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Kell DB, Pretorius E. Are fibrinaloid microclots a cause of autoimmunity in Long Covid and other post-infection diseases? Biochem J 2023; 480:1217-1240. [PMID: 37584410 DOI: 10.1042/bcj20230241] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2023] [Revised: 08/03/2023] [Accepted: 08/07/2023] [Indexed: 08/17/2023]
Abstract
It is now well established that the blood-clotting protein fibrinogen can polymerise into an anomalous form of fibrin that is amyloid in character; the resultant clots and microclots entrap many other molecules, stain with fluorogenic amyloid stains, are rather resistant to fibrinolysis, can block up microcapillaries, are implicated in a variety of diseases including Long COVID, and have been referred to as fibrinaloids. A necessary corollary of this anomalous polymerisation is the generation of novel epitopes in proteins that would normally be seen as 'self', and otherwise immunologically silent. The precise conformation of the resulting fibrinaloid clots (that, as with prions and classical amyloid proteins, can adopt multiple, stable conformations) must depend on the existing small molecules and metal ions that the fibrinogen may (and is some cases is known to) have bound before polymerisation. Any such novel epitopes, however, are likely to lead to the generation of autoantibodies. A convergent phenomenology, including distinct conformations and seeding of the anomalous form for initiation and propagation, is emerging to link knowledge in prions, prionoids, amyloids and now fibrinaloids. We here summarise the evidence for the above reasoning, which has substantial implications for our understanding of the genesis of autoimmunity (and the possible prevention thereof) based on the primary process of fibrinaloid formation.
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Affiliation(s)
- Douglas B Kell
- Department of Biochemistry, Cell and Systems Biology, Institute of Systems, Molecular and Integrative Biology, Faculty of Health and Life Sciences, University of Liverpool, Liverpool L69 7ZB, U.K
- The Novo Nordisk Foundation Centre for Biosustainability, Technical University of Denmark, Kemitorvet 200, 2800 Kgs Lyngby, Denmark
- Department of Physiological Sciences, Faculty of Science, Stellenbosch University, Private Bag X1 Matieland, Stellenbosch 7602, South Africa
| | - Etheresia Pretorius
- Department of Biochemistry, Cell and Systems Biology, Institute of Systems, Molecular and Integrative Biology, Faculty of Health and Life Sciences, University of Liverpool, Liverpool L69 7ZB, U.K
- Department of Physiological Sciences, Faculty of Science, Stellenbosch University, Private Bag X1 Matieland, Stellenbosch 7602, South Africa
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2
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Heath SL, Horne WS, Lengyel GA. Effects of chirality and side chain length in C α,α-dialkylated residues on β-hairpin peptide folded structure and stability. Org Biomol Chem 2023; 21:6320-6324. [PMID: 37503895 PMCID: PMC10445279 DOI: 10.1039/d3ob00963g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/29/2023]
Abstract
Strategic incorporation of achiral Cα,α-dialkylated amino acids with bulky substituents into peptides can be used to promote extended strand conformations and inhibit protein-protein interactions associated with amyloid formation. In this work, we evaluate the thermodynamic impact of chiral Cα,α monomers on folding preferences in such systems through introduction of a series of Cα-methylated and Cα-ethylated residues into a β-hairpin host sequence. Depending on stereochemical configuration of the artificial monomer and potential for additional hydrophobic packing, a Cα-ethyl-Cα-propyl glycine residue can provide similar or enhanced folded stability relative to an achiral Cα,α-diethyl analogue.
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Affiliation(s)
- Shelby L Heath
- Department of Chemistry, University of Pittsburgh, Pittsburgh, PA 15260, USA
| | - W Seth Horne
- Department of Chemistry, University of Pittsburgh, Pittsburgh, PA 15260, USA
| | - George A Lengyel
- Department of Chemistry, Slippery Rock University, Slippery Rock, PA 16057, USA.
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3
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Zbacnik NJ, Manning MC, Henry CS. Chemometric Study of the Relative Aggregation Propensity of Position 19
Mutants of Aβ(1-42). Curr Protein Pept Sci 2022; 23:52-60. [DOI: 10.2174/1389203723666220128105334] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Revised: 12/12/2021] [Accepted: 12/13/2021] [Indexed: 11/22/2022]
Abstract
Background:
The importance of aromaticity vs. hydrophobicity of the central hydrophobic
core (CHC, residues 17-20) in governing fibril formation in Aβ(1-42) has been the focus of an ongoing
debate in the literature.
Introduction:
Mutations in the CHC (especially at Phe19 and Phe20) have been used to examine the
relative impact of hydrophobicity and aromaticity on the degree of aggregation of Aβ(1-42). However,
the results have not been conclusive.
Methods:
Partial least squares (PLS) modeling of aggregation rates, using reduced properties of a series
of position 19 mutants, was employed to identify the physicochemical properties that had the
greatest impact on the extent of aggregation.
Results:
The PLS models indicate that hydrophobicity at position 19 of Aβ(1-42) appears to be the
primary and dominant factor in controlling Aβ(1-42) aggregation, with aromaticity having little effect.
Conclusions:
This study illustrates the value of using reduced properties of amino acids in conjunction
with PLS modeling to investigate mutational effects in peptides and proteins, as the reduced properties
can capture in a quantitative manner the different physicochemical properties of the amino acid side
chains. In this particular study, hydrophobicity at position 19 was determined to be the dominant property
controlling aggregation, while size, charge, and aromaticity had little impact.
