1
|
Sagredo GT, Tanglay O, Shahdadpuri S, Fu Y, Halliday GM. ⍺-Synuclein levels in Parkinson's disease - Cell types and forms that contribute to pathogenesis. Exp Neurol 2024; 379:114887. [PMID: 39009177 DOI: 10.1016/j.expneurol.2024.114887] [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: 04/02/2024] [Revised: 06/28/2024] [Accepted: 07/11/2024] [Indexed: 07/17/2024]
Abstract
Parkinson's disease (PD) has two main pathological hallmarks, the loss of nigral dopamine neurons and the proteinaceous aggregations of ⍺-synuclein (⍺Syn) in neuronal Lewy pathology. These two co-existing features suggest a causative association between ⍺Syn aggregation and the underpinning mechanism of neuronal degeneration in PD. Both increased levels and post-translational modifications of ⍺Syn can contribute to the formation of pathological aggregations of ⍺Syn in neurons. Recent studies have shown that the protein is also expressed by multiple types of non-neuronal cells in the brain and peripheral tissues, suggesting additional roles of the protein and potential diversity in non-neuronal pathogenic triggers. It is important to determine (1) the threshold levels triggering ⍺Syn to convert from a biological to a pathologic form in different brain cells in PD; (2) the dominant form of pathologic ⍺Syn and the associated post-translational modification of the protein in each cell type involved in PD; and (3) the cell type associated biological processes impacted by pathologic ⍺Syn in PD. This review integrates these aspects and speculates on potential pathological mechanisms and their impact on neuronal and non-neuronal ⍺Syn in the brains of patients with PD.
Collapse
Affiliation(s)
- Giselle Tatiana Sagredo
- The University of Sydney, Brain and Mind Centre & Faculty of Medicine and Health School of Medical Sciences, Sydney, NSW, Australia; Aligning Science Across Parkinson's (ASAP) Collaborative Research Network, Chevy Chase, MD 20815, United States of America
| | - Onur Tanglay
- The University of Sydney, Brain and Mind Centre & Faculty of Medicine and Health School of Medical Sciences, Sydney, NSW, Australia
| | - Shrey Shahdadpuri
- The University of Sydney, Brain and Mind Centre & Faculty of Medicine and Health School of Medical Sciences, Sydney, NSW, Australia
| | - YuHong Fu
- The University of Sydney, Brain and Mind Centre & Faculty of Medicine and Health School of Medical Sciences, Sydney, NSW, Australia; Aligning Science Across Parkinson's (ASAP) Collaborative Research Network, Chevy Chase, MD 20815, United States of America
| | - Glenda M Halliday
- The University of Sydney, Brain and Mind Centre & Faculty of Medicine and Health School of Medical Sciences, Sydney, NSW, Australia; Aligning Science Across Parkinson's (ASAP) Collaborative Research Network, Chevy Chase, MD 20815, United States of America.
| |
Collapse
|
2
|
Ramalingam N, Haass C, Dettmer U. Physiological roles of α-synuclein serine-129 phosphorylation - not an oxymoron. Trends Neurosci 2024; 47:480-490. [PMID: 38862330 DOI: 10.1016/j.tins.2024.05.005] [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: 02/15/2024] [Revised: 04/16/2024] [Accepted: 05/06/2024] [Indexed: 06/13/2024]
Abstract
α-Synuclein (αS) is an abundant presynaptic protein that regulates neurotransmission. It is also a key protein implicated in a broad class of neurodegenerative disorders termed synucleinopathies, including Parkinson's disease (PD) and Lewy body dementia (LBD). Pathological αS deposits in these diseases, Lewy bodies (LBs)/neurites (LNs), contain about 90% of αS in its phospho-serine129 (pS129) form. Therefore, pS129 is widely used as a surrogate marker of pathology. However, recent findings demonstrate that pS129 is also physiologically triggered by neuronal activity to positively regulate synaptic transmission. In this opinion article, we contrast the literature on pathological and physiological pS129, with a special focus on the latter. We emphasize that pS129 is ambiguous and knowledge about the context is necessary to correctly interpret changes in pS129.
Collapse
Affiliation(s)
- Nagendran Ramalingam
- Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital and Harvard Medical School, Boston, MA 02115, USA.
| | - Christian Haass
- German Center for Neurodegenerative Diseases (DZNE) Munich, 81377 Munich, Germany; Chair of Metabolic Biochemistry, Biomedical Center (BMC), Faculty of Medicine, Ludwig-Maximilians-University, Munich, Germany; Munich Cluster for Systems Neurology (SyNergy), 81377 Munich, Germany
| | - Ulf Dettmer
- Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital and Harvard Medical School, Boston, MA 02115, USA.
