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Żukowska J, Moss SJ, Subramanian V, Acharya KR. Molecular basis of selective amyloid-β degrading enzymes in Alzheimer's disease. FEBS J 2024; 291:2999-3029. [PMID: 37622248 DOI: 10.1111/febs.16939] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2023] [Revised: 07/31/2023] [Accepted: 08/22/2023] [Indexed: 08/26/2023]
Abstract
The accumulation of the small 42-residue long peptide amyloid-β (Aβ) has been proposed as a major trigger for the development of Alzheimer's disease (AD). Within the brain, the concentration of Aβ peptide is tightly controlled through production and clearance mechanisms. Substantial experimental evidence now shows that reduced levels of Aβ clearance are present in individuals living with AD. This accumulation of Aβ can lead to the formation of large aggregated amyloid plaques-one of two detectable hallmarks of the disease. Aβ-degrading enzymes (ADEs) are major players in the clearance of Aβ. Stimulating ADE activity or expression, in order to compensate for the decreased clearance in the AD phenotype, provides a promising therapeutic target. It has been reported in mice that upregulation of ADEs can reduce the levels of Aβ peptide and amyloid plaques-in some cases, this led to improved cognitive function. Among several known ADEs, neprilysin (NEP), endothelin-converting enzyme-1 (ECE-1), insulin degrading enzyme (IDE) and angiotensin-1 converting enzyme (ACE) from the zinc metalloprotease family have been identified as important. These ADEs have the capacity to digest soluble Aβ which, in turn, cannot form the toxic oligomeric species. While they are known for their amyloid degradation, they exhibit complexity through promiscuous nature and a broad range of substrates that they can degrade. This review highlights current structural and functional understanding of these key ADEs, giving some insight into the molecular interactions that leads to the hydrolysis of peptide substrates, the crucial tasks performed by them and the potential for therapeutic use in the future.
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2
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de Athayde Moncorvo Collado A, Socías SB, González-Lizárraga F, Ploper D, Vera Pingitore E, Chehín RN, Chaves S. Magnetic amyloid-based biocatalyst for the hydrolysis of urea. Food Chem 2024; 433:136830. [PMID: 37683486 DOI: 10.1016/j.foodchem.2023.136830] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2023] [Revised: 06/19/2023] [Accepted: 07/05/2023] [Indexed: 09/10/2023]
Abstract
The presence of urea in wines and other alcoholic beverages represents a critical problem since it can chemically react with ethanol, which leads to the formation of ethyl carbamate, a carcinogenic agent according to the World Health Organization. Here we report the creation of a biocatalyst for the hydrolysis of urea, which could potentially be used before bottling alcoholic drinks. For this, the effective surface area of streptavidin-labeled magnetic microparticles was amplified by functionalization with biotin-labeled hen egg lysozyme amyloid fibers. Subsequently, by using copper and hydrogen peroxide induced cross-linking of unmodified proteins (CHICUP), soybean urease was immobilized to the fibers. This gave rise to a magnetic biocatalyst with remarkable urease activity, which was maintained even after 10 reuses. We propose that this strategy could be used as a platform for immobilizing other molecules to design and develop a myriad of biocatalysts for the food industry.
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Affiliation(s)
- A de Athayde Moncorvo Collado
- Instituto de Medicina Molecular y Celular Aplicada, Universidad Nacional de Tucumán-Consejo Nacional de Investigación Científicas y Técnicas- Sistema Provincial de Salud (UNT-CONICET-SIPROSA), Pasaje Manuel Dorrego, 1080. CP 4000. Tucumán, Argentina; Instituto Superior de Investigaciones Biológicas (INSIBIO, CONICET-UNT). Instituto de Química Biológica "Dr. Bernabé Bloj", Facultad de Bioquímica, Química y Farmacia, UNT, Batalla de Chacabuco 461, CP 4000 Tucumán, Argentina.
| | - S B Socías
- Instituto de Medicina Molecular y Celular Aplicada, Universidad Nacional de Tucumán-Consejo Nacional de Investigación Científicas y Técnicas- Sistema Provincial de Salud (UNT-CONICET-SIPROSA), Pasaje Manuel Dorrego, 1080. CP 4000. Tucumán, Argentina.
| | - F González-Lizárraga
- Instituto de Medicina Molecular y Celular Aplicada, Universidad Nacional de Tucumán-Consejo Nacional de Investigación Científicas y Técnicas- Sistema Provincial de Salud (UNT-CONICET-SIPROSA), Pasaje Manuel Dorrego, 1080. CP 4000. Tucumán, Argentina.
| | - D Ploper
- Instituto de Medicina Molecular y Celular Aplicada, Universidad Nacional de Tucumán-Consejo Nacional de Investigación Científicas y Técnicas- Sistema Provincial de Salud (UNT-CONICET-SIPROSA), Pasaje Manuel Dorrego, 1080. CP 4000. Tucumán, Argentina.
| | - E Vera Pingitore
- Instituto de Medicina Molecular y Celular Aplicada, Universidad Nacional de Tucumán-Consejo Nacional de Investigación Científicas y Técnicas- Sistema Provincial de Salud (UNT-CONICET-SIPROSA), Pasaje Manuel Dorrego, 1080. CP 4000. Tucumán, Argentina.
| | - R N Chehín
- Instituto de Medicina Molecular y Celular Aplicada, Universidad Nacional de Tucumán-Consejo Nacional de Investigación Científicas y Técnicas- Sistema Provincial de Salud (UNT-CONICET-SIPROSA), Pasaje Manuel Dorrego, 1080. CP 4000. Tucumán, Argentina; Instituto Superior de Investigaciones Biológicas (INSIBIO, CONICET-UNT). Instituto de Química Biológica "Dr. Bernabé Bloj", Facultad de Bioquímica, Química y Farmacia, UNT, Batalla de Chacabuco 461, CP 4000 Tucumán, Argentina.
| | - S Chaves
- Instituto de Medicina Molecular y Celular Aplicada, Universidad Nacional de Tucumán-Consejo Nacional de Investigación Científicas y Técnicas- Sistema Provincial de Salud (UNT-CONICET-SIPROSA), Pasaje Manuel Dorrego, 1080. CP 4000. Tucumán, Argentina.
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3
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Han J. Copper trafficking systems in cells: insights into coordination chemistry and toxicity. Dalton Trans 2023; 52:15277-15296. [PMID: 37702384 DOI: 10.1039/d3dt02166a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/14/2023]
Abstract
Transition metal ions, such as copper, are indispensable components in the biological system. Copper ions which primarily exist in two major oxidation states Cu(I) and Cu(II) play crucial roles in various cellular processes including antioxidant defense, biosynthesis of neurotransmitters, and energy metabolism, owing to their inherent redox activity. The disturbance in copper homeostasis can contribute to the development of copper metabolism disorders, cancer, and neurodegenerative diseases, highlighting the significance of understanding the copper trafficking system in cellular environments. This review aims to offer a comprehensive overview of copper homeostatic machinery, with an emphasis on the coordination chemistry of copper transporters and trafficking proteins. While copper chaperones and the corresponding metalloenzymes are thoroughly discussed, we also explore the potential existence of low-molecular-mass metal complexes within cellular systems. Furthermore, we summarize the toxicity mechanisms originating from copper deficiency or accumulation, which include the dysregulation of oxidative stress, signaling pathways, signal transduction, and amyloidosis. This perspective review delves into the current knowledge regarding the intricate aspects of the copper trafficking system, providing valuable insights into potential treatment strategies from the standpoint of bioinorganic chemistry.
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Affiliation(s)
- Jiyeon Han
- Department of Applied Chemistry, University of Seoul, Seoul 02504, Republic of Korea.
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4
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Zhang YY, Ren KD, Luo XJ, Peng J. COVID-19-induced neurological symptoms: focus on the role of metal ions. Inflammopharmacology 2023; 31:611-631. [PMID: 36892679 PMCID: PMC9996599 DOI: 10.1007/s10787-023-01176-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2023] [Accepted: 02/23/2023] [Indexed: 03/10/2023]
Abstract
Neurological symptoms are prevalent in both the acute and post-acute phases of coronavirus disease 2019 (COVID-19), and they are becoming a major concern for the prognosis of COVID-19 patients. Accumulation evidence has suggested that metal ion disorders occur in the central nervous system (CNS) of COVID-19 patients. Metal ions participate in the development, metabolism, redox and neurotransmitter transmission in the CNS and are tightly regulated by metal ion channels. COVID-19 infection causes neurological metal disorders and metal ion channels abnormal switching, subsequently resulting in neuroinflammation, oxidative stress, excitotoxicity, neuronal cell death, and eventually eliciting a series of COVID-19-induced neurological symptoms. Therefore, metal homeostasis-related signaling pathways are emerging as promising therapeutic targets for mitigating COVID-19-induced neurological symptoms. This review provides a summary for the latest advances in research related to the physiological and pathophysiological functions of metal ions and metal ion channels, as well as their role in COVID-19-induced neurological symptoms. In addition, currently available modulators of metal ions and their channels are also discussed. Collectively, the current work offers a few recommendations according to published reports and in-depth reflections to ameliorate COVID-19-induced neurological symptoms. Further studies need to focus on the crosstalk and interactions between different metal ions and their channels. Simultaneous pharmacological intervention of two or more metal signaling pathway disorders may provide clinical advantages in treating COVID-19-induced neurological symptoms.