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Affiliation(s)
| | - Mark Cornell Manning
- Legacy BioDesign LLC, Johnstown, CO 80534, USA
- Department of Chemistry, Colorado State University, Fort Collins, CO 80523, USA
| | - Charles S. Henry
- Department of Chemistry, Colorado State University, Fort Collins, CO 80523, USA
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4
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Łagiewka J, Girek T, Ciesielski W. Cyclodextrins-Peptides/Proteins Conjugates: Synthesis, Properties and Applications. Polymers (Basel) 2021; 13:1759. [PMID: 34072062 PMCID: PMC8198514 DOI: 10.3390/polym13111759] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 05/19/2021] [Accepted: 05/25/2021] [Indexed: 12/24/2022] Open
Abstract
Cyclodextrins (CDs) are a family of macrocyclic oligosaccharides mostly composed of six, seven, or eight α-D-glucopyranose units with α-1,4-glycosidic bonds to form toroidal structures. The CDs possess a hydrophilic exterior and hydrophobic interior with the ability to form an inclusion complex, especially with hydrophobic molecules. However, most existing studies are about conjugation CDs with peptide/protein focusing on the formation of new systems. The CD-peptide/protein can possess new abilities; particularly, the cavity can be applied in modulation properties of more complexed proteins. Most studies are focused on drug delivery, such as targeted delivery in cell-penetrating peptides or co-delivery. The co-delivery is based mostly on polylysine systems; on the other hand, the CD-peptide allows us to understand biomolecular mechanisms such as fibryllation or stem cell behaviour. Moreover, the CD-proteins are more complexed systems with a focus on targeted therapy; these conjugates might be controllable with various properties due to changes in their stability. Finally, the studies of CD-peptide/protein are promising in biomedical application and provide new possibilities for the conjugation of simple molecules to biomolecules.
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Affiliation(s)
- Jakub Łagiewka
- Faculty of Mathematics and Natural Science, Jan Dlugosz University in Czestochowa, Armii Krajowej Ave., 13/15, 42 201 Czestochowa, Poland; (T.G.); (W.C.)
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5
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dos Santos RV, Vitoi VHM, Costa MV, da Silva LCLLF, Archanjo BS, Achete CA, Silva RSF, Aguiar LCS, Malta LFB, Senra JD. Thermoresponsive Starch Hydrogel Stabilized Pd Nanoparticles: Soft Catalyst for the Preparation of (±)-α-Methylbiphenylalanine in Water Aiming at Bioorthogonal Chemistries. Catal Letters 2020. [DOI: 10.1007/s10562-020-03350-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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6
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Laxio Arenas J, Kaffy J, Ongeri S. Peptides and peptidomimetics as inhibitors of protein–protein interactions involving β-sheet secondary structures. Curr Opin Chem Biol 2019; 52:157-167. [DOI: 10.1016/j.cbpa.2019.07.008] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2019] [Revised: 06/27/2019] [Accepted: 07/18/2019] [Indexed: 02/02/2023]
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7
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Liu Y, Xu LP, Wang Q, Yang B, Zhang X. Synergistic Inhibitory Effect of GQDs-Tramiprosate Covalent Binding on Amyloid Aggregation. ACS Chem Neurosci 2018; 9:817-823. [PMID: 29244487 DOI: 10.1021/acschemneuro.7b00439] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Inhibiting the amyloid aggregation is considered to be an effective strategy to explore possible treatment of amyloid-related diseases including Alzheimer's disease, Parkinson's disease, and type II diabetes. Herein, a new high-efficiency and low-cytotoxicity Aβ aggregation inhibitors, GQD-T, was designed through the combination of two Aβ aggregation inhibitors, graphene quantum dots (GQDs) and tramiprosate. GQD-T showed the capability of efficiently inhibiting the aggregation of Aβ peptides and rescuing Aβ-induced cytotoxicity due to the synergistic effect of the GQDs and tramiprosate. In addition, the GQD-T has the characteristics of low toxicity and great biocompatibility. It is believed that GQD-T may be a potential candidate for an Alzheimer's drug and this work provides a new strategy for exploring Aβ peptide aggregation inhibitors.
