjugated polymer artificial chaperone-based nanodrug showed exceptional properties such as its multipotent and highly biocompatible nature, the first of its kind with specific amyloid (Aβ16-21) targeting behavior, bioimaging, and BBB permeability with a potential to suppress amyloid triggered neurotoxicity implicated in numerous human disorders through a rare synergistic mechanism.
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Affiliation(s)
- Subrata Mondal
- Department of Chemistry, Indian Institute of Technology Guwahati, Guwahati 781039, Assam, India
| | - Yoya Vashi
- Department of Bioscience and Bioengineering, Indian Institute of Technology Guwahati, Guwahati 781039, Assam, India
| | - Priyam Ghosh
- Department of Chemistry, Indian Institute of Technology Guwahati, Guwahati 781039, Assam, India
| | - Dhrubajyoti Roy
- Department of Chemistry, Indian Institute of Technology Guwahati, Guwahati 781039, Assam, India
| | - Manash Barthakur
- Department of Zoology, Pub Kamrup College, Baihata Chariali, Kamrup 781381, Assam, India
| | - Sachin Kumar
- Department of Bioscience and Bioengineering, Indian Institute of Technology Guwahati, Guwahati 781039, Assam, India
| | - Parameswar Krishnan Iyer
- Department of Chemistry, Indian Institute of Technology Guwahati, Guwahati 781039, Assam, India
- Center for Nanotechnology, Indian Institute of Technology Guwahati, Guwahati 781039, Assam, India
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72
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Puig E, Tolchard J, Riera A, Carulla N. Somatostatin, an In Vivo Binder to Aβ Oligomers, Binds to βPFO Aβ(1-42) Tetramers. ACS Chem Neurosci 2020; 11:3358-3365. [PMID: 32915532 DOI: 10.1021/acschemneuro.0c00470] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Somatostatin (SST14) is strongly related to Alzheimer's disease (AD), as its levels decline during aging, it regulates the proteolytic degradation of the amyloid beta peptide (Aβ), and it binds to Aβ oligomers in vivo. Recently, the 3D structure of a membrane-associated β-sheet pore-forming tetramer (βPFOAβ(1-42) tetramer) has been reported. Here, we show that SST14 binds selectively to the βPFOAβ(1-42) tetramer with a KD value of ∼40 μM without binding to monomeric Aβ(1-42). Specific NMR chemical shift perturbations, observed during titration of SST14, define a binding site in the βPFOAβ(1-42) tetramer and are in agreement with a 2:1 stoichiometry determined by both native mass spectroscopy and isothermal titration calorimetry. These results enabled us to perform driven docking and model the binding mode for the interaction. The present study provides additional evidence on the relation between SST14 and the amyloid cascade and positions the βPFOAβ(1-42) tetramer as a relevant aggregation form of Aβ and as a potential target for AD.
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Affiliation(s)
- Eduard Puig
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology (BIST), Baldiri Reixac 10, Barcelona 08028, Spain
- CBMN (UMR 5248), University of Bordeaux−CNRS−IPB, Institut Européen de Chimie et Biologie, 2 rue Escarpit, Pessac 33600, France
| | - James Tolchard
- CBMN (UMR 5248), University of Bordeaux−CNRS−IPB, Institut Européen de Chimie et Biologie, 2 rue Escarpit, Pessac 33600, France
| | - Antoni Riera
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology (BIST), Baldiri Reixac 10, Barcelona 08028, Spain
- Departament de Química Inorgànica i Orgànica, Universitat de Barcelona, Martí i Franqués 1, Barcelona 08028, Spain
| | - Natàlia Carulla
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology (BIST), Baldiri Reixac 10, Barcelona 08028, Spain
- CBMN (UMR 5248), University of Bordeaux−CNRS−IPB, Institut Européen de Chimie et Biologie, 2 rue Escarpit, Pessac 33600, France
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73
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Qiang W, Doherty KE, Klees LM, Tobin-Miyaji Y. Time-Dependent Lipid Dynamics, Organization and Peptide-Lipid Interaction in Phospholipid Bilayers with Incorporated β-Amyloid Oligomers. J Phys Chem Lett 2020; 11:8329-8336. [PMID: 32931283 PMCID: PMC7647725 DOI: 10.1021/acs.jpclett.0c01967] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Nonfibrillar β-amyloid (Aβ) oligomers are considered as major neurotoxic species in the pathology of Alzheimer's disease. The presence of Aβ oligomers was shown to cause membrane disruptions in a broad range of model systems. However, the molecular basis of such a disruption process remains unknown. We previously demonstrated that membrane-incorporated 40-residue Aβ (Aβ40) oligomers could form coaggregates with phospholipids. This process occurred more rapidly than the fibrillization of Aβ40 and led to more severe membrane disruption. The present study probes the time-dependent changes in lipid dynamics, bilayer structures, and peptide-lipid interactions along the time course of the oligomer-induced membrane disruption, using solid-state NMR spectroscopy. Our results suggest the presence of certain intermediate states with phospholipid molecules entering the C-terminal hydrogen-bonding networks of the Aβ40 oligomeric cores. This work provides insights on the molecular mechanisms of Aβ40-oligomer-induced membrane disruption.
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Affiliation(s)
- Wei Qiang
- Department of Chemistry, Binghamton University, State University of New York, Binghamton, New York 13902
| | - Katelynne E. Doherty
- Department of Chemistry, Binghamton University, State University of New York, Binghamton, New York 13902
| | - Lukas M. Klees
- Department of Chemistry, Binghamton University, State University of New York, Binghamton, New York 13902
| | - Yuto Tobin-Miyaji
- Department of Chemistry, Binghamton University, State University of New York, Binghamton, New York 13902
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74
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Vadukul DM, Maina M, Franklin H, Nardecchia A, Serpell LC, Marshall KE. Internalisation and toxicity of amyloid-β 1-42 are influenced by its conformation and assembly state rather than size. FEBS Lett 2020; 594:3490-3503. [PMID: 32871611 DOI: 10.1002/1873-3468.13919] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Revised: 07/30/2020] [Accepted: 08/19/2020] [Indexed: 01/18/2023]
Abstract
Amyloid fibrils found in plaques in Alzheimer's disease (AD) brains are composed of amyloid-β peptides. Oligomeric amyloid-β 1-42 (Aβ42) is thought to play a critical role in neurodegeneration in AD. Here, we determine how size and conformation affect neurotoxicity and internalisation of Aβ42 assemblies using biophysical methods, immunoblotting, toxicity assays and live-cell imaging. We report significant cytotoxicity of Aβ42 oligomers and their internalisation into neurons. In contrast, Aβ42 fibrils show reduced internalisation and no toxicity. Sonicating Aβ42 fibrils generates species similar in size to oligomers but remains nontoxic. The results suggest that Aβ42 oligomers have unique properties that underlie their neurotoxic potential. Furthermore, we show that incubating cells with Aβ42 oligomers for 24 h is sufficient to trigger irreversible neurotoxicity.