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Affiliation(s)
- Yi-Yue Zhang
- Department of Pharmacology, Xiangya School of Pharmaceutical Sciences, Central South University, Changsha, 410078, China.,Department of Laboratory Medicine, The Third Xiangya Hospital of Central South University, Changsha, 410013, China
| | - Kai-Di Ren
- Department of Pharmacy, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, 450052, China
| | - Xiu-Ju Luo
- Department of Laboratory Medicine, The Third Xiangya Hospital of Central South University, Changsha, 410013, China.
| | - Jun Peng
- Department of Pharmacology, Xiangya School of Pharmaceutical Sciences, Central South University, Changsha, 410078, China. .,Hunan Provincial Key Laboratory of Cardiovascular Research, Xiangya School of Pharmaceutical Sciences, Central South University, Changsha, 410078, China.
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5
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Ghosh S, Ali R, Verma S. Aβ-oligomers: A potential therapeutic target for Alzheimer's disease. Int J Biol Macromol 2023; 239:124231. [PMID: 36996958 DOI: 10.1016/j.ijbiomac.2023.124231] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Revised: 03/22/2023] [Accepted: 03/25/2023] [Indexed: 03/30/2023]
Abstract
The cascade of amyloid formation relates to multiple complex events at the molecular level. Previous research has established amyloid plaque deposition as the leading cause of Alzheimer's disease (AD) pathogenesis, detected mainly in aged population. The primary components of the plaques are two alloforms of amyloid-beta (Aβ), Aβ1-42 and Aβ1-40 peptides. Recent studies have provided considerable evidence contrary to the previous claim indicating that amyloid-beta oligomers (AβOs) as the main culprit responsible for AD-associated neurotoxicity and pathogenesis. In this review, we have discussed the primary features of AβOs, such as assembly formation, the kinetics of oligomer formation, interactions with various membranes/membrane receptors, the origin of toxicity, and oligomer-specific detection methods. Recently, the discovery of rationally designed antibodies has opened a gateway for using synthesized peptides as a grafting component in the complementarity determining region (CDR) of antibodies. Thus, the Aβ sequence motif or the complementary peptide sequence in the opposite strand of the β-sheet (extracted from the Protein Data Bank: PDB) helps design oligomer-specific inhibitors. The microscopic event responsible for oligomer formation can be targeted, and thus prevention of the overall macroscopic behaviour of the aggregation or the associated toxicity can be achieved. We have carefully reviewed the oligomer formation kinetics and associated parameters. Besides, we have depicted a thorough understanding of how the synthesized peptide inhibitors can impede the early aggregates (oligomers), mature fibrils, monomers, or a mixture of the species. The oligomer-specific inhibitors (peptides or peptide fragments) lack in-depth chemical kinetics and optimization control-based screening. In the present review, we have proposed a hypothesis for effectively screening oligomer-specific inhibitors using the chemical kinetics (determining the kinetic parameters) and optimization control strategy (cost-dependent analysis). Further, it may be possible to implement the structure-kinetic-activity-relationship (SKAR) strategy instead of structure-activity-relationship (SAR) to improve the inhibitor's activity. The controlled optimization of the kinetic parameters and dose usage will be beneficial for narrowing the search window for the inhibitors.
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Berntsson E, Vosough F, Svantesson T, Pansieri J, Iashchishyn IA, Ostojić L, Dong X, Paul S, Jarvet J, Roos PM, Barth A, Morozova-Roche LA, Gräslund A, Wärmländer SKTS. Residue-specific binding of Ni(II) ions influences the structure and aggregation of amyloid beta (Aβ) peptides. Sci Rep 2023; 13:3341. [PMID: 36849796 PMCID: PMC9971182 DOI: 10.1038/s41598-023-29901-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2022] [Accepted: 02/13/2023] [Indexed: 03/01/2023] Open
Abstract
Alzheimer's disease (AD) is the most common cause of dementia worldwide. AD brains display deposits of insoluble amyloid plaques consisting mainly of aggregated amyloid-β (Aβ) peptides, and Aβ oligomers are likely a toxic species in AD pathology. AD patients display altered metal homeostasis, and AD plaques show elevated concentrations of metals such as Cu, Fe, and Zn. Yet, the metal chemistry in AD pathology remains unclear. Ni(II) ions are known to interact with Aβ peptides, but the nature and effects of such interactions are unknown. Here, we use numerous biophysical methods-mainly spectroscopy and imaging techniques-to characterize Aβ/Ni(II) interactions in vitro, for different Aβ variants: Aβ(1-40), Aβ(1-40)(H6A, H13A, H14A), Aβ(4-40), and Aβ(1-42). We show for the first time that Ni(II) ions display specific binding to the N-terminal segment of full-length Aβ monomers. Equimolar amounts of Ni(II) ions retard Aβ aggregation and direct it towards non-structured aggregates. The His6, His13, and His14 residues are implicated as binding ligands, and the Ni(II)·Aβ binding affinity is in the low µM range. The redox-active Ni(II) ions induce formation of dityrosine cross-links via redox chemistry, thereby creating covalent Aβ dimers. In aqueous buffer Ni(II) ions promote formation of beta sheet structure in Aβ monomers, while in a membrane-mimicking environment (SDS micelles) coil-coil helix interactions appear to be induced. For SDS-stabilized Aβ oligomers, Ni(II) ions direct the oligomers towards larger sizes and more diverse (heterogeneous) populations. All of these structural rearrangements may be relevant for the Aβ aggregation processes that are involved in AD brain pathology.
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Affiliation(s)
- Elina Berntsson
- Department of Biochemistry and Biophysics, Arrhenius Laboratories, Stockholm University, 106 91, Stockholm, Sweden. .,Department of Chemistry and Biotechnology, Tallinn University of Technology, Tallinn, Estonia.
| | - Faraz Vosough
- grid.10548.380000 0004 1936 9377Department of Biochemistry and Biophysics, Arrhenius Laboratories, Stockholm University, 106 91 Stockholm, Sweden
| | - Teodor Svantesson
- grid.10548.380000 0004 1936 9377Department of Biochemistry and Biophysics, Arrhenius Laboratories, Stockholm University, 106 91 Stockholm, Sweden
| | - Jonathan Pansieri
- grid.12650.300000 0001 1034 3451Department of Medical Biochemistry and Biophysics, Umeå University, 901 87 Umeå, Sweden
| | - Igor A. Iashchishyn
- grid.12650.300000 0001 1034 3451Department of Medical Biochemistry and Biophysics, Umeå University, 901 87 Umeå, Sweden
| | - Lucija Ostojić
- grid.12650.300000 0001 1034 3451Department of Medical Biochemistry and Biophysics, Umeå University, 901 87 Umeå, Sweden
| | - Xiaolin Dong
- grid.10548.380000 0004 1936 9377Department of Biochemistry and Biophysics, Arrhenius Laboratories, Stockholm University, 106 91 Stockholm, Sweden
| | - Suman Paul
- grid.10548.380000 0004 1936 9377Department of Biochemistry and Biophysics, Arrhenius Laboratories, Stockholm University, 106 91 Stockholm, Sweden
| | - Jüri Jarvet
- grid.10548.380000 0004 1936 9377Department of Biochemistry and Biophysics, Arrhenius Laboratories, Stockholm University, 106 91 Stockholm, Sweden ,grid.177284.f0000 0004 0410 6208The National Institute of Chemical Physics and Biophysics, Tallinn, Estonia
| | - Per M. Roos
- grid.4714.60000 0004 1937 0626Institute of Environmental Medicine, Karolinska Institutet, Nobels Väg 13, 171 77 Stockholm, Sweden ,Department of Clinical Physiology, Capio St. Göran Hospital, St. Göransplan 1, 112 19 Stockholm, Sweden
| | - Andreas Barth
- grid.10548.380000 0004 1936 9377Department of Biochemistry and Biophysics, Arrhenius Laboratories, Stockholm University, 106 91 Stockholm, Sweden
| | - Ludmilla A. Morozova-Roche
- grid.12650.300000 0001 1034 3451Department of Medical Biochemistry and Biophysics, Umeå University, 901 87 Umeå, Sweden
| | - Astrid Gräslund
- grid.10548.380000 0004 1936 9377Department of Biochemistry and Biophysics, Arrhenius Laboratories, Stockholm University, 106 91 Stockholm, Sweden
| | - Sebastian K. T. S. Wärmländer
- grid.10548.380000 0004 1936 9377Chemistry Section, Arrhenius Laboratories, Stockholm University, 106 91, Stockholm, Sweden
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Andrews B, Ruggiero T, Urbanc B. How do salt and lipids affect conformational dynamics of Aβ42 monomers in water? Phys Chem Chem Phys 2023; 25:2566-2583. [PMID: 36602150 DOI: 10.1039/d2cp05044g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
It is well established that amyloid β-protein (Aβ) self-assembly is involved in triggering of Alzheimer's disease. On the other hand, evidence of physiological function of Aβ interacting with lipids has only begun to emerge. Details of Aβ-lipid interactions, which may underlie physiological and pathological activities of Aβ, are not well understood. Here, the effects of salt and 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) lipids on conformational dynamics of Aβ42 monomer in water are examined by all-atom molecular dynamics (MD). We acquired six sets of 250 ns long MD trajectories for each of the three lipid concentrations (0, 27, and 109 mM) in the absence and presence of 150 mM salt. Ten replica trajectories per set are used to enhance sampling of Aβ42 conformational space. We show that salt facilitates long-range tertiary contacts in Aβ42, resulting in more compact Aβ42 conformations. By contrast, addition of lipids results in lipid-concentration dependent Aβ42 unfolding concomitant with enhanced stability of the turn in the A21-A30 region. At the high lipid concentration, salt enables the N-terminal region of Aβ42 to form long-range tertiary contacts and interact with lipids, which results in formation of a parallel β-strand. Aβ42 forms stable lipid-protein complexes whereby the protein is adhered to the lipid cluster rather than embedded into it. We propose that the inability of Aβ42 monomer to get embedded into the lipid cluster may be important for facilitating repair of leaks in the blood-brain barrier without penetrating and damaging cellular membranes.
