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Feng B, Wang Z, Liu T, Jin R, Wang S, Wang W, Xiao G, Zhou Z. Methionine oxidation accelerates the aggregation and enhances the neurotoxicity of the D178N variant of the human prion protein. Biochim Biophys Acta Mol Basis Dis 2014; 1842:2345-56. [PMID: 25281825 DOI: 10.1016/j.bbadis.2014.09.012] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2014] [Revised: 08/27/2014] [Accepted: 09/24/2014] [Indexed: 12/30/2022]
Abstract
The D178N mutation of the prion protein (PrP) results in the hereditary prion disease fatal familial insomnia (FFI). Little is known regarding the effects of methionine oxidation on the pathogenesis of D178N-associated FFI. In the present study, we found that the D178N variant was more susceptible to oxidation than wild-type PrP, as indicated by reverse-phase high performance liquid chromatography (RP-HPLC) and mass spectrometry (MS) analysis. Circular dichroism (CD), differential scanning calorimetry (DSC), thioflavin T (ThT) binding assay studies demonstrated that methionine oxidation decreased the structural stability of the D178N variant, and the oxidized D178N variant exhibited a greater propensity to form β-sheet-rich oligomers and aggregates. Moreover, these aggregates of oxidized D178N PrP were more resistant to proteinase K (PK) digestion. Additionally, using fluorescence confocal microscopy, we detected a high degree of aggregation in D178N-transfected Neuro-2a (N2a) cells after treatment with hydrogen peroxide (H2O2). Furthermore, the oxidation and consequent aggregation of the D178N variant induced greater apoptosis of N2a cells, as monitored using flow cytometry. Collectively, these observations suggest that methionine oxidation accelerates the aggregation and enhances the neurotoxicity of the D178N variant, possibly providing direct evidence to link the pathogenesis of D178N-associated FFI with methionine oxidation.
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Affiliation(s)
- Boya Feng
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, Hubei 430071, China; University of the Chinese Academy of Sciences, Beijing 100039, China
| | - Zonglin Wang
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, Hubei 430071, China; University of the Chinese Academy of Sciences, Beijing 100039, China
| | - Ting Liu
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, Hubei 430071, China; University of the Chinese Academy of Sciences, Beijing 100039, China
| | - Rui Jin
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, Hubei 430071, China; University of the Chinese Academy of Sciences, Beijing 100039, China
| | - Shaobo Wang
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, Hubei 430071, China; University of the Chinese Academy of Sciences, Beijing 100039, China
| | - Wei Wang
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, Hubei 430071, China; University of the Chinese Academy of Sciences, Beijing 100039, China
| | - Gengfu Xiao
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, Hubei 430071, China; University of the Chinese Academy of Sciences, Beijing 100039, China.
| | - Zheng Zhou
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, Hubei 430071, China; University of the Chinese Academy of Sciences, Beijing 100039, China.
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Zijlstra N, Claessens MMAE, Blum C, Subramaniam V. Elucidating the aggregation number of dopamine-induced α-synuclein oligomeric assemblies. Biophys J 2014; 106:440-6. [PMID: 24461019 DOI: 10.1016/j.bpj.2013.12.009] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2013] [Revised: 11/29/2013] [Accepted: 12/03/2013] [Indexed: 11/26/2022] Open
Abstract
Conventional methods to determine the aggregation number, that is, the number of monomers per oligomer, struggle to yield reliable results for large protein aggregates, such as amyloid oligomers. We have previously demonstrated the use of a combination of single-molecule photobleaching and substoichiometric fluorescent labeling to determine the aggregation number of oligomers of human α-synuclein, implicated in Parkinson's disease. We show here that this approach is capable of accurately resolving mixtures of multiple distinct molecular species present in the same sample of dopamine-induced α-synuclein oligomers, and that we can determine the respective aggregation numbers of each species from a single histogram of bleaching steps. We found two distinct species with aggregation numbers of 15-19 monomers and 34-38 monomers. These results show that this single-molecule approach allows for the systematic study of the aggregation numbers of complex supramolecular assemblies formed under different aggregation conditions.
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Affiliation(s)
- Niels Zijlstra
- Nanobiophysics, MESA+ Institute for Nanotechnology, University of Twente, Enschede, The Netherlands
| | - Mireille M A E Claessens
- Nanobiophysics, MESA+ Institute for Nanotechnology, University of Twente, Enschede, The Netherlands
| | - Christian Blum
- Nanobiophysics, MESA+ Institute for Nanotechnology, University of Twente, Enschede, The Netherlands
| | - Vinod Subramaniam
- Nanobiophysics, MESA+ Institute for Nanotechnology, University of Twente, Enschede, The Netherlands; Nanobiophysics, MIRA Institute for Biomedical Technology and Technical Medicine, University of Twente, Enschede, The Netherlands.
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Carmo-Gonçalves P, Pinheiro AS, Romão L, Cortines J, Follmer C. UV-induced selective oxidation of Met5 to Met-sulfoxide leads to the formation of neurotoxic fibril-incompetent α-synuclein oligomers. Amyloid 2014; 21:163-74. [PMID: 24784227 DOI: 10.3109/13506129.2014.912208] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Oxidative stress and the formation of cytotoxic aggregates of the presynaptic protein α-synuclein (AS) are two important events associated with the pathogenesis of Parkinson's disease (PD) and several other neurodegenerative diseases. In this context, extensive efforts have been made to elucidate the molecular basis of the cytotoxic synergy between oxidative stress and AS aggregation. In this study, we demonstrate that the exposure of AS to oxidative stress induced by UV radiation (ASUV) blocks the protein fibrillation, leading to the formation of highly toxic fibril-incompetent oligomers. In addition, ASUV exhibited stronger anti-fibrillogenic properties than H2O2-treated AS, inhibiting the fibrillation of unmodified AS at notably low concentrations. Mass spectrometry indicated that Met5 oxidation to Met-sulfoxide was the only modification promoted by UV exposure, which is reinforced by NMR data indicating that Met5 is the only residue whose amide resonance completely disappeared from the (1)H-(15)N HSQC spectrum after UV exposure. This result is supported by previous data that indicate that C-terminal Met residues (Met116 and Met127) and N-terminal Met1 are less susceptible to oxidation than Met5 because of the residual structure of the disordered AS monomer. Overall, our findings suggest that specific oxidation of Met5 might be sufficient to promote the formation of highly neurotoxic oligomers of AS.
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Planchard MS, Exley SE, Morgan SE, Rangachari V. Dopamine-induced α-synuclein oligomers show self- and cross-propagation properties. Protein Sci 2014; 23:1369-79. [PMID: 25044276 DOI: 10.1002/pro.2521] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2014] [Accepted: 07/11/2014] [Indexed: 12/22/2022]
Abstract
Amyloid aggregates of α-synuclein (αS) protein are the predominant species present within the intracellular inclusions called Lewy bodies in Parkinson's disease (PD) patients. Among various aggregates, the low-molecular weight ones broadly ranging between 2 and 30 mers are known to be the primary neurotoxic agents responsible for the impairment of neuronal function. Recent research has indicated that the neurotransmitter dopamine (DA) is one of the key physiological agents promoting and augmenting αS aggregation, which is thought to be a significant event in PD pathologenesis. Specifically, DA is known to induce the formation of soluble oligomers of αS, which in turn are responsible for inducing several important cellular changes leading to cellular toxicity. In this report, we present the generation, isolation, and biophysical characterization of five different dopamine-derived αS oligomers (DSOs) ranging between 3 and 15 mers, corroborating previously published reports. More importantly, we establish that these DSOs are also capable of replication by self-propagation, which leads to the replication of DSOs upon interaction with αS monomers, a process similar to that observed in mammilian prions. In addition, DSOs are also able to cross-propagate amyloid-β (Aβ) aggregates involved in Alzheimer's disease (AD). Interestingly, while self-propagation of DSOs occur with no net gain in protein structure, cross-propagation proceeds with an overall gain in β-sheet conformation. These results implicate the involvement of DSOs in the progression of PD, and, in part, provide a molecular basis for the observed co-existence of AD-like pathology among PD patients.
