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Sandoval A, Duran P, Corzo-López A, Fernández-Gallardo M, Muñoz-Herrera D, Leyva-Leyva M, González-Ramírez R, Felix R. The role of voltage-gated calcium channels in the pathogenesis of Parkinson's disease. Int J Neurosci 2024; 134:452-461. [PMID: 35993158 DOI: 10.1080/00207454.2022.2115905] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Revised: 06/07/2022] [Accepted: 07/29/2022] [Indexed: 10/15/2022]
Abstract
Aim: Voltage-gated calcium (CaV) channels play an essential role in maintaining calcium homeostasis and regulating numerous physiological processes in neurons. Therefore, dysregulation of calcium signaling is relevant in many neurological disorders, including Parkinson's disease (PD). This review aims to introduce the role of CaV channels in PD and discuss some novel aspects of channel regulation and its impact on the molecular pathophysiology of the disease. Methods: an exhaustive search of the literature in the field was carried out using the PubMed database of The National Center for Biotechnology Information. Systematic searches were performed from the initial date of publication to May 2022. Results: Although α-synuclein aggregates are the main feature of PD, L-type calcium (CaV1) channels seem to play an essential role in the pathogenesis of PD. Changes in the functional expression of CaV1.3 channels alter Calcium homeostasis and contribute to the degeneration of dopaminergic neurons. Furthermore, recent studies suggest that CaV channel trafficking towards the cell membrane depends on the activity of the ubiquitin-proteasome system (UPS). In PD, there is an increase in the expression of L-type channels associated with a decrease in the expression of Parkin, an E3 enzyme of the UPS. Therefore, a link between Parkin and CaV channels could play a fundamental role in the pathogenesis of PD and, as such, could be a potentially attractive target for therapeutic intervention. Conclusion: The study of alterations in the functional expression of CaV channels will provide a framework to understand better the neurodegenerative processes that occur in PD and a possible path toward identifying new therapeutic targets to treat this condition.
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Affiliation(s)
- Alejandro Sandoval
- School of Medicine FES Iztacala, National Autonomous University of Mexico (UNAM), Tlalnepantla, Mexico
| | - Paz Duran
- Department of Cell Biology, Centre for Research and Advanced Studies (Cinvestav), Mexico City, Mexico
| | - Alejandra Corzo-López
- Department of Cell Biology, Centre for Research and Advanced Studies (Cinvestav), Mexico City, Mexico
| | | | - David Muñoz-Herrera
- Department of Cell Biology, Centre for Research and Advanced Studies (Cinvestav), Mexico City, Mexico
| | - Margarita Leyva-Leyva
- Department of Molecular Biology and Histocompatibility, "Dr. Manuel Gea González" General Hospital, Mexico City, Mexico
| | - Ricardo González-Ramírez
- Department of Molecular Biology and Histocompatibility, "Dr. Manuel Gea González" General Hospital, Mexico City, Mexico
| | - Ricardo Felix
- Department of Cell Biology, Centre for Research and Advanced Studies (Cinvestav), Mexico City, Mexico
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2
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Reyes-Resina I, Lillo J, Raïch I, Rebassa JB, Navarro G. The Expression and Functionality of CB 1R-NMDAR Complexes Are Decreased in A Parkinson's Disease Model. Int J Mol Sci 2024; 25:3021. [PMID: 38474266 PMCID: PMC10931566 DOI: 10.3390/ijms25053021] [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: 02/04/2024] [Revised: 03/01/2024] [Accepted: 03/03/2024] [Indexed: 03/14/2024] Open
Abstract
One of the hallmarks of Parkinson's disease (PD) is the alteration in the expression and function of NMDA receptor (NMDAR) and cannabinoid receptor 1 (CB1R). The presence of CB1R-NMDAR complexes has been described in neuronal primary cultures. The activation of CB1R in CB1R-NMDAR complexes was suggested to counteract the detrimental NMDAR overactivation in an AD mice model. Thus, we aimed to explore the role of this receptor complex in PD. By using Bioluminescence Resonance Energy Transfer (BRET) assay, it was demonstrated that α-synuclein induces a reorganization of the CB1R-NMDAR complex in transfected HEK-293T cells. Moreover, α-synuclein treatment induced a decrease in the cAMP and MAP kinase (MAPK) signaling of both CB1R and NMDAR not only in transfected cells but also in neuronal primary cultures. Finally, the interaction between CB1R and NMDAR was studied by Proximity Ligation Assay (PLA) in neuronal primary cultures, where it was observed that the expression of CB1R-NMDAR complexes was decreased upon α-synuclein treatment. These results point to a role of CB1R-NMDAR complexes as a new therapeutic target in Parkinson's disease.
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Affiliation(s)
- Irene Reyes-Resina
- Department of Biochemistry and Physiology, School of Pharmacy and Food Sciences, Universitat de Barcelona, 08028 Barcelona, Spain; (I.R.); (J.B.R.)
- Network Center for Biomedical Research in Neurodegenerative Diseases, CiberNed, Spanish National Health Institute Carlos III, Av. Monforte de Lemos, 3-5, 28029 Madrid, Spain;
- Institut de Neurociències UB, Campus Mundet, Passeig de la Vall d’Hebron 171, 08035 Barcelona, Spain
| | - Jaume Lillo
- Network Center for Biomedical Research in Neurodegenerative Diseases, CiberNed, Spanish National Health Institute Carlos III, Av. Monforte de Lemos, 3-5, 28029 Madrid, Spain;
- Institut de Neurociències UB, Campus Mundet, Passeig de la Vall d’Hebron 171, 08035 Barcelona, Spain
- Molecular Neurobiology Laboratory, Department Biochemistry and Molecular Biomedicine, Facultat de Biologia, Universitat de Barcelona, 08028 Barcelona, Spain
| | - Iu Raïch
- Department of Biochemistry and Physiology, School of Pharmacy and Food Sciences, Universitat de Barcelona, 08028 Barcelona, Spain; (I.R.); (J.B.R.)
- Network Center for Biomedical Research in Neurodegenerative Diseases, CiberNed, Spanish National Health Institute Carlos III, Av. Monforte de Lemos, 3-5, 28029 Madrid, Spain;
- Institut de Neurociències UB, Campus Mundet, Passeig de la Vall d’Hebron 171, 08035 Barcelona, Spain
| | - Joan Biel Rebassa
- Department of Biochemistry and Physiology, School of Pharmacy and Food Sciences, Universitat de Barcelona, 08028 Barcelona, Spain; (I.R.); (J.B.R.)
- Network Center for Biomedical Research in Neurodegenerative Diseases, CiberNed, Spanish National Health Institute Carlos III, Av. Monforte de Lemos, 3-5, 28029 Madrid, Spain;
- Institut de Neurociències UB, Campus Mundet, Passeig de la Vall d’Hebron 171, 08035 Barcelona, Spain
| | - Gemma Navarro
- Department of Biochemistry and Physiology, School of Pharmacy and Food Sciences, Universitat de Barcelona, 08028 Barcelona, Spain; (I.R.); (J.B.R.)
- Network Center for Biomedical Research in Neurodegenerative Diseases, CiberNed, Spanish National Health Institute Carlos III, Av. Monforte de Lemos, 3-5, 28029 Madrid, Spain;
- Institut de Neurociències UB, Campus Mundet, Passeig de la Vall d’Hebron 171, 08035 Barcelona, Spain
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3
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Calabresi P, Mechelli A, Natale G, Volpicelli-Daley L, Di Lazzaro G, Ghiglieri V. Alpha-synuclein in Parkinson's disease and other synucleinopathies: from overt neurodegeneration back to early synaptic dysfunction. Cell Death Dis 2023; 14:176. [PMID: 36859484 PMCID: PMC9977911 DOI: 10.1038/s41419-023-05672-9] [Citation(s) in RCA: 76] [Impact Index Per Article: 76.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Revised: 01/18/2023] [Accepted: 02/09/2023] [Indexed: 03/03/2023]
Abstract
Although the discovery of the critical role of α-synuclein (α-syn) in the pathogenesis of Parkinson's disease (PD) is now twenty-five years old, it still represents a milestone in PD research. Abnormal forms of α-syn trigger selective and progressive neuronal death through mitochondrial impairment, lysosomal dysfunction, and alteration of calcium homeostasis not only in PD but also in other α-syn-related neurodegenerative disorders such as dementia with Lewy bodies, multiple system atrophy, pure autonomic failure, and REM sleep behavior disorder. Furthermore, α-syn-dependent early synaptic and plastic alterations and the underlying mechanisms preceding overt neurodegeneration have attracted great interest. In particular, the presence of early inflammation in experimental models and PD patients, occurring before deposition and spreading of α-syn, suggests a mechanistic link between inflammation and synaptic dysfunction. The knowledge of these early mechanisms is of seminal importance to support the research on reliable biomarkers to precociously identify the disease and possible disease-modifying therapies targeting α-syn. In this review, we will discuss these critical issues, providing a state of the art of the role of this protein in early PD and other synucleinopathies.
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Affiliation(s)
- Paolo Calabresi
- Sezione di Neurologia, Dipartimento di Neuroscienze, Facoltà di Medicina e Chirurgia, Università Cattolica del Sacro Cuore, Rome, 00168, Italy. .,Neurologia, Fondazione Policlinico Universitario Agostino Gemelli IRCCS, Rome, 00168, Italy.
| | - Alessandro Mechelli
- Dipartimento di Scienze Mediche e Chirurgiche, Istituto di Neurologia, Università "Magna Graecia", Catanzaro, Italy
| | - Giuseppina Natale
- Sezione di Neurologia, Dipartimento di Neuroscienze, Facoltà di Medicina e Chirurgia, Università Cattolica del Sacro Cuore, Rome, 00168, Italy
| | - Laura Volpicelli-Daley
- Center for Neurodegeneration and Experimental Therapeutics, University of Alabama at Birmingham, Birmingham, AL, 35294, USA
| | - Giulia Di Lazzaro
- Neurologia, Fondazione Policlinico Universitario Agostino Gemelli IRCCS, Rome, 00168, Italy
| | - Veronica Ghiglieri
- Neurologia, Fondazione Policlinico Universitario Agostino Gemelli IRCCS, Rome, 00168, Italy.,Università Telematica San Raffaele, Rome, 00166, Italy
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4
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Tomagra G, Franchino C, Cesano F, Chiarion G, de lure A, Carbone E, Calabresi P, Mesin L, Picconi B, Marcantoni A, Carabelli V. Alpha-synuclein oligomers alter the spontaneous firing discharge of cultured midbrain neurons. Front Cell Neurosci 2023; 17:1078550. [PMID: 36744002 PMCID: PMC9896582 DOI: 10.3389/fncel.2023.1078550] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2022] [Accepted: 01/06/2023] [Indexed: 01/21/2023] Open
Abstract
The aim of this work was to monitor the effects of extracellular α-synuclein on the firing activity of midbrain neurons dissociated from substantia nigra TH-GFP mice embryos and cultured on microelectrode arrays (MEA). We monitored the spontaneous firing discharge of the network for 21 days after plating and the role of glutamatergic and GABAergic inputs in regulating burst generation and network synchronism. Addition of GABA A , AMPA and NMDA antagonists did not suppress the spontaneous activity but allowed to identify three types of neurons that exhibited different modalities of firing and response to applied L-DOPA: high-rate (HR) neurons, low-rate pacemaking (LR-p), and low-rate non-pacemaking (LR-np) neurons. Most HR neurons were insensitive to L-DOPA, while the majority of LR-p neurons responded with a decrease of the firing discharge; less defined was the response of LR-np neurons. The effect of exogenous α-synuclein (α-syn) on the firing discharge of midbrain neurons was then studied by varying the exposure time (0-48 h) and the α-syn concentration (0.3-70 μM), while the formation of α-syn oligomers was monitored by means of AFM. Independently of the applied concentration, acute exposure to α-syn monomers did not exert any effect on the spontaneous firing rate of HR, LR-p, and LR-np neurons. On the contrary, after 48 h exposure, the firing activity was drastically altered at late developmental stages (14 days in vitro, DIV, neurons): α-syn oligomers progressively reduced the spontaneous firing discharge (IC50 = 1.03 μM), impaired burst generation and network synchronism, proportionally to the increased oligomer/monomer ratio. Different effects were found on early-stage developed neurons (9 DIV), whose firing discharge remained unaltered, regardless of the applied α-syn concentration and the exposure time. Our findings unravel, for the first time, the variable effects of exogenous α-syn at different stages of midbrain network development and provide new evidence for the early detection of neuronal function impairment associated to aggregated forms of α-syn.