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Affiliation(s)
- Devkee M Vadukul
- Dementia Research group, Sussex Neuroscience, School of Life Sciences, University of Sussex, Falmer, E Sussex, UK.,CEMO-Alzheimer Dementia group, Institute of Neuroscience, Université catholique de Louvain, Brussels, Belgium
| | - Mahmoud Maina
- Dementia Research group, Sussex Neuroscience, School of Life Sciences, University of Sussex, Falmer, E Sussex, UK.,College of Medical Sciences, Yobe State University, Nigeria
| | - Hannah Franklin
- Dementia Research group, Sussex Neuroscience, School of Life Sciences, University of Sussex, Falmer, E Sussex, UK
| | - Astrid Nardecchia
- Dementia Research group, Sussex Neuroscience, School of Life Sciences, University of Sussex, Falmer, E Sussex, UK
| | - Louise C Serpell
- Dementia Research group, Sussex Neuroscience, School of Life Sciences, University of Sussex, Falmer, E Sussex, UK
| | - Karen E Marshall
- Dementia Research group, Sussex Neuroscience, School of Life Sciences, University of Sussex, Falmer, E Sussex, UK
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75
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Feuillie C, Lambert E, Ewald M, Azouz M, Henry S, Marsaudon S, Cullin C, Lecomte S, Molinari M. High Speed AFM and NanoInfrared Spectroscopy Investigation of Aβ 1-42 Peptide Variants and Their Interaction With POPC/SM/Chol/GM1 Model Membranes. Front Mol Biosci 2020; 7:571696. [PMID: 33033718 PMCID: PMC7510551 DOI: 10.3389/fmolb.2020.571696] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Accepted: 08/17/2020] [Indexed: 12/14/2022] Open
Abstract
Due to an aging population, neurodegenerative diseases such as Alzheimer's disease (AD) have become a major health issue. In the case of AD, Aβ1 - 42 peptides have been identified as one of the markers of the disease with the formation of senile plaques via their aggregation, and could play a role in memory impairment and other tragic syndromes associated with the disease. Many studies have shown that not only the morphology and structure of Aβ1 - 42 peptide assembly are playing an important role in the formation of amyloid plaques, but also the interactions between Aβ1 - 42 and the cellular membrane are crucial regarding the aggregation processes and toxicity of the amyloid peptides. Despite the increasing amount of information on AD associated amyloids and their toxicity, the molecular mechanisms involved still remain unclear and require in-depth investigation at the local scale to clearly decipher the role of the sequence of the amyloid peptides, of their secondary structures, of their oligomeric states, and of their interactions with lipid membranes. In this original study, through the use of Atomic Force Microscopy (AFM) related-techniques, high-speed AFM and nanoInfrared AFM, we tried to unravel at the nanoscale the link between aggregation state, structure and interaction with membranes in the amyloid/membrane interaction. Using three mutants of Aβ peptides, L34T, oG37C, and WT Aβ1 - 42 peptides, with differences in morphology, structure and assembly process, as well as model lipidic membranes whose composition and structure allow interactions with the peptides, our AFM study coupling high spatial and temporal resolution and nanoscale structure information clearly evidences a local correlation between the secondary structure of the peptides, their fibrillization kinetics and their interactions with model membranes. Membrane disruption is associated to small transient oligomeric entities in the early stages of aggregation that strongly interact with the membrane, and present an antiparallel β-sheet secondary structure. The strong effect on membrane integrity that exists when these oligomeric Aβ1 - 42 peptides interact with membranes of a particular composition could be a lead for therapeutic studies.
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Affiliation(s)
- Cecile Feuillie
- CBMN, CNRS UMR 5248, IPB, Université de Bordeaux, Pessac, France
| | - Eleonore Lambert
- LRN EA 4682, Université de Reims Champagne-Ardenne, Reims, France
| | - Maxime Ewald
- LRN EA 4682, Université de Reims Champagne-Ardenne, Reims, France
| | - Mehdi Azouz
- CBMN, CNRS UMR 5248, IPB, Université de Bordeaux, Pessac, France.,Department of Chemistry, Université de Montréal, Montreal, QC, Canada
| | - Sarah Henry
- CBMN, CNRS UMR 5248, IPB, Université de Bordeaux, Pessac, France
| | - Sophie Marsaudon
- CBMN, CNRS UMR 5248, IPB, Université de Bordeaux, Pessac, France
| | | | - Sophie Lecomte
- CBMN, CNRS UMR 5248, IPB, Université de Bordeaux, Pessac, France
| | - Michael Molinari
- CBMN, CNRS UMR 5248, IPB, Université de Bordeaux, Pessac, France
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76
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Vane EW, He S, Maibaum L, Nath A. Rapid Formation of Peptide/Lipid Coaggregates by the Amyloidogenic Seminal Peptide PAP 248-286. Biophys J 2020; 119:924-938. [PMID: 32814060 PMCID: PMC7474197 DOI: 10.1016/j.bpj.2020.07.029] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2020] [Revised: 07/14/2020] [Accepted: 07/29/2020] [Indexed: 12/27/2022] Open
Abstract
Protein/lipid coassembly is an understudied phenomenon that is important to the function of antimicrobial peptides as well as the pathological effects of amyloid. Here, we study the coassembly process of PAP248-286, a seminal peptide that displays both amyloid-forming and antimicrobial activity. PAP248-286 is a peptide fragment of prostatic acid phosphatase and has been reported to form amyloid fibrils, known as semen-derived enhancer of viral infection (SEVI), that enhance the viral infectivity of human immunodeficiency virus. We find that in addition to forming amyloid, PAP248-286 much more readily assembles with lipid vesicles into peptide/lipid coaggregates that resemble amyloid fibrils in some important ways but are a distinct species. The formation of these PAP248-286/lipid coaggregates, which we term "messicles," is controlled by the peptide:lipid (P:L) ratio and by the lipid composition. The optimal P:L ratio is around 1:10, and at least 70% anionic lipid is required for coaggregate formation. Once formed, messicles are not disrupted by subsequent changes in P:L ratio. We propose that messicles form through a polyvalent assembly mechanism, in which a critical surface density of PAP248-286 on liposomes enables peptide-mediated particle bridging into larger species. Even at ∼50-fold lower PAP248-286 concentrations, messicles form at least 10-fold faster than amyloid fibrils. It is therefore possible that some or all of the biological activities assigned to SEVI, the amyloid form of PAP248-286, could instead be attributed to a PAP248-286/lipid coaggregate. More broadly speaking, this work could provide a potential framework for the discovery and characterization of nonamyloid peptide/lipid coaggregates by other amyloid-forming proteins and antimicrobial peptides.
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Affiliation(s)
- Eleanor W Vane
- Department of Medicinal Chemistry, University of Washington, Seattle, Washington; Biological Physics, Structure and Design Program, University of Washington, Seattle, Washington
| | - Shushan He
- Department of Chemistry, University of Washington, Seattle, Washington
| | - Lutz Maibaum
- Department of Chemistry, University of Washington, Seattle, Washington
| | - Abhinav Nath
- Department of Medicinal Chemistry, University of Washington, Seattle, Washington; Biological Physics, Structure and Design Program, University of Washington, Seattle, Washington.
