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Al-Shabib NA, Khan JM, Malik A, Alamri A, Rehman MT, AlAjmi MF, Husain FM. Probing the interaction mechanisms between sunset yellow dye and trypsin protein leading to amorphous aggregation under low pH conditions. Int J Biol Macromol 2024; 265:130442. [PMID: 38417745 DOI: 10.1016/j.ijbiomac.2024.130442] [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: 12/10/2023] [Revised: 02/20/2024] [Accepted: 02/23/2024] [Indexed: 03/01/2024]
Abstract
Protein aggregation poses a significant concern in the field of food sciences, and various factors, such as synthetic food dyes, can contribute to protein aggregation. One such dye, Sunset Yellow (SY), is commonly employed in the food industry. Trypsin was used as a model protein to assess the impact of SY. We employed several biophysical techniques to examine the binding and aggregation mechanisms between SY and trypsin at different pHs. Results from intrinsic fluorescence measurements indicate a stronger interaction between SY and trypsin at pH 2.0 compared to pH 6.0. Turbidity data reveal trypsin aggregation in the presence of 0.05-3.0 mM SY at pH 2.0, while no aggregation was observed at pH 6.0. Kinetic data demonstrate a rapid, lag-phase-free SY-induced aggregation of trypsin. Circular dichroism analysis reveals that trypsin adopts a secondary structure in the presence of SY at pH 6.0, whereas at pH 2.0, the secondary structure was nearly lost with increasing SY concentrations. Furthermore, turbidity and kinetics data suggest that trypsin aggregation depends on trypsin concentrations and pH. Our study highlights potential health risks associated with the consumption of SY, providing insights into its impact on human health and emphasizing the necessity for further research in this field.
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Affiliation(s)
- Nasser Abdulatif Al-Shabib
- Department of Food Science and Nutrition, College of Food and Agricultural Sciences, King Saud University, Riyadh 11451, Saudi Arabia
| | - Javed Masood Khan
- Department of Food Science and Nutrition, College of Food and Agricultural Sciences, King Saud University, Riyadh 11451, Saudi Arabia.
| | - Ajamaluddin Malik
- Department of Biochemistry, College of Science, King Saud University, Riyadh, Saudi Arabia
| | - Abdulaziz Alamri
- Department of Biochemistry, College of Science, King Saud University, Riyadh, Saudi Arabia
| | - Md Tabish Rehman
- King Saud University, Department of Pharmacognosy, College of Pharmacy, Riyadh 11451, Saudi Arabia
| | - Mohamed F AlAjmi
- King Saud University, Department of Pharmacognosy, College of Pharmacy, Riyadh 11451, Saudi Arabia
| | - Fohad Mabood Husain
- Department of Food Science and Nutrition, College of Food and Agricultural Sciences, King Saud University, Riyadh 11451, Saudi Arabia
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2
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Saenger T, Schulte MF, Vordenbäumen S, Hermann FC, Bertelsbeck J, Meier K, Bleck E, Schneider M, Jose J. Structural Analysis of Breast-Milk α S1-Casein: An α-Helical Conformation Is Required for TLR4-Stimulation. Int J Mol Sci 2024; 25:1743. [PMID: 38339021 PMCID: PMC10855866 DOI: 10.3390/ijms25031743] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2023] [Revised: 01/19/2024] [Accepted: 01/21/2024] [Indexed: 02/12/2024] Open
Abstract
Breast-milk αS1-casein is a Toll-like receptor 4 (TLR4) agonist, whereas phosphorylated αS1-casein does not bind TLR4. The objective of this study was to analyse the structural requirements for these effects. In silico analysis of αS1-casein indicated high α-helical content with coiled-coil characteristics. This was confirmed by CD-spectroscopy, showing the α-helical conformation to be stable between pH 2 and 7.4. After in vitro phosphorylation, the α-helical content was significantly reduced, similar to what it was after incubation at 80 °C. This conformation showed no in vitro induction of IL-8 secretion via TLR4. A synthetic peptide corresponding to V77-E92 of αS1-casein induced an IL-8 secretion of 0.95 ng/mL via TLR4. Our results indicate that αS1-casein appears in two distinct conformations, an α-helical TLR4-agonistic and a less α-helical TLR4 non-agonistic conformation induced by phosphorylation. This is to indicate that the immunomodulatory role of αS1-casein, as described before, could be regulated by conformational changes induced by phosphorylation.
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Affiliation(s)
- Thorsten Saenger
- Institute for Pharmaceutical and Medicinal Chemistry, University of Münster, PharmaCampus, Correnstr. 48, 48149 Münster, Germany; (T.S.); (M.F.S.)
| | - Marten F. Schulte
- Institute for Pharmaceutical and Medicinal Chemistry, University of Münster, PharmaCampus, Correnstr. 48, 48149 Münster, Germany; (T.S.); (M.F.S.)
| | - Stefan Vordenbäumen
- Department of Rheumatology and Hiller Research Unit Rheumatology, Medical Faculty, Heinrich-Heine-University Düsseldorf, Moorenstr. 5, 40225 Düsseldorf, Germany
| | - Fabian C. Hermann
- Institute for Pharmaceutical Biology and Phytochemie, University of Münster, PharmaCampus, Correnstr. 48, 48149 Münster, Germany
| | - Juliana Bertelsbeck
- Institute for Pharmaceutical and Medicinal Chemistry, University of Münster, PharmaCampus, Correnstr. 48, 48149 Münster, Germany; (T.S.); (M.F.S.)
| | - Kathrin Meier
- Institute for Pharmaceutical and Medicinal Chemistry, University of Münster, PharmaCampus, Correnstr. 48, 48149 Münster, Germany; (T.S.); (M.F.S.)
| | - Ellen Bleck
- Department of Rheumatology and Hiller Research Unit Rheumatology, Medical Faculty, Heinrich-Heine-University Düsseldorf, Moorenstr. 5, 40225 Düsseldorf, Germany
| | - Matthias Schneider
- Department of Rheumatology and Hiller Research Unit Rheumatology, Medical Faculty, Heinrich-Heine-University Düsseldorf, Moorenstr. 5, 40225 Düsseldorf, Germany
| | - Joachim Jose
- Institute for Pharmaceutical and Medicinal Chemistry, University of Münster, PharmaCampus, Correnstr. 48, 48149 Münster, Germany; (T.S.); (M.F.S.)
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3
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Paterna A, Santonicola P, Di Prima G, Rao E, Raccosta S, Zampi G, Russo C, Moran O, Manno M, Di Schiavi E, Librizzi F, Carrotta R. α S1-Casein-Loaded Proteo-liposomes as Potential Inhibitors in Amyloid Fibrillogenesis: In Vivo Effects on a C. elegans Model of Alzheimer's Disease. ACS Chem Neurosci 2023; 14:3894-3904. [PMID: 37847529 PMCID: PMC10623563 DOI: 10.1021/acschemneuro.3c00239] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2023] [Accepted: 09/18/2023] [Indexed: 10/18/2023] Open
Abstract
According to the amyloid hypothesis, in the early phases of Alzheimer's disease (AD), small soluble prefibrillar aggregates of the amyloid β-peptide (Aβ) interact with neuronal membranes, causing neural impairment. Such highly reactive and toxic species form spontaneously and transiently in the amyloid building pathway. A therapeutic strategy consists of the recruitment of these intermediates, thus preventing aberrant interaction with membrane components (lipids and receptors), which in turn may trigger a cascade of cellular disequilibria. Milk αs1-Casein is an intrinsically disordered protein that is able to inhibit Aβ amyloid aggregation in vitro, by sequestering transient species. In order to test αs1-Casein as an inhibitor for the treatment of AD, it needs to be delivered in the place of action. Here, we demonstrate the use of large unilamellar vesicles (LUVs) as suitable nanocarriers for αs1-Casein. Proteo-LUVs were prepared and characterized by different biophysical techniques, such as multiangle light scattering, atomic force imaging, and small-angle X-ray scattering; αs1-Casein loading was quantified by a fluorescence assay. We demonstrated on a C. elegans AD model the effectiveness of the proposed delivery strategy in vivo. Proteo-LUVs allow efficient administration of the protein, exerting a positive functional readout at very low doses while avoiding the intrinsic toxicity of αs1-Casein. Proteo-LUVs of αs1-Casein represent an effective proof of concept for the exploitation of partially disordered proteins as a therapeutic strategy in mild AD conditions.
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Affiliation(s)
- Angela Paterna
- Institute
of Biophysics, National Research Council, Division of Palermo, Via Ugo La Malfa 153, 90146 Palermo, Italy
| | - Pamela Santonicola
- Institute
of Biosciences and Bioresources, Division of Napoli, Via Pietro Castellino 111, 80131 Napoli, Italy
- Department
of Medicine and Health Sciences, University
of Molise, 86100 Campobasso, Italy
| | - Giulia Di Prima
- Department
of Biological, Chemical and Pharmaceutical Sciences and Technologies, University of Palermo, 90123 Palermo, Italy
| | - Estella Rao
- Institute
of Biophysics, National Research Council, Division of Palermo, Via Ugo La Malfa 153, 90146 Palermo, Italy
| | - Samuele Raccosta
- Institute
of Biophysics, National Research Council, Division of Palermo, Via Ugo La Malfa 153, 90146 Palermo, Italy
| | - Giuseppina Zampi
- Institute
of Biosciences and Bioresources, Division of Napoli, Via Pietro Castellino 111, 80131 Napoli, Italy
| | - Claudio Russo
- Department
of Medicine and Health Sciences, University
of Molise, 86100 Campobasso, Italy
- Consorzio
Interuniversitario in Ingegneria e Medicina (COIIM), Via F. De Sanctis, 86100 Campobasso, Italy
| | - Oscar Moran
- Institute
of Biophysics, National Research Council, Division of Genova, Via De Marini 6, 16149 Genova, Italy
| | - Mauro Manno
- Institute
of Biophysics, National Research Council, Division of Palermo, Via Ugo La Malfa 153, 90146 Palermo, Italy
| | - Elia Di Schiavi
- Institute
of Biosciences and Bioresources, Division of Napoli, Via Pietro Castellino 111, 80131 Napoli, Italy
| | - Fabio Librizzi
- Institute
of Biophysics, National Research Council, Division of Palermo, Via Ugo La Malfa 153, 90146 Palermo, Italy
| | - Rita Carrotta
- Institute
of Biophysics, National Research Council, Division of Palermo, Via Ugo La Malfa 153, 90146 Palermo, Italy
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Murakami T, Kaku T, Tsukakoshi K, Iwaide S, Itoh Y, Hisada M, Nomura K, Kubo R, Ikebukuro K, Sassa-O'Brien Y, Kametani F. Identification of novel amyloidosis in dogs: α-S1-casein acquires amyloidogenicity in mammary tumor by overexpression and N-terminal truncation. Vet Pathol 2023; 60:203-213. [PMID: 36680468 DOI: 10.1177/03009858221148511] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Mammary tumor-associated amyloidosis (MTAA) in dogs is characterized by amyloid deposition in the stroma of mammary adenoma or carcinoma; however, the amyloid precursor protein remains unknown. We attempted to identify an amyloid precursor protein and elucidated its etiology by characterizing 5 cases of canine MTAA. Proteomic analyses of amyloid extracts from formalin-fixed paraffin-embedded specimens revealed α-S1-casein (CASA1) as a prime candidate and showed the N-terminal truncation of canine CASA1. Both immunohistochemistry and immunoelectron microscopy showed that amyloid deposits or fibrils in MTAA cases were positive for CASA1. Reverse transcription-polymerase chain reaction and quantitative polymerase chain reaction revealed the complete mRNA sequence encoding CASA1, whose expression was significantly higher in the amyloid-positive group. The recombinant protein of the N-terminal-truncated canine CASA1 and the synthetic peptides derived from canine and human CASA1 formed amyloid-like fibrils in vitro. Structural prediction suggested that the N-terminal region of CASA1 was disordered. Previously, full-length CASA1 was reported to inhibit the amyloidogenesis of other proteins; however, we demonstrated that CASA1 acquires amyloidogenicity via excessive synthesis followed by truncation of its disordered N-terminal region. By identifying a novel in vivo amyloidogenic protein in animals and revealing key mechanistic details of its associated pathology, this study provides valuable insights into the integrated understanding of related proteopathies.