| |
Collapse
|
3
|
Sorrentino Z, Riklan J, Lloyd G, Lucke-Wold B, Mampre D, Quintin S, Zakare-Fagbamila R, Still M, Chandra V, Foote K, Giasson B, Hilliard J. Analysis of alpha-synuclein harvested from intracranial instruments used in deep brain stimulation surgery for Parkinson's disease. RESEARCH SQUARE 2024:rs.3.rs-4369598. [PMID: 38826474 PMCID: PMC11142310 DOI: 10.21203/rs.3.rs-4369598/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2024]
Abstract
Alpha-synuclein (αSyn) forms pathologic aggregates in Parkinson's disease (PD) and is implicated in mechanisms underlying neurodegeneration. While pathologic αSyn has been extensively studied, there is currently no method to evaluate αSyn within the brains of living patients. Patients with PD are often treated with deep brain stimulation (DBS) surgery in which surgical instruments are in direct contact with neuronal tissue; herein, we describe a method by which tissue is purified from DBS surgical instruments in PD and essential tremor (ET) patients and demonstrate that αSyn is robustly detected. 24 patients undergoing DBS surgery for PD (17 patients) or ET (7 patients) were enrolled; from patient samples, 81.2 ± 44.8 μg protein (n=15) is able to be purified, with immunoblot assays specific for αSyn reactive in all tested samples. Light microscopy revealed axons and capillaries as the primary components of purified tissue (n=3). Further analysis was conducted using western blot, demonstrating that truncated αSyn (1-125 αSyn) was significantly increased in PD (n=5) compared to ET (n=3), in which αSyn misfolding is not expected (0.64 ± 0.25 vs. 0.25 ± 0.12, P = 0.046), thus showing that pathologic αSyn can be reliably purified from living PD patients with this method.
Collapse
|
4
|
Lista S, Mapstone M, Caraci F, Emanuele E, López-Ortiz S, Martín-Hernández J, Triaca V, Imbimbo C, Gabelle A, Mielke MM, Nisticò R, Santos-Lozano A, Imbimbo BP. A critical appraisal of blood-based biomarkers for Alzheimer's disease. Ageing Res Rev 2024; 96:102290. [PMID: 38580173 DOI: 10.1016/j.arr.2024.102290] [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: 11/13/2023] [Revised: 03/18/2024] [Accepted: 03/31/2024] [Indexed: 04/07/2024]
Abstract
Biomarkers that predict the clinical onset of Alzheimer's disease (AD) enable the identification of individuals in the early, preclinical stages of the disease. Detecting AD at this point may allow for more effective therapeutic interventions and optimized enrollment for clinical trials of novel drugs. The current biological diagnosis of AD is based on the AT(N) classification system with the measurement of brain deposition of amyloid-β (Aβ) ("A"), tau pathology ("T"), and neurodegeneration ("N"). Diagnostic cut-offs for Aβ1-42, the Aβ1-42/Aβ1-40 ratio, tau and hyperphosphorylated-tau concentrations in cerebrospinal fluid have been defined and may support AD clinical diagnosis. Blood-based biomarkers of the AT(N) categories have been described in the AD continuum. Cross-sectional and longitudinal studies have shown that the combination of blood biomarkers tracking neuroaxonal injury (neurofilament light chain) and neuroinflammatory pathways (glial fibrillary acidic protein) enhance sensitivity and specificity of AD clinical diagnosis and improve the prediction of AD onset. However, no international accepted cut-offs have been identified for these blood biomarkers. A kit for blood Aβ1-42/Aβ1-40 is commercially available in the U.S.; however, it does not provide a diagnosis, but simply estimates the risk of developing AD. Although blood-based AD biomarkers have a great potential in the diagnostic work-up of AD, they are not ready for the routine clinical use.
Collapse
Affiliation(s)
- Simone Lista
- i+HeALTH Strategic Research Group, Department of Health Sciences, Miguel de Cervantes European University (UEMC), Valladolid 47012, Spain.
| | - Mark Mapstone
- Department of Neurology, Institute for Memory Impairments and Neurological Disorders, University of California, Irvine, Irvine, CA 92697, USA.
| | - Filippo Caraci
- Department of Drug and Health Sciences, University of Catania, Catania 95125, Italy; Neuropharmacology and Translational Neurosciences Research Unit, Oasi Research Institute-IRCCS, Troina 94018, Italy.
| | | | - Susana López-Ortiz
- i+HeALTH Strategic Research Group, Department of Health Sciences, Miguel de Cervantes European University (UEMC), Valladolid 47012, Spain.
| | - Juan Martín-Hernández
- i+HeALTH Strategic Research Group, Department of Health Sciences, Miguel de Cervantes European University (UEMC), Valladolid 47012, Spain.
| | - Viviana Triaca
- Institute of Biochemistry and Cell Biology (IBBC), National Research Council (CNR), Rome 00015, Italy.
| | - Camillo Imbimbo
- Department of Brain and Behavioral Sciences, University of Pavia, Pavia 27100, Italy.
| | - Audrey Gabelle
- Memory Resources and Research Center, Montpellier University of Excellence i-site, Montpellier 34295, France.
| | - Michelle M Mielke
- Department of Epidemiology and Prevention, Division of Public Health Sciences, Wake Forest University School of Medicine, Winston-Salem, NC 27101, USA.