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Affiliation(s)
- Giulia Tomagra
- Drug Science Department, University of Torino, Turin, Italy
- Nanostructured Interfaces and Surfaces Inter-Departmental Research Centre, Turin, Italy
| | | | - Federico Cesano
- Nanostructured Interfaces and Surfaces Inter-Departmental Research Centre, Turin, Italy
- Department of Chemistry and INSTM-UdR Torino, Turin, Italy
| | - Giovanni Chiarion
- Mathematical Biology and Physiology, Department of Electronics and Telecommunications, Turin, Italy
| | - Antonio de lure
- Laboratory Experimental Neurophysiology, IRCCS San Raffaele Rome, Rome, Italy
| | - Emilio Carbone
- Drug Science Department, University of Torino, Turin, Italy
- Nanostructured Interfaces and Surfaces Inter-Departmental Research Centre, Turin, Italy
| | - Paolo Calabresi
- Neurological Clinic, Fondazione Policlinico Universitario Agostino Gemelli IRCCS, Rome, Italy
- Neurology, Department of Neuroscience, Faculty of Medicine, Università Cattolica del “Sacro Cuore,”Rome, Italy
| | - Luca Mesin
- Mathematical Biology and Physiology, Department of Electronics and Telecommunications, Turin, Italy
| | - Barbara Picconi
- Laboratory Experimental Neurophysiology, IRCCS San Raffaele Rome, Rome, Italy
- Dipartimento di Scienze Umane e Promozione della Qualitá della Vita, Telematic University San Raffaele Roma, Rome, Italy
| | - Andrea Marcantoni
- Drug Science Department, University of Torino, Turin, Italy
- Nanostructured Interfaces and Surfaces Inter-Departmental Research Centre, Turin, Italy
| | - Valentina Carabelli
- Drug Science Department, University of Torino, Turin, Italy
- Nanostructured Interfaces and Surfaces Inter-Departmental Research Centre, Turin, Italy
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5
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The Consequences of GBA Deficiency in the Autophagy-Lysosome System in Parkinson's Disease Associated with GBA. Cells 2023; 12:cells12010191. [PMID: 36611984 PMCID: PMC9818455 DOI: 10.3390/cells12010191] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Revised: 12/27/2022] [Accepted: 12/31/2022] [Indexed: 01/05/2023] Open
Abstract
GBA gene variants were the first genetic risk factor for Parkinson's disease. GBA encodes the lysosomal enzyme glucocerebrosidase (GBA), which is involved in sphingolipid metabolism. GBA exhibits a complex physiological function that includes not only the degradation of its substrate glucosylceramide but also the metabolism of other sphingolipids and additional lipids such as cholesterol, particularly when glucocerebrosidase activity is deficient. In the context of Parkinson's disease associated with GBA, the loss of GBA activity has been associated with the accumulation of α-synuclein species. In recent years, several hypotheses have proposed alternative and complementary pathological mechanisms to explain why lysosomal enzyme mutations lead to α-synuclein accumulation and become important risk factors in Parkinson's disease etiology. Classically, loss of GBA activity has been linked to a dysfunctional autophagy-lysosome system and to a subsequent decrease in autophagy-dependent α-synuclein turnover; however, several other pathological mechanisms underlying GBA-associated parkinsonism have been proposed. This review summarizes and discusses the different hypotheses with a special focus on autophagy-dependent mechanisms, as well as autophagy-independent mechanisms, where the role of other players such as sphingolipids, cholesterol and other GBA-related proteins make important contributions to Parkinson's disease pathogenesis.
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6
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Correa BH, Moreira CR, Hildebrand ME, Vieira LB. The Role of Voltage-Gated Calcium Channels in Basal Ganglia Neurodegenerative Disorders. Curr Neuropharmacol 2023; 21:183-201. [PMID: 35339179 PMCID: PMC10190140 DOI: 10.2174/1570159x20666220327211156] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Revised: 01/11/2022] [Accepted: 03/14/2022] [Indexed: 11/22/2022] Open
Abstract
Calcium (Ca2+) plays a central role in regulating many cellular processes and influences cell survival. Several mechanisms can disrupt Ca2+ homeostasis to trigger cell death, including oxidative stress, mitochondrial damage, excitotoxicity, neuroinflammation, autophagy, and apoptosis. Voltage-gated Ca2+ channels (VGCCs) act as the main source of Ca2+ entry into electrically excitable cells, such as neurons, and they are also expressed in glial cells such as astrocytes and oligodendrocytes. The dysregulation of VGCC activity has been reported in both Parkinson's disease (PD) and Huntington's (HD). PD and HD are progressive neurodegenerative disorders (NDs) of the basal ganglia characterized by motor impairment as well as cognitive and psychiatric dysfunctions. This review will examine the putative role of neuronal VGCCs in the pathogenesis and treatment of central movement disorders, focusing on PD and HD. The link between basal ganglia disorders and VGCC physiology will provide a framework for understanding the neurodegenerative processes that occur in PD and HD, as well as a possible path towards identifying new therapeutic targets for the treatment of these debilitating disorders.
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Affiliation(s)
- Bernardo H.M. Correa
- Department of Pharmacology, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | - Carlos Roberto Moreira
- Department of Pharmacology, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
| | | | - Luciene Bruno Vieira
- Department of Pharmacology, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
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7
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Pilch KS, Ramgoolam KH, Dolphin AC. Involvement of Ca V 2.2 channels and α 2 δ-1 in homeostatic synaptic plasticity in cultured hippocampal neurons. J Physiol 2022; 600:5333-5351. [PMID: 36377048 PMCID: PMC10107484 DOI: 10.1113/jp283600] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2022] [Accepted: 11/08/2022] [Indexed: 11/16/2022] Open
Abstract
In the mammalian brain, presynaptic CaV 2 channels play a pivotal role in synaptic transmission by mediating fast neurotransmitter exocytosis via influx of Ca2+ into the active zone of presynaptic terminals. However, the distribution and modulation of CaV 2.2 channels at plastic hippocampal synapses remains to be elucidated. Here, we assess CaV 2.2 channels during homeostatic synaptic plasticity, a compensatory form of homeostatic control preventing excessive or insufficient neuronal activity during which extensive active zone remodelling has been described. We show that chronic silencing of neuronal activity in mature hippocampal cultures resulted in elevated presynaptic Ca2+ transients, mediated by increased levels of CaV 2.2 channels at the presynaptic site. This work focused further on the role of α2 δ-1 subunits, important regulators of synaptic transmission and CaV 2.2 channel abundance at the presynaptic membrane. We found that α2 δ-1 overexpression reduces the contribution of CaV 2.2 channels to total Ca2+ flux without altering the amplitude of the Ca2+ transients. Levels of endogenous α2 δ-1 decreased during homeostatic synaptic plasticity, whereas the overexpression of α2 δ-1 prevented homeostatic synaptic plasticity in hippocampal neurons. Together, this study reveals a key role for CaV 2.2 channels and novel roles for α2 δ-1 during synaptic plastic adaptation. KEY POINTS: The roles of CaV 2.2 channels and α2 δ-1 in homeostatic synaptic plasticity in hippocampal neurons in culture were examined. Chronic silencing of neuronal activity resulted in elevated presynaptic Ca2+ transients, mediated by increased levels of CaV 2.2 channels at presynaptic sites. The level of endogenous α2 δ-1 decreased during homeostatic synaptic plasticity, whereas overexpression of α2 δ-1 prevented homeostatic synaptic plasticity in hippocampal neurons. Together, this study reveals a key role for CaV 2.2 channels and novel roles for α2 δ-1 during synaptic plastic adaptation.
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Affiliation(s)
- Kjara S. Pilch
- Department of NeurosciencePhysiology and PharmacologyUniversity College LondonLondonUK
| | - Krishma H. Ramgoolam
- Department of NeurosciencePhysiology and PharmacologyUniversity College LondonLondonUK
| | - Annette C. Dolphin
- Department of NeurosciencePhysiology and PharmacologyUniversity College LondonLondonUK
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8
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Kulkarni AS, Burns MR, Brundin P, Wesson DW. Linking α-synuclein-induced synaptopathy and neural network dysfunction in early Parkinson’s disease. Brain Commun 2022; 4:fcac165. [PMID: 35822101 PMCID: PMC9272065 DOI: 10.1093/braincomms/fcac165] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2021] [Revised: 03/11/2022] [Accepted: 06/20/2022] [Indexed: 01/18/2023] Open
Abstract
Abstract
The prodromal phase of Parkinson’s disease is characterized by aggregation of the misfolded pathogenic protein α-synuclein in select neural centres, co-occurring with non-motor symptoms including sensory and cognitive loss, and emotional disturbances. It is unclear whether neuronal loss is significant during the prodrome. Underlying these symptoms are synaptic impairments and aberrant neural network activity. However, the relationships between synaptic defects and network-level perturbations are not established. In experimental models, pathological α-synuclein not only impacts neurotransmission at the synaptic level, but also leads to changes in brain network-level oscillatory dynamics—both of which likely contribute to non-motor deficits observed in Parkinson’s disease. Here we draw upon research from both human subjects and experimental models to propose a ‘synapse to network prodrome cascade’ wherein before overt cell death, pathological α-synuclein induces synaptic loss and contributes to aberrant network activity, which then gives rise to prodromal symptomology. As the disease progresses, abnormal patterns of neural activity ultimately lead to neuronal loss and clinical progression of disease. Finally, we outline goals and research needed to unravel the basis of functional impairments in Parkinson’s disease and other α-synucleinopathies.
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Affiliation(s)
- Aishwarya S Kulkarni
- Department of Pharmacology & Therapeutics, University of Florida , 1200 Newell Dr, Gainesville, FL 32610 , USA
| | - Matthew R Burns
- Department of Neurology, University of Florida , 1200 Newell Dr, Gainesville, FL 32610 , USA
- Norman Fixel Institute for Neurological Disorders, University of Florida , 1200 Newell Dr, Gainesville, FL 32610 , USA
| | - Patrik Brundin
- Pharma Research and Early Development (pRED), F. Hoffman-La Roche , Little Falls, NJ , USA
| | - Daniel W Wesson
- Department of Pharmacology & Therapeutics, University of Florida , 1200 Newell Dr, Gainesville, FL 32610 , USA
- Norman Fixel Institute for Neurological Disorders, University of Florida , 1200 Newell Dr, Gainesville, FL 32610 , USA
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9
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α-Synuclein induced cholesterol lowering increases tonic and reduces depolarization-evoked synaptic vesicle recycling and glutamate release. NPJ Parkinsons Dis 2022; 8:71. [PMID: 35672421 PMCID: PMC9174203 DOI: 10.1038/s41531-022-00334-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Accepted: 05/17/2022] [Indexed: 02/07/2023] Open
Abstract
α-Synuclein (α-syn) is a key molecule linked to Parkinson's disease pathology. Physiologically, the monomeric α-syn in the presynaptic termini is involved in regulation of neurotransmission, but the pathophysiology of extracellular monomeric α-syn is still unknown. Utilizing both in vivo and in vitro approaches, we investigated how extracellular α-syn impact presynaptic structure and function. Our data revealed that treatment with exogenous α-syn leads to increased tonic and decreased depolarization-evoked synaptic vesicle (SV) recycling and glutamate release. This was associated with mobilization of molecularly distinct SV pools and reorganization of active zone components. Our study also showed that exogenous α-syn impaired neuronal cholesterol level and that the cholesterol binding domain of α-syn was sufficient to exert the same presynaptic phenotype as the full-length protein. The present study sheds new light on physiological functions of extracellular α-syn in overall maintenance of presynaptic activity that involves the reorganization of both presynaptic compartment and cholesterol-rich plasma membrane domains.
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10
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Alpha-synuclein increases in rodent and human spinal cord injury and promotes inflammation and tissue loss. Sci Rep 2021; 11:11720. [PMID: 34083630 PMCID: PMC8175699 DOI: 10.1038/s41598-021-91116-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Accepted: 05/17/2021] [Indexed: 12/27/2022] Open
Abstract
Synucleinopathies are neurodegenerative diseases in which α-synuclein protein accumulates in neurons and glia. In these diseases, α-synuclein forms dense intracellular aggregates that are disease hallmarks and actively contribute to tissue pathology. Interestingly, many pathological mechanisms, including iron accumulation and lipid peroxidation, are shared between classical synucleinopathies such as Alzheimer’s disease, Parkinson’s disease and traumatic spinal cord injury (SCI). However, to date, no studies have determined if α-synuclein accumulation occurs after human SCI. To examine this, cross-sections from injured and non-injured human spinal cords were immunolabeled for α-synuclein. This showed robust α-synuclein accumulation in profiles resembling axons and astrocytes in tissue surrounding the injury, revealing that α-synuclein markedly aggregates in traumatically injured human spinal cords. We also detected significant iron deposition in the injury site, a known catalyst for α-synuclein aggregation. Next a rodent SCI model mimicking the histological features of human SCI revealed aggregates and structurally altered monomers of α-synuclein are present after SCI. To determine if α-synuclein exacerbates SCI pathology, α-synuclein knockout mice were tested. Compared to wild type mice, α-synuclein knockout mice had significantly more spared axons and neurons and lower pro-inflammatory mediators, macrophage accumulation, and iron deposition in the injured spinal cord. Interestingly, locomotor analysis revealed that α-synuclein may be essential for dopamine-mediated hindlimb function after SCI. Collectively, the marked upregulation and long-lasting accumulation of α-synuclein and iron suggests that SCI may fit within the family of synucleinopathies and offer new therapeutic targets for promoting neuron preservation and improving function after spinal trauma.
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Neurons and Glia Interplay in α-Synucleinopathies. Int J Mol Sci 2021; 22:ijms22094994. [PMID: 34066733 PMCID: PMC8125822 DOI: 10.3390/ijms22094994] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Revised: 04/29/2021] [Accepted: 05/04/2021] [Indexed: 11/16/2022] Open
Abstract
Accumulation of the neuronal presynaptic protein alpha-synuclein within proteinaceous inclusions represents the key histophathological hallmark of a spectrum of neurodegenerative disorders, referred to by the umbrella term a-synucleinopathies. Even though alpha-synuclein is expressed predominantly in neurons, pathological aggregates of the protein are also found in the glial cells of the brain. In Parkinson's disease and dementia with Lewy bodies, alpha-synuclein accumulates mainly in neurons forming the Lewy bodies and Lewy neurites, whereas in multiple system atrophy, the protein aggregates mostly in the glial cytoplasmic inclusions within oligodendrocytes. In addition, astrogliosis and microgliosis are found in the synucleinopathy brains, whereas both astrocytes and microglia internalize alpha-synuclein and contribute to the spread of pathology. The mechanisms underlying the pathological accumulation of alpha-synuclein in glial cells that under physiological conditions express low to non-detectable levels of the protein are an area of intense research. Undoubtedly, the presence of aggregated alpha-synuclein can disrupt glial function in general and can contribute to neurodegeneration through numerous pathways. Herein, we summarize the current knowledge on the role of alpha-synuclein in both neurons and glia, highlighting the contribution of the neuron-glia connectome in the disease initiation and progression, which may represent potential therapeutic target for a-synucleinopathies.
