51
|
Solís V, Palopoli C, Daier V, Rivière E, Collin F, Moreno DM, Hureau C, Signorella S. Tuning the Mn II2/Mn III2 redox cycle of a phenoxo-bridged diMn catalase mimic with terminal carboxylate donors. J Inorg Biochem 2018; 182:29-36. [PMID: 29407867 DOI: 10.1016/j.jinorgbio.2018.01.013] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2017] [Revised: 01/14/2018] [Accepted: 01/21/2018] [Indexed: 11/27/2022]
Abstract
A new phenoxo-bridged diMnIII complex, Na[Mn2L(OH)2(H2O)2]·5H2O (1), obtained with the ligand L5- = 5‑methyl‑2‑hydroxo‑1,3‑xylene‑α,α‑diamine‑N,N,N',N'‑tetraacetato, has been prepared and characterized. Mass spectrometry, conductivity, UV-visible, EPR and 1H NMR spectroscopic studies showed that the complex exists in solution as a monoanionic diMnIII complex. Complex 1 catalyzes H2O2 disproportionation with second-order rate constant kcat = 305(9) M-1 min-1 and without a time-lag phase. Based on spectroscopic results, the catalase activity of complex 1 in methanol involves a MnIII2/MnII2 redox cycle, which distinguishes this catalyst from other phenoxo-bridged diMn complexes that cycle between MnIIMnIII/MnIIIMnIV species. Addition of base stabilizes the catalyst, restrains demetallation during catalysis and causes moderate enhancement of catalase activity. The terminal carboxylate donors of 1 not only contribute as internal bases to assist deprotonation of H2O2 but also favor the formation of active homovalent diMn species, just as observed for the enzyme.
Collapse
|
52
|
Pocinho A, Duhayon C, Gras E, Hureau C. Crystal structure of catena-poly[[[dichloridocopper(II)]-{μ- tert-butyl N-methyl- N-[4-(6-{[4-(pyridin-2-yl-κ N)-1 H-1,2,3-triazol-1-yl-κ N
3]methyl}-1,3-benzothiazol-2-yl)phenyl]carbamato}] acetonitrile monosolvate]. Acta Crystallogr E Crystallogr Commun 2018; 74:158-162. [PMID: 29850044 PMCID: PMC5956327 DOI: 10.1107/s2056989018000488] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2017] [Accepted: 01/08/2018] [Indexed: 11/23/2022]
Abstract
The title coordination polymer was obtained by combining an aqueous solution of copper(II) dichloride with the ligand {tert-butylmethyl[4-(6-{[4-(pyridin-2-yl-)1H-1,2,3-triazol-1-yl]methyl}-1,3-benzothiazol-2-yl)phenyl]carbamate in acetonitrile. In the title coordination polymer, {[CuCl2(C27H26N6O2S)]·CH3CN}n, the copper(II) ion is fivefold coordinated, with an almost perfect square-pyramidal coordination sphere. In the equatorial plane, it is ligated to a pyridine N atom and an N atom of the triazole unit and to two Cl− ions, while the apical position is occupied by the carbonyl O atom of the tert-butyl carbamate group. In the crystal, the polymer chains propagate in the [11-1] direction, with the acetonitrile solvent molecules linked to the chain by C—H⋯N hydrogen bonds. The chains are linked by C—H⋯Cl hydrogen bonds forming sheets parallel to the plane (011). The crystal packing is further consolidated by C—H⋯π interactions and offset π–π stacking interactions [intercentroid distance = 3.6805 (15) Å], forming a three-dimensional supramolecular structure.
Collapse
|
53
|
Cheignon C, Collin F, Faller P, Hureau C. Is ascorbate Dr Jekyll or Mr Hyde in the Cu(Aβ) mediated oxidative stress linked to Alzheimer's disease? Dalton Trans 2018; 45:12627-31. [PMID: 27264439 PMCID: PMC5714186 DOI: 10.1039/c6dt01979j] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Evaluation of the pro versus antioxidant activity of ascorbate regarding Cu(Aβ) induced reactive oxygen species production in the context of Alzheimer’s disease shows that a protective activity can only be observed at high ascorbate concentration for exogenous molecules but not for the amyloid-β peptide itself.