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Affiliation(s)
- Matthew S Planchard
- Department of Chemistry and Biochemistry, University of Southern Mississippi, Hattiesburg, Mississippi, 39406
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55
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Zhang H, Duan C, Yang H. Defective autophagy in Parkinson's disease: lessons from genetics. Mol Neurobiol 2014; 51:89-104. [PMID: 24990317 DOI: 10.1007/s12035-014-8787-5] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2014] [Accepted: 06/09/2014] [Indexed: 01/09/2023]
Abstract
Parkinson's disease (PD) is the most prevalent neurodegenerative movement disorder. Genetic studies over the past two decades have greatly advanced our understanding of the etiological basis of PD and elucidated pathways leading to neuronal degeneration. Recent studies have suggested that abnormal autophagy, a well conserved homeostatic process for protein and organelle turnover, may contribute to neurodegeneration in PD. Moreover, many of the proteins related to both autosomal dominant and autosomal recessive PD, such as α-synuclein, PINK1, Parkin, LRRK2, DJ-1, GBA, and ATPA13A2, are also involved in the regulation of autophagy. We propose that reduced autophagy enhances the accumulation of α-synuclein, other pathogenic proteins, and dysfunctional mitochondria in PD, leading to oxidative stress and neuronal death.
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Affiliation(s)
- H Zhang
- Center of Parkinson's Disease Beijing Institute for Brain Disorders, Key Laboratory for Neurodegenerative Disease of the Ministry of Education, Department of Neurobiology Capital Medical University, Beijing, 100069, China
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Follmer C. Monoamine oxidase and α-synuclein as targets in Parkinson’s disease therapy. Expert Rev Neurother 2014; 14:703-16. [DOI: 10.1586/14737175.2014.920235] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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Weids AJ, Grant CM. The yeast peroxiredoxin Tsa1 protects against protein-aggregate-induced oxidative stress. J Cell Sci 2014; 127:1327-35. [PMID: 24424024 PMCID: PMC3953820 DOI: 10.1242/jcs.144022] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Peroxiredoxins are ubiquitous thiol-specific proteins that have multiple functions in stress protection, including protection against oxidative stress. Tsa1 is the major yeast peroxiredoxin and we show that it functions as a specific antioxidant to protect the cell against the oxidative stress caused by nascent-protein misfolding and aggregation. Yeast mutants lacking TSA1 are sensitive to misfolding caused by exposure to the proline analogue azetidine-2-carboxylic acid (AZC). AZC promotes protein aggregation, and its toxicity to a tsa1 mutant is caused by the production of reactive oxygen species (ROS). The generation of [rho0] cells, which lack mitochondrial DNA, rescues the tsa1 mutant AZC sensitivity, indicating that mitochondria are the source of ROS. Inhibition of nascent-protein synthesis with cycloheximide prevents AZC-induced protein aggregation and abrogates ROS generation, confirming that the formation of aggregates causes ROS production. Protein aggregation is accompanied by mitochondrial fragmentation, and we show that Tsa1 localises to the sites of protein aggregation. Protein aggregates are formed adjacent to mitochondria, and our data indicate that active mitochondria generate ROS. These data indicate a new role for peroxiredoxins in protecting against ROS that are generated as a result of protein misfolding and aggregate formation.
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Affiliation(s)
- Alan J Weids
- The University of Manchester, Faculty of Life Sciences, Manchester M13 9PT, UK
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58
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Ha Y, Yang A, Lee S, Kim K, Liew H, Lee SH, Lee JE, Lee HI, Suh YH, Park HS, Churchill DG. Dopamine and Cu+/2+can induce oligomerization of α-synuclein in the absence of oxygen: Two types of oligomerization mechanisms for α-synuclein and related cell toxicity studies. J Neurosci Res 2013; 92:359-68. [DOI: 10.1002/jnr.23323] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2013] [Revised: 09/30/2013] [Accepted: 10/14/2013] [Indexed: 02/05/2023]
Affiliation(s)
- Yonghwang Ha
- Department of Chemistry; Korea Advanced Institute of Science and Technology (KAIST); Daejeon Republic of Korea
- Convergence Science and Technology Research Center (CSTRC); Jungwon University; Chungbuk Republic of Korea
| | - Aerin Yang
- Department of Chemistry; Korea Advanced Institute of Science and Technology (KAIST); Daejeon Republic of Korea
| | - Seyoung Lee
- Department of Chemistry; Korea Advanced Institute of Science and Technology (KAIST); Daejeon Republic of Korea
| | - Kibong Kim
- Department of Chemistry; Korea Advanced Institute of Science and Technology (KAIST); Daejeon Republic of Korea
| | - Hyunjeong Liew
- Convergent Research Consortium for Immunologic Disease I Cardiovascular Research Laboratory; Annex to Seoul St. Mary's Hospital; Seoul Korea
| | - Sang Hyung Lee
- Department of Neurosurgery, SMG-SNU Boramae Medical Center; College of Medicine, Seoul National University; Seoul Korea
| | - Ju Eun Lee
- Department of Chemistry and Green-Nano Materials Research Center; Kyungpook National University; Daegu Republic of Korea
| | - Hong-In Lee
- Department of Chemistry and Green-Nano Materials Research Center; Kyungpook National University; Daegu Republic of Korea
| | - Yoo-Hun Suh
- Department of Pharmacology, College of Medicine; Seoul National University; Seoul Korea
- Korea Brain Research Institute; Daegu Republic of Korea
| | - Hee-Sung Park
- Department of Chemistry; Korea Advanced Institute of Science and Technology (KAIST); Daejeon Republic of Korea
| | - David G. Churchill
- Department of Chemistry; Korea Advanced Institute of Science and Technology (KAIST); Daejeon Republic of Korea
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The interplay between lipids and dopamine on α-synuclein oligomerization and membrane binding. Biosci Rep 2013; 33:BSR20130092. [PMID: 24066973 PMCID: PMC3804888 DOI: 10.1042/bsr20130092] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
The deposition of α-syn (α-synuclein) as amyloid fibrils and the selective loss of DA (dopamine) containing neurons in the substantia nigra are two key features of PD (Parkinson's disease). α-syn is a natively unfolded protein and adopts an α-helical conformation upon binding to lipid membrane. Oligomeric species of α-syn have been proposed to be the pathogenic species associated with PD because they can bind lipid membranes and disrupt membrane integrity. DA is readily oxidized to generate reactive intermediates and ROS (reactive oxygen species) and in the presence of DA, α-syn form of SDS-resistant soluble oligomers. It is postulated that the formation of the α-syn:DA oligomers involves the cross-linking of DA-melanin with α-syn, via covalent linkage, hydrogen and hydrophobic interactions. We investigate the effect of lipids on DA-induced α-syn oligomerization and studied the ability of α-syn:DA oligomers to interact with lipids vesicles. Our results show that the interaction of α-syn with lipids inhibits the formation of DA-induced α-syn oligomers. Moreover, the α-syn:DA oligomer cannot interact with lipid vesicles or cause membrane permeability. Thus, the formation of α-syn:DA oligomers may alter the actions of α-syn which require membrane association, leading to disruption of its normal cellular function.
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60
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Illes-Toth E, Dalton CF, Smith DP. Binding of Dopamine to Alpha-Synuclein is Mediated by Specific Conformational States. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2013; 24:1346-54. [PMID: 23817832 PMCID: PMC3738842 DOI: 10.1007/s13361-013-0676-z] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2013] [Revised: 05/08/2013] [Accepted: 05/09/2013] [Indexed: 05/11/2023]
Abstract
Parkinson's disease is the second most common neurodegenerative disorder, in which both alpha-synuclein (α-syn) and dopamine (DA) have a critical role. α-Syn is known to be natively unstructured in equilibrium with subpopulations of more compact structures. It is these compact structures that are thought to be linked to amyloid formation. In the presence of DA, α-syn yields a diverse range of SDS-resistant, non-amyloid oligomers, however the precursor state conformation has not been established. Here, three DA molecules have been observed to bind per α-syn monomer by electrospray-ionization-ion mobility spectrometry-mass spectrometry (ESI-IMS-MS). Each of these DA molecules binds exclusively to the extended conformation of α-syn, and binding is not observed in the compact state of the protein. Measurements of collisional cross sectional areas show that the incremental uptake of DA pushes the protein towards a highly extended population, becoming fully populated upon the binding of three DA ligands. Tyrosine (Tyr) as a closely related structural analog, exhibited limited binding to the protein as compared with DA, with a maximum of two ligands being observed. Those Tyr ligands that do bind were observed as adducts to the extended conformation akin to DA. These findings suggest DA is able to modulate α-syn self-assembly by inducing the population of a highly extended state.