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12
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Threlfell S, Mohammadi AS, Ryan BJ, Connor-Robson N, Platt NJ, Anand R, Serres F, Sharp T, Bengoa-Vergniory N, Wade-Martins R, Ewing A, Cragg SJ, Brimblecombe KR. Striatal Dopamine Transporter Function Is Facilitated by Converging Biology of α-Synuclein and Cholesterol. Front Cell Neurosci 2021; 15:658244. [PMID: 33935654 PMCID: PMC8081845 DOI: 10.3389/fncel.2021.658244] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Accepted: 03/22/2021] [Indexed: 11/20/2022] Open
Abstract
Striatal dopamine transporters (DAT) powerfully regulate dopamine signaling, and can contribute risk to degeneration in Parkinson's disease (PD). DATs can interact with the neuronal protein α-synuclein, which is associated with the etiology and molecular pathology of idiopathic and familial PD. Here, we tested whether DAT function in governing dopamine (DA) uptake and release is modified in a human-α-synuclein-overexpressing (SNCA-OVX) transgenic mouse model of early PD. Using fast-scan cyclic voltammetry (FCV) in ex vivo acute striatal slices to detect DA release, and biochemical assays, we show that several aspects of DAT function are promoted in SNCA-OVX mice. Compared to background control α-synuclein-null mice (Snca-null), the SNCA-OVX mice have elevated DA uptake rates, and more pronounced effects of DAT inhibitors on evoked extracellular DA concentrations ([DA]o) and on short-term plasticity (STP) in DA release, indicating DATs play a greater role in limiting DA release and in driving STP. We found that DAT membrane levels and radioligand binding sites correlated with α-synuclein level. Furthermore, DAT function in Snca-null and SNCA-OVX mice could also be promoted by applying cholesterol, and using Tof-SIMS we found genotype-differences in striatal lipids, with lower striatal cholesterol in SNCA-OVX mice. An inhibitor of cholesterol efflux transporter ABCA1 or a cholesterol chelator in SNCA-OVX mice reduced the effects of DAT-inhibitors on evoked [DA]o. Together these data indicate that human α-synuclein in a mouse model of PD promotes striatal DAT function, in a manner supported by extracellular cholesterol, suggesting converging biology of α-synuclein and cholesterol that regulates DAT function and could impact DA function and PD pathophysiology.
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Affiliation(s)
- Sarah Threlfell
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
- Oxford Parkinson’s Disease Centre, Medical Sciences Division, University of Oxford, Oxford, United Kingdom
| | - Amir Saeid Mohammadi
- Department of Chemistry and Chemical Engineering, Chalmers University of Technology, Gothenburg, Sweden
| | - Brent J. Ryan
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
- Oxford Parkinson’s Disease Centre, Medical Sciences Division, University of Oxford, Oxford, United Kingdom
| | - Natalie Connor-Robson
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
- Oxford Parkinson’s Disease Centre, Medical Sciences Division, University of Oxford, Oxford, United Kingdom
| | - Nicola J. Platt
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
| | - Rishi Anand
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
| | - Florence Serres
- University Department of Pharmacology, University of Oxford, Oxford, United Kingdom
| | - Trevor Sharp
- University Department of Pharmacology, University of Oxford, Oxford, United Kingdom
| | - Nora Bengoa-Vergniory
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
- Oxford Parkinson’s Disease Centre, Medical Sciences Division, University of Oxford, Oxford, United Kingdom
| | - Richard Wade-Martins
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
- Oxford Parkinson’s Disease Centre, Medical Sciences Division, University of Oxford, Oxford, United Kingdom
| | - Andrew Ewing
- Department of Chemistry and Molecular Biology, University of Gothenburg, Gothenburg, Sweden
| | - Stephanie J. Cragg
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
- Oxford Parkinson’s Disease Centre, Medical Sciences Division, University of Oxford, Oxford, United Kingdom
| | - Katherine R. Brimblecombe
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
- Oxford Parkinson’s Disease Centre, Medical Sciences Division, University of Oxford, Oxford, United Kingdom
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13
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Bozelli JC, Kamski-Hennekam E, Melacini G, Epand RM. α-Synuclein and neuronal membranes: Conformational flexibilities in health and disease. Chem Phys Lipids 2021; 235:105034. [PMID: 33434528 DOI: 10.1016/j.chemphyslip.2020.105034] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Revised: 12/15/2020] [Accepted: 12/23/2020] [Indexed: 02/08/2023]
Abstract
Parkinson's disease (PD) is the second most common neurodegenerative disease. Currently, PD has no treatment. The neuronal protein α-synuclein (αS) plays an important role in PD. However, the molecular mechanisms governing its physiological and pathological roles are not fully understood. It is becoming widely acknowledged that the biological roles of αS involve interactions with biological membranes. In these biological processes there is a fine-tuned interplay between lipids affecting the properties of αS and αS affecting lipid metabolism, αS binding to membranes, and membrane damage. In this review, the intricate interactions between αS and membranes will be reviewed and a discussion of the relationship between αS and neuronal membrane structural plasticity in health and disease will be made. It is proposed that in healthy neurons the conformational flexibilities of αS and the neuronal membranes are coupled to assist the physiological roles of αS. However, in circumstances where their conformational flexibilities are decreased or uncoupled, there is a shift toward cell toxicity. Strategies to modulate toxic αS-membrane interactions are potential approaches for the development of new therapies for PD. Future work using specific αS molecular species as well as membranes with specific physicochemical properties should widen our understanding of the intricate biological roles of αS which, in turn, would propel the development of new strategies for the treatment of PD.
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Affiliation(s)
- José Carlos Bozelli
- Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, ON, L8S 4K1, Canada
| | - Evelyn Kamski-Hennekam
- Department of Chemistry and Chemical Biology, McMaster University, Hamilton, ON, L8S 4M1, Canada
| | - Giuseppe Melacini
- Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, ON, L8S 4K1, Canada; Department of Chemistry and Chemical Biology, McMaster University, Hamilton, ON, L8S 4M1, Canada.
| | - Richard M Epand
- Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, ON, L8S 4K1, Canada.
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14
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Asico LD, Rozyyev S, Crusan AM, Jose PA, Villar VAM. Elucidating the Role of Lipid Rafts on G Protein-Coupled Receptor Function in the Mouse Kidney: An In Vivo Approach. Methods Mol Biol 2021; 2187:187-206. [PMID: 32770507 DOI: 10.1007/978-1-0716-0814-2_10] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Numerous G protein-coupled receptors (GPCRs) and GPCR-signaling molecules reside in lipid rafts and thus, are inherently regulated in these microdomains. However, the limitations of current methods to investigate lipid raft biology and GPCR activity in situ have hindered the complete understanding of the molecular underpinnings of GPCR trafficking and signaling, especially in the whole organism. This book chapter details an innovative in vivo approach to study the crucial role of lipid rafts on the workings of GPCRs in the mouse kidney. This protocol involves the use of a modified mini osmotic pump to deliver an agent that selectively disrupts the lipid raft in the kidney.
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Affiliation(s)
- Laureano D Asico
- Division of Renal Diseases and Hypertension, School of Medicine and Health Sciences, The George Washington University, Washington, DC, USA.
| | - Selim Rozyyev
- Division of Renal Diseases and Hypertension, School of Medicine and Health Sciences, The George Washington University, Washington, DC, USA.,Sheikh Zayed Institute for Pediatric Surgical Innovation, Children's National Health System, Washington, DC, USA
| | - Annabelle M Crusan
- Research Animal Facility, The Children's Research Institute, Children's National Health System, Washington, DC, USA
| | - Pedro A Jose
- Division of Renal Diseases and Hypertension, School of Medicine and Health Sciences, The George Washington University, Washington, DC, USA
| | - Van Anthony M Villar
- Division of Renal Diseases and Hypertension, School of Medicine and Health Sciences, The George Washington University, Washington, DC, USA.
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15
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Fatoba O, Itokazu T, Yamashita T. Microglia as therapeutic target in central nervous system disorders. J Pharmacol Sci 2020; 144:102-118. [PMID: 32921391 DOI: 10.1016/j.jphs.2020.07.004] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Revised: 05/19/2020] [Accepted: 07/07/2020] [Indexed: 12/17/2022] Open
Abstract
Chronic microglial activation is associated with the pathogenesis of several CNS disorders. Microglia show phenotypic diversity and functional complexity in diseased CNS. Thus, understanding the pathology-specific heterogeneity of microglial behavior is crucial for the future development of microglia-modulating therapy for variety of CNS disorders. This review summarizes up-to-date knowledge on how microglia contribute to CNS homeostasis during development and throughout adulthood. We discuss the heterogeneity of microglial phenotypes in the context of CNS disorders with an emphasis on neurodegenerative diseases, demyelinating diseases, CNS trauma, and epilepsy. We conclude this review with a discussion about the disease-specific heterogeneity of microglial function and how it could be exploited for therapeutic intervention.
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Affiliation(s)
- Oluwaseun Fatoba
- Department of Molecular Neuroscience, Graduate School of Medicine, Osaka University, 2-2 Yamadaoka, Suita, Osaka 565-0871, Japan; WPI-Immunology Frontier Research Center, Osaka University, 3-1 Yamadaoka, Suita, Osaka 565-0871, Japan.
| | - Takahide Itokazu
- Department of Molecular Neuroscience, Graduate School of Medicine, Osaka University, 2-2 Yamadaoka, Suita, Osaka 565-0871, Japan; Department of Neuro-Medical Science, Graduate School of Medicine, Osaka University, 2-2 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Toshihide Yamashita
- Department of Molecular Neuroscience, Graduate School of Medicine, Osaka University, 2-2 Yamadaoka, Suita, Osaka 565-0871, Japan; WPI-Immunology Frontier Research Center, Osaka University, 3-1 Yamadaoka, Suita, Osaka 565-0871, Japan; Department of Neuro-Medical Science, Graduate School of Medicine, Osaka University, 2-2 Yamadaoka, Suita, Osaka 565-0871, Japan.
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16
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Selective vulnerability in α-synucleinopathies. Acta Neuropathol 2019; 138:681-704. [PMID: 31006067 PMCID: PMC6800835 DOI: 10.1007/s00401-019-02010-2] [Citation(s) in RCA: 51] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2018] [Revised: 03/13/2019] [Accepted: 04/05/2019] [Indexed: 12/11/2022]
Abstract
Parkinson's disease, dementia with Lewy bodies, and multiple system atrophy are neurodegenerative disorders resulting in progressive motor/cognitive deficits among other symptoms. They are characterised by stereotypical brain cell loss accompanied by the formation of proteinaceous aggregations of the protein α-synuclein (α-syn), being, therefore, termed α-synucleinopathies. Although the presence of α-syn inclusions is a common hallmark of these disorders, the exact nature of the deposited protein is specific to each disease. Different neuroanatomical regions and cellular populations manifest a differential vulnerability to the appearance of protein deposits, cell dysfunction, and cell death, leading to phenotypic diversity. The present review describes the multiple factors that contribute to the selective vulnerability in α-synucleinopathies. We explore the intrinsic cellular properties in the affected regions, including the physiological and pathophysiological roles of endogenous α-syn, the metabolic and genetic build-up of the cells and their connectivity. These factors converge with the variability of the α-syn conformational strains and their spreading capacity to dictate the phenotypic diversity and regional vulnerability of each disease. Finally, we describe the exogenous and environmental factors that potentially contribute by igniting and modulating the differential pathology in α-synucleinopathies. In conclusion, we think that it is the confluence of this disruption of the cellular metabolic state and α-syn structural equilibrium through the anatomical connectivity which appears to initiate cascades of pathological processes triggered by genetic, environmental, or stochastic events that result in the "death by a thousand cuts" profile of α-synucleinopathies.
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17
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Leandrou E, Emmanouilidou E, Vekrellis K. Voltage-Gated Calcium Channels and α-Synuclein: Implications in Parkinson's Disease. Front Mol Neurosci 2019; 12:237. [PMID: 31649506 PMCID: PMC6794345 DOI: 10.3389/fnmol.2019.00237] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2019] [Accepted: 09/17/2019] [Indexed: 12/15/2022] Open
Abstract
Alpha-synuclein (α-syn) is biochemically and genetically linked to Parkinson's disease (PD) and other synucleinopathies. It is now widely accepted that α-syn can be released in the extracellular space, even though the mechanism of its release is still unclear. In addition, pathology-related aggregated species of α-syn have been shown to propagate between neurons in synaptically connected areas of the brain thereby assisting the spreading of pathology in healthy neighboring neuronal cells. In neurons, calcium channels are key signaling elements that modulate the release of bioactive molecules (hormones, proteins, and neurotransmitters) through calcium sensing. Such calcium sensing activity is determined by the distinct biophysical and pharmacological properties and the ability of calcium channels to interact with other modulatory proteins. Although the function of extracellular α-syn is currently unknown, previous work suggested the presence of a calcium-dependent mechanism for α-syn secretion both in vitro, in neuronal cells in culture, and also in vivo, in the context of a trans-neuronal network in brain. Mechanisms regulating extracellular α-syn levels may be of particular importance as they could represent novel therapeutic targets. We discuss here how calcium channel activity may contribute to α-syn aggregation and secretion as a pathway to disease progression in synucleinopathies.
