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Alpha synuclein processing by MMP-3 - implications for synucleinopathies. Behav Brain Res 2022; 434:114020. [PMID: 35870616 DOI: 10.1016/j.bbr.2022.114020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Revised: 07/01/2022] [Accepted: 07/19/2022] [Indexed: 11/22/2022]
Abstract
α-Synuclein (aSyn) is a protein implicated in physiological functions such as neurotransmitter release at the synapse and the regulation of gene expression in the nucleus. In addition, pathological aSyn assemblies are characteristic for a class of protein aggregation disorders referred to as synucleinopathies, where aSyn aggregates appear as Lewy bodies and Lewy neurites. We recently discovered a novel post-translational pyroglutamate (pGlu) modification at Gln79 of N-truncated aSyn that promotes oligomer formation and neurotoxicity in human synucleinopathies. A priori, the appearance of pGlu79-aSyn in vivo involves a two-step process of free N-terminal Gln79 residue generation and subsequent cyclization of Gln79 into pGlu79. Prime candidate enzymes for these processes are matrix metalloproteinase-3 (MMP-3) and glutaminyl cyclase (QC). Here, we analyzed the expression of aSyn, MMP-3, QC and pGlu79-aSyn in brains of two transgenic mouse models for synucleinopathies (BAC-SNCA and ASO) by triple immunofluorescent labellings and confocal laser scanning microscopy. We report a co-localization of these proteins in brain structures typically affected by aSyn pathology, namely hippocampus in BAC-SNCA mice and substantia nigra in ASO mice. In addition, Western blot analyses revealed a high abundance of QC, MMP-3 and transgenic human aSyn in brain stem and thalamus but lower levels in cortex/hippocampus, whereas endogenous mouse aSyn was found to be most abundant in cortex/hippocampus, followed by thalamus and brain stem. During aging of ASO mice, we observed no differences between controls and transgenic mice in MMP-3 levels but higher QC content in thalamus of 6-month-old transgenic mice. Transgenic human aSyn abundance transiently increased and then showed decrease in oldest ASO mice analyzed. Immunohistochemistry revealed a successive increase in intraneuronal and extracellular formation of pGlu79-aSyn in substantia nigra during aging of ASO mice. Together, our data are supportive for a role of MMP-3 and QC in the generation of pGlu79-aSyn in brains affected by aSyn pathology.
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Petricca L, Chiki N, Hanna-El-Daher L, Aeschbach L, Burai R, Stoops E, Fares MB, Lashuel HA. Comparative Analysis of Total Alpha-Synuclein (αSYN) Immunoassays Reveals That They Do Not Capture the Diversity of Modified αSYN Proteoforms. JOURNAL OF PARKINSON'S DISEASE 2022; 12:1449-1462. [PMID: 35527570 PMCID: PMC9398082 DOI: 10.3233/jpd-223285] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Background: The development of therapeutics for Parkinson’s disease (PD) requires the establishment of biomarker assays to enable stratifying patients, monitoring disease progression, and assessing target engagement. Attempts to develop diagnostic assays based on detecting levels of the α-synuclein (αSYN) protein, a central player in the pathogenesis of PD, have yielded inconsistent results. Objective: To determine whether the three commercial kits that have been extensively used for total αSYN quantification in human biological fluids (from Euroimmun, MSD, and Biolegend) are capable of capturing the diversity and complexity of relevant αSYN proteoforms. Methods: We investigated and compared the ability of the different assays to detect the diversity of αSYN proteoforms using a library of αSYN proteins that comprise the majority of disease-relevant αSYN variants and post-translational modifications (PTMs). Results: Our findings showed that none of the three tested immunoassays accurately capture the totality of relevant αSYN species, and that these assays are unable to recognize most disease-associated C-terminally truncated variants of αSYN. Moreover, several N-terminal truncations and phosphorylation/nitration PTMs differentially modify the level of αSYN detection and recovery by different immunoassays, and a CSF matrix effect was observed for most of the αSYN proteoforms analyzed by the three immunoassays. Conclusion: Our results show that the tested immunoassays do not capture the totality of the relevant αSYN species and therefore may not be appropriate tools to provide an accurate measure of total αSYN levels in samples containing modified forms of the protein. This highlights the need for next generation αSYN immunoassays that capture the diversity of αSYN proteoforms.
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Affiliation(s)
| | - Nour Chiki
- ND Biosciences SA, Epalinges, Switzerland
| | - Layane Hanna-El-Daher
- Laboratory of Molecular and Chemical Biology of Neurodegeneration, Brain Mind Institute,Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Lorène Aeschbach
- Laboratory of Molecular and Chemical Biology of Neurodegeneration, Brain Mind Institute,Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Ritwik Burai
- Laboratory of Molecular and Chemical Biology of Neurodegeneration, Brain Mind Institute,Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Erik Stoops
- ADx NeuroSciences NV, Technologiepark 94 - Bio Incubator, Gent, Belgium
| | | | - Hilal A Lashuel
- ND Biosciences SA, Epalinges, Switzerland.,Laboratory of Molecular and Chemical Biology of Neurodegeneration, Brain Mind Institute,Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
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Lafora Disease and Alpha-Synucleinopathy in Two Adult Free-Ranging Moose (Alces alces) Presenting with Signs of Blindness and Circling. Animals (Basel) 2022; 12:ani12131633. [PMID: 35804532 PMCID: PMC9264765 DOI: 10.3390/ani12131633] [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: 05/30/2022] [Revised: 06/16/2022] [Accepted: 06/20/2022] [Indexed: 11/17/2022] Open
Abstract
Simple Summary Reports of behavioral signs, such as blindness and circling in free-ranging moose from different parts of the world, have spurred comprehensive pathological investigation to find the causes of the disease that have clinical relevance. In this case study, brains collected from two adult free-ranging moose (Alces alces) cows that were seemingly blind and found walking in circles were examined by light and electron microscopy with further ancillary testing. Here, we report for the first time Lafora disease and alpha-synucleinopathy in two wild free-ranging moose cows who presented with abnormal behavior and blindness, with similar neuronal polyglucosan body (PGB) accumulations identified in humans and other animals. Microscopic analysis of the hippocampus of brain revealed inclusion bodies resembling PGBs (Lafora disease) in the neurons with ultrastructural findings of aggregates of branching filaments, consistent with polyglucosan bodies. Furthermore, α-synuclein immunopositivity was noted in the hippocampus, with accumulations of small granules ultrastructurally distinct from PGBs and morphologically compatible with alpha-synucleinopathy (Lewy body). The apparent blindness found in these moose could be related to an injury associated with secondary bacterial invasion; however, an accumulation of neurotoxicants (PGBs and α-synucleins) in retinal ganglion cells could also be the cause. Lafora disease and alpha-synucleinopathy were considered in the differential diagnosis of the young adult moose who presented with signs of blindness and behavioral signs such as circling. Abstract Lafora disease is an autosomal recessive glycogen-storage disorder resulting from an accumulation of toxic polyglucosan bodies (PGBs) in the central nervous system, which causes behavioral and neurologic symptoms in humans and other animals. In this case study, brains collected from two young adult free-ranging moose (Alces alces) cows that were seemingly blind and found walking in circles were examined by light and electron microscopy. Microscopic analysis of the hippocampus of the brain revealed inclusion bodies resembling PGBs in the neuronal perikaryon, neuronal processes, and neuropil. These round inclusions measuring up to 30 microns in diameter were predominantly confined to the hippocampus region of the brain in both animals. The inclusions tested α-synuclein-negative by immunohistochemistry, α-synuclein-positive with PAS, GMS, and Bielschowsky’s staining; and diastase-resistant with central basophilic cores and faintly radiating peripheral lines. Ultrastructural examination of the affected areas of the hippocampus showed non-membrane-bound aggregates of asymmetrically branching filaments that bifurcated regularly, consistent with PGBs in both animals. Additionally, α-synuclein immunopositivity was noted in the different regions of the hippocampus with accumulations of small granules ultrastructurally distinct from PGBs and morphologically compatible with alpha-synucleinopathy (Lewy body). The apparent blindness found in these moose could be related to an injury associated with secondary bacterial invasion; however, an accumulation of neurotoxicants (PGBs and α-synuclein) in retinal ganglions cells could also be the cause. This is the first report demonstrating Lafora disease with concurrent alpha-synucleinopathy (Lewy body neuropathy) in a non-domesticated animal.
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Moretto E, Stuart S, Surana S, Vargas JNS, Schiavo G. The Role of Extracellular Matrix Components in the Spreading of Pathological Protein Aggregates. Front Cell Neurosci 2022; 16:844211. [PMID: 35573838 PMCID: PMC9100790 DOI: 10.3389/fncel.2022.844211] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2021] [Accepted: 03/08/2022] [Indexed: 11/23/2022] Open
Abstract
Several neurodegenerative diseases are characterized by the accumulation of aggregated misfolded proteins. These pathological agents have been suggested to propagate in the brain via mechanisms similar to that observed for the prion protein, where a misfolded variant is transferred from an affected brain region to a healthy one, thereby inducing the misfolding and/or aggregation of correctly folded copies. This process has been characterized for several proteins, such as α-synuclein, tau, amyloid beta (Aβ) and less extensively for huntingtin and TDP-43. α-synuclein, tau, TDP-43 and huntingtin are intracellular proteins, and their aggregates are located in the cytosol or nucleus of neurons. They have been shown to spread between cells and this event occurs, at least partially, via secretion of these protein aggregates in the extracellular space followed by re-uptake. Conversely, Aβ aggregates are found mainly extracellularly, and their spreading occurs in the extracellular space between brain regions. Due to the inherent nature of their spreading modalities, these proteins are exposed to components of the extracellular matrix (ECM), including glycans, proteases and core matrix proteins. These ECM components can interact with or process pathological misfolded proteins, potentially changing their properties and thus regulating their spreading capabilities. Here, we present an overview of the documented roles of ECM components in the spreading of pathological protein aggregates in neurodegenerative diseases with the objective of identifying the current gaps in knowledge and stimulating further research in the field. This could potentially lead to the identification of druggable targets to slow down the spreading and/or progression of these pathologies.
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Affiliation(s)
- Edoardo Moretto
- Institute of Neuroscience, National Research Council, CNR, Milan, Italy
- UK Dementia Research Institute, University College London, London, United Kingdom
- Department of Neuromuscular Diseases, Queen Square Institute of Neurology, University College London, London, United Kingdom
- *Correspondence: Edoardo Moretto,
| | - Skye Stuart
- UK Dementia Research Institute, University College London, London, United Kingdom
- Department of Neuromuscular Diseases, Queen Square Institute of Neurology, University College London, London, United Kingdom
| | - Sunaina Surana
- UK Dementia Research Institute, University College London, London, United Kingdom
- Department of Neuromuscular Diseases, Queen Square Institute of Neurology, University College London, London, United Kingdom
- UCL Queen Square Motor Neuron Disease Centre, University College London, London, United Kingdom
| | - Jose Norberto S. Vargas
- UK Dementia Research Institute, University College London, London, United Kingdom
- Department of Neuromuscular Diseases, Queen Square Institute of Neurology, University College London, London, United Kingdom
- UCL Queen Square Motor Neuron Disease Centre, University College London, London, United Kingdom
| | - Giampietro Schiavo
- UK Dementia Research Institute, University College London, London, United Kingdom
- Department of Neuromuscular Diseases, Queen Square Institute of Neurology, University College London, London, United Kingdom
- UCL Queen Square Motor Neuron Disease Centre, University College London, London, United Kingdom
- Giampietro Schiavo,
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Huang S, Mo X, Wang J, Ye X, Yu H, Liu Y. α-Synuclein phase separation and amyloid aggregation are modulated by C-terminal truncations. FEBS Lett 2022; 596:1388-1400. [PMID: 35485974 DOI: 10.1002/1873-3468.14361] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2022] [Revised: 04/10/2022] [Accepted: 04/16/2022] [Indexed: 11/11/2022]
Abstract
The aggregation of α-synuclein (α-Syn) is a key pathological hallmark of Parkinson's disease (PD). α-Syn undergoes liquid-liquid phase separation (LLPS) to drive amyloid aggregation. How the LLPS of α-Syn is regulated remains largely unknown. Here, we discovered that the C-terminal region modulates α-Syn phase separation through electrostatic interactions. The wild-type (WT) and PD disease-related truncated α-Syn can co-exist in the condensates. The truncated α-Syn could dramatically promote WT α-Syn phase separation. Further studies demonstrated that the truncated α-Syn accelerated WT α-Syn turning to amyloid aggregates by modulation of phase separation. Together, our findings disclose the role of the C-terminal domain in the LLPS of α-Syn and pave the path for understanding the mechanism of truncated α-Syn in PD pathology.
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Affiliation(s)
- Shuai Huang
- Jiangsu Key Laboratory for Molecular and Medical Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing, 210023, China
| | - Xiaoli Mo
- Biology Department, Clark University, Worcester, Massachusetts, 01610, USA
| | - Jieyi Wang
- Jiangsu Key Laboratory for Molecular and Medical Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing, 210023, China
| | - Xinyi Ye
- Jiangsu Key Laboratory for Molecular and Medical Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing, 210023, China
| | - Haijia Yu
- Jiangsu Key Laboratory for Molecular and Medical Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing, 210023, China
| | - Yinghui Liu
- Jiangsu Key Laboratory for Molecular and Medical Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing, 210023, China
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Mechanisms of enhanced aggregation and fibril formation of Parkinson's disease-related variants of α-synuclein. Sci Rep 2022; 12:6770. [PMID: 35474118 PMCID: PMC9043213 DOI: 10.1038/s41598-022-10789-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2021] [Accepted: 04/08/2022] [Indexed: 12/18/2022] Open
Abstract
Aggregation of α-synuclein (α-syn) into amyloid fibrils is closely associated with Parkinson’s disease (PD). Familial mutations or posttranslational truncations in α-syn are known as risk factor for PD. Here, we examined the effects of the PD-related A30P or A53T point mutation and C-terminal 123–140 or 104–140 truncation on the aggregating property of α-syn based on the kinetic and thermodynamic analyses. Thioflavin T fluorescence measurements indicated that A53T, Δ123‒140, and Δ104–140 variants aggregated faster than WT α-syn, in which the A53T mutation markedly increases nucleation rate whereas the Δ123‒140 or Δ104‒140 truncation significantly increases both nucleation and fibril elongation rates. Ultracentrifugation and western blotting analyses demonstrated that these mutations or truncations promote the conversion of monomer to aggregated forms of α-syn. Analysis of the dependence of aggregation reaction of α-syn variants on the monomer concentration suggested that the A53T mutation enhances conversion of monomers to amyloid nuclei whereas the C-terminal truncations, especially the Δ104–140, enhance autocatalytic aggregation on existing fibrils. In addition, thermodynamic analysis of the kinetics of nucleation and fibril elongation of α-syn variants indicated that both nucleation and fibril elongation of WT α-syn are enthalpically and entropically unfavorable. Interestingly, the unfavorable activation enthalpy of nucleation greatly decreases for the A53T and becomes reversed in sign for the C-terminally truncated variants. Taken together, our results indicate that the A53T mutation and the C-terminal truncation enhance α-syn aggregation by reducing unfavorable activation enthalpy of nucleation, and the C-terminal truncation further triggers the autocatalytic fibril elongation on the fibril surfaces.