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Affiliation(s)
- Eva Illes-Toth
- Biomedical Research Centre, Sheffield Hallam University, Sheffield, S1 1WB United Kingdom
| | - Caroline F. Dalton
- Biomedical Research Centre, Sheffield Hallam University, Sheffield, S1 1WB United Kingdom
| | - David P. Smith
- Biomedical Research Centre, Sheffield Hallam University, Sheffield, S1 1WB United Kingdom
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Pham CLL, Kirby N, Wood K, Ryan T, Roberts B, Sokolova A, Barnham KJ, Masters CL, Knott RB, Cappai R, Curtain CC, Rekas A. Guanidine hydrochloride denaturation of dopamine-induced α-synuclein oligomers: A small-angle X-ray scattering study. Proteins 2013; 82:10-21. [DOI: 10.1002/prot.24332] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2012] [Revised: 05/10/2013] [Accepted: 05/19/2013] [Indexed: 01/18/2023]
Affiliation(s)
- Chi L. L. Pham
- Department of Pathology and Bio21 Molecular Science and Technology Institute; The University of Melbourne; Victoria 3010 Australia
| | - Nigel Kirby
- SAXS/WAXS Beamline, The Australian Synchrotron; Clayton Victoria 3168 Australia
| | - Kathleen Wood
- Australian Nuclear Science and Technology Organisation (ANSTO); Kirrawee New South Wales 2232 Australia
| | - Timothy Ryan
- The University of Melbourne, Florey Institute of Neuroscience and Mental Health; Victoria 3010 Australia
| | - Blaine Roberts
- The University of Melbourne, Florey Institute of Neuroscience and Mental Health; Victoria 3010 Australia
| | - Anna Sokolova
- Australian Nuclear Science and Technology Organisation (ANSTO); Kirrawee New South Wales 2232 Australia
| | - Kevin J. Barnham
- The University of Melbourne, Florey Institute of Neuroscience and Mental Health; Victoria 3010 Australia
| | - Colin L. Masters
- The University of Melbourne, Florey Institute of Neuroscience and Mental Health; Victoria 3010 Australia
| | - Robert B. Knott
- Australian Nuclear Science and Technology Organisation (ANSTO); Kirrawee New South Wales 2232 Australia
| | - Roberto Cappai
- Department of Pathology and Bio21 Molecular Science and Technology Institute; The University of Melbourne; Victoria 3010 Australia
| | - Cyril C. Curtain
- Department of Pathology and Bio21 Molecular Science and Technology Institute; The University of Melbourne; Victoria 3010 Australia
- The University of Melbourne, Florey Institute of Neuroscience and Mental Health; Victoria 3010 Australia
| | - Agata Rekas
- Australian Nuclear Science and Technology Organisation (ANSTO); Kirrawee New South Wales 2232 Australia
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Abstract
α-Synuclein is a presynaptic neuronal protein that is linked genetically and neuropathologically to Parkinson's disease (PD). α-Synuclein may contribute to PD pathogenesis in a number of ways, but it is generally thought that its aberrant soluble oligomeric conformations, termed protofibrils, are the toxic species that mediate disruption of cellular homeostasis and neuronal death, through effects on various intracellular targets, including synaptic function. Furthermore, secreted α-synuclein may exert deleterious effects on neighboring cells, including seeding of aggregation, thus possibly contributing to disease propagation. Although the extent to which α-synuclein is involved in all cases of PD is not clear, targeting the toxic functions conferred by this protein when it is dysregulated may lead to novel therapeutic strategies not only in PD, but also in other neurodegenerative conditions, termed synucleinopathies.
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Affiliation(s)
- Leonidas Stefanis
- Laboratory of Neurodegenerative Diseases, Biomedical Research Foundation of the Academy of Athens, and Second Department of Neurology, University of Athens Medical School, Athens 11527, Greece.
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63
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Schildknecht S, Gerding HR, Karreman C, Drescher M, Lashuel HA, Outeiro TF, Di Monte DA, Leist M. Oxidative and nitrative alpha-synuclein modifications and proteostatic stress: implications for disease mechanisms and interventions in synucleinopathies. J Neurochem 2013; 125:491-511. [PMID: 23452040 DOI: 10.1111/jnc.12226] [Citation(s) in RCA: 85] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2012] [Revised: 02/21/2013] [Accepted: 02/21/2013] [Indexed: 12/22/2022]
Abstract
Alpha-synuclein (ASYN) is a major constituent of the typical protein aggregates observed in several neurodegenerative diseases that are collectively referred to as synucleinopathies. A causal involvement of ASYN in the initiation and progression of neurological diseases is suggested by observations indicating that single-point (e.g., A30P, A53T) or multiplication mutations of the gene encoding for ASYN cause early onset forms of Parkinson's disease (PD). The relative regional specificity of ASYN pathology is still a riddle that cannot be simply explained by its expression pattern. Also, transgenic over-expression of ASYN in mice does not recapitulate the typical dopaminergic neuronal death observed in PD. Thus, additional factors must contribute to ASYN-related toxicity. For instance, synucleinopathies are usually associated with inflammation and elevated levels of oxidative stress in affected brain areas. In turn, these conditions favor oxidative modifications of ASYN. Among these modifications, nitration of tyrosine residues, formation of covalent ASYN dimers, as well as methionine sulfoxidations are prominent examples that are observed in post-mortem PD brain sections. Oxidative modifications can affect ASYN aggregation, as well as its binding to biological membranes. This would affect neurotransmitter recycling, mitochondrial function and dynamics (fission/fusion), ASYN's degradation within a cell and, possibly, the transfer of modified ASYN to adjacent cells. Here, we propose a model on how covalent modifications of ASYN link energy stress, altered proteostasis, and oxidative stress, three major pathogenic processes involved in PD progression. Moreover, we hypothesize that ASYN may act physiologically as a catalytically regenerated scavenger of oxidants in healthy cells, thus performing an important protective role prior to the onset of disease or during aging.
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Affiliation(s)
- Stefan Schildknecht
- Department of Biology, Doerenkamp-Zbinden Chair for In vitro Toxicology and Biomedicine, University of Konstanz, Konstanz, Germany.
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Nakaso K, Tajima N, Ito S, Teraoka M, Yamashita A, Horikoshi Y, Kikuchi D, Mochida S, Nakashima K, Matsura T. Dopamine-mediated oxidation of methionine 127 in α-synuclein causes cytotoxicity and oligomerization of α-synuclein. PLoS One 2013; 8:e55068. [PMID: 23457458 PMCID: PMC3573015 DOI: 10.1371/journal.pone.0055068] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2012] [Accepted: 12/17/2012] [Indexed: 11/24/2022] Open
Abstract
Parkinson's disease (PD) is a neurodegenerative disorder characterized by the selective loss of dopaminergic neurons and the presence of Lewy bodies. Many recent studies focused on the interaction between α-synuclein (α-syn) and dopamine in the pathogenesis of PD, and fluorescent anisotropy suggested that the C-terminal region of α-syn may be a target for modification by dopamine. However, it is not well understood why PD-related pathogenesis occurs selectively in dopaminergic neurons. We investigated the interaction between dopamine and α-syn with regard to cytotoxicity. A soluble oligomer was formed by co-incubating α-syn and dopamine in vitro. To clarify the effect of dopamine on α-syn in cells, we generated PC12 cells expressing human α-syn, as well as the α-syn mutants, M116A, Y125D, M127A, S129A, and M116A/M127A, in a tetracycline-inducible manner (PC12-TetOFF-α-syn). Overexpression of wildtype α-syn in catecholaminergic PC12 cells decreased cell viability in long-term cultures, while a competitive inhibitor of tyrosine hydroxylase blocked this vulnerability, suggesting that α-syn-related cytotoxicity is associated with dopamine metabolism. The vulnerabilities of all mutant cell lines were lower than that of wildtype α-syn-expressing cells. Moreover, α-syn containing dopamine-mediated oxidized methionine (Met(O)) was detected in PC12-TetOFF-α-syn. Met(O) was lower in methionine mutant cells, especially in the M127A or M116A/M127A mutants, but also in the Y125D and S129A mutants. Co-incubation of dopamine and the 125YEMPS129 peptide enhanced the production of H2O2, which may oxidize methionine residues and convert them to Met(O). Y125- or S129-lacking peptides did not enhance the dopamine-related production of H2O2. Our results suggest that M127 is the major target for oxidative modification by dopamine, and that Y125 and S129 may act as enhancers of this modification. These results may describe a mechanism of dopaminergic neuron-specific toxicity of α-syn in the pathogenesis of PD.