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Affiliation(s)
- Emmanouela Leandrou
- Center for Basic Research, Biomedical Research Foundation Academy of Athens, Athens, Greece
| | - Evangelia Emmanouilidou
- Center for Basic Research, Biomedical Research Foundation Academy of Athens, Athens, Greece.,Laboratory of Biochemistry, Department of Chemistry, National and Kapodistrian University of Athens, Athens, Greece
| | - Kostas Vekrellis
- Center for Basic Research, Biomedical Research Foundation Academy of Athens, Athens, Greece
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18
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α-Synuclein 2.0 — Moving towards Cell Type Specific Pathophysiology. Neuroscience 2019; 412:248-256. [DOI: 10.1016/j.neuroscience.2019.06.005] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Revised: 06/04/2019] [Accepted: 06/05/2019] [Indexed: 12/17/2022]
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19
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Foffani G, Obeso JA. A Cortical Pathogenic Theory of Parkinson's Disease. Neuron 2019; 99:1116-1128. [PMID: 30236282 DOI: 10.1016/j.neuron.2018.07.028] [Citation(s) in RCA: 93] [Impact Index Per Article: 18.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2018] [Revised: 06/14/2018] [Accepted: 07/17/2018] [Indexed: 01/17/2023]
Abstract
In Parkinson's disease, the progressive neurodegeneration of nigrostriatal dopaminergic neurons in the substantia nigra pars compacta (SNc) is associated with classic motor features, which typically have a focal onset. Since a defined somatotopic arrangement in the SNc has not been recognized, this focal motor onset is unexplained and hardly justified by current pathogenic theories of bottom-up disease progression (Braak's hypothesis, prionopathy). Here we propose that corticostriatal activity may represent a critical somatotopic "stressor" for nigrostriatal terminals, ultimately driving retrograde nigrostriatal degeneration and leading to focal motor onset and progression of Parkinson's disease. As a pathogenic mechanism, corticostriatal activity may promote secretion of striatal extracellular alpha-synuclein, favoring its pathological aggregation at vulnerable dopaminergic synapses. A similar pathogenic process may occur at corticofugal projections to the medulla oblongata and other vulnerable structures, thereby contributing to the bottom-up progression of Lewy pathology. This cortical pathogenesis may co-exist with bottom-up mechanisms, adding an integrative top-down perspective to the quest for the factors that impinge upon the vulnerability of dopaminergic cells in the onset and progression of Parkinson's disease.
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Affiliation(s)
- Guglielmo Foffani
- CINAC, Hospital Universitario HM Puerta del Sur, Móstoles, Universidad CEU-San Pablo, Madrid, Spain; Hospital Nacional de Parapléjicos, Toledo, Spain.
| | - José A Obeso
- CINAC, Hospital Universitario HM Puerta del Sur, Móstoles, Universidad CEU-San Pablo, Madrid, Spain; CIBERNED, Instituto de Salud Carlos III, Madrid, Spain.
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20
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SerThr-PhosphoProteome of Brain from Aged PINK1-KO+A53T-SNCA Mice Reveals pT1928-MAP1B and pS3781-ANK2 Deficits, as Hub between Autophagy and Synapse Changes. Int J Mol Sci 2019; 20:ijms20133284. [PMID: 31277379 PMCID: PMC6651490 DOI: 10.3390/ijms20133284] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Revised: 06/30/2019] [Accepted: 07/02/2019] [Indexed: 02/08/2023] Open
Abstract
Hereditary Parkinson’s disease (PD) can be triggered by an autosomal dominant overdose of alpha-Synuclein (SNCA) as stressor or the autosomal recessive deficiency of PINK1 Serine/Threonine-phosphorylation activity as stress-response. We demonstrated the combination of PINK1-knockout with overexpression of SNCAA53T in double mutant (DM) mice to exacerbate locomotor deficits and to reduce lifespan. To survey posttranslational modifications of proteins underlying the pathology, brain hemispheres of old DM mice underwent quantitative label-free global proteomic mass spectrometry, focused on Ser/Thr-phosphorylations. As an exceptionally strong effect, we detected >300-fold reductions of phosphoThr1928 in MAP1B, a microtubule-associated protein, and a similar reduction of phosphoSer3781 in ANK2, an interactor of microtubules. MAP1B depletion is known to trigger perturbations of microtubular mitochondria trafficking, neurite extension, and synaptic function, so it was noteworthy that relevantly decreased phosphorylation was also detected for other microtubule and microfilament factors, namely MAP2S1801, MARK1S394, MAP1AT1794, KIF1AS1537, 4.1NS541, 4.1GS86, and ADD2S528. While the MAP1B heavy chain supports regeneration and growth cones, its light chain assists DAPK1-mediated autophagy. Interestingly, relevant phosphorylation decreases of DAPK2S299, VPS13DS2429, and VPS13CS2480 in the DM brain affected regulators of autophagy, which are implicated in PD. Overall, significant downregulations were enriched for PFAM C2 domains, other kinases, and synaptic transmission factors upon automated bioinformatics, while upregulations were not enriched for selective motifs or pathways. Validation experiments confirmed the change of LC3 processing as reflection of excessive autophagy in DM brain, and dependence of ANK2/MAP1B expression on PINK1 levels. Our new data provide independent confirmation in a mouse model with combined PARK1/PARK4/PARK6 pathology that MAP1B/ANK2 phosphorylation events are implicated in Parkinsonian neurodegeneration. These findings expand on previous observations in Drosophila melanogaster that the MAP1B ortholog futsch in the presynapse is a primary target of the PARK8 protein LRRK2, and on a report that MAP1B is a component of the pathological Lewy body aggregates in PD patient brains. Similarly, ANK2 gene locus variants are associated with the risk of PD, ANK2 interacts with PINK1/Parkin-target proteins such as MIRO1 or ATP1A2, and ANK2-derived peptides are potent inhibitors of autophagy.
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21
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Marvian AT, Koss DJ, Aliakbari F, Morshedi D, Outeiro TF. In vitro models of synucleinopathies: informing on molecular mechanisms and protective strategies. J Neurochem 2019; 150:535-565. [PMID: 31004503 DOI: 10.1111/jnc.14707] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2019] [Revised: 04/05/2019] [Accepted: 04/12/2019] [Indexed: 02/06/2023]
Abstract
Alpha-synuclein (α-Syn) is a central player in Parkinson's disease (PD) and in a spectrum of neurodegenerative diseases collectively known as synucleinopathies. The protein was first associated with PD just over 20 years ago, when it was found to (i) be a major component of Lewy bodies and (ii) to be also associated with familial forms of PD. The characterization of α-Syn pathology has been achieved through postmortem studies of human brains. However, the identification of toxic mechanisms associated with α-Syn was only achieved through the use of experimental models. In vitro models are highly accessible, enable relatively rapid studies, and have been extensively employed to address α-Syn-associated neurodegeneration. Given the diversity of models used and the outcomes of the studies, a cumulative and comprehensive perspective emerges as indispensable to pave the way for further investigations. Here, we subdivided in vitro models of α-Syn pathology into three major types: (i) models simulating α-Syn fibrillization and the formation of different aggregated structures in vitro, (ii) models based on the intracellular expression of α-Syn, reporting on pathogenic conditions and cellular dysfunctions induced, and (iii) models using extracellular treatment with α-Syn aggregated species, reporting on sites of interaction and their downstream consequences. In summary, we review the underlying molecular mechanisms discovered and categorize protective strategies, in order to pave the way for future studies and the identification of effective therapeutic strategies. This article is part of the Special Issue "Synuclein".
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Affiliation(s)
- Amir Tayaranian Marvian
- Department of Neurology, School of Medicine, Technical University of Munich, Munich, Germany.,Department of Translational Neurodegeneration, German Center for Neurodegenerative Diseases (DZNE), Munich, Germany
| | - David J Koss
- Institute of Neuroscience, The Medical School, Newcastle University, Newcastle Upon Tyne, UK
| | - Farhang Aliakbari
- Department of Industrial and Environmental Biotechnology, National Institute of Genetic Engineering and Biotechnology, Tehran, Iran.,Department of Experimental Neurodegeneration, Center for Biostructural Imaging of Neurodegeneration, Göttingen, Germany
| | - Dina Morshedi
- Department of Industrial and Environmental Biotechnology, National Institute of Genetic Engineering and Biotechnology, Tehran, Iran
| | - Tiago Fleming Outeiro
- Institute of Neuroscience, The Medical School, Newcastle University, Newcastle Upon Tyne, UK.,Department of Experimental Neurodegeneration, Center for Biostructural Imaging of Neurodegeneration, Göttingen, Germany.,University Medical Center Göttingen, Göttingen, Germany.,Max Planck Institute for Experimental Medicine, Göttingen, Germany
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22
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Lehtonen Š, Sonninen TM, Wojciechowski S, Goldsteins G, Koistinaho J. Dysfunction of Cellular Proteostasis in Parkinson's Disease. Front Neurosci 2019; 13:457. [PMID: 31133790 PMCID: PMC6524622 DOI: 10.3389/fnins.2019.00457] [Citation(s) in RCA: 80] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2019] [Accepted: 04/23/2019] [Indexed: 12/15/2022] Open
Abstract
Despite decades of research, current therapeutic interventions for Parkinson’s disease (PD) are insufficient as they fail to modify disease progression by ameliorating the underlying pathology. Cellular proteostasis (protein homeostasis) is an essential factor in maintaining a persistent environment for neuronal activity. Proteostasis is ensured by mechanisms including regulation of protein translation, chaperone-assisted protein folding and protein degradation pathways. It is generally accepted that deficits in proteostasis are linked to various neurodegenerative diseases including PD. While the proteasome fails to degrade large protein aggregates, particularly alpha-synuclein (α-SYN) in PD, drug-induced activation of autophagy can efficiently remove aggregates and prevent degeneration of dopaminergic (DA) neurons. Therefore, maintenance of these mechanisms is essential to preserve all cellular functions relying on a correctly folded proteome. The correlations between endoplasmic reticulum (ER) stress and the unfolded protein response (UPR) that aims to restore proteostasis within the secretory pathway are well-established. However, while mild insults increase the activity of chaperones, prolonged cell stress, or insufficient adaptive response causes cell death. Modulating the activity of molecular chaperones, such as protein disulfide isomerase which assists refolding and contributes to the removal of unfolded proteins, and their associated pathways may offer a new approach for disease-modifying treatment. Here, we summarize some of the key concepts and emerging ideas on the relation of protein aggregation and imbalanced proteostasis with an emphasis on PD as our area of main expertise. Furthermore, we discuss recent insights into the strategies for reducing the toxic effects of protein unfolding in PD by targeting the ER UPR pathway.
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Affiliation(s)
- Šárka Lehtonen
- A.I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland.,Neuroscience Center, Helsinki Institute of Life Science, University of Helsinki, Helsinki, Finland
| | - Tuuli-Maria Sonninen
- A.I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland
| | - Sara Wojciechowski
- A.I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland
| | - Gundars Goldsteins
- A.I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland
| | - Jari Koistinaho
- A.I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland.,Neuroscience Center, Helsinki Institute of Life Science, University of Helsinki, Helsinki, Finland
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23
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Petrov AM, Mast N, Li Y, Pikuleva IA. The key genes, phosphoproteins, processes, and pathways affected by efavirenz-activated CYP46A1 in the amyloid-decreasing paradigm of efavirenz treatment. FASEB J 2019; 33:8782-8798. [PMID: 31063705 DOI: 10.1096/fj.201900092r] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Efavirenz (EFV) is an anti-HIV drug, and cytochrome P450 46A1 (CYP46A1) is the major brain cholesterol hydroxylase. Previously, we discovered that EFV activates CYP46A1 and improves behavioral performance in 5XFAD mice, an Alzheimer's disease model. Herein, the unbiased omics and other approaches were used to study 5XFAD mice in the amyloid-decreasing paradigm of CYP46A1 activation by EFV. These approaches revealed increases in the brain levels of postsynaptic density protein 95, gephyrin, synaptophysin, synapsin, glial fibrillary acidic protein, and CYP46A1 and documented altered expression and phosphorylation of 66 genes and 77 proteins, respectively. The data obtained pointed to EFV effects at the synaptic level, plasmin-depended amyloid clearance, inflammation and microglia phenotype, oxidative stress and cellular hypoxia, autophagy and ubiquitin-proteasome systems as well as apoptosis. These effects could be realized in part via changes in the Ca2+-, small GTPase, and catenin signaling. A model is proposed, in which CYP46A1-dependent lipid raft rearrangement and subsequent decrease of protein phosphorylation are central in EFV effects and explain behavioral improvements in EFV-treated 5XFAD mice.-Petrov, A. M., Mast, N., Li, Y., Pikuleva, I. A. The key genes, phosphoproteins, processes, and pathways affected by efavirenz-activated CYP46A1 in the amyloid-decreasing paradigm of efavirenz treatment.
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Affiliation(s)
- Alexey M Petrov
- Department of Ophthalmology and Visual Sciences, Case Western Reserve University, Cleveland, Ohio, USA
| | - Natalia Mast
- Department of Ophthalmology and Visual Sciences, Case Western Reserve University, Cleveland, Ohio, USA
| | - Yong Li
- Department of Ophthalmology and Visual Sciences, Case Western Reserve University, Cleveland, Ohio, USA
| | - Irina A Pikuleva
- Department of Ophthalmology and Visual Sciences, Case Western Reserve University, Cleveland, Ohio, USA
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24
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Catoni C, Calì T, Brini M. Calcium, Dopamine and Neuronal Calcium Sensor 1: Their Contribution to Parkinson's Disease. Front Mol Neurosci 2019; 12:55. [PMID: 30967759 PMCID: PMC6440390 DOI: 10.3389/fnmol.2019.00055] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2018] [Accepted: 02/14/2019] [Indexed: 01/11/2023] Open
Abstract
Parkinson’s disease (PD) is a debilitating neurodegenerative disorder characterized by loss of dopaminergic neurons in the substantia nigra pars compacta. The causes of PD in humans are still unknown, although metabolic characteristics of the neurons affected by the disease have been implicated in their selective susceptibility. Mitochondrial dysfunction and proteostatic stress are recognized to be important in the pathogenesis of both familial and sporadic PD, and they both culminate in bioenergetic deficits. Exposure to calcium overload has recently emerged as a key determinant, and pharmacological treatment that inhibits Ca2+ entry diminishes neuronal damage in chemical models of PD. In this review, we first introduce general concepts on neuronal Ca2+ signaling and then summarize the current knowledge on fundamental properties of substantia nigra pars compacta dopaminergic neurons, on the role of the interplay between Ca2+ and dopamine signaling in neuronal activity and susceptibility to cell death. We also discuss the possible involvement of a “neglected” player, the Neuronal Calcium Sensor-1 (NCS-1), which has been shown to participate to dopaminergic signaling by regulating dopamine dependent receptor desensitization in normal brain but, data supporting a direct role in PD pathogenesis are still missing. However, it is intriguing to speculate that the Ca2+-dependent modulation of NCS-1 activity could eventually counteract dopaminergic neurons degeneration.