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Fan HF, Chen WL, Chen YZ, Huang JW, Shen YX. Change in the Oligomeric State of α-Synuclein Variants in Living Cells. ACS Chem Neurosci 2022; 13:1143-1164. [PMID: 35394271 DOI: 10.1021/acschemneuro.1c00646] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
The accumulation of β-sheet-rich α-synuclein (α-Syn) protein in human brain cells is a pathological hallmark of Parkinson's disease (PD). Moreover, it has been reported that familial PD mutations (A30P, E46K, H50Q, G51D, and A53T) accumulate at an accelerated rate both in vivo and in vitro. In addition, accumulations of various C-terminal α-Syn truncations, such as C-terminal-truncated N103 α-synuclein (N103), were found in an aggregated form in the brain tissue of PD patients. Fluorescent protein-tagged wild-type α-Syn, A30P, E46K, H50Q, G51D, A53T, and N103 were transfected into HEK293T and SHSY5Y cells, and their diffusion behaviors were investigated with a custom-built fluorescence microscope system. Based on our experimental results, the oligomerization of α-Syn is a time-dependent process in both HEK293T and SHSY5Y cells, and the oligomer state approaches a plateau after 48 h of transfection. The change in the oligomeric state of E46K, H50Q, and G51D exhibited a similar trend to the wild type at a lower concentration but became intense at a higher concentration. A53T and N103 possess smaller diffusion coefficients than wild-type α-synuclein and other family PD mutations, indicating that these two mutants could form higher oligomeric states or stronger interactions in HEK293T and SHSY5Y cells. In contrast, the smallest oligomer and the lowest intracellular interaction among all investigated α-Syn variants were found for A30P. These phenomena indicated the presence of different pathogeneses among familial PD mutants and C-terminal α-Syn truncations.
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Affiliation(s)
- Hsiu-Fang Fan
- Institute of Medical Science and Technology, National Sun Yat-sen University, No. 70 Lien-hai Road, Kaohsiung 80424, Kaohsiung 804, Taiwan
- Department of Chemistry, National Sun Yat-sen University, No. 70 Lien-hai Road, Kaohsiung 80424, Kaohsiung 804, Taiwan
- Aerosol Science Research Center, National Sun Yat-sen University, No. 70 Lien-hai Road, Kaohsiung 80424, Kaohsiung 804, Taiwan
| | - Wen-Ling Chen
- Department of Life Sciences and Institute of Genome Sciences, National Yang-Ming University, No. 155, Section 2, Linong Street, Taipei 112, Taiwan
| | - Yan-Zhow Chen
- Department of Life Sciences and Institute of Genome Sciences, National Yang-Ming University, No. 155, Section 2, Linong Street, Taipei 112, Taiwan
| | - Jian-Wei Huang
- Department of Chemistry, National Sun Yat-sen University, No. 70 Lien-hai Road, Kaohsiung 80424, Kaohsiung 804, Taiwan
| | - Yu-Xin Shen
- Department of Chemistry, National Sun Yat-sen University, No. 70 Lien-hai Road, Kaohsiung 80424, Kaohsiung 804, Taiwan
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Lau D, Magnan C, Hill K, Cooper A, Gambin Y, Sierecki E. Single Molecule Fingerprinting Reveals Different Amplification Properties of α-Synuclein Oligomers and Preformed Fibrils in Seeding Assay. ACS Chem Neurosci 2022; 13:883-896. [PMID: 35286811 PMCID: PMC8990999 DOI: 10.1021/acschemneuro.1c00553] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
The quantification of α-synuclein aggregates has emerged as a promising biomarker for synucleinopathies. Assays that amplify and detect such aggregates have revealed the presence of seeding-competent species in biosamples of patients diagnosed with Parkinson's disease. However, multiple species, such as oligomers and amyloid fibrils, are formed during the aggregation of α-synuclein; these species are likely to coexist in biological samples, and thus it remains unclear which species(s) are contributing to the signal detected in seeding assays. To identify individual contributions to the amplification process, recombinant oligomers and preformed fibrils were produced and purified to characterize their individual biochemical and seeding potential. Here, we used single molecule spectroscopy to track the formation and purification of oligomers and fibrils at the single particle level and compare their respective seeding potential in an amplification assay. Single molecule detection validates that size-exclusion chromatography efficiently separates oligomers from fibrils. Oligomers were found to be seeding-competent, but our results reveal that their seeding behavior is very different compared to that of preformed fibrils, in our amplification assay. Overall, our data suggest that even a low number of preformed fibrils present in biosamples is likely to dominate the response in seeding assays.
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Affiliation(s)
- Derrick Lau
- EMBL Australia Node for Single Molecule Sciences and School of Medical Sciences, Faculty of Medicine, the University of New South Wales, Sydney, New South Wales 2052, Australia
| | - Chloé Magnan
- EMBL Australia Node for Single Molecule Sciences and School of Medical Sciences, Faculty of Medicine, the University of New South Wales, Sydney, New South Wales 2052, Australia
| | - Kathryn Hill
- The Australian Parkinson’s Mission, The Garvan Institute of Medical Research, Darlinghurst, New South Wales 2010, Australia
| | - Antony Cooper
- The Australian Parkinson’s Mission, The Garvan Institute of Medical Research, Darlinghurst, New South Wales 2010, Australia
- St Vincent’s Clinical School, UNSW Sydney, Darlinghurst, New South Wales 2010, Australia
| | - Yann Gambin
- EMBL Australia Node for Single Molecule Sciences and School of Medical Sciences, Faculty of Medicine, the University of New South Wales, Sydney, New South Wales 2052, Australia
| | - Emma Sierecki
- EMBL Australia Node for Single Molecule Sciences and School of Medical Sciences, Faculty of Medicine, the University of New South Wales, Sydney, New South Wales 2052, Australia
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Pons ML, Loftus N, Vialaret J, Moreau S, Lehmann S, Hirtz C. Proteomics Challenges for the Assessment of Synuclein Proteoforms as Clinical Biomarkers in Parkinson’s Disease. Front Aging Neurosci 2022; 14:818606. [PMID: 35431896 PMCID: PMC9009522 DOI: 10.3389/fnagi.2022.818606] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Accepted: 03/09/2022] [Indexed: 11/13/2022] Open
Abstract
Parkinson’s disease is a complex neurodegenerative disorder resulting in a multifaceted clinical presentation which includes bradykinesia combined with either rest tremor, rigidity, or both, as well as many non-motor symptoms. The motor features of the disorder are associated with the pathological form of alpha synuclein aggregates and fibrils in Lewy bodies and loss of dopaminergic neurons in the substantia nigra. Parkinson’s disease is increasingly considered as a group of underlying disorders with unique genetic, biological, and molecular abnormalities that are likely to respond differentially to a given therapeutic approach. For this reason, it is clinically challenging to treat and at present, no therapy can slow down or arrest the progression of Parkinson’s disease. There is a clear unmet clinical need to develop reliable diagnostic and prognostic biomarkers. When disease-modifying treatments become available, prognostic biomarkers are required to support a definitive diagnosis and clinical intervention during the long prodromal period as no clinical implications or symptoms are observed. Robust diagnostic biomarkers would also be useful to monitor treatment response. Potential biomarkers for the sporadic form of Parkinson’s disease have mostly included synuclein species (monomer, oligomer, phosphorylated, Lewy Body enriched fraction and isoforms). In this review, we consider the analysis of synuclein and its proteoforms in biological samples using proteomics techniques (immunoassay and mass spectrometry) applied to neurodegenerative disease research.
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Affiliation(s)
- Marie-Laure Pons
- IRMB-PPC, INM, CHU Montpellier, INSERM, CNRS, Université de Montpellier, Montpellier, France
- Shimadzu Corporation, Duisburg, Germany
- *Correspondence: Marie-Laure Pons,
| | - Neil Loftus
- Shimadzu Corporation, Manchester, United Kingdom
| | - Jerome Vialaret
- IRMB-PPC, INM, CHU Montpellier, INSERM, CNRS, Université de Montpellier, Montpellier, France
| | | | - Sylvain Lehmann
- IRMB-PPC, INM, CHU Montpellier, INSERM, CNRS, Université de Montpellier, Montpellier, France
| | - Christophe Hirtz
- IRMB-PPC, INM, CHU Montpellier, INSERM, CNRS, Université de Montpellier, Montpellier, France
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Spatiotemporal modulations in heterotypic condensates of prion and α-synuclein control phase transitions and amyloid conversion. Nat Commun 2022; 13:1154. [PMID: 35241680 PMCID: PMC8894376 DOI: 10.1038/s41467-022-28797-5] [Citation(s) in RCA: 36] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2021] [Accepted: 02/10/2022] [Indexed: 12/30/2022] Open
Abstract
Biomolecular condensation via liquid-liquid phase separation of proteins and nucleic acids is associated with a range of critical cellular functions and neurodegenerative diseases. Here, we demonstrate that complex coacervation of the prion protein and α-synuclein within narrow stoichiometry results in the formation of highly dynamic, reversible, thermo-responsive liquid droplets via domain-specific electrostatic interactions between the positively-charged intrinsically disordered N-terminal segment of prion and the acidic C-terminal tail of α-synuclein. The addition of RNA to these coacervates yields multiphasic, vesicle-like, hollow condensates. Picosecond time-resolved measurements revealed the presence of transient electrostatic nanoclusters that are stable on the nanosecond timescale and can undergo breaking-and-making of interactions on slower timescales giving rise to a liquid-like behavior in the mesoscopic regime. The liquid-to-solid transition drives a rapid conversion of complex coacervates into heterotypic amyloids. Our results suggest that synergistic prion-α-synuclein interactions within condensates provide mechanistic underpinnings of their physiological role and overlapping neuropathological features. The authors show that prion protein and α-synuclein undergo phase separation through domain-specific electrostatic interactions. These complex coacervates possess electrostatic nanoclusters and can convert into multiphasic condensates and amyloids.
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Chen R, Gu X, Wang X. α-Synuclein in Parkinson's disease and advances in detection. Clin Chim Acta 2022; 529:76-86. [PMID: 35176268 DOI: 10.1016/j.cca.2022.02.006] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Revised: 02/08/2022] [Accepted: 02/10/2022] [Indexed: 12/26/2022]
Abstract
Parkinson's disease (PD) is a threatening neurodegenerative disorder that seriously affects patients' life quality. Substantial evidence links the overexpression and abnormal aggregation of alpha-synuclein (α-Syn) to PD. α-Syn has been identified as a characteristic biomarker of PD, which indicates its great value of diagnosis and designing effective therapeutic strategy. This article systematically summarizes the pathogenic process of α-Syn based on recent researches, outlines and compares commonly used analysis and detection technologies of α-Syn. Specifically, the detection of α-Syn by new electrochemical, photochemical, and crystal biosensors is mainly examined. Furthermore, the speculation of future study orientation is discussed, which provides reference for the further research and application of α-Syn as biomarker.
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Affiliation(s)
- Rong Chen
- School of Medicine, Southeast University, Nanjing 210009, China
| | - Xuan Gu
- Key Laboratory of Environmental Medicine Engineering of Ministry of Education, School of Public Health, Southeast University, Nanjing 210009, China
| | - Xiaoying Wang
- Key Laboratory of Environmental Medicine Engineering of Ministry of Education, School of Public Health, Southeast University, Nanjing 210009, China.
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Farzadfard A, Pedersen JN, Meisl G, Somavarapu AK, Alam P, Goksøyr L, Nielsen MA, Sander AF, Knowles TPJ, Pedersen JS, Otzen DE. The C-terminal tail of α-synuclein protects against aggregate replication but is critical for oligomerization. Commun Biol 2022; 5:123. [PMID: 35145226 PMCID: PMC8831632 DOI: 10.1038/s42003-022-03059-8] [Citation(s) in RCA: 29] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Accepted: 01/18/2022] [Indexed: 12/16/2022] Open
Abstract
Aggregation of the 140-residue protein α-synuclein (αSN) is a key factor in the etiology of Parkinson’s disease. Although the intensely anionic C-terminal domain (CTD) of αSN does not form part of the amyloid core region or affect membrane binding ability, truncation or reduction of charges in the CTD promotes fibrillation through as yet unknown mechanisms. Here, we study stepwise truncated CTDs and identify a threshold region around residue 121; constructs shorter than this dramatically increase their fibrillation tendency. Remarkably, these effects persist even when as little as 10% of the truncated variant is mixed with the full-length protein. Increased fibrillation can be explained by a substantial increase in self-replication, most likely via fragmentation. Paradoxically, truncation also suppresses toxic oligomer formation, and oligomers that can be formed by chemical modification show reduced membrane affinity and cytotoxicity. These remarkable changes correlate to the loss of negative electrostatic potential in the CTD and highlight a double-edged electrostatic safety guard. Farzadfard et al. present a comprehensive analysis of a range of C-terminal truncations of aSN, linking the importance of high C-terminus charge for decreased fibrillation rates. The ability to formation oligomers, to disrupt synthetic vesicles and cell toxicity was reduced with truncated aSN, aiding in understanding of the intramolecular interactions of aSN which promote/inhibit aggregation.