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Affiliation(s)
- Kazuhiro Nakaso
- Division of Medical Biochemistry, Department of Pathophysiological and Therapeutic Science, Tottori University Faculty of Medicine, Yonago, Japan.
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da Silva FL, Coelho Cerqueira E, de Freitas MS, Gonçalves DL, Costa LT, Follmer C. Vitamins K interact with N-terminus α-synuclein and modulate the protein fibrillization in vitro. Exploring the interaction between quinones and α-synuclein. Neurochem Int 2012; 62:103-12. [PMID: 23064431 DOI: 10.1016/j.neuint.2012.10.001] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2012] [Revised: 10/01/2012] [Accepted: 10/03/2012] [Indexed: 01/29/2023]
Abstract
In the last decades, a series of compounds, including quinones and polyphenols, has been described as having anti-fibrillogenic action on α-synuclein (α-syn) whose aggregation is associated to the pathogenesis of Parkinson's disease (PD). Most of these molecules act as promiscuous anti-amyloidogenic agents, interacting with the diverse amyloidogenic proteins (mostly unfolded) through non-specific hydrophobic interactions. Herein we investigated the effect of the vitamins K (phylloquinone, menaquinone and menadione), which are 1,4-naphthoquinone (1,4-NQ) derivatives, on α-syn aggregation, comparing them with other anti-fibrillogenic molecules such as quinones, polyphenols and lipophilic vitamins. Vitamins K delayed α-syn fibrillization in substoichiometric concentrations, leading to the formation of short, sheared fibrils and amorphous aggregates, which are less prone to produce leakage of synthetic vesicles. In seeding conditions, menadione and 1,4-NQ significantly inhibited fibrils elongation, which could be explained by their ability to destabilize preformed fibrils of α-syn. Bidimensional NMR experiments indicate that a specific site at the N-terminal α-syn (Gly31/Lys32) is involved in the interaction with vitamins K, which is corroborated by previous studies suggesting that Lys is a key residue in the interaction with quinones. Together, our data suggest that 1,4-NQ, recently showed up by our group as a potential scaffold for designing new monoamine oxidase inhibitors, is also capable to modulate α-syn fibrillization in vitro.
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Affiliation(s)
- Fernanda Luna da Silva
- Department of Physical Chemistry, Institute of Chemistry, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-909, Brazil
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66
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Beyer K, Ariza A. Alpha-Synuclein Posttranslational Modification and Alternative Splicing as a Trigger for Neurodegeneration. Mol Neurobiol 2012; 47:509-24. [DOI: 10.1007/s12035-012-8330-5] [Citation(s) in RCA: 97] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2012] [Accepted: 08/13/2012] [Indexed: 12/11/2022]
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67
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Cui ZJ, Han ZQ, Li ZY. Modulating protein activity and cellular function by methionine residue oxidation. Amino Acids 2012; 43:505-17. [PMID: 22146868 DOI: 10.1007/s00726-011-1175-9] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2011] [Accepted: 11/21/2011] [Indexed: 02/07/2023]
Abstract
The sulfur-containing amino acid residue methionine (Met) in a peptide/protein is readily oxidized to methionine sulfoxide [Met(O)] by reactive oxygen species both in vitro and in vivo. Methionine residue oxidation by oxidants is found in an accumulating number of important proteins. Met sulfoxidation activates calcium/calmodulin-dependent protein kinase II and the large conductance calcium-activated potassium channels, delays inactivation of the Shaker potassium channel ShC/B and L-type voltage-dependent calcium channels. Sulfoxidation at critical Met residues inhibits fibrillation of atherosclerosis-related apolipoproteins and multiple neurodegenerative disease-related proteins, such as amyloid beta, α-synuclein, prion, and others. Methionine residue oxidation is also correlated with marked changes in cellular activities. Controlled key methionine residue oxidation may be used as an oxi-genetics tool to dissect specific protein function in situ.
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Affiliation(s)
- Zong Jie Cui
- Institute of Cell Biology, Beijing Normal University, Beijing 100875, China.
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68
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Chan T, Chow AM, Cheng XR, Tang DWF, Brown IR, Kerman K. Oxidative stress effect of dopamine on α-synuclein: electroanalysis of solvent interactions. ACS Chem Neurosci 2012; 3:569-74. [PMID: 22860226 DOI: 10.1021/cn300034t] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2012] [Accepted: 05/16/2012] [Indexed: 11/30/2022] Open
Abstract
The interaction of dopamine (DA) and α-synuclein (α-S) can lead to protein misfolding and neuronal death triggered by oxidative stress relevant to the progression of Parkinson's disease (PD). In this study, interfacial properties associated with DA-induced α-S aggregation under various solution conditions (i.e., pH, ionic strength) were investigated in vitro. The electrochemical oxidation of tyrosine (Tyr) residues in α-S was detected in the presence of DA. DA concentration dependence was analyzed and found to significantly affect α-S aggregation pathways. At low pH, DA was shown to be stable and produced no observable difference in interfacial properties. Between pH 7 and 11, DA promoted α-S aggregation. Significant differences in oxidation current signals in response to high pH and ionic strength suggested the importance of initial interactions in the stabilization of toxic oligomeric structures and subsequent off-pathways of α-S. Our results demonstrate the importance of solution interactions with α-S and the unique information that electrochemical techniques can provide for the investigation of α-S aggregation at early stages, an important step toward the development of future PD therapeutics.
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Affiliation(s)
- Tiffiny Chan
- Department
of Physical and Environmental Sciences, ‡Centre for the Neurobiology of
Stress, Department of Biological Sciences, University of Toronto Scarborough, 1265 Military Trail,
Toronto, ON, M1C 1A4 Canada
| | - Ari M. Chow
- Department
of Physical and Environmental Sciences, ‡Centre for the Neurobiology of
Stress, Department of Biological Sciences, University of Toronto Scarborough, 1265 Military Trail,
Toronto, ON, M1C 1A4 Canada
| | - Xin R. Cheng
- Department
of Physical and Environmental Sciences, ‡Centre for the Neurobiology of
Stress, Department of Biological Sciences, University of Toronto Scarborough, 1265 Military Trail,
Toronto, ON, M1C 1A4 Canada
| | - Derek W. F. Tang
- Department
of Physical and Environmental Sciences, ‡Centre for the Neurobiology of
Stress, Department of Biological Sciences, University of Toronto Scarborough, 1265 Military Trail,
Toronto, ON, M1C 1A4 Canada
| | - Ian R. Brown
- Department
of Physical and Environmental Sciences, ‡Centre for the Neurobiology of
Stress, Department of Biological Sciences, University of Toronto Scarborough, 1265 Military Trail,
Toronto, ON, M1C 1A4 Canada
| | - Kagan Kerman
- Department
of Physical and Environmental Sciences, ‡Centre for the Neurobiology of
Stress, Department of Biological Sciences, University of Toronto Scarborough, 1265 Military Trail,
Toronto, ON, M1C 1A4 Canada
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69
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Ono K, Li L, Takamura Y, Yoshiike Y, Zhu L, Han F, Mao X, Ikeda T, Takasaki JI, Nishijo H, Takashima A, Teplow DB, Zagorski MG, Yamada M. Phenolic compounds prevent amyloid β-protein oligomerization and synaptic dysfunction by site-specific binding. J Biol Chem 2012; 287:14631-43. [PMID: 22393064 PMCID: PMC3340280 DOI: 10.1074/jbc.m111.325456] [Citation(s) in RCA: 164] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2011] [Revised: 02/28/2012] [Indexed: 11/06/2022] Open
Abstract
Cerebral deposition of amyloid β protein (Aβ) is an invariant feature of Alzheimer disease (AD), and epidemiological evidence suggests that moderate consumption of foods enriched with phenolic compounds reduce the incidence of AD. We reported previously that the phenolic compounds myricetin (Myr) and rosmarinic acid (RA) inhibited Aβ aggregation in vitro and in vivo. To elucidate a mechanistic basis for these results, we analyzed the effects of five phenolic compounds in the Aβ aggregation process and in oligomer-induced synaptic toxicities. We now report that the phenolic compounds blocked Aβ oligomerization, and Myr promoted significant NMR chemical shift changes of monomeric Aβ. Both Myr and RA reduced cellular toxicity and synaptic dysfunction of the Aβ oligomers. These results suggest that Myr and RA may play key roles in blocking the toxicity and early assembly processes associated with Aβ through different binding.