| | - Robert Nisticò
- School of Pharmacy, University of Rome "Tor Vergata", Rome 00133, Italy; Laboratory of Pharmacology of Synaptic Plasticity, EBRI Rita Levi-Montalcini Foundation, Rome 00143, Italy.
| | - Alejandro Santos-Lozano
- i+HeALTH Strategic Research Group, Department of Health Sciences, Miguel de Cervantes European University (UEMC), Valladolid 47012, Spain; Physical Activity and Health Research Group (PaHerg), Research Institute of the Hospital 12 de Octubre ('imas12'), Madrid 28041, Spain.
| | - Bruno P Imbimbo
- Department of Research and Development, Chiesi Farmaceutici, Parma 43122, Italy.
| |
Collapse
|
5
|
Chopra A, Outeiro TF. Aggregation and beyond: alpha-synuclein-based biomarkers in synucleinopathies. Brain 2024; 147:81-90. [PMID: 37526295 DOI: 10.1093/brain/awad260] [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: 04/13/2023] [Revised: 07/12/2023] [Accepted: 07/15/2023] [Indexed: 08/02/2023] Open
Abstract
Parkinson's disease is clinically known for the loss of dopaminergic neurons in the substantia nigra pars compacta and accumulation of intraneuronal cytoplasmic inclusions rich in alpha-synuclein called 'Lewy bodies' and 'Lewy neurites'. Together with dementia with Lewy bodies and multiple system atrophy, Parkinson's disease is part of a group of disorders called synucleinopathies. Currently, diagnosis of synucleinopathies is based on the clinical assessment which often takes place in advanced disease stages. While the causal role of alpha-synuclein aggregates in these disorders is still debatable, measuring the levels, types or seeding properties of different alpha-synuclein species hold great promise as biomarkers. Recent studies indicate significant differences in peptide, protein and RNA levels in blood samples from patients with Parkinson's disease. Seed amplification assays using CSF, blood, skin biopsy, olfactory swab samples show great promise for detecting synucleinopathies and even for discriminating between different synucleinopathies. Interestingly, small extracellular vesicles, such as exosomes, display differences in their cargoes in Parkinson's disease patients versus controls. In this update, we focus on alpha-synuclein aggregation and possible sources of disease-related species released in extracellular vesicles, which promise to revolutionize the diagnosis and the monitoring of disease progression.
Collapse
Affiliation(s)
- Avika Chopra
- Department of Experimental Neurodegeneration, Center for Biostructural Imaging of Neurodegeneration, University Medical Center Göttingen, 37073 Göttingen, Germany
| | - Tiago Fleming Outeiro
- Department of Experimental Neurodegeneration, Center for Biostructural Imaging of Neurodegeneration, University Medical Center Göttingen, 37073 Göttingen, Germany
- Max Planck Institute for Multidisciplinary Sciences, 37075 Göttingen, Germany
- Translational and Clinical Research Institute, Faculty of Medical Sciences, Newcastle University, Newcastle Upon Tyne NE2 4HH, UK
- Scientific Employee with an Honorary Contract at Deutsches Zentrum für Neurodegenerative Erkrankungen (DZNE), 37075 Göttingen, Germany
| |
Collapse
|
6
|
Vijiaratnam N, Foltynie T. How should we be using biomarkers in trials of disease modification in Parkinson's disease? Brain 2023; 146:4845-4869. [PMID: 37536279 PMCID: PMC10690028 DOI: 10.1093/brain/awad265] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2023] [Revised: 07/18/2023] [Accepted: 07/22/2023] [Indexed: 08/05/2023] Open
Abstract
The recent validation of the α-synuclein seed amplification assay as a biomarker with high sensitivity and specificity for the diagnosis of Parkinson's disease has formed the backbone for a proposed staging system for incorporation in Parkinson's disease clinical studies and trials. The routine use of this biomarker should greatly aid in the accuracy of diagnosis during recruitment of Parkinson's disease patients into trials (as distinct from patients with non-Parkinson's disease parkinsonism or non-Parkinson's disease tremors). There remain, however, further challenges in the pursuit of biomarkers for clinical trials of disease modifying agents in Parkinson's disease, namely: optimizing the distinction between different α-synucleinopathies; the selection of subgroups most likely to benefit from a candidate disease modifying agent; a sensitive means of confirming target engagement; and the early prediction of longer-term clinical benefit. For example, levels of CSF proteins such as the lysosomal enzyme β-glucocerebrosidase may assist in prognostication or allow enrichment of appropriate patients into disease modifying trials of agents with this enzyme as the target; the presence of coexisting Alzheimer's disease-like pathology (detectable through CSF levels of amyloid-β42 and tau) can predict subsequent cognitive decline; imaging techniques such as free-water or neuromelanin MRI may objectively track decline in Parkinson's disease even in its later stages. The exploitation of additional biomarkers to the α-synuclein seed amplification assay will, therefore, greatly add to our ability to plan trials and assess the disease modifying properties of interventions. The choice of which biomarker(s) to use in the context of disease modifying clinical trials will depend on the intervention, the stage (at risk, premotor, motor, complex) of the population recruited and the aims of the trial. The progress already made lends hope that panels of fluid biomarkers in tandem with structural or functional imaging may provide sensitive and objective methods of confirming that an intervention is modifying a key pathophysiological process of Parkinson's disease. However, correlation with clinical progression does not necessarily equate to causation, and the ongoing validation of quantitative biomarkers will depend on insightful clinical-genetic-pathophysiological comparisons incorporating longitudinal biomarker changes from those at genetic risk with evidence of onset of the pathophysiology and those at each stage of manifest clinical Parkinson's disease.