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Affiliation(s)
- Azad Farzadfard
- Interdisciplinary Nanoscience Center (iNANO), Aarhus University, Gustav Wieds Vej 14, 8000, Aarhus C, Denmark.,School of Biology, College of Science, University of Tehran, Tehran, Iran
| | - Jannik Nedergaard Pedersen
- Interdisciplinary Nanoscience Center (iNANO), Aarhus University, Gustav Wieds Vej 14, 8000, Aarhus C, Denmark
| | - Georg Meisl
- Yusuf Hamied Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, UK
| | - Arun Kumar Somavarapu
- Interdisciplinary Nanoscience Center (iNANO), Aarhus University, Gustav Wieds Vej 14, 8000, Aarhus C, Denmark
| | - Parvez Alam
- Interdisciplinary Nanoscience Center (iNANO), Aarhus University, Gustav Wieds Vej 14, 8000, Aarhus C, Denmark.,Department of Biomedicine, Aarhus University, 8000, Aarhus C, Denmark
| | - Louise Goksøyr
- Centre for Medical Parasitology at the Department of Immunology and Microbiology, University of Copenhagen, Blegdamsvej 3B, 2200, Copenhagen N, Denmark
| | - Morten Agertoug Nielsen
- Centre for Medical Parasitology at the Department of Immunology and Microbiology, University of Copenhagen, Blegdamsvej 3B, 2200, Copenhagen N, Denmark
| | - Adam Frederik Sander
- Centre for Medical Parasitology at the Department of Immunology and Microbiology, University of Copenhagen, Blegdamsvej 3B, 2200, Copenhagen N, Denmark
| | - Tuomas P J Knowles
- Yusuf Hamied Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, UK.,Cavendish Laboratory, University of Cambridge, J J Thomson Avenue, Cambridge, CB3 0HE, UK
| | - Jan Skov Pedersen
- Interdisciplinary Nanoscience Center (iNANO), Aarhus University, Gustav Wieds Vej 14, 8000, Aarhus C, Denmark.,Department of Chemistry, Aarhus University, Langelandsgade 140, 8000, Aarhus C, Denmark
| | - Daniel Erik Otzen
- Interdisciplinary Nanoscience Center (iNANO), Aarhus University, Gustav Wieds Vej 14, 8000, Aarhus C, Denmark. .,Department of Molecular Biology and Genetics, Gustav Wieds Vej 10C, 8000, Aarhus C, Denmark.
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63
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Storey CL, Williams RSB, Fisher PR, Annesley SJ. Dictyostelium discoideum: A Model System for Neurological Disorders. Cells 2022; 11:cells11030463. [PMID: 35159273 PMCID: PMC8833889 DOI: 10.3390/cells11030463] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Revised: 01/23/2022] [Accepted: 01/24/2022] [Indexed: 12/14/2022] Open
Abstract
Background: The incidence of neurological disorders is increasing due to population growth and extended life expectancy. Despite advances in the understanding of these disorders, curative strategies for treatment have not yet eventuated. In part, this is due to the complexities of the disorders and a lack of identification of their specific underlying pathologies. Dictyostelium discoideum has provided a useful, simple model to aid in unraveling the complex pathological characteristics of neurological disorders including Alzheimer’s disease, Parkinson’s disease, Huntington’s disease, neuronal ceroid lipofuscinoses and lissencephaly. In addition, D. discoideum has proven to be an innovative model for pharmaceutical research in the neurological field. Scope of review: This review describes the contributions of D. discoideum in the field of neurological research. The continued exploration of proteins implicated in neurological disorders in D. discoideum may elucidate their pathological roles and fast-track curative therapeutics.
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Affiliation(s)
- Claire Louise Storey
- Department of Microbiology, Anatomy, Physiology and Pharmacology, La Trobe University, Bundoora 3086, Australia; (C.L.S.); (P.R.F.)
| | - Robin Simon Brooke Williams
- Centre for Biomedical Sciences, School of Biological Sciences, Royal Holloway University of London, Egham TW20 0EX, UK;
| | - Paul Robert Fisher
- Department of Microbiology, Anatomy, Physiology and Pharmacology, La Trobe University, Bundoora 3086, Australia; (C.L.S.); (P.R.F.)
| | - Sarah Jane Annesley
- Department of Microbiology, Anatomy, Physiology and Pharmacology, La Trobe University, Bundoora 3086, Australia; (C.L.S.); (P.R.F.)
- Correspondence: ; Tel.: +61-394-791-412
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64
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Spathopoulou A, Edenhofer F, Fellner L. Targeting α-Synuclein in Parkinson's Disease by Induced Pluripotent Stem Cell Models. Front Neurol 2022; 12:786835. [PMID: 35145469 PMCID: PMC8821105 DOI: 10.3389/fneur.2021.786835] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Accepted: 12/24/2021] [Indexed: 11/22/2022] Open
Abstract
Parkinson's disease (PD) is a progressive, neurodegenerative disorder characterized by motor and non-motor symptoms. To date, no specific treatment to halt disease progression is available, only medication to alleviate symptoms can be prescribed. The main pathological hallmark of PD is the development of neuronal inclusions, positive for α-synuclein (α-syn), which are termed Lewy bodies (LBs) or Lewy neurites. However, the cause of the inclusion formation and the loss of neurons remain largely elusive. Various genetic determinants were reported to be involved in PD etiology, including SNCA, DJ-1, PRKN, PINK1, LRRK2, and GBA. Comprehensive insights into pathophysiology of PD critically depend on appropriate models. However, conventional model organisms fall short to faithfully recapitulate some features of this complex disease and as a matter-of-fact access to physiological tissue is limiting. The development of disease models replicating PD that are close to human physiology and dynamic enough to analyze the underlying molecular mechanisms of disease initiation and progression, as well as the generation of new treatment options, is an important and overdue step. Recently, the establishment of induced pluripotent stem cell (iPSC)-derived neural models, particularly from genetic PD-variants, developed into a promising strategy to investigate the molecular mechanisms regarding formation of inclusions and neurodegeneration. As these iPSC-derived neurons can be generated from accessible biopsied samples of PD patients, they carry pathological alterations and enable the possibility to analyze the differences compared to healthy neurons. This review focuses on iPSC models carrying genetic PD-variants of α-syn that will be especially helpful in elucidating the pathophysiological mechanisms of PD. Furthermore, we discuss how iPSC models can be instrumental in identifying cellular targets, potentially leading to the development of new therapeutic treatments. We will outline the enormous potential, but also discuss the limitations of iPSC-based α-syn models.
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65
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Murakami K, Izuo N, Bitan G. Aptamers targeting amyloidogenic proteins and their emerging role in neurodegenerative diseases. J Biol Chem 2022; 298:101478. [PMID: 34896392 PMCID: PMC8728582 DOI: 10.1016/j.jbc.2021.101478] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Revised: 11/24/2021] [Accepted: 12/02/2021] [Indexed: 01/08/2023] Open
Abstract
Aptamers are oligonucleotides selected from large pools of random sequences based on their affinity for bioactive molecules and are used in similar ways to antibodies. Aptamers provide several advantages over antibodies, including their small size, facile, large-scale chemical synthesis, high stability, and low immunogenicity. Amyloidogenic proteins, whose aggregation is relevant to neurodegenerative diseases, such as Alzheimer's, Parkinson's, and prion diseases, are among the most challenging targets for aptamer development due to their conformational instability and heterogeneity, the same characteristics that make drug development against amyloidogenic proteins difficult. Recently, chemical tethering of aptagens (equivalent to antigens) and advances in high-throughput sequencing-based analysis have been used to overcome some of these challenges. In addition, internalization technologies using fusion to cellular receptors and extracellular vesicles have facilitated central nervous system (CNS) aptamer delivery. In view of the development of these techniques and resources, here we review antiamyloid aptamers, highlighting preclinical application to CNS therapy.
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Affiliation(s)
- Kazuma Murakami
- Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Kyoto, Japan.
| | - Naotaka Izuo
- Laboratory of Pharmaceutical Therapy and Neuropharmacology, Faculty of Pharmaceutical Sciences, University of Toyama, Toyama, Japan
| | - Gal Bitan
- Department of Neurology, David Geffen School of Medicine, Brain Research Institute, and Molecular Biology Institute, University of California Los Angeles, Los Angeles, California, USA.
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66
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Li JL, Lin TY, Chen PL, Guo TN, Huang SY, Chen CH, Lin CH, Chan CC. Mitochondrial Function and Parkinson's Disease: From the Perspective of the Electron Transport Chain. Front Mol Neurosci 2021; 14:797833. [PMID: 34955747 PMCID: PMC8695848 DOI: 10.3389/fnmol.2021.797833] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2021] [Accepted: 11/18/2021] [Indexed: 12/21/2022] Open
Abstract
Parkinson’s disease (PD) is known as a mitochondrial disease. Some even regarded it specifically as a disorder of the complex I of the electron transport chain (ETC). The ETC is fundamental for mitochondrial energy production which is essential for neuronal health. In the past two decades, more than 20 PD-associated genes have been identified. Some are directly involved in mitochondrial functions, such as PRKN, PINK1, and DJ-1. While other PD-associate genes, such as LRRK2, SNCA, and GBA1, regulate lysosomal functions, lipid metabolism, or protein aggregation, some have been shown to indirectly affect the electron transport chain. The recent identification of CHCHD2 and UQCRC1 that are critical for functions of complex IV and complex III, respectively, provide direct evidence that PD is more than just a complex I disorder. Like UQCRC1 in preventing cytochrome c from release, functions of ETC proteins beyond oxidative phosphorylation might also contribute to the pathogenesis of PD.
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Affiliation(s)
- Jeng-Lin Li
- Department of Neurology, National Taiwan University Hospital, Taipei, Taiwan.,Division of Neurology, Department of Internal Medicine, Lo-Hsu Medical Foundation, Lotung Poh-Ai Hospital, Yilan County, Taiwan
| | - Tai-Yi Lin
- College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Po-Lin Chen
- National Institute of Infectious Diseases and Vaccinology, National Health Research Institutes, Miaoli County, Taiwan
| | - Ting-Ni Guo
- Graduate Institute of Physiology, National Taiwan University, Taipei, Taiwan
| | - Shu-Yi Huang
- Department of Medical Research, National Taiwan University Hospital, Taipei, Taiwan
| | - Chun-Hong Chen
- National Institute of Infectious Diseases and Vaccinology, National Health Research Institutes, Miaoli County, Taiwan
| | - Chin-Hsien Lin
- Department of Neurology, National Taiwan University Hospital, Taipei, Taiwan.,Department of Medical Research, National Taiwan University Hospital, Taipei, Taiwan
| | - Chih-Chiang Chan
- Graduate Institute of Physiology, National Taiwan University, Taipei, Taiwan
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67
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Targeted proteolytic products of τ and α-synuclein in neurodegeneration. Essays Biochem 2021; 65:905-912. [PMID: 34846537 PMCID: PMC8709889 DOI: 10.1042/ebc20210028] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Revised: 10/05/2021] [Accepted: 10/14/2021] [Indexed: 11/17/2022]
Abstract
CNS pathological inclusions comprising τ or α-synuclein (αSyn) define a spectrum of neurodegenerative diseases, and these can often present concurrently in the same individuals. The aggregation of both proteins is clearly associated with neurodegeneration and the deleterious properties of each protein is further supported by mutations in each gene (MAPT and SNCA, respectively) resulting in disease. The initiating events in most sporadic neurodegenerative diseases are still unclear but growing evidence suggests that the aberrant proteolytic cleavage of τ and αSyn results in products that can be toxic and/or initiate aggregation that can further spread by a prion-like mechanism. The accumulation of some of these cleavage products can further potentiate the progression of protein aggregation transmission and lead to their accumulation in peripheral biofluids such as cerebrospinal fluid (CSF) and blood. The future development of new tools to detect specific τ and αSyn abnormal cleavage products in peripheral biofluids could be useful biomarkers and better understand of the role of unique proteolytic activities could yield therapeutic interventions.
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68
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Gadhe L, Sakunthala A, Mukherjee S, Gahlot N, Bera R, Sawner AS, Kadu P, Maji SK. Intermediates of α-synuclein aggregation: Implications in Parkinson's disease pathogenesis. Biophys Chem 2021; 281:106736. [PMID: 34923391 DOI: 10.1016/j.bpc.2021.106736] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Revised: 11/27/2021] [Accepted: 11/27/2021] [Indexed: 12/11/2022]
Abstract
Cytoplasmic deposition of aberrantly misfolded α-synuclein (α-Syn) is a common feature of synucleinopathies, including Parkinson's disease (PD). However, the precise pathogenic mechanism of α-Syn in synucleinopathies remains elusive. Emerging evidence has suggested that α-Syn may contribute to PD pathogenesis in several ways; wherein the contribution of fibrillar species, for exerting toxicity and disease transmission, cannot be neglected. Further, the oligomeric species could be the most plausible neurotoxic species causing neuronal cell death. However, understanding the structural and molecular insights of these oligomers are very challenging due to the heterogeneity and transient nature of the species. In this review, we discuss the recent advancements in understanding the formation and role of α-Syn oligomers in PD pathogenesis. We also summarize the different types of α-Syn oligomeric species and potential mechanisms to exert neurotoxicity. Finally, we address the possible ways to target α-Syn as a promising approach against PD and the possible future directions.
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Affiliation(s)
- Laxmikant Gadhe
- Department of Biosciences and Bioengineering, IIT Bombay, Powai, Mumbai 400076, India
| | - Arunima Sakunthala
- Department of Biosciences and Bioengineering, IIT Bombay, Powai, Mumbai 400076, India
| | - Semanti Mukherjee
- Department of Biosciences and Bioengineering, IIT Bombay, Powai, Mumbai 400076, India
| | - Nitisha Gahlot
- Department of Biosciences and Bioengineering, IIT Bombay, Powai, Mumbai 400076, India
| | - Riya Bera
- Department of Biosciences and Bioengineering, IIT Bombay, Powai, Mumbai 400076, India
| | - Ajay Singh Sawner
- Department of Biosciences and Bioengineering, IIT Bombay, Powai, Mumbai 400076, India
| | - Pradeep Kadu
- Department of Biosciences and Bioengineering, IIT Bombay, Powai, Mumbai 400076, India
| | - Samir K Maji
- Department of Biosciences and Bioengineering, IIT Bombay, Powai, Mumbai 400076, India.