Collapse
|
54
|
Borghesani V, Alies B, Hureau C. Front Cover: Cu
II
Binding to Various Forms of Amyloid‐β Peptides: Are They Friends or Foes? (Eur. J. Inorg. Chem. 1/2018). Eur J Inorg Chem 2018. [DOI: 10.1002/ejic.201701373] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
55
|
Borghesani V, Alies B, Hureau C. Cu(II) binding to various forms of amyloid-β peptides. Are they friends or foes? Eur J Inorg Chem 2018; 2018:7-15. [PMID: 30186035 PMCID: PMC6120674 DOI: 10.1002/ejic.201700776] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2017] [Indexed: 01/25/2023]
Abstract
In the present micro-review, we describe the Cu(II) binding to several forms of amyloid-β peptides, the peptides involved in Alzheimer's disease. It has indeed been shown that in addition to the "full-length" peptide originating from the precursor protein after cleavage at position 1, several other shorter peptides do exist in large proportion and may be involved in the disease as well. Cu(II) binding to amyloid-β peptides is one of the key interactions that impact both the aggregating properties of the amyloid peptides and the Reactive Oxygen Species (ROS) production, two events linked to the etiology of the disease. Binding sites and affinity are described in correlation with Cu(II) induced ROS formation and Cu(II) altered aggregation, for amyloid peptides starting at position 1, 3, 4, 11 and for the corresponding pyroglutamate forms when they could be obtained (i.e. for peptides cleaved at positions 3 and 11). It appears that the current paradigm which points out a toxic role of the Cu(II) - amyloid-β interaction might well be shifted towards a possible protective role when the peptides considered are the N-terminally truncated ones.
Collapse
|
56
|
Atrián-Blasco E, Santoro A, Pountney DL, Meloni G, Hureau C, Faller P. Chemistry of mammalian metallothioneins and their interaction with amyloidogenic peptides and proteins. Chem Soc Rev 2017; 46:7683-7693. [PMID: 29114657 PMCID: PMC5728347 DOI: 10.1039/c7cs00448f] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Cu and Zn ions are essential in most living beings. Their metabolism is critical for health and mis-metabolism can be lethal. In the last two decades, a large body of evidence has reported the role of copper, zinc and iron, and oxidative stress in several neurodegenerative diseases like Alzheimer's, Parkinson's, prion diseases, etc. To what extent this mis-metabolism is causative or a consequence of these diseases is still a matter of research. In this context metallothioneins (MTs) appear to play a central gate-keeper role in controlling aberrant metal-protein interactions. MTs are small proteins that can bind high amounts of Zn(ii) and Cu(i) ions in metal-cluster arrangements via their cysteine thiolates. Moreover, MTs are well known antioxidants. The present tutorial outlines the chemistry underlying the interconnection between copper(i/ii) and zinc(ii) coordination to amyloidogenic proteins and MTs, and their redox properties in generation and/or silencing reactive oxygen species (overproduced in oxidative stress) and other reactants. These studies have revealed the coordination chemistry involved in neurodegenerative diseases and the interactions between MTs and amyloidogenic protein metal-complexes (like amyloid-β, α-synuclein and prion-protein). Overall, the protective role of MTs in neurodegenerative processes is emerging, serving as a foundation for exploring MT chemistry as inspiration for therapeutic approaches.