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Affiliation(s)
- Yibiao Liu
- Institute of Nanostructured Functional Materials, Huanghe Science & Technology College, Zhengzhou 450006, P.R. China
- Henan Provincial Key Laboratory of Nano-composite Materials and Applications, Huanghe Science & Technology College, Zhengzhou 450006, P.R. China
| | - Li-Ping Xu
- Research Center for Bioengineering and Sensing Technology, University of Science & Technology Beijing, Beijing 100083, P.R. China
| | - Qiang Wang
- State Key Laboratory of Coal Conversion, Institute of Coal Chemistry, The Chinese Academy of Sciences, Taiyuan 030001, P.R. China
| | - Baocheng Yang
- Institute of Nanostructured Functional Materials, Huanghe Science & Technology College, Zhengzhou 450006, P.R. China
- Henan Provincial Key Laboratory of Nano-composite Materials and Applications, Huanghe Science & Technology College, Zhengzhou 450006, P.R. China
| | - Xueji Zhang
- Research Center for Bioengineering and Sensing Technology, University of Science & Technology Beijing, Beijing 100083, P.R. China
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8
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Zhang H, Dong X, Liu F, Zheng J, Sun Y. Ac-LVFFARK-NH 2 conjugation to β-cyclodextrin exhibits significantly enhanced performance on inhibiting amyloid β-protein fibrillogenesis and cytotoxicity. Biophys Chem 2018; 235:40-47. [DOI: 10.1016/j.bpc.2018.02.002] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2017] [Revised: 01/12/2018] [Accepted: 02/04/2018] [Indexed: 11/16/2022]
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9
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Stark T, Lieblein T, Pohland M, Kalden E, Freund P, Zangl R, Grewal R, Heilemann M, Eckert GP, Morgner N, Göbel MW. Peptidomimetics That Inhibit and Partially Reverse the Aggregation of Aβ1–42. Biochemistry 2017; 56:4840-4849. [DOI: 10.1021/acs.biochem.7b00223] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
| | | | | | | | | | | | - Rekha Grewal
- Institute
of Nutritional Sciences, Justus-Liebig-University Giessen, Wilhelmstrasse
20, D-35392 Giessen, Germany
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10
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Ahmad I, Mozhi A, Yang L, Han Q, Liang X, Li C, Yang R, Wang C. Graphene oxide-iron oxide nanocomposite as an inhibitor of Aβ 42 amyloid peptide aggregation. Colloids Surf B Biointerfaces 2017; 159:540-545. [PMID: 28846964 DOI: 10.1016/j.colsurfb.2017.08.020] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2017] [Revised: 08/03/2017] [Accepted: 08/13/2017] [Indexed: 10/19/2022]
Abstract
Inhibiting amyloid β (Aβ) aggregation has drawn much attention because it is one of the main reasons for the cause of Alzheimer's disease (AD). Here we have synthesized a nanocomposite of graphene oxide-iron oxide (GOIO) and demonstrated its ability of modulating Aβ aggregation. The inhibition effects of the GOIO nanocomposite on Aβ aggregates was studied by Thioflavin T fluorescence assay, circular dichroism and transmission electron microscopy, respectively. Furthermore, the cell viability study revealed that the GOIO nanocomposite can reduce the toxicity of Aβ fibrils to neuroblastoma cells. Our results demonstrated that the combination of GO and IO as a nanocomposite material has a potential use for the design new therapeutic agents for the treatment of Alzheimer's disease.
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Affiliation(s)
- Israr Ahmad
- CAS Key Lab for Biomedical Effects of Nanomaterials and Nanosafety, CAS center for Excellence in Nanoscience, National Center for Nanoscience and Technology, University of Chinese Academy of Sciences, Beijing, 100190, PR China
| | - Anbu Mozhi
- CAS Key Lab for Biomedical Effects of Nanomaterials and Nanosafety, CAS center for Excellence in Nanoscience, National Center for Nanoscience and Technology, University of Chinese Academy of Sciences, Beijing, 100190, PR China
| | - Lin Yang
- CAS Key Lab for Biomedical Effects of Nanomaterials and Nanosafety, CAS center for Excellence in Nanoscience, National Center for Nanoscience and Technology, University of Chinese Academy of Sciences, Beijing, 100190, PR China
| | - Qiusen Han
- CAS Key Lab for Biomedical Effects of Nanomaterials and Nanosafety, CAS center for Excellence in Nanoscience, National Center for Nanoscience and Technology, University of Chinese Academy of Sciences, Beijing, 100190, PR China; Sino-Danish College, University of Chinese Academy of Sciences, Beijing, 100190, PR China
| | - Xingjie Liang
- CAS Key Lab for Biomedical Effects of Nanomaterials and Nanosafety, CAS center for Excellence in Nanoscience, National Center for Nanoscience and Technology, University of Chinese Academy of Sciences, Beijing, 100190, PR China
| | - Chan Li
- CAS Key Lab for Biomedical Effects of Nanomaterials and Nanosafety, CAS center for Excellence in Nanoscience, National Center for Nanoscience and Technology, University of Chinese Academy of Sciences, Beijing, 100190, PR China
| | - Rong Yang
- CAS Key Lab for Biomedical Effects of Nanomaterials and Nanosafety, CAS center for Excellence in Nanoscience, National Center for Nanoscience and Technology, University of Chinese Academy of Sciences, Beijing, 100190, PR China; Sino-Danish College, University of Chinese Academy of Sciences, Beijing, 100190, PR China.
| | - Chen Wang
- CAS Key Lab for Biomedical Effects of Nanomaterials and Nanosafety, CAS center for Excellence in Nanoscience, National Center for Nanoscience and Technology, University of Chinese Academy of Sciences, Beijing, 100190, PR China.
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11
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Inhibition of amyloid oligomerization into different supramolecular architectures by small molecules: mechanistic insights and design rules. Future Med Chem 2017; 9:797-810. [DOI: 10.4155/fmc-2017-0026] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Protein misfolding and aggregation have been associated with several human disorders, including Alzheimer’s, Parkinson’s and Huntington’s diseases, as well as senile systemic amyloidosis and Type II diabetes. However, there is no current disease-modifying therapy available for the treatment of these disorders. In spite of extensive academic, pharmaceutical, medicinal and clinical research, a complete mechanistic model for this family of diseases is still lacking. In this review, we primarily discuss the different types of small molecular entities which have been used for the inhibition of the aggregation process of different amyloidogenic proteins under diseased conditions. These include small peptides, polyphenols, inositols, quinones and their derivatives, and metal chelator molecules. In recent years, these groups of molecules have been extensively studied using in vitro, in vivo and computational models to understand their mechanism of action and common structural features underlying the process of inhibition. A salient feature found to be instrumental in the process of inhibition is the balance between the aromatic unit that functions as the amyloid recognition unit and the hydrophilic amyloid breaker unit. The establishment of structure–function relationship for amyloid-modifying therapies by the various functional entities should serve as an important step toward the development of efficient therapeutics.
