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Flønes IH, Tzoulis C. Mitochondrial Respiratory Chain Dysfunction—A Hallmark Pathology of Idiopathic Parkinson’s Disease? Front Cell Dev Biol 2022; 10:874596. [PMID: 35433702 PMCID: PMC9010539 DOI: 10.3389/fcell.2022.874596] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2022] [Accepted: 03/10/2022] [Indexed: 12/21/2022] Open
Abstract
Parkinson’s disease (PD) is the most common age-dependent neurodegenerative synucleinopathy. Loss of dopaminergic neurons of the substantia nigra pars compacta, together with region- and cell-specific aggregations of α-synuclein are considered main pathological hallmarks of PD, but its etiopathogenesis remains largely unknown. Mitochondrial dysfunction, in particular quantitative and/or functional deficiencies of the mitochondrial respiratory chain (MRC), has been associated with the disease. However, after decades of research in this field, the pervasiveness and anatomical extent of MRC dysfunction in PD remain largely unknown. Moreover, it is not known whether the observed MRC defects are pathogenic, compensatory responses, or secondary epiphenomena. In this perspective, we give an overview of current evidence for MRC dysfunction in PD, highlight pertinent knowledge gaps, and propose potential strategies for future research.
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Affiliation(s)
- Irene H. Flønes
- Neuro-SysMed, Department of Neurology, Haukeland University Hospital, Bergen, Norway
- K.G Jebsen Center for Translational Research in Parkinson’s Disease, University of Bergen, Bergen, Norway
- Department of Clinical Medicine, University of Bergen, Bergen, Norway
| | - Charalampos Tzoulis
- Neuro-SysMed, Department of Neurology, Haukeland University Hospital, Bergen, Norway
- K.G Jebsen Center for Translational Research in Parkinson’s Disease, University of Bergen, Bergen, Norway
- Department of Clinical Medicine, University of Bergen, Bergen, Norway
- *Correspondence: Charalampos Tzoulis,
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102
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Choong CJ, Mochizuki H. Neuropathology of α-synuclein in Parkinson's disease. Neuropathology 2022; 42:93-103. [PMID: 35362115 DOI: 10.1111/neup.12812] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2022] [Revised: 02/24/2022] [Accepted: 02/28/2022] [Indexed: 01/21/2023]
Abstract
Parkinson's disease (PD) is a neurodegenerative disorder characterized by progressive movement disability accompanied by non-motor symptoms. The neuropathology hallmark of PD is the loss of dopaminergic neurons predominantly in the substantia nigra pars compacta and the presence of intracellular inclusions termed Lewy bodies (LBs), which are mainly composed of α-synuclein (αSyn). Detailed staging based on the distribution and progression pattern of αSyn pathology in the postmortem brains of PD patients revealed correlation with the clinical phenotypes but not invariably. Cumulative evidence from cell and animal studies has implied that αSyn propagation contributes to the anatomical spread of αSyn pathology in the brain. Here, we recount the studies over the past two centuries on the anatomopathological foundations of PD documented. We also review studies on the structural analysis of αSyn and LBs, Braak staging of αSyn pathology, the cell-to-cell propagation of αSyn as well as αSyn fibril polymorphisms, which underlie the phenotypic differences in synucleinopathies.
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Affiliation(s)
- Chi-Jing Choong
- Department of Neurology, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Hideki Mochizuki
- Department of Neurology, Osaka University Graduate School of Medicine, Osaka, Japan
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103
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Initiation and progression of α-synuclein pathology in Parkinson’s disease. Cell Mol Life Sci 2022; 79:210. [PMID: 35347432 PMCID: PMC8960654 DOI: 10.1007/s00018-022-04240-2] [Citation(s) in RCA: 30] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2022] [Revised: 03/08/2022] [Accepted: 03/09/2022] [Indexed: 12/21/2022]
Abstract
α-Synuclein aggregation is a critical molecular process that underpins the pathogenesis of Parkinson’s disease. Aggregates may originate at synaptic terminals as a consequence of aberrant interactions between α-synuclein and lipids or evasion of proteostatic defences. The nature of these interactions is likely to influence the emergence of conformers or strains that in turn could explain the clinical heterogeneity of Parkinson’s disease and related α-synucleinopathies. For neurodegeneration to occur, α-synuclein assemblies need to exhibit seeding competency, i.e. ability to template further aggregation, and toxicity which is at least partly mediated by interference with synaptic vesicle or organelle homeostasis. Given the dynamic and reversible conformational plasticity of α-synuclein, it is possible that seeding competency and cellular toxicity are mediated by assemblies of different structure or size along this continuum. It is currently unknown which α-synuclein assemblies are the most relevant to the human condition but recent advances in the cryo-electron microscopic characterisation of brain-derived fibrils and their assessment in stem cell derived and animal models are likely to facilitate the development of precision therapies or biomarkers. This review summarises the main principles of α-synuclein aggregate initiation and propagation in model systems, and their relevance to clinical translation.
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104
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Lopes DM, Llewellyn SK, Harrison IF. Propagation of tau and α-synuclein in the brain: therapeutic potential of the glymphatic system. Transl Neurodegener 2022; 11:19. [PMID: 35314000 PMCID: PMC8935752 DOI: 10.1186/s40035-022-00293-2] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Accepted: 03/03/2022] [Indexed: 12/12/2022] Open
Abstract
Many neurodegenerative diseases, including Alzheimer’s disease and Parkinson’s disease, are characterised by the accumulation of misfolded protein deposits in the brain, leading to a progressive destabilisation of the neuronal network and neuronal death. Among the proteins that can abnormally accumulate are tau and α-synuclein, which can propagate in a prion-like manner and which upon aggregation, represent the most common intracellular proteinaceous lesions associated with neurodegeneration. For years it was thought that these intracellular proteins and their accumulation had no immediate relationship with extracellular homeostasis pathways such as the glymphatic clearance system; however, mounting evidence has now suggested that this is not the case. The involvement of the glymphatic system in neurodegenerative disease is yet to be fully defined; however, it is becoming increasingly clear that this pathway contributes to parenchymal solute clearance. Importantly, recent data show that proteins prone to intracellular accumulation are subject to glymphatic clearance, suggesting that this system plays a key role in many neurological disorders. In this review, we provide a background on the biology of tau and α-synuclein and discuss the latest findings on the cell-to-cell propagation mechanisms of these proteins. Importantly, we discuss recent data demonstrating that manipulation of the glymphatic system may have the potential to alleviate and reduce pathogenic accumulation of propagation-prone intracellular cytotoxic proteins. Furthermore, we will allude to the latest potential therapeutic opportunities targeting the glymphatic system that might have an impact as disease modifiers in neurodegenerative diseases.
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105
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Effects of oligomer toxicity, fibril toxicity and fibril spreading in synucleinopathies. Cell Mol Life Sci 2022; 79:174. [PMID: 35244787 PMCID: PMC8897347 DOI: 10.1007/s00018-022-04166-9] [Citation(s) in RCA: 50] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Revised: 01/17/2022] [Accepted: 01/22/2022] [Indexed: 12/18/2022]
Abstract
Protein misfolding is a general hallmark of protein deposition diseases, such as Alzheimer’s disease or Parkinson’s disease, in which different types of aggregated species (oligomers, protofibrils and fibrils) are generated by the cells. Despite widespread interest, the relationship between oligomers and fibrils in the aggregation process and spreading remains elusive. A large variety of experimental evidences supported the idea that soluble oligomeric species of different proteins might be more toxic than the larger fibrillar forms. Furthermore, the lack of correlation between the presence of the typical pathological inclusions and disease sustained this debate. However, recent data show that the β-sheet core of the α-Synuclein (αSyn) fibrils is unable to establish persistent interactions with the lipid bilayers, but they can release oligomeric species responsible for an immediate dysfunction of the recipient neurons. Reversibly, such oligomeric species could also contribute to pathogenesis via neuron-to-neuron spreading by their direct cell-to-cell transfer or by generating new fibrils, following their neuronal uptake. In this Review, we discuss the various mechanisms of cellular dysfunction caused by αSyn, including oligomer toxicity, fibril toxicity and fibril spreading.
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106
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Glycation modulates alpha-synuclein fibrillization kinetics: a sweet spot for inhibition. J Biol Chem 2022; 298:101848. [PMID: 35314196 PMCID: PMC9034100 DOI: 10.1016/j.jbc.2022.101848] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Revised: 03/05/2022] [Accepted: 03/07/2022] [Indexed: 01/24/2023] Open
Abstract
Glycation is a nonenzymatic posttranslational modification (PTM) known to be increased in the brains of hyperglycemic patients. Alpha-synuclein (αSN), a central player in the etiology of Parkinson’s disease, can be glycated at lysine residues, thereby reducing αSN fibril formation in vitro and modulating αSN aggregation in cells. However, the molecular basis for these effects is unclear. To elucidate this, we investigated the aggregation of αSN modified by eight glycating agents, namely the dicarbonyl compound methylglyoxal (MGO) and the sugars ribose, fructose, mannose, glucose, galactose, sucrose, and lactose. We found that MGO and ribose modify αSN to the greatest extent, and these glycation products are the most efficient inhibitors of fibril formation. We show glycation primarily inhibits elongation rather than nucleation of αSN and has only a modest effect on the level of oligomerization. Furthermore, glycated αSN is not significantly incorporated into fibrils. For both MGO and ribose, we discovered that a level of ∼5 modifications per αSN is optimal for inhibition of elongation. The remaining sugars showed a weak but optimal inhibition at ∼2 modifications per αSN. We propose that this optimal level balances the affinity for the growing ends of the fibril (which decreases with the extent of modification) with the ability to block incorporation of subsequent αSN subunits (which increases with modification). Our results are not only relevant for other αSN PTMs but also for understanding PTMs affecting other fibrillogenic proteins and may thus open novel avenues for therapeutic intervention in protein aggregation disorders.
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107
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Cai W, Srivastava P, Feng D, Lin Y, Vanderburg CR, Xu Y, Mclean P, Frosch MP, Fisher DE, Schwarzschild MA, Chen X. Melanocortin 1 receptor activation protects against alpha-synuclein pathologies in models of Parkinson's disease. Mol Neurodegener 2022; 17:16. [PMID: 35197079 PMCID: PMC8867846 DOI: 10.1186/s13024-022-00520-4] [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] [Received: 08/23/2021] [Accepted: 02/11/2022] [Indexed: 12/02/2022] Open
Abstract
Background Epidemiological studies suggest a link between the melanoma-related pigmentation gene melanocortin 1 receptor (MC1R) and risk of Parkinson’s disease (PD). We previously showed that MC1R signaling can facilitate nigrostriatal dopaminergic neuron survival. The present study investigates the neuroprotective potential of MC1R against neurotoxicity induced by alpha-synuclein (αSyn), a key player in PD genetics and pathogenesis. Methods Nigral dopaminergic neuron toxicity induced by local overexpression of aSyn was assessed in mice that have an inactivating mutation of MC1R, overexpress its wild-type transgene, or were treated with MC1R agonists. The role of nuclear factor erythroid 2-related factor 2 (Nrf2) in MC1R-mediated protection against αSyn was characterized in vitro. Furthermore, MC1R expression was determined in human postmortem midbrain from patients with PD and unaffected subjects. Results Targeted expression of αSyn in the nigrostriatal pathway induced exacerbated synuclein pathologies in MC1R mutant mice, which were accompanied by neuroinflammation and altered Nrf2 responses, and reversed by the human MC1R transgene. Two MC1R agonists were neuroprotective against αSyn-induced dopaminergic neurotoxicity. In vitro experiments showed that Nrf2 was a necessary mediator of MC1R effects. Lastly, MC1R was present in dopaminergic neurons in the human substantia nigra and appeared to be reduced at the tissue level in PD patients. Conclusion Our study supports an interaction between MC1R and αSyn that can be mediated by neuronal MC1R possibly through Nrf2. It provides evidence for MC1R as a therapeutic target and a rationale for development of MC1R-activating strategies for PD. Supplementary Information The online version contains supplementary material available at 10.1186/s13024-022-00520-4.
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Affiliation(s)
- Waijiao Cai
- MassGeneral Institute for Neurodegenerative Disease, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, USA.,Department of Integrative Medicine, HuaShan Hospital, Institutes of Integrative Medicine, Fudan University, Shanghai, China
| | - Pranay Srivastava
- MassGeneral Institute for Neurodegenerative Disease, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, USA.,Aligning Science Across Parkinson's (ASAP) Collaborative Research Network, Chevy Chase, Towson, MD, USA
| | - Danielle Feng
- MassGeneral Institute for Neurodegenerative Disease, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, USA
| | - Yue Lin
- MassGeneral Institute for Neurodegenerative Disease, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, USA
| | - Charles R Vanderburg
- MassGeneral Institute for Neurodegenerative Disease, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, USA.,Harvard NeuroDiscovery Advanced Tissue Resource Center, Massachusetts General Hospital, Harvard Medical School, Boston, USA
| | - Yuehang Xu
- MassGeneral Institute for Neurodegenerative Disease, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, USA
| | | | - Matthew P Frosch
- MassGeneral Institute for Neurodegenerative Disease, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, USA.,Harvard NeuroDiscovery Advanced Tissue Resource Center, Massachusetts General Hospital, Harvard Medical School, Boston, USA.,Neuropathology Service, Massachusetts General Hospital, Harvard Medical School, Boston, USA
| | - David E Fisher
- Cutaneous Biology Research Center, Department of Dermatology, Massachusetts General Hospital, Harvard Medical School, Boston, USA
| | - Michael A Schwarzschild
- MassGeneral Institute for Neurodegenerative Disease, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, USA.,Aligning Science Across Parkinson's (ASAP) Collaborative Research Network, Chevy Chase, Towson, MD, USA
| | - Xiqun Chen
- MassGeneral Institute for Neurodegenerative Disease, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, USA. .,Aligning Science Across Parkinson's (ASAP) Collaborative Research Network, Chevy Chase, Towson, MD, USA.
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108
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Lima VDA, Esquinelato R, Carmo-Gonçalves P, Nascimento LAD, Lee H, Eliezer D, Romão L, Follmer C. The dopamine receptor agonist apomorphine stabilizes neurotoxic α-synuclein oligomers. FEBS Lett 2022; 596:309-322. [PMID: 34928512 PMCID: PMC8972942 DOI: 10.1002/1873-3468.14263] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Revised: 11/13/2021] [Accepted: 12/10/2021] [Indexed: 02/03/2023]
Abstract
The misfolding and aggregation of the protein α-synuclein (aSyn) into potentially neurotoxic oligomers is believed to play a pivotal role in the neuropathogenesis of Parkinson's disease (PD). Herein, we explore how apomorphine (Apo), a nonselective dopamine D1 and D2 receptor agonist utilized in the therapy for PD, affects the aggregation and toxicity of aSyn in vitro. Our data indicated that Apo inhibits aSyn fibrillation leading to the formation of large oligomeric species (Apo-aSyn-O), which exhibit remarkable toxicity in mesencephalic dopaminergic neurons in primary cultures. Interestingly, purified Apo-aSyn-O, even at very low concentrations, seems to be capable of converting unmodified aSyn monomer into neurotoxic species. Collectively, our findings warn for a possible dangerous effect of Apo on aSyn misfolding/aggregation pathway.