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Affiliation(s)
- Brian Andrews
- Department of Physics, Drexel University, Philadelphia, Pennsylvania, USA.
| | - Thomas Ruggiero
- Department of Physics, Drexel University, Philadelphia, Pennsylvania, USA.
| | - Brigita Urbanc
- Department of Physics, Drexel University, Philadelphia, Pennsylvania, USA.
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8
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Maina MB, Al-Hilaly YK, Serpell LC. Dityrosine cross-linking and its potential roles in Alzheimer's disease. Front Neurosci 2023; 17:1132670. [PMID: 37034163 PMCID: PMC10075315 DOI: 10.3389/fnins.2023.1132670] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2022] [Accepted: 03/01/2023] [Indexed: 04/11/2023] Open
Abstract
Oxidative stress is a significant source of damage that accumulates during aging and contributes to Alzheimer's disease (AD) pathogenesis. Oxidation of proteins can give rise to covalent links between adjacent tyrosines known as dityrosine (DiY) cross-linking, amongst other modifications, and this observation suggests that DiY could serve as a biomarker of accumulated oxidative stress over the lifespan. Many studies have focused on understanding the contribution of DiY to AD pathogenesis and have revealed that DiY crosslinks can be found in both Aβ and tau deposits - the two key proteins involved in the formation of amyloid plaques and tau tangles, respectively. However, there is no consensus yet in the field on the impact of DiY on Aβ and tau function, aggregation, and toxicity. Here we review the current understanding of the role of DiY on Aβ and tau gathered over the last 20 years since the first observation, and discuss the effect of this modification for Aβ and tau aggregation, and its potential as a biomarker for AD.
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Affiliation(s)
- Mahmoud B. Maina
- Sussex Neuroscience, School of Life Sciences, University of Sussex, Falmer, United Kingdom
- Biomedical Science Research and Training Centre, College of Medical Sciences, Yobe State University, Damaturu, Nigeria
| | - Youssra K. Al-Hilaly
- Sussex Neuroscience, School of Life Sciences, University of Sussex, Falmer, United Kingdom
- Department of Chemistry, College of Science, Mustansiriyah University, Baghdad, Iraq
| | - Louise C. Serpell
- Sussex Neuroscience, School of Life Sciences, University of Sussex, Falmer, United Kingdom
- *Correspondence: Louise C. Serpell,
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Saha J, Bose P, Dhakal S, Ghosh P, Rangachari V. Ganglioside-Enriched Phospholipid Vesicles Induce Cooperative Aβ Oligomerization and Membrane Disruption. Biochemistry 2022; 61:2206-2220. [PMID: 36173882 PMCID: PMC9840156 DOI: 10.1021/acs.biochem.2c00495] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
A major hallmark of Alzheimer's disease (AD) is the accumulation of extracellular aggregates of amyloid-β (Aβ). Structural polymorphism observed among Aβ fibrils in AD brains seem to correlate with the clinical subtypes suggesting a link between fibril polymorphism and pathology. Since fibrils emerge from a templated growth of low-molecular-weight oligomers, understanding the factors affecting oligomer generation is important. Membrane lipids are key factors to influence early stages of Aβ aggregation and oligomer generation, which cause membrane disruption. We have previously demonstrated that conformationally discrete Aβ oligomers can be generated by modulating the charge, composition, and chain length of lipids and surfactants. Here, we extend our studies into liposomal models by investigating Aβ oligomerization on large unilamellar vesicles (LUVs) of total brain extracts (TBE), reconstituted lipid rafts (LRs), or 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC). Varying the vesicle composition by specifically increasing the amount of GM1 gangliosides as a constituent, we found that only GM1-enriched liposomes induce the formation of toxic, low-molecular-weight oligomers. Furthermore, we found that the aggregation on liposome surface and membrane disruption are highly cooperative and sensitive to membrane surface characteristics. Numerical simulations confirm such a cooperativity and reveal that GM1-enriched liposomes form twice as many pores as those formed in the absence GM1. Overall, this study uncovers mechanisms of cooperativity between oligomerization and membrane disruption under controlled lipid compositional bias, and refocuses the significance of the early stages of Aβ aggregation in polymorphism, propagation, and toxicity in AD.
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Affiliation(s)
- Jhinuk Saha
- Department of Chemistry and Biochemistry, School of Mathematics and Natural Sciences, University of Southern Mississippi, Hattiesburg, Mississippi 39406, United States
| | - Priyankar Bose
- Department of Computer Science, Virginia Commonwealth University, Richmond, Virginia 23220, United States
| | - Shailendra Dhakal
- Center for Molecular and Cellular Biosciences, University of Southern Mississippi, Hattiesburg, Mississippi 39406, United States
| | - Preetam Ghosh
- Department of Computer Science, Virginia Commonwealth University, Richmond, Virginia 23220, United States
| | - Vijayaraghavan Rangachari
- Department of Chemistry and Biochemistry, School of Mathematics and Natural Sciences, University of Southern Mississippi, Hattiesburg, Mississippi 39406, United States; Center for Molecular and Cellular Biosciences, University of Southern Mississippi, Hattiesburg, Mississippi 39406, United States
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10
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Gelation Methods to Assemble Fibrous Proteins. Methods Mol Biol 2022; 2347:149-165. [PMID: 34472063 DOI: 10.1007/978-1-0716-1574-4_14] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Gelation is an efficient way to fabricate fibrous protein materials. Briefly, it is an aggregation process where protein molecules assembly from a random structure into an organized structure such as nanofibrillar networks. According to their mechanisms, the fibrous proteins gelation can be classified into physical gelation and chemical gelation. The physical gelation is formed by the conformational transformation of fibroin proteins, which can be triggered by temperature, concentration, pH, or shear force. On the other hand, the chemical gelation is to cross-link fibrous proteins through chemical and/or enzymatic reactions. In this chapter, we summarize the protocols for preparing fibrous protein hydrogels, including both physical and chemical methods. The mechanisms of these gelation methods are also highlighted.
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11
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Kageyama Y, Irie Y, Matsushima Y, Segawa T, Bellier JP, Hidaka K, Sugiyama H, Kaneda D, Hashizume Y, Akatsu H, Miki K, Kita A, Walker DG, Irie K, Tooyama I. Characterization of a Conformation-Restricted Amyloid β Peptide and Immunoreactivity of Its Antibody in Human AD brain. ACS Chem Neurosci 2021; 12:3418-3432. [PMID: 34464082 DOI: 10.1021/acschemneuro.1c00416] [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: 12/26/2022] Open
Abstract
Characterization of amyloid β (Aβ) oligomers, the transition species present prior to the formation of Aβ fibrils and that have cytotoxicity, has become one of the major topics in the investigations of Alzheimer's disease (AD) pathogenesis. However, studying pathophysiological properties of Aβ oligomers is challenging due to the instability of these protein complexes in vitro. Here, we report that conformation-restricted Aβ42 with an intramolecular disulfide bond at positions 17 and 28 (SS-Aβ42) formed stable Aβ oligomers in vitro. Thioflavin T binding assays, nondenaturing gel electrophoresis, and morphological analyses revealed that SS-Aβ42 maintained oligomeric structure, whereas wild-type Aβ42 and the highly aggregative Aβ42 mutant with E22P substitution (E22P-Aβ42) formed Aβ fibrils. In agreement with these observations, SS-Aβ42 was more cytotoxic compared to the wild-type and E22P-Aβ42 in cell cultures. Furthermore, we developed a monoclonal antibody, designated TxCo-1, using the toxic conformation of SS-Aβ42 as immunogen. X-ray crystallography of the TxCo-1/SS-Aβ42 complex, enzyme immunoassay, and immunohistochemical studies confirmed the recognition site and specificity of TxCo-1 to SS-Aβ42. Immunohistochemistry with TxCo-1 antibody identified structures resembling senile plaques and vascular Aβ in brain samples of AD subjects. However, TxCo-1 immunoreactivity did not colocalize extensively with Aβ plaques identified with conventional Aβ antibodies. Together, these findings indicate that Aβ with a turn at positions 22 and 23, which is prone to form Aβ oligomers, could show strong cytotoxicity and accumulated in brains of AD subjects. The SS-Aβ42 and TxCo-1 antibody should facilitate understanding of the pathological role of Aβ with toxic conformation in AD.