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Affiliation(s)
- Kenjiro Ono
- From the Department of Neurology and Neurobiology and Aging, Kanazawa University Graduate School of Medical Science, Kanazawa 920-8640, Japan
| | - Lei Li
- Department of Chemistry, Case Western Reserve University, Cleveland, Ohio 44106
| | - Yusaku Takamura
- System Emotional Science, University of Toyama, Toyama 930-0194, Japan
| | - Yuji Yoshiike
- the Laboratory for Alzheimer's Disease, Brain Science Institute, Riken, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan, and
| | - Lijun Zhu
- Department of Chemistry, Case Western Reserve University, Cleveland, Ohio 44106
| | - Fang Han
- Department of Chemistry, Case Western Reserve University, Cleveland, Ohio 44106
| | - Xian Mao
- Department of Chemistry, Case Western Reserve University, Cleveland, Ohio 44106
| | - Tokuhei Ikeda
- From the Department of Neurology and Neurobiology and Aging, Kanazawa University Graduate School of Medical Science, Kanazawa 920-8640, Japan
| | - Jun-ichi Takasaki
- From the Department of Neurology and Neurobiology and Aging, Kanazawa University Graduate School of Medical Science, Kanazawa 920-8640, Japan
| | - Hisao Nishijo
- System Emotional Science, University of Toyama, Toyama 930-0194, Japan
| | - Akihiko Takashima
- the Laboratory for Alzheimer's Disease, Brain Science Institute, Riken, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan, and
| | - David B. Teplow
- Department of Neurology and Mary S. Easton Center for Alzheimer's Disease Research at UCLA, David Geffen School of Medicine, and Molecular Biology Institute and Brain Research Institute, UCLA, Los Angeles, California 90095
| | - Michael G. Zagorski
- Department of Chemistry, Case Western Reserve University, Cleveland, Ohio 44106
| | - Masahito Yamada
- From the Department of Neurology and Neurobiology and Aging, Kanazawa University Graduate School of Medical Science, Kanazawa 920-8640, Japan
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70
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Hung LW, Villemagne VL, Cheng L, Sherratt NA, Ayton S, White AR, Crouch PJ, Lim S, Leong SL, Wilkins S, George J, Roberts BR, Pham CLL, Liu X, Chiu FCK, Shackleford DM, Powell AK, Masters CL, Bush AI, O'Keefe G, Culvenor JG, Cappai R, Cherny RA, Donnelly PS, Hill AF, Finkelstein DI, Barnham KJ. The hypoxia imaging agent CuII(atsm) is neuroprotective and improves motor and cognitive functions in multiple animal models of Parkinson's disease. ACTA ACUST UNITED AC 2012; 209:837-54. [PMID: 22473957 PMCID: PMC3328361 DOI: 10.1084/jem.20112285] [Citation(s) in RCA: 131] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The PET imaging agent CuII(atsm) improves motor and cognitive function in Parkinson’s disease. Parkinson’s disease (PD) is a progressive, chronic disease characterized by dyskinesia, rigidity, instability, and tremors. The disease is defined by the presence of Lewy bodies, which primarily consist of aggregated α-synuclein protein, and is accompanied by the loss of monoaminergic neurons. Current therapeutic strategies only give symptomatic relief of motor impairment and do not address the underlying neurodegeneration. Hence, we have identified CuII(atsm) as a potential therapeutic for PD. Drug administration to four different animal models of PD resulted in improved motor and cognition function, rescued nigral cell loss, and improved dopamine metabolism. In vitro, this compound is able to inhibit the effects of peroxynitrite-driven toxicity, including the formation of nitrated α-synuclein oligomers. Our results show that CuII(atsm) is effective in reversing parkinsonian defects in animal models and has the potential to be a successful treatment of PD.
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Affiliation(s)
- Lin W Hung
- The Mental Health Research Institute, the University of Melbourne, Victoria 3010 Australia
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71
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Abstract
Aggregated a-synuclein is the major component of inclusions in Parkinson's disease and other synucleinopathy brains indicating that a-syn aggregation is associated with the pathogenesis of neurodegenerative disorders. Although the mechanisms underlying a-syn aggregation and toxicity are not fully elucidated, it is clear that a-syn undergoes post-translational modifications and interacts with numerous proteins and other macromolecules, metals, hormones, neurotransmitters, drugs and poisons that can all modulate its aggregation propensity. The current and most recent findings regarding the factors modulating a-syn aggregation process are discussed in detail.
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72
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Rochet JC, Hay BA, Guo M. Molecular insights into Parkinson's disease. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2012; 107:125-88. [PMID: 22482450 DOI: 10.1016/b978-0-12-385883-2.00011-4] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Mutations in SNCA, PINK1, parkin, and DJ-1 are associated with autosomal-dominant or autosomal-recessive forms of Parkinson's disease (PD), the second most common neurodegenerative disorder. Studies on the structural and functional properties of the corresponding gene products have provided significant insights into the molecular underpinnings of familial PD and the much more common sporadic forms of the disease. Here, we review recent advances in our understanding of four PD-related gene products: α-synuclein, parkin, PINK1, and DJ-1. In Part 1, we review new insights into the role of α-synuclein in PD. In Part 2, we summarize the latest developments in understanding the role of mitochondrial dysfunction in PD, emphasizing the role of the PINK1/parkin pathway in regulating mitochondrial dynamics and mitophagy. The role of DJ-1 is also discussed. In Part 3, we point out converging pathways and future directions.
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Affiliation(s)
- Jean-Christophe Rochet
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, Indiana, USA
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73
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Lee HJ, Baek SM, Ho DH, Suk JE, Cho ED, Lee SJ. Dopamine promotes formation and secretion of non-fibrillar alpha-synuclein oligomers. Exp Mol Med 2011; 43:216-22. [PMID: 21415592 DOI: 10.3858/emm.2011.43.4.026] [Citation(s) in RCA: 108] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
Parkinson's disease (PD) is characterized by selective and progressive degeneration of dopamine (DA)-producing neurons in the substantia nigra pars compacta (SNpc) and by abnormal aggregation of α-synuclein. Previous studies have suggested that DA can interact with α-synuclein, thus modulating the aggregation process of this protein; this interaction may account for the selective vulnerability of DA neurons in patients with PD. However, the relationship between DA and α-synuclein, and the role in progressive degeneration of DA neurons remains elusive. We have shown that in the presence of DA, recombinant human α-synuclein produces non-fibrillar, SDS-resistant oligomers, while β-sheet-rich fibril formation is inhibited. Pharmacologic elevation of the cytoplasmic DA level increased the formation of SDS-resistant oligomers in DA-producing neuronal cells. DA promoted α-synuclein oligomerization in intracellular vesicles, but not in the cytosol. Furthermore, elevation of DA levels increased secretion of α-synuclein oligomers to the extracellular space, but the secretion of monomers was not changed. DA-induced secretion of α-synuclein oligomers may contribute to the progressive loss of the dopaminergic neuronal population and the pronounced neuroinflammation observed in the SNpc in patients with PD.