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Affiliation(s)
- Vanderlei de Araujo Lima
- Department of Physical Chemistry, Federal University of Rio de Janeiro, Brazil
- Graduate Program in Chemistry, Institute of Chemistry, Federal University of Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, Brazil
| | - Rodrigo Esquinelato
- Department of Physical Chemistry, Federal University of Rio de Janeiro, Brazil
| | - Phelippe Carmo-Gonçalves
- Department of Physical Chemistry, Federal University of Rio de Janeiro, Brazil
- Graduate Program in Chemistry, Institute of Chemistry, Federal University of Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, Brazil
| | | | - Hudson Lee
- Department of Biochemistry, Weill Cornell Medical College, Cornell University, New York, NY, USA
| | - David Eliezer
- Department of Biochemistry, Weill Cornell Medical College, Cornell University, New York, NY, USA
| | - Luciana Romão
- Institute of Biomedical Sciences, Federal University of Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, Brazil
| | - Cristian Follmer
- Department of Physical Chemistry, Federal University of Rio de Janeiro, Brazil
- Graduate Program in Chemistry, Institute of Chemistry, Federal University of Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, Brazil
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109
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Uçar B, Stefanova N, Humpel C. Spreading of Aggregated α-Synuclein in Sagittal Organotypic Mouse Brain Slices. Biomolecules 2022; 12:biom12020163. [PMID: 35204664 PMCID: PMC8961638 DOI: 10.3390/biom12020163] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Revised: 01/14/2022] [Accepted: 01/17/2022] [Indexed: 02/01/2023] Open
Abstract
The accumulation of α-synuclein (α-syn) in the brain plays a role in synucleinopathies and it is hypothesized to spread in a prion-like fashion between connected brain regions. In the present study, we aim to investigate this spreading in well-characterized sagittal organotypic whole brain slices taken from postnatal wild type (WT) and transgenic mice overexpressing human α-syn under the promoter of proteolipid protein (PLP). Collagen hydrogels were loaded with monomers of human α-syn, as well as human and mouse pre-formed fibrils (PFFs), to allow local application and slow release. The spreading of α-syn was evaluated in different brain regions by immunohistochemistry for total α-syn and α-syn phosphorylated at the serine129 position (α-syn-P). The application of human and mouse PFFs of α-syn caused the aggregation and spreading of α-syn-P in the brain slices, which was pronounced the most at the region of hydrogel application and surrounding striatum, as well as along the median forebrain bundle. The organotypic slices from transgenic mice showed significantly more α-syn pathology than those from WT mice. The present study demonstrates that seeding with α-syn PFFs but not monomers induced intracellular α-syn pathology, which was significantly more prominent in brain slices with α-syn overexpression. This is consistent with the prion-like spreading theory of α-syn aggregates. The sagittal whole brain slices characterized in this study carry the potential to be used as a novel model to study α-syn pathology.
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Affiliation(s)
- Buket Uçar
- Laboratory of Psychiatry and Experimental Alzheimer’s Research, Department of Psychiatry and Psychotherapy, Medical University of Innsbruck, Anichstrasse 35, A-6020 Innsbruck, Austria;
| | - Nadia Stefanova
- Laboratory for Translational Neurodegeneration Research, Division of Neurobiology, Department of Neurology, Medical University of Innsbruck, Innrain 66, A-6020 Innsbruck, Austria;
| | - Christian Humpel
- Laboratory of Psychiatry and Experimental Alzheimer’s Research, Department of Psychiatry and Psychotherapy, Medical University of Innsbruck, Anichstrasse 35, A-6020 Innsbruck, Austria;
- Correspondence: ; Tel.: +43-512-504-23712; Fax: +43-512-504-23713
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110
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Chiu SY, Bowers D, Armstrong MJ. Lewy Body Dementias: Controversies and Drug Development. Neurotherapeutics 2022; 19:55-67. [PMID: 34859379 PMCID: PMC9130410 DOI: 10.1007/s13311-021-01161-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/06/2021] [Indexed: 01/03/2023] Open
Abstract
Lewy body dementia (LBD) is one of the most common neurodegenerative dementias. Clinical trials for symptomatic and disease-modifying therapies in LBD remain a national research priority, but there are many challenges in both past and active drug developments in LBD. This review highlights the controversies in picking the appropriate populations, interventions, target selections, and outcome measures, which are all critical components of clinical trial implementation in LBD. The heterogeneity of LBD neuropathology and clinical presentations, limited understanding of core features such as cognitive fluctuations, and lack of validated LBD-specific outcome measures and biomarkers represent some of the major challenges in LBD trials.
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Affiliation(s)
- Shannon Y Chiu
- Department of Neurology, University of Florida, PO Box 100268, Gainesville, FL, 32611, USA.
| | - Dawn Bowers
- Department of Clinical and Health Psychology, University of Florida, Gainesville, FL, 32603, USA
| | - Melissa J Armstrong
- Department of Neurology, University of Florida, PO Box 100268, Gainesville, FL, 32611, USA
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111
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The Alpha-Synuclein RT-QuIC Products Generated by the Olfactory Mucosa of Patients with Parkinson’s Disease and Multiple System Atrophy Induce Inflammatory Responses in SH-SY5Y Cells. Cells 2021; 11:cells11010087. [PMID: 35011649 PMCID: PMC8750063 DOI: 10.3390/cells11010087] [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: 10/15/2021] [Revised: 12/22/2021] [Accepted: 12/24/2021] [Indexed: 11/28/2022] Open
Abstract
Parkinson’s disease (PD) and multiple system atrophy (MSA) are caused by two distinct strains of disease-associated α-synuclein (αSynD). Recently, we have shown that olfactory mucosa (OM) samples of patients with PD and MSA can seed the aggregation of recombinant α-synuclein by means of Real-Time Quaking-Induced Conversion (αSyn_RT-QuIC). Remarkably, the biochemical and morphological properties of the final α-synuclein aggregates significantly differed between PD and MSA seeded samples. Here, these aggregates were given to neuron-like differentiated SH-SY5Y cells and distinct inflammatory responses were observed. To deepen whether the morphological features of α-synuclein aggregates were responsible for this variable SH-SY5Y inflammatory response, we generated three biochemically and morphologically distinct α-synuclein aggregates starting from recombinant α-synuclein that were used to seed αSyn_RT-QuIC reaction; the final reaction products were used to stimulate SH-SY5Y cells. Our study showed that, in contrast to OM samples of PD and MSA patients, the artificial aggregates did not transfer their distinctive features to the αSyn_RT-QuIC products and the latter induced analogous inflammatory responses in cells. Thus, the natural composition of the αSynD strains but also other specific factors in OM tissue can substantially modulate the biochemical, morphological and inflammatory features of the αSyn_RT-QuIC products.
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112
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Dey A, Vishvakarma V, Das A, Kallianpur M, Dey S, Joseph R, Maiti S. Single Molecule Measurements of the Accessibility of Molecular Surfaces. Front Mol Biosci 2021; 8:745313. [PMID: 34926574 PMCID: PMC8672140 DOI: 10.3389/fmolb.2021.745313] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Accepted: 11/03/2021] [Indexed: 11/13/2022] Open
Abstract
An important measure of the conformation of protein molecules is the degree of surface exposure of its specific segments. However, this is hard to measure at the level of individual molecules. Here, we combine single molecule photobleaching (smPB, which resolves individual photobleaching steps of single molecules) and fluorescence quenching techniques to measure the accessibility of individual fluorescently labeled protein molecules to quencher molecules in solution. A quencher can reduce the time a fluorophore spends in the excited state, increasing its photostability under continuous irradiation. Consequently, the photo-bleaching step length would increase, providing a measure for the accessibility of the fluorophore to the solvent. We demonstrate the method by measuring the bleaching step-length increase in a lipid, and also in a lipid-anchored peptide (both labelled with rhodamine-B and attached to supported lipid bilayers). The fluorophores in both molecules are expected to be solvent-exposed. They show a near two-fold increase in the step length upon incubation with 5 mM tryptophan (a quencher of rhodamine-B), validating our approach. A population distribution plot of step lengths before and after addition of tryptophan show that the increase is not always homogenous. Indeed there are different species present with differential levels of exposure. We then apply this technique to determine the solvent exposure of membrane-attached N-terminus labelled amylin (h-IAPP, an amyloid associated with Type II diabetes) whose interaction with lipid bilayers is poorly understood. hIAPP shows a much smaller increase of the step length, signifying a lower level of solvent exposure of its N-terminus. Analysis of results from individual molecules and step length distribution reveal that there are at least two different conformers of amylin in the lipid bilayer. Our results show that our method (“Q-SLIP”, Quenching-induced Step Length increase in Photobleaching) provides a simple route to probe the conformational states of membrane proteins at a single molecule level.
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Affiliation(s)
- Arpan Dey
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Mumbai, India
| | - Vicky Vishvakarma
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Mumbai, India
| | - Anirban Das
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Mumbai, India
| | - Mamata Kallianpur
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Mumbai, India
| | - Simli Dey
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Mumbai, India
| | - Roshni Joseph
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Mumbai, India
| | - Sudipta Maiti
- Department of Chemical Sciences, Tata Institute of Fundamental Research, Mumbai, India
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113
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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: 25] [Impact Index Per Article: 8.3] [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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牟 斐, 陈 曦, 杜 希, 焦 倩, 毕 明, 姜 宏. [Regulatory mechanism of interferon regulatory factor 1 by α-synuclein in mouse Parkinson's disease model]. NAN FANG YI KE DA XUE XUE BAO = JOURNAL OF SOUTHERN MEDICAL UNIVERSITY 2021; 41:1641-1648. [PMID: 34916189 PMCID: PMC8685704 DOI: 10.12122/j.issn.1673-4254.2021.11.07] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Indexed: 06/14/2023]
Abstract
OBJECTIVE To investigate the molecular mechanism by which α-synuclein (α-Syn) regulates interferon regulatory factor 1 (IRF-1) expression. METHODS SH-SY5Y cells overexpressing α-Syn and transgenic mouse model carrying human α-Syn gene with A53T mutation (3 and 6 months old) were examined for IRF-1 mRNA and protein expressions using real-time PCR and Western blotting, respectively. The subcellular localization of IRF-1 was determined with immunofluorescence staining and cytoplasmic/nuclear protein isolation. The optimal concentrations of the proteasome inhibitor MG132 (0.01-2.0 μmol/L) and lysosomal inhibitor chloroquine (5-200 μmol/L) for treatment of SH-SY5Y cells for 24 h were determined by examining the cell viability. SH-SY5Y cells were treated with 0.2 μmol/L MG132 and 30 μmol/L chloroquine for 24 h (the maximum dose that did not cause cell damage), and the changes of IRF-1 protein expressions was analyzed. The effects of α-Syn on MDM2 protein expression and IRF-1 ubiquitylation were analyzed using Western blotting and ubiquitylation assay. RESULTS α-Syn overexpression did not affect the mRNA level of IRF-1 but significantly increased its protein level (P < 0.01). In α-Synoverexpressing SH-SY5Y cells, IRF-1 translocation was observed from the cytoplasm to the nucleus (P < 0.001). Treatment of the cells with 0.2 μmol/L MG132 significantly aggravated α-Syn-induced increase of IRF-1 protein expression (P < 0.01) while 30 μmol/L chloroquine produced no significant changes in IRF-1 level. α-Syn overexpression caused an obvious decrease of MDM2 protein level and further inhibited the ubiquitylation of IRF-1 (P < 0.01). CONCLUSION α-Syn blocks MDM2-mediated ubiquitylation of IRF-1 through ubiquitin proteasome pathway, thereby enhancing IRF-1 protein expression.
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Affiliation(s)
- 斐斐 牟
- />青岛大学国家生理学重点(培育)学科,山东 青岛 266071State Key Disciplines of Physiology (Incubation), Department of Physiology, Qingdao University, Qingdao 266071, China
| | - 曦 陈
- />青岛大学国家生理学重点(培育)学科,山东 青岛 266071State Key Disciplines of Physiology (Incubation), Department of Physiology, Qingdao University, Qingdao 266071, China
| | - 希恂 杜
- />青岛大学国家生理学重点(培育)学科,山东 青岛 266071State Key Disciplines of Physiology (Incubation), Department of Physiology, Qingdao University, Qingdao 266071, China
| | - 倩 焦
- />青岛大学国家生理学重点(培育)学科,山东 青岛 266071State Key Disciplines of Physiology (Incubation), Department of Physiology, Qingdao University, Qingdao 266071, China
| | - 明霞 毕
- />青岛大学国家生理学重点(培育)学科,山东 青岛 266071State Key Disciplines of Physiology (Incubation), Department of Physiology, Qingdao University, Qingdao 266071, China
| | - 宏 姜
- />青岛大学国家生理学重点(培育)学科,山东 青岛 266071State Key Disciplines of Physiology (Incubation), Department of Physiology, Qingdao University, Qingdao 266071, China
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115
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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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Dubackic M, Idini I, Lattanzi V, Liu Y, Martel A, Terry A, Haertlein M, Devos JM, Jackson A, Sparr E, Linse S, Olsson U. On the Cluster Formation of α-Synuclein Fibrils. Front Mol Biosci 2021; 8:768004. [PMID: 34738016 PMCID: PMC8560691 DOI: 10.3389/fmolb.2021.768004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Accepted: 09/30/2021] [Indexed: 12/05/2022] Open
Abstract
The dense accumulation of α-Synuclein fibrils in neurons is considered to be strongly associated with Parkinson’s disease. These intracellular inclusions, called Lewy bodies, also contain significant amounts of lipids. To better understand such accumulations, it should be important to study α-Synuclein fibril formation under conditions where the fibrils lump together, mimicking what is observed in Lewy bodies. In the present study, we have therefore investigated the overall structural arrangements of α-synuclein fibrils, formed under mildly acidic conditions, pH = 5.5, in pure buffer or in the presence of various model membrane systems, by means of small-angle neutron scattering (SANS). At this pH, α-synuclein fibrils are colloidally unstable and aggregate further into dense clusters. SANS intensities show a power law dependence on the scattering vector, q, indicating that the clusters can be described as mass fractal aggregates. The experimentally observed fractal dimension was d = 2.6 ± 0.3. We further show that this fractal dimension can be reproduced using a simple model of rigid-rod clusters. The effect of dominatingly attractive fibril-fibril interactions is discussed within the context of fibril clustering in Lewy body formation.
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Affiliation(s)
- Marija Dubackic
- Division of Physical Chemistry, Department of Chemistry, Lund University, Lund, Sweden
| | - Ilaria Idini
- Division of Physical Chemistry, Department of Chemistry, Lund University, Lund, Sweden
| | - Veronica Lattanzi
- Division of Physical Chemistry, Department of Chemistry, Lund University, Lund, Sweden.,Division of Biochemistry and Structural Biology, Department of Chemistry, Lund University, Lund, Sweden
| | - Yun Liu
- Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, MD, United States.,Chemical and Biomolecular Engineering Department, University of Delaware, Newark, DE, United States
| | | | - Ann Terry
- ISIS Neutron and Muon Source, Harwell Oxford, Didcot, United Kingdom.,Max IV Laboratory, Lund University, Lund, Sweden
| | | | | | - Andrew Jackson
- Division of Physical Chemistry, Department of Chemistry, Lund University, Lund, Sweden.,European Spallation Source, Lund, Sweden
| | - Emma Sparr
- Division of Biochemistry and Structural Biology, Department of Chemistry, Lund University, Lund, Sweden
| | - Sara Linse
- Division of Biochemistry and Structural Biology, Department of Chemistry, Lund University, Lund, Sweden
| | - Ulf Olsson
- Division of Physical Chemistry, Department of Chemistry, Lund University, Lund, Sweden
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117
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Olsen AL, Feany MB. Parkinson's disease risk genes act in glia to control neuronal α-synuclein toxicity. Neurobiol Dis 2021; 159:105482. [PMID: 34390834 PMCID: PMC8502212 DOI: 10.1016/j.nbd.2021.105482] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2021] [Revised: 08/04/2021] [Accepted: 08/09/2021] [Indexed: 11/18/2022] Open
Abstract
Idiopathic Parkinson's disease is the second most common neurodegenerative disease and is estimated to be approximately 30% heritable. Genome wide association studies have revealed numerous loci associated with risk of development of Parkinson's disease. The majority of genes identified in these studies are expressed in glia at either similar or greater levels than their expression in neurons, suggesting that glia may play a role in Parkinson's disease pathogenesis. The role of individual glial risk genes in Parkinson's disease development or progression is unknown, however. We hypothesized that some Parkinson's disease risk genes exert their effects through glia. We developed a Drosophila model of α-synucleinopathy in which we can independently manipulate gene expression in neurons and glia. Human wild type α-synuclein is expressed in all neurons, and these flies develop the hallmarks of Parkinson's disease, including motor impairment, death of dopaminergic and other neurons, and α-synuclein aggregation. In these flies, we performed a candidate genetic screen, using RNAi to knockdown 14 well-validated Parkinson's disease risk genes in glia and measuring the effect on locomotion in order to identify glial modifiers of the α-synuclein phenotype. We identified 4 modifiers: aux, Lrrk, Ric, and Vps13, orthologs of the human genes GAK, LRRK2, RIT2, and VPS13C, respectively. Knockdown of each gene exacerbated neurodegeneration as measured by total and dopaminergic neuron loss. Knockdown of each modifier also increased α-synuclein oligomerization. These results suggest that some Parkinson's disease risk genes exert their effects in glia and that glia can influence neuronal α-synuclein proteostasis in a non-cell-autonomous fashion. Further, this study provides proof of concept that our novel Drosophila α-synucleinopathy model can be used to study glial modifier genes, paving the way for future large unbiased screens to identify novel glial risk factors that contribute to PD risk and progression.