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Affiliation(s)
- Yusuke Kageyama
- Molecular Neuroscience Research Center, Shiga University of Medical Science, Shiga 520-2192, Japan
| | - Yumi Irie
- Division of Food Science & Biotechnology, Graduate School of Agriculture, Kyoto University, Kyoto 606-8502, Japan
| | - Yuka Matsushima
- Division of Food Science & Biotechnology, Graduate School of Agriculture, Kyoto University, Kyoto 606-8502, Japan
| | - Tatsuya Segawa
- Immuno-Biological Laboratories Co., Ltd., Fujioka-Shi, Gunma 375-0005, Japan
| | - Jean-Pierre Bellier
- Molecular Neuroscience Research Center, Shiga University of Medical Science, Shiga 520-2192, Japan
| | - Kumi Hidaka
- Department of Chemistry, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
| | - Hiroshi Sugiyama
- Department of Chemistry, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
| | - Daita Kaneda
- Choju Medical Institute, Fukushimura Hospital, 19-14 Noyoricho, Yamanaka, Aichi 441-8124, Japan
| | - Yoshio Hashizume
- Choju Medical Institute, Fukushimura Hospital, 19-14 Noyoricho, Yamanaka, Aichi 441-8124, Japan
| | - Hiroyasu Akatsu
- Choju Medical Institute, Fukushimura Hospital, 19-14 Noyoricho, Yamanaka, Aichi 441-8124, Japan
- Department of Community-Based Medical Education, Nagoya City University Graduate School of Medicine, Nagoya, Aichi 467-8601, Japan
| | - Kunio Miki
- Department of Chemistry, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
| | - Akiko Kita
- Institute for Integrated Radiation and Nuclear Science, Kyoto University, Kumatori, Sennan, Osaka 590-0494, Japan
| | - Douglas G. Walker
- Molecular Neuroscience Research Center, Shiga University of Medical Science, Shiga 520-2192, Japan
| | - Kazuhiro Irie
- Division of Food Science & Biotechnology, Graduate School of Agriculture, Kyoto University, Kyoto 606-8502, Japan
| | - Ikuo Tooyama
- Molecular Neuroscience Research Center, Shiga University of Medical Science, Shiga 520-2192, Japan
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12
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Andrews B, Long K, Urbanc B. Soluble State of Villin Headpiece Protein as a Tool in the Assessment of MD Force Fields. J Phys Chem B 2021; 125:6897-6911. [PMID: 34143637 DOI: 10.1021/acs.jpcb.1c04589] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Protein self-assembly plays an important role in cellular processes. Whereas molecular dynamics (MD) represents a powerful tool in studying assembly mechanisms, its predictions depend on the accuracy of underlying force fields, which are known to overly promote protein assembly. We here examine villin headpiece domain, HP36, which remains soluble at concentrations amenable to MD studies. The experimental characterization of soluble HP36 at concentrations of 0.05 to 1 mM reveals concentration-independent 90% monomeric and 10% dimeric populations. Extensive all-atom MD simulations at two protein concentrations, 0.9 and 8.5 mM, probe the HP36 dimer population, stability, and kinetics of dimer formation within two MD force fields, Amber ff14SB and CHARMM36m. MD results demonstrate that whereas CHARMM36m captures experimental HP36 monomer populations at the lower concentration, both force fields overly promote HP36 association at the higher concentration. Moreover, contacts stabilizing HP36 dimers are force-field-dependent. CHARMM36m produces consistently higher HP36 monomer populations, lower association rates, and weaker dependence of these quantities on the protein concentration than Amber ff14SB. Nonetheless, the highest monomer populations and dissociation constants are observed when the TIP3P water model in Amber ff14SB is replaced by TIP4P/2005, showcasing the critical role of the water model in addressing the protein solubility problem in MD.
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Affiliation(s)
- Brian Andrews
- Department of Physics, Drexel University, Philadelphia, Pennsylvania 19104, United States
| | - Kaho Long
- Department of Physics, Drexel University, Philadelphia, Pennsylvania 19104, United States
| | - Brigita Urbanc
- Department of Physics, Drexel University, Philadelphia, Pennsylvania 19104, United States
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13
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Urbanc B. Cross-Linked Amyloid β-Protein Oligomers: A Missing Link in Alzheimer's Disease Pathology? J Phys Chem B 2021; 125:1307-1316. [PMID: 33440940 DOI: 10.1021/acs.jpcb.0c07716] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Amyloid β-protein (Aβ) oligomers are broadly viewed as the proximate mediators of toxicity in Alzheimer's disease (AD). Recent studies, however, provide substantial evidence that Aβ is involved in protection and repair of the central nervous system whereby Aβ oligomer and subsequent fibril formation are integral to its normal antimicrobial and antiviral function. These developments raise a question of what exactly makes Aβ oligomers toxic in the context of AD. This Perspective describes a paradigm shift in the search for toxic Aβ oligomer species that involves oxidative-stress-induced stabilization of Aβ oligomers via cross-linking and reviews most recent research elucidating structural aspects of cross-linked Aβ oligomers and potential inhibition of their toxicity.
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Affiliation(s)
- Brigita Urbanc
- Department of Physics, Drexel University, Philadelphia, Pennsylvania 19104, United States
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14
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Cioffi F, Adam RHI, Broersen K. Molecular Mechanisms and Genetics of Oxidative Stress in Alzheimer's Disease. J Alzheimers Dis 2020; 72:981-1017. [PMID: 31744008 PMCID: PMC6971833 DOI: 10.3233/jad-190863] [Citation(s) in RCA: 102] [Impact Index Per Article: 25.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Alzheimer’s disease is the most common neurodegenerative disorder that can cause dementia in elderly over 60 years of age. One of the disease hallmarks is oxidative stress which interconnects with other processes such as amyloid-β deposition, tau hyperphosphorylation, and tangle formation. This review discusses current thoughts on molecular mechanisms that may relate oxidative stress to Alzheimer’s disease and identifies genetic factors observed from in vitro, in vivo, and clinical studies that may be associated with Alzheimer’s disease-related oxidative stress.
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Affiliation(s)
- Federica Cioffi
- Nanobiophysics Group, Technical Medical Centre, Faculty of Science and Technology, University of Twente, Enschede, The Netherlands
| | - Rayan Hassan Ibrahim Adam
- Nanobiophysics Group, Technical Medical Centre, Faculty of Science and Technology, University of Twente, Enschede, The Netherlands
| | - Kerensa Broersen
- Applied Stem Cell Technologies, Technical Medical Centre, Faculty of Science and Technology, University of Twente, Enschede, The Netherlands
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15
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Oligomerization Profile of Human Transthyretin Variants with Distinct Amyloidogenicity. Molecules 2020; 25:molecules25235698. [PMID: 33287192 PMCID: PMC7730986 DOI: 10.3390/molecules25235698] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Revised: 11/05/2020] [Accepted: 11/24/2020] [Indexed: 02/08/2023] Open
Abstract
One of the molecular hallmarks of amyloidoses is ordered protein aggregation involving the initial formation of soluble protein oligomers that eventually grow into insoluble fibrils. The identification and characterization of molecular species critical for amyloid fibril formation and disease development have been the focus of intense analysis in the literature. Here, using photo-induced cross-linking of unmodified proteins (PICUP), we studied the early stages of oligomerization of human transthyretin (TTR), a plasma protein involved in amyloid diseases (ATTR amyloidosis) with multiple clinical manifestations. Upon comparison, the oligomerization processes of wild-type TTR (TTRwt) and several TTR variants (TTRV30M, TTRL55P, and TTRT119M) clearly show distinct oligomerization kinetics for the amyloidogenic variants but a similar oligomerization mechanism. The oligomerization kinetics of the TTR amyloidogenic variants under analysis showed a good correlation with their amyloidogenic potential, with the most amyloidogenic variants aggregating faster (TTRL55P > TTRV30M > TTRwt). Moreover, the early stage oligomerization mechanism for these variants involves stepwise addition of monomeric units to the growing oligomer. A completely different behavior was observed for the nonamyloidogenic TTRT119M variant, which does not form oligomers in the same acidic conditions and even for longer incubation times. Thorough characterization of the initial steps of TTR oligomerization is critical for better understanding the origin of ATTR cytotoxicity and developing novel therapeutic strategies for the treatment of ATTR amyloidosis.