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77
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Direct measurement of lipid membrane disruption connects kinetics and toxicity of Aβ42 aggregation. Nat Struct Mol Biol 2020; 27:886-891. [DOI: 10.1038/s41594-020-0471-z] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2019] [Accepted: 06/25/2020] [Indexed: 11/08/2022]
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78
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Proteotoxicity and Neurodegenerative Diseases. Int J Mol Sci 2020; 21:ijms21165646. [PMID: 32781742 PMCID: PMC7460676 DOI: 10.3390/ijms21165646] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2020] [Revised: 08/01/2020] [Accepted: 08/04/2020] [Indexed: 02/07/2023] Open
Abstract
Neurodegenerative diseases are a major burden for our society, affecting millions of people worldwide. A main goal of past and current research is to enhance our understanding of the mechanisms underlying proteotoxicity, a common theme among these incurable and debilitating conditions. Cell proteome alteration is considered to be one of the main driving forces that triggers neurodegeneration, and unraveling the biological complexity behind the affected molecular pathways constitutes a daunting challenge. This review summarizes the current state on key processes that lead to cellular proteotoxicity in Alzheimer's disease, Parkinson's disease, Huntington's disease, and amyotrophic lateral sclerosis, providing a comprehensive landscape of recent literature. A foundational understanding of how proteotoxicity affects disease etiology and progression may provide essential insight towards potential targets amenable of therapeutic intervention.
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79
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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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80
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Huang YR, Liu RT. The Toxicity and Polymorphism of β-Amyloid Oligomers. Int J Mol Sci 2020; 21:E4477. [PMID: 32599696 PMCID: PMC7352971 DOI: 10.3390/ijms21124477] [Citation(s) in RCA: 83] [Impact Index Per Article: 20.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Revised: 06/19/2020] [Accepted: 06/20/2020] [Indexed: 12/26/2022] Open
Abstract
It is widely accepted that β-amyloid oligomers (Aβos) play a key role in the progression of Alzheimer's disease (AD) by inducing neuron damage and cognitive impairment, but Aβos are highly heterogeneous in their size, structure and cytotoxicity, making the corresponding studies tough to carry out. Nevertheless, a number of studies have recently made remarkable progress in the describing the characteristics and pathogenicity of Aβos. We here review the mechanisms by which Aβos exert their neuropathogenesis for AD progression, including receptor binding, cell membrane destruction, mitochondrial damage, Ca2+ homeostasis dysregulation and tau pathological induction. We also summarize the characteristics and pathogenicity such as the size, morphology and cytotoxicity of dimers, trimers, Aβ*56 and spherical oligomers, and suggest that Aβos may play a different role at different phases of AD pathogenesis, resulting in differential consequences on neuronal synaptotoxicity and survival. It is warranted to investigate the temporal sequence of Aβos in AD human brain and examine the relationship between different Aβos and cognitive impairment.
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Affiliation(s)
- Ya-ru Huang
- State Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China;
- School of Chemical Engineering, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Rui-tian Liu
- State Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China;
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81
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Menon S, Sengupta N, Das P. Nanoscale Interplay of Membrane Composition and Amyloid Self-Assembly. J Phys Chem B 2020; 124:5837-5846. [DOI: 10.1021/acs.jpcb.0c03796] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Sneha Menon
- Physical Chemistry Division, CSIR-National Chemical Laboratory, Pune 411008, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Neelanjana Sengupta
- Department of Biological Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur 741246, India
| | - Payel Das
- IBM Thomas J. Watson Research Center, Yorktown Heights, New York 10598, United States
- Applied Physics and Applied Math Department, Columbia University, New York, New York 10027, United States
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82
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Cox SJ, Lam B, Prasad A, Marietta HA, Stander NV, Joel JG, Sahoo BR, Guo F, Stoddard AK, Ivanova MI, Ramamoorthy A. High-Throughput Screening at the Membrane Interface Reveals Inhibitors of Amyloid-β. Biochemistry 2020; 59:2249-2258. [DOI: 10.1021/acs.biochem.0c00328] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Sarah J. Cox
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Brian Lam
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Ajay Prasad
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Hannah A. Marietta
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Nicholas V. Stander
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Joseph G. Joel
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Bikash R. Sahoo
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Fucheng Guo
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Andrea K. Stoddard
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Magdalena I. Ivanova
- Department of Neurology, University of Michigan, Ann Arbor, Michigan 48109, United States
- Program in Biophysics, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Ayyalusamy Ramamoorthy
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, United States
- Program in Biophysics, University of Michigan, Ann Arbor, Michigan 48109, United States
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83
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Future avenues for Alzheimer's disease detection and therapy: liquid biopsy, intracellular signaling modulation, systems pharmacology drug discovery. Neuropharmacology 2020; 185:108081. [PMID: 32407924 DOI: 10.1016/j.neuropharm.2020.108081] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2019] [Revised: 03/01/2020] [Accepted: 03/30/2020] [Indexed: 12/20/2022]
Abstract
When Alzheimer's disease (AD) disease-modifying therapies will be available, global healthcare systems will be challenged by a large-scale demand for clinical and biological screening. Validation and qualification of globally accessible, minimally-invasive, and time-, cost-saving blood-based biomarkers need to be advanced. Novel pathophysiological mechanisms (and related candidate biomarkers) - including neuroinflammation pathways (TREM2 and YKL-40), axonal degeneration (neurofilament light chain protein), synaptic dysfunction (neurogranin, synaptotagmin, α-synuclein, and SNAP-25) - may be integrated into an expanding pathophysiological and biomarker matrix and, ultimately, integrated into a comprehensive blood-based liquid biopsy, aligned with the evolving ATN + classification system and the precision medicine paradigm. Liquid biopsy-based diagnostic and therapeutic algorithms are increasingly employed in Oncology disease-modifying therapies and medical practice, showing an enormous potential for AD and other brain diseases as well. For AD and other neurodegenerative diseases, newly identified aberrant molecular pathways have been identified as suitable therapeutic targets and are currently investigated by academia/industry-led R&D programs, including the nerve-growth factor pathway in basal forebrain cholinergic neurons, the sigma1 receptor, and the GTPases of the Rho family. Evidence for a clinical long-term effect on cognitive function and brain health span of cholinergic compounds, drug candidates for repositioning programs, and non-pharmacological multidomain interventions (nutrition, cognitive training, and physical activity) is developing as well. Ultimately, novel pharmacological paradigms, such as quantitative systems pharmacology-based integrative/explorative approaches, are gaining momentum to optimize drug discovery and accomplish effective pathway-based strategies for precision medicine. This article is part of the special issue on 'The Quest for Disease-Modifying Therapies for Neurodegenerative Disorders'.
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84
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Kravenska Y, Nieznanska H, Nieznanski K, Lukyanetz E, Szewczyk A, Koprowski P. The monomers, oligomers, and fibrils of amyloid-β inhibit the activity of mitoBK Ca channels by a membrane-mediated mechanism. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2020; 1862:183337. [PMID: 32380169 DOI: 10.1016/j.bbamem.2020.183337] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/28/2019] [Revised: 04/25/2020] [Accepted: 04/28/2020] [Indexed: 02/08/2023]
Abstract
A causative agent of Alzheimer's disease (AD) is a short amphipathic peptide called amyloid beta (Aβ). Aβ monomers undergo structural changes leading to their oligomerization or fibrillization. The monomers as well as all aggregated forms of Aβ, i.e., oligomers, and fibrils, can bind to biological membranes, thereby modulating membrane mechanical properties. It is also known that some isoforms of the large-conductance calcium-activated potassium (BKCa) channel, including the mitochondrial BKCa (mitoBKCa) channel, respond to mechanical changes in the membrane. Here, using the patch-clamp technique, we investigated the impact of full-length Aβ (Aβ1-42) and its fragment, Aβ25-35, on the activity of mitoBKCa channels. We found that all forms of Aβ inhibited the activity of the mitoBKCa channel in a concentration-dependent manner. Since monomers, oligomers, and fibrils of Aβ exhibit different molecular characteristics and structures, we hypothesized that the inhibition was not due to direct peptide-protein interactions but rather to membrane-binding of the Aβ peptides. Our findings supported this hypothesis by showing that Aβ peptides block mitoBKCa channels irrespective of the side of the membrane to which they are applied. In addition, we found that the enantiomeric peptide, D-Aβ1-42, demonstrated similar inhibitory activity towards mitoBKCa channels. As a result, we proposed a general model in which all Aβ forms i.e., monomers, oligomers, and amyloid fibrils, contribute to the progression of AD by exerting a modulatory effect on mechanosensitive membrane components.