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Affiliation(s)
- Abby L Olsen
- Department of Neurology, Brigham and Women's Hospital, Massachusetts General Hospital, Harvard Medical School, United States of America; Department of Pathology, Brigham and Women's Hospital, Harvard Medical School, United States of America
| | - Mel B Feany
- Department of Neurology, Brigham and Women's Hospital, Massachusetts General Hospital, Harvard Medical School, United States of America; Department of Pathology, Brigham and Women's Hospital, Harvard Medical School, United States of America.
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118
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Bido S, Muggeo S, Massimino L, Marzi MJ, Giannelli SG, Melacini E, Nannoni M, Gambarè D, Bellini E, Ordazzo G, Rossi G, Maffezzini C, Iannelli A, Luoni M, Bacigaluppi M, Gregori S, Nicassio F, Broccoli V. Microglia-specific overexpression of α-synuclein leads to severe dopaminergic neurodegeneration by phagocytic exhaustion and oxidative toxicity. Nat Commun 2021; 12:6237. [PMID: 34716339 PMCID: PMC8556263 DOI: 10.1038/s41467-021-26519-x] [Citation(s) in RCA: 78] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Accepted: 10/12/2021] [Indexed: 12/14/2022] Open
Abstract
Recent findings in human samples and animal models support the involvement of inflammation in the development of Parkinson's disease. Nevertheless, it is currently unknown whether microglial activation constitutes a primary event in neurodegeneration. We generated a new mouse model by lentiviral-mediated selective α-synuclein (αSYN) accumulation in microglial cells. Surprisingly, these mice developed progressive degeneration of dopaminergic (DA) neurons without endogenous αSYN aggregation. Transcriptomics and functional assessment revealed that αSYN-accumulating microglial cells developed a strong reactive state with phagocytic exhaustion and excessive production of oxidative and proinflammatory molecules. This inflammatory state created a molecular feed-forward vicious cycle between microglia and IFNγ-secreting immune cells infiltrating the brain parenchyma. Pharmacological inhibition of oxidative and nitrosative molecule production was sufficient to attenuate neurodegeneration. These results suggest that αSYN accumulation in microglia induces selective DA neuronal degeneration by promoting phagocytic exhaustion, an excessively toxic environment and the selective recruitment of peripheral immune cells.
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Affiliation(s)
- Simone Bido
- Division of Neuroscience, IRCCS San Raffaele Scientific Institute, 20132, Milan, Italy
| | - Sharon Muggeo
- Division of Neuroscience, IRCCS San Raffaele Scientific Institute, 20132, Milan, Italy
| | - Luca Massimino
- Division of Neuroscience, IRCCS San Raffaele Scientific Institute, 20132, Milan, Italy
| | - Matteo Jacopo Marzi
- Center for Genomic Science of IIT@SEMM, Istituto Italiano di Tecnologia (IIT), 20139, Milan, Italy
| | - Serena Gea Giannelli
- Division of Neuroscience, IRCCS San Raffaele Scientific Institute, 20132, Milan, Italy
| | - Elena Melacini
- Division of Neuroscience, IRCCS San Raffaele Scientific Institute, 20132, Milan, Italy
- National Research Council (CNR), Institute of Neuroscience, 20129, Milan, Italy
| | - Melania Nannoni
- Division of Neuroscience, IRCCS San Raffaele Scientific Institute, 20132, Milan, Italy
| | - Diana Gambarè
- Division of Neuroscience, IRCCS San Raffaele Scientific Institute, 20132, Milan, Italy
| | - Edoardo Bellini
- Division of Neuroscience, IRCCS San Raffaele Scientific Institute, 20132, Milan, Italy
| | - Gabriele Ordazzo
- Division of Neuroscience, IRCCS San Raffaele Scientific Institute, 20132, Milan, Italy
| | - Greta Rossi
- Division of Neuroscience, IRCCS San Raffaele Scientific Institute, 20132, Milan, Italy
| | - Camilla Maffezzini
- Division of Neuroscience, IRCCS San Raffaele Scientific Institute, 20132, Milan, Italy
| | - Angelo Iannelli
- Division of Neuroscience, IRCCS San Raffaele Scientific Institute, 20132, Milan, Italy
- National Research Council (CNR), Institute of Neuroscience, 20129, Milan, Italy
| | - Mirko Luoni
- Division of Neuroscience, IRCCS San Raffaele Scientific Institute, 20132, Milan, Italy
| | - Marco Bacigaluppi
- Division of Neuroscience, Institute of Experimental Neurology, IRCCS San Raffaele Scientific Institute, Milan, Italy
| | - Silvia Gregori
- San Raffaele Telethon Institute for Gene Therapy, IRCCS San Raffaele Scientific Institute, Milan, Italy
| | - Francesco Nicassio
- Center for Genomic Science of IIT@SEMM, Istituto Italiano di Tecnologia (IIT), 20139, Milan, Italy
| | - Vania Broccoli
- Division of Neuroscience, IRCCS San Raffaele Scientific Institute, 20132, Milan, Italy.
- National Research Council (CNR), Institute of Neuroscience, 20129, Milan, Italy.
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119
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Mechanistic Insight from Preclinical Models of Parkinson's Disease Could Help Redirect Clinical Trial Efforts in GDNF Therapy. Int J Mol Sci 2021; 22:ijms222111702. [PMID: 34769132 PMCID: PMC8583859 DOI: 10.3390/ijms222111702] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2021] [Revised: 10/23/2021] [Accepted: 10/25/2021] [Indexed: 11/16/2022] Open
Abstract
Parkinson’s disease (PD) is characterized by four pathognomonic hallmarks: (1) motor and non-motor deficits; (2) neuroinflammation and oxidative stress; (3) pathological aggregates of the α-synuclein (α-syn) protein; (4) neurodegeneration of the nigrostriatal system. Recent evidence sustains that the aggregation of pathological α-syn occurs in the early stages of the disease, becoming the first trigger of neuroinflammation and subsequent neurodegeneration. Thus, a therapeutic line aims at striking back α-synucleinopathy and neuroinflammation to impede neurodegeneration. Another therapeutic line is restoring the compromised dopaminergic system using neurotrophic factors, particularly the glial cell-derived neurotrophic factor (GDNF). Preclinical studies with GDNF have provided encouraging results but often lack evaluation of anti-α-syn and anti-inflammatory effects. In contrast, clinical trials have yielded imprecise results and have reported the emergence of severe side effects. Here, we analyze the discrepancy between preclinical and clinical outcomes, review the mechanisms of the aggregation of pathological α-syn, including neuroinflammation, and evaluate the neurorestorative properties of GDNF, emphasizing its anti-α-syn and anti-inflammatory effects in preclinical and clinical trials.
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120
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Lorentzon E, Horvath I, Kumar R, Rodrigues JI, Tamás MJ, Wittung-Stafshede P. Effects of the Toxic Metals Arsenite and Cadmium on α-Synuclein Aggregation In Vitro and in Cells. Int J Mol Sci 2021; 22:ijms222111455. [PMID: 34768886 PMCID: PMC8584132 DOI: 10.3390/ijms222111455] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2021] [Revised: 10/21/2021] [Accepted: 10/21/2021] [Indexed: 11/21/2022] Open
Abstract
Exposure to heavy metals, including arsenic and cadmium, is associated with neurodegenerative disorders such as Parkinson’s disease. However, the mechanistic details of how these metals contribute to pathogenesis are not well understood. To search for underlying mechanisms involving α-synuclein, the protein that forms amyloids in Parkinson’s disease, we here assessed the effects of arsenic and cadmium on α-synuclein amyloid formation in vitro and in Saccharomyces cerevisiae (budding yeast) cells. Atomic force microscopy experiments with acetylated human α-synuclein demonstrated that amyloid fibers formed in the presence of the metals have a different fiber pitch compared to those formed without metals. Both metal ions become incorporated into the amyloid fibers, and cadmium also accelerated the nucleation step in the amyloid formation process, likely via binding to intermediate species. Fluorescence microscopy analyses of yeast cells expressing fluorescently tagged α-synuclein demonstrated that arsenic and cadmium affected the distribution of α-synuclein aggregates within the cells, reduced aggregate clearance, and aggravated α-synuclein toxicity. Taken together, our in vitro data demonstrate that interactions between these two metals and α-synuclein modulate the resulting amyloid fiber structures, which, in turn, might relate to the observed effects in the yeast cells. Whilst our study advances our understanding of how these metals affect α-synuclein biophysics, further in vitro characterization as well as human cell studies are desired to fully appreciate their role in the progression of Parkinson’s disease.
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Affiliation(s)
- Emma Lorentzon
- Department of Chemistry and Molecular Biology, University of Gothenburg, SE-405 30 Gothenburg, Sweden; (E.L.); (J.I.R.)
| | - Istvan Horvath
- Department of Biology and Biological Engineering, Chalmers University of Technology, SE-412 96 Gothenburg, Sweden; (I.H.); (R.K.)
| | - Ranjeet Kumar
- Department of Biology and Biological Engineering, Chalmers University of Technology, SE-412 96 Gothenburg, Sweden; (I.H.); (R.K.)
| | - Joana Isabel Rodrigues
- Department of Chemistry and Molecular Biology, University of Gothenburg, SE-405 30 Gothenburg, Sweden; (E.L.); (J.I.R.)
| | - Markus J. Tamás
- Department of Chemistry and Molecular Biology, University of Gothenburg, SE-405 30 Gothenburg, Sweden; (E.L.); (J.I.R.)
- Correspondence: (M.J.T.); (P.W.-S.)
| | - Pernilla Wittung-Stafshede
- Department of Biology and Biological Engineering, Chalmers University of Technology, SE-412 96 Gothenburg, Sweden; (I.H.); (R.K.)
- Correspondence: (M.J.T.); (P.W.-S.)
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121
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Shan FY, Fung KM, Zieneldien T, Kim J, Cao C, Huang JH. Examining the Toxicity of α-Synuclein in Neurodegenerative Disorders. Life (Basel) 2021; 11:life11111126. [PMID: 34833002 PMCID: PMC8621244 DOI: 10.3390/life11111126] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Revised: 10/14/2021] [Accepted: 10/19/2021] [Indexed: 12/20/2022] Open
Abstract
Simple Summary Neurodegenerative disorders are complex disorders that display a variety of clinical manifestations. The second-most common neurodegenerative disorder is Parkinson’s disease, and the leading pathological protein of the disorder is considered to be α-synuclein. Nonetheless, α-synuclein accumulation also seems to result in multiple system atrophy and dementia with Lewy bodies. In order to obtain a more proficient understanding in the pathological progression of these synucleinopathies, it is crucial to observe the post-translational modifications of α-synuclein and the conformations of α-synuclein, as well as its role in the dysfunction of cellular pathways. Abstract α-synuclein is considered the main pathological protein in a variety of neurodegenerative disorders, such as Parkinson’s disease, multiple system atrophy, and dementia with Lewy bodies. As of now, numerous studies have been aimed at examining the post-translational modifications of α-synuclein to determine their effects on α-synuclein aggregation, propagation, and oligomerization, as well as the potential cellular pathway dysfunctions caused by α-synuclein, to determine the role of the protein in disease progression. Furthermore, α-synuclein also appears to contribute to the fibrilization of tau and amyloid beta, which are crucial proteins in Alzheimer’s disease, advocating for α-synuclein’s preeminent role in neurodegeneration. Due to this, investigating the mechanisms of toxicity of α-synuclein in neurodegeneration may lead to a more proficient understanding of the timeline progression in neurodegenerative synucleinopathies and could thereby lead to the development of potent targeted therapies.
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Affiliation(s)
- Frank Y. Shan
- Department of Anatomic Pathology, Baylor Scott & White Medical Center, College of Medicine, Texas A&M University, Temple, TX 76508, USA
- Correspondence: (F.Y.S.); (T.Z.)
| | - Kar-Ming Fung
- Department of Pathology, University of Oklahoma Medical Center, University of Oklahoma, Norman, OK 73019, USA;
| | - Tarek Zieneldien
- Department of Pharmaceutical Sciences, Taneja College of Pharmacy, University of South Florida, Tampa, FL 33620, USA; (J.K.); (C.C.)
- Correspondence: (F.Y.S.); (T.Z.)
| | - Janice Kim
- Department of Pharmaceutical Sciences, Taneja College of Pharmacy, University of South Florida, Tampa, FL 33620, USA; (J.K.); (C.C.)
| | - Chuanhai Cao
- Department of Pharmaceutical Sciences, Taneja College of Pharmacy, University of South Florida, Tampa, FL 33620, USA; (J.K.); (C.C.)
| | - Jason H. Huang
- Department of Neurosurgery, Baylor Scott & White Medical Center, College of Medicine, Texas A&M University, Temple, TX 76508, USA;
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Chen DD, Gao LP, Wu YZ, Chen J, Hu C, Xiao K, Chen C, Shi Q, Dong XP. Accumulation of Prion and Abnormal Prion Protein Induces Hyperphosphorylation of α-Synuclein in the Brain Tissues from Prion Diseases and in the Cultured Cells. ACS Chem Neurosci 2021; 12:3838-3854. [PMID: 34595918 DOI: 10.1021/acschemneuro.1c00240] [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] [Indexed: 12/12/2022] Open
Abstract
Prion disease (PrD) and Parkinson's disease (PD) are neurodegenerative diseases characterized by aggregation of misfolded proteins in brain tissues, including protease-resistant prion protein (PrPSc) in PrD and α-synuclein in PD. In recent years, overlap of these two proteins has attracted increased attention, and cross-seeding of prion proteins by aggregated α-synuclein has been proposed. However, the changes in α-synuclein after prion infection are still unclear. In this study, we showed that α-synuclein expression was significantly decreased in the brains of prion-infected rodent models, in the SMB-S15 cell line, which exhibits persistent prion replication, and in the brains of humans with PrDs. Meanwhile, α-synuclein phosphorylated at serine 129(p(S129)-α-synuclein) was significantly increased in the brains of scrapie-infected mice and prion-infected SMB-S15 cells. The increased p(S129)-α-synuclein colocalized with GFAP- and NeuN-positive cells in the brains of scrapie-infected mice. p(S129)-α-synuclein was also observed in the cytoplasm of SMB-S15 and HEK-293 cells transiently expressing an abnormal form of prion protein (Cyto-PrP). Molecular interactions between PrP and α-synuclein were detected in recombinant proteins, normal and prion-infected brain tissues, and cultured cells. The increased p(S129)-α-synuclein colocalized with PrP signals from prion-infected SMB-S15 and HEK-293 cells expressing Cyto-PrP. Moreover, increased morphological colocalization of p(S129)-α-synuclein with mitochondrial markers was also detected in the two cell types. Our results indicate that prion replication and accumulation in cells and brains induce hyperphosphorylation of α-synuclein, particularly at S129, which may aggravate mitochondrial damage and facilitate α-synuclein aggregation in the central nervous system tissues from PrDs.