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16
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Metal- and UV- Catalyzed Oxidation Results in Trapped Amyloid-β Intermediates Revealing that Self-Assembly Is Required for Aβ-Induced Cytotoxicity. iScience 2020; 23:101537. [PMID: 33083713 PMCID: PMC7516296 DOI: 10.1016/j.isci.2020.101537] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Revised: 06/05/2020] [Accepted: 09/03/2020] [Indexed: 02/08/2023] Open
Abstract
Dityrosine (DiY), via the cross-linking of tyrosine residues, is a marker of protein oxidation, which increases with aging. Amyloid-β (Aβ) forms DiY in vitro and DiY-cross-linked Aβ is found in the brains of patients with Alzheimer disease. Metal- or UV- catalyzed oxidation of Aβ42 results in an increase in DiY cross-links. Using DiY as a marker of oxidation, we compare the self-assembly propensity and DiY cross-link formation for a non-assembly competent variant of Aβ42 (vAβ) with wild-type Aβ42. Oxidation results in the formation of trapped wild-type Aβ assemblies with increased DiY cross-links that are unable to elongate further. Assembly-incompetent vAβ and trapped Aβ assemblies are non-toxic to neuroblastoma cells at all stages of self-assembly, in contrast to oligomeric, non-cross-linked Aβ. These findings point to a mechanism of toxicity that necessitates dynamic self-assembly whereby trapped Aβ assemblies and assembly-incompetent variant Aβ are unable to result in cell death. Metal- (Cu2+ H202) or UV- catalyzedoxidation results in dityrosine (DiY) formation Oxidation results in DiY cross-link formation in Aβ and halts further assembly Non-assembling Aβ (trapped Aβ or variant Αβ monomer) is not cytotoxic
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17
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Maity S, Lyubchenko YL. AFM Probing of Amyloid-Beta 42 Dimers and Trimers. Front Mol Biosci 2020; 7:69. [PMID: 32391380 PMCID: PMC7193107 DOI: 10.3389/fmolb.2020.00069] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Accepted: 03/30/2020] [Indexed: 12/23/2022] Open
Abstract
Elucidating the molecular mechanisms in the development of such a devastating neurodegenerative disorder as Alzheimer's disease (AD) is currently one of the major challenges of molecular medicine. Evidence strongly suggests that the development of AD is due to the accumulation of amyloid β (Aβ) oligomers; therefore, understanding the molecular mechanisms defining the conversion of physiologically important monomers of Aβ proteins into neurotoxic oligomeric species is the key for the development of treatments and preventions of AD. However, these oligomers are unstable and unavailable for structural, physical, and chemical studies. We have recently developed a novel flexible nano array (FNA)-oligomer scaffold approach in which monomers tethered inside a flexible template can assemble spontaneously into oligomers with sizes defined by the number of tethered monomers. The FNA approach was tested on short decamer Aβ(14-23) peptides which were assembled into dimers and trimers. In this paper, we have extended our FNA technique for assembling full-length Aβ42 dimers. The FNA scaffold enabling the self-assembly of Aβ42 dimers from tethered monomeric species has been designed and the assembly of the dimers has been validated by AFM force spectroscopy experiments. Two major parameters of the force spectroscopy probing, the rupture forces and the rupture profiles, were obtained to prove the assembly of Aβ42 dimers. In addition, the FNA-Aβ42 dimers were used to probe Aβ42 trimers in the force spectroscopy experiments with the use of AFM tips functionalized with FNA-Aβ42 dimers and the surface with immobilized Aβ42 monomers. We found that the binding force for the Aβ42 trimer is higher than the dimer (75 ± 7 pN vs. 60 ± 3 pN) and the rupture pattern corresponds to a cooperative dissociation of the trimer. The rupture profiles for the dissociation of the Aβ42 dimers and trimers are proposed. Prospects for further extension of the FNA-based approach for probing of higher order oligomers of Aβ42 proteins are discussed.
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Affiliation(s)
| | - Yuri L. Lyubchenko
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Nebraska Medical Center, Omaha, NE, United States
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18
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Vázquez G, Caballero AB, Kokinda J, Hijano A, Sabaté R, Gamez P. Copper, dityrosine cross-links and amyloid-β aggregation. J Biol Inorg Chem 2019; 24:1217-1229. [PMID: 31667594 DOI: 10.1007/s00775-019-01734-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2019] [Accepted: 10/08/2019] [Indexed: 12/31/2022]
Abstract
Copper is involved in Alzheimer's disease (AD) where it appears to affect the aggregation of amyloid-β (Aβ) and to catalyze the production of reactive oxygen species (ROS). Oxidative stress apparently produces Aβ dimers that are covalently linked through two tyrosine residues. Such dityrosine cross-links are considered as potential markers of the disease and seem to be implicated in the pathological disorder. In the present study, pure o,o'-dityrosine (diY) was prepared enzymatically (with horseradish peroxidase; HRP), which was subsequently used to construct calibration lines aimed at quantifying nanomolar amounts of diY in reaction mixtures by fluorescence spectroscopy. Hence, diY concentrations down to 67 nM could be determined, which allowed to find that ca. 3% of dityrosine-bridged dimers of Aβ(1-40) were produced after 3 days at 37 °C in the presence of copper and dihydrogen peroxide. These cross-linked dimers in the presence of copper(II) ions completely inhibit the typical aggregation of Aβ, since β sheets could not be detected applying the usual Thioflavin T (ThT) method. Furthermore, the use of a potent Cu(II) chelator, such as the ATCUN tripeptide, L-histidyl-L-alanyl-L-histidine (HAH), efficiently prevented the copper-mediated generation of ROS and the associated dityrosine-bridged Aβ dimers, suggesting that such metal chelators may find future applications in the field of anti-AD drug design.
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Affiliation(s)
- Guillem Vázquez
- Inorganic Chemistry Section, Department of Inorganic and Organic Chemistry, University of Barcelona, Martí i Franquès 1-11, 08028, Barcelona, Spain
| | - Ana B Caballero
- Inorganic Chemistry Section, Department of Inorganic and Organic Chemistry, University of Barcelona, Martí i Franquès 1-11, 08028, Barcelona, Spain. .,Institute of Nanoscience and Nanotechnology (IN2UB), Universitat de Barcelona, Barcelona, Spain.
| | - Jakub Kokinda
- Inorganic Chemistry Section, Department of Inorganic and Organic Chemistry, University of Barcelona, Martí i Franquès 1-11, 08028, Barcelona, Spain
| | - Ana Hijano
- Inorganic Chemistry Section, Department of Inorganic and Organic Chemistry, University of Barcelona, Martí i Franquès 1-11, 08028, Barcelona, Spain
| | - Raimon Sabaté
- Institute of Nanoscience and Nanotechnology (IN2UB), Universitat de Barcelona, Barcelona, Spain. .,Departament de Fisicoquímica, Facultat de Farmàcia i Ciències de l'Alimentació, Universitat de Barcelona, Avda. Joan XXIII 27-31, 08028, Barcelona, Spain.
| | - Patrick Gamez
- Inorganic Chemistry Section, Department of Inorganic and Organic Chemistry, University of Barcelona, Martí i Franquès 1-11, 08028, Barcelona, Spain. .,Institute of Nanoscience and Nanotechnology (IN2UB), Universitat de Barcelona, Barcelona, Spain. .,Catalan Institution for Research and Advanced Studies (ICREA), Passeig Lluís Companys 23, 08010, Barcelona, Spain.
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19
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Long K, Williams TL, Urbanc B. Insulin Inhibits Aβ42 Aggregation and Prevents Aβ42-Induced Membrane Disruption. Biochemistry 2019; 58:4519-4529. [DOI: 10.1021/acs.biochem.9b00696] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Kaho Long
- Department of Physics, Drexel University, Philadelphia, Pennsylvania 19104, United States
| | | | - Brigita Urbanc
- Department of Physics, Drexel University, Philadelphia, Pennsylvania 19104, United States
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20
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Metal binding to the amyloid-β peptides in the presence of biomembranes: potential mechanisms of cell toxicity. J Biol Inorg Chem 2019; 24:1189-1196. [PMID: 31562546 DOI: 10.1007/s00775-019-01723-9] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2019] [Accepted: 09/10/2019] [Indexed: 12/18/2022]
Abstract
The amyloid-β (Aβ) peptides are key molecules in Alzheimer's disease (AD) pathology. They interact with cellular membranes, and can bind metal ions outside the membrane. Certain oligomeric Aβ aggregates are known to induce membrane perturbations and the structure of these oligomers-and their membrane-perturbing effects-can be modulated by metal ion binding. If the bound metal ions are redox active, as e.g., Cu and Fe ions are, they will generate harmful reactive oxygen species (ROS) just outside the membrane surface. Thus, the membrane damage incurred by toxic Aβ oligomers is likely aggravated when redox-active metal ions are present. The combined interactions between Aβ oligomers, metal ions, and biomembranes may be responsible for at least some of the neuronal death in AD patients.