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Affiliation(s)
| | - Tito Calì
- Department of Biomedical Sciences, University of Padova, Padua, Italy
| | - Marisa Brini
- Department of Biology, University of Padova, Padua, Italy
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Sgobio C, Sun L, Ding J, Herms J, Lovinger DM, Cai H. Unbalanced calcium channel activity underlies selective vulnerability of nigrostriatal dopaminergic terminals in Parkinsonian mice. Sci Rep 2019; 9:4857. [PMID: 30890737 PMCID: PMC6425036 DOI: 10.1038/s41598-019-41091-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2018] [Accepted: 02/18/2019] [Indexed: 11/23/2022] Open
Abstract
Dopamine (DA) release in striatum is functionally segregated across a dorsolateral/ventromedial axis. Interestingly, nigrostriatal DA signaling disruption in Parkinson's disease (PD) preferentially affects the dorsolateral striatum. The relationship between afferent presynaptic calcium transients (PreCaTs) in DA terminals and DA release in dorsolateral (Caudato-Putamen, DLS) and ventromedial (Nucleus Accumbens Shell, VS) striatal subregions was examined by ex vivo real-time dual-recording in conditional transgenic mice expressing the calcium indicator protein GCaMP3. In DLS, minimal increases in cytosolic calcium trigger steep DA release while PreCaTs and DA release in VS both were proportional to the number of pulses in burst stimulation. Co-expressing α-synuclein with the Parkinson's disease (PD)-associated A53T mutation and GCaMP3 in midbrain DA neurons revealed augmented cytosolic steady state and activity-dependent intra-terminal calcium levels preferentially in DLS, as well as hyperactivation and enhanced expression of N-type calcium channels. Thus, unbalanced calcium channel activity is a presynaptic mechanism to consider in the multifaceted pathogenic pathways of progressive neurodegeneration.
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Affiliation(s)
- Carmelo Sgobio
- Transgenic Section, Laboratory of Neurogenetics, National Institute on Aging, National Institutes of Health, Bethesda, MD, 20892, USA
- Translational research division, German Center for Neurodegenerative Diseases (DZNE), Munich, 81377, Germany
| | - Lixin Sun
- Transgenic Section, Laboratory of Neurogenetics, National Institute on Aging, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Jinhui Ding
- Computational Biology Group, Laboratory of Neurogenetics, National Institute on Aging, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Jochen Herms
- Translational research division, German Center for Neurodegenerative Diseases (DZNE), Munich, 81377, Germany
- Center for Neuropathology and Prion Research, Ludwig-Maximilians-Universität München, Munich, 81377, Germany
| | - David M Lovinger
- Laboratory for Integrative Neuroscience, Section on Synaptic Pharmacology, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Rockville, MD, 20852, USA.
| | - Huaibin Cai
- Transgenic Section, Laboratory of Neurogenetics, National Institute on Aging, National Institutes of Health, Bethesda, MD, 20892, USA.
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Modulation of Ca v2.3 channels by unconjugated bilirubin (UCB) - Candidate mechanism for UCB-induced neuromodulation and neurotoxicity. Mol Cell Neurosci 2019; 96:35-46. [PMID: 30877033 DOI: 10.1016/j.mcn.2019.03.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2018] [Revised: 12/15/2018] [Accepted: 03/10/2019] [Indexed: 11/23/2022] Open
Abstract
Elevated levels of unbound unconjugated bilirubin (UCB) can lead to bilirubin encephalopathy and kernicterus. In spite of a large number of studies demonstrating UCB-induced changes in central neurotransmission, it is still unclear whether these effects involve alterations in the function of specific ion channels. To assess how different UCB concentrations and UCB:albumin (U/A) molar ratios affect neuronal R-type voltage-gated Ca2+ channels, we evaluated their effects on whole-cell currents through recombinant Cav2.3 + β3 channel complexes and ex-vivo electroretinograms (ERGs) from wildtype and Cav2.3-deficient mice. Our findings show that modestly elevated levels of unbound UCB (U/A = 0.5) produce subtle but significant changes in the voltage-dependence of activation and prepulse inactivation, resulting in a stimulation of currents activated by weak depolarization and inhibition at potentials on the plateau of the activation curve. Saturation of the albumin binding capacity (U/A = 1) produced additional suppression that became significant when albumin was omitted completely and might involve a complete loss of channel function. Acutely administered UCB (U/A = 0.5) has recently been shown to affect transsynaptic signaling in the isolated vertebrate retina. The present report reveals that sustained exposure of the murine retina to UCB significantly suppresses also late responses of the inner retina (b-wave) from wildtype compared to Cav2.3-deficient mice. In addition, recovery during washout was significantly more complete and faster in retinae lacking Cav2.3 channels. Together, these findings show that UCB affects cloned and native Cav2.3 channels at clinically relevant U/A molar ratios and indicate that supersaturation of albumin is not required for modulation but associated with a loss of channel functional that could contribute to chronic neuronal dysfunction.
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Cholesterol and the Safety Factor for Neuromuscular Transmission. Int J Mol Sci 2019; 20:ijms20051046. [PMID: 30823359 PMCID: PMC6429197 DOI: 10.3390/ijms20051046] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2019] [Revised: 02/23/2019] [Accepted: 02/24/2019] [Indexed: 12/12/2022] Open
Abstract
A present review is devoted to the analysis of literature data and results of own research. Skeletal muscle neuromuscular junction is specialized to trigger the striated muscle fiber contraction in response to motor neuron activity. The safety factor at the neuromuscular junction strongly depends on a variety of pre- and postsynaptic factors. The review focuses on the crucial role of membrane cholesterol to maintain a high efficiency of neuromuscular transmission. Cholesterol metabolism in the neuromuscular junction, its role in the synaptic vesicle cycle and neurotransmitter release, endplate electrogenesis, as well as contribution of cholesterol to the synaptogenesis, synaptic integrity, and motor disorders are discussed.
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Extracellular Interactions of Alpha-Synuclein in Multiple System Atrophy. Int J Mol Sci 2018; 19:ijms19124129. [PMID: 30572656 PMCID: PMC6320782 DOI: 10.3390/ijms19124129] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2018] [Revised: 12/03/2018] [Accepted: 12/11/2018] [Indexed: 12/16/2022] Open
Abstract
Multiple system atrophy, characterized by atypical Parkinsonism, results from central nervous system (CNS) cell loss and dysfunction linked to aggregates of the normally pre-synaptic α-synuclein protein. Mostly cytoplasmic pathological α-synuclein inclusion bodies occur predominantly in oligodendrocytes in affected brain regions and there is evidence that α-synuclein released by neurons is taken up preferentially by oligodendrocytes. However, extracellular α-synuclein has also been shown to interact with other neural cell types, including astrocytes and microglia, as well as extracellular factors, mediating neuroinflammation, cell-to-cell spread and other aspects of pathogenesis. Here, we review the current evidence for how α-synuclein present in the extracellular milieu may act at the cell surface to drive components of disease progression. A more detailed understanding of the important extracellular interactions of α-synuclein with neuronal and non-neuronal cell types both in the brain and periphery may provide new therapeutic targets to modulate the disease process.
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CACHD1 is an α2δ-Like Protein That Modulates Ca V3 Voltage-Gated Calcium Channel Activity. J Neurosci 2018; 38:9186-9201. [PMID: 30181139 DOI: 10.1523/jneurosci.3572-15.2018] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2015] [Revised: 06/03/2018] [Accepted: 06/13/2018] [Indexed: 11/21/2022] Open
Abstract
The putative cache (Ca2+ channel and chemotaxis receptor) domain containing 1 (CACHD1) protein has predicted structural similarities to members of the α2δ voltage-gated Ca2+ channel auxiliary subunit family. CACHD1 mRNA and protein were highly expressed in the male mammalian CNS, in particular in the thalamus, hippocampus, and cerebellum, with a broadly similar tissue distribution to CaV3 subunits, in particular CaV3.1. In expression studies, CACHD1 increased cell-surface localization of CaV3.1, and these proteins were in close proximity at the cell surface, consistent with the formation of CACHD1-CaV3.1 complexes. In functional electrophysiological studies, coexpression of human CACHD1 with CaV3.1, CaV3.2, and CaV3.3 caused a significant increase in peak current density and corresponding increases in maximal conductance. By contrast, α2δ-1 had no effect on peak current density or maximal conductance in CaV3.1, CaV3.2, or CaV3.3. A comparison of CACHD1-mediated increases in CaV3.1 current density and gating currents revealed an increase in channel open probability. In hippocampal neurons from male and female embryonic day 19 rats, CACHD1 overexpression increased CaV3-mediated action potential firing frequency and neuronal excitability. These data suggest that CACHD1 is structurally an α2δ-like protein that functionally modulates CaV3 voltage-gated calcium channel activity.SIGNIFICANCE STATEMENT This is the first study to characterize the Ca2+ channel and chemotaxis receptor domain containing 1 (CACHD1) protein. CACHD1 is widely expressed in the CNS, in particular in the thalamus, hippocampus, and cerebellum. CACHD1 distribution is similar to that of low voltage-activated (CaV3, T-type) calcium channels, in particular to CaV3.1, a protein that regulates neuronal excitability and is a potential therapeutic target in conditions such as epilepsy and pain. CACHD1 is structurally an α2δ-like protein that functionally increases CaV3 calcium current. CACHD1 increases the presence of CaV3.1 at the cell surface, forms complexes with CaV3.1 at the cell surface, and causes an increase in channel open probability. In hippocampal neurons, CACHD1 causes increases in neuronal firing. Thus, CACHD1 represents a novel protein that modulates CaV3 activity.
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Lai B, Feng B, Che M, Wang L, Cai S, Huang M, Gu H, Jiang B, Ling E, Li M, Zeng X, Zeng Y. A Modular Assembly of Spinal Cord-Like Tissue Allows Targeted Tissue Repair in the Transected Spinal Cord. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2018; 5:1800261. [PMID: 30250785 PMCID: PMC6145267 DOI: 10.1002/advs.201800261] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2018] [Revised: 06/08/2018] [Indexed: 05/02/2023]
Abstract
Tissue engineering-based neural construction holds promise in providing organoids with defined differentiation and therapeutic potentials. Here, a bioengineered transplantable spinal cord-like tissue (SCLT) is assembled in vitro by simulating the white matter and gray matter composition of the spinal cord using neural stem cell-based tissue engineering technique. Whether the organoid would execute targeted repair in injured spinal cord is evaluated. The integrated SCLT, assembled by white matter-like tissue (WMLT) module and gray matter-like tissue (GMLT) module, shares architectural, phenotypic, and functional similarities to the adult rat spinal cord. Organotypic coculturing with the dorsal root ganglion or muscle cells shows that the SCLT embraces spinal cord organogenesis potentials to establish connections with the targets, respectively. Transplantation of the SCLT into the transected spinal cord results in a significant motor function recovery of the paralyzed hind limbs in rats. Additionally, targeted spinal cord tissue repair is achieved by the modular design of SCLT, as evidenced by an increased remyelination in the WMLT area and an enlarged innervation in the GMLT area. More importantly, the pro-regeneration milieu facilitates the formation of a neuronal relay by the donor neurons, allowing the conduction of descending and ascending neural inputs.
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Affiliation(s)
- Bi‐Qin Lai
- Key Laboratory for Stem Cells and Tissue Engineering (Sun Yat‐sen University)Ministry of EducationGuangzhou510080China
- Department of Histology and EmbryologyZhongshan School of MedicineSun Yat‐sen UniversityGuangzhou510080China
- Co‐Innovation Center of NeuroregenerationNantong UniversityNantong226001China
| | - Bo Feng
- Key Laboratory for Stem Cells and Tissue Engineering (Sun Yat‐sen University)Ministry of EducationGuangzhou510080China
| | - Ming‐Tian Che
- Key Laboratory for Stem Cells and Tissue Engineering (Sun Yat‐sen University)Ministry of EducationGuangzhou510080China
| | - Lai‐Jian Wang
- Guangdong Provincial Key Laboratory of Brain Function and DiseaseZhongshan School of MedicineSun Yat‐sen UniversityGuangzhou510080China
| | - Song Cai
- Department of Human AnatomyZhongshan School of MedicineSun Yat‐sen UniversityGuangzhou510080China
| | - Meng‐Yao Huang
- Guangdong Provincial Key Laboratory of Brain Function and DiseaseZhongshan School of MedicineSun Yat‐sen UniversityGuangzhou510080China
| | - Huai‐Yu Gu
- Department of Human AnatomyZhongshan School of MedicineSun Yat‐sen UniversityGuangzhou510080China
| | - Bing Jiang
- Guangdong Provincial Key Laboratory of Brain Function and DiseaseZhongshan School of MedicineSun Yat‐sen UniversityGuangzhou510080China
| | - Eng‐Ang Ling
- Department of AnatomyYong Loo Lin School of MedicineNational University of SingaporeSingapore117594Singapore
| | - Meng Li
- Neuroscience and Mental Health Research InstituteSchool of MedicineCardiff UniversityCardiffCF24 4HQUK
| | - Xiang Zeng
- Key Laboratory for Stem Cells and Tissue Engineering (Sun Yat‐sen University)Ministry of EducationGuangzhou510080China
- Department of Histology and EmbryologyZhongshan School of MedicineSun Yat‐sen UniversityGuangzhou510080China
- Institute of Spinal Cord InjurySun Yat‐sen UniversityGuangzhou510120China
| | - Yuan‐Shan Zeng
- Key Laboratory for Stem Cells and Tissue Engineering (Sun Yat‐sen University)Ministry of EducationGuangzhou510080China
- Department of Histology and EmbryologyZhongshan School of MedicineSun Yat‐sen UniversityGuangzhou510080China
- Co‐Innovation Center of NeuroregenerationNantong UniversityNantong226001China
- Guangdong Provincial Key Laboratory of Brain Function and DiseaseZhongshan School of MedicineSun Yat‐sen UniversityGuangzhou510080China
- Institute of Spinal Cord InjurySun Yat‐sen UniversityGuangzhou510120China
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Post MR, Lieberman OJ, Mosharov EV. Can Interactions Between α-Synuclein, Dopamine and Calcium Explain Selective Neurodegeneration in Parkinson's Disease? Front Neurosci 2018; 12:161. [PMID: 29593491 PMCID: PMC5861202 DOI: 10.3389/fnins.2018.00161] [Citation(s) in RCA: 52] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2017] [Accepted: 02/27/2018] [Indexed: 12/11/2022] Open
Abstract
Several lines of evidence place alpha-synuclein (aSyn) at the center of Parkinson's disease (PD) etiology, but it is still unclear why overexpression or mutated forms of this protein affect some neuronal populations more than others. Susceptible neuronal populations in PD, dopaminergic neurons of the substantia nigra pars compacta (SNpc) and the locus coeruleus (LC), are distinguished by relatively high cytoplasmic concentrations of dopamine and calcium ions. Here we review the evidence for the multi-hit hypothesis of neurodegeneration, including recent papers that demonstrate synergistic interactions between aSyn, calcium ions and dopamine that may lead to imbalanced protein turnover and selective susceptibility of these neurons. We conclude that decreasing the levels of any one of these toxicity mediators can be beneficial for the survival of SNpc and LC neurons, providing multiple opportunities for targeted drug interventions aimed at modifying the course of PD.