Collapse
Affiliation(s)
- Nirosen Vijiaratnam
- Department of Clinical and Movement Neurosciences, UCL Queen Square Institute of Neurology, London WC1N 3BG, UK
| | - Thomas Foltynie
- Department of Clinical and Movement Neurosciences, UCL Queen Square Institute of Neurology, London WC1N 3BG, UK
| |
Collapse
|
7
|
Savva L, Platts JA. Exploring the impact of mutation and post-translational modification on α-Synuclein: Insights from molecular dynamics simulations with and without copper. J Inorg Biochem 2023; 249:112395. [PMID: 37820444 DOI: 10.1016/j.jinorgbio.2023.112395] [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: 08/16/2023] [Revised: 09/19/2023] [Accepted: 10/04/2023] [Indexed: 10/13/2023]
Abstract
We report molecular dynamics simulations of two modifications to α-Synuclein, namely A53T mutation and phosphorylation at Ser129, which have been observed in Parkinson's disease patients. Both modifications are close to known metal binding sites, so as well as each modified peptide we also study Cu(II) bound to N-terminal and C-terminal residues. We show that A53T is predicted to cause increased β-sheet content of the peptide, with a persistent β-hairpin between residues 35-55 particularly notable. Phosphorylation has less effect on secondary structure but is predicted to significantly increase the size of the peptide, especially when bound to Cu(II), which is ascribed to reduced interaction of C-terminal sequence with central non-amyloid component. In addition, estimate of binding free energy to Cu(II) indicates A53T has little effect on metal-ion affinity, whereas phosphorylation markedly enhances the strength of binding. We suggest that the predicted changes in spatial extent and secondary structure of α-Synuclein may have implications for aggregation into Lewy bodies.
Collapse
Affiliation(s)
- Loizos Savva
- School of Chemistry, Cardiff University, Park Place, Cardiff CF10 3AT, UK
| | - James A Platts
- School of Chemistry, Cardiff University, Park Place, Cardiff CF10 3AT, UK.
| |
Collapse
|
8
|
Coughlin DG, Irwin DJ. Fluid and Biopsy Based Biomarkers in Parkinson's Disease. Neurotherapeutics 2023; 20:932-954. [PMID: 37138160 PMCID: PMC10457253 DOI: 10.1007/s13311-023-01379-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/11/2023] [Indexed: 05/05/2023] Open
Abstract
Several advances in fluid and tissue-based biomarkers for use in Parkinson's disease (PD) and other synucleinopathies have been made in the last several years. While work continues on species of alpha-synuclein (aSyn) and other proteins which can be measured from spinal fluid and plasma samples, immunohistochemistry and immunofluorescence from peripheral tissue biopsies and alpha-synuclein seeding amplification assays (aSyn-SAA: including real-time quaking induced conversion (RT-QuIC) and protein misfolding cyclic amplification (PMCA)) now offer a crucial advancement in their ability to identify aSyn species in PD patients in a categorical fashion (i.e., of aSyn + vs aSyn -); to augment clinical diagnosis however, aSyn-specific assays that have quantitative relevance to pathological burden remain an unmet need. Alzheimer's disease (AD) co-pathology is commonly found postmortem in PD, especially in those who develop dementia, and dementia with Lewy bodies (DLB). Biofluid biomarkers for tau and amyloid beta species can detect AD co-pathology in PD and DLB, which does have relevance for prognosis, but further work is needed to understand the interplay of aSyn tau, amyloid beta, and other pathological changes to generate comprehensive biomarker profiles for patients in a manner translatable to clinical trial design and individualized therapies.