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Affiliation(s)
- Tomoaki Murakami
- Tokyo University of Agriculture and Technology, Fuchu-shi, Japan
| | - Toshisuke Kaku
- Tokyo University of Agriculture and Technology, Koganei-shi, Japan
| | - Kaori Tsukakoshi
- Tokyo University of Agriculture and Technology, Koganei-shi, Japan
| | - Susumu Iwaide
- Tokyo University of Agriculture and Technology, Fuchu-shi, Japan
| | - Yoshiyuki Itoh
- Tokyo University of Agriculture and Technology, Fuchu-shi, Japan
| | - Miki Hisada
- Tokyo University of Agriculture and Technology, Fuchu-shi, Japan
| | | | - Rikako Kubo
- Tokyo University of Agriculture and Technology, Koganei-shi, Japan
| | | | | | - Fuyuki Kametani
- Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
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5
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Spatharas PM, Nasi GI, Tsiolaki PL, Theodoropoulou MK, Papandreou NC, Hoenger A, Trougakos IP, Iconomidou VA. Clusterin in Alzheimer's disease: An amyloidogenic inhibitor of amyloid formation? Biochim Biophys Acta Mol Basis Dis 2022; 1868:166384. [DOI: 10.1016/j.bbadis.2022.166384] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Revised: 02/20/2022] [Accepted: 03/07/2022] [Indexed: 12/14/2022]
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6
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Small Angle X-ray Scattering Sensing Membrane Composition: The Role of Sphingolipids in Membrane-Amyloid β-Peptide Interaction. BIOLOGY 2021; 11:biology11010026. [PMID: 35053023 PMCID: PMC8772848 DOI: 10.3390/biology11010026] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/04/2021] [Revised: 12/09/2021] [Accepted: 12/22/2021] [Indexed: 12/02/2022]
Abstract
Simple Summary The early impairments in Alzheimer’s disease are related to neuronal membrane damage. Different lipids are present in biological membranes, playing relevant physiological roles. Some of them, such as sphingomyelin, cholesterol, and ganglioside GM1, interact with each other and, importantly, with the Aβ peptide. Here, these interactions are studied using small angle X-ray scattering in model membrane systems, such as large unilamellar liposomes. This technique gives information on the width of the bilayer and reveals structural differences due to the different lipid compositions, as well as some small differences due to the presence of the Aβ peptide. The analysis highlights the concentration-dependent effect of GM1 on membrane thickness and the interaction with the Aβ-peptide, together with the inhibiting effect that the presence of sphingomyelin has on the GM1–Aβ interaction. Abstract The early impairments appearing in Alzheimer’s disease are related to neuronal membrane damage. Both aberrant Aβ species and specific membrane components play a role in promoting aggregation, deposition, and signaling dysfunction. Ganglioside GM1, present with cholesterol and sphingomyelin in lipid rafts, preferentially interacts with the Aβ peptide. GM1 at physiological conditions clusters in the membrane, the assembly also involves phospholipids, sphingomyelin, and cholesterol. The structure of large unilamellar vesicles (LUV), made of a basic POPC:POPS matrix in a proportion of 9:1, and containing different amounts of GM1 (1%, 3%, and 4% mol/mol) in the presence of 5% mol/mol sphingomyelin and 15% mol/mol cholesterol, was studied using small angle X-ray scattering (SAXS). The effect of the membrane composition on the LUVs–Aβ-peptide interaction, both for Aβ1–40 and Aβ1–42 variants, was, thus, monitored. The presence of GM1 leads to a significant shift of the main peak, towards lower scattering angles, up to 6% of the initial value with SM and 8% without, accompanied by an opposite shift of the first minimum, up to 21% and 24% of the initial value, respectively. The analysis of the SAXS spectra, using a multi-Gaussian model for the electronic density profile, indicated differences in the bilayer of the various compositions. An increase in the membrane thickness, by 16% and 12% when 2% and 3% mol/mol GM1 was present, without and with SM, respectively, was obtained. Furthermore, in these cases, in the presence of Aβ40, a very small decrease of the bilayer thickness, less than 4% and 1%, respectively, was derived, suggesting the inhibiting effect that the presence of sphingomyelin has on the GM1–Aβ interaction.
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7
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Andrikopoulos N, Song Z, Wan X, Douek AM, Javed I, Fu C, Xing Y, Xin F, Li Y, Kakinen A, Koppel K, Qiao R, Whittaker AK, Kaslin J, Davis TP, Song Y, Ding F, Ke PC. Inhibition of Amyloid Aggregation and Toxicity with Janus Iron Oxide Nanoparticles. CHEMISTRY OF MATERIALS : A PUBLICATION OF THE AMERICAN CHEMICAL SOCIETY 2021; 33:6484-6500. [PMID: 34887621 PMCID: PMC8651233 DOI: 10.1021/acs.chemmater.1c01947] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Amyloid aggregation is a ubiquitous form of protein misfolding underlying the pathologies of Alzheimer's disease (AD), Parkinson's disease (PD) and type 2 diabetes (T2D), three primary forms of human amyloid diseases. While much has been learned about the origin, diagnosis and management of these neurological and metabolic disorders, no cure is currently available due in part to the dynamic and heterogeneous nature of the toxic oligomers induced by amyloid aggregation. Here we synthesized beta casein-coated iron oxide nanoparticles (βCas IONPs) via a BPA-P(OEGA-b-DBM) block copolymer linker. Using a thioflavin T kinetic assay, transmission electron microscopy, Fourier transform infrared spectroscopy, discrete molecular dynamics simulations and cell viability assays, we examined the Janus characteristics and the inhibition potential of βCas IONPs against the aggregation of amyloid beta (Aβ), alpha synuclein (αS) and human islet amyloid polypeptide (IAPP) which are implicated in the pathologies of AD, PD and T2D. Incubation of zebrafish embryos with the amyloid proteins largely inhibited hatching and elicited reactive oxygen species, which were effectively rescued by the inhibitor. Furthermore, Aβ-induced damage to mouse brain was mitigated in vivo with the inhibitor. This study revealed the potential of Janus nanoparticles as a new nanomedicine against a diverse range of amyloid diseases.
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Affiliation(s)
- Nicholas Andrikopoulos
- Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, VIC 3052, Australia
| | - Zhiyuan Song
- Department of Physics and Astronomy, Clemson University, Clemson, SC 29634, United States
| | - Xulin Wan
- Key Laboratory of Luminescence Analysis and Molecular Sensing, Ministry of Education, College of Food Science, Southwest University, 2 Tiansheng Rd, Beibei District, Chongqing, 400715, China
| | - Alon M. Douek
- Australian Regenerative Medicine Institute, Monash University, 15 Innovation Walk, Clayton, VIC 3800, Australia
| | - Ibrahim Javed
- Australian Institute for Bioengineering and Nanotechnology, University of Queensland, Brisbane Qld 4072, Australia
| | - Changkui Fu
- Australian Institute for Bioengineering and Nanotechnology, University of Queensland, Brisbane Qld 4072, Australia
| | - Yanting Xing
- Department of Physics and Astronomy, Clemson University, Clemson, SC 29634, United States
| | - Fangyun Xin
- Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, VIC 3052, Australia
- School of Science, Dalian Maritime University, Dalian 116026, China
| | - Yuhuan Li
- Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, VIC 3052, Australia
- Liver Cancer Institute, Zhongshan Hospital, Key Laboratory of Carcinogenesis and Cancer Invasion, Ministry of Education, Fudan University, Shanghai, 200032, China
| | - Aleksandr Kakinen
- Australian Institute for Bioengineering and Nanotechnology, University of Queensland, Brisbane Qld 4072, Australia
| | - Kairi Koppel
- Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, VIC 3052, Australia
| | - Ruirui Qiao
- Australian Institute for Bioengineering and Nanotechnology, University of Queensland, Brisbane Qld 4072, Australia
| | - Andrew K. Whittaker
- Australian Institute for Bioengineering and Nanotechnology, University of Queensland, Brisbane Qld 4072, Australia
| | - Jan Kaslin
- Australian Regenerative Medicine Institute, Monash University, 15 Innovation Walk, Clayton, VIC 3800, Australia
| | - Thomas P. Davis
- Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, VIC 3052, Australia
- Australian Institute for Bioengineering and Nanotechnology, University of Queensland, Brisbane Qld 4072, Australia
- Corresponding Authors: Thomas P. Davis: ; Yang Song, ; Feng Ding: ; Pu Chun Ke:
| | - Yang Song
- Key Laboratory of Luminescence Analysis and Molecular Sensing, Ministry of Education, College of Pharmaceutical Sciences, Southwest University, 2 Tiansheng Rd, Beibei District, Chongqing 400715, China
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China
- Corresponding Authors: Thomas P. Davis: ; Yang Song, ; Feng Ding: ; Pu Chun Ke:
| | - Feng Ding
- Department of Physics and Astronomy, Clemson University, Clemson, SC 29634, United States
- Corresponding Authors: Thomas P. Davis: ; Yang Song, ; Feng Ding: ; Pu Chun Ke:
| | - Pu Chun Ke
- Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, VIC 3052, Australia
- Australian Institute for Bioengineering and Nanotechnology, University of Queensland, Brisbane Qld 4072, Australia
- The GBA National Institute for Nanotechnology Innovation, 136 Kaiyuan Avenue, Guangzhou, 510700, China
- Corresponding Authors: Thomas P. Davis: ; Yang Song, ; Feng Ding: ; Pu Chun Ke:
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8
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Guarrasi V, Rappa GC, Costa MA, Librizzi F, Raimondo M, Di Stefano V, Germanà MA, Vilasi S. Valorization of Apple Peels through the Study of the Effects on the Amyloid Aggregation Process of κ-Casein. Molecules 2021; 26:molecules26082371. [PMID: 33921801 PMCID: PMC8073991 DOI: 10.3390/molecules26082371] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2021] [Revised: 04/13/2021] [Accepted: 04/15/2021] [Indexed: 01/13/2023] Open
Abstract
Waste valorization represents one of the main social challenges when promoting a circular economy and environmental sustainability. Here, we evaluated the effect of the polyphenols extracted from apple peels, normally disposed of as waste, on the amyloid aggregation process of κ-casein from bovine milk, a well-used amyloidogenic model system. The effect of the apple peel extract on protein aggregation was examined using a thioflavin T fluorescence assay, Congo red binding assay, circular dichroism, light scattering, and atomic force microscopy. We found that the phenolic extract from the peel of apples of the cultivar “Fuji”, cultivated in Sicily (Caltavuturo, Italy), inhibited κ-casein fibril formation in a dose-dependent way. In particular, we found that the extract significantly reduced the protein aggregation rate and inhibited the secondary structure reorganization that accompanies κ-casein amyloid formation. Protein-aggregated species resulting from the incubation of κ-casein in the presence of polyphenols under amyloid aggregation conditions were reduced in number and different in morphology.