Collapse
|
57
|
Borghesani V, Alies B, Hureau C. Cu
II
Binding to Various Forms of Amyloid‐β Peptides: Are They Friends or Foes? Eur J Inorg Chem 2017. [DOI: 10.1002/ejic.201701374] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
|
58
|
Conte-Daban A, Boff B, Candido Matias A, Aparicio CNM, Gateau C, Lebrun C, Cerchiaro G, Kieffer I, Sayen S, Guillon E, Delangle P, Hureau C. A Trishistidine Pseudopeptide with Ability to Remove Both Cu Ι and Cu ΙΙ from the Amyloid-β Peptide and to Stop the Associated ROS Formation. Chemistry 2017; 23:17078-17088. [PMID: 28846165 PMCID: PMC5714062 DOI: 10.1002/chem.201703429] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2017] [Indexed: 01/08/2023]
Abstract
The pseudopeptide L, derived from a nitrilotriacetic acid scaffold and functionalized with three histidine moieties, is reminiscent of the amino acid side chains encountered in the Alzheimer's peptide (Aβ). Its synthesis and coordination properties for CuΙ and CuΙΙ are described. L efficiently complex CuΙΙ in a square-planar geometry involving three imidazole nitrogen atoms and an amidate-Cu bond. By contrast, CuΙ is coordinated in a tetrahedral environment. The redox behavior is irreversible and follows an ECEC mechanism in accordance with the very different environments of the two redox states of the Cu center. This is in line with the observed resistance of the CuΙ complex to oxidation by oxygen and the CuΙΙ complex reduction by ascorbate. The affinities of L for CuΙΙ and CuΙ at physiological pH are larger than that reported for the Aβ peptide. Therefore, due to its peculiar Cu coordination properties, the ligand L is able to target both redox states of Cu, redox silence them and prevent reactive oxygen species production by the CuAβ complex. Because reactive oxygen species contribute to the oxidative stress, a key issue in Alzheimer's disease, this ligand thus represents a new strategy in the long route of finding molecular concepts for fighting Alzheimer's disease.
Collapse
|
59
|
Gonzalez P, Vileno B, Bossak K, El Khoury Y, Hellwig P, Bal W, Hureau C, Faller P. Cu(II) Binding to the Peptide Ala-His-His, a Chimera of the Canonical Cu(II)-Binding Motifs Xxx-His and Xxx-Zzz-His. Inorg Chem 2017; 56:14870-14879. [DOI: 10.1021/acs.inorgchem.7b01996] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
60
|
Cheignon C, Faller P, Testemale D, Hureau C, Collin F. Metal-catalyzed oxidation of Aβ and the resulting reorganization of Cu binding sites promote ROS production. Metallomics 2017; 8:1081-1089. [PMID: 27730227 PMCID: PMC5714184 DOI: 10.1039/c6mt00150e] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In the context of Alzheimer’s disease (AD), the production of HO• by copper–amyloid beta (Aβ) in the presence of ascorbate is known to be deleterious for the Aβ peptide itself and also for the surrounding molecules, thus establishing a direct link between AD and oxidative stress. The metal-catalyzed oxidation (MCO) of Aβ primarily targets the residues involved in copper coordination during HO• production. In the present work, we demonstrate that the oxidative damage undergone by Aβ during MCO lead to a change in copper coordination, with enhanced catalytic properties that increases the rates of ascorbate consumption and HO• production, and the amount of HO• released by the system. This phenomenon is observed after the peptide has been sufficiently oxidized.
Collapse
|
61
|
Atrián-Blasco E, Conte-Daban A, Hureau C. Mutual interference of Cu and Zn ions in Alzheimer's disease: perspectives at the molecular level. Dalton Trans 2017; 46:12750-12759. [PMID: 28937157 PMCID: PMC5656098 DOI: 10.1039/c7dt01344b] [Citation(s) in RCA: 63] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2017] [Accepted: 06/22/2017] [Indexed: 12/26/2022]
Abstract
While metal ions such as copper and zinc are essential in biology, they are also linked to several amyloid-related diseases, including Alzheimer's disease (AD). Zinc and copper can indeed modify the aggregation pathways of the amyloid-β (Aβ) peptide, the key component encountered in AD. In addition, the redox active copper ions do produce Reactive Oxygen Species (ROS) when bound to the Aβ peptide. While Cu(i) or Cu(ii) or Zn(ii) coordination to the Aβ has been extensively studied in the last ten years, characterization of hetero-bimetallic Aβ complexes is still scarce. This is also true for the metal induced Aβ aggregation and ROS production, for which studies on the mutual influence of the copper and zinc ions are currently appearing. Last but not least, zinc can strongly interfere in therapeutic approaches relying on copper detoxification. This will be exemplified with a biological lead, namely metallothioneins, and with synthetic ligands.