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69
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Franco A, Cuéllar J, Fernández-Higuero JÁ, de la Arada I, Orozco N, Valpuesta JM, Prado A, Muga A. Truncation-Driven Lateral Association of α-Synuclein Hinders Amyloid Clearance by the Hsp70-Based Disaggregase. Int J Mol Sci 2021; 22:ijms222312983. [PMID: 34884786 PMCID: PMC8657883 DOI: 10.3390/ijms222312983] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Revised: 11/28/2021] [Accepted: 11/28/2021] [Indexed: 11/16/2022] Open
Abstract
The aggregation of α-synuclein is the hallmark of a collective of neurodegenerative disorders known as synucleinopathies. The tendency to aggregate of this protein, the toxicity of its aggregation intermediates and the ability of the cellular protein quality control system to clear these intermediates seems to be regulated, among other factors, by post-translational modifications (PTMs). Among these modifications, we consider herein proteolysis at both the N- and C-terminal regions of α-synuclein as a factor that could modulate disassembly of toxic amyloids by the human disaggregase, a combination of the chaperones Hsc70, DnaJB1 and Apg2. We find that, in contrast to aggregates of the protein lacking the N-terminus, which can be solubilized as efficiently as those of the WT protein, the deletion of the C-terminal domain, either in a recombinant context or as a consequence of calpain treatment, impaired Hsc70-mediated amyloid disassembly. Progressive removal of the negative charges at the C-terminal region induces lateral association of fibrils and type B* oligomers, precluding chaperone action. We propose that truncation-driven aggregate clumping impairs the mechanical action of chaperones, which includes fast protofilament unzipping coupled to depolymerization. Inhibition of the chaperone-mediated clearance of C-truncated species could explain their exacerbated toxicity and higher propensity to deposit found in vivo.
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Affiliation(s)
- Aitor Franco
- Department of Biochemistry and Molecular Biology, Faculty of Science and Technology, University of the Basque Country (UPV/EHU), 48080 Bilbao, Spain; (A.F.); (J.Á.F.-H.); (A.P.)
- Instituto Biofisika (UPV/EHU, CSIC), University of the Basque Country, 48940 Leioa, Spain; (I.d.l.A.); (N.O.)
| | - Jorge Cuéllar
- Department of Macromolecular Structure, Centro Nacional de Biotecnología (CNB-CSIC), 28049 Madrid, Spain; (J.C.); (J.M.V.)
| | - José Ángel Fernández-Higuero
- Department of Biochemistry and Molecular Biology, Faculty of Science and Technology, University of the Basque Country (UPV/EHU), 48080 Bilbao, Spain; (A.F.); (J.Á.F.-H.); (A.P.)
- Instituto Biofisika (UPV/EHU, CSIC), University of the Basque Country, 48940 Leioa, Spain; (I.d.l.A.); (N.O.)
| | - Igor de la Arada
- Instituto Biofisika (UPV/EHU, CSIC), University of the Basque Country, 48940 Leioa, Spain; (I.d.l.A.); (N.O.)
| | - Natalia Orozco
- Instituto Biofisika (UPV/EHU, CSIC), University of the Basque Country, 48940 Leioa, Spain; (I.d.l.A.); (N.O.)
- Fundación Biofísica Bizkaia/Biofisika Bizkaia Fundazioa (FBB), Barrio Sarriena s/n, 48940 Leioa, Spain
| | - José M. Valpuesta
- Department of Macromolecular Structure, Centro Nacional de Biotecnología (CNB-CSIC), 28049 Madrid, Spain; (J.C.); (J.M.V.)
| | - Adelina Prado
- Department of Biochemistry and Molecular Biology, Faculty of Science and Technology, University of the Basque Country (UPV/EHU), 48080 Bilbao, Spain; (A.F.); (J.Á.F.-H.); (A.P.)
- Instituto Biofisika (UPV/EHU, CSIC), University of the Basque Country, 48940 Leioa, Spain; (I.d.l.A.); (N.O.)
| | - Arturo Muga
- Department of Biochemistry and Molecular Biology, Faculty of Science and Technology, University of the Basque Country (UPV/EHU), 48080 Bilbao, Spain; (A.F.); (J.Á.F.-H.); (A.P.)
- Instituto Biofisika (UPV/EHU, CSIC), University of the Basque Country, 48940 Leioa, Spain; (I.d.l.A.); (N.O.)
- Correspondence:
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70
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Padilla-Godínez FJ, Ramos-Acevedo R, Martínez-Becerril HA, Bernal-Conde LD, Garrido-Figueroa JF, Hiriart M, Hernández-López A, Argüero-Sánchez R, Callea F, Guerra-Crespo M. Protein Misfolding and Aggregation: The Relatedness between Parkinson's Disease and Hepatic Endoplasmic Reticulum Storage Disorders. Int J Mol Sci 2021; 22:ijms222212467. [PMID: 34830348 PMCID: PMC8619695 DOI: 10.3390/ijms222212467] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Revised: 10/18/2021] [Accepted: 10/19/2021] [Indexed: 12/21/2022] Open
Abstract
Dysfunction of cellular homeostasis can lead to misfolding of proteins thus acquiring conformations prone to polymerization into pathological aggregates. This process is associated with several disorders, including neurodegenerative diseases, such as Parkinson’s disease (PD), and endoplasmic reticulum storage disorders (ERSDs), like alpha-1-antitrypsin deficiency (AATD) and hereditary hypofibrinogenemia with hepatic storage (HHHS). Given the shared pathophysiological mechanisms involved in such conditions, it is necessary to deepen our understanding of the basic principles of misfolding and aggregation akin to these diseases which, although heterogeneous in symptomatology, present similarities that could lead to potential mutual treatments. Here, we review: (i) the pathological bases leading to misfolding and aggregation of proteins involved in PD, AATD, and HHHS: alpha-synuclein, alpha-1-antitrypsin, and fibrinogen, respectively, (ii) the evidence linking each protein aggregation to the stress mechanisms occurring in the endoplasmic reticulum (ER) of each pathology, (iii) a comparison of the mechanisms related to dysfunction of proteostasis and regulation of homeostasis between the diseases (such as the unfolded protein response and/or autophagy), (iv) and clinical perspectives regarding possible common treatments focused on improving the defensive responses to protein aggregation for diseases as different as PD, and ERSDs.
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Affiliation(s)
- Francisco J. Padilla-Godínez
- Neurosciences Division, Cell Physiology Institute, National Autonomous University of Mexico, Mexico City 04510, Mexico; (F.J.P.-G.); (R.R.-A.); (H.A.M.-B.); (L.D.B.-C.); (J.F.G.-F.); (M.H.)
- Regenerative Medicine Laboratory, Department of Surgery, Faculty of Medicine, National Autonomous University of Mexico, Mexico City 04510, Mexico; (A.H.-L.); (R.A.-S.)
| | - Rodrigo Ramos-Acevedo
- Neurosciences Division, Cell Physiology Institute, National Autonomous University of Mexico, Mexico City 04510, Mexico; (F.J.P.-G.); (R.R.-A.); (H.A.M.-B.); (L.D.B.-C.); (J.F.G.-F.); (M.H.)
- Regenerative Medicine Laboratory, Department of Surgery, Faculty of Medicine, National Autonomous University of Mexico, Mexico City 04510, Mexico; (A.H.-L.); (R.A.-S.)
| | - Hilda Angélica Martínez-Becerril
- Neurosciences Division, Cell Physiology Institute, National Autonomous University of Mexico, Mexico City 04510, Mexico; (F.J.P.-G.); (R.R.-A.); (H.A.M.-B.); (L.D.B.-C.); (J.F.G.-F.); (M.H.)
- Regenerative Medicine Laboratory, Department of Surgery, Faculty of Medicine, National Autonomous University of Mexico, Mexico City 04510, Mexico; (A.H.-L.); (R.A.-S.)
| | - Luis D. Bernal-Conde
- Neurosciences Division, Cell Physiology Institute, National Autonomous University of Mexico, Mexico City 04510, Mexico; (F.J.P.-G.); (R.R.-A.); (H.A.M.-B.); (L.D.B.-C.); (J.F.G.-F.); (M.H.)
- Regenerative Medicine Laboratory, Department of Surgery, Faculty of Medicine, National Autonomous University of Mexico, Mexico City 04510, Mexico; (A.H.-L.); (R.A.-S.)
| | - Jerónimo F. Garrido-Figueroa
- Neurosciences Division, Cell Physiology Institute, National Autonomous University of Mexico, Mexico City 04510, Mexico; (F.J.P.-G.); (R.R.-A.); (H.A.M.-B.); (L.D.B.-C.); (J.F.G.-F.); (M.H.)
- Regenerative Medicine Laboratory, Department of Surgery, Faculty of Medicine, National Autonomous University of Mexico, Mexico City 04510, Mexico; (A.H.-L.); (R.A.-S.)
| | - Marcia Hiriart
- Neurosciences Division, Cell Physiology Institute, National Autonomous University of Mexico, Mexico City 04510, Mexico; (F.J.P.-G.); (R.R.-A.); (H.A.M.-B.); (L.D.B.-C.); (J.F.G.-F.); (M.H.)
| | - Adriana Hernández-López
- Regenerative Medicine Laboratory, Department of Surgery, Faculty of Medicine, National Autonomous University of Mexico, Mexico City 04510, Mexico; (A.H.-L.); (R.A.-S.)
| | - Rubén Argüero-Sánchez
- Regenerative Medicine Laboratory, Department of Surgery, Faculty of Medicine, National Autonomous University of Mexico, Mexico City 04510, Mexico; (A.H.-L.); (R.A.-S.)
| | - Francesco Callea
- Department of Histopathology, Bugando Medical Centre, Catholic University of Healthy and Allied Sciences, Mwanza 1464, Tanzania;
| | - Magdalena Guerra-Crespo
- Neurosciences Division, Cell Physiology Institute, National Autonomous University of Mexico, Mexico City 04510, Mexico; (F.J.P.-G.); (R.R.-A.); (H.A.M.-B.); (L.D.B.-C.); (J.F.G.-F.); (M.H.)
- Regenerative Medicine Laboratory, Department of Surgery, Faculty of Medicine, National Autonomous University of Mexico, Mexico City 04510, Mexico; (A.H.-L.); (R.A.-S.)
- Correspondence:
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71
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Alpha-Synuclein and Cognitive Decline in Parkinson Disease. Life (Basel) 2021; 11:life11111239. [PMID: 34833115 PMCID: PMC8625417 DOI: 10.3390/life11111239] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2021] [Revised: 11/08/2021] [Accepted: 11/12/2021] [Indexed: 12/15/2022] Open
Abstract
Parkinson disease (PD) is the second most common neurodegenerative disorder in elderly people. It is characterized by the aggregation of misfolded alpha-synuclein throughout the nervous system. Aside from cardinal motor symptoms, cognitive impairment is one of the most disabling non-motor symptoms that occurs during the progression of the disease. The accumulation and spreading of alpha-synuclein pathology from the brainstem to limbic and neocortical structures is correlated with emerging cognitive decline in PD. This review summarizes the genetic and pathophysiologic relationship between alpha-synuclein and cognitive impairment in PD, together with potential areas of biomarker advancement.
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72
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Tian Y, He M, Pan L, Yuan X, Xiong M, Meng L, Yao Z, Yu Z, Ye K, Zhang Z. Transgenic Mice Expressing Human α-Synuclein 1-103 Fragment as a Novel Model of Parkinson's Disease. Front Aging Neurosci 2021; 13:760781. [PMID: 34744697 PMCID: PMC8569470 DOI: 10.3389/fnagi.2021.760781] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2021] [Accepted: 10/01/2021] [Indexed: 11/13/2022] Open
Abstract
Parkinson's disease (PD) is one of the most common neurodegenerative disorders. However, its cellular and molecular mechanisms still wrap in the mist. This is partially caused by the absence of appropriate animal models mimicking sporadic PD that constitutes the majority of cases. Previously, we reported that a cysteine protease, asparagine endopeptidase (AEP), is activated in an age-dependent manner, and cleaves α-synuclein in the brain of sporadic PD patients. The AEP-derived α-synuclein 1-103 fragment is required for the pathogenesis of PD. Thus, we designed and characterized a novel transgenic mouse line expressing α-synuclein 1-103 (designated N103 mice). This model shows an abundant accumulation of pathological α-synuclein in the central nervous system, loss of dopaminergic neurons in the substantia nigra, and progressive striatal synaptic degeneration. The N103 mice also manifest age-dependent PD-like behavioral impairments. Notably, the mice show weight loss and constipation, which are the common non-motor symptoms in PD. The RNA-sequencing analysis found that the transcriptomics pattern was extensively altered in N103 mice. In conclusion, the N103 mouse line, as a brand-new tool, might provide new insights into PD research.