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Affiliation(s)
- Valeria Guarrasi
- Istituto di Biofisica, Consiglio Nazionale delle Ricerche, Via Ugo La Malfa 153, 90146 Palermo, Italy; (G.C.R.); (M.A.C.); (F.L.); (M.R.); (S.V.)
- Correspondence: ; Tel.: +39-0916809356
| | - Giacoma Cinzia Rappa
- Istituto di Biofisica, Consiglio Nazionale delle Ricerche, Via Ugo La Malfa 153, 90146 Palermo, Italy; (G.C.R.); (M.A.C.); (F.L.); (M.R.); (S.V.)
| | - Maria Assunta Costa
- Istituto di Biofisica, Consiglio Nazionale delle Ricerche, Via Ugo La Malfa 153, 90146 Palermo, Italy; (G.C.R.); (M.A.C.); (F.L.); (M.R.); (S.V.)
| | - Fabio Librizzi
- Istituto di Biofisica, Consiglio Nazionale delle Ricerche, Via Ugo La Malfa 153, 90146 Palermo, Italy; (G.C.R.); (M.A.C.); (F.L.); (M.R.); (S.V.)
| | - Marco Raimondo
- Istituto di Biofisica, Consiglio Nazionale delle Ricerche, Via Ugo La Malfa 153, 90146 Palermo, Italy; (G.C.R.); (M.A.C.); (F.L.); (M.R.); (S.V.)
| | - Vita Di Stefano
- Dipartimento Scienze e Tecnologie Biologiche Chimiche e Farmaceutiche, Università degli Studi di Palermo, Via Archirafi 32, 90123 Palermo, Italy;
| | - Maria Antonietta Germanà
- Dipartimento di Scienze Agrarie, Alimentari e Forestali, Università degli Studi di Palermo, Viale delle Scienze Ed. 4, 90128 Palermo, Italy;
| | - Silvia Vilasi
- Istituto di Biofisica, Consiglio Nazionale delle Ricerche, Via Ugo La Malfa 153, 90146 Palermo, Italy; (G.C.R.); (M.A.C.); (F.L.); (M.R.); (S.V.)
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9
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Inhibition of amyloid beta toxicity in zebrafish with a chaperone-gold nanoparticle dual strategy. Nat Commun 2019; 10:3780. [PMID: 31439844 PMCID: PMC6706415 DOI: 10.1038/s41467-019-11762-0] [Citation(s) in RCA: 115] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2018] [Accepted: 08/04/2019] [Indexed: 12/22/2022] Open
Abstract
Alzheimer’s disease (AD) is the most prevalent form of neurodegenerative disorders, yet no major breakthroughs have been made in AD human trials and the disease remains a paramount challenge and a stigma in medicine. Here we eliminate the toxicity of amyloid beta (Aβ) in a facile, high-throughput zebrafish (Danio rerio) model using casein coated-gold nanoparticles (βCas AuNPs). βCas AuNPs in systemic circulation translocate across the blood brain barrier of zebrafish larvae and sequester intracerebral Aβ42 and its elicited toxicity in a nonspecific, chaperone-like manner. This is evidenced by behavioral pathology, reactive oxygen species and neuronal dysfunction biomarkers assays, complemented by brain histology and inductively coupled plasma-mass spectroscopy. We further demonstrate the capacity of βCas AuNPs in recovering the mobility and cognitive function of adult zebrafish exposed to Aβ. This potent, safe-to-use, and easy-to-apply nanomedicine may find broad use for eradicating toxic amyloid proteins implicated in a range of human diseases. Treating Alzheimer’s disease, one of the most common neurodegenerative diseases, is of wide interest. Here, the authors report on the development of casein coated gold nanoparticles which were able to cross the blood brain barrier and protect against amyloid beta toxicity in a zebrafish model.
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10
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Vilasi S, Carrotta R, Ricci C, Rappa GC, Librizzi F, Martorana V, Ortore MG, Mangione MR. Inhibition of Aβ 1-42 Fibrillation by Chaperonins: Human Hsp60 Is a Stronger Inhibitor than Its Bacterial Homologue GroEL. ACS Chem Neurosci 2019; 10:3565-3574. [PMID: 31298838 DOI: 10.1021/acschemneuro.9b00183] [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] [Indexed: 12/20/2022] Open
Abstract
Alzheimer's disease is a chronic neurodegenerative disease characterized by the accumulation of pathological aggregates of amyloid beta peptide. Many efforts have been focused on understanding peptide aggregation pathways and on identification of molecules able to inhibit aggregation in order to find an effective therapy. As a result, interest in neuroprotective proteins, such as molecular chaperones, has increased as their normal function is to assist in protein folding or to facilitate the disaggregation and/or clearance of abnormal aggregate proteins. Using biophysical techniques, we evaluated the effects of two chaperones, human Hsp60 and bacterial GroEL, on the fibrillogenesis of Aβ1-42. Both chaperonins interfere with Aβ1-42 aggregation, but the effect of Hsp60 is more significant and correlates with its more pronounced flexibility and stronger interaction with ANS, an indicator of hydrophobic regions. Dose-dependent ThT fluorescence kinetics and SAXS experiments reveal that Hsp60 does not change the nature of the molecular processes stochastically leading to the formation of seeds, but strongly delays them by recognition of hydrophobic sites of some peptide species crucial for triggering amyloid formation. Hsp60 reduces the initial chaotic heterogeneity of Aβ1-42 sample at high concentration regimes. The understanding of chaperone action in counteracting pathological aggregation could be a starting point for potential new therapeutic strategies against neurodegenerative diseases.
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Affiliation(s)
- Silvia Vilasi
- Institute of Biophysics, National Research Council, Palermo 90146, Italy
| | - Rita Carrotta
- Institute of Biophysics, National Research Council, Palermo 90146, Italy
| | - Caterina Ricci
- Department of Life and Environmental Sciences, Marche Polytechnic University, Ancona 60131, Italy
| | | | - Fabio Librizzi
- Institute of Biophysics, National Research Council, Palermo 90146, Italy
| | - Vincenzo Martorana
- Institute of Biophysics, National Research Council, Palermo 90146, Italy
| | - Maria Grazia Ortore
- Department of Life and Environmental Sciences, Marche Polytechnic University, Ancona 60131, Italy
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11
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Lambrecht MA, Jansens KJ, Rombouts I, Brijs K, Rousseau F, Schymkowitz J, Delcour JA. Conditions Governing Food Protein Amyloid Fibril Formation. Part II: Milk and Legume Proteins. Compr Rev Food Sci Food Saf 2019; 18:1277-1291. [DOI: 10.1111/1541-4337.12465] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2019] [Revised: 04/26/2019] [Accepted: 05/16/2019] [Indexed: 02/06/2023]
Affiliation(s)
- Marlies A. Lambrecht
- Laboratory of Food Chemistry and Biochemistry and Leuven Food Science and Nutrition Research Centre (LFoRCe)KU Leuven Kasteelpark Arenberg 20 B‐3001 Leuven Belgium
| | - Koen J.A. Jansens
- Laboratory of Food Chemistry and Biochemistry and Leuven Food Science and Nutrition Research Centre (LFoRCe)KU Leuven Kasteelpark Arenberg 20 B‐3001 Leuven Belgium
| | - Ine Rombouts
- Laboratory of Food Chemistry and Biochemistry and Leuven Food Science and Nutrition Research Centre (LFoRCe)KU Leuven Kasteelpark Arenberg 20 B‐3001 Leuven Belgium
| | - Kristof Brijs
- Laboratory of Food Chemistry and Biochemistry and Leuven Food Science and Nutrition Research Centre (LFoRCe)KU Leuven Kasteelpark Arenberg 20 B‐3001 Leuven Belgium
| | - Frederic Rousseau
- Switch LaboratoryVIB B‐3000 Leuven Belgium
- Dept. of Cellular and Molecular MedicineKU Leuven B‐3000 Leuven Belgium
| | - Joost Schymkowitz
- Switch LaboratoryVIB B‐3000 Leuven Belgium
- Dept. of Cellular and Molecular MedicineKU Leuven B‐3000 Leuven Belgium
| | - Jan A. Delcour
- Laboratory of Food Chemistry and Biochemistry and Leuven Food Science and Nutrition Research Centre (LFoRCe)KU Leuven Kasteelpark Arenberg 20 B‐3001 Leuven Belgium
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12
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Zhang T, Loschwitz J, Strodel B, Nagel-Steger L, Willbold D. Interference with Amyloid-β Nucleation by Transient Ligand Interaction. Molecules 2019; 24:E2129. [PMID: 31195746 PMCID: PMC6600523 DOI: 10.3390/molecules24112129] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2019] [Revised: 06/02/2019] [Accepted: 06/04/2019] [Indexed: 12/20/2022] Open
Abstract
Amyloid-β peptide (Aβ) is an intrinsically disordered protein (IDP) associated with Alzheimer's disease. The structural flexibility and aggregation propensity of Aβ pose major challenges for elucidating the interaction between Aβ monomers and ligands. All-D-peptides consisting solely of D-enantiomeric amino acid residues are interesting drug candidates that combine high binding specificity with high metabolic stability. Here we characterized the interaction between the 12-residue all-D-peptide D3 and Aβ42 monomers, and how the interaction influences Aβ42 aggregation. We demonstrate for the first time that D3 binds to Aβ42 monomers with submicromolar affinities. These two highly unstructured molecules are able to form complexes with 1:1 and other stoichiometries. Further, D3 at substoichiometric concentrations effectively slows down the β-sheet formation and Aβ42 fibrillation by modulating the nucleation process. The study provides new insights into the molecular mechanism of how D3 affects Aβ assemblies and contributes to our knowledge on the interaction between two IDPs.
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Affiliation(s)
- Tao Zhang
- Institute of Complex Systems, Structural Biochemistry (ICS-6), Forschungszentrum Jülich, 52425 Jülich, Germany.
- Institut für Physikalische Biologie, Heinrich-Heine-Universität Düsseldorf, 40225 Düsseldorf, Germany.
| | - Jennifer Loschwitz
- Institute of Complex Systems, Structural Biochemistry (ICS-6), Forschungszentrum Jülich, 52425 Jülich, Germany.
- Institute of Theoretical and Computational Chemistry, Heinrich-Heine-Universität Düsseldorf, 40225 Düsseldorf, Germany.
| | - Birgit Strodel
- Institute of Complex Systems, Structural Biochemistry (ICS-6), Forschungszentrum Jülich, 52425 Jülich, Germany.
- Institute of Theoretical and Computational Chemistry, Heinrich-Heine-Universität Düsseldorf, 40225 Düsseldorf, Germany.
| | - Luitgard Nagel-Steger
- Institute of Complex Systems, Structural Biochemistry (ICS-6), Forschungszentrum Jülich, 52425 Jülich, Germany.