Collapse
|
62
|
Cheignon C, Jones M, Atrián-Blasco E, Kieffer I, Faller P, Collin F, Hureau C. Identification of key structural features of the elusive Cu-Aβ complex that generates ROS in Alzheimer's disease. Chem Sci 2017; 8:5107-5118. [PMID: 28970897 PMCID: PMC5613283 DOI: 10.1039/c7sc00809k] [Citation(s) in RCA: 99] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2017] [Accepted: 04/29/2017] [Indexed: 12/16/2022] Open
Abstract
Oxidative stress is linked to the etiology of Alzheimer's disease (AD), the most common cause of dementia in the elderly. Redox active metal ions such as copper catalyze the production of Reactive Oxygen Species (ROS) when bound to the amyloid-β (Aβ) peptide encountered in AD. We propose that this reaction proceeds through a low-populated Cu-Aβ state, denoted the "catalytic in-between state" (CIBS), which is in equilibrium with the resting state (RS) of both Cu(i)-Aβ and Cu(ii)-Aβ. The nature of this CIBS is investigated in the present work. We report the use of complementary spectroscopic methods (X-ray absorption spectroscopy, EPR and NMR) to characterize the binding of Cu to a wide series of modified peptides in the RS. ROS production by the resulting Cu-peptide complexes was evaluated using fluorescence and UV-vis based methods and led to the identification of the amino acid residues involved in the Cu-Aβ CIBS species. In addition, a possible mechanism by which the ROS are produced is also proposed. These two main results are expected to affect the current vision of the ROS production mechanism by Cu-Aβ but also in other diseases involving amyloidogenic peptides with weakly structured copper binding sites.
Collapse
|
63
|
Conte-Daban A, Borghesani V, Sayen S, Guillon E, Journaux Y, Gontard G, Lisnard L, Hureau C. Link between Affinity and Cu(II) Binding Sites to Amyloid-β Peptides Evaluated by a New Water-Soluble UV-Visible Ratiometric Dye with a Moderate Cu(II) Affinity. Anal Chem 2017; 89:2155-2162. [PMID: 28208266 PMCID: PMC5714188 DOI: 10.1021/acs.analchem.6b04979] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Being able to easily determine the Cu(II) affinity for biomolecules of moderate affinity is important. Such biomolecules include amyloidogenic peptides, such as the well-known amyloid-β peptide involved in Alzheimer's disease. Here, we report the synthesis of a new water-soluble ratiometric Cu(II) dye with a moderate affinity (109 M-1 at pH 7.1) and the characterizations of the Cu(II) corresponding complex by X-ray crystallography, EPR, and XAS spectroscopic methods. UV-vis competition was performed on the Aβ peptide as well as on a wide series of modified peptides, leading to an affinity value of 1.6 × 109 M-1 at pH 7.1 for the Aβ peptide and to a coordination model for the Cu(II) site within the Aβ peptide that agrees with the one mostly accepted currently.
Collapse
|
64
|
Palopoli C, Gómez G, Foi A, Doctorovich F, Mallet-Ladeira S, Hureau C, Signorella S. Dimerization, redox properties and antioxidant activity of two manganese(III) complexes of difluoro- and dichloro-substituted Schiff-base ligands. J Inorg Biochem 2016; 167:49-59. [PMID: 27907863 DOI: 10.1016/j.jinorgbio.2016.11.019] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2016] [Revised: 11/08/2016] [Accepted: 11/16/2016] [Indexed: 11/16/2022]
Abstract
Two mononuclear MnIII complexes [Mn(3,5-F2salpn)(H2O)2][B(C6H5)4]·2H2O (1·2H2O) and [Mn(3,5-Cl2salpn)(OAc)(H2O)]·H2O (2·H2O), where H2salpn=1,3-bis(salicylidenamino)propane, have been prepared and characterized. The crystal structure of 1·H2O shows that this complex forms μ-aqua dimers with a short Mn⋯Mn distance of 4.93Å. Under anaerobic conditions, the two complexes are stable in solution and possess trans-diaxial symmetry with the tetradentate Schiff base ligand symmetrically arranged in the equatorial plane. When left in air, these complexes slowly dimerize to yield high-valent [MnIV2(3,5-X2-salpn)2(μ-O)2] in which each X2-salpn ligand wraps the two Mn ions. This process is favored in basic medium where the deprotonation of the bound water molecule is concomitant with air oxidation. The two complexes catalyze the dismutation of superoxide (superoxide dismutase (SOD) activity) and peroxide (catalase (CAT) activity) in basic medium. The phenyl-ring substituents play an important role on the CAT reaction but have little effect on SOD activity. Kinetics and spectroscopic results indicate that 1 and 2 catalyze H2O2 disproportionation through a cycle involving MnIII2 and MnIV2 dimers, unlike related complexes with a more rigid and smaller chelate ring, which employ MnIII/MnVO monomers.