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Affiliation(s)
- Ye Tian
- Department of Neurology, Renmin Hospital of Wuhan University, Wuhan, China
| | - Mingyang He
- Department of Neurology, Renmin Hospital of Wuhan University, Wuhan, China
| | - Lina Pan
- Department of Neurology, Renmin Hospital of Wuhan University, Wuhan, China
| | - Xin Yuan
- Department of Neurology, Renmin Hospital of Wuhan University, Wuhan, China
| | - Min Xiong
- Department of Neurology, Renmin Hospital of Wuhan University, Wuhan, China
| | - Lanxia Meng
- Department of Neurology, Renmin Hospital of Wuhan University, Wuhan, China
| | - Zhaohui Yao
- Department of Geriatrics, Renmin Hospital of Wuhan University, Wuhan, China
| | - Zhui Yu
- Department of Critical Care Medicine, Renmin Hospital of Wuhan University, Wuhan, China
| | - Keqiang Ye
- Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, GA, United States
| | - Zhentao Zhang
- Department of Neurology, Renmin Hospital of Wuhan University, Wuhan, China
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Unzipping the Secrets of Amyloid Disassembly by the Human Disaggregase. Cells 2021; 10:cells10102745. [PMID: 34685723 PMCID: PMC8534776 DOI: 10.3390/cells10102745] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2021] [Revised: 10/08/2021] [Accepted: 10/08/2021] [Indexed: 01/08/2023] Open
Abstract
Neurodegenerative diseases (NDs) are increasingly positioned as leading causes of global deaths. The accelerated aging of the population and its strong relationship with neurodegeneration forecast these pathologies as a huge global health problem in the upcoming years. In this scenario, there is an urgent need for understanding the basic molecular mechanisms associated with such diseases. A major molecular hallmark of most NDs is the accumulation of insoluble and toxic protein aggregates, known as amyloids, in extracellular or intracellular deposits. Here, we review the current knowledge on how molecular chaperones, and more specifically a ternary protein complex referred to as the human disaggregase, deals with amyloids. This machinery, composed of the constitutive Hsp70 (Hsc70), the class B J-protein DnaJB1 and the nucleotide exchange factor Apg2 (Hsp110), disassembles amyloids of α-synuclein implicated in Parkinson’s disease as well as of other disease-associated proteins such as tau and huntingtin. We highlight recent studies that have led to the dissection of the mechanism used by this chaperone system to perform its disaggregase activity. We also discuss whether this chaperone-mediated disassembly mechanism could be used to solubilize other amyloidogenic substrates. Finally, we evaluate the implications of the chaperone system in amyloid clearance and associated toxicity, which could be critical for the development of new therapies.
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74
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Erekat NS. Apoptosis and its therapeutic implications in neurodegenerative diseases. Clin Anat 2021; 35:65-78. [PMID: 34558138 DOI: 10.1002/ca.23792] [Citation(s) in RCA: 38] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2021] [Revised: 09/19/2021] [Accepted: 09/21/2021] [Indexed: 12/18/2022]
Abstract
Neurodegenerative disorders are characterized by progressive loss of particular populations of neurons. Apoptosis has been implicated in the pathogenesis of neurodegenerative diseases, including Parkinson disease, Alzheimer disease, Huntington disease, and amyotrophic lateral sclerosis. In this review, we focus on the existing notions relevant to comprehending the apoptotic death process, including the morphological features, mediators and regulators of cellular apoptosis. We also highlight the evidence of neuronal apoptotic death in Parkinson disease, Alzheimer disease, Huntington disease, and amyotrophic lateral sclerosis. Additionally, we present evidence of potential therapeutic agents that could modify the apoptotic pathway in the aforementioned neurodegenerative diseases and delay disease progression. Finally, we review the clinical trials that were conducted to evaluate the use of anti-apoptotic drugs in the treatment of the aforementioned neurodegenerative diseases, in order to highlight the essential need for early detection and intervention of neurodegenerative diseases in humans.
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Affiliation(s)
- Nour S Erekat
- Department of Anatomy, Faculty of Medicine, Jordan University of Science and Technology, Irbid, Jordan
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75
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Jellinger KA, Wenning GK, Stefanova N. Is Multiple System Atrophy a Prion-like Disorder? Int J Mol Sci 2021; 22:10093. [PMID: 34576255 PMCID: PMC8472631 DOI: 10.3390/ijms221810093] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Revised: 09/16/2021] [Accepted: 09/16/2021] [Indexed: 02/08/2023] Open
Abstract
Multiple system atrophy (MSA) is a rapidly progressive, fatal neurodegenerative disease of uncertain aetiology that belongs to the family of α-synucleinopathies. It clinically presents with parkinsonism, cerebellar, autonomic, and motor impairment in variable combinations. Pathological hallmarks are fibrillary α-synuclein (αSyn)-rich glial cytoplasmic inclusions (GCIs) mainly involving oligodendroglia and to a lesser extent neurons, inducing a multisystem neurodegeneration, glial activation, and widespread demyelinization. The neuronal αSyn pathology of MSA has molecular properties different from Lewy bodies in Parkinson's disease (PD), both of which could serve as a pool of αSyn (prion) seeds that could initiate and drive the pathogenesis of synucleinopathies. The molecular cascade leading to the "prion-like" transfer of "strains" of aggregated αSyn contributing to the progression of the disease is poorly understood, while some presented evidence that MSA is a prion disease. However, this hypothesis is difficult to reconcile with postmortem analysis of human brains and the fact that MSA-like pathology was induced by intracerebral inoculation of human MSA brain homogenates only in homozygous mutant 53T mice, without production of disease-specific GCIs, or with replication of MSA prions in primary astrocyte cultures from transgenic mice expressing human αSyn. Whereas recent intrastriatal injection of Lewy body-derived or synthetic human αSyn fibrils induced PD-like pathology including neuronal αSyn aggregates in macaques, no such transmission of αSyn pathology in non-human primates by MSA brain lysate has been reported until now. Given the similarities between αSyn and prions, there is a considerable debate whether they should be referred to as "prions", "prion-like", "prionoids", or something else. Here, the findings supporting the proposed nature of αSyn as a prion and its self-propagation through seeding as well as the transmissibility of neurodegenerative disorders are discussed. The proof of disease causation rests on the concordance of scientific evidence, none of which has provided convincing evidence for the classification of MSA as a prion disease or its human transmission until now.
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Affiliation(s)
| | - Gregor K. Wenning
- Division of Neurobiology, Department of Neurology, Medical University of Innsbruck, 6020 Innsbruck, Austria; (G.K.W.); (N.S.)
| | - Nadia Stefanova
- Division of Neurobiology, Department of Neurology, Medical University of Innsbruck, 6020 Innsbruck, Austria; (G.K.W.); (N.S.)
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76
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Parkinson's disease and the gut: Models of an emerging relationship. Acta Biomater 2021; 132:325-344. [PMID: 33857691 DOI: 10.1016/j.actbio.2021.03.071] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2020] [Revised: 03/25/2021] [Accepted: 03/30/2021] [Indexed: 12/17/2022]
Abstract
Parkinson's disease (PD) is a common neurodegenerative disease characterized by a progressive loss of fine motor function that impacts 1-2 out of 1,000 people. PD occurs predominately late in life and lacks a definitive biomarker for early detection. Recent cross-disciplinary progress has implicated the gut as a potential origin of PD pathogenesis. The gut-origin hypothesis has motivated research on gut PD pathology and transmission to the brain, especially during the prodromal stage (10-20 years before motor symptom onset). Early findings have revealed several possible triggers for Lewy pathology - the pathological hallmark of PD - in the gut, suggesting that microbiome and epithelial interactions may play a greater than appreciated role. But the mechanisms driving Lewy pathology and gut-brain transmission in PD remain unknown. Development of artificial α-Synuclein aggregates (α-Syn preformed fibrils) and animal disease models have recapitulated features of PD progression, enabling for the first time, controlled investigation of the gut-origin hypothesis. However, the role of specific cells in PD transmission, such as neurons, remains limited and requires in vitro models for controlled evaluation and perturbation. Human cell populations, three-dimensional organoids, and microfluidics as discovery platforms inch us closer to improving existing treatment for patients by providing platforms for discovery and screening. This review includes a discussion of PD pathology, conventional treatments, in vivo and in vitro models, and future directions. STATEMENT OF SIGNIFICANCE: Parkinson's Disease remains a common neurodegenerative disease with palliative versus causal treatments. Recently, the gut-origin hypothesis, where Parkinson's disease is thought to originate and spread from the gut to the brain, has gained traction as a field of investigation. However, despite the wealth of studies and innovative approaches to accelerate the field, there remains a need for in vitro tools to enable fundamental biological understanding of disease progression, and compound screening and efficacy. In this review, we present a historical perspective of Parkinson's Disease pathogenesis, detection, and conventional therapy, animal and human models investigating the gut-origin hypothesis, in vitro models to enable controlled discovery, and future outlooks for this blossoming field.
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77
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Cao Q, Boyer DR, Sawaya MR, Abskharon R, Saelices L, Nguyen BA, Lu J, Murray KA, Kandeel F, Eisenberg DS. Cryo-EM structures of hIAPP fibrils seeded by patient-extracted fibrils reveal new polymorphs and conserved fibril cores. Nat Struct Mol Biol 2021; 28:724-730. [PMID: 34518699 PMCID: PMC10396428 DOI: 10.1038/s41594-021-00646-x] [Citation(s) in RCA: 45] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Accepted: 07/20/2021] [Indexed: 02/07/2023]
Abstract
Amyloidosis of human islet amyloid polypeptide (hIAPP) is a pathological hallmark of type II diabetes (T2D), an epidemic afflicting nearly 10% of the world's population. To visualize disease-relevant hIAPP fibrils, we extracted amyloid fibrils from islet cells of a T2D donor and amplified their quantity by seeding synthetic hIAPP. Cryo-EM studies revealed four fibril polymorphic atomic structures. Their resemblance to four unseeded hIAPP fibrils varies from nearly identical (TW3) to non-existent (TW2). The diverse repertoire of hIAPP polymorphs appears to arise from three distinct protofilament cores entwined in different combinations. The structural distinctiveness of TW1, TW2 and TW4 suggests they may be faithful replications of the pathogenic seeds. If so, the structures determined here provide the most direct view yet of hIAPP amyloid fibrils formed during T2D.
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Affiliation(s)
- Qin Cao
- Departments of Chemistry and Biochemistry and Biological Chemistry, UCLA-DOE Institute, Molecular Biology Institute, and Howard Hughes Medical Institute, UCLA, Los Angeles, CA, USA.,Bio-X Institutes, Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders, Ministry of Education, Shanghai Jiao Tong University, Shanghai, China
| | - David R Boyer
- Departments of Chemistry and Biochemistry and Biological Chemistry, UCLA-DOE Institute, Molecular Biology Institute, and Howard Hughes Medical Institute, UCLA, Los Angeles, CA, USA
| | - Michael R Sawaya
- Departments of Chemistry and Biochemistry and Biological Chemistry, UCLA-DOE Institute, Molecular Biology Institute, and Howard Hughes Medical Institute, UCLA, Los Angeles, CA, USA
| | - Romany Abskharon
- Departments of Chemistry and Biochemistry and Biological Chemistry, UCLA-DOE Institute, Molecular Biology Institute, and Howard Hughes Medical Institute, UCLA, Los Angeles, CA, USA
| | - Lorena Saelices
- Departments of Chemistry and Biochemistry and Biological Chemistry, UCLA-DOE Institute, Molecular Biology Institute, and Howard Hughes Medical Institute, UCLA, Los Angeles, CA, USA.,Center for Alzheimer's and Neurodegenerative Diseases, Department of Biophysics, UT Southwestern Medical Center, Dallas, TX, USA
| | - Binh A Nguyen
- Departments of Chemistry and Biochemistry and Biological Chemistry, UCLA-DOE Institute, Molecular Biology Institute, and Howard Hughes Medical Institute, UCLA, Los Angeles, CA, USA.,Center for Alzheimer's and Neurodegenerative Diseases, Department of Biophysics, UT Southwestern Medical Center, Dallas, TX, USA
| | - Jiahui Lu
- Departments of Chemistry and Biochemistry and Biological Chemistry, UCLA-DOE Institute, Molecular Biology Institute, and Howard Hughes Medical Institute, UCLA, Los Angeles, CA, USA
| | - Kevin A Murray
- Departments of Chemistry and Biochemistry and Biological Chemistry, UCLA-DOE Institute, Molecular Biology Institute, and Howard Hughes Medical Institute, UCLA, Los Angeles, CA, USA
| | - Fouad Kandeel
- Department of Translational Research & Cellular Therapeutics, City of Hope, Duarte, CA, USA
| | - David S Eisenberg
- Departments of Chemistry and Biochemistry and Biological Chemistry, UCLA-DOE Institute, Molecular Biology Institute, and Howard Hughes Medical Institute, UCLA, Los Angeles, CA, USA.
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78
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Hartlage-Rübsamen M, Bluhm A, Moceri S, Machner L, Köppen J, Schenk M, Hilbrich I, Holzer M, Weidenfeller M, Richter F, Coras R, Serrano GE, Beach TG, Schilling S, von Hörsten S, Xiang W, Schulze A, Roßner S. A glutaminyl cyclase-catalyzed α-synuclein modification identified in human synucleinopathies. Acta Neuropathol 2021; 142:399-421. [PMID: 34309760 PMCID: PMC8357657 DOI: 10.1007/s00401-021-02349-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Revised: 07/13/2021] [Accepted: 07/13/2021] [Indexed: 12/22/2022]
Abstract
Parkinson’s disease (PD) is a progressive neurodegenerative disorder that is neuropathologically characterized by degeneration of dopaminergic neurons of the substantia nigra (SN) and formation of Lewy bodies and Lewy neurites composed of aggregated α-synuclein. Proteolysis of α-synuclein by matrix metalloproteinases was shown to facilitate its aggregation and to affect cell viability. One of the proteolysed fragments, Gln79-α-synuclein, possesses a glutamine residue at its N-terminus. We argue that glutaminyl cyclase (QC) may catalyze the pyroglutamate (pGlu)79-α-synuclein formation and, thereby, contribute to enhanced aggregation and compromised degradation of α-synuclein in human synucleinopathies. Here, the kinetic characteristics of Gln79-α-synuclein conversion into the pGlu-form by QC are shown using enzymatic assays and mass spectrometry. Thioflavin T assays and electron microscopy demonstrated a decreased potential of pGlu79-α-synuclein to form fibrils. However, size exclusion chromatography and cell viability assays revealed an increased propensity of pGlu79-α-synuclein to form oligomeric aggregates with high neurotoxicity. In brains of wild-type mice, QC and α-synuclein were co-expressed by dopaminergic SN neurons. Using a specific antibody against the pGlu-modified neo-epitope of α-synuclein, pGlu79-α-synuclein aggregates were detected in association with QC in brains of two transgenic mouse lines with human α-synuclein overexpression. In human brain samples of PD and dementia with Lewy body subjects, pGlu79-α-synuclein was shown to be present in SN neurons, in a number of Lewy bodies and in dystrophic neurites. Importantly, there was a spatial co-occurrence of pGlu79-α-synuclein with the enzyme QC in the human SN complex and a defined association of QC with neuropathological structures. We conclude that QC catalyzes the formation of oligomer-prone pGlu79-α-synuclein in human synucleinopathies, which may—in analogy to pGlu-Aβ peptides in Alzheimer’s disease—act as a seed for pathogenic protein aggregation.