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Affiliation(s)
- He-Jin Lee
- Department of Anatomy, School of Medicine, Konkuk University, Seoul, Korea
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74
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Sideri TC, Koloteva-Levine N, Tuite MF, Grant CM. Methionine oxidation of Sup35 protein induces formation of the [PSI+] prion in a yeast peroxiredoxin mutant. J Biol Chem 2011; 286:38924-31. [PMID: 21832086 PMCID: PMC3234717 DOI: 10.1074/jbc.m111.272419] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
The frequency with which the yeast [PSI+] prion form of Sup35 arises de novo is controlled by a number of genetic and environmental factors. We have previously shown that in cells lacking the antioxidant peroxiredoxin proteins Tsa1 and Tsa2, the frequency of de novo formation of [PSI+] is greatly elevated. We show here that Tsa1/Tsa2 also function to suppress the formation of the [PIN+] prion form of Rnq1. However, although oxidative stress increases the de novo formation of both [PIN+] and [PSI+], it does not overcome the requirement of cells being [PIN+] to form the [PSI+] prion. We use an anti-methionine sulfoxide antibody to show that methionine oxidation is elevated in Sup35 during oxidative stress conditions. Abrogating Sup35 methionine oxidation by overexpressing methionine sulfoxide reductase (MSRA) prevents [PSI+] formation, indicating that Sup35 oxidation may underlie the switch from a soluble to an aggregated form of Sup35. In contrast, we were unable to detect methionine oxidation of Rnq1, and MSRA overexpression did not affect [PIN+] formation in a tsa1 tsa2 mutant. The molecular basis of how yeast and mammalian prions form infectious amyloid-like structures de novo is poorly understood. Our data suggest a causal link between Sup35 protein oxidation and de novo [PSI+] prion formation.
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Affiliation(s)
- Theodora C Sideri
- Faculty of Life Sciences, University of Manchester, the Michael Smith Building, Oxford Road, Manchester M13 9PT, United Kingdom
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75
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Meloni G, Vašák M. Redox activity of α-synuclein-Cu is silenced by Zn₇-metallothionein-3. Free Radic Biol Med 2011; 50:1471-9. [PMID: 21320589 DOI: 10.1016/j.freeradbiomed.2011.02.003] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/18/2010] [Revised: 01/25/2011] [Accepted: 02/06/2011] [Indexed: 11/26/2022]
Abstract
The aggregation of α-synuclein (α-Syn), the major component of intracellular Lewy body inclusions in dopaminergic neurons of the substantia nigra, plays a critical role in the etiology of Parkinson disease (PD). Long-term effects of redox-active transition metals (Cu, Fe) and oxidative chemical imbalance underlie the disease progression and neuronal death. In this work, we provide evidence that a brain metalloprotein, Zn₇-metallothionein-3 (Zn₇MT-3), possesses a dynamic role in controlling aberrant protein-copper interactions in PD. We examined the properties of the α-Syn-Cu(II) complex with regard to molecular oxygen, the biological reducing agent ascorbate, and the neurotransmitter dopamine. The results revealed that under aerobic conditions α-Syn-Cu(II) possesses catalytic oxidase activity. The observed metal-centered redox chemistry significantly promotes the production of hydroxyl radicals and α-Syn oxidation and oligomerization, processes considered critical for cellular toxicity. Moreover, we show that Zn₇MT-3, through Cu(II) removal from the α-Syn-Cu(II) complex, efficiently prevents its deleterious redox activity. We demonstrate that the Cu(II) reduction by thiolate ligands of Zn₇MT-3 and the formation of Cu(I)₄Zn₄MT-3, in which an unusual oxygen-stable Cu(I)₄-thiolate cluster is present, comprise the underlying molecular mechanism by which α-Syn and dopamine oxidation, α-Syn oligomerization, and ROS production are abolished. These studies provide new insights into the bioinorganic chemistry of PD.
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Affiliation(s)
- Gabriele Meloni
- Department of Biochemistry, University of Zurich, 8057 Zürich, Switzerland.
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76
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Wang XJ, Zhang S, Yan ZQ, Zhao YX, Zhou HY, Wang Y, Lu GQ, Zhang JD. Impaired CD200-CD200R-mediated microglia silencing enhances midbrain dopaminergic neurodegeneration: roles of aging, superoxide, NADPH oxidase, and p38 MAPK. Free Radic Biol Med 2011; 50:1094-106. [PMID: 21295135 DOI: 10.1016/j.freeradbiomed.2011.01.032] [Citation(s) in RCA: 78] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/30/2010] [Revised: 01/24/2011] [Accepted: 01/25/2011] [Indexed: 11/24/2022]
Abstract
CD200-CD200R signaling holds microglia in a quiescent state. Parkinson disease (PD) neurodegeneration may be associated with impairment of CD200-CD200R-mediated microglia silencing in the substantia nigra (SN). In this study, an anti-CD200R blocking antibody (ACDR) selectively and significantly enhanced the susceptibility of dopaminergic neurons to neurotoxicity induced by rotenone (Rot) and iron (Ir) in mesencephalic neuron/glia cultures. Microglia were shown to mediate dopaminergic neurotoxicity induced by ACDR/Rot (combination of ACDR and Rot) and ACDR/Ir (combination of ACDR and Ir). ACDR significantly enhanced the microglial activation induced by Rot and Ir in neuron/glia cultures. NADPH oxidase-mediated superoxide generation was a key contributor to dopaminergic neurotoxicity induced by ACDR/Rot and ACDR/Ir. p38 MAPK contributed to NADPH oxidase activation induced by ACDR/Rot and ACDR/Ir. Interestingly, there were a decrease in CD200 expression (mRNA and protein) and an enhancement of microglial response (MHCII mRNA and ICAM-1 protein) in the rat SN with aging. ICAM-1 expression was significantly inversely correlated with CD200 expression. These results strongly indicate the participation of SN CD200-CD200R dysfunction in the etiopathogenesis of PD and provide a new insight into the molecular mechanisms underlying the involvement of aging in PD and help to elucidate the mechanisms of the combined involvement of immune/inflammatory factors, environmental substances, and aging in PD.
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Affiliation(s)
- Xi-Jin Wang
- Department of Neurology and Institute of Neurology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China.
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77
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Esteves AR, Arduíno DM, Silva DFF, Oliveira CR, Cardoso SM. Mitochondrial Dysfunction: The Road to Alpha-Synuclein Oligomerization in PD. PARKINSON'S DISEASE 2011; 2011:693761. [PMID: 21318163 PMCID: PMC3026982 DOI: 10.4061/2011/693761] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/20/2010] [Revised: 12/21/2010] [Accepted: 12/27/2010] [Indexed: 12/21/2022]
Abstract
While the etiology of Parkinson's disease remains largely elusive, there is accumulating evidence suggesting that mitochondrial dysfunction occurs prior to the onset of symptoms in Parkinson's disease. Mitochondria are remarkably primed to play a vital role in neuronal cell survival since they are key regulators of energy metabolism (as ATP producers), of intracellular calcium homeostasis, of NAD(+)/NADH ratio, and of endogenous reactive oxygen species production and programmed cell death. In this paper, we focus on mitochondrial dysfunction-mediated alpha-synuclein aggregation. We highlight some of the findings that provide proof of evidence for a mitochondrial metabolism control in Parkinson's disease, namely, mitochondrial regulation of microtubule-dependent cellular traffic and autophagic lysosomal pathway. The knowledge that microtubule alterations may lead to autophagic deficiency and may compromise the cellular degradation mechanisms that culminate in the progressive accumulation of aberrant protein aggregates shields new insights to the way we address Parkinson's disease. In line with this knowledge, an innovative window for new therapeutic strategies aimed to restore microtubule network may be unlocked.