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12
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Karnes MA, Schettler SL, Werner HM, Kurz AF, Horne WS, Lengyel GA. Thermodynamic and Structural Impact of α,α-Dialkylated Residue Incorporation in a β-Hairpin Peptide. Org Lett 2016; 18:3902-5. [PMID: 27436716 DOI: 10.1021/acs.orglett.6b01936] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Peptides containing α,α-dialkylated α-amino acids, owing to their ability to disrupt aggregation of β-amyloid proteins, have therapeutic potential in the treatment of neurodegenerative diseases. Thermodynamic and structural analyses are reported for a series of β-hairpin peptides containing α,α-dialkylated α-amino acids with varying side-chain lengths. The results of these experiments show that α,α-dialkylated α-amino acids with side-chain lengths longer than one carbon unit are tolerated in a β-hairpin, although at a moderate cost to folded stability.
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Affiliation(s)
- Megan A Karnes
- Department of Chemistry, Slippery Rock University , Slippery Rock, Pennsylvania 16057, United States
| | - Shelby L Schettler
- Department of Chemistry, Slippery Rock University , Slippery Rock, Pennsylvania 16057, United States
| | - Halina M Werner
- Department of Chemistry, University of Pittsburgh , Pittsburgh, Pennsylvania 15260, United States
| | - Alana F Kurz
- Department of Chemistry, University of Pittsburgh , Pittsburgh, Pennsylvania 15260, United States
| | - W Seth Horne
- Department of Chemistry, University of Pittsburgh , Pittsburgh, Pennsylvania 15260, United States
| | - George A Lengyel
- Department of Chemistry, Slippery Rock University , Slippery Rock, Pennsylvania 16057, United States
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13
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Kim Y, Park JH, Lee H, Nam JM. How Do the Size, Charge and Shape of Nanoparticles Affect Amyloid β Aggregation on Brain Lipid Bilayer? Sci Rep 2016; 6:19548. [PMID: 26782664 PMCID: PMC4726094 DOI: 10.1038/srep19548] [Citation(s) in RCA: 74] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2015] [Accepted: 11/13/2015] [Indexed: 11/21/2022] Open
Abstract
Here, we studied the effect of the size, shape, and surface charge of Au nanoparticles (AuNPs) on amyloid beta (Aβ) aggregation on a total brain lipid-based supported lipid bilayer (brain SLB), a fluid platform that facilitates Aβ-AuNP aggregation process. We found that larger AuNPs induce large and amorphous aggregates on the brain SLB, whereas smaller AuNPs induce protofibrillar Aβ structures. Positively charged AuNPs were more strongly attracted to Aβ than negatively charged AuNPs, and the stronger interactions between AuNPs and Aβ resulted in fewer β-sheets and more random coil structures. We also compared spherical AuNPs, gold nanorods (AuNRs), and gold nanocubes (AuNCs) to study the effect of nanoparticle shape on Aβ aggregation on the brain SLB. Aβ was preferentially bound to the long axis of AuNRs and fewer fibrils were formed whereas all the facets of AuNCs interacted with Aβ to produce the fibril networks. Finally, it was revealed that different nanostructures induce different cytotoxicity on neuroblastoma cells, and, overall, smaller Aβ aggregates induce higher cytotoxicity. The results offer insight into the roles of NPs and brain SLB in Aβ aggregation on the cell membrane and can facilitate the understanding of Aβ-nanostructure co-aggregation mechanism and tuning Aβ aggregate structures.
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Affiliation(s)
- Yuna Kim
- Department of Chemistry, Seoul National University, 599 Gwanak-ro, Gwanak-gu, Seoul 151-742, South Korea
| | - Ji-Hyun Park
- Department of Chemistry, Seoul National University, 599 Gwanak-ro, Gwanak-gu, Seoul 151-742, South Korea
| | - Hyojin Lee
- Department of Chemistry, Seoul National University, 599 Gwanak-ro, Gwanak-gu, Seoul 151-742, South Korea
| | - Jwa-Min Nam
- Department of Chemistry, Seoul National University, 599 Gwanak-ro, Gwanak-gu, Seoul 151-742, South Korea
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Liu Y, Xu LP, Dai W, Dong H, Wen Y, Zhang X. Graphene quantum dots for the inhibition of β amyloid aggregation. NANOSCALE 2015; 7:19060-5. [PMID: 26515666 DOI: 10.1039/c5nr06282a] [Citation(s) in RCA: 92] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
The aggregation of Aβ peptides is a crucial factor leading to Alzheimer's disease (AD). Inhibiting the Aβ peptide aggregation has become one of the most essential strategies to treat AD. In this work, efficient and low-cytotoxicity inhibitors, graphene quantum dots (GQDs) are reported for their application in inhibiting the aggregation of Aβ peptides. Compared to other carbon materials, the low cytotoxicity and great biocompatibility of GQDs give an advantage to the clinical research for AD. In addition, the GQDs may cross the blood-brain barrier (BBB) because of the small size. It is believed that GQDs may be therapeutic agents against AD. This work provides a novel insight into the development of Alzheimer's drugs.
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Affiliation(s)
- Yibiao Liu
- Research Center for Bioengineering and Sensing Technology, University of Science & Technology Beijing, Beijing 100083, P.R. China.