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Affiliation(s)
- Yevheniia Kravenska
- Laboratory of Intracellular Ion Channels, Nencki Institute of Experimental Biology PAS, Pasteura str. 3, Warsaw 02-093, Poland; Department of Biophysics of Ion Channels, Bogomoletz Institute of Physiology NASU, Bogomoletz str. 4, Kyiv 01-024, Ukraine.
| | - Hanna Nieznanska
- Laboratory of Electron Microscopy, Nencki Institute of Experimental Biology PAS, Pasteura str. 3, Warsaw 02-093, Poland
| | - Krzysztof Nieznanski
- Laboratory of Molecular Basis of Cell Motility, Nencki Institute of Experimental Biology PAS, Pasteura str. 3, Warsaw 02-093, Poland
| | - Elena Lukyanetz
- Department of Biophysics of Ion Channels, Bogomoletz Institute of Physiology NASU, Bogomoletz str. 4, Kyiv 01-024, Ukraine
| | - Adam Szewczyk
- Laboratory of Intracellular Ion Channels, Nencki Institute of Experimental Biology PAS, Pasteura str. 3, Warsaw 02-093, Poland
| | - Piotr Koprowski
- Laboratory of Intracellular Ion Channels, Nencki Institute of Experimental Biology PAS, Pasteura str. 3, Warsaw 02-093, Poland
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85
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Esmaili M, Tancowny BP, Wang X, Moses A, Cortez LM, Sim VL, Wille H, Overduin M. Native nanodiscs formed by styrene maleic acid copolymer derivatives help recover infectious prion multimers bound to brain-derived lipids. J Biol Chem 2020; 295:8460-8469. [PMID: 32358064 DOI: 10.1074/jbc.ra119.012348] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Revised: 04/14/2020] [Indexed: 11/06/2022] Open
Abstract
Prions are lipidated proteins that interact with endogenous lipids and metal ions. They also assemble into multimers and propagate into the infectious scrapie form known as PrPSc The high-resolution structure of the infectious PrPSc state remains unknown, and its analysis largely relies on detergent-based preparations devoid of endogenous ligands. Here we designed polymers that allow isolation of endogenous membrane:protein assemblies in native nanodiscs without exposure to conventional detergents that destabilize protein structures and induce fibrillization. A set of styrene-maleic acid (SMA) polymers including a methylamine derivative facilitated gentle release of the infectious complexes for resolution of multimers, and a thiol-containing version promoted crystallization. Polymer extraction from brain homogenates from Syrian hamsters infected with Hyper prions and WT mice infected with Rocky Mountain Laboratories prions yielded infectious prion nanoparticles including oligomers and microfilaments bound to lipid vesicles. Lipid analysis revealed the brain phospholipids that associate with prion protofilaments, as well as those that are specifically enriched in prion assemblies captured by the methylamine-modified copolymer. A comparison of the infectivity of PrPSc attached to SMA lipid particles in mice and hamsters indicated that these amphipathic polymers offer a valuable tool for high-yield production of intact, detergent-free prions that retain in vivo activity. This native prion isolation method provides an avenue for producing relevant prion:lipid targets and potentially other proteins that form multimeric assemblies and fibrils on membranes.
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Affiliation(s)
- Mansoore Esmaili
- Department of Biochemistry, University of Alberta, Edmonton, Alberta, Canada
| | - Brian P Tancowny
- Department of Biochemistry, University of Alberta, Edmonton, Alberta, Canada.,Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada
| | - Xiongyao Wang
- Department of Biochemistry, University of Alberta, Edmonton, Alberta, Canada.,Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada
| | - Audric Moses
- Lipidomics Core Facility, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta, Canada
| | - Leonardo M Cortez
- Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada.,Division of Neurology, Department of Medicine, Centre for Prions and Protein Folding Diseases, and Neuroscience and Mental Health Institute, University of Alberta, Edmonton, Alberta, Canada
| | - Valerie L Sim
- Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada.,Division of Neurology, Department of Medicine, Centre for Prions and Protein Folding Diseases, and Neuroscience and Mental Health Institute, University of Alberta, Edmonton, Alberta, Canada
| | - Holger Wille
- Department of Biochemistry, University of Alberta, Edmonton, Alberta, Canada .,Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada
| | - Michael Overduin
- Department of Biochemistry, University of Alberta, Edmonton, Alberta, Canada
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86
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Adhikari R, Yang M, Saikia N, Dutta C, Alharbi WFA, Shan Z, Pandey R, Tiwari A. Acetylation of Aβ42 at Lysine 16 Disrupts Amyloid Formation. ACS Chem Neurosci 2020; 11:1178-1191. [PMID: 32207962 PMCID: PMC7605495 DOI: 10.1021/acschemneuro.0c00069] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
The residue lysine 28 (K28) is known to form an important salt bridge that stabilizes the Aβ amyloid structure, and acetylation of lysine 28 (K28Ac) slows the Aβ42 fibrillization rate but does not affect fibril morphology. On the other hand, acetylation of lysine 16 (K16Ac) residue greatly diminishes the fibrillization property of Aβ42 peptide and also affects its toxicity. This is due to the fact that lysine 16 acetylated amyloid beta peptide forms amorphous aggregates instead of amyloid fibrils. This is likely a result of increased hydrophobicity of the K16-A21 region due to K16 acetylation, as confirmed by molecular dynamic simulation studies. The calculated results show that the hydrophobic patches of aggregates from acetylated peptides were different when compared to wild-type (WT) peptide. K16Ac and double acetylated (KKAc) peptide aggregates show significantly higher cytotoxicity compared to the WT or K28Ac peptide aggregates alone. However, the heterogeneous mixture of WT and acetylated Aβ42 peptide aggregates exhibited higher free radical formation as well as cytotoxicity, suggesting dynamic interactions between different species could be a critical contributor to Aβ pathology.