- Institut für Physikalische Biologie, Heinrich-Heine-Universität Düsseldorf, 40225 Düsseldorf, Germany.
| | - Dieter Willbold
- Institute of Complex Systems, Structural Biochemistry (ICS-6), Forschungszentrum Jülich, 52425 Jülich, Germany.
- Institut für Physikalische Biologie, Heinrich-Heine-Universität Düsseldorf, 40225 Düsseldorf, Germany.
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13
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Cosentino M, Canale C, Bianchini P, Diaspro A. AFM-STED correlative nanoscopy reveals a dark side in fluorescence microscopy imaging. SCIENCE ADVANCES 2019; 5:eaav8062. [PMID: 31223651 PMCID: PMC6584704 DOI: 10.1126/sciadv.aav8062] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2018] [Accepted: 05/13/2019] [Indexed: 05/19/2023]
Abstract
It is known that the presence of fluorophores can influence the dynamics of molecular processes. Despite this, an affordable technique to control the fluorophore distribution within the sample, as well as the rise of unpredictable anomalous processes induced by the fluorophore itself, is missing. We coupled a stimulated emission depletion (STED) microscope with an atomic force microscope to investigate the formation of amyloid aggregates. In particular, we studied the in vitro aggregation of insulin and two alloforms of β amyloid peptides. We followed standard methods to induce the aggregation and to label the molecules at different dye-to-protein ratios. Only a fraction of the fibrillar aggregates was displayed in STED images, indicating that the labeled molecules did not participate indistinctly to the aggregation process. This finding demonstrates that labeled molecules follow only selected pathways of aggregation, among the multiple that are present in the aggregation reaction.
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Affiliation(s)
- Michela Cosentino
- Department of Nanophysics, Istituto Italiano di Tecnologia, Genova, Italy
- DIBRIS Department, University of Genova, Genova, Italy
| | - Claudio Canale
- Department of Nanophysics, Istituto Italiano di Tecnologia, Genova, Italy
- Department of Physics, University of Genova, Genova, Italy
| | - Paolo Bianchini
- Department of Nanophysics, Istituto Italiano di Tecnologia, Genova, Italy
| | - Alberto Diaspro
- Department of Nanophysics, Istituto Italiano di Tecnologia, Genova, Italy
- Department of Physics, University of Genova, Genova, Italy
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14
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Ricci C, Maccarini M, Falus P, Librizzi F, Mangione MR, Moran O, Ortore MG, Schweins R, Vilasi S, Carrotta R. Amyloid β-Peptide Interaction with Membranes: Can Chaperones Change the Fate? J Phys Chem B 2018; 123:631-638. [DOI: 10.1021/acs.jpcb.8b11719] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Affiliation(s)
- Caterina Ricci
- Dipartimento di Scienze della Vita e dell’Ambiente, Università Politecnica delle Marche, Ancona 60122, Italy
| | - Marco Maccarini
- Université Grenoble Alpes—Laboratoire TIMC/IMAG UMR CNRS 5525, Grenoble 38000, France
| | - Peter Falus
- Science Division, Institut Laue-Langevin, Grenoble Cedex 9 38042, France
| | | | | | - Oscar Moran
- Istituto di Biofisica, CNR, Genova 16149, Italy
| | - Maria Grazia Ortore
- Dipartimento di Scienze della Vita e dell’Ambiente, Università Politecnica delle Marche, Ancona 60122, Italy
| | - Ralf Schweins
- Science Division, Institut Laue-Langevin, Grenoble Cedex 9 38042, France
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15
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Vitale RM, Rispoli V, Desiderio D, Sgammato R, Thellung S, Canale C, Vassalli M, Carbone M, Ciavatta ML, Mollo E, Felicità V, Arcone R, Gavagnin Capoggiani M, Masullo M, Florio T, Amodeo P. In Silico Identification and Experimental Validation of Novel Anti-Alzheimer's Multitargeted Ligands from a Marine Source Featuring a "2-Aminoimidazole plus Aromatic Group" Scaffold. ACS Chem Neurosci 2018; 9:1290-1303. [PMID: 29473731 DOI: 10.1021/acschemneuro.7b00416] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Multitargeting or polypharmacological approaches, looking for single chemical entities retaining the ability to bind two or more molecular targets, are a potentially powerful strategy to fight complex, multifactorial pathologies. Unfortunately, the search for multiligand agents is challenging because only a small subset of molecules contained in molecular databases are bioactive and even fewer are active on a preselected set of multiple targets. However, collections of natural compounds feature a significantly higher fraction of bioactive molecules than synthetic ones. In this view, we searched our library of 1175 natural compounds from marine sources for molecules including a 2-aminoimidazole+aromatic group motif, found in known compounds active on single relevant targets for Alzheimer's disease (AD). This identified two molecules, a pseudozoanthoxanthin (1) and a bromo-pyrrole alkaloid (2), which were predicted by a computational approach to possess interesting multitarget profiles on AD target proteins. Biochemical assays experimentally confirmed their biological activities. The two compounds inhibit acetylcholinesterase, butyrylcholinesterase, and β-secretase enzymes in high- to sub-micromolar range. They are also able to prevent and revert β-amyloid (Aβ) aggregation of both Aβ1-40 and Aβ1-42 peptides, with 1 being more active than 2. Preliminary in vivo studies suggest that compound 1 is able to restore cholinergic cortico-hippocampal functional connectivity.
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Affiliation(s)
- Rosa Maria Vitale
- Institute of Biomolecular Chemistry (ICB), National Research Council (CNR), Comprensorio Olivetti, Ed.70, Via Campi Flegrei, 34, I-80078 Pozzuoli (NA), Italy
| | - Vincenzo Rispoli
- Department of Health Sciences, University Magna Græcia of Catanzaro, Building of Biosciences, University Campus “Salvatore Venuta”, Viale Europa, I-88100 Catanzaro (CZ), Italy
| | - Doriana Desiderio
- Department of Movement Sciences and Wellness, University of Naples “Parthenope”, Via Medina 40, I-80133 Naples (NA), Italy
| | - Roberta Sgammato
- Department of Movement Sciences and Wellness, University of Naples “Parthenope”, Via Medina 40, I-80133 Naples (NA), Italy
| | - Stefano Thellung
- Section of Pharmacology, Department of Internal Medicine and Center of Excellence for Biomedical Research (CEBR), University of Genova, Viale Benedetto XV 2, I-16132 Genoa (GE), Italy
| | - Claudio Canale
- Department of Physics, University of Genova, Via Dodecaneso 33, I-16146 Genoa (GE), Italy
| | - Massimo Vassalli
- Institute of Biophysics, National Research Council, Via De Marini, 10, I-16149 Genoa (GE), Italy
| | - Marianna Carbone
- Institute of Biomolecular Chemistry (ICB), National Research Council (CNR), Comprensorio Olivetti, Ed.70, Via Campi Flegrei, 34, I-80078 Pozzuoli (NA), Italy
| | - Maria Letizia Ciavatta
- Institute of Biomolecular Chemistry (ICB), National Research Council (CNR), Comprensorio Olivetti, Ed.70, Via Campi Flegrei, 34, I-80078 Pozzuoli (NA), Italy
| | - Ernesto Mollo
- Institute of Biomolecular Chemistry (ICB), National Research Council (CNR), Comprensorio Olivetti, Ed.70, Via Campi Flegrei, 34, I-80078 Pozzuoli (NA), Italy
| | - Vera Felicità
- Institute of Biomolecular Chemistry (ICB), National Research Council (CNR), Comprensorio Olivetti, Ed.70, Via Campi Flegrei, 34, I-80078 Pozzuoli (NA), Italy
- Department of Health Sciences, University Magna Græcia of Catanzaro, Building of Biosciences, University Campus “Salvatore Venuta”, Viale Europa, I-88100 Catanzaro (CZ), Italy
| | - Rosaria Arcone
- Department of Movement Sciences and Wellness, University of Naples “Parthenope”, Via Medina 40, I-80133 Naples (NA), Italy
- CEINGE - Advanced Biotechnologies s.c.a r.l., Via Gaetano Salvatore, 486, I-80145 Naples (NA), Italy
| | - Margherita Gavagnin Capoggiani
- Institute of Biomolecular Chemistry (ICB), National Research Council (CNR), Comprensorio Olivetti, Ed.70, Via Campi Flegrei, 34, I-80078 Pozzuoli (NA), Italy
| | - Mariorosario Masullo
- Department of Movement Sciences and Wellness, University of Naples “Parthenope”, Via Medina 40, I-80133 Naples (NA), Italy
- CEINGE - Advanced Biotechnologies s.c.a r.l., Via Gaetano Salvatore, 486, I-80145 Naples (NA), Italy
| | - Tullio Florio
- Section of Pharmacology, Department of Internal Medicine and Center of Excellence for Biomedical Research (CEBR), University of Genova, Viale Benedetto XV 2, I-16132 Genoa (GE), Italy
| | - Pietro Amodeo
- Institute of Biomolecular Chemistry (ICB), National Research Council (CNR), Comprensorio Olivetti, Ed.70, Via Campi Flegrei, 34, I-80078 Pozzuoli (NA), Italy
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16
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Carver JA, Ecroyd H, Truscott RJW, Thorn DC, Holt C. Proteostasis and the Regulation of Intra- and Extracellular Protein Aggregation by ATP-Independent Molecular Chaperones: Lens α-Crystallins and Milk Caseins. Acc Chem Res 2018; 51:745-752. [PMID: 29442498 DOI: 10.1021/acs.accounts.7b00250] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Molecular chaperone proteins perform a diversity of roles inside and outside the cell. One of the most important is the stabilization of misfolding proteins to prevent their aggregation, a process that is potentially detrimental to cell viability. Diseases such as Alzheimer's, Parkinson's, and cataract are characterized by the accumulation of protein aggregates. In vivo, many proteins are metastable and therefore under mild destabilizing conditions have an inherent tendency to misfold, aggregate, and hence lose functionality. As a result, protein levels are tightly regulated inside and outside the cell. Protein homeostasis, or proteostasis, describes the network of biological pathways that ensures the proteome remains folded and functional. Proteostasis is a major factor in maintaining cell, tissue, and organismal viability. We have extensively investigated the structure and function of intra- and extracellular molecular chaperones that operate in an ATP-independent manner to stabilize proteins and prevent their misfolding and subsequent aggregation into amorphous particles or highly ordered amyloid fibrils. These types of chaperones are therefore crucial in maintaining proteostasis under normal and stress (e.g., elevated temperature) conditions. Despite their lack of sequence similarity, they exhibit many common features, i.e., extensive structural disorder, dynamism, malleability, heterogeneity, oligomerization, and similar mechanisms of chaperone action. In this Account, we concentrate on the chaperone roles of α-crystallins and caseins, the predominant proteins in the eye lens and milk, respectively. Intracellularly, the principal ATP-independent chaperones are the small heat-shock proteins (sHsps). In vivo, sHsps are the first line of defense in preventing intracellular protein aggregation. The lens proteins αA- and αB-crystallin are sHsps. They play a crucial role in maintaining solubility of the crystallins (including themselves) with age and hence in lens proteostasis and, ultimately, lens transparency. As there is little metabolic activity and no protein turnover in the lens, crystallins are very long lived proteins. Lens proteostasis is therefore very different to that in normal, metabolically active cells. Crystallins undergo extensive post-translational modification (PTM), including deamidation, racemization, phosphorylation, and truncation, which can alter their stability. Despite this, the lens remains transparent for tens of years, implying that lens proteostasis is intimately integrated with crystallin PTMs. Many PTMs do not significantly alter crystallin stability, solubility, and functionality, which thereby facilitates lens transparency. In the long term, however, extensive accumulation of crystallin PTMs leads to large-scale crystallin aggregation, lens opacification, and cataract formation. Extracellularly, various ATP-independent molecular chaperones exist that exhibit sHsp-like structural and functional features. For example, caseins, the major milk proteins, exhibit chaperone ability by inhibiting the amorphous and amyloid fibrillar aggregation of a diversity of destabilized proteins. Caseins maintain proteostasis within milk by preventing deleterious casein amyloid fibril formation via incorporation of thousands of individual caseins into an amorphous structure known as the casein micelle. Hundreds of nanoclusters of calcium phosphate are sequestered within each casein micelle through interactions with short, highly phosphorylated casein sequences. This results in a stable biofluid that contains a high concentration of potentially amyloidogenic caseins and concentrations of calcium and phosphate that can be far in excess of the solubility of calcium phosphate. Casein micelle formation therefore performs vital roles in neonatal nutrition and calcium homeostasis in the mammary gland.