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21
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Nguyen PH, Campanera JM, Ngo ST, Loquet A, Derreumaux P. Tetrameric Aβ40 and Aβ42 β-Barrel Structures by Extensive Atomistic Simulations. II. In Aqueous Solution. J Phys Chem B 2019; 123:6750-6756. [DOI: 10.1021/acs.jpcb.9b05288] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- 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, France
| | - Josep M. Campanera
- Departament de Fisicoquímica, Facultat de Farmacia, Universitat de Barcelona, 08028 Barcelona, Catalonia, Spain
| | - 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
| | - Antoine Loquet
- Institute of Chemistry and Biology of Membranes and Nanoobjects, UMR5248 CNRS, Université de Bordeaux, Bordeaux, 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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22
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Cline EN, Das A, Bicca MA, Mohammad SN, Schachner LF, Kamel JM, DiNunno N, Weng A, Paschall JD, Bu RL, Khan FM, Rollins MG, Ives AN, Shekhawat G, Nunes-Tavares N, de Mello FG, Compton PD, Kelleher NL, Klein WL. A novel crosslinking protocol stabilizes amyloid β oligomers capable of inducing Alzheimer's-associated pathologies. J Neurochem 2019; 148:822-836. [PMID: 30565253 DOI: 10.1111/jnc.14647] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2018] [Revised: 12/09/2018] [Accepted: 12/11/2018] [Indexed: 12/27/2022]
Abstract
Amyloid β oligomers (AβOs) accumulate early in Alzheimer's disease (AD) and experimentally cause memory dysfunction and the major pathologies associated with AD, for example, tau abnormalities, synapse loss, oxidative damage, and cognitive dysfunction. In order to develop the most effective AβO-targeting diagnostics and therapeutics, the AβO structures contributing to AD-associated toxicity must be elucidated. Here, we investigate the structural properties and pathogenic relevance of AβOs stabilized by the bifunctional crosslinker 1,5-difluoro-2,4-dinitrobenzene (DFDNB). We find that DFDNB stabilizes synthetic Aβ in a soluble oligomeric conformation. With DFDNB, solutions of Aβ that would otherwise convert to large aggregates instead yield solutions of stable AβOs, predominantly in the 50-300 kDa range, that are maintained for at least 12 days at 37°C. Structures were determined by biochemical and native top-down mass spectrometry analyses. Assayed in neuronal cultures and i.c.v.-injected mice, the DFDNB-stabilized AβOs were found to induce tau hyperphosphorylation, inhibit choline acetyltransferase, and provoke neuroinflammation. Most interestingly, DFDNB crosslinking was found to stabilize an AβO conformation particularly potent in inducing memory dysfunction in mice. Taken together, these data support the utility of DFDNB crosslinking as a tool for stabilizing pathogenic AβOs in structure-function studies.
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Affiliation(s)
- Erika N Cline
- Department of Neurobiology, Northwestern University, Evanston, Illinois, USA
| | - Arighno Das
- Department of Neurobiology, Northwestern University, Evanston, Illinois, USA
| | | | - Saad N Mohammad
- Department of Neurobiology, Northwestern University, Evanston, Illinois, USA.,Department of Chemical and Biological Engineering, Northwestern University, Evanston, Illinois, USA
| | - Luis F Schachner
- Departments of Chemistry and Molecular Biosciences and the Proteomics Center of Excellence, Northwestern University, Evanston, Illinois, USA
| | - Josette M Kamel
- Department of Neurobiology, Northwestern University, Evanston, Illinois, USA
| | - Nadia DiNunno
- Department of Neurobiology, Northwestern University, Evanston, Illinois, USA
| | - Anthea Weng
- Department of Neurobiology, Northwestern University, Evanston, Illinois, USA
| | - Jacob D Paschall
- Department of Neurobiology, Northwestern University, Evanston, Illinois, USA
| | - Riana Lo Bu
- Department of Neurobiology, Northwestern University, Evanston, Illinois, USA
| | - Faraz M Khan
- Department of Neurobiology, Northwestern University, Evanston, Illinois, USA
| | - Madeline G Rollins
- Department of Neurobiology, Northwestern University, Evanston, Illinois, USA
| | - Ashley N Ives
- Departments of Chemistry and Molecular Biosciences and the Proteomics Center of Excellence, Northwestern University, Evanston, Illinois, USA
| | - Gajendra Shekhawat
- Department of Material Science and Engineering, Northwestern University, Evanston, Illinois, USA
| | - Nilson Nunes-Tavares
- Instituo de Biofisica Carlo Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Fernando G de Mello
- Instituo de Biofisica Carlo Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Philip D Compton
- Departments of Chemistry and Molecular Biosciences and the Proteomics Center of Excellence, Northwestern University, Evanston, Illinois, USA
| | - Neil L Kelleher
- Departments of Chemistry and Molecular Biosciences and the Proteomics Center of Excellence, Northwestern University, Evanston, Illinois, USA
| | - William L Klein
- Department of Neurobiology, Northwestern University, Evanston, Illinois, USA
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23
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Zhang S, Fox DM, Urbanc B. Elucidating the Role of Hydroxylated Phenylalanine in the Formation and Structure of Cross-Linked Aβ Oligomers. J Phys Chem B 2019; 123:1068-1084. [DOI: 10.1021/acs.jpcb.8b12120] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Affiliation(s)
- Shuting Zhang
- Department of Physics, Drexel University, Philadelphia, Pennsylvania 19104, United States
| | - Dillion M. Fox
- Department of Physics, Drexel University, Philadelphia, Pennsylvania 19104, United States
| | - Brigita Urbanc
- Department of Physics, Drexel University, Philadelphia, Pennsylvania 19104, United States
- Faculty of Mathematics and Physics, University of Ljubljana, Ljubljana, Slovenia
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24
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Copper Redox Cycling Inhibits Aβ Fibre Formation and Promotes Fibre Fragmentation, while Generating a Dityrosine Aβ Dimer. Sci Rep 2018; 8:16190. [PMID: 30385800 PMCID: PMC6212427 DOI: 10.1038/s41598-018-33935-5] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2018] [Accepted: 10/04/2018] [Indexed: 12/22/2022] Open
Abstract
Oxidative stress and the formation of plaques which contain amyloid-β (Aβ) peptides are two key hallmarks of Alzheimer’s disease (AD). Dityrosine is found in the plaques of AD patients and Aβ dimers have been linked to neurotoxicity. Here we investigate the formation of Aβ dityrosine dimers promoted by Cu2+/+ Fenton reactions. Using fluorescence measurements and UV absorbance, we show that dityrosine can be formed aerobically when Aβ is incubated with Cu2+ and hydrogen-peroxide, or in a Cu2+ and ascorbate redox mixture. The dityrosine cross-linking can occur for both monomeric and fibrillar forms of Aβ. We show that oxidative modification of Aβ impedes the ability for Aβ monomer to form fibres, as indicated by the amyloid specific dye Thioflavin T (ThT). Transmission electron microscopy (TEM) indicates the limited amyloid assemblies that form have a marked reduction in fibre length for Aβ(1–40). Importantly, the addition of Cu2+ and a reductant to preformed Aβ(1–40) fibers causes their widespread fragmentation, reducing median fibre lengths from 800 nm to 150 nm upon oxidation. The processes of covalent cross-linking of Aβ fibres, dimer formation, and fibre fragmentation within plaques are likely to have a significant impact on Aβ clearance and neurotoxicity.
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25
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Vázquez de la Torre A, Gay M, Vilaprinyó-Pascual S, Mazzucato R, Serra-Batiste M, Vilaseca M, Carulla N. Direct Evidence of the Presence of Cross-Linked Aβ Dimers in the Brains of Alzheimer’s Disease Patients. Anal Chem 2018. [DOI: 10.1021/acs.analchem.7b04936] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- Aurelio Vázquez de la Torre
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology (BIST), Baldiri Reixac 10, 08028 Barcelona, Spain
| | - Marina Gay
- Mass Spectrometry and Proteomics Core Facility, Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology (BIST), Baldiri Reixac 10, 08028 Barcelona, Spain
| | - Sílvia Vilaprinyó-Pascual
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology (BIST), Baldiri Reixac 10, 08028 Barcelona, Spain
| | - Roberta Mazzucato
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology (BIST), Baldiri Reixac 10, 08028 Barcelona, Spain
| | - Montserrat Serra-Batiste
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology (BIST), Baldiri Reixac 10, 08028 Barcelona, Spain
| | - Marta Vilaseca
- Mass Spectrometry and Proteomics Core Facility, Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology (BIST), Baldiri Reixac 10, 08028 Barcelona, Spain
| | - Natàlia Carulla
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology (BIST), Baldiri Reixac 10, 08028 Barcelona, Spain
- CBMN (UMR 5248), University of Bordeaux − CNRS − IPB, Institut Européen de Chimie et Biologie, 2 rue Escarpit, 33600 Pessac, France
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26
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Lessons learned from protein aggregation: toward technological and biomedical applications. Biophys Rev 2017; 9:501-515. [PMID: 28905328 DOI: 10.1007/s12551-017-0317-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2017] [Accepted: 08/08/2017] [Indexed: 12/21/2022] Open
Abstract
The close relationship between protein aggregation and neurodegenerative diseases has been the driving force behind the renewed interest in a field where biophysics, neurobiology and nanotechnology converge in the study of the aggregate state. On one hand, knowledge of the molecular principles that govern the processes of protein aggregation has a direct impact on the design of new drugs for high-incidence pathologies that currently can only be treated palliatively. On the other hand, exploiting the benefits of protein aggregation in the design of new nanomaterials could have a strong impact on biotechnology. Here we review the contributions of our research group on novel neuroprotective strategies developed using a purely biophysical approach. First, we examine how doxycycline, a well-known and innocuous antibiotic, can reshape α-synuclein oligomers into non-toxic high-molecular-weight species with decreased ability to destabilize biological membranes, affect cell viability and form additional toxic species. This mechanism can be exploited to diminish the toxicity of α-synuclein oligomers in Parkinson's disease. Second, we discuss a novel function in proteostasis for extracellular glyceraldehyde 3-phosphate dehydrogenase (GAPDH) in combination with a specific glycosaminoglycan (GAG) present in the extracellular matrix. GAPDH, by changing its quaternary structure from a tetramer to protofibrillar assembly, can kidnap toxic species of α-synuclein, and thereby interfere with the spreading of the disease. Finally, we review a brighter side of protein aggregation, that of exploiting the physicochemical advantages of amyloid aggregates as nanomaterials. For this, we designed a new generation of insoluble biocatalysts based on the binding of photo-immobilized enzymes onto hybrid protein:GAG amyloid nanofibrils. These new nanomaterials can be easily functionalized by attaching different enzymes through dityrosine covalent bonds.