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Affiliation(s)
- Dong-Dong Chen
- State Key Laboratory for Infectious Disease Prevention and Control, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases (Zhejiang University), National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China
| | - Li-Ping Gao
- State Key Laboratory for Infectious Disease Prevention and Control, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases (Zhejiang University), National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China
| | - Yue-Zhang Wu
- State Key Laboratory for Infectious Disease Prevention and Control, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases (Zhejiang University), National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China
| | - Jia Chen
- State Key Laboratory for Infectious Disease Prevention and Control, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases (Zhejiang University), National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China
| | - Chao Hu
- State Key Laboratory for Infectious Disease Prevention and Control, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases (Zhejiang University), National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China
| | - Kang Xiao
- State Key Laboratory for Infectious Disease Prevention and Control, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases (Zhejiang University), National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China
| | - Cao Chen
- State Key Laboratory for Infectious Disease Prevention and Control, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases (Zhejiang University), National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China
- Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan 420115, China
| | - Qi Shi
- State Key Laboratory for Infectious Disease Prevention and Control, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases (Zhejiang University), National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China
- China Academy of Chinese Medical Sciences, Beijing 100700, China
| | - Xiao-Ping Dong
- State Key Laboratory for Infectious Disease Prevention and Control, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases (Zhejiang University), National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China
- Center for Global Public Health, Chinese Center for Disease Control and Prevention, Beijing 102206, China
- Center for Biosafety Mega-Science, Chinese Academy of Sciences, Wuhan 420115, China
- China Academy of Chinese Medical Sciences, Beijing 100700, China
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Chau E, Kim H, Shin J, Martinez A, Kim JR. Inhibition of alpha-synuclein aggregation by AM17, a synthetic resveratrol derivative. Biochem Biophys Res Commun 2021; 574:85-90. [PMID: 34454326 DOI: 10.1016/j.bbrc.2021.08.049] [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: 07/02/2021] [Revised: 07/29/2021] [Accepted: 08/18/2021] [Indexed: 10/20/2022]
Abstract
Parkinson's disease (PD) is linked to the aberrant self-assembly of the amyloid protein, α-synuclein (αS), where αS monomers aggregate to form oligomers and fibrils. Out of the three conformers, αS oligomers are the major toxic agents in PD, while αS fibrils may work as a reservoir for toxic oligomeric conformers. Thus, compounds that inhibit aggregation of αS monomers and disaggregate αS oligomers and fibrils may serve as therapeutic agents against PD. In this regard, resveratrol and its synthetic derivatives (e.g., AM17, which contains a copper ion-selective ionophoric motif) have previously been examined for their inhibitory effects on aggregation of amyloid proteins, such as the β-amyloid peptide implicated in Alzheimer's disease. In the current study, we employed an array of experimental tools, such as Thioflavin T fluorescence, transmission electron microscopy, immuno-dot blot assays, SDS- and native-PAGE, and circular dichroism, to determine the impact of AM17 and resveratrol on αS aggregation. To the best of our knowledge, we show for the first time that AM17 not only inhibits aggregation of αS monomers but also disaggregates αS oligomers and fibrils, independent of the copper ions. Similar αS aggregation inhibitory effects were observed with resveratrol only in the presence of the copper ion. The present study supports the high promise of applicability of AM17 as an effective amyloid aggregation inhibitor for various conformers and protein sequences.
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Affiliation(s)
- Edward Chau
- Department of Chemical and Biomolecular Engineering, New York University, 6 MetroTech Center, Brooklyn, NY, 11201, USA
| | - Hyunjoo Kim
- Department of Chemical and Biomolecular Engineering, New York University, 6 MetroTech Center, Brooklyn, NY, 11201, USA
| | - Jineun Shin
- Department of Biomedical Engineering, New York University, 6 MetroTech Center, Brooklyn, NY, 11201, USA
| | - Alberto Martinez
- Department of Chemistry, New York City College of Technology, 300 Jay St, Brooklyn, NY, 11201, USA
| | - Jin Ryoun Kim
- Department of Chemical and Biomolecular Engineering, New York University, 6 MetroTech Center, Brooklyn, NY, 11201, USA.
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Mohamed NV, Sirois J, Ramamurthy J, Mathur M, Lépine P, Deneault E, Maussion G, Nicouleau M, Chen CXQ, Abdian N, Soubannier V, Cai E, Nami H, Thomas RA, Wen D, Tabatabaei M, Beitel LK, Singh Dolt K, Karamchandani J, Stratton JA, Kunath T, Fon EA, Durcan TM. Midbrain organoids with an SNCA gene triplication model key features of synucleinopathy. Brain Commun 2021; 3:fcab223. [PMID: 34632384 PMCID: PMC8495137 DOI: 10.1093/braincomms/fcab223] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Revised: 08/06/2021] [Accepted: 08/16/2021] [Indexed: 02/05/2023] Open
Abstract
SNCA, the first gene associated with Parkinson's disease, encodes the α-synuclein protein, the predominant component within pathological inclusions termed Lewy bodies. The presence of Lewy bodies is one of the classical hallmarks found in the brain of patients with Parkinson's disease, and Lewy bodies have also been observed in patients with other synucleinopathies. However, the study of α-synuclein pathology in cells has relied largely on two-dimensional culture models, which typically lack the cellular diversity and complex spatial environment found in the brain. Here, to address this gap, we use three-dimensional midbrain organoids, differentiated from human-induced pluripotent stem cells derived from patients carrying a triplication of the SNCA gene and from CRISPR/Cas9 corrected isogenic control iPSCs. These human midbrain organoids recapitulate key features of α-synuclein pathology observed in the brains of patients with synucleinopathies. In particular, we find that SNCA triplication human midbrain organoids express elevated levels of α-synuclein and exhibit an age-dependent increase in α-synuclein aggregation, manifested by the presence of both oligomeric and phosphorylated forms of α-synuclein. These phosphorylated α-synuclein aggregates were found in both neurons and glial cells and their time-dependent accumulation correlated with a selective reduction in dopaminergic neuron numbers. Thus, human midbrain organoids from patients carrying SNCA gene multiplication can reliably model key pathological features of Parkinson's disease and provide a powerful system to study the pathogenesis of synucleinopathies.
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Affiliation(s)
- Nguyen-Vi Mohamed
- Early Drug Discovery Unit (EDDU), Department of Neurology and Neurosurgery, Montreal Neurological Institute-Hospital, McGill University, Montreal, Quebec H3A 2B4, Canada
| | - Julien Sirois
- Early Drug Discovery Unit (EDDU), Department of Neurology and Neurosurgery, Montreal Neurological Institute-Hospital, McGill University, Montreal, Quebec H3A 2B4, Canada
| | - Janani Ramamurthy
- Early Drug Discovery Unit (EDDU), Department of Neurology and Neurosurgery, Montreal Neurological Institute-Hospital, McGill University, Montreal, Quebec H3A 2B4, Canada
| | - Meghna Mathur
- Early Drug Discovery Unit (EDDU), Department of Neurology and Neurosurgery, Montreal Neurological Institute-Hospital, McGill University, Montreal, Quebec H3A 2B4, Canada
| | - Paula Lépine
- Early Drug Discovery Unit (EDDU), Department of Neurology and Neurosurgery, Montreal Neurological Institute-Hospital, McGill University, Montreal, Quebec H3A 2B4, Canada
| | - Eric Deneault
- Early Drug Discovery Unit (EDDU), Department of Neurology and Neurosurgery, Montreal Neurological Institute-Hospital, McGill University, Montreal, Quebec H3A 2B4, Canada
| | - Gilles Maussion
- Early Drug Discovery Unit (EDDU), Department of Neurology and Neurosurgery, Montreal Neurological Institute-Hospital, McGill University, Montreal, Quebec H3A 2B4, Canada
| | - Michael Nicouleau
- Early Drug Discovery Unit (EDDU), Department of Neurology and Neurosurgery, Montreal Neurological Institute-Hospital, McGill University, Montreal, Quebec H3A 2B4, Canada
| | - Carol X-Q Chen
- Early Drug Discovery Unit (EDDU), Department of Neurology and Neurosurgery, Montreal Neurological Institute-Hospital, McGill University, Montreal, Quebec H3A 2B4, Canada
| | - Narges Abdian
- Early Drug Discovery Unit (EDDU), Department of Neurology and Neurosurgery, Montreal Neurological Institute-Hospital, McGill University, Montreal, Quebec H3A 2B4, Canada
| | - Vincent Soubannier
- Early Drug Discovery Unit (EDDU), Department of Neurology and Neurosurgery, Montreal Neurological Institute-Hospital, McGill University, Montreal, Quebec H3A 2B4, Canada
| | - Eddie Cai
- Early Drug Discovery Unit (EDDU), Department of Neurology and Neurosurgery, Montreal Neurological Institute-Hospital, McGill University, Montreal, Quebec H3A 2B4, Canada
| | - Harris Nami
- Early Drug Discovery Unit (EDDU), Department of Neurology and Neurosurgery, Montreal Neurological Institute-Hospital, McGill University, Montreal, Quebec H3A 2B4, Canada
| | - Rhalena A Thomas
- Early Drug Discovery Unit (EDDU), Department of Neurology and Neurosurgery, Montreal Neurological Institute-Hospital, McGill University, Montreal, Quebec H3A 2B4, Canada
| | - Dingke Wen
- Department of Neurosurgery, West China Hospital, Sichuan University, Chengdu 610063, China
| | - Mahdieh Tabatabaei
- Early Drug Discovery Unit (EDDU), Department of Neurology and Neurosurgery, Montreal Neurological Institute-Hospital, McGill University, Montreal, Quebec H3A 2B4, Canada.,C-BIG Biorepository (C-BIG), Montreal Neurological Institute-Hospital, McGill University, Montreal, Quebec H3A 2B4, Canada
| | - Lenore K Beitel
- Early Drug Discovery Unit (EDDU), Department of Neurology and Neurosurgery, Montreal Neurological Institute-Hospital, McGill University, Montreal, Quebec H3A 2B4, Canada
| | - Karamjit Singh Dolt
- Centre for Regenerative Medicine, School of Biological Sciences, University of Edinburgh, Edinburgh EH16 4UU, UK
| | - Jason Karamchandani
- Early Drug Discovery Unit (EDDU), Department of Neurology and Neurosurgery, Montreal Neurological Institute-Hospital, McGill University, Montreal, Quebec H3A 2B4, Canada.,C-BIG Biorepository (C-BIG), Montreal Neurological Institute-Hospital, McGill University, Montreal, Quebec H3A 2B4, Canada
| | - Jo Anne Stratton
- Montreal Neurological Institute-Hospital, McGill University, Montreal, Quebec H3A 2B4, Canada
| | - Tilo Kunath
- Centre for Regenerative Medicine, School of Biological Sciences, University of Edinburgh, Edinburgh EH16 4UU, UK
| | - Edward A Fon
- Early Drug Discovery Unit (EDDU), Department of Neurology and Neurosurgery, Montreal Neurological Institute-Hospital, McGill University, Montreal, Quebec H3A 2B4, Canada
| | - Thomas M Durcan
- Early Drug Discovery Unit (EDDU), Department of Neurology and Neurosurgery, Montreal Neurological Institute-Hospital, McGill University, Montreal, Quebec H3A 2B4, Canada
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125
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Molecular chaperones and Parkinson's disease. Neurobiol Dis 2021; 160:105527. [PMID: 34626793 DOI: 10.1016/j.nbd.2021.105527] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2021] [Revised: 10/04/2021] [Accepted: 10/04/2021] [Indexed: 12/27/2022] Open
Abstract
Parkinson's disease (PD) is a neurodegenerative disease characterized by progressive death of dopaminergic neurons in the substantia nigra and the formation of Lewy bodies (LBs). Mutations in PD-related genes lead to neuronal pathogenesis through various mechanisms, with known examples including SNCA/α-synuclein (PAKR1), Parkin (PARK2), PINK1 (PARK6), DJ-1 (PARK7), and LRRK2 (PARK8). Molecular chaperones/co-chaperones are proteins that aid the folding of other proteins into a functionally active conformation. It has been demonstrated that chaperones/co-chaperones interact with PD-related proteins and regulate their function in PD. HSP70, HSP90 and small heat shock proteins can prevent neurodegeneration by regulating α-syn misfolding, oligomerization and aggregation. The function of chaperones is regulated by co-chaperones such as HSP110, HSP40, HOP, CHIP, and BAG family proteins. Parkin, PINK1 and DJ-1 are PD-related proteins which are associated with mitochondrial function. Molecular chaperones regulate mitochondrial function and protein homeostasis by interacting with these PD-related proteins. This review discusses critical molecular chaperones/co-chaperones and PD-related proteins which contribute to the pathogenesis of PD, hoping to provide new molecular targets for therapeutic interventions to thwart the disease progression instead of only bringing symptomatic relief. Moreover, appreciating the critical role of chaperones in PD can also help us screen efficient biomarkers to identify PD at an early stage.
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126
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Atieh TB, Roth J, Yang X, Hoop CL, Baum J. DJ-1 Acts as a Scavenger of α-Synuclein Oligomers and Restores Monomeric Glycated α-Synuclein. Biomolecules 2021; 11:biom11101466. [PMID: 34680099 PMCID: PMC8533443 DOI: 10.3390/biom11101466] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2021] [Revised: 09/28/2021] [Accepted: 10/01/2021] [Indexed: 12/03/2022] Open
Abstract
Glycation of α-synuclein (αSyn), as occurs with aging, has been linked to the progression of Parkinson’s disease (PD) through the promotion of advanced glycation end-products and the formation of toxic oligomers that cannot be properly cleared from neurons. DJ-1, an antioxidative protein that plays a critical role in PD pathology, has been proposed to repair glycation in proteins, yet a mechanism has not been elucidated. In this study, we integrate solution nuclear magnetic resonance (NMR) spectroscopy and liquid atomic force microscopy (AFM) techniques to characterize glycated N-terminally acetylated-αSyn (glyc-ac-αSyn) and its interaction with DJ-1. Glycation of ac-αSyn by methylglyoxal increases oligomer formation, as visualized by AFM in solution, resulting in decreased dynamics of the monomer amide backbone around the Lys residues, as measured using NMR. Upon addition of DJ-1, this NMR signature of glyc-ac-αSyn monomers reverts to a native ac-αSyn-like character. This phenomenon is reversible upon removal of DJ-1 from the solution. Using relaxation-based NMR, we have identified the binding site on DJ-1 for glycated and native ac-αSyn as the catalytic pocket and established that the oxidation state of the catalytic cysteine is imperative for binding. Based on our results, we propose a novel mechanism by which DJ-1 scavenges glyc-ac-αSyn oligomers without chemical deglycation, suppresses glyc-ac-αSyn monomer–oligomer interactions, and releases free glyc-ac-αSyn monomers in solution. The interference of DJ-1 with ac-αSyn oligomers may promote free ac-αSyn monomer in solution and suppress the propagation of toxic oligomer and fibril species. These results expand the understanding of the role of DJ-1 in PD pathology by acting as a scavenger for aggregated αSyn.
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127
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Zadali R, Hassani V, Rafiei Y, Meratan AA, Mamashli F, Nemat-Gorgani M. A study on the interaction of the amyloid fibrils of α-synuclein and hen egg white lysozyme with biological membranes. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2021; 1864:183776. [PMID: 34547253 DOI: 10.1016/j.bbamem.2021.183776] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2021] [Revised: 09/06/2021] [Accepted: 09/10/2021] [Indexed: 01/23/2023]
Abstract
Alpha-synuclein (α-syn) aggregation and mitochondrial dysfunction are considered as two of the main factors associated with Parkinson's disease (PD). In the present investigation, the effectiveness of the amyloid fibrils obtained from α-syn with those of hen egg white lysozyme (HEWL), as disease-related and-unrelated proteins, to damage rat brain and rat liver mitochondria have been investigated. This was extended by looking at SH-SY5Y human neuroblastoma cells and erythrocytes, thereby investigating the significance of structural characteristics of amyloid fibrils related to their interactions with biomembranes obtained from various sources. Results presented clearly demonstrate substantial differences in the response of tested biomembranes to toxicity induced by α-syn/HEWL amyloid fibrils, highlighting a structure-function relationship. We found that fibrillar aggregates of α-syn, but not HEWL, caused a significant increase in mitochondrial ROS, loss of membrane potential, and mitochondrial swelling, in a dose-dependent manner. Toxicity was found to be more pronounced in brain mitochondria, as compared to liver mitochondria. For SH-SY5Y cells and erythrocytes, however, both α-syn and HEWL amyloid fibrils showed the capacity to induce toxicity. Taken together, these results may suggest selective toxicity of α-syn amyloid fibrils to mitochondria mediated likely by their direct interaction with the outer mitochondrial membrane, indicating a correlation between specific structural characteristics of α-syn fibrils and an organelle strongly implicated in PD pathology.