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Affiliation(s)
- John A. Carver
- Research School of Chemistry, The Australian National University, Acton, ACT 2601, Australia
| | - Heath Ecroyd
- Illawarra Health and Medical Research Institute and School of Biological Sciences, University of Wollongong, Wollongong, NSW 2522, Australia
| | - Roger J. W. Truscott
- Illawarra Health and Medical Research Institute and School of Biological Sciences, University of Wollongong, Wollongong, NSW 2522, Australia
| | - David C. Thorn
- Research School of Chemistry, The Australian National University, Acton, ACT 2601, Australia
| | - Carl Holt
- Institute of Molecular, Cell and Systems Biology, University of Glasgow, Glasgow G12 8QQ, United Kingdom
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17
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Xing Y, Pilkington EH, Wang M, Nowell CJ, Kakinen A, Sun Y, Wang B, Davis TP, Ding F, Ke PC. Lysophosphatidylcholine modulates the aggregation of human islet amyloid polypeptide. Phys Chem Chem Phys 2018; 19:30627-30635. [PMID: 29115353 DOI: 10.1039/c7cp06670h] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Amyloid aggregation of human islet amyloid polypeptide (IAPP) is a hallmark of type 2 diabetes (T2D), a metabolic disease and a global epidemic. Although IAPP is synthesized in pancreatic β-cells, its fibrils and plaques are found in the extracellular space indicating a causative transmembrane process. Numerous biophysical studies have revealed that cell membranes as well as model lipid vesicles promote the aggregation of amyloid-β (associated with Alzheimer's), α-synuclein (associated with Parkinson's) and IAPP, through electrostatic and hydrophobic interactions between the proteins/peptides and lipid membranes. Using a thioflavin T kinetic assay, transmission electron microscopy, circular dichroism spectroscopy, discrete molecular dynamics simulations as well as free energy calculations here we show that micellar lysophosphatidylcholine (LPC), the most abundant lysophospholipid in the blood, inhibited the amyloid aggregation of IAPP through nonspecific interactions while elevating the α-helical peptide secondary structure. This surprising finding suggests a native protective mechanism against IAPP aggregation in vivo.
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Affiliation(s)
- Yanting Xing
- Department of Physics and Astronomy, Clemson University, Clemson, SC 29634, USA.
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18
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Wang Y, Wu C. Quantitative Study of the Oligomerization of Yeast Prion Sup35NM Proteins. Biochemistry 2017; 56:6575-6584. [DOI: 10.1021/acs.biochem.7b00966] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- Yanjing Wang
- Department
of Chemistry, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong, China
| | - Chi Wu
- Department
of Chemistry, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong, China
- Hefei
National Laboratory for Physical Sciences at the Microscale, Department
of Chemical Physics, University of Science and Technology of China, Hefei, Anhui 230026, China
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19
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Ponikova S, Kubackova J, Bednarikova Z, Marek J, Demjen E, Antosova A, Musatov A, Gazova Z. Inhibition of lysozyme amyloidogenesis by phospholipids. Focus on long-chain dimyristoylphosphocholine. Biochim Biophys Acta Gen Subj 2017; 1861:2934-2943. [DOI: 10.1016/j.bbagen.2017.08.023] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2017] [Revised: 08/15/2017] [Accepted: 08/28/2017] [Indexed: 11/16/2022]
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20
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Mannini B, Chiti F. Chaperones as Suppressors of Protein Misfolded Oligomer Toxicity. Front Mol Neurosci 2017; 10:98. [PMID: 28424588 PMCID: PMC5380756 DOI: 10.3389/fnmol.2017.00098] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2017] [Accepted: 03/23/2017] [Indexed: 01/30/2023] Open
Abstract
Chaperones have long been recognized to play well defined functions such as to: (i) assist protein folding and promote formation and maintenance of multisubunit complexes; (ii) mediate protein degradation; (iii) inhibit protein aggregation; and (iv) promote disassembly of undesired aberrant protein aggregates. In addition to these well-established functions, it is increasingly clear that chaperones can also interact with aberrant protein aggregates, such as pre-fibrillar oligomers and fibrils, and inhibit their toxicity commonly associated with neurodegenerative diseases without promoting their disassembly. In particular, the evidence collected so far in different labs, exploiting different experimental approaches and using different chaperones and client aggregated proteins, indicates the existence of two distinct mechanisms of action mediated by the chaperones to neutralize the toxicity of aberrant proteins oligomers: (i) direct binding of the chaperones to the hydrophobic patches exposed on the oligomer/fibril surface, with resulting shielding or masking of the moieties responsible for the aberrant interactions with cellular targets; (ii) chaperone-mediated conversion of aberrant protein aggregates into large and more innocuous species, resulting in a decrease of their surface-to-volume ratio and diffusibility and in deposits more easily manageable by clearance mechanisms, such as autophagy. In this review article we will describe the in vitro and in vivo evidence supporting both mechanisms and how this results in a suppression of the detrimental effects caused by protein misfolded aggregates.
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Affiliation(s)
| | - Fabrizio Chiti
- Section of Biochemistry, Department of Experimental and Clinical Biomedical Sciences, University of FlorenceFlorence, Italy
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21
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Sunde M, Pham CLL, Kwan AH. Molecular Characteristics and Biological Functions of Surface-Active and Surfactant Proteins. Annu Rev Biochem 2017; 86:585-608. [PMID: 28125290 DOI: 10.1146/annurev-biochem-061516-044847] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Many critical biological processes take place at hydrophobic:hydrophilic interfaces, and a wide range of organisms produce surface-active proteins and peptides that reduce surface and interfacial tension and mediate growth and development at these boundaries. Microorganisms produce both small lipid-associated peptides and amphipathic proteins that allow growth across water:air boundaries, attachment to surfaces, predation, and improved bioavailability of hydrophobic substrates. Higher-order organisms produce surface-active proteins with a wide variety of functions, including the provision of protective foam environments for vulnerable reproductive stages, evaporative cooling, and gas exchange across airway membranes. In general, the biological functions supported by these diverse polypeptides require them to have an amphipathic nature, and this is achieved by a diverse range of molecular structures, with some proteins undergoing significant conformational change or intermolecular association to generate the structures that are surface active.
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Affiliation(s)
- Margaret Sunde
- Discipline of Pharmacology, School of Medical Sciences and Australian Institute for Nanoscale Science and Technology, University of Sydney, NSW 2006, Australia; ,
| | - Chi L L Pham
- Discipline of Pharmacology, School of Medical Sciences and Australian Institute for Nanoscale Science and Technology, University of Sydney, NSW 2006, Australia; ,
| | - Ann H Kwan
- School of Life and Environmental Sciences and Australian Institute for Nanoscale Science and Technology, University of Sydney, NSW 2006, Australia;
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22
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Sekar G, Florance I, Sivakumar A, Mukherjee A, Chandrasekaran N. Role of PAMAM-OH dendrimers against the fibrillation pathway of biomolecules. Int J Biol Macromol 2016; 93:1007-1018. [PMID: 27651276 DOI: 10.1016/j.ijbiomac.2016.09.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2016] [Revised: 08/31/2016] [Accepted: 09/01/2016] [Indexed: 12/20/2022]
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23
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Yin T, Xie W, Sun J, Yang L, Liu J. Penetratin Peptide-Functionalized Gold Nanostars: Enhanced BBB Permeability and NIR Photothermal Treatment of Alzheimer's Disease Using Ultralow Irradiance. ACS APPLIED MATERIALS & INTERFACES 2016; 8:19291-302. [PMID: 27411476 DOI: 10.1021/acsami.6b05089] [Citation(s) in RCA: 75] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The structural changes of amyloid-beta (Aβ) from nontoxic monomers into neurotoxic aggregates are implicated with pathogenesis of Alzheimer's disease (AD). Over the past decades, weak disaggregation ability and low permeability to the blood-brain barrier (BBB) may be the main obstacles for major Aβ aggregation blockers. Here, we synthesized penetratin (Pen) peptide loaded poly(ethylene glycol) (PEG)-stabilized gold nanostars (AuNS) modified with ruthenium complex (Ru@Pen@PEG-AuNS), and Ru(II) complex as luminescent probes for tracking drug delivery. We revealed that Ru@Pen@PEG-AuNS could obviously inhibit the formation of Aβ fibrils as well as dissociate preformed fibrous Aβ under the irradiation of near-infrared (NIR) due to the NIR absorption characteristic of AuNS. More importantly, this novel design could be applied in medicine as an appropriate nanovehicle, being highly biocompatible and hemocompatible. In addition, Ru@Pen@PEG-AuNS had excellent neuroprotective effect on the Aβ-induced cellular toxicity by applying NIR irradiation. Meanwhile, Pen peptide could effectively improve the delivery of nanoparticles to the brain in vitro and in vivo, which overcame the major limitation of Aβ aggregation blockers. These consequences illustrated that the enhanced BBB permeability and efficient photothermolysis of Ru@Pen@PEG-AuNS are promising agents in AD therapy.