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79
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McGlinchey RP, Ni X, Shadish JA, Jiang J, Lee JC. The N terminus of α-synuclein dictates fibril formation. Proc Natl Acad Sci U S A 2021; 118:e2023487118. [PMID: 34452994 PMCID: PMC8536336 DOI: 10.1073/pnas.2023487118] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2020] [Accepted: 07/09/2021] [Indexed: 12/23/2022] Open
Abstract
The generation of α-synuclein (α-syn) truncations from incomplete proteolysis plays a significant role in the pathogenesis of Parkinson's disease. It is well established that C-terminal truncations exhibit accelerated aggregation and serve as potent seeds in fibril propagation. In contrast, mechanistic understanding of N-terminal truncations remains ill defined. Previously, we found that disease-related C-terminal truncations resulted in increased fibrillar twist, accompanied by modest conformational changes in a more compact core, suggesting that the N-terminal region could be dictating fibril structure. Here, we examined three N-terminal truncations, in which deletions of 13-, 35-, and 40-residues in the N terminus modulated both aggregation kinetics and fibril morphologies. Cross-seeding experiments showed that out of the three variants, only ΔN13-α-syn (14‒140) fibrils were capable of accelerating full-length fibril formation, albeit slower than self-seeding. Interestingly, the reversed cross-seeding reactions with full-length seeds efficiently promoted all but ΔN40-α-syn (41-140). This behavior can be explained by the unique fibril structure that is adopted by 41-140 with two asymmetric protofilaments, which was determined by cryogenic electron microscopy. One protofilament resembles the previously characterized bent β-arch kernel, comprised of residues E46‒K96, whereas in the other protofilament, fewer residues (E61‒D98) are found, adopting an extended β-hairpin conformation that does not resemble other reported structures. An interfilament interface exists between residues K60‒F94 and Q62‒I88 with an intermolecular salt bridge between K80 and E83. Together, these results demonstrate a vital role for the N-terminal residues in α-syn fibril formation and structure, offering insights into the interplay of α-syn and its truncations.
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Affiliation(s)
- Ryan P McGlinchey
- Laboratory of Protein Conformation and Dynamics, Biochemistry and Biophysics Center, National Heart, Lung, and Blood Institute, Bethesda, MD 20892
| | - Xiaodan Ni
- Laboratory of Membrane Proteins and Structural Biology, Biochemistry and Biophysics Center, National Heart, Lung, and Blood Institute, Bethesda, MD 20892
| | - Jared A Shadish
- Laboratory of Protein Conformation and Dynamics, Biochemistry and Biophysics Center, National Heart, Lung, and Blood Institute, Bethesda, MD 20892
| | - Jiansen Jiang
- Laboratory of Membrane Proteins and Structural Biology, Biochemistry and Biophysics Center, National Heart, Lung, and Blood Institute, Bethesda, MD 20892
| | - Jennifer C Lee
- Laboratory of Protein Conformation and Dynamics, Biochemistry and Biophysics Center, National Heart, Lung, and Blood Institute, Bethesda, MD 20892;
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80
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Hass EW, Sorrentino ZA, Xia Y, Lloyd GM, Trojanowski JQ, Prokop S, Giasson BI. Disease-, region- and cell type specific diversity of α-synuclein carboxy terminal truncations in synucleinopathies. Acta Neuropathol Commun 2021; 9:146. [PMID: 34454615 PMCID: PMC8403399 DOI: 10.1186/s40478-021-01242-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2021] [Accepted: 08/08/2021] [Indexed: 12/14/2022] Open
Abstract
Synucleinopathies, including Parkinson's disease (PD), Lewy body dementia (LBD), Alzheimer's disease with amygdala restricted Lewy bodies (AD/ALB), and multiple system atrophy (MSA) comprise a spectrum of neurodegenerative disorders characterized by the presence of distinct pathological α-synuclein (αSyn) inclusions. Experimental and pathological studies support the notion that αSyn aggregates contribute to cellular demise and dysfunction with disease progression associated with a prion-like spread of αSyn aggregates via conformational templating. The initiating event(s) and factors that contribute to diverse forms of synucleinopathies remain poorly understood. A major post-translational modification of αSyn associated with pathological inclusions is a diverse array of specific truncations within the carboxy terminal region. While these modifications have been shown experimentally to induce and promote αSyn aggregation, little is known about their disease-, region- and cell type specific distribution. To this end, we generated a series of monoclonal antibodies specific to neo-epitopes in αSyn truncated after residues 103, 115, 119, 122, 125, and 129. Immunocytochemical investigations using these new tools revealed striking differences in the αSyn truncation pattern between different synucleinopathies, brain regions and specific cellular populations. In LBD, neuronal inclusions in the substantia nigra and amygdala were positive for αSyn cleaved after residues 103, 119, 122, and 125, but not 115. In contrast, in the same patients' brain αSyn cleaved at residue 115, as well as 103, 119 and 122 were abundant in the dorsal motor nucleus of the vagus. In patients with AD/ALB, these modifications were only weakly or not detected in amygdala αSyn inclusions. αSyn truncated at residues 103, 115, 119, and 125 was readily present in MSA glial cytoplasmic inclusions, but 122 cleaved αSyn was only weakly or not present. Conversely, MSA neuronal pathology in the pontine nuclei was strongly reactive to the αSyn x-122 neo-epitope but did not display any reactivity for αSyn 103 cleavage. These studies demonstrate significant disease-, region- and cell type specific differences in carboxy terminal αSyn processing associated with pathological inclusions that likely contributes to their distinct strain-like prion properties and promotes the diversity displayed in the degrees of these insidious diseases.
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Affiliation(s)
- Ethan W Hass
- Department of Neuroscience, College of Medicine, University of Florida, BMS J483/CTRND, 1275 Center Drive, Gainesville, FL, 32610, USA
- Center for Translational Research in Neurodegenerative Disease, College of Medicine, University of Florida, Gainesville, FL, 32610, USA
| | - Zachary A Sorrentino
- Department of Neuroscience, College of Medicine, University of Florida, BMS J483/CTRND, 1275 Center Drive, Gainesville, FL, 32610, USA
- Center for Translational Research in Neurodegenerative Disease, College of Medicine, University of Florida, Gainesville, FL, 32610, USA
| | - Yuxing Xia
- Department of Neuroscience, College of Medicine, University of Florida, BMS J483/CTRND, 1275 Center Drive, Gainesville, FL, 32610, USA
- Center for Translational Research in Neurodegenerative Disease, College of Medicine, University of Florida, Gainesville, FL, 32610, USA
| | - Grace M Lloyd
- Department of Neuroscience, College of Medicine, University of Florida, BMS J483/CTRND, 1275 Center Drive, Gainesville, FL, 32610, USA
- Center for Translational Research in Neurodegenerative Disease, College of Medicine, University of Florida, Gainesville, FL, 32610, USA
| | - John Q Trojanowski
- Department of Pathology and Laboratory Medicine, AD Center Core (ADCC), Center for Neurodegenerative Disease Research, PENN) School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Stefan Prokop
- Center for Translational Research in Neurodegenerative Disease, College of Medicine, University of Florida, Gainesville, FL, 32610, USA
- McKnight Brain Institute, College of Medicine, University of Florida, Gainesville, FL, 32610, USA
- Department of Pathology, College of Medicine, University of Florida, Gainesville, FL, 32610, USA
| | - Benoit I Giasson
- Department of Neuroscience, College of Medicine, University of Florida, BMS J483/CTRND, 1275 Center Drive, Gainesville, FL, 32610, USA.
- Center for Translational Research in Neurodegenerative Disease, College of Medicine, University of Florida, Gainesville, FL, 32610, USA.
- McKnight Brain Institute, College of Medicine, University of Florida, Gainesville, FL, 32610, USA.
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81
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Bell R, Vendruscolo M. Modulation of the Interactions Between α-Synuclein and Lipid Membranes by Post-translational Modifications. Front Neurol 2021; 12:661117. [PMID: 34335440 PMCID: PMC8319954 DOI: 10.3389/fneur.2021.661117] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2021] [Accepted: 05/18/2021] [Indexed: 12/14/2022] Open
Abstract
Parkinson's disease is characterised by the presence in brain tissue of aberrant inclusions known as Lewy bodies and Lewy neurites, which are deposits composed by α-synuclein and a variety of other cellular components, including in particular lipid membranes. The dysregulation of the balance between lipid homeostasis and α-synuclein homeostasis is therefore likely to be closely involved in the onset and progression of Parkinson's disease and related synucleinopathies. As our understanding of this balance is increasing, we describe recent advances in the characterisation of the role of post-translational modifications in modulating the interactions of α-synuclein with lipid membranes. We then discuss the impact of these advances on the development of novel diagnostic and therapeutic tools for synucleinopathies.
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Affiliation(s)
| | - Michele Vendruscolo
- Centre for Misfolding Disease, Department of Chemistry, University of Cambridge, Cambridge, United Kingdom
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82
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Lashuel HA. Rethinking protein aggregation and drug discovery in neurodegenerative diseases: Why we need to embrace complexity? Curr Opin Chem Biol 2021; 64:67-75. [PMID: 34174698 DOI: 10.1016/j.cbpa.2021.05.006] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Revised: 04/30/2021] [Accepted: 05/09/2021] [Indexed: 12/19/2022]
Abstract
More than a century has passed since pathological protein aggregates were first identified in the brains of patients with neurodegenerative diseases (NDDs). Yet, we still do not have effective therapies to treat or slow the progression of these devastating diseases or diagnostics for early detection and monitoring disease progression. Herein, I reflect on recent findings that are challenging traditional views about the composition, ultrastructural properties, and diversity of protein pathologies in the brain, their mechanisms of formation and how we investigate and model pathological aggregation processes in the laboratory today. This article is an invitation to embrace the complexity of proteinopathies as an essential step to understanding the molecular mechanisms underpinning NDDs and to advance translational research and drug discovery in NDDs.
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Affiliation(s)
- Hilal A Lashuel
- Laboratory of Molecular and Chemical Biology of Neurodegeneration, Brain Mind Institute, Ecole Polytechnique Fédérale de Lausanne, 1015, Lausanne, Switzerland.
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83
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Martinez Hernandez A, Silbern I, Geffers I, Tatenhorst L, Becker S, Urlaub H, Zweckstetter M, Griesinger C, Eichele G. Low-Expressing Synucleinopathy Mouse Models Based on Oligomer-Forming Mutations and C-Terminal Truncation of α-Synuclein. Front Neurosci 2021; 15:643391. [PMID: 34220415 PMCID: PMC8248494 DOI: 10.3389/fnins.2021.643391] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Accepted: 05/17/2021] [Indexed: 12/16/2022] Open
Abstract
α-synuclein (αSyn) is the main protein component of Lewy bodies, intracellular inclusions found in the brain of Parkinson's disease (PD) patients. Neurotoxic αSyn species are broadly modified post-translationally and, in patients with genetic forms of PD, carry genetically encoded amino acid substitutions. Mutations and C-terminal truncation can increase αSyn oligomerization and fibrillization. Although several genetic mouse models based on αSyn mutations and/or truncations exist, there is still a lack of mouse models for synucleinopathies not relying on overexpression. We report here two synucleinopathy mouse models, which are based on a triple alanine to proline mutation and a C-terminal truncation of αSyn, but do not overexpress the mutant protein when compared to the endogenous mouse protein. We knocked hαSyn TP or hαSynΔ119 (h stands for "human") into the murine αSyn locus. hαSynTP is a structure-based mutant with triple alanine to proline substitutions that favors oligomers, is neurotoxic and evokes PD-like symptoms in Drosophila melanogaster. hαSynΔ119 lacks 21 amino acids at the C-terminus, favors fibrillary aggregates and occurs in PD. Knocking-in of hαSyn TP or hαSynΔ119 into the murine αSyn locus places the mutant protein under the control of the endogenous regulatory elements while simultaneously disrupting the mαSyn gene. Mass spectrometry revealed that hαSyn TP and hαSynΔ119 mice produced 12 and 10 times less mutant protein, compared to mαSyn in wild type mice. We show phenotypes in 1 and 1.5 years old hαSyn TP and hαSynΔ119 mice, despite the lower levels of hαSynTP and hαSynΔ119 expression. Direct comparison of the two mouse models revealed many commonalities but also aspects unique to each model. Commonalities included strong immunoactive state, impaired olfaction and motor coordination deficits. Neither model showed DAergic neuronal loss. Impaired climbing abilities at 1 year of age and a deviant gait pattern at 1.5 years old were specific for hαSynΔ119 mice, while a compulsive behavior was exclusively detected in hαSyn TP mice starting at 1 year of age. We conclude that even at very moderate levels of expression the two αSyn variants evoke measurable and progressive deficiencies in mutant mice. The two transgenic mouse models can thus be suitable to study αSyn-variant-based pathology in vivo and test new therapeutic approaches.