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Affiliation(s)
- Ramin Zadali
- Department of Biological Sciences, Institute for Advanced Studies in Basic Sciences (IASBS), Zanjan 45137-66731, Iran
| | - Vahid Hassani
- Department of Biological Sciences, Institute for Advanced Studies in Basic Sciences (IASBS), Zanjan 45137-66731, Iran
| | - Yasin Rafiei
- Department of Biological Sciences, Institute for Advanced Studies in Basic Sciences (IASBS), Zanjan 45137-66731, Iran
| | - Ali Akbar Meratan
- Department of Biological Sciences, Institute for Advanced Studies in Basic Sciences (IASBS), Zanjan 45137-66731, Iran.
| | - Fatemeh Mamashli
- Institute of Biochemistry and Biophysics, University of Tehran, Tehran, Iran
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128
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Tang Q, Gao P, Arzberger T, Höllerhage M, Herms J, Höglinger G, Koeglsperger T. Alpha-Synuclein defects autophagy by impairing SNAP29-mediated autophagosome-lysosome fusion. Cell Death Dis 2021; 12:854. [PMID: 34535638 PMCID: PMC8448865 DOI: 10.1038/s41419-021-04138-0] [Citation(s) in RCA: 42] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Revised: 08/07/2021] [Accepted: 08/26/2021] [Indexed: 02/08/2023]
Abstract
Dopaminergic (DA) cell death in Parkinson's disease (PD) is associated with the gradual appearance of neuronal protein aggregates termed Lewy bodies (LBs) that are comprised of vesicular membrane structures and dysmorphic organelles in conjunction with the protein alpha-Synuclein (α-Syn). Although the exact mechanism of neuronal aggregate formation and death remains elusive, recent research suggests α-Syn-mediated alterations in the lysosomal degradation of aggregated proteins and organelles - a process termed autophagy. Here, we used a combination of molecular biology and immunochemistry to investigate the effect of α-Syn on autophagy turnover in cultured human DA neurons and in human post-mortem brain tissue. We found α-Syn overexpression to reduce autophagy turnover by compromising the fusion of autophagosomes with lysosomes, thus leading to a decrease in the formation of autolysosomes. In accord with a compensatory increase in the plasma membrane fusion of autophagosomes, α-Syn enhanced the number of extracellular vesicles (EV) and the abundance of autophagy-associated proteins in these EVs. Mechanistically, α-Syn decreased the abundance of the v-SNARE protein SNAP29, a member of the SNARE complex mediating autophagolysosome fusion. In line, SNAP29 knockdown mimicked the effect of α-Syn on autophagy whereas SNAP29 co-expression reversed the α-Syn-induced changes on autophagy turnover and EV release and ameliorated DA neuronal cell death. In accord with our results from cultured neurons, we found a stage-dependent reduction of SNAP29 in SNc DA neurons from human post-mortem brain tissue of Lewy body pathology (LBP) cases. In summary, our results thus demonstrate a previously unknown effect of α-Syn on intracellular autophagy-associated SNARE proteins and, as a consequence, a reduced autolysosome fusion. As such, our findings will therefore support the investigation of autophagy-associated pathological changes in PD.
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Affiliation(s)
- Qilin Tang
- grid.424247.30000 0004 0438 0426Department of Translational Brain Research, German Center for Neurodegenerative Diseases (DZNE), Munich, Germany ,grid.5252.00000 0004 1936 973XDepartment of Neurology, Ludwig Maximilian University, Munich, Germany
| | - Pan Gao
- grid.424247.30000 0004 0438 0426Department of Translational Brain Research, German Center for Neurodegenerative Diseases (DZNE), Munich, Germany ,grid.6936.a0000000123222966Technical University of Munich, Munich, Germany
| | - Thomas Arzberger
- grid.5252.00000 0004 1936 973XCentre of Neuropathology and Prion Research, Ludwig, Maximilian University, Munich, Germany ,grid.5252.00000 0004 1936 973XDepartment of Psychiatry and Psychotherapy, Ludwig Maximilian University, Munich, Germany
| | - Matthias Höllerhage
- grid.10423.340000 0000 9529 9877Department of Neurology, Hannover Medical School (MHH), Hannover, Germany
| | - Jochen Herms
- grid.424247.30000 0004 0438 0426Department of Translational Brain Research, German Center for Neurodegenerative Diseases (DZNE), Munich, Germany ,grid.5252.00000 0004 1936 973XCentre of Neuropathology and Prion Research, Ludwig, Maximilian University, Munich, Germany ,grid.452617.3Munich Cluster for Systems Neurology (SyNergy), Munich, Germany
| | - Günter Höglinger
- grid.10423.340000 0000 9529 9877Department of Neurology, Hannover Medical School (MHH), Hannover, Germany ,grid.424247.30000 0004 0438 0426Department of Translational Neurodegeneration, German Center for Neurodegenerative Diseases (DZNE), Munich, Germany
| | - Thomas Koeglsperger
- grid.424247.30000 0004 0438 0426Department of Translational Brain Research, German Center for Neurodegenerative Diseases (DZNE), Munich, Germany ,grid.5252.00000 0004 1936 973XDepartment of Neurology, Ludwig Maximilian University, Munich, Germany
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129
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All-or-none amyloid disassembly via chaperone-triggered fibril unzipping favors clearance of α-synuclein toxic species. Proc Natl Acad Sci U S A 2021; 118:2105548118. [PMID: 34462355 DOI: 10.1073/pnas.2105548118] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
α-synuclein aggregation is present in Parkinson's disease and other neuropathologies. Among the assemblies that populate the amyloid formation process, oligomers and short fibrils are the most cytotoxic. The human Hsc70-based disaggregase system can resolve α-synuclein fibrils, but its ability to target other toxic assemblies has not been studied. Here, we show that this chaperone system preferentially disaggregates toxic oligomers and short fibrils, while its activity against large, less toxic amyloids is severely impaired. Biochemical and kinetic characterization of the disassembly process reveals that this behavior is the result of an all-or-none abrupt solubilization of individual aggregates. High-speed atomic force microscopy explicitly shows that disassembly starts with the destabilization of the tips and rapidly progresses to completion through protofilament unzipping and depolymerization without accumulation of harmful oligomeric intermediates. Our data provide molecular insights into the selective processing of toxic amyloids, which is critical to identify potential therapeutic targets against increasingly prevalent neurodegenerative disorders.
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130
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Chen J, Zaer S, Drori P, Zamel J, Joron K, Kalisman N, Lerner E, Dokholyan NV. The structural heterogeneity of α-synuclein is governed by several distinct subpopulations with interconversion times slower than milliseconds. Structure 2021; 29:1048-1064.e6. [PMID: 34015255 PMCID: PMC8419013 DOI: 10.1016/j.str.2021.05.002] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Revised: 03/12/2021] [Accepted: 04/30/2021] [Indexed: 11/22/2022]
Abstract
α-Synuclein plays an important role in synaptic functions by interacting with synaptic vesicle membrane, while its oligomers and fibrils are associated with several neurodegenerative diseases. The specific monomer structures that promote its membrane binding and self-association remain elusive due to its transient nature as an intrinsically disordered protein. Here, we use inter-dye distance distributions from bulk time-resolved Förster resonance energy transfer as restraints in discrete molecular dynamics simulations to map the conformational space of the α-synuclein monomer. We further confirm the generated conformational ensemble in orthogonal experiments utilizing far-UV circular dichroism and cross-linking mass spectrometry. Single-molecule protein-induced fluorescence enhancement measurements show that within this conformational ensemble, some of the conformations of α-synuclein are surprisingly stable, exhibiting conformational transitions slower than milliseconds. Our comprehensive analysis of the conformational ensemble reveals essential structural properties and potential conformations that promote its various functions in membrane interaction or oligomer and fibril formation.
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Affiliation(s)
- Jiaxing Chen
- Department of Pharmacology, Penn State College of Medicine, Hershey, PA 17033, USA
| | - Sofia Zaer
- Department of Biological Chemistry, The Alexander Silberman Institute of Life Sciences, Faculty of Mathematics & Science, The Edmond J. Safra Campus, The Hebrew University of Jerusalem, Jerusalem 9190401, Israel
| | - Paz Drori
- Department of Biological Chemistry, The Alexander Silberman Institute of Life Sciences, Faculty of Mathematics & Science, The Edmond J. Safra Campus, The Hebrew University of Jerusalem, Jerusalem 9190401, Israel
| | - Joanna Zamel
- Department of Biological Chemistry, The Alexander Silberman Institute of Life Sciences, Faculty of Mathematics & Science, The Edmond J. Safra Campus, The Hebrew University of Jerusalem, Jerusalem 9190401, Israel
| | - Khalil Joron
- Department of Biological Chemistry, The Alexander Silberman Institute of Life Sciences, Faculty of Mathematics & Science, The Edmond J. Safra Campus, The Hebrew University of Jerusalem, Jerusalem 9190401, Israel
| | - Nir Kalisman
- Department of Biological Chemistry, The Alexander Silberman Institute of Life Sciences, Faculty of Mathematics & Science, The Edmond J. Safra Campus, The Hebrew University of Jerusalem, Jerusalem 9190401, Israel
| | - Eitan Lerner
- Department of Biological Chemistry, The Alexander Silberman Institute of Life Sciences, Faculty of Mathematics & Science, The Edmond J. Safra Campus, The Hebrew University of Jerusalem, Jerusalem 9190401, Israel; The Center for Nanoscience and Nanotechnology, The Hebrew University of Jerusalem, Jerusalem 9190401, Israel.
| | - Nikolay V Dokholyan
- Department of Pharmacology, Penn State College of Medicine, Hershey, PA 17033, USA; Department of Biochemistry & Molecular Biology, Penn State College of Medicine, Hershey, PA 17033, USA; Departments of Chemistry and Biomedical Engineering, Pennsylvania State University, University Park, PA 16802, USA.
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131
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Albert K, Raymundo DP, Panhelainen A, Eesmaa A, Shvachiy L, Araújo GR, Chmielarz P, Yan X, Singh A, Cordeiro Y, Palhano FL, Foguel D, Luk KC, Domanskyi A, Voutilainen MH, Huttunen HJ, Outeiro TF, Saarma M, Almeida MS, Airavaara M. Cerebral dopamine neurotrophic factor reduces α-synuclein aggregation and propagation and alleviates behavioral alterations in vivo. Mol Ther 2021; 29:2821-2840. [PMID: 33940158 PMCID: PMC8417450 DOI: 10.1016/j.ymthe.2021.04.035] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Revised: 02/11/2021] [Accepted: 04/27/2021] [Indexed: 01/16/2023] Open
Abstract
A molecular hallmark in Parkinson's disease (PD) pathogenesis are α-synuclein aggregates. Cerebral dopamine neurotrophic factor (CDNF) is an atypical growth factor that is mostly resident in the endoplasmic reticulum but exerts its effects both intracellularly and extracellularly. One of the beneficial effects of CDNF can be protecting neurons from the toxic effects of α-synuclein. Here, we investigated the effects of CDNF on α-synuclein aggregation in vitro and in vivo. We found that CDNF directly interacts with α-synuclein with a KD = 23 ± 6 nM and reduces its auto-association. Using nuclear magnetic resonance (NMR) spectroscopy, we identified interaction sites on the CDNF protein. Remarkably, CDNF reduces the neuronal internalization of α-synuclein fibrils and induces the formation of insoluble phosphorylated α-synuclein inclusions. Intra-striatal CDNF administration alleviates motor deficits in rodents challenged with α-synuclein fibrils, though it did not reduce the number of phosphorylated α-synuclein inclusions in the substantia nigra. CDNF's beneficial effects on rodent behavior appear not to be related to the number of inclusions formed in the current context, and further study of its effects on the aggregation mechanism in vivo are needed. Nonetheless, the interaction of CDNF with α-synuclein, modifying its aggregation, spreading, and associated behavioral alterations, provides novel insights into the potential of CDNF as a therapeutic strategy in PD and other synucleinopathies.
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Affiliation(s)
- Katrina Albert
- Institute of Biotechnology, HiLIFE, University of Helsinki, 00014 Helsinki, Finland
| | - Diana P Raymundo
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21.941-902, Brazil; Department of Experimental Neurodegeneration, Center for Biostructural Imaging of Neurodegeneration, University Medical Center Göttingen, 37073 Göttingen, Germany; Protein Advanced Biochemistry, CENABIO, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21.941-902, Brazil
| | - Anne Panhelainen
- Institute of Biotechnology, HiLIFE, University of Helsinki, 00014 Helsinki, Finland; Faculty of Pharmacy, University of Helsinki, Helsinki, Finland
| | - Ave Eesmaa
- Institute of Biotechnology, HiLIFE, University of Helsinki, 00014 Helsinki, Finland
| | - Liana Shvachiy
- Department of Experimental Neurodegeneration, Center for Biostructural Imaging of Neurodegeneration, University Medical Center Göttingen, 37073 Göttingen, Germany; Centro Cardiovascular da Universidade de Lisboa, Faculdade de Medicina, Universidade de Lisboa, Av Prof Egas Moniz, 1649-028 Lisbon, Portugal
| | - Gabriela R Araújo
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21.941-902, Brazil; Protein Advanced Biochemistry, CENABIO, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21.941-902, Brazil
| | - Piotr Chmielarz
- Institute of Biotechnology, HiLIFE, University of Helsinki, 00014 Helsinki, Finland; Department of Brain Biochemistry, Maj Institute of Pharmacology, Polish Academy of Sciences, Krakow 31-343, Poland
| | - Xu Yan
- Neuroscience Center, HiLIFE, University of Helsinki, 00014 Helsinki, Finland
| | - Aastha Singh
- Institute of Biotechnology, HiLIFE, University of Helsinki, 00014 Helsinki, Finland
| | - Yraima Cordeiro
- Faculdade de Farmácia, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21.941-902, Brazil
| | - Fernando L Palhano
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21.941-902, Brazil
| | - Debora Foguel
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21.941-902, Brazil
| | - Kelvin C Luk
- Center for Neurodegenerative Disease Research, Department of Pathology and Laboratory Medicine, University of Pennsylvania, Perelman School of Medicine, Philadelphia, PA 19104, USA
| | - Andrii Domanskyi
- Institute of Biotechnology, HiLIFE, University of Helsinki, 00014 Helsinki, Finland
| | - Merja H Voutilainen
- Institute of Biotechnology, HiLIFE, University of Helsinki, 00014 Helsinki, Finland; Faculty of Pharmacy, University of Helsinki, Helsinki, Finland
| | - Henri J Huttunen
- Neuroscience Center, HiLIFE, University of Helsinki, 00014 Helsinki, Finland; Herantis Pharma Plc, 20520 Espoo, Finland
| | - Tiago F Outeiro
- Department of Experimental Neurodegeneration, Center for Biostructural Imaging of Neurodegeneration, University Medical Center Göttingen, 37073 Göttingen, Germany; Max Planck Institute for Experimental Medicine, 37075 Göttingen, Germany; Institute of Neuroscience, The Medical School, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
| | - Mart Saarma
- Institute of Biotechnology, HiLIFE, University of Helsinki, 00014 Helsinki, Finland
| | - Marcius S Almeida
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21.941-902, Brazil; Protein Advanced Biochemistry, CENABIO, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21.941-902, Brazil.
| | - Mikko Airavaara
- Institute of Biotechnology, HiLIFE, University of Helsinki, 00014 Helsinki, Finland; Neuroscience Center, HiLIFE, University of Helsinki, 00014 Helsinki, Finland; Faculty of Pharmacy, University of Helsinki, Helsinki, Finland.