Collapse
|
65
|
Conte-Daban A, Day A, Faller P, Hureau C. How Zn can impede Cu detoxification by chelating agents in Alzheimer's disease: a proof-of-concept study. Dalton Trans 2016; 45:15671-15678. [PMID: 27711738 PMCID: PMC5123634 DOI: 10.1039/c6dt02308h] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2016] [Accepted: 08/23/2016] [Indexed: 01/31/2023]
Abstract
The role of Cu and Zn ions in Alzheimer's disease is linked to the consequences of their coordination to the amyloid-β (Aβ) peptide, i.e. to the modulation of Aβ aggregation and to the production of Reactive Oxygen Species (ROS), two central events of the so-called amyloid cascade. The role of both ions in Aβ aggregation is still controversial. Conversely the higher toxicity of the redox competent Cu ions (compared to the redox inert Zn ions) in ROS production is acknowledged. Thus the Cu ions can be considered as the main therapeutic target. Because Zn ions are present in higher quantity than Cu ions in the synaptic cleft, they can prevent detoxification of Cu by chelators unless they have an unusually high Cu over Zn selectivity. We describe a proof-of-concept study where the role of Zn on the metal swap reaction between two prototypical ligands and the Cu(Aβ) species has been investigated by several complementary spectroscopic techniques (UV-Vis, EPR and XANES). The first ligand has a higher Cu over Zn selectivity relative to the one of Aβ peptide while the second one exhibits a classical Cu over Zn selectivity. How Zn impacts the effect of the ligands on Cu-induced ROS production and Aβ aggregation is also reported.
Collapse
|
66
|
Alies B, Conte-Daban A, Sayen S, Collin F, Kieffer I, Guillon E, Faller P, Hureau C. Zinc(II) Binding Site to the Amyloid-β Peptide: Insights from Spectroscopic Studies with a Wide Series of Modified Peptides. Inorg Chem 2016; 55:10499-10509. [PMID: 27665863 PMCID: PMC5069684 DOI: 10.1021/acs.inorgchem.6b01733] [Citation(s) in RCA: 67] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
The Zn(II) ion has been linked to Alzheimer's disease (AD) due to its ability to modulate the aggregating properties of the amyloid-β (Aβ) peptide, where Aβ aggregation is a central event in the etiology of the disease. Delineating Zn(II) binding properties to Aβ is thus a prerequisite to better grasp its potential role in AD. Because of (i) the flexibility of the Aβ peptide, (ii) the multiplicity of anchoring sites, and (iii) the silent nature of the Zn(II) ion in most classical spectroscopies, this is a difficult task. To overcome these difficulties, we have investigated the impact of peptide alterations (mutations, N-terminal acetylation) on the Zn(Aβ) X-ray absorption spectroscopy fingerprint and on the Zn(II)-induced modifications of the Aβ peptides' NMR signatures. We propose a tetrahedrally bound Zn(II) ion, in which the coordination sphere is made by two His residues and two carboxylate side chains. Equilibria between equivalent ligands for one Zn(II) binding position have also been observed, the predominant site being made by the side chains of His6, His13 or His14, Glu11, and Asp1 or Glu3 or Asp7, with a slight preference for Asp1.