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Affiliation(s)
- Rashmi Adhikari
- Department of Chemistry, Michigan Technological University, Houghton, Michigan 49931, United States
| | - Mu Yang
- Department of Chemistry, Michigan Technological University, Houghton, Michigan 49931, United States
| | - Nabanita Saikia
- Department of Physics, Michigan Technological University, Houghton, Michigan 49931, United States
| | - Colina Dutta
- Department of Chemistry, Michigan Technological University, Houghton, Michigan 49931, United States
| | - Wafa F A Alharbi
- Department of Biological Sciences, Michigan Technological University, Houghton, Michigan 49931, United States
| | - Zhiying Shan
- Department of Kinesiology and Integrative Physiology, Michigan Technological University, Houghton, Michigan 49931, United States
| | - Ravindra Pandey
- Department of Physics, Michigan Technological University, Houghton, Michigan 49931, United States
| | - Ashutosh Tiwari
- Department of Chemistry, Michigan Technological University, Houghton, Michigan 49931, United States
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87
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Oren O, Ben Zichri S, Taube R, Jelinek R, Papo N. Aβ42 Double Mutant Inhibits Aβ42-Induced Plasma and Mitochondrial Membrane Disruption in Artificial Membranes, Isolated Organs, and Intact Cells. ACS Chem Neurosci 2020; 11:1027-1037. [PMID: 32155047 DOI: 10.1021/acschemneuro.9b00638] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Destabilization of plasma and inner mitochondrial membranes by extra- and intracellular amyloid β peptide (Aβ42) aggregates may lead to dysregulated calcium flux through the plasma membrane, mitochondrial-mediated apoptosis, and neuronal cell death in patients with Alzheimer's disease. In the current study, experiments performed with artificial membranes, isolated mitochondria, and neuronal cells allowed us to understand the mechanism by which a nonaggregating Aβ42 double mutant (designated Aβ42DM) exerts its neuroprotective effects. Specifically, we showed that Aβ42DM protected neuronal cells from Aβ42-induced accumulation of toxic intracellular levels of calcium and from apoptosis. Aβ42DM also inhibited Aβ42-induced mitochondrial membrane potential depolarization in the cells and abolished the Aβ42-mediated decrease in cytochrome c oxidase activity in purified mitochondrial particles. These results can be explained in terms of the amelioration by Aβ42DM of Aβ42-mediated changes in membrane fluidity in DOPC and cardiolipin/DOPC phospholipid vesicles, mimicking plasma and mitochondrial membranes, respectively. These observations are also in agreement with the inhibition by Aβ42DM of phospholipid-induced conformational changes in Aβ42 and with the fact that, unlike Aβ42, the Aβ42-Aβ42DM complex could not permeate into cells but instead remained attached to the cell membrane. Although most of the Aβ42DM molecules were localized on the cell membrane, some penetrated into the cytosol in an Aβ42-independent process, and, unlike Aβ42, did not form intracellular inclusion bodies. Overall, we provide a mechanistic explanation for the inhibitory activity of Aβ42DM against Aβ42-induced membrane permeability and cell toxicity and provide confirmatory evidence for its protective function in neuronal cells.
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Affiliation(s)
- Ofek Oren
- The Shraga Segal Department of Microbiology, Immunology and Genetics, Faculty of Health Sciences, Ben-Gurion University of the Negev, P.O. Box 653, Beer Sheva 84105, Israel
| | - Shani Ben Zichri
- Department of Chemistry, Ben-Gurion University, P.O. Box 653, Beer Sheva 84105, Israel
| | - Ran Taube
- The Shraga Segal Department of Microbiology, Immunology and Genetics, Faculty of Health Sciences, Ben-Gurion University of the Negev, P.O. Box 653, Beer Sheva 84105, Israel
| | - Raz Jelinek
- Department of Chemistry, Ben-Gurion University, P.O. Box 653, Beer Sheva 84105, Israel
| | - Niv Papo
- Avram and Stella Goldstein-Goren Department of Biotechnology Engineering and the National Institute of Biotechnology in the Negev, Ben-Gurion University of the Negev, P.O. Box 653, Beer Sheva 84105, Israel
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88
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Coarse-grained MD simulations reveal beta-amyloid fibrils of various sizes bind to interfacial liquid-ordered and liquid-disordered regions in phase separated lipid rafts with diverse membrane-bound conformational states. Biophys Chem 2020; 260:106355. [PMID: 32179374 DOI: 10.1016/j.bpc.2020.106355] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Revised: 02/23/2020] [Accepted: 02/29/2020] [Indexed: 12/16/2022]
Abstract
The membrane binding behaviors of beta-amyloid fibrils, dimers to pentamers, from solution to lipid raft surfaces, were investigated using coarse-grained (CG) MD simulations. Our CG rafts contain phospholipid, cholesterol (with or without tail- or headgroup modifications), and with or without asymmetrically distributed monosialotetrahexosylganglioside (GM1). All rafts exhibited liquid-ordered (Lo), liquid-disordered (Ld), and interfacial Lo/Ld (Lod) domains, with domain sizes depending on cholesterol structure. For rafts without GM1, all fibrils bound to the Lod domains. Specifically, dimer fibrils bound exclusively via the C-terminal, while larger fibrils could bind via other protein regions. Interestingly, a membrane-inserted state was detected for a trimer fibril in a raft with tail-group modified cholesterol. For rafts containing GM1, fibrils bound either to the GM1-clusters, with numerous membrane-bound conformations, or to the non-GM1-containing-Lod domains via the C-terminal. Our results indicate beta-amyloid fibrils bind to Lod domains or GM1, with diversified membrane-bound conformations, in structurally heterogeneous lipid membranes.
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89
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CRANAD-28: A Robust Fluorescent Compound for Visualization of Amyloid Beta Plaques. Molecules 2020; 25:molecules25040863. [PMID: 32079064 PMCID: PMC7070309 DOI: 10.3390/molecules25040863] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Revised: 02/14/2020] [Accepted: 02/14/2020] [Indexed: 11/16/2022] Open
Abstract
CRANAD-28, a difluoroboron curcumin analogue, has been demonstrated in earlier reports to successfully label amyloid beta (Aβ) plaques for imaging both ex vivo and in vivo. CRANAD-28's imaging brightness, ability to penetrate the blood brain barrier, and low toxicity make the compound a potentially potent imaging tool in Alzheimer's research. In this study, the Aβ-labeling ability of CRANAD-28 was investigated in further detail using histological staining to assess different criteria, including stained Aβ plaque brightness, Aβ plaque size, and Aβ plaque number count. The results of this study demonstrated CRANAD-28 to be superior across all criteria assessed. Furthermore, CRANAD-28 and IBA-1 antibody were used to label Aβ-plaques and microglia respectively. Statistical analysis with Spearman regression revealed a statistically significant negative correlation between the size of labeled Aβ plaques and surrounding microglia density. This finding provides interesting insight into Aβ plaque and microglia dynamism in AD pathology and corroborates the findings of previous studies. In addition, we found that CRANAD-28 provided distinct spectral signatures for Aβs in the core and periphery of the plaques. Based on the study's results, CRANAD-28 could be considered as an alternative standard for imaging Aβ-plaques in future research studies.