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132
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Alpha-Synuclein PET Tracer Development-An Overview about Current Efforts. Pharmaceuticals (Basel) 2021; 14:ph14090847. [PMID: 34577548 PMCID: PMC8466155 DOI: 10.3390/ph14090847] [Citation(s) in RCA: 52] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2021] [Revised: 08/16/2021] [Accepted: 08/17/2021] [Indexed: 12/18/2022] Open
Abstract
Neurodegenerative diseases such as Parkinson’s disease (PD) are manifested by inclusion bodies of alpha-synuclein (α-syn) also called α-synucleinopathies. Detection of these inclusions is thus far only possible by histological examination of postmortem brain tissue. The possibility of non-invasively detecting α-syn will therefore provide valuable insights into the disease progression of α-synucleinopathies. In particular, α-syn imaging can quantify changes in monomeric, oligomeric, and fibrillic α-syn over time and improve early diagnosis of various α-synucleinopathies or monitor treatment progress. Positron emission tomography (PET) is a non-invasive in vivo imaging technique that can quantify target expression and drug occupancies when a suitable tracer exists. As such, novel α-syn PET tracers are highly sought after. The development of an α-syn PET tracer faces several challenges. For example, the low abundance of α-syn within the brain necessitates the development of a high-affinity ligand. Moreover, α-syn depositions are, in contrast to amyloid proteins, predominantly localized intracellularly, limiting their accessibility. Furthermore, another challenge is the ligand selectivity over structurally similar amyloids such as amyloid-beta or tau, which are often co-localized with α-syn pathology. The lack of a defined crystal structure of α-syn has also hindered rational drug and tracer design efforts. Our objective for this review is to provide a comprehensive overview of current efforts in the development of selective α-syn PET tracers.
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Kayed R, Dettmer U, Lesné SE. Soluble endogenous oligomeric α-synuclein species in neurodegenerative diseases: Expression, spreading, and cross-talk. JOURNAL OF PARKINSON'S DISEASE 2021; 10:791-818. [PMID: 32508330 PMCID: PMC7458533 DOI: 10.3233/jpd-201965] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
There is growing recognition in the field of neurodegenerative diseases that mixed proteinopathies are occurring at greater frequency than originally thought. This is particularly true for three amyloid proteins defining most of these neurological disorders, amyloid-beta (Aβ), tau, and alpha-synuclein (αSyn). The co-existence and often co-localization of aggregated forms of these proteins has led to the emergence of concepts positing molecular interactions and cross-seeding between Aβ, tau, and αSyn aggregates. Amongst this trio, αSyn has received particular attention in this context during recent years due to its ability to modulate Aβ and tau aggregation in vivo, to interact at a molecular level with Aβ and tau in vivo and to cross-seed tau in mice. Here we provide a comprehensive, critical, and accessible review about the expression, role and nature of endogenous soluble αSyn oligomers because of recent developments in the understanding of αSyn multimerization, misfolding, aggregation, cross-talk, spreading and cross-seeding in neurodegenerative disorders, including Parkinson's disease, dementia with Lewy bodies, multiple system atrophy, Alzheimer's disease, and Huntington's disease. We will also discuss our current understanding about the relative toxicity of endogenous αSyn oligomers in vivo and in vitro, and introduce potential opportunities to counter their deleterious effects.
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Affiliation(s)
- Rakez Kayed
- Departments of Neurology & Neuroscience & Cell Biology & Anatomy, University of Texas Medical Branch Galveston, Galveston, TX, USA,George and Cynthia Mitchell Center for Neurodegenerative Diseases, University of Texas Medical Branch Galveston, Galveston, TX, USA
| | - Ulf Dettmer
- Department of Neurology, Harvard Medical School, Boston, MA, USA,Ann Romney Center for Neurologic Diseases, Harvard Medical School, Boston, MA, USA
| | - Sylvain E. Lesné
- Department of Neuroscience, University of Minnesota, Minneapolis, MN, USA,Institute of Translational Neuroscience, University of Minnesota, Minneapolis, MN, USA,Correspondence to: Sylvain E. Lesné, PhD, University of Minnesota, Wallin Medical Biosciences Building (Room 4-114), 2101 Sixth Street SE, CDC 2641, Minneapolis, MN 55414, USA. Tel.: +1 612 626 8341; E-mail: ; Website: https://lesnelab.org
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134
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Jan A, Gonçalves NP, Vaegter CB, Jensen PH, Ferreira N. The Prion-Like Spreading of Alpha-Synuclein in Parkinson's Disease: Update on Models and Hypotheses. Int J Mol Sci 2021; 22:8338. [PMID: 34361100 PMCID: PMC8347623 DOI: 10.3390/ijms22158338] [Citation(s) in RCA: 43] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Revised: 07/29/2021] [Accepted: 07/30/2021] [Indexed: 12/11/2022] Open
Abstract
The pathological aggregation of the presynaptic protein α-synuclein (α-syn) and propagation through synaptically coupled neuroanatomical tracts is increasingly thought to underlie the pathophysiological progression of Parkinson's disease (PD) and related synucleinopathies. Although the precise molecular mechanisms responsible for the spreading of pathological α-syn accumulation in the CNS are not fully understood, growing evidence suggests that de novo α-syn misfolding and/or neuronal internalization of aggregated α-syn facilitates conformational templating of endogenous α-syn monomers in a mechanism reminiscent of prions. A refined understanding of the biochemical and cellular factors mediating the pathological neuron-to-neuron propagation of misfolded α-syn will potentially elucidate the etiology of PD and unravel novel targets for therapeutic intervention. Here, we discuss recent developments on the hypothesis regarding trans-synaptic propagation of α-syn pathology in the context of neuronal vulnerability and highlight the potential utility of novel experimental models of synucleinopathies.
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Affiliation(s)
- Asad Jan
- Danish Research Institute of Translational Neuroscience (DANDRITE), Nordic EMBL Partnership for Molecular Medicine, Department of Biomedicine, Aarhus University, 8000 Aarhus, Denmark; (N.P.G.); (C.B.V.); (P.H.J.)
| | - Nádia Pereira Gonçalves
- Danish Research Institute of Translational Neuroscience (DANDRITE), Nordic EMBL Partnership for Molecular Medicine, Department of Biomedicine, Aarhus University, 8000 Aarhus, Denmark; (N.P.G.); (C.B.V.); (P.H.J.)
- International Diabetic Neuropathy Consortium (IDNC), Aarhus University Hospital, 8200 Aarhus, Denmark
| | - Christian Bjerggaard Vaegter
- Danish Research Institute of Translational Neuroscience (DANDRITE), Nordic EMBL Partnership for Molecular Medicine, Department of Biomedicine, Aarhus University, 8000 Aarhus, Denmark; (N.P.G.); (C.B.V.); (P.H.J.)
- International Diabetic Neuropathy Consortium (IDNC), Aarhus University Hospital, 8200 Aarhus, Denmark
| | - Poul Henning Jensen
- Danish Research Institute of Translational Neuroscience (DANDRITE), Nordic EMBL Partnership for Molecular Medicine, Department of Biomedicine, Aarhus University, 8000 Aarhus, Denmark; (N.P.G.); (C.B.V.); (P.H.J.)
| | - Nelson Ferreira
- Danish Research Institute of Translational Neuroscience (DANDRITE), Nordic EMBL Partnership for Molecular Medicine, Department of Biomedicine, Aarhus University, 8000 Aarhus, Denmark; (N.P.G.); (C.B.V.); (P.H.J.)
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135
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Poewe W, Volc D, Seppi K, Medori R, Lührs P, Kutzelnigg A, Djamshidian A, Thun-Hohenstein C, Meissner WG, Rascol O, Schneeberger A, Staffler G, Poewe W, Seppi K, Djamshidian A, deMarzi R, Heim B, Mangesius S, Stolz R, Wachowicz K, Volc D, Thun-Hohenstein C, Riha C, Schneeberger A, Bürger V, Galabova G. Safety and Tolerability of Active Immunotherapy Targeting α-Synuclein with PD03A in Patients with Early Parkinson's Disease: A Randomized, Placebo-Controlled, Phase 1 Study. JOURNAL OF PARKINSONS DISEASE 2021; 11:1079-1089. [PMID: 34092654 PMCID: PMC8461711 DOI: 10.3233/jpd-212594] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Background: Immunotherapies targeting α-synuclein aim to limit its extracellular spread in the brain and prevent progression of pathology in Parkinson’s disease (PD). PD03A is a specific active immunotherapy (SAIT) involving immunization with a short peptide formulation. Objective: This phase 1 study characterized the safety and tolerability of PD03A in patients with early PD. A key secondary objective was to evaluate immunological activity following immunization. Methods: This was a phase 1 study of two different doses of PD03A versus placebo in PD patients. Patients were randomized (1:1:1) to receive four priming plus one booster vaccination of PD03A 15μg, PD03A 75μg or placebo and were followed for 52 weeks. Results: Overall, 36 patients were randomized, of which 35 received five immunizations and completed the study. All patients experienced at least one adverse event. Transient local injection site reactions affected all but two patients; otherwise most AEs were considered unrelated to study treatment. A substantial IgG antibody response against PD03 was observed with a maximum titer achieved at Week-12. Differences in titers between both active groups versus placebo were statistically significant from the second immunization at Week-8 until Week-52. Conclusion: The safety profile and positive antibody response of PD03A supports the further development of active immunotherapeutic approaches for the treatment of PD.
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Affiliation(s)
- Werner Poewe
- Department of Neurology, Medical University Innsbruck, Innsbruck, Austria
| | - Dieter Volc
- PROSENEX Study Center at Privatklinik Confraternitaet, Vienna, Austria
| | - Klaus Seppi
- Department of Neurology, Medical University Innsbruck, Innsbruck, Austria
| | | | | | | | - Atbin Djamshidian
- Department of Neurology, Medical University Innsbruck, Innsbruck, Austria
| | | | - Wassilios G Meissner
- Service de Neurologie, CRMR Atrophie Multisystématisée, CHU Bordeaux and Université Bordeaux, CNRS, IMN, UMR 5293, F-33000 Bordeaux, France
| | - Olivier Rascol
- Toulouse Parkinson Expert Center, Departments of Neurosciences and Clinical Pharmacology, Centre d'Investigation Clinique de Toulouse CIC1436, NS-Park/FCRIN Network, and NeuroToul COEN Center, University Hospital of Toulouse, INSERM, University of Toulouse, Toulouse, France
| | | | | | | | | | - Werner Poewe
- Department of Neurology, Medical University Innsbruck, Innsbruck, Austria
| | - Klaus Seppi
- Department of Neurology, Medical University Innsbruck, Innsbruck, Austria
| | - Atbin Djamshidian
- Department of Neurology, Medical University Innsbruck, Innsbruck, Austria
| | - Roberto deMarzi
- Department of Neurology, Medical University Innsbruck, Innsbruck, Austria
| | - Beatrice Heim
- Department of Neurology, Medical University Innsbruck, Innsbruck, Austria
| | | | - Raphaela Stolz
- Department of Neurology, Medical University Innsbruck, Innsbruck, Austria
| | | | - Dieter Volc
- PROSENEX Study Center at Privatklinik Confraternitaet, Vienna, Austria
| | | | - Constanze Riha
- PROSENEX Study Center at Privatklinik Confraternitaet, Vienna, Austria
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136
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Zielinski M, Röder C, Schröder GF. Challenges in sample preparation and structure determination of amyloids by cryo-EM. J Biol Chem 2021; 297:100938. [PMID: 34224730 PMCID: PMC8335658 DOI: 10.1016/j.jbc.2021.100938] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Revised: 06/28/2021] [Accepted: 07/01/2021] [Indexed: 01/12/2023] Open
Abstract
Amyloids share a common architecture but play disparate biological roles in processes ranging from bacterial defense mechanisms to protein misfolding diseases. Their structures are highly polymorphic, which makes them difficult to study by X-ray diffraction or NMR spectroscopy. Our understanding of amyloid structures is due in large part to recent advances in the field of cryo-EM, which allows for determining the polymorphs separately. In this review, we highlight the main stepping stones leading to the substantial number of high-resolution amyloid fibril structures known today as well as recent developments regarding automation and software in cryo-EM. We discuss that sample preparation should move closer to physiological conditions to understand how amyloid aggregation and disease are linked. We further highlight new approaches to address heterogeneity and polymorphism of amyloid fibrils in EM image processing and give an outlook to the upcoming challenges in researching the structural biology of amyloids.
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Affiliation(s)
- Mara Zielinski
- Institute of Biological Information Processing, Structural Biochemistry (IBI-7) and JuStruct, Jülich Center for Structural Biology, Forschungszentrum Jülich, Jülich, Germany
| | - Christine Röder
- Institute of Biological Information Processing, Structural Biochemistry (IBI-7) and JuStruct, Jülich Center for Structural Biology, Forschungszentrum Jülich, Jülich, Germany; Institut für Physikalische Biologie, Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany
| | - Gunnar F Schröder
- Institute of Biological Information Processing, Structural Biochemistry (IBI-7) and JuStruct, Jülich Center for Structural Biology, Forschungszentrum Jülich, Jülich, Germany; Physics Department, Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany.
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137
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Chien HM, Lee CC, Huang JJT. The Different Faces of the TDP-43 Low-Complexity Domain: The Formation of Liquid Droplets and Amyloid Fibrils. Int J Mol Sci 2021; 22:ijms22158213. [PMID: 34360978 PMCID: PMC8348237 DOI: 10.3390/ijms22158213] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Revised: 07/22/2021] [Accepted: 07/27/2021] [Indexed: 12/17/2022] Open
Abstract
Transactive response DNA-binding protein 43 (TDP-43) is a nucleic acid-binding protein that is involved in transcription and translation regulation, non-coding RNA processing, and stress granule assembly. Aside from its multiple functions, it is also known as the signature protein in the hallmark inclusions of amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD) patients. TDP-43 is built of four domains, but its low-complexity domain (LCD) has become an intense research focus that brings to light its possible role in TDP-43 functions and involvement in the pathogenesis of these neurodegenerative diseases. Recent endeavors have further uncovered the distinct biophysical properties of TDP-43 under various circumstances. In this review, we summarize the multiple structural and biochemical properties of LCD in either promoting the liquid droplets or inducing fibrillar aggregates. We also revisit the roles of the LCD in paraspeckles, stress granules, and cytoplasmic inclusions to date.
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Affiliation(s)
- Hung-Ming Chien
- Institute of Chemistry, Academia Sinica, Nangang, Taipei City 115, Taiwan; (H.-M.C.); (C.-C.L.)
- Department of Chemistry, National Taiwan University, Taipei City 115, Taiwan
- Chemical Biology and Molecular Biophysics Program, Taiwan International Graduate Program, Academia Sinica and National Taiwan University, Taipei City 115, Taiwan
| | - Chi-Chang Lee
- Institute of Chemistry, Academia Sinica, Nangang, Taipei City 115, Taiwan; (H.-M.C.); (C.-C.L.)
| | - Joseph Jen-Tse Huang
- Institute of Chemistry, Academia Sinica, Nangang, Taipei City 115, Taiwan; (H.-M.C.); (C.-C.L.)