Collapse
Affiliation(s)
- David G Coughlin
- Department of Neurosciences, University of California San Diego, 9444 Medical Center Drive, ECOB 03-021, MCC 0886, La Jolla, CA, 92037, USA.
| | - David J Irwin
- Department of Neurology, University of Pennsylvania, Philadelphia, PA, 19104, USA
| |
Collapse
|
9
|
Brembati V, Faustini G, Longhena F, Bellucci A. Alpha synuclein post translational modifications: potential targets for Parkinson's disease therapy? Front Mol Neurosci 2023; 16:1197853. [PMID: 37305556 PMCID: PMC10248004 DOI: 10.3389/fnmol.2023.1197853] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Accepted: 04/27/2023] [Indexed: 06/13/2023] Open
Abstract
Parkinson's disease (PD) is the most common neurodegenerative disorder with motor symptoms. The neuropathological alterations characterizing the brain of patients with PD include the loss of dopaminergic neurons of the nigrostriatal system and the presence of Lewy bodies (LB), intraneuronal inclusions that are mainly composed of alpha-synuclein (α-Syn) fibrils. The accumulation of α-Syn in insoluble aggregates is a main neuropathological feature in PD and in other neurodegenerative diseases, including LB dementia (LBD) and multiple system atrophy (MSA), which are therefore defined as synucleinopathies. Compelling evidence supports that α-Syn post translational modifications (PTMs) such as phosphorylation, nitration, acetylation, O-GlcNAcylation, glycation, SUMOylation, ubiquitination and C-terminal cleavage, play important roles in the modulation α-Syn aggregation, solubility, turnover and membrane binding. In particular, PTMs can impact on α-Syn conformational state, thus supporting that their modulation can in turn affect α-Syn aggregation and its ability to seed further soluble α-Syn fibrillation. This review focuses on the importance of α-Syn PTMs in PD pathophysiology but also aims at highlighting their general relevance as possible biomarkers and, more importantly, as innovative therapeutic targets for synucleinopathies. In addition, we call attention to the multiple challenges that we still need to face to enable the development of novel therapeutic approaches modulating α-Syn PTMs.
Collapse
Affiliation(s)
| | | | | | - Arianna Bellucci
- Division of Pharmacology, Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy
| |
Collapse
|
10
|
Dutta S, Hornung S, Taha HB, Biggs K, Siddique I, Chamoun LM, Shahpasand-Kroner H, Lantz C, Herrera-Vaquero M, Stefanova N, Loo JA, Bitan G. Development of a Novel Electrochemiluminescence ELISA for Quantification of α-Synuclein Phosphorylated at Ser 129 in Biological Samples. ACS Chem Neurosci 2023; 14:1238-1248. [PMID: 36920792 PMCID: PMC10080651 DOI: 10.1021/acschemneuro.2c00676] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/16/2023] Open
Abstract
Synucleinopathies are a group of neurodegenerative diseases including Parkinson's disease (PD), dementia with Lewy bodies (DLB), and multiple system atrophy (MSA). These diseases are characterized by the aggregation and deposition of α-synuclein (α-syn) in Lewy bodies (LBs) in PD and DLB or as glial cytoplasmic inclusions in MSA. In healthy brains, only ∼4% of α-syn is phosphorylated at Ser129 (pS129-α-syn), whereas >90% pS129-α-syn may be found in LBs, suggesting that pS129-α-syn could be a useful biomarker for synucleinopathies. However, a widely available, robust, sensitive, and reproducible method for measuring pS129-α-syn in biological fluids is currently missing. We used Meso Scale Discovery (MSD)'s electrochemiluminescence platform to create a new assay for sensitive detection of pS129-α-syn. We evaluated several combinations of capture and detection antibodies and used semisynthetic pS129-α-syn as a standard for the assay at a concentration range from 0.5 to 6.6 × 104 pg/mL. Using the antibody EP1536Y for capture and an anti-human α-syn antibody (MSD) for detection was the best combination in terms of assay sensitivity, specificity, and reproducibility. We tested the utility of the assay for the detection and quantification of pS129-α-syn in human cerebrospinal fluid, serum, plasma, saliva, and CNS-originating small extracellular vesicles, as well as in mouse brain lysates. Our data suggest that the assay can become a widely used method for detecting pS129-α-syn in biomedical studies including when only a limited volume of sample is available and high sensitivity is required, offering new opportunities for diagnostic biomarkers, monitoring disease progression, and quantifying outcome measures in clinical trials.
Collapse
Affiliation(s)
| | | | | | | | | | | | | | | | - Marcos Herrera-Vaquero
- Division of Neurobiology, Department of Neurology, Medical University of Innsbruck, 6020 Innsbruck, Austria
| | - Nadia Stefanova
- Division of Neurobiology, Department of Neurology, Medical University of Innsbruck, 6020 Innsbruck, Austria
| | | | | |
Collapse
|
11
|
Canever JB, Soares ES, de Avelar NCP, Cimarosti HI. Targeting α-synuclein post-translational modifications in Parkinson's disease. Behav Brain Res 2023; 439:114204. [PMID: 36372243 DOI: 10.1016/j.bbr.2022.114204] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Revised: 10/25/2022] [Accepted: 11/04/2022] [Indexed: 11/13/2022]
Abstract
Parkinson's disease (PD) is a neurodegenerative disease characterized by the progressive loss of dopaminergic neurons in the nigrostriatal pathway. Although the exact mechanisms underlying PD are still not completely understood, it is well accepted that α-synuclein plays key pathophysiological roles as the main constituent of the cytoplasmic inclusions known as Lewy bodies. Several post-translational modifications (PTMs), such as the best-known phosphorylation, target α-synuclein and are thus implicated in its physiological and pathological functions. In this review, we present (1) an overview of the pathophysiological roles of α-synuclein, (2) a descriptive analysis of α-synuclein PTMs, including phosphorylation, ubiquitination, SUMOylation, acetylation, glycation, truncation, and O-GlcNAcylation, as well as (3) a brief summary on α-synuclein PTMs as potential biomarkers for PD. A better understanding of α-synuclein PTMs is of paramount importance for elucidating the mechanisms underlying PD and can thus be expected to improve early detection and monitoring disease progression, as well as identify promising new therapeutic targets.