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Affiliation(s)
- Ana Martinez Hernandez
- Genes and Behavior Department, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany
| | - Ivan Silbern
- Institute of Clinical Chemistry, University Medical Center Göttingen, Göttingen, Germany.,Bioanalytical Mass Spectrometry Group, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany
| | - Insa Geffers
- Genes and Behavior Department, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany
| | - Lars Tatenhorst
- Department of Neurology, University Medical Center Göttingen, University of Göttingen, Göttingen, Germany.,Cluster of Excellence Nanoscale Microscopy and Molecular Physiology of the Brain, Göttingen, Germany.,Center for Biostructural Imaging of Neurodegeneration, University Medical Center Göttingen, Göttingen, Germany
| | - Stefan Becker
- NMR-Based Structural Biology Department, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany
| | - Henning Urlaub
- Institute of Clinical Chemistry, University Medical Center Göttingen, Göttingen, Germany.,Bioanalytical Mass Spectrometry Group, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany
| | - Markus Zweckstetter
- Department of Neurology, University Medical Center Göttingen, University of Göttingen, Göttingen, Germany.,NMR-Based Structural Biology Department, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany.,German Center for Neurodegenerative Diseases, DZNE, Göttingen, Germany
| | - Christian Griesinger
- Cluster of Excellence Nanoscale Microscopy and Molecular Physiology of the Brain, Göttingen, Germany.,NMR-Based Structural Biology Department, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany.,Cluster of Excellence "Multiscale Bioimaging: From Molecular Machines to Networks of Excitable Cells" (MBExC), University of Göttingen, Göttingen, Germany
| | - Gregor Eichele
- Genes and Behavior Department, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany
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84
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Beach TG, Adler CH, Sue LI, Shill HA, Driver-Dunckley E, Mehta SH, Intorcia AJ, Glass MJ, Walker JE, Arce R, Nelson CM, Serrano GE. Vagus Nerve and Stomach Synucleinopathy in Parkinson's Disease, Incidental Lewy Body Disease, and Normal Elderly Subjects: Evidence Against the "Body-First" Hypothesis. JOURNAL OF PARKINSONS DISEASE 2021; 11:1833-1843. [PMID: 34151862 PMCID: PMC10082635 DOI: 10.3233/jpd-212733] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
BACKGROUND Braak and others have proposed that Lewy-type α-synucleinopathy in Parkinson's disease (PD) may arise from an exogenous pathogen that passes across the gastric mucosa and then is retrogradely transported up the vagus nerve to the medulla. OBJECTIVE We tested this hypothesis by immunohistochemically staining, with a method specific for p-serine 129 α-synuclein (pSyn), stomach and vagus nerve tissue from an autopsy series of 111 normal elderly subjects, 33 with incidental Lewy body disease (ILBD) and 53 with PD. METHODS Vagus nerve samples were taken adjacent to the carotid artery in the neck. Stomach samples were taken from the gastric body, midway along the greater curvature. Formalin-fixed paraffin-embedded sections were immunohistochemically stained for pSyn, shown to be highly specific and sensitive for α-synuclein pathology. RESULTS Median disease duration for the PD group was 13 years. In the vagus nerve none of the 111 normal subjects had pSyn in the vagus, while 12/26 ILBD (46%) and 32/36 PD (89%) subjects were pSyn-positive. In the stomach none of the 102 normal subjects had pSyn while 5/30 (17%) ILBD and 42/52 (81%) of PD subjects were pSyn-positive. CONCLUSION As there was no pSyn in the vagus nerve or stomach of subjects without brain pSyn, these results support initiation of pSyn in the brain. The presence of pSyn in the vagus nerve and stomach of a subset of ILBD cases indicates that synucleinopathy within the peripheral nervous system may occur, within a subset of individuals, at preclinical stages of Lewy body disease.
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Affiliation(s)
| | - Charles H Adler
- Mayo Clinic College of Medicine, Mayo Clinic Arizona, Scottsdale, AZ, USA
| | - Lucia I Sue
- Banner Sun Health Research Institute, Sun City, AZ, USA
| | | | | | - Shyamal H Mehta
- Mayo Clinic College of Medicine, Mayo Clinic Arizona, Scottsdale, AZ, USA
| | | | | | | | - Richard Arce
- Banner Sun Health Research Institute, Sun City, AZ, USA
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85
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Bluhm A, Schrempel S, von Hörsten S, Schulze A, Roßner S. Proteolytic α-Synuclein Cleavage in Health and Disease. Int J Mol Sci 2021; 22:5450. [PMID: 34064208 PMCID: PMC8196865 DOI: 10.3390/ijms22115450] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 05/17/2021] [Accepted: 05/17/2021] [Indexed: 12/13/2022] Open
Abstract
In Parkinson's disease, aggregates of α-synuclein within Lewy bodies and Lewy neurites represent neuropathological hallmarks. However, the cellular and molecular mechanisms triggering oligomeric and fibrillary α-synuclein aggregation are not fully understood. Recent evidence indicates that oxidative stress induced by metal ions and post-translational modifications such as phosphorylation, ubiquitination, nitration, glycation, and SUMOylation affect α-synuclein conformation along with its aggregation propensity and neurotoxic profiles. In addition, proteolytic cleavage of α-synuclein by specific proteases results in the formation of a broad spectrum of fragments with consecutively altered and not fully understood physiological and/or pathological properties. In the present review, we summarize the current knowledge on proteolytical α-synuclein cleavage by neurosin, calpain-1, cathepsin D, and matrix metalloproteinase-3 in health and disease. We also shed light on the contribution of the same enzymes to proteolytical processing of pathogenic proteins in Alzheimer's disease and report potential cross-disease mechanisms of pathogenic protein aggregation.
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Affiliation(s)
- Alexandra Bluhm
- Flechsig Institute for Brain Research, University of Leipzig, 04103 Leipzig, Germany; (A.B.); (S.S.)
| | - Sarah Schrempel
- Flechsig Institute for Brain Research, University of Leipzig, 04103 Leipzig, Germany; (A.B.); (S.S.)
| | - Stephan von Hörsten
- Department for Experimental Therapy, University Clinics Erlangen and Preclinical Experimental Center, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91054 Erlangen, Germany;
| | - Anja Schulze
- Department of Molecular Drug Design and Target Validation, Fraunhofer Institute for Cell Therapy and Immunology, 06120 Halle/Saale, Germany;
| | - Steffen Roßner
- Flechsig Institute for Brain Research, University of Leipzig, 04103 Leipzig, Germany; (A.B.); (S.S.)
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86
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Chhangani D, Martín-Peña A, Rincon-Limas DE. Molecular, functional, and pathological aspects of TDP-43 fragmentation. iScience 2021; 24:102459. [PMID: 34013172 PMCID: PMC8113996 DOI: 10.1016/j.isci.2021.102459] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Transactive response DNA binding protein 43 (TDP-43) is a DNA/RNA binding protein involved in transcriptional regulation and RNA processing. It is linked to sporadic and familial amyotrophic lateral sclerosis and frontotemporal lobar degeneration. TDP-43 is predominantly nuclear, but it translocates to the cytoplasm under pathological conditions. Cytoplasmic accumulation, phosphorylation, ubiquitination and truncation of TDP-43 are the main hallmarks of TDP-43 proteinopathies. Among these processes, the pathways leading to TDP-43 fragmentation remain poorly understood. We review here the molecular and biochemical properties of several TDP-43 fragments, the mechanisms and factors mediating their production, and their potential role in disease progression. We also address the presence of TDP-43 C-terminal fragments in several neurological disorders, including Alzheimer's disease, and highlight their respective implications. Finally, we discuss features of animal models expressing TDP-43 fragments as well as recent therapeutic strategies to approach TDP-43 truncation.
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Affiliation(s)
- Deepak Chhangani
- Department of Neurology, McKnight Brain Institute, and Norman Fixel Institute for Neurological Diseases, University of Florida, Gainesville, FL 32611, USA
| | - Alfonso Martín-Peña
- Department of Neurology, McKnight Brain Institute, and Norman Fixel Institute for Neurological Diseases, University of Florida, Gainesville, FL 32611, USA
| | - Diego E Rincon-Limas
- Department of Neurology, McKnight Brain Institute, and Norman Fixel Institute for Neurological Diseases, University of Florida, Gainesville, FL 32611, USA.,Department of Neuroscience, Center for Translational Research in Neurodegenerative Disease, University of Florida, Gainesville, FL 32611, USA.,Genetics Institute, University of Florida, Gainesville, FL 32611, USA
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87
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Hass EW, Sorrentino ZA, Lloyd GM, McFarland NR, Prokop S, Giasson BI. Robust α-synuclein pathology in select brainstem neuronal populations is a potential instigator of multiple system atrophy. Acta Neuropathol Commun 2021; 9:80. [PMID: 33941284 PMCID: PMC8091528 DOI: 10.1186/s40478-021-01173-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Accepted: 03/28/2021] [Indexed: 12/23/2022] Open
Abstract
Multiple system atrophy (MSA) is an insidious middle age-onset neurodegenerative disease that clinically presents with variable degrees of parkinsonism and cerebellar ataxia. The pathological hallmark of MSA is the progressive accumulation of glial cytoplasmic inclusions (GCIs) in oligodendrocytes that are comprised of α-synuclein (αSyn) aberrantly polymerized into fibrils. Experimentally, MSA brain samples display a high level of seeding activity to induce further αSyn aggregation by a prion-like conformational mechanism. Paradoxically, αSyn is predominantly a neuronal brain protein, with only marginal levels expressed in normal or diseased oligodendrocytes, and αSyn inclusions in other neurodegenerative diseases, including Parkinson's disease and Dementia with Lewy bodies, are primarily found in neurons. Although GCIs are the hallmark of MSA, using a series of new monoclonal antibodies targeting the carboxy-terminal region of αSyn, we demonstrate that neuronal αSyn pathology in MSA patient brains is remarkably abundant in the pontine nuclei and medullary inferior olivary nucleus. This neuronal αSyn pathology has distinct histological properties compared to GCIs, which allows it to remain concealed to many routine detection methods associated with altered biochemical properties of the carboxy-terminal domain of αSyn. We propose that these previously underappreciated sources of aberrant αSyn could serve as a pool of αSyn prion seeds that can initiate and continue to drive the pathogenesis of MSA.
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Affiliation(s)
- Ethan W Hass
- Department of Neuroscience, College of Medicine, University of Florida, BMS J483/CTRND, 1275 Center Drive, Gainesville, FL, 32610, USA
- Center for Translational Research in Neurodegenerative Disease, College of Medicine, University of Florida, Gainesville, FL, 32610, USA
| | - Zachary A Sorrentino
- Department of Neuroscience, College of Medicine, University of Florida, BMS J483/CTRND, 1275 Center Drive, Gainesville, FL, 32610, USA
- Center for Translational Research in Neurodegenerative Disease, College of Medicine, University of Florida, Gainesville, FL, 32610, USA
| | - Grace M Lloyd
- Department of Neuroscience, College of Medicine, University of Florida, BMS J483/CTRND, 1275 Center Drive, Gainesville, FL, 32610, USA
- Center for Translational Research in Neurodegenerative Disease, College of Medicine, University of Florida, Gainesville, FL, 32610, USA
| | - Nikolaus R McFarland
- Center for Translational Research in Neurodegenerative Disease, College of Medicine, University of Florida, Gainesville, FL, 32610, USA
- McKnight Brain Institute, College of Medicine, University of Florida, Gainesville, FL, 32610, USA
- Department of Neurology, College of Medicine, University of Florida, Gainesville, FL, 32610, USA
| | - Stefan Prokop
- Center for Translational Research in Neurodegenerative Disease, College of Medicine, University of Florida, Gainesville, FL, 32610, USA
- McKnight Brain Institute, College of Medicine, University of Florida, Gainesville, FL, 32610, USA
- Department of Pathology, College of Medicine, University of Florida, Gainesville, FL, 32610, USA
| | - Benoit I Giasson
- Department of Neuroscience, College of Medicine, University of Florida, BMS J483/CTRND, 1275 Center Drive, Gainesville, FL, 32610, USA.
- Center for Translational Research in Neurodegenerative Disease, College of Medicine, University of Florida, Gainesville, FL, 32610, USA.
- McKnight Brain Institute, College of Medicine, University of Florida, Gainesville, FL, 32610, USA.
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88
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Fukui N, Yamamoto H, Miyabe M, Aoyama Y, Hongo K, Mizobata T, Kawahata I, Yabuki Y, Shinoda Y, Fukunaga K, Kawata Y. An α-synuclein decoy peptide prevents cytotoxic α-synuclein aggregation caused by fatty acid binding protein 3. J Biol Chem 2021; 296:100663. [PMID: 33862084 PMCID: PMC8131325 DOI: 10.1016/j.jbc.2021.100663] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2020] [Revised: 04/07/2021] [Accepted: 04/12/2021] [Indexed: 12/23/2022] Open
Abstract
α-synuclein (αSyn) is a protein known to form intracellular aggregates during the manifestation of Parkinson’s disease. Previously, it was shown that αSyn aggregation was strongly suppressed in the midbrain region of mice that did not possess the gene encoding the lipid transport protein fatty acid binding protein 3 (FABP3). An interaction between these two proteins was detected in vitro, suggesting that FABP3 may play a role in the aggregation and deposition of αSyn in neurons. To characterize the molecular mechanisms that underlie the interactions between FABP3 and αSyn that modulate the cellular accumulation of the latter, in this report, we used in vitro fluorescence assays combined with fluorescence microscopy, transmission electron microscopy, and quartz crystal microbalance assays to characterize in detail the process and consequences of FABP3–αSyn interaction. We demonstrated that binding of FABP3 to αSyn results in changes in the aggregation mechanism of the latter; specifically, a suppression of fibrillar forms of αSyn and also the production of aggregates with an enhanced cytotoxicity toward mice neuro2A cells. Because this interaction involved the C-terminal sequence region of αSyn, we tested a peptide derived from this region of αSyn (αSynP130-140) as a decoy to prevent the FABP3–αSyn interaction. We observed that the peptide competitively inhibited binding of αSyn to FABP3 in vitro and in cultured cells. We propose that administration of αSynP130-140 might be used to prevent the accumulation of toxic FABP3-αSyn oligomers in cells, thereby preventing the progression of Parkinson’s disease.