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Affiliation(s)
- A. R. Esteves
- Centro de Neurociências e Biologia Celular, Universidade de Coimbra, 3004 Coimbra, Portugal
| | - D. M. Arduíno
- Centro de Neurociências e Biologia Celular, Universidade de Coimbra, 3004 Coimbra, Portugal
| | - D. F. F. Silva
- Centro de Neurociências e Biologia Celular, Universidade de Coimbra, 3004 Coimbra, Portugal
| | - C. R. Oliveira
- Centro de Neurociências e Biologia Celular, Universidade de Coimbra, 3004 Coimbra, Portugal
- Faculdade de Medicina, Universidade de Coimbra, 3000 Coimbra, Portugal
| | - S. M. Cardoso
- Centro de Neurociências e Biologia Celular, Universidade de Coimbra, 3004 Coimbra, Portugal
- Faculdade de Medicina, Universidade de Coimbra, 3000 Coimbra, Portugal
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78
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Oien DB, Carrasco GA, Moskovitz J. Decreased Phosphorylation and Increased Methionine Oxidation of α-Synuclein in the Methionine Sulfoxide Reductase A Knockout Mouse. JOURNAL OF AMINO ACIDS 2011; 2011:721094. [PMID: 22332004 PMCID: PMC3275937 DOI: 10.4061/2011/721094] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/31/2010] [Accepted: 12/11/2010] [Indexed: 11/20/2022]
Abstract
Previously, we have showed that overexpression of methionine-oxidized α-synuclein in methionine sulfoxide reductase A (MsrA) null mutant yeast cells inhibits α-synuclein phosphorylation and increases protein fibrillation. The current studies show that ablation of mouse MsrA gene caused enhanced methionine oxidation of α-synuclein while reducing its own phophorylation levels, especially in the hydrophobic cell-extracted fraction. These data provide supportive evidence that a compromised MsrA function in mammalian brain may cause enhanced pathologies associated with altered α-synuclein oxidation and phosphorylation levels.
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Affiliation(s)
- Derek B Oien
- Department of Pharmacology and Toxicology, School of Pharmacy, The University of Kansas, Lawrence, KS 66045, USA
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79
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Oien DB, Carrasco GA, Moskovitz J. Decreased Phosphorylation and Increased Methionine Oxidation of α-Synuclein in the Methionine Sulfoxide Reductase A Knockout Mouse. JOURNAL OF AMINO ACIDS 2011. [PMID: 22332004 DOI: 10.4061/2011/721094 [epub ahead of print]] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Previously, we have showed that overexpression of methionine-oxidized α-synuclein in methionine sulfoxide reductase A (MsrA) null mutant yeast cells inhibits α-synuclein phosphorylation and increases protein fibrillation. The current studies show that ablation of mouse MsrA gene caused enhanced methionine oxidation of α-synuclein while reducing its own phophorylation levels, especially in the hydrophobic cell-extracted fraction. These data provide supportive evidence that a compromised MsrA function in mammalian brain may cause enhanced pathologies associated with altered α-synuclein oxidation and phosphorylation levels.
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Affiliation(s)
- Derek B Oien
- Department of Pharmacology and Toxicology, School of Pharmacy, The University of Kansas, Lawrence, KS 66045, USA
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80
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Davies P, Wang X, Sarell CJ, Drewett A, Marken F, Viles JH, Brown DR. The synucleins are a family of redox-active copper binding proteins. Biochemistry 2010; 50:37-47. [PMID: 21117662 DOI: 10.1021/bi101582p] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Thermodynamic studies in conjunction with EPR confirm that α-synuclein, β-synuclein, and γ-synuclein bind copper(II) in a high affinity 1:1 stoichiometry. γ-Synuclein demonstrates the highest affinity, in the picomolar range, while α-synuclein and β-synuclein both bind copper(II) with nanomolar affinity. The copper center on all three proteins demonstrates reversible or partly reversible redox cycling. Various mutations show that the primary coordinating ligand for copper(II) is located within the N-terminal regions between residues 2-9. There is also a contribution from the C-terminus in conjunction with the histidine at position 50 in α-synuclein and position 65 in β-synuclein, although these regions appear to have little effect on overall coordination stability. These histidines and the C-terminus, however, appear to be critical to the redox engine of the proteins.
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Affiliation(s)
- Paul Davies
- Department of Biology and Biochemistry, University of Bath, Claverton Down, Bath BA27AY, UK
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81
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Different Mechanisms Between Copper and Iron in Catecholamines-Mediated Oxidative DNA Damage and Disruption of Gene Expression In Vitro. Neurotox Res 2010; 20:84-92. [DOI: 10.1007/s12640-010-9226-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2010] [Revised: 09/28/2010] [Accepted: 10/18/2010] [Indexed: 10/18/2022]
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82
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Chan T, Chow AM, Tang DW, Li Q, Wang X, Brown IR, Kerman K. Interaction of baicalein and copper with α-synuclein: Electrochemical approach to Parkinson’s Disease. J Electroanal Chem (Lausanne) 2010. [DOI: 10.1016/j.jelechem.2010.07.015] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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83
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Musgrove REJ, King AE, Dickson TC. Neuroprotective Upregulation of Endogenous Alpha-Synuclein Precedes Ubiquitination in Cultured Dopaminergic Neurons. Neurotox Res 2010; 19:592-602. [DOI: 10.1007/s12640-010-9207-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2010] [Revised: 06/16/2010] [Accepted: 06/25/2010] [Indexed: 10/19/2022]
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84
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Rekas A, Knott RB, Sokolova A, Barnham KJ, Perez KA, Masters CL, Drew SC, Cappai R, Curtain CC, Pham CLL. The structure of dopamine induced alpha-synuclein oligomers. EUROPEAN BIOPHYSICS JOURNAL: EBJ 2010; 39:1407-19. [PMID: 20309679 DOI: 10.1007/s00249-010-0595-x] [Citation(s) in RCA: 80] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2009] [Revised: 02/22/2010] [Accepted: 02/28/2010] [Indexed: 12/28/2022]
Abstract
Inclusions of aggregated alpha-synuclein (alpha-syn) in dopaminergic neurons are a characteristic histological marker of Parkinson's disease (PD). In vitro, alpha-syn in the presence of dopamine (DA) at physiological pH forms SDS-resistant non-amyloidogenic oligomers. We used a combination of biophysical techniques, including sedimentation velocity analysis, small angle X-ray scattering (SAXS) and circular dichroism spectroscopy to study the characteristics of alpha-syn oligomers formed in the presence of DA. Our SAXS data show that the trimers formed by the action of DA on alpha-syn consist of overlapping worm-like monomers, with no end-to-end associations. This lack of structure contrasts with the well-established, extensive beta-sheet structure of the amyloid fibril form of the protein and its pre-fibrillar oligomers. We propose on the basis of these and earlier data that oxidation of the four methionine residues at the C- and N-terminal ends of alpha-syn molecules prevents their end-to-end association and stabilises oligomers formed by cross linking with DA-quinone/DA-melanin, which are formed as a result of the redox process, thus inhibiting formation of the beta-sheet structure found in other pre-fibrillar forms of alpha-syn.
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Affiliation(s)
- Agata Rekas
- Australian Nuclear Science and Technology Organisation (ANSTO), Menai, NSW, Australia.
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85
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Bisaglia M, Tosatto L, Munari F, Tessari I, de Laureto PP, Mammi S, Bubacco L. Dopamine quinones interact with alpha-synuclein to form unstructured adducts. Biochem Biophys Res Commun 2010; 394:424-8. [PMID: 20226175 DOI: 10.1016/j.bbrc.2010.03.044] [Citation(s) in RCA: 74] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2010] [Accepted: 03/08/2010] [Indexed: 11/29/2022]
Abstract
alpha-Synuclein (alphasyn) fibril formation is considered a central event in the pathogenesis of Parkinson's disease (PD). In recent years, it has been proposed that prefibrillar annular oligomeric beta-sheet-rich species, called protofibrils, rather than fibrils themselves, may be the neurotoxic species. The oxidation products of dopamine (DAQ) can inhibit alphasyn fibril formation supporting the idea that DAQ might stabilize alphasyn protofibrils. In the present work, through different biochemical and biophysical techniques, we isolated and structurally characterized alphasyn/DAQ adducts. Contrary to protofibrils, we demonstrated that alphasyn/DAQ adducts retain an unfolded conformation. We then investigated the nature of the modifications induced on alphasyn by DAQ. Our results indicate that only a small fraction of alphasyn interacts with DAQ in a covalent way, so that non-covalent interaction appears to be the major modification induced by DAQ on alphasyn.