Collapse
Affiliation(s)
- Jaquelini B Canever
- Post-Graduate Program in Neuroscience, Federal University of Santa Catarina (UFSC), Florianópolis, Santa Catarina, Brazil; Laboratory of Aging, Resources and Rheumatology, UFSC, Araranguá, Santa Catarina, Brazil
| | - Ericks Sousa Soares
- Post-Graduate Program in Pharmacology, UFSC, Florianópolis, Santa Catarina, Brazil
| | - Núbia C P de Avelar
- Laboratory of Aging, Resources and Rheumatology, UFSC, Araranguá, Santa Catarina, Brazil
| | - Helena I Cimarosti
- Post-Graduate Program in Neuroscience, Federal University of Santa Catarina (UFSC), Florianópolis, Santa Catarina, Brazil; Post-Graduate Program in Pharmacology, UFSC, Florianópolis, Santa Catarina, Brazil.
| |
Collapse
|
12
|
Review of Technological Challenges in Personalised Medicine and Early Diagnosis of Neurodegenerative Disorders. Int J Mol Sci 2023; 24:ijms24043321. [PMID: 36834733 PMCID: PMC9968142 DOI: 10.3390/ijms24043321] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2022] [Revised: 01/31/2023] [Accepted: 02/02/2023] [Indexed: 02/11/2023] Open
Abstract
Neurodegenerative disorders are characterised by progressive neuron loss in specific brain areas. The most common are Alzheimer's disease and Parkinson's disease; in both cases, diagnosis is based on clinical tests with limited capability to discriminate between similar neurodegenerative disorders and detect the early stages of the disease. It is common that by the time a patient is diagnosed with the disease, the level of neurodegeneration is already severe. Thus, it is critical to find new diagnostic methods that allow earlier and more accurate disease detection. This study reviews the methods available for the clinical diagnosis of neurodegenerative diseases and potentially interesting new technologies. Neuroimaging techniques are the most widely used in clinical practice, and new techniques such as magnetic resonance imaging (MRI) and positron emission tomography (PET) have significantly improved the diagnosis quality. Identifying biomarkers in peripheral samples such as blood or cerebrospinal fluid is a major focus of the current research on neurodegenerative diseases. The discovery of good markers could allow preventive screening to identify early or asymptomatic stages of the neurodegenerative process. These methods, in combination with artificial intelligence, could contribute to the generation of predictive models that will help clinicians in the early diagnosis, stratification, and prognostic assessment of patients, leading to improvements in patient treatment and quality of life.
Collapse
|
13
|
Arlinghaus R, Iba M, Masliah E, Cookson MR, Landeck N. Specific Detection of Physiological S129 Phosphorylated α-Synuclein in Tissue Using Proximity Ligation Assay. JOURNAL OF PARKINSON'S DISEASE 2023; 13:255-270. [PMID: 36847016 PMCID: PMC10041430 DOI: 10.3233/jpd-213085] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 01/31/2023] [Indexed: 03/01/2023]
Abstract
BACKGROUND Synucleinopathies are a group of neurodegenerative disorders that are pathologically characterized by intracellular aggregates called Lewy bodies. Lewy bodies are primarily composed of α-synuclein (asyn) protein, which is mostly phosphorylated at serine 129 (pS129) when aggregated and therefore used as a marker for pathology. Currently commercial antibodies against pS129 asyn stain aggregates well but in healthy brains cross react with other proteins, thus making it difficult to specifically detect physiological pS129 asyn. OBJECTIVE To develop a staining procedure that detects endogenous and physiological relevant pS129 asyn with high specificity and low background. METHODS We used the fluorescent and brightfield in situ proximity ligation assay (PLA) to specifically detect pS129 asyn in cell culture, mouse, and human brain sections. RESULTS The pS129 asyn PLA specifically stained physiological and soluble pS129 asyn in cell culture, mouse brain sections, and human brain tissue without significant cross-reactivity or background signal. However, this technique was not successful in detecting Lewy bodies in human brain tissue. CONCLUSION We successfully developed a novel PLA method that can, in the future, be used on in vitro and in vivo samples as a tool to explore and better understand the cellular localization and function of pS129 asyn in health and disease.