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15
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Cabrele C, Martinek TA, Reiser O, Berlicki Ł. Peptides Containing β-Amino Acid Patterns: Challenges and Successes in Medicinal Chemistry. J Med Chem 2014; 57:9718-39. [DOI: 10.1021/jm5010896] [Citation(s) in RCA: 182] [Impact Index Per Article: 18.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Chiara Cabrele
- Department
of Molecular Biology, University of Salzburg, Billrothstrasse 11, 5020 Salzburg, Austria
| | - Tamás A. Martinek
- SZTE-MTA
Lendulet Foldamer Research Group, Institute of Pharmaceutical Analysis, University of Szeged, Somogyi u. 6., H-6720 Szeged, Hungary
| | - Oliver Reiser
- Institute
of Organic Chemistry, University of Regensburg, Universitätsstrasse 31, 93053 Regensburg, Germany
| | - Łukasz Berlicki
- Department
of Bioorganic Chemistry, Faculty of Chemistry, Wrocław University of Technology, Wybrzeże Wyspiańskiego 27, 50-370 Wrocław, Poland
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16
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Polyphenols as therapeutic molecules in Alzheimer's disease through modulating amyloid pathways. Mol Neurobiol 2014; 51:466-79. [PMID: 24826916 DOI: 10.1007/s12035-014-8722-9] [Citation(s) in RCA: 77] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2014] [Accepted: 04/17/2014] [Indexed: 02/07/2023]
Abstract
Alzheimer's disease (AD) is a complex and multifactorial neurodegenerative condition. The complex pathology of this disease includes oxidative stress, metal deposition, formation of aggregates of amyloid and tau, enhanced immune responses, and disturbances in cholinesterase. Drugs targeted toward reduction of amyloidal load have been discovered, but there is no effective pharmacological treatment for combating the disease so far. Natural products have become an important avenue for drug discovery research. Polyphenols are natural products that have been shown to be effective in the modulation of the type of neurodegenerative changes seen in AD, suggesting a possible therapeutic role. The present review focuses on the chemistry of polyphenols and their role in modulating amyloid precursor protein (APP) processing. We also provide new hypotheses on how these therapeutic molecules may modulate APP processing, prevent Aβ aggregation, and favor disruption of preformed fibrils. Finally, the role of polyphenols in modulating Alzheimer's pathology is discussed.
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17
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Bhattacharjee P, Bhattacharyya D. Factor V activator from Daboia russelli russelli venom destabilizes β-amyloid aggregate, the hallmark of Alzheimer disease. J Biol Chem 2013; 288:30559-30570. [PMID: 23986449 DOI: 10.1074/jbc.m113.511410] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Formation of plaque by fibrils of β-amyloid (Aβ) peptide in the brain is the characteristic feature of Alzheimer disease (AD). Inhibition of the process of aggregate formation from Aβ-monomer and destabilization of the aggregate could be useful for prevention and propagation of the disease respectively. Russell's viper venom (RVV) contains protein(s) that destabilize Aβ aggregates as revealed from the thioflavin T assay. The active component was identified as factor V activator (RVV-V). Among the possible mechanisms of destabilization, RVV-V-mediated proteolysis was ruled out from mass spectrometric data and the thioflavin T assay. The alternate hypothesis that small peptides derived from RVV-V destabilize the aggregate is better supported by experimental results. Six small peptides were synthesized using RVV-V as the template, and three unrelated peptides were synthesized to serve as controls. Destabilization of Aβ aggregate by these peptides was studied using spectrofluorometric assays, atomic force microscopy, transmission electron microscopy, and confocal microscopy. Among the peptides, CTNIF and the mixture of the six peptides were most potent in converting the aggregates to the monomeric state and thus, preventing cytotoxicity in SH-SY5Y human neuroblastoma cells. The control peptides failed to show similar effects. Moreover, some of these peptides are stable in blood for 24 h. Therefore, these venom-derived peptides offer an encouraging opportunity to prevent amyloidosis and may provide information to combat AD.
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Affiliation(s)
- Payel Bhattacharjee
- From the Division of Structural Biology and Bioinformatics, Council of Scientific and Industrial Research, Indian Institute of Chemical Biology, Jadavpur, Kolkata 700032, India.
| | - Debasish Bhattacharyya
- From the Division of Structural Biology and Bioinformatics, Council of Scientific and Industrial Research, Indian Institute of Chemical Biology, Jadavpur, Kolkata 700032, India.
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18
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Mahmoudi M, Kalhor HR, Laurent S, Lynch I. Protein fibrillation and nanoparticle interactions: opportunities and challenges. NANOSCALE 2013; 5:2570-88. [PMID: 23463168 DOI: 10.1039/c3nr33193h] [Citation(s) in RCA: 128] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
Due to their ultra-small size, nanoparticles (NPs) have distinct properties compared with the bulk form of the same materials. These properties are rapidly revolutionizing many areas of medicine and technology. NPs are recognized as promising and powerful tools to fight against the human brain diseases such as multiple sclerosis or Alzheimer's disease. In this review, after an introductory part on the nature of protein fibrillation and the existing approaches for its investigations, the effects of NPs on the fibrillation process have been considered. More specifically, the role of biophysicochemical properties of NPs, which define their affinity for protein monomers, unfolded monomers, oligomers, critical nuclei, and other prefibrillar states, together with their influence on protein fibrillation kinetics has been described in detail. In addition, current and possible-future strategies for controlling the desired effect of NPs and their corresponding effects on the conformational changes of the proteins, which have significant roles in the fibrillation process, have been presented.