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Affiliation(s)
- Tiantian Yin
- Department of Chemistry, Jinan University , Guangzhou 510632, China
| | - Wenjie Xie
- Department of Chemistry, Jinan University , Guangzhou 510632, China
| | - Jing Sun
- Department of Chemistry, Jinan University , Guangzhou 510632, China
| | - Licong Yang
- Department of Chemistry, Jinan University , Guangzhou 510632, China
| | - Jie Liu
- Department of Chemistry, Jinan University , Guangzhou 510632, China
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24
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Mangione MR, Vilasi S, Marino C, Librizzi F, Canale C, Spigolon D, Bucchieri F, Fucarino A, Passantino R, Cappello F, Bulone D, San Biagio PL. Hsp60, amateur chaperone in amyloid-beta fibrillogenesis. Biochim Biophys Acta Gen Subj 2016; 1860:2474-2483. [PMID: 27474204 DOI: 10.1016/j.bbagen.2016.07.019] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2016] [Revised: 07/14/2016] [Accepted: 07/24/2016] [Indexed: 10/21/2022]
Abstract
BACKGROUND Molecular chaperones are a very special class of proteins that play essential roles in many cellular processes like folding, targeting and transport of proteins. Moreover, recent evidence indicates that chaperones can act as potentially strong suppressor agents in Alzheimer's disease (AD). Indeed, in vitro experiments demonstrate that several chaperones are able to significantly slow down or suppress aggregation of Aβ peptide and in vivo studies reveal that treatment with specific chaperones or their overexpression can ameliorate some distinct pathological signs characterizing AD. METHODS Here we investigate using a biophysical approach (fluorescence, circular dichroism (CD), transmission electron (TEM) and atomic force (AFM) microscopy, size exclusion chromatography (SEC)) the effect of the human chaperonin Hsp60 on Aβ fibrillogenesis. RESULTS We found that Hsp60 powerfully inhibits Aβ amyloid aggregation, by closing molecular pathways leading to peptide fibrillogenesis. CONCLUSIONS We observe that Hsp60 inhibits Aβ aggregation through a more complex mechanism than a simple folding chaperone action. The action is specifically directed toward the early oligomeric species behaving as aggregation seeds for on-pathway amyloid fibrillogenesis. GENERAL SIGNIFICANCE Understanding the specificity of the molecular interactions of Hsp60 with amyloid Aβ peptide allowed us to emphasize the important aspects to be taken into consideration when considering the recent promising therapeutic strategies for neurodegeneration.
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Affiliation(s)
| | - Silvia Vilasi
- Institute of Biophysics, National Research Council, Palermo, Italy.
| | - Claudia Marino
- Institute of Biophysics, National Research Council, Palermo, Italy; Department of Neurology, University of Texas Medical Branch, Galveston, TX, USA; Department of Experimental Biomedicine and Clinical Neurosciences, University of Palermo, Italy
| | - Fabio Librizzi
- Institute of Biophysics, National Research Council, Palermo, Italy
| | - Claudio Canale
- Nanophysics Department, Istituto Italiano di Tecnologia, Italy
| | - Dario Spigolon
- Institute of Biophysics, National Research Council, Palermo, Italy; Department of Physics and Chemistry, University of Palermo, Palermo, Italy
| | - Fabio Bucchieri
- Department of Experimental Biomedicine and Clinical Neurosciences, University of Palermo, Italy; Institute of Biomedicine and Molecular Immunology, National Research Council, Palermo, Italy; Euro-Mediterranean Institute of Science and Technology, Palermo, Italy
| | - Alberto Fucarino
- Department of Experimental Biomedicine and Clinical Neurosciences, University of Palermo, Italy; Euro-Mediterranean Institute of Science and Technology, Palermo, Italy
| | - Rosa Passantino
- Institute of Biophysics, National Research Council, Palermo, Italy
| | - Francesco Cappello
- Institute of Biophysics, National Research Council, Palermo, Italy; Department of Experimental Biomedicine and Clinical Neurosciences, University of Palermo, Italy; Euro-Mediterranean Institute of Science and Technology, Palermo, Italy
| | - Donatella Bulone
- Institute of Biophysics, National Research Council, Palermo, Italy
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Vordenbäumen S, Saenger T, Braukmann A, Tahan T, Bleck E, Jose J, Schneider M. Human casein alpha s1 induces proinflammatory cytokine expression in monocytic cells by TLR4 signaling. Mol Nutr Food Res 2016; 60:1079-89. [DOI: 10.1002/mnfr.201500792] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2015] [Revised: 01/13/2016] [Accepted: 02/04/2016] [Indexed: 01/08/2023]
Affiliation(s)
- Stefan Vordenbäumen
- Medical Faculty, Department of Rheumatology and Hiller Research Unit Rheumatology; Heinrich-Heine-University Düsseldorf; Düsseldorf Germany
| | - Thorsten Saenger
- Institute of Pharmaceutical and Medicinal Chemistry, PharmaCampus; Westfälische Wilhelms-University Münster; Münster Germany
| | - Achim Braukmann
- Institute of Pharmaceutical and Medicinal Chemistry, PharmaCampus; Westfälische Wilhelms-University Münster; Münster Germany
| | - Tamara Tahan
- Institute of Pharmaceutical and Medicinal Chemistry, PharmaCampus; Westfälische Wilhelms-University Münster; Münster Germany
| | - Ellen Bleck
- Medical Faculty, Department of Rheumatology and Hiller Research Unit Rheumatology; Heinrich-Heine-University Düsseldorf; Düsseldorf Germany
| | - Joachim Jose
- Institute of Pharmaceutical and Medicinal Chemistry, PharmaCampus; Westfälische Wilhelms-University Münster; Münster Germany
| | - Matthias Schneider
- Medical Faculty, Department of Rheumatology and Hiller Research Unit Rheumatology; Heinrich-Heine-University Düsseldorf; Düsseldorf Germany
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26
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Nicastro MC, Spigolon D, Librizzi F, Moran O, Ortore MG, Bulone D, Biagio PLS, Carrotta R. Amyloid β-peptide insertion in liposomes containing GM1-cholesterol domains. Biophys Chem 2016; 208:9-16. [DOI: 10.1016/j.bpc.2015.07.010] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2015] [Revised: 07/17/2015] [Accepted: 07/30/2015] [Indexed: 11/17/2022]
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27
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Pan K, Zhong Q. Amyloid-like fibrils formed from intrinsically disordered caseins: physicochemical and nanomechanical properties. SOFT MATTER 2015; 11:5898-904. [PMID: 26112282 DOI: 10.1039/c5sm01037c] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Amyloid-like fibrils are studied because of their significance in understanding pathogenesis and creating functional materials. Amyloid-like fibrils have been studied by heating globular proteins at acidic conditions. In the present study, intrinsically disordered α-, β-, and κ-caseins were studied to form amyloid-like fibrils at pH 2.0 and 90 °C. No fibrils were observed for α-caseins, and acid hydrolysis was found to be the rate-limiting step of fibrillation of β- and κ-caseins. An increase of β-sheet structure was observed after fibrillation. Nanomechanic analysis of long amyloid-like fibrils using peak-force quantitative nanomechanical atomic force microscopy showed the lowest and highest Young's modulus for β-casein (2.35 ± 0.29 GPa) and κ-casein (4.14 ± 0.66 GPa), respectively. The dispersion with β-casein fibrils had a viscosity more than 10 and 5 times higher than those of κ-casein and β-lactoglobulin, respectively, at 0.1 s(-1) at comparable concentrations. The current findings may assist not only the understanding of amyloid fibril formation but also the development of novel functional materials from disordered proteins.
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Affiliation(s)
- Kang Pan
- Department of Food Science and Technology, University of Tennessee in Knoxville, USA.
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28
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Ghahghaei A, Shahraki S. Inhibitory Effect of β-Casein on the Amyloid Fibril Formation of Aβ1–40 Associated with Alzheimer’s Disease. Int J Pept Res Ther 2015. [DOI: 10.1007/s10989-015-9482-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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29
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30
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Arosio P, Knowles TPJ, Linse S. On the lag phase in amyloid fibril formation. Phys Chem Chem Phys 2015; 17:7606-18. [PMID: 25719972 PMCID: PMC4498454 DOI: 10.1039/c4cp05563b] [Citation(s) in RCA: 541] [Impact Index Per Article: 60.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2014] [Accepted: 02/03/2015] [Indexed: 12/11/2022]
Abstract
The formation of nanoscale amyloid fibrils from normally soluble peptides and proteins is a common form of self-assembly phenomenon that has fundamental connections with biological functions and human diseases. The kinetics of this process has been widely studied and exhibits on a macroscopic level three characteristic stages: a lag phase, a growth phase and a final plateau regime. The question of which molecular events take place during each one of these phases has been a central element in the quest for a mechanism of amyloid formation. In this review, we discuss the nature and molecular origin of the lag-phase in amyloid formation by making use of tools and concepts from physical chemistry, in particular from chemical reaction kinetics. We discuss how, in macroscopic samples, it has become apparent that the lag-phase is not a waiting time for nuclei to form. Rather, multiple parallel processes exist and typically millions of primary nuclei form during the lag phase from monomers in solution. Thus, the lag-time represents a time that is required for the nuclei that are formed early on in the reaction to grow and proliferate in order to reach an aggregate concentration that is readily detected in bulk assays. In many cases, this proliferation takes place through secondary nucleation, where fibrils may present a catalytic surface for the formation of new aggregates. Fibrils may also break (fragmentation) and thereby provide new ends for elongation. Thus, at least two - primary nucleation and elongation - and in many systems at least four - primary nucleation, elongation, secondary nucleation and fragmentation - microscopic processes occur during the lag phase. Moreover, these same processes occur during all three phases of the macroscopic aggregation process, albeit at different rates as governed by rate constants and by the concentration of reacting species at each point in time.
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Affiliation(s)
- Paolo Arosio
- Chemistry Department , University of Cambridge , Lensfield road , Cambridge , UK
| | - Tuomas P. J. Knowles
- Chemistry Department , University of Cambridge , Lensfield road , Cambridge , UK
| | - Sara Linse
- Department of Biochemistry and Structural Biology , Chemical Centre , Lund University , P. O. Box 124 , SE221 00 Lund , Sweden .
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31
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32
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Librizzi F, Carrotta R, Spigolon D, Bulone D, San Biagio PL. α-Casein Inhibits Insulin Amyloid Formation by Preventing the Onset of Secondary Nucleation Processes. J Phys Chem Lett 2014; 5:3043-3048. [PMID: 26278257 DOI: 10.1021/jz501570m] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
α-Casein is known to inhibit the aggregation of several proteins, including the amyloid β-peptide, by mechanisms that are not yet completely clear. We studied its effects on insulin, a system extensively used to investigate the properties of amyloids, many of which are common to all proteins and peptides. In particular, as for other proteins, insulin aggregation is affected by secondary nucleation pathways. We found that α-casein strongly delays insulin amyloid formation, even at extremely low doses, when the aggregation process is characterized by secondary nucleation. At difference, it has a vanishing inhibitory effect on the initial oligomer formation, which is observed at high concentration and does not involve any secondary nucleation pathway. These results indicate that an efficient inhibition of amyloid formation can be achieved by chaperone-like systems, by sequestering the early aggregates, before they can trigger the exponential proliferation brought about by secondary nucleation mechanisms.