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90
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Ngo ST, Nguyen PH, Derreumaux P. Impact of A2T and D23N Mutations on Tetrameric Aβ42 Barrel within a Dipalmitoylphosphatidylcholine Lipid Bilayer Membrane by Replica Exchange Molecular Dynamics. J Phys Chem B 2020; 124:1175-1182. [DOI: 10.1021/acs.jpcb.9b11881] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- Son Tung Ngo
- Laboratory of Theoretical and Computational Biophysics, Ton Duc Thang University, Ho Chi Minh City 33000, Vietnam
- Faculty of Applied Sciences, Ton Duc Thang University, Ho Chi Minh City 33000, Vietnam
| | - Phuong H. Nguyen
- CNRS, Université de Paris, UPR 9080, Laboratoire de Biochimie Théorique, 13 rue Pierre et Marie Curie, F-75005 Paris, France
- Institut de Biologie Physico-Chimique, Fondation Edmond de Rothschild, PSL Research University, Paris 75005, France
| | - Philippe Derreumaux
- Laboratory of Theoretical Chemistry, Ton Duc Thang University, Ho Chi Minh City 33000, Vietnam
- Faculty of Pharmacy, Ton Duc Thang University, Ho Chi Minh City 33000, Vietnam
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91
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Ngo ST, Nguyen PH, Derreumaux P. Stability of Aβ11-40 Trimers with Parallel and Antiparallel β-Sheet Organizations in a Membrane-Mimicking Environment by Replica Exchange Molecular Dynamics Simulation. J Phys Chem B 2020; 124:617-626. [PMID: 31931566 DOI: 10.1021/acs.jpcb.9b10982] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The aggregation of the amyloid (Aβ) peptide of 39-43 amino acids into plaques is observed in the brain of Alzheimer's disease (AD) patients, but the mechanisms underlying the neurotoxicity of Aβ oligomers are still elusive. One suggested initial mechanism is related to the implications of amyloid membrane interactions, but characterization of these assemblies is challenging by experimental means. In this study, we have explored the stability of a trimer of Aβ11-40 in parallel and antiparallel β-sheet structures for the wild-type sequence and its F20W mutant in a dipalmitoylphosphatidylcholine membrane using atomistic replica exchange molecular dynamic simulations. We show that both the U-shape organization and the assembly of β-hairpins are maintained in the membrane and are resistant to the mutation F20W. In contrast the models are destabilized by the F19P mutation. Overall, our results indicate that these two assemblies represent minimal seeds or nuclei for the formation of either amyloid fibrils, a variety of β-barrel pores, or various aggregates for many Aβ sequences in a membrane-mimicking environment.
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Affiliation(s)
- Son Tung Ngo
- Laboratory of Theoretical and Computational Biophysics , Ton Duc Thang University , Ho Chi Minh City , Vietnam.,Faculty of Applied Sciences , Ton Duc Thang University , Ho Chi Minh City , Vietnam
| | - Phuong H Nguyen
- Laboratoire de Biochimie Théorique , UPR 9080, CNRS, Université de Paris , 13 rue Pierre et Marie Curie , 75005 , Paris , France.,Institut de Biologie Physico-Chimique-Fondation Edmond de Rothschild, PSL Research University , 75005 Paris , France
| | - Philippe Derreumaux
- Laboratory of Theoretical Chemistry , Ton Duc Thang University , Ho Chi Minh City , Vietnam.,Faculty of Pharmacy , Ton Duc Thang University , Ho Chi Minh City , Vietnam
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92
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Liyanage SI, Weaver DF. Misfolded proteins as a therapeutic target in Alzheimer's disease. ADVANCES IN PROTEIN CHEMISTRY AND STRUCTURAL BIOLOGY 2020; 118:371-411. [PMID: 31928732 DOI: 10.1016/bs.apcsb.2019.08.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
For decades, Alzheimer's Disease (AD) was defined as a disorder of protein misfolding and aggregation. In particular, the extracellular peptide fragment: amyloid-β (Aβ), and the intracellular microtubule-associated protein: tau, were thought to initiate a neurodegenerative cascade which culminated in AD's progressive loss of memory and executive function. As such, both proteins became the focus of intense scrutiny, and served as the principal pathogenic target for hundreds of clinical trials. However, with varying efficacy, none of these investigations produced a disease-modifying therapy - offering patients with AD little recourse aside from transient, symptomatic medications. The near universal failure of clinical trials is unprecedented for a major research discipline. In part, this has motivated an increasing skepticism of the relevance of protein misfolding to AD's etiology. Several recent observations, principally the presence of significant protein pathologies in non-demented seniors, have lent credence to an apparent cursory role for Aβ and tau. Herein, we review both Aβ and tau, examining the processes from their biosynthesis to their pathogenesis and evaluate their vulnerability to medicinal intervention. We further attempt to reconcile the apparent failure of trials with the potential these targets hold. Ultimately, we seek to answer if protein misfolding is a viable platform in the pursuit of a disease-arresting strategy for AD.
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Affiliation(s)
- S Imindu Liyanage
- Krembil Research Institute, University Health Network, Toronto, ON, Canada
| | - Donald F Weaver
- Krembil Research Institute, University Health Network, Toronto, ON, Canada; Departments of Medicine (Neurology), Chemistry and Pharmaceutical Sciences, University of Toronto, Toronto, ON, Canada
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93
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Lukiw WJ, Li W, Bond T, Zhao Y. Facilitation of Gastrointestinal (GI) Tract Microbiome-Derived Lipopolysaccharide (LPS) Entry Into Human Neurons by Amyloid Beta-42 (Aβ42) Peptide. Front Cell Neurosci 2019; 13:545. [PMID: 31866832 PMCID: PMC6908466 DOI: 10.3389/fncel.2019.00545] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2019] [Accepted: 11/22/2019] [Indexed: 01/01/2023] Open
Abstract
Human gastrointestinal (GI)-tract microbiome-derived lipopolysaccharide (LPS): (i) has been recently shown to target, accumulate within, and eventually encapsulate neuronal nuclei of the human central nervous system (CNS) in Alzheimer's disease (AD) brain; and (ii) this action appears to impede and restrict the outward flow of genetic information from neuronal nuclei. It has previously been shown that in LPS-encased neuronal nuclei in AD brain there is a specific disruption in the output and expression of two AD-relevant, neuron-specific markers encoding the cytoskeletal neurofilament light (NF-L) chain protein and the synaptic phosphoprotein synapsin-1 (SYN1) involved in the regulation of neurotransmitter release. The biophysical mechanisms involved in the facilitation of the targeting of LPS to neuronal cells and nuclei and eventual nuclear envelopment and functional disruption are not entirely clear. In this "Perspectives article" we discuss current advances, and consider future directions in this research area, and provide novel evidence in human neuronal-glial (HNG) cells in primary culture that the co-incubation of LPS with amyloid-beta 42 (Aβ42) peptide facilitates the association of LPS with neuronal cells. These findings: (i) support a novel pathogenic role for Aβ42 peptides in neurons via the formation of pores across the nuclear membrane and/or a significant biophysical disruption of the neuronal nuclear envelope; and (ii) advance the concept that the Aβ42 peptide-facilitated entry of LPS into brain neurons, accession of neuronal nuclei, and down-regulation of neuron-specific components such as NF-L and SYN1 may contribute significantly to neuropathological deficits as are characteristically observed in AD-affected brain.