Collapse
|
67
|
Hoarau M, Malbert Y, Irague R, Hureau C, Faller P, Gras E, André I, Remaud-Siméon M. A Robust and Efficient Production and Purification Procedure of Recombinant Alzheimers Disease Methionine-Modified Amyloid-β Peptides. PLoS One 2016; 11:e0161209. [PMID: 27532547 PMCID: PMC4988814 DOI: 10.1371/journal.pone.0161209] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2016] [Accepted: 08/01/2016] [Indexed: 01/29/2023] Open
Abstract
An improved production and purification method for Alzheimer’s disease related methionine-modified amyloid-β 1–40 and 1–42 peptides is proposed, taking advantage of the formation of inclusion body in Escherichia coli. A Thioflavin-S assay was set-up to evaluate inclusion body formation during growth and optimize culture conditions for amyloid-β peptides production. A simple and fast purification protocol including first the isolation of the inclusion bodies and second, two cycles of high pH denaturation/ neutralization combined with an ultrafiltration step on 30-kDa cut-off membrane was established. Special attention was paid to purity monitoring based on a rational combination of UV spectrophotometry and SDS-PAGE analyses at the various stages of the process. It revealed that this chromatography-free protocol affords good yield of high quality peptides in term of purity. The resulting peptides were fully characterized and are appropriate models for highly reproducible in vitro aggregation studies.
Collapse
|
68
|
Reybier K, Ayala S, Alies B, Rodrigues JV, Bustos Rodriguez S, La Penna G, Collin F, Gomes CM, Hureau C, Faller P. Free Superoxide is an Intermediate in the Production of H2O2 by Copper(I)-Aβ Peptide and O2. Angew Chem Int Ed Engl 2015; 55:1085-9. [PMID: 26629876 DOI: 10.1002/anie.201508597] [Citation(s) in RCA: 78] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2015] [Indexed: 11/06/2022]
Abstract
Oxidative stress is considered as an important factor and an early event in the etiology of Alzheimer's disease (AD). Cu bound to the peptide amyloid-β (Aβ) is found in AD brains, and Cu-Aβ could contribute to this oxidative stress, as it is able to produce in vitro H2O2 and HO˙ in the presence of oxygen and biological reducing agents such as ascorbate. The mechanism of Cu-Aβ-catalyzed H2O2 production is however not known, although it was proposed that H2O2 is directly formed from O2 via a 2-electron process. Here, we implement an electrochemical setup and use the specificity of superoxide dismutase-1 (SOD1) to show, for the first time, that H2O2 production by Cu-Aβ in the presence of ascorbate occurs mainly via a free O2˙(-) intermediate. This finding radically changes the view on the catalytic mechanism of H2O2 production by Cu-Aβ, and opens the possibility that Cu-Aβ-catalyzed O2˙(-) contributes to oxidative stress in AD, and hence may be of interest.
Collapse
|
69
|
Reybier K, Ayala S, Alies B, Rodrigues JV, Bustos Rodriguez S, La Penna G, Collin F, Gomes CM, Hureau C, Faller P. Free Superoxide is an Intermediate in the Production of H
2
O
2
by Copper(I)‐Aβ Peptide and O
2. Angew Chem Int Ed Engl 2015. [DOI: 10.1002/ange.201508597] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
|
70
|
De Ricco R, Valensin D, Dell'Acqua S, Casella L, Hureau C, Faller P. Copper(I/II), α/β-Synuclein and Amyloid-β: Menage à Trois? Chembiochem 2015; 16:2319-28. [PMID: 26338312 DOI: 10.1002/cbic.201500425] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2015] [Indexed: 12/12/2022]
Abstract
Copper binding to α-synuclein (aS) and to amyloid-β (Ab) has been connected to Parkinson's and Alzheimer's disease (AD), respectively, because Cu ions can modulate the peptide aggregation, and these Cu ⋅ peptide complexes can catalyse the production of reactive oxygen species (ROS). In a significant proportion of AD brains, aggregation of aS and Ab has been detected, and it was proposed that Ab and aS interact with each other. Thus, we investigated the potential interactions of Ab and aS through their binding of copper(I) and copper(II). Additionally, β-synuclein (bS) was investigated, due to its additional methionine residue, a potential Cu(I) ligand. We found that: 1) the peptides containing the Cu-binding domains Ab1-16, aS1-15 and bS1-15 have similar affinities towards Cu(II) and towards Cu(I), with Ab1-16 being slightly stronger, 2) in the case of Cu(I), the additional Met residue in bS1-15 increased the affinity slightly, 3) the exchange of Cu(I/II) between the two peptides is rapid (≤ ms), 4) a/bS1-15 and Ab1-16 form a heterodimeric complex with Cu(II), 5) Cu(I) probably promotes a transient ternary complex, 6) the different Cu(I/II) coordination of Ab1-16, aS1-15 and bS1-15 impacts the capacity to produce ROS and to oxidise catechol, and 7) when Ab1-16, aS1-15 and Cu are present, the ROS production more closely resembles that by Ab1-16. The work gives insights into the coordination chemistry of these related peptides, and the relevance of coordination differences, the ternary complex and ROS production are discussed.