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Affiliation(s)
- Fabio Librizzi
- Institute of Biophysics, UOS Palermo, National Research Council, Via Ugo La Malfa 153, Palermo 90146, Italy
| | - Rita Carrotta
- Institute of Biophysics, UOS Palermo, National Research Council, Via Ugo La Malfa 153, Palermo 90146, Italy
| | - Dario Spigolon
- Institute of Biophysics, UOS Palermo, National Research Council, Via Ugo La Malfa 153, Palermo 90146, Italy
| | - Donatella Bulone
- Institute of Biophysics, UOS Palermo, National Research Council, Via Ugo La Malfa 153, Palermo 90146, Italy
| | - Pier Luigi San Biagio
- Institute of Biophysics, UOS Palermo, National Research Council, Via Ugo La Malfa 153, Palermo 90146, Italy
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33
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Assarsson A, Linse S, Cabaleiro-Lago C. Effects of polyamino acids and polyelectrolytes on amyloid β fibril formation. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2014; 30:8812-8. [PMID: 24978100 PMCID: PMC4191606 DOI: 10.1021/la501414j] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
The fibril formation of the neurodegenerative peptide amyloid β (Aβ42) is sensitive to solution conditions, and several proteins and peptides have been found to retard the process. Aβ42 fibril formation was followed with ThT fluorescence in the presence of polyamino acids (poly-glutamic acid, poly-lysine, and poly-threonine) and other polymers (poly(acrylic acid), poly(ethylenimine), and poly(diallyldimethylammonium chloride). An accelerating effect on the Aβ42 aggregation process is observed from all positively charged polymers, while no effect is seen from the negative or neutral polymers. The accelerating effect is dependent on the concentration of positive polymer in a highly reproducible manner. Acceleration is observed from a 1:500 polymer to Aβ42 weight ratio and up. Polyamino acids and the other polymers exert quantitatively the same effect at the same concentrations based on weight. Fibrils are formed in all cases as verified by transmission electron microscopy. The concentrations of polymers required for acceleration are too low to affect the Aβ42 aggregation process through increased ionic strength or molecular crowding effects. Instead, the acceleration seems to arise from the locally increased Aβ42 concentration near the polymers, which favors association and affects the electrostatic environment of the peptide.
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34
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Vilasi S, Carrotta R, Mangione MR, Campanella C, Librizzi F, Randazzo L, Martorana V, Marino Gammazza A, Ortore MG, Vilasi A, Pocsfalvi G, Burgio G, Corona D, Palumbo Piccionello A, Zummo G, Bulone D, Conway de Macario E, Macario AJL, San Biagio PL, Cappello F. Human Hsp60 with its mitochondrial import signal occurs in solution as heptamers and tetradecamers remarkably stable over a wide range of concentrations. PLoS One 2014; 9:e97657. [PMID: 24830947 PMCID: PMC4022648 DOI: 10.1371/journal.pone.0097657] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2014] [Accepted: 04/21/2014] [Indexed: 11/23/2022] Open
Abstract
It has been established that Hsp60 can accumulate in the cytosol in various pathological conditions, including cancer and chronic inflammatory diseases. Part or all of the cytosolic Hsp60 could be naïve, namely, bear the mitochondrial import signal (MIS), but neither the structure nor the in solution oligomeric organization of this cytosolic molecule has still been elucidated. Here we present a detailed study of the structure and self-organization of naïve cytosolic Hsp60 in solution. Results were obtained by different biophysical methods (light and X ray scattering, single molecule spectroscopy and hydrodynamics) that all together allowed us to assay a wide range of concentrations of Hsp60. We found that Naïve Hsp60 in aqueous solution is assembled in very stable heptamers and tetradecamers at all concentrations assayed, without any trace of monomer presence.
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Affiliation(s)
- Silvia Vilasi
- Institute of Biophysics, National Research Council, Palermo, Italy
| | - Rita Carrotta
- Institute of Biophysics, National Research Council, Palermo, Italy
| | | | - Claudia Campanella
- Department of Experimental Biomedicine and Clinical Neurosciences, University of Palermo, Palermo, Italy
- Euro-Mediterranean Institute of Science and Technology, Palermo, Italy
| | - Fabio Librizzi
- Institute of Biophysics, National Research Council, Palermo, Italy
| | | | | | - Antonella Marino Gammazza
- Department of Experimental Biomedicine and Clinical Neurosciences, University of Palermo, Palermo, Italy
- Euro-Mediterranean Institute of Science and Technology, Palermo, Italy
| | - Maria Grazia Ortore
- Department of Life and Environmental Sciences and National Interuniversity Consortium for the Physical Sciences of Matter, Marche Polytechnic University, Ancona, Italy
| | - Annalisa Vilasi
- Institute of Biosciences and Bioresources, National Research Council, Napoli, Italy
| | - Gabriella Pocsfalvi
- Institute of Biosciences and Bioresources, National Research Council, Napoli, Italy
| | - Giosalba Burgio
- Department of biological chemical and pharmaceutical sciences and technologies, University of Palermo, Palermo, Italy
| | - Davide Corona
- Department of biological chemical and pharmaceutical sciences and technologies, University of Palermo, Palermo, Italy
| | - Antonio Palumbo Piccionello
- Institute of Biophysics, National Research Council, Palermo, Italy
- Department of biological chemical and pharmaceutical sciences and technologies, University of Palermo, Palermo, Italy
| | - Giovanni Zummo
- Department of Experimental Biomedicine and Clinical Neurosciences, University of Palermo, Palermo, Italy
| | - Donatella Bulone
- Institute of Biophysics, National Research Council, Palermo, Italy
| | - Everly Conway de Macario
- Department of Microbiology and Immunology, School of Medicine, University of Maryland at Baltimore, and Institute of Marine and Environmental Technology, Columbus Center, Baltimore, Maryland, United States of America
| | - Alberto J. L. Macario
- Euro-Mediterranean Institute of Science and Technology, Palermo, Italy
- Department of Microbiology and Immunology, School of Medicine, University of Maryland at Baltimore, and Institute of Marine and Environmental Technology, Columbus Center, Baltimore, Maryland, United States of America
| | | | - Francesco Cappello
- Institute of Biophysics, National Research Council, Palermo, Italy
- Department of Experimental Biomedicine and Clinical Neurosciences, University of Palermo, Palermo, Italy
- Euro-Mediterranean Institute of Science and Technology, Palermo, Italy
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35
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Assarsson A, Hellstrand E, Cabaleiro-Lago C, Linse S. Charge dependent retardation of amyloid β aggregation by hydrophilic proteins. ACS Chem Neurosci 2014; 5:266-74. [PMID: 24475785 DOI: 10.1021/cn400124r] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The aggregation of amyloid β peptides (Aβ) into amyloid fibrils is implicated in the pathology of Alzheimer's disease. In light of the increasing number of proteins reported to retard Aβ fibril formation, we investigated the influence of small hydrophilic model proteins of different charge on Aβ aggregation kinetics and their interaction with Aβ. We followed the amyloid fibril formation of Aβ40 and Aβ42 using thioflavin T fluorescence in the presence of six charge variants of calbindin D9k and single-chain monellin. The formation of fibrils was verified with transmission electron microscopy. We observe retardation of the aggregation process from proteins with net charge +8, +2, -2, and -4, whereas no effect is observed for proteins with net charge of -6 and -8. The single-chain monellin mutant with the highest net charge, scMN+8, has the largest retarding effect on the amyloid fibril formation process, which is noticeably delayed at as low as a 0.01:1 scMN+8 to Aβ40 molar ratio. scMN+8 is also the mutant with the fastest association to Aβ40 as detected by surface plasmon resonance, although all retarding variants of calbindin D9k and single-chain monellin bind to Aβ40.
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Affiliation(s)
- Anna Assarsson
- Divisions
of †Biochemistry and
Structural Biology and ‡Biophysical Chemistry, Lund University, P.O. Box 124, SE 221 00 Lund, Sweden
| | - Erik Hellstrand
- Divisions
of †Biochemistry and
Structural Biology and ‡Biophysical Chemistry, Lund University, P.O. Box 124, SE 221 00 Lund, Sweden
| | - Celia Cabaleiro-Lago
- Divisions
of †Biochemistry and
Structural Biology and ‡Biophysical Chemistry, Lund University, P.O. Box 124, SE 221 00 Lund, Sweden
| | - Sara Linse
- Divisions
of †Biochemistry and
Structural Biology and ‡Biophysical Chemistry, Lund University, P.O. Box 124, SE 221 00 Lund, Sweden
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36
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Du X, Li H, Wang Z, Qiu S, Liu Q, Ni J. Selenoprotein P and selenoprotein M block Zn2+ -mediated Aβ42 aggregation and toxicity. Metallomics 2014; 5:861-70. [PMID: 23652332 DOI: 10.1039/c3mt20282h] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Aggregation and cytotoxicity of the amyloid-β (Aβ) peptide with transition metal ions in neuronal cells have been suggested to be involved in the progression of Alzheimer's disease (AD). A therapeutic strategy to combat this incurable disease is to design chemical agents to target metal-Aβ species. Selenoproteins are a group of special proteins that contain the 21st amino acid Sec in their sequence. Due to the presence of Sec, studies of this group of proteins are basically focused on their roles in regulating redox potential and scavenging reactive oxygen species. Here, we reported that the His-rich domain of selenoprotein P (SelP-H) and the Sec-to-Cys mutant selenoprotein M (SelM') are capable of binding transition metal ions and modulating the Zn(2+)-mediated Aβ aggregation, ROS production and neurotoxicity. SelM' (U48C) and SelP-H were found to coordinate 0.5 and 2 molar equivalents of Zn(2+)/Cd(2+) with micromolar and submicromolar affinities, respectively. Metal binding induced the structural changes in SelP-H and SelM' according to the circular dichorism spectra. Zn(2+) binding to Aβ42 almost completely suppressed Aβ42 fibrillization, which could be significantly restored by SelP-H and SelM', as observed by thioflavin T (ThT) fluorescence and transmission electron microscopy (TEM). Interestingly, both SelP-H and SelM' inhibited Zn(2+)-Aβ42-induced neurotoxicity and the intracellular ROS production in living cells. These studies suggest that SelP and SelM may play certain roles in regulating redox balance as well as metal homeostasis.
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Affiliation(s)
- Xiubo Du
- College of Life Sciences, Shenzhen Key Laboratory of Microbial Genetic Engineering, Shenzhen University, Shenzhen, China
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37
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Vordenbäumen S, Braukmann A, Altendorfer I, Bleck E, Jose J, Schneider M. Human casein alpha s1 (CSN1S1) skews in vitro differentiation of monocytes towards macrophages. BMC Immunol 2013; 14:46. [PMID: 24083466 PMCID: PMC3850642 DOI: 10.1186/1471-2172-14-46] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2013] [Accepted: 09/30/2013] [Indexed: 11/10/2022] Open
Abstract
Background The milk-derived protein human Casein alpha s1 (CSN1S1) has recently been detected in blood cells and was shown to possess proinflammatory properties. In the present study, we investigated the effect of CSN1S1 on the differentiation of monocytes. Methods Primary human monocytes were stimulated with recombinant CSN1S1 and compared to cells stimulated with GM-CSF/IL-4 or M-CSF/IFNγ. Morphological changes were assessed by microscopy and quantification of surface markers of differentiation by FACS analysis. Phagocytic activity of CSN1S1 stimulated cells was measured by quantification of zymosan labeled particle uptake. The role of mitogen activated protein kinases for CSN1S1-induced differentiation of monocytes and proinflammatory cytokine expression was assessed by supplementation of specific inhibitors. Results CSN1S1 at a concentration of 10 μg/ml resulted in morphological changes (irregular shape, pseudopodia) and aggregation of cells, comparable to changes observed in M-CSF/IFNγ differentiated macrophages. Surface marker expression was altered after 24 h with an upregulation of CD14 (mean 2.5 fold) and CD64 (1.9 fold) in CSN1S1 stimulated cells. CSN1S1 treated cells showed a characteristic surface marker pattern for macrophages after 120 h of incubation (CD14high, CD64high, CD83low, CD1alow) comparable to changes observed in M-CSF/IFNγ treated monocytes. Furthermore, phagocytic activity was increased 1.4 and 1.9 fold following stimulation with 10 μg/ml CSN1S1 after 24 and 48 h, respectively. Early GM-CSF, but not GM-CSF/IL-4 induced differentiation of monocytes towards dendritic cells (DC) was inhibited by addition of CSN1S1. Finally, CSN1S1 induced upregulation of CD14 was impeded by inhibition of ERK1/2, while inhibition of the mitogen activated protein kinases JNK and p38 did not influence cellular differentiation. However, JNK and p38 inhibitors impeded CSN1S1 induced secretion of the proinflammatory cytokines IL-1b or IL-6. Conclusions CSN1S1 skews in vitro differentiation of monocytes towards a macrophage-like phenotype. Data is accumulating that functions of CSN1S1 are beyond nutritional properties and include immunomodulatory effects.