Collapse
Affiliation(s)
- Ryan Arlinghaus
- Cell Biology and Gene Expression Section, Laboratory of Neurogenetics, National Institute on Aging, NIH, Bethesda, MD, USA
| | - Michiyo Iba
- Molecular Neuropathology Section, Laboratory of Neurogenetics, National Institutes on Aging, NIH, Bethesda, MD, USA
| | - Eliezer Masliah
- Molecular Neuropathology Section, Laboratory of Neurogenetics, National Institutes on Aging, NIH, Bethesda, MD, USA
- Division of Neuroscience, National Institute on Aging, NIH, Bethesda, MD, USA
| | - Mark R. Cookson
- Cell Biology and Gene Expression Section, Laboratory of Neurogenetics, National Institute on Aging, NIH, Bethesda, MD, USA
| | - Natalie Landeck
- Cell Biology and Gene Expression Section, Laboratory of Neurogenetics, National Institute on Aging, NIH, Bethesda, MD, USA
| |
Collapse
|
14
|
Lashuel HA, Mahul-Mellier AL, Novello S, Hegde RN, Jasiqi Y, Altay MF, Donzelli S, DeGuire SM, Burai R, Magalhães P, Chiki A, Ricci J, Boussouf M, Sadek A, Stoops E, Iseli C, Guex N. Revisiting the specificity and ability of phospho-S129 antibodies to capture alpha-synuclein biochemical and pathological diversity. NPJ Parkinsons Dis 2022; 8:136. [PMID: 36266318 PMCID: PMC9584898 DOI: 10.1038/s41531-022-00388-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Accepted: 08/30/2022] [Indexed: 11/08/2022] Open
Abstract
Antibodies against phosphorylated alpha-synuclein (aSyn) at S129 have emerged as the primary tools to investigate, monitor, and quantify aSyn pathology in the brain and peripheral tissues of patients with Parkinson's disease and other neurodegenerative diseases. Herein, we demonstrate that the co-occurrence of multiple pathology-associated C-terminal post-translational modifications (PTMs) (e.g., phosphorylation at Tyrosine 125 or truncation at residue 133 or 135) differentially influences the detection of pS129-aSyn species by pS129-aSyn antibodies. These observations prompted us to systematically reassess the specificity of the most commonly used pS129 antibodies against monomeric and aggregated forms of pS129-aSyn in mouse brain slices, primary neurons, mammalian cells and seeding models of aSyn pathology formation. We identified two antibodies that are insensitive to pS129 neighboring PTMs. Although most pS129 antibodies showed good performance in detecting aSyn aggregates in cells, neurons and mouse brain tissue containing abundant aSyn pathology, they also showed cross-reactivity towards other proteins and often detected non-specific low and high molecular weight bands in aSyn knock-out samples that could be easily mistaken for monomeric or high molecular weight aSyn species. Our observations suggest that not all pS129 antibodies capture the biochemical and morphological diversity of aSyn pathology, and all should be used with the appropriate protein standards and controls when investigating aSyn under physiological conditions. Finally, our work underscores the need for more pS129 antibodies that are not sensitive to neighboring PTMs and more thorough characterization and validation of existing and new antibodies.
Collapse
Affiliation(s)
- Hilal A Lashuel
- Laboratory of Molecular and Chemical Biology of Neurodegeneration, School of Life Sciences, Brain Mind Institute, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015, Lausanne, Switzerland.
| | - Anne-Laure Mahul-Mellier
- Laboratory of Molecular and Chemical Biology of Neurodegeneration, School of Life Sciences, Brain Mind Institute, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015, Lausanne, Switzerland
| | - Salvatore Novello
- Laboratory of Molecular and Chemical Biology of Neurodegeneration, School of Life Sciences, Brain Mind Institute, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015, Lausanne, Switzerland
| | - Ramanath Narayana Hegde
- Laboratory of Molecular and Chemical Biology of Neurodegeneration, School of Life Sciences, Brain Mind Institute, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015, Lausanne, Switzerland
| | - Yllza Jasiqi
- Laboratory of Molecular and Chemical Biology of Neurodegeneration, School of Life Sciences, Brain Mind Institute, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015, Lausanne, Switzerland
| | - Melek Firat Altay
- Laboratory of Molecular and Chemical Biology of Neurodegeneration, School of Life Sciences, Brain Mind Institute, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015, Lausanne, Switzerland
| | - Sonia Donzelli
- Laboratory of Molecular and Chemical Biology of Neurodegeneration, School of Life Sciences, Brain Mind Institute, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015, Lausanne, Switzerland
| | - Sean M DeGuire
- Laboratory of Molecular and Chemical Biology of Neurodegeneration, School of Life Sciences, Brain Mind Institute, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015, Lausanne, Switzerland
| | - Ritwik Burai
- Laboratory of Molecular and Chemical Biology of Neurodegeneration, School of Life Sciences, Brain Mind Institute, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015, Lausanne, Switzerland
| | - Pedro Magalhães
- Laboratory of Molecular and Chemical Biology of Neurodegeneration, School of Life Sciences, Brain Mind Institute, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015, Lausanne, Switzerland
| | - Anass Chiki
- Laboratory of Molecular and Chemical Biology of Neurodegeneration, School of Life Sciences, Brain Mind Institute, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015, Lausanne, Switzerland