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Affiliation(s)
- Naoya Fukui
- Department of Chemistry and Biotechnology, Faculty of Engineering/Graduate School of Engineering, Tottori University, Tottori, Japan
| | - Hanae Yamamoto
- Department of Chemistry and Biotechnology, Faculty of Engineering/Graduate School of Engineering, Tottori University, Tottori, Japan
| | - Moe Miyabe
- Department of Chemistry and Biotechnology, Faculty of Engineering/Graduate School of Engineering, Tottori University, Tottori, Japan
| | - Yuki Aoyama
- Department of Chemistry and Biotechnology, Faculty of Engineering/Graduate School of Engineering, Tottori University, Tottori, Japan
| | - Kunihiro Hongo
- Department of Chemistry and Biotechnology, Faculty of Engineering/Graduate School of Engineering, Tottori University, Tottori, Japan; Department of Biomedical Science, Institute of Regenerative Medicine and Biofunction, Graduate School of Medical Science, Tottori University, Tottori, Japan; Center for Research on Green Sustainable Chemistry, Tottori University, Tottori, Japan
| | - Tomohiro Mizobata
- Department of Chemistry and Biotechnology, Faculty of Engineering/Graduate School of Engineering, Tottori University, Tottori, Japan; Department of Biomedical Science, Institute of Regenerative Medicine and Biofunction, Graduate School of Medical Science, Tottori University, Tottori, Japan; Center for Research on Green Sustainable Chemistry, Tottori University, Tottori, Japan
| | - Ichiro Kawahata
- Department of Pharmacology, Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Japan
| | - Yasushi Yabuki
- Department of Pharmacology, Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Japan
| | - Yasuharu Shinoda
- Department of Pharmacology, Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Japan
| | - Kohji Fukunaga
- Department of Pharmacology, Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Japan
| | - Yasushi Kawata
- Department of Chemistry and Biotechnology, Faculty of Engineering/Graduate School of Engineering, Tottori University, Tottori, Japan; Department of Biomedical Science, Institute of Regenerative Medicine and Biofunction, Graduate School of Medical Science, Tottori University, Tottori, Japan; Center for Research on Green Sustainable Chemistry, Tottori University, Tottori, Japan.
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89
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He S, Wang F, Yung KKL, Zhang S, Qu S. Effects of α-Synuclein-Associated Post-Translational Modifications in Parkinson's Disease. ACS Chem Neurosci 2021; 12:1061-1071. [PMID: 33769791 DOI: 10.1021/acschemneuro.1c00028] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
α-Synuclein (α-syn), a small highly conserved presynaptic protein containing 140 amino acids, is thought to be the main pathological hallmark in related neurodegenerative disorders. Although the normal function of α-syn is closely involved in the regulation of vesicular neurotransmission in these diseases, the underlying mechanisms of post-translational modifications (PTMs) of α-syn in the pathogenesis of Parkinson's disease (PD) have not been fully characterized. The pathological accumulation of misfolded α-syn has a critical role in PD pathogenesis. Recent studies of factors contributing to α-syn-associated aggregation and misfolding have expanded our understanding of the PD disease process. In this Review, we summarize the structure and physiological function of α-syn, and we further highlight the major PTMs (namely phosphorylation, ubiquitination, nitration, acetylation, truncation, SUMOylation, and O-GlcNAcylation) of α-syn and the effects of these modifications on α-syn aggregation, which may elucidate mechanisms for PD pathogenesis and lay a theoretical foundation for clinical treatment of PD.
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Affiliation(s)
- Songzhe He
- Department of Neurology, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong 510515, China
- Guangdong-Hong Kong-Macao Greater Bay Area Center for Brain Science and Brain-Inspired Intelligence, Guangzhou, Guangdong 510515, China
- Key Laboratory of Mental Health of the Ministry of Education, Southern Medical University, Guangzhou, Guangdong 510515, China
| | - Fushun Wang
- Institute of Brain and Psychological Science, Sichuan Normal University, Chengdu, Sichuan 610066, China
- Department of Neurosurgery, University of Rochester Medical Center, New York, 14643, United States
| | - Ken Kin Lam Yung
- Department of Biology, Faculty of Science, Hong Kong Baptist University, Hong Kong, 999077, China
| | - Shiqing Zhang
- Department of Biology, Faculty of Science, Hong Kong Baptist University, Hong Kong, 999077, China
| | - Shaogang Qu
- Department of Neurology, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong 510515, China
- Guangdong-Hong Kong-Macao Greater Bay Area Center for Brain Science and Brain-Inspired Intelligence, Guangzhou, Guangdong 510515, China
- Key Laboratory of Mental Health of the Ministry of Education, Southern Medical University, Guangzhou, Guangdong 510515, China
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90
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Lövestam S, Schweighauser M, Matsubara T, Murayama S, Tomita T, Ando T, Hasegawa K, Yoshida M, Tarutani A, Hasegawa M, Goedert M, Scheres SHW. Seeded assembly in vitro does not replicate the structures of α-synuclein filaments from multiple system atrophy. FEBS Open Bio 2021; 11:999-1013. [PMID: 33548114 PMCID: PMC8016116 DOI: 10.1002/2211-5463.13110] [Citation(s) in RCA: 75] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Accepted: 02/04/2021] [Indexed: 11/26/2022] Open
Abstract
The propagation of conformational strains by templated seeding is central to the prion concept. Seeded assembly of α‐synuclein into filaments is believed to underlie the prion‐like spreading of protein inclusions in a number of human neurodegenerative diseases, including Parkinson's disease, dementia with Lewy bodies (DLB) and multiple system atrophy (MSA). We previously determined the atomic structures of α‐synuclein filaments from the putamen of five individuals with MSA. Here, we used filament preparations from three of these brains for the in vitro seeded assembly of recombinant human α‐synuclein. We find that the structures of the seeded assemblies differ from those of the seeds, suggesting that additional, as yet unknown, factors play a role in the propagation of the seeds. Identification of these factors will be essential for understanding the prion‐like spreading of α‐synuclein proteinopathies.
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Affiliation(s)
| | | | - Tomoyasu Matsubara
- Department of Neuropathology, Tokyo Metropolitan Institute of Gerontology, Japan
| | - Shigeo Murayama
- Department of Neuropathology, Tokyo Metropolitan Institute of Gerontology, Japan
| | - Taisuke Tomita
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, Japan
| | - Takashi Ando
- Department of Neurology, Nagoya University Graduate School of Medicine, Japan
| | | | - Mari Yoshida
- Institute for Medical Science of Aging, Aichi Medical University, Nagakute, Japan
| | - Airi Tarutani
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, Japan.,Department of Brain and Neurosciences, Tokyo Metropolitan Institute of Medical Science, Japan
| | - Masato Hasegawa
- Department of Brain and Neurosciences, Tokyo Metropolitan Institute of Medical Science, Japan
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91
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Synergistic Effects of Milk-Derived Exosomes and Galactose on α-Synuclein Pathology in Parkinson's Disease and Type 2 Diabetes Mellitus. Int J Mol Sci 2021; 22:ijms22031059. [PMID: 33494388 PMCID: PMC7865729 DOI: 10.3390/ijms22031059] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Revised: 01/14/2021] [Accepted: 01/19/2021] [Indexed: 12/11/2022] Open
Abstract
Epidemiological studies associate milk consumption with an increased risk of Parkinson's disease (PD) and type 2 diabetes mellitus (T2D). PD is an α-synucleinopathy associated with mitochondrial dysfunction, oxidative stress, deficient lysosomal clearance of α-synuclein (α-syn) and aggregation of misfolded α-syn. In T2D, α-syn promotes co-aggregation with islet amyloid polypeptide in pancreatic β-cells. Prion-like vagal nerve-mediated propagation of exosomal α-syn from the gut to the brain and pancreatic islets apparently link both pathologies. Exosomes are critical transmitters of α-syn from cell to cell especially under conditions of compromised autophagy. This review provides translational evidence that milk exosomes (MEX) disturb α-syn homeostasis. MEX are taken up by intestinal epithelial cells and accumulate in the brain after oral administration to mice. The potential uptake of MEX miRNA-148a and miRNA-21 by enteroendocrine cells in the gut, dopaminergic neurons in substantia nigra and pancreatic β-cells may enhance miRNA-148a/DNMT1-dependent overexpression of α-syn and impair miRNA-148a/PPARGC1A- and miRNA-21/LAMP2A-dependent autophagy driving both diseases. MiRNA-148a- and galactose-induced mitochondrial oxidative stress activate c-Abl-mediated aggregation of α-syn which is exported by exosome release. Via the vagal nerve and/or systemic exosomes, toxic α-syn may spread to dopaminergic neurons and pancreatic β-cells linking the pathogenesis of PD and T2D.
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92
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Giannoccaro MP, Donadio V, Giannini G, Devigili G, Rizzo G, Incensi A, Cason E, Calandra-Buonaura G, Eleopra R, Cortelli P, Liguori R. Comparison of 123I-MIBG scintigraphy and phosphorylated α-synuclein skin deposits in synucleinopathies. Parkinsonism Relat Disord 2020; 81:48-53. [PMID: 33049589 DOI: 10.1016/j.parkreldis.2020.10.016] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/27/2020] [Revised: 09/30/2020] [Accepted: 10/07/2020] [Indexed: 11/29/2022]
Abstract
INTRODUCTION Cardiac [123I]metaiodobenzylguanidine scintigraphy (123I-MIBG) is considered a useful test in differentiating multiple system atrophy (MSA) and Lewy body disorders (LBD), including idiopathic Parkinson's disease (IPD), dementia with Lewy bodies (DLB) and pure autonomic failure (PAF). The detection of skin nerve phosphorylated α-synuclein (p-α-syn) deposits could be an alternative marker in vivo. We sought to compare 123I-MIBG scintigraphy and skin biopsy findings in α-synucleinopathies. METHODS We studied 54 patients (7 DLB, 21 IPD, 13 PAF, 13 MSA) who underwent 123I-MIBG scintigraphy and skin biopsy to evaluate cardiac innervation and skin p-α-syn deposition, respectively. RESULTS Cardiac denervation was observed in 90.5% IPD, 100% DLB and PAF and in none of the MSA patients (P < 0.0001) whereas p-α-syn deposits were detected in all DLB and PAF, in 95.2% of IPD and 69.2% of MSA patients (P = 0.02). However, the analysis of skin structures disclosed a different distribution of the deposits in somatic subepidermal plexus and autonomic fibers among groups, showing that p-α-syn deposits rarely affected the autonomic fibers in MSA as opposed to LBD. Studying the p-α-syn deposition in autonomic nerves, concordance among I123-MIBG scintigraphy and skin biopsy results was observed in 100% of DLB and PAF, 95.2% IPD and 92.3% MSA patients. I123-MIBG scintigraphy and autonomic p-α-syn deposits analysis both showed a sensitivity of 97.5% and a specificity of 100% and 92.3%, respectively, in distinguishing LBD and MSA. CONCLUSION Skin biopsy and 123-MIBG scintigraphy can be considered alternative tests for the differential diagnosis of IPD, PAF and DLB versus MSA.
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Affiliation(s)
- Maria Pia Giannoccaro
- IRCCS Istituto delle Scienze Neurologiche di Bologna, Bologna, Italy; Dipartimento di Scienze Biomediche e Neuromotorie, Università di Bologna, Bologna, Italy.
| | - Vincenzo Donadio
- IRCCS Istituto delle Scienze Neurologiche di Bologna, Bologna, Italy
| | - Giulia Giannini
- IRCCS Istituto delle Scienze Neurologiche di Bologna, Bologna, Italy; Dipartimento di Scienze Biomediche e Neuromotorie, Università di Bologna, Bologna, Italy
| | - Grazia Devigili
- Neurological Unit 1, Fondazione I.R.C.C.S, Istituto Neurologico Carlo Besta, 20133, Milan, Italy
| | - Giovanni Rizzo
- IRCCS Istituto delle Scienze Neurologiche di Bologna, Bologna, Italy; Dipartimento di Scienze Biomediche e Neuromotorie, Università di Bologna, Bologna, Italy
| | - Alex Incensi
- IRCCS Istituto delle Scienze Neurologiche di Bologna, Bologna, Italy
| | - Ernesto Cason
- U.O. di Medicina Nucleare, Azienda AUSL Bologna, Ospedale Maggiore, Italy
| | - Giovanna Calandra-Buonaura
- IRCCS Istituto delle Scienze Neurologiche di Bologna, Bologna, Italy; Dipartimento di Scienze Biomediche e Neuromotorie, Università di Bologna, Bologna, Italy
| | - Roberto Eleopra
- Neurological Unit 1, Fondazione I.R.C.C.S, Istituto Neurologico Carlo Besta, 20133, Milan, Italy
| | - Pietro Cortelli
- IRCCS Istituto delle Scienze Neurologiche di Bologna, Bologna, Italy; Dipartimento di Scienze Biomediche e Neuromotorie, Università di Bologna, Bologna, Italy
| | - Rocco Liguori
- IRCCS Istituto delle Scienze Neurologiche di Bologna, Bologna, Italy; Dipartimento di Scienze Biomediche e Neuromotorie, Università di Bologna, Bologna, Italy
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P2X7 Receptors Amplify CNS Damage in Neurodegenerative Diseases. Int J Mol Sci 2020; 21:ijms21175996. [PMID: 32825423 PMCID: PMC7504621 DOI: 10.3390/ijms21175996] [Citation(s) in RCA: 66] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Revised: 08/07/2020] [Accepted: 08/17/2020] [Indexed: 12/11/2022] Open
Abstract
ATP is a (co)transmitter and signaling molecule in the CNS. It acts at a multitude of ligand-gated cationic channels termed P2X to induce rapid depolarization of the cell membrane. Within this receptor-channel family, the P2X7 receptor (R) allows the transmembrane fluxes of Na+, Ca2+, and K+, but also allows the slow permeation of larger organic molecules. This is supposed to cause necrosis by excessive Ca2+ influx, as well as depletion of intracellular ions and metabolites. Cell death may also occur by apoptosis due to the activation of the caspase enzymatic cascade. Because P2X7Rs are localized in the CNS preferentially on microglia, but also at a lower density on neuroglia (astrocytes, oligodendrocytes) the stimulation of this receptor leads to the release of neurodegeneration-inducing bioactive molecules such as pro-inflammatory cytokines, chemokines, proteases, reactive oxygen and nitrogen molecules, and the excitotoxic glutamate/ATP. Various neurodegenerative reactions of the brain/spinal cord following acute harmful events (mechanical CNS damage, ischemia, status epilepticus) or chronic neurodegenerative diseases (neuropathic pain, Alzheimer’s disease, Parkinson’s disease, multiple sclerosis, amyotrophic lateral sclerosis) lead to a massive release of ATP via the leaky plasma membrane of neural tissue. This causes cellular damage superimposed on the original consequences of neurodegeneration. Hence, blood-brain-barrier permeable pharmacological antagonists of P2X7Rs with excellent bioavailability are possible therapeutic agents for these diseases. The aim of this review article is to summarize our present state of knowledge on the involvement of P2X7R-mediated events in neurodegenerative illnesses endangering especially the life quality and duration of the aged human population.
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