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Affiliation(s)
- Michael R Post
- Departments of Psychiatry and Neurology, New York State Psychiatric Institute, Columbia University Medical Center, New York, NY, United States
| | - Ori J Lieberman
- Departments of Psychiatry and Neurology, New York State Psychiatric Institute, Columbia University Medical Center, New York, NY, United States
| | - Eugene V Mosharov
- Departments of Psychiatry and Neurology, New York State Psychiatric Institute, Columbia University Medical Center, New York, NY, United States
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Extracellular α-synuclein levels are regulated by neuronal activity. Mol Neurodegener 2018; 13:9. [PMID: 29467003 PMCID: PMC5822605 DOI: 10.1186/s13024-018-0241-0] [Citation(s) in RCA: 94] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2017] [Accepted: 02/06/2018] [Indexed: 01/22/2023] Open
Abstract
Background α-Synuclein is a presynaptic protein abundant in the cytoplasmic compartment of neurons, whereas its presence in the extracellular space has also been observed under physiological conditions. Extracellular α-synuclein has pathological significance, exhibiting cellular toxicity and impairment of synaptic transmission. Notably, misfolded α-synuclein drives the cell-to-cell propagation of pathology via the extracellular space. However, the primary mechanism that regulates the extracellular levels of α-synuclein remains to be determined. Methods Using several mechanistically distinct methods to modulate neuronal/synaptic activities in primary neuronal culture and in vivo microdialysis, we examined the involvement of neuronal/synaptic activities on α-synuclein release. Results We demonstrate here that physiological release of endogenous α-synuclein highly depends on intrinsic neuronal activities. Elevating neuronal activity rapidly increased, while blocking activity decreased, α-synuclein release. In vivo microdialysis experiments in freely moving mice revealed that ~ 70% of extracellular α-synuclein arises from neuronal activity-dependent pathway. Selective modulation of glutamatergic neurotransmission altered extracellular α-synuclein levels, implicating this specific neuronal network in the mechanism of activity-dependent release of α-synuclein. While neuronal activity tightly regulated α-synuclein release, elevated synaptic vesicle exocytosis per se was capable to elicit α-synuclein release. We also found that extracellular α-synuclein exists as high molecular weight species. Conclusions The present study uncovers a novel regulatory pathway associated with α-synuclein release, whose dysregulation might affect various pathological actions of extracellular α-synuclein including its trans-synaptic propagation.
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Han J, Plummer J, Liu L, Byrd A, Aschner M, Erikson KM. The impact of obesity on brain iron levels and α-synuclein expression is regionally dependent. Nutr Neurosci 2017; 22:335-343. [PMID: 29034829 DOI: 10.1080/1028415x.2017.1387720] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
BACKGROUND The importance of iron homeostasis is particularly apparent in the brain, where iron deficiency results in impaired cognition and iron accumulation is associated with neurodegenerative diseases. Obesity is linked to iron deficiency systemically, but the effects of obesity on brain iron and its associated consequences, including neurodegenerative processes remain unexplored. This preliminary study examined the effect of dietary-induced obesity on brain regional iron, α-synuclein expression, and F2-isoprostane (oxidative stress marker) concentrations in selected brain regions. OBJECTIVE The objective of the study was to elucidate the vulnerability of selected brain regions (e.g. midbrain, hippocampus) to the possible process of neurodegeneration due to the altered iron content associated with obesity. METHODS Twenty-one-day-old male C57BL/6J mice were fed with a high-fat diet (60% kcal from fat) or a control-fat diet (10% kcal from fat) for 20 weeks. Brain samples were collected and dissected into hippocampus, midbrain, striatum, and thalamus regions. Iron content, ferritin H (FtH) and α-synuclein protein and mRNA expressions, and F2-isoprostane were measured in selected regions. RESULTS The results indicated that obesity caused significant differences in iron levels in the midbrain and thalamus, but not in the hippocampus or striatum, compared to control mice. Furthermore, markers of neurodegeneration (α-synuclein mRNA expression and F2-isoprostanes) were increased in the midbrain. DISCUSSION These results support previous findings that brain iron metabolism responds to environmental stress in a regionally distinct manner and suggests that alterations in brain iron metabolism due to obesity may be relevant in neurodegeneration.
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Affiliation(s)
- Jian Han
- a Department of Biology , North Carolina Agricultural and Technical State University , Greensboro , NC 27411 , USA
| | - Justin Plummer
- b Department of Nutrition , The University of North Carolina at Greensboro , Greensboro , NC 27412 , USA
| | - Lumei Liu
- a Department of Biology , North Carolina Agricultural and Technical State University , Greensboro , NC 27411 , USA
| | - Aria Byrd
- c Department of Toxicology and Cancer Biology , University of Kentucky , Lexington , KY 40536 , USA
| | - Michael Aschner
- d Department of Molecular Pharmacology , Albert Einstein School of Medicine , Bronx , NY 10461 , USA
| | - Keith M Erikson
- b Department of Nutrition , The University of North Carolina at Greensboro , Greensboro , NC 27412 , USA
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Florenzano F, Veronica C, Ciasca G, Ciotti MT, Pittaluga A, Olivero G, Feligioni M, Iannuzzi F, Latina V, Maria Sciacca MF, Sinopoli A, Milardi D, Pappalardo G, Marco DS, Papi M, Atlante A, Bobba A, Borreca A, Calissano P, Amadoro G. Extracellular truncated tau causes early presynaptic dysfunction associated with Alzheimer's disease and other tauopathies. Oncotarget 2017; 8:64745-64778. [PMID: 29029390 PMCID: PMC5630290 DOI: 10.18632/oncotarget.17371] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2017] [Accepted: 04/11/2017] [Indexed: 12/14/2022] Open
Abstract
The largest part of tau secreted from AD nerve terminals and released in cerebral spinal fluid (CSF) is C-terminally truncated, soluble and unaggregated supporting potential extracellular role(s) of NH2 -derived fragments of protein on synaptic dysfunction underlying neurodegenerative tauopathies, including Alzheimer's disease (AD). Here we show that sub-toxic doses of extracellular-applied human NH2 tau 26-44 (aka NH 2 htau) -which is the minimal active moiety of neurotoxic 20-22kDa peptide accumulating in vivo at AD synapses and secreted into parenchyma- acutely provokes presynaptic deficit in K+ -evoked glutamate release on hippocampal synaptosomes along with alteration in local Ca2+ dynamics. Neuritic dystrophy, microtubules breakdown, deregulation in presynaptic proteins and loss of mitochondria located at nerve endings are detected in hippocampal cultures only after prolonged exposure to NH 2 htau. The specificity of these biological effects is supported by the lack of any significant change, either on neuronal activity or on cellular integrity, shown by administration of its reverse sequence counterpart which behaves as an inactive control, likely due to a poor conformational flexibility which makes it unable to dynamically perturb biomembrane-like environments. Our results demonstrate that one of the AD-relevant, soluble and secreted N-terminally truncated tau forms can early contribute to pathology outside of neurons causing alterations in synaptic activity at presynaptic level, independently of overt neurodegeneration.
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Affiliation(s)
| | | | - Gabriele Ciasca
- Institute of Physics, Catholic University of the Sacred Heart, Largo F Vito 1, Rome, Italy
| | - Maria Teresa Ciotti
- Institute of Cellular Biology and Neuroscience, CNR, IRCSS Santa Lucia Foundation, Rome, Italy
| | - Anna Pittaluga
- Department of Pharmacy, Pharmacology and Toxicology Section, University of Genoa, Genoa, Viale Cembrano, Italy
| | - Gunedalina Olivero
- Department of Pharmacy, Pharmacology and Toxicology Section, University of Genoa, Genoa, Viale Cembrano, Italy
| | - Marco Feligioni
- European Brain Research Institute, Rome, Italy
- Department of Neurorehabilitation Sciences, Casa Cura Policlinico, Milan, Italy
| | | | | | | | | | - Danilo Milardi
- Institute of Biostructures and Bioimaging, CNR, Catania, Italy
| | | | - De Spirito Marco
- Institute of Physics, Catholic University of the Sacred Heart, Largo F Vito 1, Rome, Italy
| | - Massimiliano Papi
- Institute of Physics, Catholic University of the Sacred Heart, Largo F Vito 1, Rome, Italy
| | - Anna Atlante
- Institute of Biomembranes and Bioenergetics, CNR, Bari, Italy
- Center of Excellence for Biomedical Research, University of Genoa, Genoa, Viale Benedetto XV, Italy
| | - Antonella Bobba
- Institute of Biomembranes and Bioenergetics, CNR, Bari, Italy
- Center of Excellence for Biomedical Research, University of Genoa, Genoa, Viale Benedetto XV, Italy
| | - Antonella Borreca
- Institute of Cellular Biology and Neuroscience, CNR, IRCSS Santa Lucia Foundation, Rome, Italy
| | | | - Giuseppina Amadoro
- European Brain Research Institute, Rome, Italy
- Institute of Translational Pharmacology, CNR, Rome, Italy
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SUMOylation and calcium signalling: potential roles in the brain and beyond. Neuronal Signal 2017; 1:NS20160010. [PMID: 32714579 PMCID: PMC7373246 DOI: 10.1042/ns20160010] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2017] [Revised: 07/10/2017] [Accepted: 07/11/2017] [Indexed: 12/23/2022] Open
Abstract
Small ubiquitin-like modifier (SUMO) conjugation (or SUMOylation) is a post-translational protein modification implicated in alterations to protein expression, localization and function. Despite a number of nuclear roles for SUMO being well characterized, this process has only started to be explored in relation to membrane proteins, such as ion channels. Calcium ion (Ca2+) signalling is crucial for the normal functioning of cells and is also involved in the pathophysiological mechanisms underlying relevant neurological and cardiovascular diseases. Intracellular Ca2+ levels are tightly regulated; at rest, most Ca2+ is retained in organelles, such as the sarcoplasmic reticulum, or in the extracellular space, whereas depolarization triggers a series of events leading to Ca2+ entry, followed by extrusion and reuptake. The mechanisms that maintain Ca2+ homoeostasis are candidates for modulation at the post-translational level. Here, we review the effects of protein SUMOylation, including Ca2+ channels, their proteome and other proteins associated with Ca2+ signalling, on vital cellular functions, such as neurotransmission within the central nervous system (CNS) and in additional systems, most prominently here, in the cardiac system.
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Sarafian TA, Littlejohn K, Yuan S, Fernandez C, Cilluffo M, Koo BK, Whitelegge JP, Watson JB. Stimulation of synaptoneurosome glutamate release by monomeric and fibrillated α-synuclein. J Neurosci Res 2017; 95:1871-1887. [PMID: 28117497 DOI: 10.1002/jnr.24024] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2016] [Revised: 11/11/2016] [Accepted: 12/28/2016] [Indexed: 12/28/2022]
Abstract
The α-synuclein protein exists in vivo in a variety of covalently modified and aggregated forms associated with Parkinson's disease (PD) pathology. However, the specific proteoform structures involved with neuropathological disease mechanisms are not clearly defined. Since α-synuclein plays a role in presynaptic neurotransmitter release, an in vitro enzyme-based assay was developed to measure glutamate release from mouse forebrain synaptoneurosomes (SNs) enriched in synaptic endings. Glutamate measurements utilizing SNs from various mouse genotypes (WT, over-expressers, knock-outs) suggested a concentration dependence of α-synuclein on calcium/depolarization-dependent presynaptic glutamate release from forebrain terminals. In vitro reconstitution experiments with recombinant human α-synuclein proteoforms including monomers and aggregated forms (fibrils, oligomers) produced further evidence of this functional impact. Notably, brief exogenous applications of fibrillated forms of α-synuclein enhanced SN glutamate release but monomeric forms did not, suggesting preferential membrane penetration and toxicity by the aggregated forms. However, when applied to brain tissue sections just prior to homogenization, both monomeric and fibrillated forms stimulated glutamate release. Immuno-gold and transmission electron microscopy (TEM) detected exogenous fibrillated α-synuclein associated with numerous SN membranous structures including synaptic terminals. Western blots and immuno-gold TEM were consistent with SN internalization of α-synuclein. Additional studies revealed no evidence of gross disruption of SN membrane integrity or glutamate transporter function by exogenous α-synuclein. Overall excitotoxicity, due to enhanced glutamate release in the face of either overexpressed monomeric α-synuclein or extrasynaptic exposure to fibrillated α-synuclein, should be considered as a potential neuropathological pathway during the progression of PD and other synucleinopathies. © 2017 Wiley Periodicals, Inc.