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Affiliation(s)
- Morteza Mahmoudi
- Department of Nanotechnology, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran.
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19
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Mahmoudi M, Quinlan-Pluck F, Monopoli MP, Sheibani S, Vali H, Dawson KA, Lynch I. Influence of the physiochemical properties of superparamagnetic iron oxide nanoparticles on amyloid β protein fibrillation in solution. ACS Chem Neurosci 2013; 4:475-85. [PMID: 23509983 DOI: 10.1021/cn300196n] [Citation(s) in RCA: 96] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Superparamagnetic iron oxide nanoparticles (SPIONs) are recognized as promising nanodiagnostic materials due to their biocompatibility, unique magnetic properties, and their application as multimodal contrast agents. As coated SPIONs have potential use in the diagnosis and treatment of various brain diseases such as Alzheimer's, a comprehensive understanding of their interactions with Aβ and other amyloidogenic proteins is essential prior to their clinical application. Here we demonstrate the effect of thickness and surface charge of the coating layer of SPIONs on the kinetics of fibrillation of Aβ in aqueous solution. A size and surface area dependent "dual" effect on Aβ fibrillation was observed. While lower concentrations of SPIONs inhibited fibrillation, higher concentrations increased the rate of Aβ fibrillation. With respect to coating charge, it is evident that the positively charged SPIONs are capable of promoting fibrillation at significantly lower particle concentrations compared with negatively charged or uncharged SPIONs. This suggests that in addition to the presence of particles, which affect the concentration of monomeric protein in solution (and thereby the nucleation time), there are also effects of binding on the protein conformation.
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Affiliation(s)
| | - Fiona Quinlan-Pluck
- Centre for BioNano Interactions, School of Chemistry and Chemical Biology, & Conway Institute of Biomolecular and Biomedical Sciences University College Dublin, Belfield, Dublin 4, Ireland
| | - Marco P. Monopoli
- Centre for BioNano Interactions, School of Chemistry and Chemical Biology, & Conway Institute of Biomolecular and Biomedical Sciences University College Dublin, Belfield, Dublin 4, Ireland
| | - Sara Sheibani
- Department of Chemistry and
Chemical Engineering, Royal Military College, Kingston, Ontario K7K 7B4, Canada
| | - Hojatollah Vali
- Department of Anatomy and Cell Biology, McGill University, Montreal, Canada
| | - Kenneth A. Dawson
- Centre for BioNano Interactions, School of Chemistry and Chemical Biology, & Conway Institute of Biomolecular and Biomedical Sciences University College Dublin, Belfield, Dublin 4, Ireland
| | - Iseult Lynch
- Centre for BioNano Interactions, School of Chemistry and Chemical Biology, & Conway Institute of Biomolecular and Biomedical Sciences University College Dublin, Belfield, Dublin 4, Ireland
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Ferrocene tripeptide Gly-Pro-Arg conjugates: Synthesis and inhibitory effects on Alzheimer’s Aβ1–42 fibrillogenesis and Aβ-induced cytotoxicity in vitro. Bioorg Med Chem 2013; 21:395-402. [DOI: 10.1016/j.bmc.2012.11.030] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2012] [Revised: 11/21/2012] [Accepted: 11/22/2012] [Indexed: 11/19/2022]
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21
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Kinetic studies of inhibition of the amyloid beta (1-42) aggregation using a ferrocene-tagged β-sheet breaker peptide. Anal Biochem 2012; 434:292-9. [PMID: 23232068 DOI: 10.1016/j.ab.2012.11.025] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2012] [Revised: 11/16/2012] [Accepted: 11/26/2012] [Indexed: 01/01/2023]
Abstract
The aggregation of amyloidogenic proteins/peptides has been closely linked to the neuropathology of several important neurological disorders. In Alzheimer's disease, amyloid beta (Aβ) peptides and their aggregation are believed to be at least partially responsible for the etiology of Alzheimer's disease. The aggregate-inflicted cellular toxicity can be inhibited by short peptides whose sequences are homologous to segments of the Aβ(1-42) peptide responsible for β-sheet stacking (referred to as the β-sheet breaker peptides). Here, a water-soluble ferrocene (Fc)-tagged β-sheet breaker peptide, Fc-KLVFFK(6), was used as an electrochemical probe for kinetic studies of the inhibition of the Aβ(1-42) fibrillation process and for determination of the optimal concentration of β-sheet breaker peptide for efficient inhibition. Our results demonstrate that Fc-KLVFFK(6) interacts with the Aβ aggregates instantaneously in solution, and a sub-stoichiometric amount of Fc-KLVFFK(6) is sufficient to inhibit the formation of the Aβ oligomers and fibrils and to reduce the toxicity of Aβ(1-42). The interaction between Fc-KLVFFK(6) and Aβ(1-42) follows a pseudo-first-order reaction, with a rate constant of 1.89 ± 0.05 × 10(-4) s(-1). Tagging β-sheet breaker peptides with a redox label facilitates design, screening, and rational use of peptidic inhibitors for impeding/altering Aβ aggregation.