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Affiliation(s)
- Marco Bisaglia
- Department of Biology, University of Padova, Via U. Bassi 58B, 35121 Padova, Italy
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86
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Jackson JC, Duodu KG, Holse M, Lima de Faria MD, Jordaan D, Chingwaru W, Hansen A, Cencic A, Kandawa-Schultz M, Mpotokwane SM, Chimwamurombe P, de Kock HL, Minnaar A. The morama bean (Tylosema esculentum): a potential crop for southern Africa. ADVANCES IN FOOD AND NUTRITION RESEARCH 2010; 61:187-246. [PMID: 21092905 DOI: 10.1016/b978-0-12-374468-5.00005-2] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The morama bean is an underutilized leguminous oilseed native to the Kalahari Desert and neighboring sandy regions of Botswana, Namibia, and South Africa (Limpopo, North-West, Gauteng, and Northern Cape provinces), and forms part of the diet of the indigenous population in these countries. It is also known as gemsbok bean, moramaboontjie, elandboontjie, braaiboonjie, marama, marumana, tsi, tsin, gami, and ombanui. It is reported as an excellent source of good quality protein (29-39%); its oil (24-48%) is rich in mono- and di-unsaturated fatty acids and contains no cholesterol. Morama is a good source of micronutrients such as calcium, iron, zinc, phosphate, magnesium, and B vitamins including folate. It is also reported to be a potential source of phytonutrients including phenolic compounds (e.g., tannins), trypsin inhibitors, phytates, and oligosaccharides, components which have been shown in other foods to contribute to health in particular, prevention of noncommunicable diseases such as cardiovascular diseases, diabetes, and some cancers. From a nutritional and health perspective, the morama bean has potential commercial value as a cash crop and value-added products, particularly in the communities where it is found.
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Affiliation(s)
- Jose C Jackson
- Centre for Scientific Research, Indigenous Knowledge and Innovation (CESRIKI), University of Botswana, Botswana.
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87
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Martin I, Dawson VL, Dawson TM. The impact of genetic research on our understanding of Parkinson's disease. PROGRESS IN BRAIN RESEARCH 2010; 183:21-41. [PMID: 20696313 DOI: 10.1016/s0079-6123(10)83002-x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Until recently, genetics was thought to play a minor role in the development of Parkinson's disease (PD). Over the last decade, a number of genes that definitively cause PD have been identified, which has led to the generation of disease models based on pathogenic gene variants that recapitulate many features of the disease. These genetic studies have provided novel insight into potential mechanisms underlying the aetiology of PD. This chapter will provide a profile of the genes conclusively linked to PD and will outline the mechanisms of PD pathogenesis implicated by genetic studies. Mitochondrial dysfunction, oxidative stress and impaired ubiquitin-proteasome system function are disease mechanisms that are particularly well supported by genetic studies and are therefore the focus of this chapter.
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Affiliation(s)
- Ian Martin
- NeuroRegeneration and Stem Cell Programs, Institute for Cell Engineering, Johns Hopkins University School of Medicine, Baltimore, MD, USA
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88
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Lucas HR, Lee JC. Effect of dioxygen on copper(II) binding to alpha-synuclein. J Inorg Biochem 2009; 104:245-9. [PMID: 20064662 DOI: 10.1016/j.jinorgbio.2009.12.010] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2009] [Revised: 11/18/2009] [Accepted: 12/14/2009] [Indexed: 11/24/2022]
Abstract
Using the fluorescent amino acid tryptophan (Trp), we have characterized the copper(II) binding of F4W alpha-synuclein in the presence and absence of dioxygen at neutral pH. Variations in Trp fluorescence indicate that copper(II) binding is enhanced by the presence of dioxygen, with the apparent dissociation constant (K(d(app))) changing from 100nM (anaerobic) to 10nM (aerobic). To investigate the possible role of methionine oxidation, complementary work focused on synthetic peptide models of the N-terminal Cu(II)-alpha-syn site, MDV(F/W) and M( *)DV(F/W), where M( *)=methionine sulfoxide. Furthermore, we employed circular dichroism (CD) spectroscopy to demonstrate that the phenyl-to-indole (F-->W) substitution does not alter copper(II) binding properties and to confirm the 1:1 metal-peptide binding stoichiometry. CD comparisons also revealed that Met1 oxidation does not affect the copper-peptide conformation and further suggested the possible existence of a Cu(II)-Trp/Phe (cation-pi) interaction.
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Affiliation(s)
- Heather R Lucas
- Laboratory of Molecular Biophysics, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland 20892-8013, United States
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89
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Metal ion physiopathology in neurodegenerative disorders. Neuromolecular Med 2009; 11:223-38. [PMID: 19946766 DOI: 10.1007/s12017-009-8102-1] [Citation(s) in RCA: 102] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2009] [Accepted: 10/14/2009] [Indexed: 12/14/2022]
Abstract
Metal dyshomeostasis in the brain (BMD) has often been proposed as a possible cause for several neurodegenerative disorders (NDs). Nevertheless, the precise nature of the biochemical mechanisms of metal involvement in NDs is still largely unknown. Mounting evidence suggests that normal aging itself is characterized by, among other features, a significant degree of metal ion dysmetabolism in the brain. This is probably the result of a progressive deterioration of the metal regulatory systems and, at least in some cases, of life-long metal exposure and brain accumulation. Although alterations of metal metabolism do occur to some extent in normal aging, they appear to be highly enhanced under various neuropathological conditions, causing increased oxidative stress and favoring abnormal metal-protein interactions. Intriguingly, despite the fact that most common NDs have a distinct etiological basis, they share striking similarities as they are all characterized by a documented brain metal impairment. This review will primarily focus on the alterations of metal homeostasis that are observed in normal aging and in Alzheimer's disease. We also present a brief survey on BMD in other NDs (Amyotrophic Lateral Sclerosis, Parkinson's, and Prion Protein disease) in order to highlight what represents the most reliable evidence supporting a crucial involvement of metals in neurodegeneration. The opportunities for metal-targeted pharmacological strategies in the major NDs are briefly outlined as well.
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90
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Leong SL, Cappai R, Barnham KJ, Pham CLL. Modulation of alpha-synuclein aggregation by dopamine: a review. Neurochem Res 2009; 34:1838-46. [PMID: 19444607 DOI: 10.1007/s11064-009-9986-8] [Citation(s) in RCA: 90] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2008] [Accepted: 04/23/2009] [Indexed: 12/30/2022]
Abstract
Parkinson's disease (PD) is a progressive neurodegenerative disorder that is characterized by (1) the selective loss of dopaminergic neurons in the substantia nigra and (2) the deposition of misfolded alpha-synuclein (alpha-syn) as amyloid fibrils in the intracellular Lewy bodies in various region of the brain. Current thinking suggests that an interaction between alpha-syn and dopamine (DA) leads to the selective death of neuronal cells and the accumulation of misfolded alpha-syn. However, the exact mechanism by which this occurs is not fully defined. DA oxidation could play a key role is the pathogenesis of PD by causing oxidative stress, mitochondria dysfunction and impairment of protein metabolism. Here, we review the literature on the role of DA and its oxidative intermediates in modulating the aggregation pathways of alpha-syn.
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Affiliation(s)
- Su Ling Leong
- Department of Pathology, Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Parkville, VIC 3010, Australia
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91
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Pham CL, Leong SL, Ali FE, Kenche VB, Hill AF, Gras SL, Barnham KJ, Cappai R. Dopamine and the Dopamine Oxidation Product 5,6-Dihydroxylindole Promote Distinct On-Pathway and Off-Pathway Aggregation of α-Synuclein in a pH-Dependent Manner. J Mol Biol 2009; 387:771-85. [DOI: 10.1016/j.jmb.2009.02.007] [Citation(s) in RCA: 80] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2008] [Revised: 01/06/2009] [Accepted: 02/04/2009] [Indexed: 01/09/2023]
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