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27
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Lai L, Jiang X, Han S, Zhao C, Du T, Rehman FU, Zheng Y, Li X, Liu X, Jiang H, Wang X. In Vivo Biosynthesized Zinc and Iron Oxide Nanoclusters for High Spatiotemporal Dual-Modality Bioimaging of Alzheimer's Disease. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2017; 33:9018-9024. [PMID: 28806518 DOI: 10.1021/acs.langmuir.7b01516] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Alzheimer's disease is still incurable and neurodegenerative, and there is a lack of detection methods with high sensitivity and specificity. In this study, by taking different month old Alzheimer's mice as models, we have explored the possibility of the target bioimaging of diseased sites through the initial injection of zinc gluconate solution into Alzheimer's model mice post-tail vein and then the combination of another injection of ferrous chloride (FeCl2) solution into the same Alzheimer's model mice post-stomach. Our observations indicate that both zinc gluconate solution and FeCl2 solution could cross the blood-brain barrier (BBB) to biosynthesize the fluorescent zinc oxide nanoclusters and magnetic iron oxide nanoclusters, respectively, in the lesion areas of the AD model mice, thus enabling high spatiotemporal dual-modality bioimaging (i.e., including fluorescence bioimaging (FL) and magnetic resonance imaging (MRI)) of Alzheimer's disease for the first time. The result presents a novel promising strategy for the rapid and early diagnosis of Alzheimer's disease.
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Affiliation(s)
- Lanmei Lai
- State Key Laboratory of Bioelectronics, National Demonstration Center for Experimental Biomedical Engineering Education, School of Biological Science and Medical Engineering, Southeast University , Nanjing 210096, China
| | - Xuerui Jiang
- State Key Laboratory of Bioelectronics, National Demonstration Center for Experimental Biomedical Engineering Education, School of Biological Science and Medical Engineering, Southeast University , Nanjing 210096, China
| | - Shanying Han
- State Key Laboratory of Bioelectronics, National Demonstration Center for Experimental Biomedical Engineering Education, School of Biological Science and Medical Engineering, Southeast University , Nanjing 210096, China
| | - Chunqiu Zhao
- State Key Laboratory of Bioelectronics, National Demonstration Center for Experimental Biomedical Engineering Education, School of Biological Science and Medical Engineering, Southeast University , Nanjing 210096, China
| | - Tianyu Du
- State Key Laboratory of Bioelectronics, National Demonstration Center for Experimental Biomedical Engineering Education, School of Biological Science and Medical Engineering, Southeast University , Nanjing 210096, China
| | - Fawad Ur Rehman
- State Key Laboratory of Bioelectronics, National Demonstration Center for Experimental Biomedical Engineering Education, School of Biological Science and Medical Engineering, Southeast University , Nanjing 210096, China
| | - Youkun Zheng
- State Key Laboratory of Bioelectronics, National Demonstration Center for Experimental Biomedical Engineering Education, School of Biological Science and Medical Engineering, Southeast University , Nanjing 210096, China
| | - Xiaoqi Li
- Nanjing Foreign Language School, Nanjing 210096, China
| | - Xiaoli Liu
- State Key Laboratory of Bioelectronics, National Demonstration Center for Experimental Biomedical Engineering Education, School of Biological Science and Medical Engineering, Southeast University , Nanjing 210096, China
| | - Hui Jiang
- State Key Laboratory of Bioelectronics, National Demonstration Center for Experimental Biomedical Engineering Education, School of Biological Science and Medical Engineering, Southeast University , Nanjing 210096, China
| | - Xuemei Wang
- State Key Laboratory of Bioelectronics, National Demonstration Center for Experimental Biomedical Engineering Education, School of Biological Science and Medical Engineering, Southeast University , Nanjing 210096, China
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28
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Mawhinney MT, Williams TL, Hart JL, Taheri ML, Urbanc B. Elucidation of insulin assembly at acidic and neutral pH: Characterization of low molecular weight oligomers. Proteins 2017; 85:2096-2110. [PMID: 28796342 DOI: 10.1002/prot.25365] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2017] [Revised: 07/18/2017] [Accepted: 07/26/2017] [Indexed: 12/13/2022]
Abstract
Deficiency in insulin secretion and function that characterize type 2 diabetes often requires administration of extraneous insulin, leading to injection-site amyloidosis. Insulin aggregation at neutral pH is not well understood. Although oligomer formation is believed to play an important role, insulin oligomers have not been fully characterized yet. Here, we elucidate similarities and differences between in vitro insulin aggregation at acidic and neutral pH for a range of insulin concentrations (2.5-100 μM) by using kinetic thioflavin T fluorescence, circular dichroism, atomic force and electron microscopy imaging. Importantly, we characterize the size distribution of insulin oligomers at different assembly stages by the application of covalent cross-linking and gel electrophoresis. Our results show that at the earliest assembly stage, oligomers comprise up to 40% and 70% of soluble insulin at acidic and neutral pH, respectively. While the highest oligomer order increases with insulin concentration at acidic pH, the opposite tendency is observed at neutral pH, where oligomers up to heptamers are formed in 10 μM insulin. These findings suggest that oligomers may be on- and off-pathway assemblies for insulin at acidic and neutral pH, respectively. Agitation, which is required to induce insulin aggregation at neutral pH, is shown to increase fibril formation rate and fibrillar mass both by an order of magnitude. Insulin incubated under agitated conditions at neutral pH rapidly aggregates into large micrometer-sized aggregates, which may be of physiological relevance and provides insight into injection-site amyloidosis and toxic pulmonary aggregates induced by administration of extraneous insulin.
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Affiliation(s)
| | - Thomas L Williams
- Department of Physics, Drexel University, Philadelphia, PA, USA.,Clarivate Analytics, 1500 Spring Garden Street, Philadelphia, PA, USA
| | - James L Hart
- Department of Materials Science and Engineering, Drexel University, Philadelphia, PA, USA
| | - Mitra L Taheri
- Department of Materials Science and Engineering, Drexel University, Philadelphia, PA, USA
| | - Brigita Urbanc
- Department of Physics, Drexel University, Philadelphia, PA, USA.,Faculty of Mathematics and Physics, Jadranska ulica 19, Ljubljana, 1000, Slovenia
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29
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Voelker MJ, Barz B, Urbanc B. Fully Atomistic Aβ40 and Aβ42 Oligomers in Water: Observation of Porelike Conformations. J Chem Theory Comput 2017; 13:4567-4583. [DOI: 10.1021/acs.jctc.7b00495] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- Matthew J. Voelker
- Department
of Physics, Drexel University, Philadelphia, Pennsylvania 19104, United States
| | - Bogdan Barz
- Institute
of Complex Systems, Structural Biochemistry ICS-6: Structural Biochemistry, Forschungzentrum Jülich GmbH, Jülich 52425, Germany
- Institute
of Theoretical and Computational Chemistry, Heinrich Heine University Düsseldorf, Düsseldorf 40225, Germany
| | - Brigita Urbanc
- Department
of Physics, Drexel University, Philadelphia, Pennsylvania 19104, United States
- Faculty
of Mathematics and Physics, University of Ljubljana, Ljubljana 1000, Slovenia
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30
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Man VH, Nguyen PH, Derreumaux P. High-Resolution Structures of the Amyloid-β 1-42 Dimers from the Comparison of Four Atomistic Force Fields. J Phys Chem B 2017; 121:5977-5987. [PMID: 28538095 DOI: 10.1021/acs.jpcb.7b04689] [Citation(s) in RCA: 110] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The dimer of the amyloid-β peptide Aβ of 42 residues is the smallest toxic species in Alzheimer's disease, but its equilibrium structures are unknown. Here we determined the equilibrium ensembles generated by the four atomistic OPLS-AA, CHARMM22*, AMBER99sb-ildn, and AMBERsb14 force fields with the TIP3P water model. On the basis of 144 μs replica exchange molecular dynamics simulations (with 750 ns per replica), we find that the four force fields lead to random coil ensembles with calculated cross-collision sections, hydrodynamics properties, and small-angle X-ray scattering profiles independent of the force field. There are, however, marked differences in secondary structure, with the AMBERsb14 and CHARMM22* ensembles overestimating the CD-derived helix content, and the OPLS-AA and AMBER99sb-ildn secondary structure contents in agreement with CD data. Also the intramolecular beta-hairpin content spanning residues 17-21 and 30-36 varies between 1.5% and 13%. Overall, there are significant differences in tertiary and quaternary conformations among all force fields, and the key finding, irrespective of the force field, is that the dimer is stabilized by nonspecific interactions, explaining therefore its possible transient binding to multiple cellular partners and, in part, its toxicity.