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Affiliation(s)
- Theodore A Sarafian
- Department of Psychiatry and Biobehavioral Sciences, David Geffen School of Medicine, UCLA, Los Angeles, CA, USA
| | - Kaitlyn Littlejohn
- Department of Psychiatry and Biobehavioral Sciences, David Geffen School of Medicine, UCLA, Los Angeles, CA, USA
| | - Sarah Yuan
- Department of Psychiatry and Biobehavioral Sciences, David Geffen School of Medicine, UCLA, Los Angeles, CA, USA
| | - Charlene Fernandez
- Department of Psychiatry and Biobehavioral Sciences, David Geffen School of Medicine, UCLA, Los Angeles, CA, USA
| | | | - Bon-Kyung Koo
- Department of Chemistry and Biochemistry, UCLA, Los Angeles, CA, USA
| | - Julian P Whitelegge
- Department of Psychiatry and Biobehavioral Sciences, David Geffen School of Medicine, UCLA, Los Angeles, CA, USA
| | - Joseph B Watson
- Department of Psychiatry and Biobehavioral Sciences, David Geffen School of Medicine, UCLA, Los Angeles, CA, USA
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Ottolini D, Calí T, Szabò I, Brini M. Alpha-synuclein at the intracellular and the extracellular side: functional and dysfunctional implications. Biol Chem 2017; 398:77-100. [DOI: 10.1515/hsz-2016-0201] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2016] [Accepted: 08/01/2016] [Indexed: 12/16/2022]
Abstract
Abstract
Alpha-synuclein (α-syn) is an abundant neuronal protein whose physiological function, even if still not completely understood, has been consistently related to synaptic function and vesicle trafficking. A group of disorders known as synucleinopathies, among which Parkinson’s disease (PD), is deeply associated with the misfolding and aggregation of α-syn, which can give rise to proteinaceous inclusion known as Lewy bodies (LB). Proteostasis stress is a relevant aspect in these diseases and, currently, the presence of oligomeric α-syn species rather than insoluble aggregated forms, appeared to be associated with cytotoxicity. Many observations suggest that α-syn is responsible for neurodegeneration by interfering with multiple signaling pathways. α-syn protein can directly form plasma membrane channels or modify with their activity, thus altering membrane permeability to ions, abnormally associate with mitochondria and cause mitochondrial dysfunction (i.e. mitochondrial depolarization, Ca2+ dys-homeostasis, cytochrome c release) and interfere with autophagy regulation. The picture is further complicated by the fact that single point mutations, duplications and triplication in α-syn gene are linked to autosomal dominant forms of PD. In this review we discuss the multi-faced aspect of α-syn biology and address the main hypothesis at the basis of its involvement in neuronal degeneration.
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Exploring the neural mechanisms of finasteride: a proteomic analysis in the nucleus accumbens. Psychoneuroendocrinology 2016; 74:387-396. [PMID: 27750143 DOI: 10.1016/j.psyneuen.2016.10.001] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/03/2016] [Revised: 09/07/2016] [Accepted: 10/05/2016] [Indexed: 02/06/2023]
Abstract
The enzyme 5α-reductase (5αR) catalyzes the conversion of progesterone and testosterone into neuroactive steroids implicated in a wide array of behavioral functions. The prototypical 5αR inhibitor, finasteride (FIN), is clinically approved for the treatment of androgenic alopecia and benign prostatic hyperplasia. Recent evidence has shown that FIN, albeit generally well tolerated, can induce untoward psychological effects in a subset of patients; furthermore, this drug may have therapeutic efficacy for a number of different neuropsychiatric conditions, ranging from Tourette syndrome to schizophrenia. In rat models of these conditions, FIN has been shown to block the effects of dopamine receptors in the nucleus accumbens (NAcc), a key terminal of the dopamine mesolimbic system. The biological underpinnings of these effects, however, remain mostly elusive. To elucidate the neurochemical networks that may be responsible for the behavioral effects of FIN, we evaluated the proteomic profile of the NAcc following acute (100mg/kg, IP) and subchronic (7 days; 100mg/kg/day, IP) treatment with this drug, in comparison with vehicle treatment (n=5/group). Two-dimensional electrophoresis (2-DE) analysis coupled to mass spectrometry revealed significant changes in the expression of nine proteins (CRMP2, PSMD1, STX18, KCNC3, CYP255, GABRP, GABT, PRPS1, CYP2B3), which were further analyzed by ontological classification (PANTHER). These results point to a number of novel potential chemical targets of FIN, and may help elucidate the underpinnings of FIN's behavioral effects and therapeutic potential for neuropsychiatric disorders.
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Butler B, Sambo D, Khoshbouei H. Alpha-synuclein modulates dopamine neurotransmission. J Chem Neuroanat 2016; 83-84:41-49. [PMID: 27334403 DOI: 10.1016/j.jchemneu.2016.06.001] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2016] [Revised: 06/03/2016] [Accepted: 06/11/2016] [Indexed: 01/13/2023]
Abstract
Alpha-synuclein is a small, highly charged protein encoded by the synuclein or SNCA gene that is predominantly expressed in central nervous system neurons. Although its physiological function remains enigmatic, alpha-synuclein is implicated in movement disorders such as Parkinson's disease, multiple system atrophy, and in neurodegenerative diseases such as Dementia with Lewy bodies. Here we have focused on reviewing the existing literature pertaining to wild-type alpha-synuclein structure, its properties, and its potential involvement in regulation of dopamine neurotransmission.
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Affiliation(s)
- Brittany Butler
- University of Florida, Department of Neuroscience and Department of Psychiatry Gainesville, FL 32611
| | - Danielle Sambo
- University of Florida, Department of Neuroscience and Department of Psychiatry Gainesville, FL 32611
| | - Habibeh Khoshbouei
- University of Florida, Department of Neuroscience and Department of Psychiatry Gainesville, FL 32611.
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Kasimov MR, Zakyrjanova GF, Giniatullin AR, Zefirov AL, Petrov AM. Similar oxysterols may lead to opposite effects on synaptic transmission: Olesoxime versus 5α-cholestan-3-one at the frog neuromuscular junction. Biochim Biophys Acta Mol Cell Biol Lipids 2016; 1861:606-16. [PMID: 27102612 DOI: 10.1016/j.bbalip.2016.04.010] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2015] [Revised: 03/17/2016] [Accepted: 04/15/2016] [Indexed: 02/03/2023]
Abstract
Cholesterol oxidation products frequently have a high biological activity. In the present study, we have used microelectrode recording of end plate currents and FM-based optical detection of synaptic vesicle exo-endocytosis to investigate the effects of two structurally similar oxysterols, olesoxime (cholest-4-en-3-one, oxime) and 5ɑ-cholestan-3-one (5ɑCh3), on neurotransmission at the frog neuromuscular junction. Olesoxime is an exogenous, potentially neuroprotective, substance and 5ɑCh3 is an intermediate product in cholesterol metabolism, which is elevated in the case of cerebrotendinous xanthomatosis. We found that olesoxime slightly increased evoked neurotransmitter release in response to a single stimulus and significantly reduced synaptic depression during high frequency activity. The last effect was due to an increase in both the number of synaptic vesicles involved in exo-endocytosis and the rate of synaptic vesicle recycling. In contrast, 5ɑCh3 reduced evoked neurotransmitter release during the low- and high frequency synaptic activities. The depressant action of 5ɑCh3 was associated with a reduction in the number of synaptic vesicles participating in exo- and endocytosis during high frequency stimulation, without a change in rate of the synaptic vesicle recycling. Of note, olesoxime increased the staining of synaptic membranes with the B-subunit of cholera toxin and the formation of fluorescent ganglioside GM1 clusters, and decreased the fluorescence of 22-NBD-cholesterol, while 5ɑCh3 had the opposite effects, suggesting that the two oxysterols have different effects on lipid raft stability. Taken together, these data show that these two structurally similar oxysterols induce marked different changes in neuromuscular transmission which are related with the alteration in synaptic vesicle cycle.
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Affiliation(s)
- M R Kasimov
- Department of Normal Physiology, Kazan State Medical University, Kazan 420012, Russia
| | - G F Zakyrjanova
- Department of Normal Physiology, Kazan State Medical University, Kazan 420012, Russia
| | - A R Giniatullin
- Department of Normal Physiology, Kazan State Medical University, Kazan 420012, Russia
| | - A L Zefirov
- Department of Normal Physiology, Kazan State Medical University, Kazan 420012, Russia
| | - A M Petrov
- Department of Normal Physiology, Kazan State Medical University, Kazan 420012, Russia.
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Exogenous Alpha-Synuclein Alters Pre- and Post-Synaptic Activity by Fragmenting Lipid Rafts. EBioMedicine 2016; 7:191-204. [PMID: 27322472 PMCID: PMC4909369 DOI: 10.1016/j.ebiom.2016.03.038] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2015] [Revised: 02/24/2016] [Accepted: 03/24/2016] [Indexed: 12/28/2022] Open
Abstract
Alpha-synuclein (αSyn) interferes with multiple steps of synaptic activity at pre-and post-synaptic terminals, however the mechanism/s by which αSyn alters neurotransmitter release and synaptic potentiation is unclear. By atomic force microscopy we show that human αSyn, when incubated with reconstituted membrane bilayer, induces lipid rafts' fragmentation. As a consequence, ion channels and receptors are displaced from lipid rafts with consequent changes in their activity. The enhanced calcium entry leads to acute mobilization of synaptic vesicles, and exhaustion of neurotransmission at later stages. At the post-synaptic terminal, an acute increase in glutamatergic transmission, with increased density of PSD-95 puncta, is followed by disruption of the interaction between N-methyl-d-aspartate receptor (NMDAR) and PSD-95 with ensuing decrease of long term potentiation. While cholesterol loading prevents the acute effect of αSyn at the presynapse; inhibition of casein kinase 2, which appears activated by reduction of cholesterol, restores the correct localization and clustering of NMDARs. Extracellular αSyn disrupts lipid raft platforms with consequent mislocalization of several pre- and post-synaptic proteins. αSyn-driven changes in raft-partitioning of proteins blunt neurotransmission and LTP. Cholesterol loading and inhibition of CK2 restore αSyn-induced alterations of the post-synaptic density assembly.
Alpha-synuclein (αSyn), a cytosolic protein that can be released from neurons, becomes pathogenic when expressed at high levels, as in Parkinson's disease, due to multiplication of αSyn gene. We show that the mechanism responsible for the defects in synaptic vesicles mobilization and post-synaptic activity induced by extracellular αSyn is the fragmentation of lipid rafts, cholesterol-rich microdomains of the plasma membrane. Moreover restoration of lipid raft platforms and raft-partitioning of surface proteins prevents the alteration of synaptic transmission caused by exposure of neurons to αSyn.
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Samuel F, Flavin WP, Iqbal S, Pacelli C, Sri Renganathan SD, Trudeau LE, Campbell EM, Fraser PE, Tandon A. Effects of Serine 129 Phosphorylation on α-Synuclein Aggregation, Membrane Association, and Internalization. J Biol Chem 2015; 291:4374-85. [PMID: 26719332 DOI: 10.1074/jbc.m115.705095] [Citation(s) in RCA: 115] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2015] [Indexed: 02/04/2023] Open
Abstract
Although trace levels of phosphorylated α-synuclein (α-syn) are detectable in normal brains, nearly all α-syn accumulated within Lewy bodies in Parkinson disease brains is phosphorylated on serine 129 (Ser-129). The role of the phosphoserine residue and its effects on α-syn structure, function, and intracellular accumulation are poorly understood. Here, co-expression of α-syn and polo-like kinase 2 (PLK2), a kinase that targets Ser-129, was used to generate phosphorylated α-syn for biophysical and biological characterization. Misfolding and fibril formation of phosphorylated α-syn isoforms were detected earlier, although the fibrils remained phosphatase- and protease-sensitive. Membrane binding of α-syn monomers was differentially affected by phosphorylation depending on the Parkinson disease-linked mutation. WT α-syn binding to presynaptic membranes was not affected by phosphorylation, whereas A30P α-syn binding was greatly increased, and A53T α-syn was slightly lower, implicating distal effects of the carboxyl- on amino-terminal membrane binding. Endocytic vesicle-mediated internalization of pre-formed fibrils into non-neuronal cells and dopaminergic neurons matched the efficacy of α-syn membrane binding. Finally, the disruption of internalized vesicle membranes was enhanced by the phosphorylated α-syn isoforms, a potential means for misfolded extracellular or lumenal α-syn to access cytosolic α-syn. Our results suggest that the threshold for vesicle permeabilization is evident even at low levels of α-syn internalization and are relevant to therapeutic strategies to reduce intercellular propagation of α-syn misfolding.
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Affiliation(s)
- Filsy Samuel
- From the Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, Ontario M5T 2S8, Canada
| | | | - Sobia Iqbal
- From the Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, Ontario M5T 2S8, Canada
| | - Consiglia Pacelli
- the Departments of Pharmacology and Neurosciences, Central Nervous System Research Group (GRSNC), Faculty of Medicine, Université de Montréal, Québec H4T 1J4, Canada, and
| | | | - Louis-Eric Trudeau
- the Departments of Pharmacology and Neurosciences, Central Nervous System Research Group (GRSNC), Faculty of Medicine, Université de Montréal, Québec H4T 1J4, Canada, and
| | - Edward M Campbell
- the Integrative Cell Biology Program, Department of Microbiology and Immunology, Stritch School of Medicine, Loyola University Chicago, Maywood, Illinois 60153
| | - Paul E Fraser
- From the Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, Ontario M5T 2S8, Canada, the Departments of Medical Biophysics and
| | - Anurag Tandon
- From the Tanz Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, Ontario M5T 2S8, Canada, Medicine, University of Toronto, Toronto, Ontario M5T 2S8, Canada
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Tilve S, Difato F, Chieregatti E. Cofilin 1 activation prevents the defects in axon elongation and guidance induced by extracellular alpha-synuclein. Sci Rep 2015; 5:16524. [PMID: 26558842 PMCID: PMC4642265 DOI: 10.1038/srep16524] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2015] [Accepted: 10/15/2015] [Indexed: 12/20/2022] Open
Abstract
Impaired adult neurogenesis and axon traumatic injury participate in the severity of neurodegenerative diseases. Alpha-synuclein, a cytosolic protein involved in Parkinson's disease, may be released from neurons, suggesting a role for excess secreted alpha-synuclein in the onset and spread of the pathology. Here we provide evidence that long term exposure of young neurons to extracellular alpha-synuclein hampers axon elongation and growth cone turning. We show that actin turnover and the rate of movement of actin waves along the axon are altered, due to alpha-synuclein-induced inactivation of cofilin. Upon laser disruption of microfilaments, healing of axons is favored by the increased phosphorylation of cofilin, however, at later time points; the defect in neurite extension prevails, being lost the regulation of cofilin activity. Importantly, overexpression of the active form of cofilin in neurons exposed to alpha-synuclein is able to restore the movement of actin waves, physiological axon elongation and growth cone turning. Our study reveals the molecular basis of alpha-synuclein-driven deficits in growth and migration of newborn neurons, and in elongation and regeneration of adult neurons.