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Fülöp L, Mándity IM, Juhász G, Szegedi V, Hetényi A, Wéber E, Bozsó Z, Simon D, Benkő M, Király Z, Martinek TA. A foldamer-dendrimer conjugate neutralizes synaptotoxic β-amyloid oligomers. PLoS One 2012; 7:e39485. [PMID: 22859942 PMCID: PMC3408453 DOI: 10.1371/journal.pone.0039485] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2012] [Accepted: 05/21/2012] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND AND AIMS Unnatural self-organizing biomimetic polymers (foldamers) emerged as promising materials for biomolecule recognition and inhibition. Our goal was to construct multivalent foldamer-dendrimer conjugates which wrap the synaptotoxic β-amyloid (Aβ) oligomers with high affinity through their helical foldamer tentacles. Oligomeric Aβ species play pivotal role in Alzheimer's disease, therefore recognition and direct inhibition of this undruggable target is a great current challenge. METHODS AND RESULTS Short helical β-peptide foldamers with designed secondary structures and side chain chemistry patterns were applied as potential recognition segments and their binding to the target was tested with NMR methods (saturation transfer difference and transferred-nuclear Overhauser effect). Helices exhibiting binding in the µM region were coupled to a tetravalent G0-PAMAM dendrimer. In vitro biophysical (isothermal titration calorimetry, dynamic light scattering, transmission electron microscopy and size-exclusion chromatography) and biochemical tests (ELISA and dot blot) indicated the tight binding between the foldamer conjugates and the Aβ oligomers. Moreover, a selective low nM interaction with the low molecular weight fraction of the Aβ oligomers was found. Ex vivo electrophysiological experiments revealed that the new material rescues the long-term potentiation from the toxic Aβ oligomers in mouse hippocampal slices at submicromolar concentration. CONCLUSIONS The combination of the foldamer methodology, the fragment-based approach and the multivalent design offers a pathway to unnatural protein mimetics that are capable of specific molecular recognition, and has already resulted in an inhibitor for an extremely difficult target.
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Affiliation(s)
- Lívia Fülöp
- Department of Medical Chemistry, University of Szeged, Szeged, Hungary
| | - István M. Mándity
- Institute of Pharmaceutical Chemistry, University of Szeged, Szeged, Hungary
| | - Gábor Juhász
- Department of Medical Chemistry, University of Szeged, Szeged, Hungary
| | - Viktor Szegedi
- Bay Zoltán Foundation for Applied Research – BAYGEN, Szeged, Hungary
| | | | - Edit Wéber
- Institute of Pharmaceutical Chemistry, University of Szeged, Szeged, Hungary
| | - Zsolt Bozsó
- Department of Medical Chemistry, University of Szeged, Szeged, Hungary
| | - Dóra Simon
- Department of Medical Chemistry, University of Szeged, Szeged, Hungary
| | - Mária Benkő
- Department of Physical Chemistry and Materials Science, University of Szeged, Szeged, Hungary
| | - Zoltán Király
- Department of Physical Chemistry and Materials Science, University of Szeged, Szeged, Hungary
| | - Tamás A. Martinek
- Institute of Pharmaceutical Chemistry, University of Szeged, Szeged, Hungary
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23
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Wang C, Yang A, Li X, Li D, Zhang M, Du H, Li C, Guo Y, Mao X, Dong M, Besenbacher F, Yang Y, Wang C. Observation of molecular inhibition and binding structures of amyloid peptides. NANOSCALE 2012; 4:1895-909. [PMID: 22334382 DOI: 10.1039/c2nr11508e] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Unveiling interactions between labeling molecules and amyloid fibrils is essential to develop new detection methods for studying amyloid structures under various conditions. This review endeavours to reflect the progress in studying interactions between molecular inhibitors and amyloid peptides using a series of experimental approaches, such as X-ray diffraction, nuclear magnetic resonance, scanning probe microscopy, and electron microscopy. The revealed binding mechanisms of anti-amyloid drugs and target proteins could benefit the rational design of drugs for prevention or treatment of amyloidal diseases.
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Affiliation(s)
- Chenxuan Wang
- National Center for Nanoscience and Technology, Beijing, 100190, PR China
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Sakono M, Zako T, Yohda M, Maeda M. Amyloid oligomer detection by immobilized molecular chaperone. Biochem Eng J 2012. [DOI: 10.1016/j.bej.2011.12.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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25
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Synthesis and evaluation of ferrocenoyl pentapeptide (Fc-KLVFF) as an inhibitor of Alzheimer's Aβ₁-₄₂ fibril formation in vitro. Bioorg Med Chem Lett 2011; 21:5818-21. [PMID: 21855336 DOI: 10.1016/j.bmcl.2011.07.111] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2011] [Revised: 07/14/2011] [Accepted: 07/28/2011] [Indexed: 11/22/2022]
Abstract
Aggregation and fibril formation of β-amyloid peptides (Aβ) is the key event in the pathogenesis of Alzheimer's disease. Many efforts have been made on the development of effective inhibitors to prevent Aβ fibril formation or disassemble the preformed Aβ fibrils. Peptide inhibitors with sequences homologous to the hydrophobic segments of Aβ can alter the aggregation pathway of Aβ, together with decrease of the cell toxicity. In this study, the conjugate of ferrocenoyl (Fc) with pentapeptide KLVFF (Fc-KLVFF), was synthesized by HBTU/HOBt protocol in solution. The inhibitory effect of Fc-KLVFF on Aβ(1-42) fibril formation was evaluated by thioflavin T fluorescence assay, and confirmed by atomic force microscopy (AFM) and transmission electron microscopy (TEM) analyses. Fc-KLVFF shows high inhibitory effect towards the fibril formation of Aβ(1-42). Additionally, the attachment of ferrocenoyl moiety onto peptides allows us to investigate the interaction between the inhibitor and Aβ(1-42) in real-time by electrochemical method. As expected, tethering of ferrocenoyl moiety onto pentapeptide shows improved lipophilicity and significant resistance towards proteolytic degradation compared to its parent peptide.