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Affiliation(s)
- Viet Hoang Man
- Department of Physics, North Carolina State University , Raleigh, North Carolina 27695-8202, United States
| | - Phuong H Nguyen
- Laboratoire de Biochimie Théorique, UPR 9080 CNRS, Université Paris Diderot , Sorbonne Paris Cité, IBPC, 13 Rue Pierre et Marie Curie, 75005 Paris, France
| | - Philippe Derreumaux
- Laboratoire de Biochimie Théorique, UPR 9080 CNRS, Université Paris Diderot , Sorbonne Paris Cité, IBPC, 13 Rue Pierre et Marie Curie, 75005 Paris, France
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31
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Zhang S, Fox DM, Urbanc B. Insights into Formation and Structure of Aβ Oligomers Cross-Linked via Tyrosines. J Phys Chem B 2017; 121:5523-5535. [DOI: 10.1021/acs.jpcb.7b02495] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Shuting Zhang
- Department
of Physics, Drexel University, Philadelphia, Pennsylvania 19104, United States
| | - Dillion M. Fox
- Department
of Physics, Drexel University, Philadelphia, Pennsylvania 19104, United States
| | - Brigita Urbanc
- Department
of Physics, Drexel University, Philadelphia, Pennsylvania 19104, United States
- Faculty
of Mathematics and Physics, University of Ljubljana, 1000 Ljubljana, Slovenia
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32
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Synthetic toxic Aβ 1–42 oligomers can assemble in different morphologies. Biochim Biophys Acta Gen Subj 2017; 1861:1168-1176. [DOI: 10.1016/j.bbagen.2017.03.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2016] [Revised: 02/21/2017] [Accepted: 03/01/2017] [Indexed: 12/28/2022]
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33
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Goldblatt G, Cilenti L, Matos JO, Lee B, Ciaffone N, Wang QX, Tetard L, Teter K, Tatulian SA. Unmodified and pyroglutamylated amyloid β peptides form hypertoxic hetero-oligomers of unique secondary structure. FEBS J 2017; 284:1355-1369. [PMID: 28294556 DOI: 10.1111/febs.14058] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2016] [Revised: 03/07/2017] [Accepted: 03/08/2017] [Indexed: 11/29/2022]
Abstract
Amyloid β (Aβ) peptide plays a major role in Alzheimer's disease (AD) and occurs in multiple forms, including pyroglutamylated Aβ (AβpE). Identification and characterization of the most cytotoxic Aβ species is necessary for advancement in AD diagnostics and therapeutics. While in brain tissue multiple Aβ species act in combination, structure/toxicity studies and immunotherapy trials have been focused on individual forms of Aβ. As a result, the molecular composition and the structural features of "toxic Aβ oligomers" have remained unresolved. Here, we have used a novel approach, hydration from gas phase coupled with isotope-edited Fourier transform infrared (FTIR) spectroscopy, to identify the prefibrillar assemblies formed by Aβ and AβpE and to resolve the structures of both peptides in combination. The peptides form unusual β-sheet oligomers stabilized by intramolecular H-bonding as opposed to intermolecular H-bonding in the fibrils. Time-dependent morphological changes in peptide assemblies have been visualized by atomic force microscopy. Aβ/AβpE hetero-oligomers exert unsurpassed cytotoxic effect on PC12 cells as compared to oligomers of individual peptides or fibrils. These findings lead to a novel concept that Aβ/AβpE hetero-oligomers, not just Aβ or AβpE oligomers, constitute the main neurotoxic conformation. The hetero-oligomers thus present a new biomarker that may be targeted for development of more efficient diagnostic and immunotherapeutic strategies to combat AD.
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Affiliation(s)
- Greg Goldblatt
- Biomedical Sciences Graduate Program, University of Central Florida, Orlando, FL, USA
| | - Lucia Cilenti
- Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, FL, USA
| | - Jason O Matos
- Biotechnology Graduate Program, University of Central Florida, Orlando, FL, USA
| | - Briana Lee
- Nanotechnology Graduate Program, NanoScience Technology Center, University of Central Florida, Orlando, FL, USA
| | - Nicholas Ciaffone
- Nanotechnology Graduate Program, NanoScience Technology Center, University of Central Florida, Orlando, FL, USA
| | - Qing X Wang
- Physics Graduate Program, College of Sciences, University of Central Florida, Orlando, FL, USA
| | - Laurene Tetard
- NanoScience Technology Center, University of Central Florida, Orlando, FL, USA.,Department of Physics, College of Sciences, University of Central Florida, Orlando, FL, USA
| | - Ken Teter
- Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando, FL, USA
| | - Suren A Tatulian
- Department of Physics, College of Sciences, University of Central Florida, Orlando, FL, USA
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34
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Urbanc B. Flexible N‐Termini of Amyloid β‐Protein Oligomers: A Link between Structure and Activity? Isr J Chem 2017. [DOI: 10.1002/ijch.201600097] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Affiliation(s)
- Brigita Urbanc
- Department of Physics Drexel University Philadelphia, PA 19104 USA
- Faculty of Mathematics and Physics Jadranska ulica 19 1000 Ljubljana Slovenia
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35
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Žerovnik E. Putative alternative functions of human stefin B (cystatin B): binding to amyloid-beta, membranes, and copper. J Mol Recognit 2016; 30. [PMID: 27577977 DOI: 10.1002/jmr.2562] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2016] [Revised: 07/25/2016] [Accepted: 07/26/2016] [Indexed: 12/17/2022]
Abstract
We describe studies performed thus far on stefin B from the family of cystatins as a model protein for folding and amyloid fibril formation studies. We also briefly mention our studies on aggregation of some of the missense EPM1 mutants of stefin B in cells, which mimic additional pathological traits (gain in toxic function) in selected patients with EPM1 disease. We collected data on the reported interactors of stefin B and discuss several hypotheses of possible cytosolic alternative functions.
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Affiliation(s)
- Eva Žerovnik
- Department of Biochemistry and Molecular and Structural Biology, Jožef Stefan Institute, Ljubljana, Slovenia.,CipKeBip-Centre of Excellence for Integrated Approaches in Chemistry and Biology of Proteins, Ljubljana, Slovenia
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36
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Amino acid substitutions [K16A] and [K28A] distinctly affect amyloid β-protein oligomerization. J Biol Phys 2016; 42:453-76. [PMID: 27155979 DOI: 10.1007/s10867-016-9417-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2016] [Accepted: 03/28/2016] [Indexed: 10/21/2022] Open
Abstract
Amyloid β-protein (A β) assembles into oligomers that play a seminal role in Alzheimer's disease (AD), a leading cause of dementia among the elderly. Despite undisputed importance of A β oligomers, their structure and the basis of their toxicity remain elusive. Previous experimental studies revealed that the [K16A] substitution strongly inhibits toxicity of the two predominant A β alloforms in the brain, A β 40 and A β 42, whereas the [K28A] substitution exerts only a moderate effect. Here, folding and oligomerization of [A16]A β 40, [A28]A β 40, [A16]A β 42, and [A28]A β 42 are examined by discrete molecular dynamics (DMD) combined with a four-bead implicit solvent force field, DMD4B-HYDRA, and compared to A β 40 and A β 42 oligomer formation. Our results show that both substitutions promote A β 40 and A β 42 oligomerization and that structural changes to oligomers are substitution- and alloform-specific. The [K28A] substitution increases solvent-accessible surface area of hydrophobic residues and the intrapeptide N-to-C terminal distance within oligomers more than the [K16A] substitution. The [K16A] substitution decreases the overall β-strand content, whereas the [K28A] substitution exerts only a modest change. Substitution-specific tertiary and quaternary structure changes indicate that the [K16A] substitution induces formation of more compact oligomers than the [K28A] substitution. If the structure-function paradigm applies to A β oligomers, then the observed substitution-specific structural changes in A β 40 and A β 42 oligomers are critical for understanding the structural basis of A β oligomer toxicity and correct identification of therapeutic targets against AD.
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