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Affiliation(s)
- Sharada Tilve
- Department of Neuroscience and Brain Technologies, Istituto Italiano di Tecnologia, 16163 Genoa, Italy
| | - Francesco Difato
- Department of Neuroscience and Brain Technologies, Istituto Italiano di Tecnologia, 16163 Genoa, Italy
| | - Evelina Chieregatti
- Department of Neuroscience and Brain Technologies, Istituto Italiano di Tecnologia, 16163 Genoa, Italy
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Ronzitti G, Bucci G, Stephens G, Chieregatti E. Raft-partitioning of calcium channels regulates their function. Channels (Austin) 2015; 9:169-70. [PMID: 26102507 DOI: 10.1080/19336950.2015.1063285] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
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Moratalla R, Khairnar A, Simola N, Granado N, García-Montes JR, Porceddu PF, Tizabi Y, Costa G, Morelli M. Amphetamine-related drugs neurotoxicity in humans and in experimental animals: Main mechanisms. Prog Neurobiol 2015; 155:149-170. [PMID: 26455459 DOI: 10.1016/j.pneurobio.2015.09.011] [Citation(s) in RCA: 143] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2015] [Revised: 09/04/2015] [Accepted: 09/15/2015] [Indexed: 12/13/2022]
Abstract
Amphetamine-related drugs, such as 3,4-methylenedioxymethamphetamine (MDMA) and methamphetamine (METH), are popular recreational psychostimulants. Several preclinical studies have demonstrated that, besides having the potential for abuse, amphetamine-related drugs may also elicit neurotoxic and neuroinflammatory effects. The neurotoxic potentials of MDMA and METH to dopaminergic and serotonergic neurons have been clearly demonstrated in both rodents and non-human primates. This review summarizes the species-specific cellular and molecular mechanisms involved in MDMA and METH-mediated neurotoxic and neuroinflammatory effects, along with the most important behavioral changes elicited by these substances in experimental animals and humans. Emphasis is placed on the neuropsychological and neurological consequences associated with the neuronal damage. Moreover, we point out the gap in our knowledge and the need for developing appropriate therapeutic strategies to manage the neurological problems associated with amphetamine-related drug abuse.
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Affiliation(s)
- Rosario Moratalla
- Instituto Cajal, Consejo Superior de Investigaciones Científicas, CSIC, Madrid, Spain; CIBERNED, ISCIII, Madrid, Spain.
| | - Amit Khairnar
- Applied Neuroscience Research Group, CEITEC - Central European Institute of Technology, Masaryk University, Brno, Czech Republic
| | - Nicola Simola
- Department of Biomedical Sciences, Section of Neuropsychopharmacology, University of Cagliari, Via Ospedale 72, 09124 Cagliari, Italy
| | - Noelia Granado
- Instituto Cajal, Consejo Superior de Investigaciones Científicas, CSIC, Madrid, Spain; CIBERNED, ISCIII, Madrid, Spain
| | - Jose Ruben García-Montes
- Instituto Cajal, Consejo Superior de Investigaciones Científicas, CSIC, Madrid, Spain; CIBERNED, ISCIII, Madrid, Spain
| | - Pier Francesca Porceddu
- Department of Biomedical Sciences, Section of Neuropsychopharmacology, University of Cagliari, Via Ospedale 72, 09124 Cagliari, Italy
| | - Yousef Tizabi
- Department of Pharmacology, Howard University College of Medicine, Washington, DC, USA
| | - Giulia Costa
- Department of Biomedical Sciences, Section of Neuropsychopharmacology, University of Cagliari, Via Ospedale 72, 09124 Cagliari, Italy
| | - Micaela Morelli
- Department of Biomedical Sciences, Section of Neuropsychopharmacology, University of Cagliari, Via Ospedale 72, 09124 Cagliari, Italy; Centre of Excellence for Neurobiology of Dependence, University of Cagliari, Cagliari, Italy; National Research Council (CNR), Institute of Neuroscience, Cagliari, Italy
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Villar-Piqué A, Lopes da Fonseca T, Outeiro TF. Structure, function and toxicity of alpha-synuclein: the Bermuda triangle in synucleinopathies. J Neurochem 2015; 139 Suppl 1:240-255. [PMID: 26190401 DOI: 10.1111/jnc.13249] [Citation(s) in RCA: 152] [Impact Index Per Article: 16.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2015] [Revised: 06/29/2015] [Accepted: 07/14/2015] [Indexed: 12/11/2022]
Abstract
Parkinson's disease belongs to a group of currently incurable neurodegenerative disorders characterized by the misfolding and accumulation of alpha-synuclein aggregates that are commonly known as synucleinopathies. Clinically, synucleinopathies are heterogeneous, reflecting the somewhat selective neuronal vulnerability characteristic of each disease. The precise molecular underpinnings of synucleinopathies remain unclear, but the process of aggregation of alpha-synuclein appears as a central event. However, there is still no consensus with respect to the toxic forms of alpha-synuclein, hampering our ability to use the protein as a target for therapeutic intervention. To decipher the molecular bases of synucleinopathies, it is essential to understand the complex triangle formed between the structure, function and toxicity of alpha-synuclein. Recently, important steps have been undertaken to elucidate the role of the protein in both physiological and pathological conditions. Here, we provide an overview of recent findings in the field of alpha-synuclein research, and put forward a new perspective over paradigms that persist in the field. Establishing whether alpha-synuclein has a causative role in all synucleinopathies will enable the identification of targets for the development of novel therapeutic strategies for this devastating group of disorders. Alpha-synuclein is the speculated cornerstone of several neurodegenerative disorders known as Synucleinopathies. Nevertheless, the mechanisms underlying the pathogenic effects of this protein remain unknown. Here, we review the recent findings in the three corners of alpha-synuclein biology - structure, function and toxicity - and discuss the enigmatic roads that have accompanied alpha-synuclein from the beginning. This article is part of a special issue on Parkinson disease.
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Affiliation(s)
- Anna Villar-Piqué
- Department of NeuroDegeneration and Restorative Research, Center for Nanoscale Microscopy and Molecular Physiology of the Brain, University Medical Center Göttingen, Göttingen, Germany
| | - Tomás Lopes da Fonseca
- Department of NeuroDegeneration and Restorative Research, Center for Nanoscale Microscopy and Molecular Physiology of the Brain, University Medical Center Göttingen, Göttingen, Germany.,Instituto de Fisiologia, Faculty of Medicine, University of Lisbon, Lisboa, Portugal
| | - Tiago Fleming Outeiro
- Department of NeuroDegeneration and Restorative Research, Center for Nanoscale Microscopy and Molecular Physiology of the Brain, University Medical Center Göttingen, Göttingen, Germany. .,Instituto de Fisiologia, Faculty of Medicine, University of Lisbon, Lisboa, Portugal. .,CEDOC, Faculdade de Ciências Médicas, Universidade Nova de Lisboa, Lisboa, Portugal.
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Mechanisms of alpha-synuclein action on neurotransmission: cell-autonomous and non-cell autonomous role. Biomolecules 2015; 5:865-92. [PMID: 25985082 PMCID: PMC4496700 DOI: 10.3390/biom5020865] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2015] [Revised: 04/24/2015] [Accepted: 04/29/2015] [Indexed: 11/23/2022] Open
Abstract
Mutations and duplication/triplication of the alpha-synuclein (αSyn)-coding gene have been found to cause familial Parkinson’s disease (PD), while genetic polymorphisms in the region controlling the expression level and stability of αSyn have been identified as risk factors for idiopathic PD, pointing to the importance of wild-type (wt) αSyn dosage in the disease. Evidence that αSyn is present in the cerebrospinal fluid and interstitial brain tissue and that healthy neuronal grafts transplanted into PD patients often degenerate suggests that extracellularly-released αSyn plays a role in triggering the neurodegenerative process. αSyn’s role in neurotransmission has been shown in various cell culture models in which the protein was upregulated or deleted and in knock out and transgenic animal, with different results on αSyn’s effect on synaptic vesicle pool size and mobilization, αSyn being proposed as a negative or positive regulator of neurotransmitter release. In this review, we discuss the effect of αSyn on pre- and post-synaptic compartments in terms of synaptic vesicle trafficking, calcium entry and channel activity, and we focus on the process of exocytosis and internalization of αSyn and on the spreading of αSyn-driven effects due to the presence of the protein in the extracellular milieu.
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Yue HY, Xu J. Cholesterol regulates multiple forms of vesicle endocytosis at a mammalian central synapse. J Neurochem 2015; 134:247-60. [PMID: 25893258 DOI: 10.1111/jnc.13129] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2014] [Revised: 03/01/2015] [Accepted: 03/31/2015] [Indexed: 01/10/2023]
Abstract
Endocytosis in synapses sustains neurotransmission by recycling vesicle membrane and maintaining the homeostasis of synaptic membrane. A role of membrane cholesterol in synaptic endocytosis remains controversial because of conflicting observations, technical limitations in previous studies, and potential interference from non-specific effects after cholesterol manipulation. Furthermore, it remains unclear whether cholesterol participates in distinct forms of endocytosis that function under different activity levels. In this study, applying the whole-cell membrane capacitance measurement to monitor endocytosis in real time at the rat calyx of Held terminals, we found that disrupting cholesterol with dialysis of cholesterol oxidase or methyl-β-cyclodextrin impaired three different forms of endocytosis, including slow endocytosis, rapid endocytosis, and endocytosis of the retrievable membrane that exists at the surface before stimulation. The effects were observed when disruption of cholesterol was mild enough not to change Ca(2+) channel current or vesicle exocytosis, indicative of stringent cholesterol requirement in synaptic endocytosis. Extracting cholesterol with high concentrations of methyl-β-cyclodextrin reduced exocytosis, mainly by decreasing the readily releasable pool and the vesicle replenishment after readily releasable pool depletion. Our study suggests that cholesterol is an important, universal regulator in multiple forms of vesicle endocytosis at mammalian central synapses.
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Affiliation(s)
- Hai-Yuan Yue
- Department of Neuroscience and Regenerative Medicine, Georgia Regents University, Augusta, Georgia, USA
| | - Jianhua Xu
- Department of Neuroscience and Regenerative Medicine, Georgia Regents University, Augusta, Georgia, USA.,Department of Neurology, Medical College of Georgia, Georgia Regents University, Augusta, Georgia, USA
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Giráldez-Pérez RM, Antolín-Vallespín M, Muñoz MD, Sánchez-Capelo A. Models of α-synuclein aggregation in Parkinson's disease. Acta Neuropathol Commun 2014; 2:176. [PMID: 25497491 PMCID: PMC4272812 DOI: 10.1186/s40478-014-0176-9] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2014] [Accepted: 12/04/2014] [Indexed: 12/13/2022] Open
Abstract
Parkinson's disease (PD) is not only characterized by motor disturbances but also, by cognitive, sensory, psychiatric and autonomic dysfunction. It has been proposed that some of these symptoms might be related to the widespread pathology of α-synuclein (α-syn) aggregation in different nuclei of the central and peripheral nervous system. However, the pathogenic formation of α-syn aggregates in different brain areas of PD patients is poorly understood. Most experimental models of PD are valuable to assess specific aspects of its pathogenesis, such as toxin-induced dopaminergic neurodegeneration. However, new models are required that reflect the widespread and progressive formation of α-syn aggregates in different brain areas. Such α-syn aggregation is induced in only a few animal models, for example perikaryon inclusions are found in rats administered rotenone, aggregates with a neuritic morphology develop in mice overexpressing either mutated or wild-type α-syn, and in Smad3 deficient mice, aggregates form extensively in the perikaryon and neurites of specific brain nuclei. In this review we focus on α-syn aggregation in the human disorder, its genetics and the availability of experimental models. Indeed, evidences show that dopamine (DA) metabolism may be related to α-syn and its conformational plasticity, suggesting an interesting link between the two pathological hallmarks of PD: dopaminergic neurodegeneration and Lewy body (LB) formation.
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Affiliation(s)
- Rosa María Giráldez-Pérez
- />CIBERNED - Ser. Neurobiología – Investigación, Hospital Universitario Ramón y Cajal – IRYCIS, Ctra. Colmenar Viejo Km 9, 28034 Madrid, Spain
- />Departamento Fisiología, Facultad de Farmacia, Universidad de Sevilla, Sevilla, Spain
| | - Mónica Antolín-Vallespín
- />CIBERNED - Ser. Neurobiología – Investigación, Hospital Universitario Ramón y Cajal – IRYCIS, Ctra. Colmenar Viejo Km 9, 28034 Madrid, Spain
| | - María Dolores Muñoz
- />Unidad de Neurología Experimental, Hospital Universitario Ramón y Cajal – IRYCIS, Ctra. Colmenar Viejo Km 9, 28034 Madrid, Spain
| | - Amelia Sánchez-Capelo
- />CIBERNED - Ser. Neurobiología – Investigación, Hospital Universitario Ramón y Cajal – IRYCIS, Ctra. Colmenar Viejo Km 9, 28034 Madrid, Spain
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