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26
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Sood A, Abid M, Sauer C, Hailemichael S, Foster M, Török B, Török M. Disassembly of preformed amyloid beta fibrils by small organofluorine molecules. Bioorg Med Chem Lett 2011; 21:2044-7. [PMID: 21354796 DOI: 10.1016/j.bmcl.2011.02.012] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2010] [Revised: 02/02/2011] [Accepted: 02/03/2011] [Indexed: 12/30/2022]
Abstract
A potential therapeutic approach for Alzheimer's disease is to reduce the amount of toxic amyloid-beta oligomers and fibrillar amyloid plaques. In order to contribute to this approach the ability of small organofluorine compounds that were previously reported as successful inhibitors of fibrillogenesis to destabilize preformed fibrils of the amyloid-beta peptide was studied. These organofluorine molecules including chiral compounds were tested in vitro using standard methods based on Thioflavin-T (THT) fluorescence spectroscopy, atomic force microscopy (AFM) and Fourier-transform infrared spectroscopy (FTIR). It was observed that 5'-halogen substituted 3,3,3-trifluoromethyl-2-hydroxyl-(indol-3-yl)-propionic acid esters showed significant activity in the disassembly of the preformed fibrils. Since the same compounds were identified as strong fibrillogenesis inhibitors as well, this dual action makes them promising candidates for further drug development.
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Affiliation(s)
- Abha Sood
- Department of Chemistry, University of Massachusetts Boston, 100 Morrissey Blvd., Boston, MA 02125-3393, USA
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27
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Zheng J, Liu C, Sawaya MR, Vadla B, Khan S, Woods RJ, Eisenberg D, Goux WJ, Nowick JS. Macrocyclic β-sheet peptides that inhibit the aggregation of a tau-protein-derived hexapeptide. J Am Chem Soc 2011; 133:3144-57. [PMID: 21319744 PMCID: PMC3048834 DOI: 10.1021/ja110545h] [Citation(s) in RCA: 105] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
This paper describes studies of a series of macrocyclic β-sheet peptides 1 that inhibit the aggregation of a tau-protein-derived peptide. The macrocyclic β-sheet peptides comprise a pentapeptide "upper" strand, two δ-linked ornithine turn units, and a "lower" strand comprising two additional residues and the β-sheet peptidomimetic template "Hao". The tau-derived peptide Ac-VQIVYK-NH(2) (AcPHF6) aggregates in solution through β-sheet interactions to form straight and twisted filaments similar to those formed by tau protein in Alzheimer's neurofibrillary tangles. Macrocycles 1 containing the pentapeptide VQIVY in the "upper" strand delay and suppress the onset of aggregation of the AcPHF6 peptide. Inhibition is particularly pronounced in macrocycles 1a, 1d, and 1f, in which the two residues in the "lower" strand provide a pattern of hydrophobicity and hydrophilicity that matches that of the pentapeptide "upper" strand. Inhibition varies strongly with the concentration of these macrocycles, suggesting that it is cooperative. Macrocycle 1b containing the pentapeptide QIVYK shows little inhibition, suggesting the possibility of a preferred direction of growth of AcPHF6 β-sheets. On the basis of these studies, a model is proposed in which the AcPHF6 amyloid grows as a layered pair of β-sheets and in which growth is blocked by a pair of macrocycles that cap the growing paired hydrogen-bonding edges. This model provides a provocative and appealing target for future inhibitor design.
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Affiliation(s)
- Jing Zheng
- Department of Chemistry, University of California, Irvine, Irvine, California 92697-2025, USA
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28
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Bett CK, Serem WK, Fontenot KR, Hammer RP, Garno JC. Effects of peptides derived from terminal modifications of the aβ central hydrophobic core on aβ fibrillization. ACS Chem Neurosci 2010; 1:661-78. [PMID: 22778807 DOI: 10.1021/cn900019r] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2009] [Accepted: 08/05/2010] [Indexed: 01/06/2023] Open
Abstract
Considerable research effort has focused on the discovery of mitigators that block the toxicity of the β-amyloid peptide (Aβ) by targeting a specific step involved in Aβ fibrillogenesis and subsequent aggregation. Given that aggregation intermediates are hypothesized to be responsible for Aβ toxicity, such compounds could likely prevent or mitigate aggregation, or alternatively cause further association of toxic oligomers into larger nontoxic aggregates. Herein we investigate the effect of modifications of the KLVFF hydrophobic core of Aβ by replacing N- and C-terminal groups with various polar moieties. Several of these terminal modifications were found to disrupt the formation of amyloid fibrils and in some cases induced the disassembly of preformed fibrils. Significantly, mitigators that incorporate MiniPEG polar groups were found to be effective against Aβ(1-40) fibrilligonesis. Previously, we have shown that mitigators incorporating alpha,alpha-disubstituted amino acids (ααAAs) were effective in disrupting fibril formation as well as inducing fibril disassembly. In this work, we further disclose that the number of polar residues (six) and ααAAs (three) in the original mitigator can be reduced without dramatically changing the ability to disrupt Aβ(1-40) fibrillization in vitro.
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Affiliation(s)
- Cyrus K. Bett
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803
| | - Wilson K. Serem
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803
| | - Krystal R. Fontenot
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803
| | - Robert P. Hammer
- New England Peptide LLC, 65 Zub Lane, Gardner, Massachusetts 01440
| | - Jayne C. Garno
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803
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