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Affiliation(s)
- Stefan Vordenbäumen
- Heinrich-Heine-University Düsseldorf, Department of Rheumatology, Moorenstr, 5, 40225 Düsseldorf, Germany.
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Holt C, Carver JA, Ecroyd H, Thorn DC. Invited review: Caseins and the casein micelle: their biological functions, structures, and behavior in foods. J Dairy Sci 2013; 96:6127-46. [PMID: 23958008 DOI: 10.3168/jds.2013-6831] [Citation(s) in RCA: 286] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2013] [Accepted: 06/09/2013] [Indexed: 12/27/2022]
Abstract
A typical casein micelle contains thousands of casein molecules, most of which form thermodynamically stable complexes with nanoclusters of amorphous calcium phosphate. Like many other unfolded proteins, caseins have an actual or potential tendency to assemble into toxic amyloid fibrils, particularly at the high concentrations found in milk. Fibrils do not form in milk because an alternative aggregation pathway is followed that results in formation of the casein micelle. As a result of forming micelles, nutritious milk can be secreted and stored without causing either pathological calcification or amyloidosis of the mother's mammary tissue. The ability to sequester nanoclusters of amorphous calcium phosphate in a stable complex is not unique to caseins. It has been demonstrated using a number of noncasein secreted phosphoproteins and may be of general physiological importance in preventing calcification of other biofluids and soft tissues. Thus, competent noncasein phosphoproteins have similar patterns of phosphorylation and the same type of flexible, unfolded conformation as caseins. The ability to suppress amyloid fibril formation by forming an alternative amorphous aggregate is also not unique to caseins and underlies the action of molecular chaperones such as the small heat-shock proteins. The open structure of the protein matrix of casein micelles is fragile and easily perturbed by changes in its environment. Perturbations can cause the polypeptide chains to segregate into regions of greater and lesser density. As a result, the reliable determination of the native structure of casein micelles continues to be extremely challenging. The biological functions of caseins, such as their chaperone activity, are determined by their composition and flexible conformation and by how the casein polypeptide chains interact with each other. These same properties determine how caseins behave in the manufacture of many dairy products and how they can be used as functional ingredients in other foods.
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Affiliation(s)
- C Holt
- Institute of Molecular, Cell and Systems Biology, School of Life Sciences, University of Glasgow, Glasgow G12 8QQ, United Kingdom.
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Canale C, Seghezza S, Vilasi S, Carrotta R, Bulone D, Diaspro A, San Biagio PL, Dante S. Different effects of Alzheimer's peptide Aβ(1-40) oligomers and fibrils on supported lipid membranes. Biophys Chem 2013; 182:23-9. [PMID: 23998637 DOI: 10.1016/j.bpc.2013.07.010] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2013] [Revised: 07/18/2013] [Accepted: 07/19/2013] [Indexed: 10/26/2022]
Abstract
Beta-amyloid (1-40) is one of the two most abundant species of amyloid-beta peptides present as fibrils in the extracellular senile plaques in the brain of Alzheimer's patients. Recently, the molecular aggregates constituting the early stage of fibril formation, i.e., oligomers and protofibrils, have been investigated as the main responsible for amyloid-beta cytotoxic effect. The molecular mechanism leading to neurodegeneration is still under debate, and it is common opinion that it may reside in the interaction between amyloid species and the neural membrane. In this investigation Atomic Force Microscopy and spectroscopy have been used to understand how structural (and mechanical) properties of POPC/POPS lipid bilayers, simulating the phospholipid composition and negative net charge of neuritic cell membranes, are influenced by the interaction with Aβ(1-40), in different stages of the peptide aggregation. Substantial differences in the damage caused to the lipid bilayers have been observed, confirming the toxic effect exerted especially by Aβ(1-40) prefibrillar oligomers.
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Affiliation(s)
- Claudio Canale
- Nanophysics, Istituto Italiano di Tecnologia, Via Morego 30, 16163 Genova, Italy
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40
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Sharoar MG, Shahnawaz M, Islam MI, Ramasamy VS, Shin SY, Park IS. The inhibitory effects of Escherichia coli maltose binding protein on β-amyloid aggregation and cytotoxicity. Arch Biochem Biophys 2013; 538:41-8. [PMID: 23948569 DOI: 10.1016/j.abb.2013.08.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2013] [Revised: 07/29/2013] [Accepted: 08/02/2013] [Indexed: 01/14/2023]
Abstract
The aggregation of β-amyloid (Aβ) peptide from its monomeric to its fibrillar form importantly contributes to the development of Alzheimer's disease. Here, we investigated the effects of Escherichia coli maltose binding protein (MBP), which has been previously used as a fusion protein, on Aβ42 fibrillization, in order to improve understanding of the self-assembly process and the cytotoxic mechanism of Aβ42. MBP, at a sub-stoichiometric ratio with respect to Aβ42, was found to have chaperone-like inhibitory effects on β-sheet fibril formation, due to the accumulation of Aβ42 aggregates by sequestration of active Aβ42 species as Aβ42-MBP complexes. Furthermore, MBP increased the lag time of Aβ42 polymerization, decreased the growth rate of fibril extension, and suppressed Aβ42 mediated toxicity in human neuroblastoma SH-SY5Y cells. It appears that MBP decreases the active concentration of Aβ42 by sequestering it as Aβ42-MBP complex, and that this sequestration suppresses ongoing nucleation and retards the growth rate of Aβ42 species required for fibril formation. We speculate that inhibition of the growth rate of potent Aβ42 species by MBP suppresses Aβ42-mediated toxicity in SH-SY5Y cells.
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Affiliation(s)
- Md Golam Sharoar
- Department of Bio-Materials Engineering, Chosun University, Gwanju 501-759, Republic of Korea; Department of Genetic Engineering and Biotechnology, University of Rajshahi, Rajshahi 6205, Bangladesh
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Affiliation(s)
- Amy R. Wyatt
- School of Biological Sciences, University of Wollongong, Wollongong, New South Wales 2522, Australia;
- Department of Chemistry, University of Cambridge, Cambridge CB2 1EW, United Kingdom
| | - Justin J. Yerbury
- School of Biological Sciences, University of Wollongong, Wollongong, New South Wales 2522, Australia;
| | - Heath Ecroyd
- School of Biological Sciences, University of Wollongong, Wollongong, New South Wales 2522, Australia;
| | - Mark R. Wilson
- School of Biological Sciences, University of Wollongong, Wollongong, New South Wales 2522, Australia;
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42
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A preparation of cow's late colostrum fraction containing αs1-casein promoted the proliferation of cultured rat intestinal IEC-6 epithelial cells. Biosci Biotechnol Biochem 2013; 77:992-7. [PMID: 23649260 DOI: 10.1271/bbb.120942] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Colostrum is a complex mixture of bioactives that promotes neonate growth. Recently, we have found by in vivo study that skimmed, sterilized, and concentrated bovine late colostrum (SCBLC), obtained from a Holstein herd on days 6-7 after parturition, had an ability to maintain intestinal integrity. In the present study we investigated effects of SCBLC on rat intestinal IEC-6 cell proliferation in vitro. A fraction containing αs1-casein was found to have a robust stimulation effect as compared to other protein fractions from SCBLC and even the αs1-casein fraction from milk from other Holstein herds. Furthermore, the SCBLC αs1-casein molecule demonstrated not only slightly slower mobility on both SDS- and native-PAGE than other bovine milk αs1-caseins, but also a peculiar conformation reminiscent of moltenglobule in the circular dichroism spectrum. These findings may be of relevant to the competence of SCBLC to preserve intestinal integrity.
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Carrotta R, Vilasi S, Librizzi F, Martorana V, Bulone D, San Biagio PL. α-Casein inhibition mechanism in concanavalin A aggregation process. J Phys Chem B 2012; 116:14700-7. [PMID: 23171317 DOI: 10.1021/jp307417x] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The inhibition of the aggregation in protein solutions is currently a subject of great interest in many research fields, from the study of protein-misfolding related diseases to pharmaceutics, biotechnology, and food science. α(s1)-Casein, one of the four types of caseins, which are the largest protein component of bovine milk, has been found to hinder the aggregation process of several proteins, including the amyloid β-peptide, involved in Alzheimer's disease. To shed light into the mechanisms by which casein exerts this chaperon-like protective action, we studied its effect on the different steps of the aggregation process of concanavalin A, by means of both static and dynamic light scattering, thioflavin T and ANS fluorescence, circular dichroism, and atomic force microscopy. Our results show that casein has a poor effect on the first step of the process leading to the formation of amyloid-like structures. On the contrary, it has a marked effect on the second step of the process, ascribable to clusters condensation and compaction, up to the formation of very large aggregates. Such an effect requires a molar ratio of casein larger than that necessary to inhibit the fibrillogenesis of the amyloid β-peptide, thus, suggesting a different mechanism of interaction of casein, depending on both conformational properties and relative size of the aggregating molecules.
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Affiliation(s)
- Rita Carrotta
- Institute of Biophysics, The National Research Council, Via Ugo La Malfa 153, 90146 Palermo, Italy.
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44
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Jameson LP, Smith NW, Dzyuba SV. Dye-binding assays for evaluation of the effects of small molecule inhibitors on amyloid (aβ) self-assembly. ACS Chem Neurosci 2012; 3:807-19. [PMID: 23173064 DOI: 10.1021/cn300076x] [Citation(s) in RCA: 106] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2012] [Accepted: 08/06/2012] [Indexed: 01/07/2023] Open
Abstract
Dye-binding assays, such as those utilizing Congo red and thioflavin T, are among the most widely used tools to probe the aggregation of amyloidogenic biomolecules and for the evaluation of small molecule inhibitors of amyloid aggregation and fibrillization. A number of recent reports have indicated that these dye-binding assays could be prone to false positive effects when assessing inhibitors' potential toward Aβ peptides, species involved in Alzheimer's disease. Specifically, this review focuses on the application of thioflavin T for determining the efficiency of small molecule inhibitors of Aβ aggregation and addresses potential reasons that might be associated with the false positive effects in an effort to increase reliability of dye-binding assays.
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Affiliation(s)
- Laramie P. Jameson
- Department of Chemistry, Texas Christian University, Fort Worth, Texas 76129, United States
| | - Nicholas W. Smith
- Department of Chemistry, Texas Christian University, Fort Worth, Texas 76129, United States
| | - Sergei V. Dzyuba
- Department of Chemistry, Texas Christian University, Fort Worth, Texas 76129, United States
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