- Department of Applied Chemistry, National Chiayi University, Chiayi City 600, Taiwan
- Neuroscience Program of Academia Sinica, Academia Sinica, Taipei City 115, Taiwan
- Correspondence: ; Tel.: +886-2-5572-8652
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138
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Walther R, Monge P, Pedersen AB, Benderoth A, Pedersen JN, Farzadfard A, Mandrup OA, Howard KA, Otzen DE, Zelikin AN. Per-glycosylation of the Surface-Accessible Lysines: One-Pot Aqueous Route to Stabilized Proteins with Native Activity. Chembiochem 2021; 22:2478-2485. [PMID: 33998129 DOI: 10.1002/cbic.202100228] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2021] [Indexed: 11/11/2022]
Abstract
Chemical glycosylation of proteins is a powerful tool applied widely in biomedicine and biotechnology. However, it is a challenging undertaking and typically relies on recombinant proteins and site-specific conjugations. The scope and utility of this nature-inspired methodology would be broadened tremendously by the advent of facile, scalable techniques in glycosylation, which are currently missing. In this work, we investigated a one-pot aqueous protocol to achieve indiscriminate, surface-wide glycosylation of the surface accessible amines (lysines and/or N-terminus). We reveal that this approach afforded minimal if any change in the protein activity and recognition events in biochemical and cell culture assays, but at the same time provided a significant benefit of stabilizing proteins against aggregation and fibrillation - as demonstrated on serum proteins (albumins and immunoglobulin G, IgG), an enzyme (uricase), and proteins involved in neurodegenerative disease (α-synuclein) and diabetes (insulin). Most importantly, this highly advantageous result was achieved via a one-pot aqueous protocol performed on native proteins, bypassing the use of complex chemical methodologies and recombinant proteins.
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Affiliation(s)
- Raoul Walther
- Department of Chemistry, Aarhus University, Aarhus, 8000, Denmark
| | - Pere Monge
- Department of Chemistry, Aarhus University, Aarhus, 8000, Denmark
| | | | - Anja Benderoth
- Department of Chemistry, Aarhus University, Aarhus, 8000, Denmark
| | | | - Azad Farzadfard
- Interdisciplinary Nanoscience Centre (iNANO), Aarhus University, Aarhus, 8000, Denmark
| | - Ole A Mandrup
- Interdisciplinary Nanoscience Centre (iNANO), Aarhus University, Aarhus, 8000, Denmark
| | - Kenneth A Howard
- Interdisciplinary Nanoscience Centre (iNANO), Aarhus University, Aarhus, 8000, Denmark
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus, 8000, Denmark
| | - Daniel E Otzen
- Interdisciplinary Nanoscience Centre (iNANO), Aarhus University, Aarhus, 8000, Denmark
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus, 8000, Denmark
| | - Alexander N Zelikin
- Department of Chemistry, Aarhus University, Aarhus, 8000, Denmark
- Interdisciplinary Nanoscience Centre (iNANO), Aarhus University, Aarhus, 8000, Denmark
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139
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Kharkov BB, Podkorytov IS, Bondarev SA, Belousov MV, Salikov VA, Zhouravleva GA, Skrynnikov NR. The Role of Rotational Motion in Diffusion NMR Experiments on Supramolecular Assemblies: Application to Sup35NM Fibrils. Angew Chem Int Ed Engl 2021; 60:15445-15451. [PMID: 33891789 DOI: 10.1002/anie.202102408] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Revised: 04/19/2021] [Indexed: 11/08/2022]
Abstract
Pulsed-field gradient (PFG) NMR is an important tool for characterization of biomolecules and supramolecular assemblies. However, for micrometer-sized objects, such as amyloid fibrils, these experiments become difficult to interpret because in addition to translational diffusion they are also sensitive to rotational diffusion. We have constructed a mathematical theory describing the outcome of PFG NMR experiments on rod-like fibrils. To test its validity, we have studied the fibrils formed by Sup35NM segment of the prion protein Sup35. The interpretation of the PFG NMR data in this system is fully consistent with the evidence from electron microscopy. Contrary to some previously expressed views, the signals originating from disordered regions in the fibrils can be readily differentiated from the similar signals representing small soluble species (e.g. proteolytic fragments). This paves the way for diffusion-sorted NMR experiments on complex amyloidogenic samples.
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Affiliation(s)
- Boris B Kharkov
- Laboratory of Biomolecular NMR, St. Petersburg State University, 199034, St. Petersburg, Russia
| | - Ivan S Podkorytov
- Laboratory of Biomolecular NMR, St. Petersburg State University, 199034, St. Petersburg, Russia
| | - Stanislav A Bondarev
- Department of Genetics and Biotechnology, St. Petersburg State University, 199034, St. Petersburg, Russia
| | - Mikhail V Belousov
- Department of Genetics and Biotechnology, St. Petersburg State University, 199034, St. Petersburg, Russia.,Laboratory for Proteomics of Supra-Organismal Systems, All-Russia Research Institute for Agricultural Microbiology (ARRIAM), 196608, St. Petersburg, Russia
| | - Vladislav A Salikov
- Laboratory of Biomolecular NMR, St. Petersburg State University, 199034, St. Petersburg, Russia
| | - Galina A Zhouravleva
- Department of Genetics and Biotechnology, St. Petersburg State University, 199034, St. Petersburg, Russia
| | - Nikolai R Skrynnikov
- Laboratory of Biomolecular NMR, St. Petersburg State University, 199034, St. Petersburg, Russia.,Department of Chemistry, Purdue University, West Lafayette, IN, 47907, USA
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140
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Kharkov BB, Podkorytov IS, Bondarev SA, Belousov MV, Salikov VA, Zhouravleva GA, Skrynnikov NR. The Role of Rotational Motion in Diffusion NMR Experiments on Supramolecular Assemblies: Application to Sup35NM Fibrils. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202102408] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Boris B. Kharkov
- Laboratory of Biomolecular NMR St. Petersburg State University 199034 St. Petersburg Russia
| | - Ivan S. Podkorytov
- Laboratory of Biomolecular NMR St. Petersburg State University 199034 St. Petersburg Russia
| | - Stanislav A. Bondarev
- Department of Genetics and Biotechnology St. Petersburg State University 199034 St. Petersburg Russia
| | - Mikhail V. Belousov
- Department of Genetics and Biotechnology St. Petersburg State University 199034 St. Petersburg Russia
- Laboratory for Proteomics of Supra-Organismal Systems All-Russia Research Institute for Agricultural Microbiology (ARRIAM) 196608 St. Petersburg Russia
| | - Vladislav A. Salikov
- Laboratory of Biomolecular NMR St. Petersburg State University 199034 St. Petersburg Russia
| | - Galina A. Zhouravleva
- Department of Genetics and Biotechnology St. Petersburg State University 199034 St. Petersburg Russia
| | - Nikolai R. Skrynnikov
- Laboratory of Biomolecular NMR St. Petersburg State University 199034 St. Petersburg Russia
- Department of Chemistry Purdue University West Lafayette IN 47907 USA
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141
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Tanudjojo B, Shaikh SS, Fenyi A, Bousset L, Agarwal D, Marsh J, Zois C, Heman-Ackah S, Fischer R, Sims D, Melki R, Tofaris GK. Phenotypic manifestation of α-synuclein strains derived from Parkinson's disease and multiple system atrophy in human dopaminergic neurons. Nat Commun 2021; 12:3817. [PMID: 34155194 PMCID: PMC8217249 DOI: 10.1038/s41467-021-23682-z] [Citation(s) in RCA: 40] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2020] [Accepted: 05/11/2021] [Indexed: 02/05/2023] Open
Abstract
α-Synuclein is critical in the pathogenesis of Parkinson's disease and related disorders, yet it remains unclear how its aggregation causes degeneration of human dopaminergic neurons. In this study, we induced α-synuclein aggregation in human iPSC-derived dopaminergic neurons using fibrils generated de novo or amplified in the presence of brain homogenates from Parkinson's disease or multiple system atrophy. Increased α-synuclein monomer levels promote seeded aggregation in a dose and time-dependent manner, which is associated with a further increase in α-synuclein gene expression. Progressive neuronal death is observed with brain-amplified fibrils and reversed by reduction of intraneuronal α-synuclein abundance. We identified 56 proteins differentially interacting with aggregates triggered by brain-amplified fibrils, including evasion of Parkinson's disease-associated deglycase DJ-1. Knockout of DJ-1 in iPSC-derived dopaminergic neurons enhance fibril-induced aggregation and neuronal death. Taken together, our results show that the toxicity of α-synuclein strains depends on aggregate burden, which is determined by monomer levels and conformation which dictates differential interactomes. Our study demonstrates how Parkinson's disease-associated genes influence the phenotypic manifestation of strains in human neurons.
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Affiliation(s)
- Benedict Tanudjojo
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK
| | - Samiha S Shaikh
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK
| | - Alexis Fenyi
- CEA, Institut François Jacob (MIRCen) and CNRS, Laboratory of Neurodegenerative Diseases, Fontenay-aux-Roses, France
| | - Luc Bousset
- CEA, Institut François Jacob (MIRCen) and CNRS, Laboratory of Neurodegenerative Diseases, Fontenay-aux-Roses, France
| | - Devika Agarwal
- MRC Centre for Computational Biology, University of Oxford, Oxford, UK
- MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK
| | - Jade Marsh
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK
| | - Christos Zois
- MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK
| | - Sabrina Heman-Ackah
- Department of Neurosurgery, University of Pennsylvania, Philadelphia, PA, USA
| | - Roman Fischer
- Target Discovery Institute, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - David Sims
- MRC Centre for Computational Biology, University of Oxford, Oxford, UK
- MRC Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK
| | - Ronald Melki
- CEA, Institut François Jacob (MIRCen) and CNRS, Laboratory of Neurodegenerative Diseases, Fontenay-aux-Roses, France
| | - George K Tofaris
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK.
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142
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Bang S, Lee S, Choi N, Kim HN. Emerging Brain-Pathophysiology-Mimetic Platforms for Studying Neurodegenerative Diseases: Brain Organoids and Brains-on-a-Chip. Adv Healthc Mater 2021; 10:e2002119. [PMID: 34028201 DOI: 10.1002/adhm.202002119] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2020] [Revised: 03/25/2021] [Indexed: 12/13/2022]
Abstract
Neurodegenerative diseases are a group of disorders characterized by progressive degeneration of the structural and functional integrity of the central and peripheral nervous systems. Millions of people suffer from degenerative brain diseases worldwide, and the mortality continues to increase every year, causing a growing demand for knowledge of the underlying mechanisms and development of therapeutic targets. Conventional 2D-based cell culture platforms and animal models cannot fully recapitulate the pathophysiology, and this has limited the capability for estimating drug efficacy. Recently, engineered platforms, including brain organoids and brain-on-a-chip, have emerged. They mimic the physiology of brain tissue and reflect the fundamental pathophysiological signatures of neurodegenerative diseases, such as the accumulation of neurotoxic proteins, structural abnormalities, and functional loss. In this paper, recent advances in brain-mimetic platforms and their potential for modeling features of neurodegenerative diseases in vitro are reviewed. The development of a physiologically relevant model should help overcome unresolved neurodegenerative diseases.
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Affiliation(s)
- Seokyoung Bang
- Brain Science Institute Korea Institute of Science and Technology (KIST) Seoul 02792 Republic of Korea
| | - Songhyun Lee
- Department of Medical Engineering Yonsei University College of Medicine Seoul 03722 Republic of Korea
| | - Nakwon Choi
- Brain Science Institute Korea Institute of Science and Technology (KIST) Seoul 02792 Republic of Korea
- KU‐KIST Graduate School of Converging Science and Technology Korea University Seoul 02841 Republic of Korea
| | - Hong Nam Kim
- Brain Science Institute Korea Institute of Science and Technology (KIST) Seoul 02792 Republic of Korea
- Division of Bio‐Medical Science & Technology KIST School Korea University of Science and Technology (UST) Seoul 02792 Republic of Korea
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143
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Luise A, De Cecco E, Ponzini E, Sollazzo M, Mauri P, Sobott F, Legname G, Grandori R, Santambrogio C. Profiling Dopamine-Induced Oxidized Proteoforms of β-synuclein by Top-Down Mass Spectrometry. Antioxidants (Basel) 2021; 10:antiox10060893. [PMID: 34206096 PMCID: PMC8226665 DOI: 10.3390/antiox10060893] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Revised: 05/19/2021] [Accepted: 05/28/2021] [Indexed: 01/16/2023] Open
Abstract
The formation of multiple proteoforms by post-translational modifications (PTMs) enables a single protein to acquire distinct functional roles in its biological context. Oxidation of methionine residues (Met) is a common PTM, involved in physiological (e.g., signaling) and pathological (e.g., oxidative stress) states. This PTM typically maps at multiple protein sites, generating a heterogeneous population of proteoforms with specific biophysical and biochemical properties. The identification and quantitation of the variety of oxidized proteoforms originated under a given condition is required to assess the exact molecular nature of the species responsible for the process under investigation. In this work, the binding and oxidation of human β-synuclein (BS) by dopamine (DA) has been explored. Native mass spectrometry (MS) has been employed to analyze the interaction of BS with DA. In a second step, top-down fragmentation of the intact protein from denaturing conditions has been performed to identify and quantify the distinct proteoforms generated by DA-induced oxidation. The analysis of isobaric proteoforms is approached by a combination of electron-transfer dissociation (ETD) at each extent of modification, quantitation of methionine-containing fragments and combinatorial analysis of the fragmentation products by multiple linear regression. This procedure represents a promising approach to systematic assessment of proteoforms variety and their relative abundance. The method can be adapted, in principle, to any protein containing any number of methionine residues, allowing for a full structural characterization of the protein oxidation states.
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Affiliation(s)
- Arianna Luise
- Department of Biotechnology and Biosciences, University of Milano-Bicocca, 20126 Milan, Italy
| | - Elena De Cecco
- Department of Neuroscience, Scuola Internazionale Superiore di Studi Avanzati (SISSA), 34136 Trieste, Italy
- ELETTRA-Sincrotrone Trieste S.C.p.A, Basovizza, 34149 Trieste, Italy
| | - Erika Ponzini
- Department of Materials Science, University of Milano-Bicocca, 20125 Milan, Italy
| | - Martina Sollazzo
- Department of Neuroscience, Scuola Internazionale Superiore di Studi Avanzati (SISSA), 34136 Trieste, Italy
- ELETTRA-Sincrotrone Trieste S.C.p.A, Basovizza, 34149 Trieste, Italy
| | - PierLuigi Mauri
- Institute of Biomedical Technologies, National Research Council of Italy, Segrate, 20090 Milan, Italy
| | - Frank Sobott
- School of Molecular and Cellular Biology and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds LS2 9JT, UK
| | - Giuseppe Legname
- Department of Neuroscience, Scuola Internazionale Superiore di Studi Avanzati (SISSA), 34136 Trieste, Italy
- ELETTRA-Sincrotrone Trieste S.C.p.A, Basovizza, 34149 Trieste, Italy
| | - Rita Grandori
- Department of Biotechnology and Biosciences, University of Milano-Bicocca, 20126 Milan, Italy
| | - Carlo Santambrogio
- Department of Biotechnology and Biosciences, University of Milano-Bicocca, 20126 Milan, Italy
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144
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Otzen DE, Dueholm MS, Najarzadeh Z, Knowles TPJ, Ruggeri FS. In situ Sub-Cellular Identification of Functional Amyloids in Bacteria and Archaea by Infrared Nanospectroscopy. SMALL METHODS 2021; 5:e2001002. [PMID: 34927901 DOI: 10.1002/smtd.202001002] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2020] [Revised: 03/16/2021] [Indexed: 06/14/2023]
Abstract
Formation of amyloid structures is originally linked to human disease. However, amyloid materials are found extensively in the animal and bacterial world where they stabilize intra- and extra-cellular environments like biofilms or cell envelopes. To date, functional amyloids have largely been studied using optical microscopy techniques in vivo, or after removal from their biological context for higher-resolution studies in vitro. Furthermore, conventional microscopies only indirectly identify amyloids based on morphology or unspecific amyloid dyes. Here, the high chemical and spatial (≈20 nm) resolution of Infrared Nanospectroscopy (AFM-IR) to investigate functional amyloid from Escherichia coli (curli), Pseudomonas (Fap), and the Archaea Methanosaeta (MspA) in situ is exploited. It is demonstrated that AFM-IR identifies amyloid protein within single intact cells through their cross β-sheet secondary structure, which has a unique spectroscopic signature in the amide I band of protein. Using this approach, nanoscale-resolved chemical images and spectra of purified curli and Methanosaeta cell wall sheaths are provided. The results highlight significant differences in secondary structure between E. coli cells with and without curli. Taken together, these results suggest that AFM-IR is a new and powerful label-free tool for in situ investigations of the biophysical state of functional amyloid and biomolecules in general.