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Affiliation(s)
- Walter J. Lukiw
- LSU Neuroscience Center, Louisiana State University Health Sciences Center, New Orleans, LA, United States
- Department of Ophthalmology, Louisiana State University Health Sciences Center, New Orleans, LA, United States
- Department of Neurology, Louisiana State University Health Sciences Center, New Orleans, LA, United States
| | - Wenhong Li
- LSU Neuroscience Center, Louisiana State University Health Sciences Center, New Orleans, LA, United States
- Department of Pharmacology, School of Pharmacy, Jiangxi University of Traditional Chinese Medicine (TCM), Nanchang, China
| | - Taylor Bond
- LSU Neuroscience Center, Louisiana State University Health Sciences Center, New Orleans, LA, United States
| | - Yuhai Zhao
- LSU Neuroscience Center, Louisiana State University Health Sciences Center, New Orleans, LA, United States
- Department of Anatomy and Cell Biology, Louisiana State University Health Sciences Center, New Orleans, LA, United States
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94
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Vander Zanden CM, Wampler L, Bowers I, Watkins EB, Majewski J, Chi EY. Fibrillar and Nonfibrillar Amyloid Beta Structures Drive Two Modes of Membrane-Mediated Toxicity. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2019; 35:16024-16036. [PMID: 31509701 PMCID: PMC7385729 DOI: 10.1021/acs.langmuir.9b02484] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
In Alzheimer's disease, the amyloid-beta peptide (Aβ) is implicated in neuronal toxicity via interactions with the cell membrane. Monomeric Aβ (Aβm) is intrinsically disordered, but it can adopt a range of aggregated conformations with varying toxicities from short fibrillar oligomers (FO), to globular nonfibrillar oligomers (NFO), and full-length amyloid fibrils. NFO is considered to be the most toxic, followed by fibrils, and finally Aβm. To elucidate molecular-level membrane interactions that contribute to their different toxicities, we used liquid surface X-ray scattering and Langmuir trough insertion assays to compare Aβm, FO, and NFO surface activities and interactions with anionic DMPG lipid monolayers at the air/water interface. All Aβ species were highly surface active and rapidly adopted β-sheet rich structures upon adsorption to the air/water interface. Likewise, all Aβ species had affinity for the anionic membrane. Aβm rapidly converted to β-sheet rich assemblies upon binding the membrane, and these aggregated structures of Aβm and FO disrupted hexagonally packed lipid domains and resulted in membrane thinning and instability. In contrast, NFO perturbed membrane structure by extracting lipids from the air/water interface and causing macroscale membrane deformations. Altogether, our results support two models for membrane-mediated Aβ toxicity: fibril-induced reorganization of lipid packing and NFO-induced membrane destabilization and lipid extraction. This work provides a structural understanding of Aβ neurotoxicity via membrane interactions and aids the effort in understanding early events in Alzheimer's disease and other neurodegenerative diseases.
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Affiliation(s)
- Crystal M Vander Zanden
- Center for Biomedical Engineering , University of New Mexico , Albuquerque , New Mexico 87131 , United States
- Department of Chemical and Biological Engineering , University of New Mexico , Albuquerque , New Mexico 87131 , United States
- Department of Chemistry and Biochemistry , University of Colorado Colorado Springs , Colorado Springs , Colorado 80918 , United States
| | - Lois Wampler
- Department of Biomedical Engineering , Texas A&M University , College Station , Texas 77843 , United States
| | - Isabella Bowers
- Department of Engineering and Technology , Southeast Missouri State University , Cape Girardeau , Missouri 63701 , United States
| | - Erik B Watkins
- MPA-11: Materials Synthesis and Integrated Devices , Los Alamos National Laboratory , Los Alamos , New Mexico 87545 , United States
| | - Jaroslaw Majewski
- Department of Chemical and Biological Engineering , University of New Mexico , Albuquerque , New Mexico 87131 , United States
- Division of Molecular and Cellular Biosciences , National Science Foundation , Alexandria , Virginia 22314 , United States
- Theoretical Biology and Biophysics , Los Alamos National Laboratory , Los Alamos , New Mexico 87545 , United States
| | - Eva Y Chi
- Center for Biomedical Engineering , University of New Mexico , Albuquerque , New Mexico 87131 , United States
- Department of Chemical and Biological Engineering , University of New Mexico , Albuquerque , New Mexico 87131 , United States
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95
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Hawk LML, Pittman JM, Moore PC, Srivastava AK, Zerweck J, Williams JTB, Hawk AJ, Sachleben JR, Meredith SC. β-amyloid model core peptides: Effects of hydrophobes and disulfides. Protein Sci 2019; 29:527-541. [PMID: 31710741 DOI: 10.1002/pro.3778] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2019] [Revised: 10/30/2019] [Accepted: 10/31/2019] [Indexed: 12/22/2022]
Abstract
The mechanism by which a disordered peptide nucleates and forms amyloid is incompletely understood. A central domain of β-amyloid (Aβ21-30) has been proposed to have intrinsic structural propensities that guide the limited formation of structure in the process of fibrillization. In order to test this hypothesis, we examine several internal fragments of Aβ, and variants of these either cyclized or with an N-terminal Cys. While Aβ21-30 and variants were always monomeric and unstructured (circular dichroism (CD) and nuclear magnetic resonance spectroscopy (NMRS)), we found that the addition of flanking hydrophobic residues in Aβ16-34 led to formation of typical amyloid fibrils. NMR showed no long-range nuclear overhauser effect (nOes) in Aβ21-30, Aβ16-34, or their variants, however. Serial 1 H-15 N-heteronuclear single quantum coherence spectroscopy, 1 H-1 H nuclear overhauser effect spectroscopy, and 1 H-1 H total correlational spectroscopy spectra were used to follow aggregation of Aβ16-34 and Cys-Aβ16-34 at a site-specific level. The addition of an N-terminal Cys residue (in Cys-Aβ16-34) increased the rate of fibrillization which was attributable to disulfide bond formation. We propose a scheme comparing the aggregation pathways for Aβ16-34 and Cys-Aβ16-34, according to which Cys-Aβ16-34 dimerizes, which accelerates fibril formation. In this context, cysteine residues form a focal point that guides fibrillization, a role which, in native peptides, can be assumed by heterogeneous nucleators of aggregation.
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Affiliation(s)
- Laura M L Hawk
- Department of Chemistry, The University of Chicago, Chicago, Illinois
| | - Jay M Pittman
- Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, Illinois
| | - Patrick C Moore
- Department of Pathology, The University of Chicago, Chicago, Illinois
| | - Atul K Srivastava
- Department of Pathology, The University of Chicago, Chicago, Illinois
| | - Jonathan Zerweck
- Department of Pathology, The University of Chicago, Chicago, Illinois
| | | | - Andrew J Hawk
- Department of Pathology, The University of Chicago, Chicago, Illinois
| | - Joseph R Sachleben
- Biomolecular NMR Core Facility, The University of Chicago, Chicago, Illinois
| | - Stephen C Meredith
- Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, Illinois.,Department of Pathology, The University of Chicago, Chicago, Illinois
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96
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Braidy N, Zarka M, Jugder BE, Welch J, Jayasena T, Chan DKY, Sachdev P, Bridge W. The Precursor to Glutathione (GSH), γ-Glutamylcysteine (GGC), Can Ameliorate Oxidative Damage and Neuroinflammation Induced by Aβ 40 Oligomers in Human Astrocytes. Front Aging Neurosci 2019; 11:177. [PMID: 31440155 PMCID: PMC6694290 DOI: 10.3389/fnagi.2019.00177] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2019] [Accepted: 07/02/2019] [Indexed: 12/12/2022] Open
Abstract
Glutathione (GSH) is one of the most abundant thiol antioxidants in cells. Many chronic and age-related diseases are associated with a decline in cellular GSH levels or impairment in the catalytic activity of the GSH biosynthetic enzyme glutamate cysteine ligase (GCL). γ-glutamylcysteine (GGC), a precursor to glutathione (GSH), can replenish depleted GSH levels under oxidative stress conditions, by circumventing the regulation of GSH biosynthesis and providing the limiting substrate. Soluble amyloid-β (Aβ) oligomers have been shown to induce oxidative stress, synaptic dysfunction and memory deficits which have been reported in Alzheimer’s disease (AD). Calcium ions, which are increased with age and in AD, have been previously reported to enhance the formation of Aβ40 oligomers, which have been casually associated with the pathogenesis of the underlying neurodegenerative condition. In this study, we examined the potential beneficial effects of GGC against exogenous Aβ40 oligomers on biomarkers of apoptosis and cell death, oxidative stress, and neuroinflammation, in human astrocytes. Treatment with Aβ40 oligomers significantly reduced the cell viability and apoptosis of astrocyte brain cultures and increased oxidative modifications of DNA, lipids, and protein, enhanced pro-inflammatory cytokine release and increased the activity of the proteolytic matrix metalloproteinase enzyme, matric metalloproteinase (MMP)-2 and reduced the activity of MMP-9 after 24 h. Co-treatment of Aβ40 oligomers with GGC at 200 μM increased the activity of the antioxidant enzymes superoxide dismutase (SOD) and glutathione peroxidase (GPx) and led to significant increases in the levels of the total antioxidant capacity (TAC) and GSH and reduced the GSSG/GSH ratio. GGC also upregulated the level of the anti-inflammatory cytokine IL-10 and reduced the levels of the pro-inflammatory cytokines (TNF-α, IL-6, and IL-1β) and attenuated the changes in metalloproteinase activity in oligomeric Aβ40-treated astrocytes. Our data provides renewed insight on the beneficial effects of increased GSH levels by GGC in human astrocytes, and identifies yet another potential therapeutic strategy to attenuate the cytotoxic effects of Aβ oligomers in AD.