Collapse
|
71
|
De Ricco R, Valensin D, Dell’Acqua S, Casella L, Dorlet P, Faller P, Hureau C. Remote His50 Acts as a Coordination Switch in the High-Affinity N-Terminal Centered Copper(II) Site of α-Synuclein. Inorg Chem 2015; 54:4744-51. [DOI: 10.1021/acs.inorgchem.5b00120] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
|
72
|
Atrián-Blasco E, Cerrada E, Conte-Daban A, Testemale D, Faller P, Laguna M, Hureau C. Copper(I) targeting in the Alzheimer's disease context: a first example using the biocompatible PTA ligand. Metallomics 2015; 7:1229-32. [PMID: 25926057 DOI: 10.1039/c5mt00077g] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Copper(I) coordinating ligands in the Alzheimer's disease context have remained unexplored, despite the biological relevance of this redox state of the copper ion. Here, we show that the PTA ligand can remove copper from Aβ, prevent reactive oxygen species production and oligomer formation, two deleterious events in the disease's etiology.
Collapse
|
73
|
Ledesma GN, Eury H, Anxolabéhère-Mallart E, Hureau C, Signorella SR. A new mononuclear manganese(III) complex of an unsymmetrical hexadentate N3O3 ligand exhibiting superoxide dismutase and catalase-like activity: synthesis, characterization, properties and kinetics studies. J Inorg Biochem 2015; 146:69-76. [PMID: 25771435 DOI: 10.1016/j.jinorgbio.2015.02.012] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2014] [Revised: 02/20/2015] [Accepted: 02/20/2015] [Indexed: 11/28/2022]
Abstract
A mononuclear Mn(III) complex MnL·4H2O (H3L=1-[N-(2-pyridylmethyl),N-(2-hydroxybenzyl)amino]-3-[N'-(2-hydroxybenzyl),N'-(4-methylbenzyl)amino]propan-2-ol) has been prepared and characterized. This complex catalyzes the dismutation of superoxide efficiently, with catalytic rate constant kcat=1.7×10(6)M(-1)s(-1) and IC50 1.26μM, obtained through the nitro blue tetrazolium photoreduction inhibition superoxide dismutase assay, in aqueous solution of pH7.8. MnL is also able to disproportionate more than 300 equivalents of H2O2 in CH3CN, with initial rate of H2O2 decomposition given by ri=kcat [MnL](2) [H2O2] and kcat=1.32(2)mM(-2)min(-1). The accessibility of the Mn(IV) state (E(p)=0.53V vs. saturated calomel electrode), suggests MnL employs a high-valent catalytic cycle to decompose O2(-) and H2O2.
Collapse
|
74
|
Noël S, Bustos Rodriguez S, Sayen S, Guillon E, Faller P, Hureau C. Use of a new water-soluble Zn sensor to determine Zn affinity for the amyloid-β peptide and relevant mutants. Metallomics 2015; 6:1220-2. [PMID: 24652294 DOI: 10.1039/c4mt00016a] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Evaluation of Zn affinity for the amyloid-β peptide involved in Alzheimer's disease and its modified counterparts is reported. This was made possible by the use of a new water-soluble chelator, the properties of which have also been described. Changes in the peptide sequence that impact Zn affinity are briefly discussed.
Collapse
|
75
|
Alies B, Eury H, Essassi EM, Pratviel G, Hureau C, Faller P. Concept for Simultaneous and Specific in Situ Monitoring of Amyloid Oligomers and Fibrils via Förster Resonance Energy Transfer. Anal Chem 2014; 86:11877-82. [DOI: 10.1021/ac503509g] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
|