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Affiliation(s)
- Daniel E Otzen
- Interdisciplinary Nanoscience Center (iNANO), Aarhus University, Gustav Wieds Vej 14, Aarhus C, Aarhus, 8000, Denmark
| | - Morten S Dueholm
- Department of Chemistry and Bioscience, Aalborg University, Fredrik Bajers Vej 7H, Aalborg, 9220, Denmark
| | - Zahra Najarzadeh
- Interdisciplinary Nanoscience Center (iNANO), Aarhus University, Gustav Wieds Vej 14, Aarhus C, Aarhus, 8000, Denmark
| | - Tuomas P J Knowles
- Department of Chemistry, University of Cambridge, Cambridge, CB2 1EW, UK
- Cavendish Laboratory, University of Cambridge, Cambridge, CB30HE, UK
| | - Francesco Simone Ruggeri
- Department of Chemistry, University of Cambridge, Cambridge, CB2 1EW, UK
- Laboratory of Organic Chemistry, Wageningen University, Wageningen, WE 6703, the Netherlands
- Laboratory of Physical Chemistry, Wageningen University, Wageningen, WE 6703, the Netherlands
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145
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El Manaa W, Duplan E, Goiran T, Lauritzen I, Vaillant Beuchot L, Lacas-Gervais S, Morais VA, You H, Qi L, Salazar M, Ozcan U, Chami M, Checler F, Alves da Costa C. Transcription- and phosphorylation-dependent control of a functional interplay between XBP1s and PINK1 governs mitophagy and potentially impacts Parkinson disease pathophysiology. Autophagy 2021; 17:4363-4385. [PMID: 34030589 PMCID: PMC8726674 DOI: 10.1080/15548627.2021.1917129] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Parkinson disease (PD)-affected brains show consistent endoplasmic reticulum (ER) stress and mitophagic dysfunctions. The mechanisms underlying these perturbations and how they are directly linked remain a matter of questions. XBP1 is a transcription factor activated upon ER stress after unconventional splicing by the nuclease ERN1/IREα thereby yielding XBP1s, whereas PINK1 is a kinase considered as the sensor of mitochondrial physiology and a master gatekeeper of mitophagy process. We showed that XBP1s transactivates PINK1 in human cells, primary cultured neurons and mice brain, and triggered a pro-mitophagic phenotype that was fully dependent of endogenous PINK1. We also unraveled a PINK1-dependent phosphorylation of XBP1s that conditioned its nuclear localization and thereby, governed its transcriptional activity. PINK1-induced XBP1s phosphorylation occurred at residues reminiscent of, and correlated to, those phosphorylated in substantia nigra of sporadic PD-affected brains. Overall, our study delineated a functional loop between XBP1s and PINK1 governing mitophagy that was disrupted in PD condition.Abbreviations: 6OHDA: 6-hydroxydopamine; baf: bafilomycin A1; BECN1: beclin 1; CALCOCO2/NDP52: calcium binding and coiled-coil domain 2; CASP3: caspase 3; CCCP: carbonyl cyanide chlorophenylhydrazone; COX8A: cytochrome c oxidase subunit 8A; DDIT3/CHOP: DNA damage inducible transcript 3; EGFP: enhanced green fluorescent protein; ER: endoplasmic reticulum; ERN1/IRE1α: endoplasmic reticulum to nucleus signaling 1; FACS: fluorescence-activated cell sorting; HSPD1/HSP60: heat shock protein family D (Hsp60) member 1; MAP1LC3/LC3: microtubule associated protein 1 light chain 3; MFN2: mitofusin 2; OPTN: optineurin; PD: Parkinson disease; PINK1: PTEN-induced kinase 1; PCR: polymerase chain reaction:; PRKN: parkin RBR E3 ubiquitin protein ligase; XBP1s [p-S61A]: XBP1s phosphorylated at serine 61; XBP1s [p-T48A]: XBP1s phosphorylated at threonine 48; shRNA: short hairpin RNA, SQSTM1/p62: sequestosome 1; TIMM23: translocase of inner mitochondrial membrane 23; TM: tunicamycin; TMRM: tetramethyl rhodamine methylester; TOMM20: translocase of outer mitochondrial membrane 20; Toy: toyocamycin; TP: thapsigargin; UB: ubiquitin; UB (S65): ubiquitin phosphorylated at serine 65; UPR: unfolded protein response, XBP1: X-box binding protein 1; XBP1s: spliced X-box binding protein 1.
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Affiliation(s)
- Wejdane El Manaa
- INSERM, CNRS, IPMC, Team Labeled "Laboratory of Excellence (LABEX) Distalz", Sophia-Antipolis, Université Côte d'Azur, Valbonne, France
| | - Eric Duplan
- INSERM, CNRS, IPMC, Team Labeled "Laboratory of Excellence (LABEX) Distalz", Sophia-Antipolis, Université Côte d'Azur, Valbonne, France
| | - Thomas Goiran
- INSERM, CNRS, IPMC, Team Labeled "Laboratory of Excellence (LABEX) Distalz", Sophia-Antipolis, Université Côte d'Azur, Valbonne, France
| | - Inger Lauritzen
- INSERM, CNRS, IPMC, Team Labeled "Laboratory of Excellence (LABEX) Distalz", Sophia-Antipolis, Université Côte d'Azur, Valbonne, France
| | - Loan Vaillant Beuchot
- INSERM, CNRS, IPMC, Team Labeled "Laboratory of Excellence (LABEX) Distalz", Sophia-Antipolis, Université Côte d'Azur, Valbonne, France
| | | | - Vanessa Alexandra Morais
- Instituto de Medicina Molecular - João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisbon, Portugal
| | - Han You
- State Key Laboratory of Cellular Stress Biology, Innovation Center for Cell Signaling Network, School of Life Sciences, Xiamen University, Xiamen, Fujian, China
| | - Ling Qi
- Division of Metabolism, Endocrinology & Diabetes, University of Michigan, Ann Arbor, NY, USA
| | - Mario Salazar
- Division of Endocrinology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Umut Ozcan
- Division of Endocrinology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Mounia Chami
- INSERM, CNRS, IPMC, Team Labeled "Laboratory of Excellence (LABEX) Distalz", Sophia-Antipolis, Université Côte d'Azur, Valbonne, France
| | - Frédéric Checler
- INSERM, CNRS, IPMC, Team Labeled "Laboratory of Excellence (LABEX) Distalz", Sophia-Antipolis, Université Côte d'Azur, Valbonne, France
| | - Cristine Alves da Costa
- INSERM, CNRS, IPMC, Team Labeled "Laboratory of Excellence (LABEX) Distalz", Sophia-Antipolis, Université Côte d'Azur, Valbonne, France
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146
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Bhumkar A, Magnan C, Lau D, Jun ESW, Dzamko N, Gambin Y, Sierecki E. Single-Molecule Counting Coupled to Rapid Amplification Enables Detection of α-Synuclein Aggregates in Cerebrospinal Fluid of Parkinson's Disease Patients. Angew Chem Int Ed Engl 2021; 60:11874-11883. [PMID: 33511725 PMCID: PMC8251908 DOI: 10.1002/anie.202014898] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Revised: 01/13/2021] [Indexed: 12/16/2022]
Abstract
α-Synuclein aggregation is a hallmark of Parkinson's disease and a promising biomarker for early detection and assessment of disease progression. The prospect of a molecular test for Parkinson's disease is materializing with the recent developments of detection methods based on amplification of synuclein seeds (e.g. RT-QuIC or PMCA). Here we adapted single-molecule counting methods for the detection of α-synuclein aggregates in cerebrospinal fluid (CSF), using a simple 3D printed microscope. Single-molecule methods enable to probe the early events in the amplification process used in RT-QuIC and a precise counting of ThT-positive aggregates. Importantly, the use of single-molecule counting also allows a refined characterization of the samples and fingerprinting of the protein aggregates present in CSF of patients. The fingerprinting of size and reactivity of individual aggregate shows a unique signature for each PD patients compared to controls and may provide new insights on synucleinopathies in the future.
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Affiliation(s)
- Akshay Bhumkar
- EMBL-Australia node in Single Molecule Science and School of Medical SciencesThe University of New South WalesSydneyNSW2052Australia
| | - Chloe Magnan
- EMBL-Australia node in Single Molecule Science and School of Medical SciencesThe University of New South WalesSydneyNSW2052Australia
| | - Derrick Lau
- EMBL-Australia node in Single Molecule Science and School of Medical SciencesThe University of New South WalesSydneyNSW2052Australia
| | - Eugene Soh Wei Jun
- EMBL-Australia node in Single Molecule Science and School of Medical SciencesThe University of New South WalesSydneyNSW2052Australia
| | - Nicolas Dzamko
- Brain and Mind Centre and the School of Medical SciencesThe University of SydneySydneyNSW2006Australia
| | - Yann Gambin
- EMBL-Australia node in Single Molecule Science and School of Medical SciencesThe University of New South WalesSydneyNSW2052Australia
| | - Emma Sierecki
- EMBL-Australia node in Single Molecule Science and School of Medical SciencesThe University of New South WalesSydneyNSW2052Australia
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147
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Bhumkar A, Magnan C, Lau D, Jun ESW, Dzamko N, Gambin Y, Sierecki E. Single‐Molecule Counting Coupled to Rapid Amplification Enables Detection of α‐Synuclein Aggregates in Cerebrospinal Fluid of Parkinson's Disease Patients. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202014898] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Akshay Bhumkar
- EMBL-Australia node in Single Molecule Science and School of Medical Sciences The University of New South Wales Sydney NSW 2052 Australia
| | - Chloe Magnan
- EMBL-Australia node in Single Molecule Science and School of Medical Sciences The University of New South Wales Sydney NSW 2052 Australia
| | - Derrick Lau
- EMBL-Australia node in Single Molecule Science and School of Medical Sciences The University of New South Wales Sydney NSW 2052 Australia
| | - Eugene Soh Wei Jun
- EMBL-Australia node in Single Molecule Science and School of Medical Sciences The University of New South Wales Sydney NSW 2052 Australia
| | - Nicolas Dzamko
- Brain and Mind Centre and the School of Medical Sciences The University of Sydney Sydney NSW 2006 Australia
| | - Yann Gambin
- EMBL-Australia node in Single Molecule Science and School of Medical Sciences The University of New South Wales Sydney NSW 2052 Australia
| | - Emma Sierecki
- EMBL-Australia node in Single Molecule Science and School of Medical Sciences The University of New South Wales Sydney NSW 2052 Australia
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148
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Exploring the Release of Toxic Oligomers from α-Synuclein Fibrils with Antibodies and STED Microscopy. Life (Basel) 2021; 11:life11050431. [PMID: 34064766 PMCID: PMC8150853 DOI: 10.3390/life11050431] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2021] [Revised: 04/30/2021] [Accepted: 05/04/2021] [Indexed: 12/21/2022] Open
Abstract
α-Synuclein (αS) is an intrinsically disordered and highly dynamic protein involved in dopamine release at presynaptic terminals. The abnormal aggregation of αS as mature fibrils into intraneuronal inclusion bodies is directly linked to Parkinson’s disease. Increasing experimental evidence suggests that soluble oligomers formed early during the aggregation process are the most cytotoxic forms of αS. This study investigated the uptake by neuronal cells of pathologically relevant αS oligomers and fibrils exploiting a range of conformation-sensitive antibodies, and the super-resolution stimulated emission depletion (STED) microscopy. We found that prefibrillar oligomers promptly penetrate neuronal membranes, thus resulting in cell dysfunction. By contrast, fibril docking to the phospholipid bilayer is accompanied by αS conformational changes with a progressive release of A11-reactive oligomers, which can enter into the neurons and trigger cell impairment. Our data provide important evidence on the role of αS fibrils as a source of harmful oligomers, which resemble the intermediate conformers formed de novo during aggregation, underling the dynamic and reversible nature of protein aggregates responsible for α-synucleinopathies.
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149
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The differential solvent exposure of N-terminal residues provides "fingerprints" of alpha-synuclein fibrillar polymorphs. J Biol Chem 2021; 296:100737. [PMID: 33933456 PMCID: PMC8163981 DOI: 10.1016/j.jbc.2021.100737] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2021] [Revised: 04/15/2021] [Accepted: 04/28/2021] [Indexed: 01/13/2023] Open
Abstract
Synucleinopathies are neurodegenerative diseases characterized by the presence of intracellular deposits containing the protein alpha-synuclein (aSYN) within patients’ brains. It has been shown that aSYN can form structurally distinct fibrillar assemblies, also termed polymorphs. We previously showed that distinct aSYN polymorphs assembled in vitro, named fibrils, ribbons, and fibrils 91, differentially bind to and seed the aggregation of endogenous aSYN in neuronal cells, which suggests that distinct synucleinopathies may arise from aSYN polymorphs. In order to better understand the differential interactions of aSYN polymorphs with their partner proteins, we mapped aSYN polymorphs surfaces. We used limited proteolysis, hydrogen–deuterium exchange, and differential antibody accessibility to identify amino acids on their surfaces. We showed that the aSYN C-terminal region spanning residues 94 to 140 exhibited similarly high solvent accessibility in these three polymorphs. However, the N-terminal amino acid residues 1 to 38 of fibrils were exposed to the solvent, while only residues 1 to 18 within fibrils 91 were exposed, and no N-terminal residues within ribbons were solvent-exposed. It is likely that these differences in surface accessibility contribute to the differential binding of distinct aSYN polymorphs to partner proteins. We thus posit that the polypeptides exposed on the surface of distinct aSYN fibrillar polymorphs are comparable to fingerprints. Our findings have diagnostic and therapeutic potential, particularly in the prion-like propagation of fibrillar aSYN, as they can facilitate the design of ligands that specifically bind and distinguish between fibrillar polymorphs.
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150
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NMR unveils an N-terminal interaction interface on acetylated-α-synuclein monomers for recruitment to fibrils. Proc Natl Acad Sci U S A 2021; 118:2017452118. [PMID: 33903234 DOI: 10.1073/pnas.2017452118] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Amyloid fibril formation of α-synuclein (αS) is associated with multiple neurodegenerative diseases, including Parkinson's disease (PD). Growing evidence suggests that progression of PD is linked to cell-to-cell propagation of αS fibrils, which leads to seeding of endogenous intrinsically disordered monomer via templated elongation and secondary nucleation. A molecular understanding of the seeding mechanism and driving interactions is crucial to inhibit progression of amyloid formation. Here, using relaxation-based solution NMR experiments designed to probe large complexes, we probe weak interactions of intrinsically disordered acetylated-αS (Ac-αS) monomers with seeding-competent Ac-αS fibrils and seeding-incompetent off-pathway oligomers to identify Ac-αS monomer residues at the binding interface. Under conditions that favor fibril elongation, we determine that the first 11 N-terminal residues on the monomer form a common binding site for both fibrils and off-pathway oligomers. Additionally, the presence of off-pathway oligomers within a fibril seeding environment suppresses seeded amyloid formation, as observed through thioflavin-T fluorescence experiments. This highlights that off-pathway αS oligomers can act as an auto-inhibitor against αS fibril elongation. Based on these data taken together with previous results, we propose a model in which Ac-αS monomer recruitment to the fibril is driven by interactions between the intrinsically disordered monomer N terminus and the intrinsically disordered flanking regions (IDR) on the fibril surface. We suggest that this monomer recruitment may play a role in the elongation of amyloid fibrils and highlight the potential of the IDRs of the fibril as important therapeutic targets against seeded amyloid formation.
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