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Affiliation(s)
- Nady Braidy
- Centre for Healthy Ageing, School of Psychiatry, Faculty of Medicine, University of New South Wales, Sydney, NSW, Australia
| | - Martin Zarka
- School of Biotechnology and Biomolecular Sciences, Faculty of Science, University of New South Wales, Sydney, NSW, Australia
| | - Bat-Erdene Jugder
- School of Biotechnology and Biomolecular Sciences, Faculty of Science, University of New South Wales, Sydney, NSW, Australia
| | - Jeffrey Welch
- School of Biotechnology and Biomolecular Sciences, Faculty of Science, University of New South Wales, Sydney, NSW, Australia
| | - Tharusha Jayasena
- Centre for Healthy Ageing, School of Psychiatry, Faculty of Medicine, University of New South Wales, Sydney, NSW, Australia
| | - Daniel K Y Chan
- Faculty of Medicine, University of New South Wales, Sydney, NSW, Australia.,Department of Aged Care and Rehabilitation, Bankstown Hospital, Bankstown, NSW, Australia
| | - Perminder Sachdev
- Neuropsychiatric Institute, Euroa Centre, Prince of Wales Hospital, Sydney, NSW, Australia
| | - Wallace Bridge
- School of Biotechnology and Biomolecular Sciences, Faculty of Science, University of New South Wales, Sydney, NSW, Australia
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97
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Modulation of Innate Immunity by Amyloidogenic Peptides. Trends Immunol 2019; 40:762-780. [PMID: 31320280 DOI: 10.1016/j.it.2019.06.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2019] [Revised: 06/11/2019] [Accepted: 06/12/2019] [Indexed: 12/11/2022]
Abstract
Amyloid formation contributes to the development of progressive metabolic and neurodegenerative diseases, while also serving functional roles in host defense. Emerging evidence suggests that as amyloidogenic peptides populate distinct aggregation states, they interact with different combinations of pattern recognition receptors (PRRs) to direct the phenotype and function of tissue-resident and infiltrating innate immune cells. We review recent evidence of innate immunomodulation by distinct forms of amyloidogenic peptides produced by mammals (humans, non-human primates), bacteria, and fungi, as well as the corresponding cell-surface and intracellular PRRs in these interactions, in human and mouse models. Our emerging understanding of peptide aggregate-innate immune cell interactions, and the factors regulating the balance between amyloid function and pathogenicity, might aid the development of anti-amyloid and immunomodulating therapies.
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98
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Banerjee S, Lyubchenko YL. Interaction of Amyloidogenic Proteins with Membranes and Molecular Mechanism for the Development of Alzheimer's disease. ALZHEIMER'S RESEARCH & THERAPY OPEN ACCESS 2019; 2:106. [PMID: 33135011 PMCID: PMC7597641] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Molecular mechanism of diseases like Alzheimer's disease (AD) and Parkinson's diseases (PD) is associated with misfolding of specific proteins, such as amyloid beta (Aβ) proteins in the case of AD, followed by their self-assembly into toxic oligomers along with the formation of amyloid fibrils assembled as plaques in the brain. Interaction of Aβ with membrane can lead to membrane damage; this process is considered as the major factor associated with the AD development. Additionally, membrane can facilitate the aggregation process of Aβ proteins. This important property of membranes is discussed in this review. A specific emphasis is given to the recently discovered property of cellular membranes to catalyze the initial step of Aβ aggregation process by which self-assembly of Aβ can be observed at physiologically low concentrations of Aβ proteins. At such low concentrations, no spontaneous aggregation occurs in the bulk solution. This fact was a major weakness of the protein aggregation model for AD. The catalytic property of membrane surfaces towards Aβ aggregation depends on the membrane composition. This finding suggests a number of novel ideas on the development of treatments and preventions for AD, which is briefly discussed in the review.
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Affiliation(s)
| | - YL Lyubchenko
- Corresponding author: Yuri L Lyubchenko Department of Pharmaceutical Sciences, University of Nebraska Medical Center, 986025 Nebraska Medical Center, Omaha, NE 68198-6025, USA, Tel: 1-402-559-1971;
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99
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Protein misfolding, aggregation and mechanism of amyloid cytotoxicity: An overview and therapeutic strategies to inhibit aggregation. Int J Biol Macromol 2019; 134:1022-1037. [PMID: 31128177 DOI: 10.1016/j.ijbiomac.2019.05.109] [Citation(s) in RCA: 67] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2019] [Revised: 05/18/2019] [Accepted: 05/18/2019] [Indexed: 12/18/2022]
Abstract
Protein and peptides are converted from their soluble forms into highly ordered fibrillar aggregates under various conditions inside the cell. Such transitions confer diverse neurodegenerative diseases including Alzheimer's disease, Huntington's disease Prion's disease, Parkinson's disease, polyQ and share abnormal folding of potentially cytotoxic protein species linked with degeneration and death of precise neuronal populations. Presently, major advances are made to understand and get detailed insight into the structural basis and mechanism of amyloid formation, cytotoxicity and therapeutic approaches to combat them. Here we highlight classifies and summarizes the detailed overview of protein misfolding and aggregation at their molecular level including the factors that promote protein aggregation under in vivo and in vitro conditions. In addition, we describe the recent technologies that aid the characterization of amyloid aggregates along with several models that might be responsible for amyloid induced cytotoxicity to cells. Overview on the inhibition of amyloidosis by targeting different small molecules (both natural and synthetic origin) have been also discussed, that provides important approaches to identify novel targets and develop specific therapeutic strategies to combat protein aggregation related neurodegenerative diseases.
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