| | - Jonathan Ricci
- Laboratory of Molecular and Chemical Biology of Neurodegeneration, School of Life Sciences, Brain Mind Institute, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015, Lausanne, Switzerland
| | - Manel Boussouf
- Laboratory of Molecular and Chemical Biology of Neurodegeneration, School of Life Sciences, Brain Mind Institute, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015, Lausanne, Switzerland
| | - Ahmed Sadek
- Laboratory of Molecular and Chemical Biology of Neurodegeneration, School of Life Sciences, Brain Mind Institute, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015, Lausanne, Switzerland
| | - Erik Stoops
- ADx NeuroSciences, Technologiepark 94, Ghent, Belgium
| | - Christian Iseli
- Bioinformatics Competence Center, Ecole Polytechnique Fédérale de Lausanne, 1015, Lausanne, Switzerland
- Bioinformatics Competence Center, University of Lausanne, 1015, Lausanne, Switzerland
| | - Nicolas Guex
- Bioinformatics Competence Center, Ecole Polytechnique Fédérale de Lausanne, 1015, Lausanne, Switzerland
- Bioinformatics Competence Center, University of Lausanne, 1015, Lausanne, Switzerland
| |
Collapse
|
15
|
Opportunities and challenges of alpha-synuclein as a potential biomarker for Parkinson's disease and other synucleinopathies. NPJ Parkinsons Dis 2022; 8:93. [PMID: 35869066 PMCID: PMC9307631 DOI: 10.1038/s41531-022-00357-0] [Citation(s) in RCA: 48] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2022] [Accepted: 06/24/2022] [Indexed: 02/07/2023] Open
Abstract
Parkinson’s disease (PD), the second most common progressive neurodegenerative disease, develops and progresses for 10–15 years before the clinical diagnostic symptoms of the disease are manifested. Furthermore, several aspects of PD pathology overlap with other neurodegenerative diseases (NDDs) linked to alpha-synuclein (aSyn) aggregation, also called synucleinopathies. Therefore, there is an urgent need to discover and validate early diagnostic and prognostic markers that reflect disease pathophysiology, progression, severity, and potential differences in disease mechanisms between PD and other NDDs. The close association between aSyn and the development of pathology in synucleinopathies, along with the identification of aSyn species in biological fluids, has led to increasing interest in aSyn species as potential biomarkers for early diagnosis of PD and differentiate it from other synucleinopathies. In this review, we (1) provide an overview of the progress toward mapping the distribution of aSyn species in the brain, peripheral tissues, and biological fluids; (2) present comparative and critical analysis of previous studies that measured total aSyn as well as other species such as modified and aggregated forms of aSyn in different biological fluids; and (3) highlight conceptual and technical gaps and challenges that could hinder the development and validation of reliable aSyn biomarkers; and (4) outline a series of recommendations to address these challenges. Finally, we propose a combined biomarker approach based on integrating biochemical, aggregation and structure features of aSyn, in addition to other biomarkers of neurodegeneration. We believe that capturing the diversity of aSyn species is essential to develop robust assays and diagnostics for early detection, patient stratification, monitoring of disease progression, and differentiation between synucleinopathies. This could transform clinical trial design and implementation, accelerate the development of new therapies, and improve clinical decisions and treatment strategies.
Collapse
|
16
|
Kwon EH, Tennagels S, Gold R, Gerwert K, Beyer L, Tönges L. Update on CSF Biomarkers in Parkinson's Disease. Biomolecules 2022; 12:biom12020329. [PMID: 35204829 PMCID: PMC8869235 DOI: 10.3390/biom12020329] [Citation(s) in RCA: 30] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Revised: 02/02/2022] [Accepted: 02/16/2022] [Indexed: 02/07/2023] Open
Abstract
Progress in developing disease-modifying therapies in Parkinson’s disease (PD) can only be achieved through reliable objective markers that help to identify subjects at risk. This includes an early and accurate diagnosis as well as continuous monitoring of disease progression and therapy response. Although PD diagnosis still relies mainly on clinical features, encouragingly, advances in biomarker discovery have been made. The cerebrospinal fluid (CSF) is a biofluid of particular interest to study biomarkers since it is closest to the brain structures and therefore could serve as an ideal source to reflect ongoing pathologic processes. According to the key pathophysiological mechanisms, the CSF status of α-synuclein species, markers of amyloid and tau pathology, neurofilament light chain, lysosomal enzymes and markers of neuroinflammation provide promising preliminary results as candidate biomarkers. Untargeted approaches in the field of metabolomics provide insights into novel and interconnected biological pathways. Markers based on genetic forms of PD can contribute to identifying subgroups suitable for gene-targeted treatment strategies that might also be transferable to sporadic PD. Further validation analyses in large PD cohort studies will identify the CSF biomarker or biomarker combinations with the best value for clinical and research purposes.
Collapse
Affiliation(s)
- Eun Hae Kwon
- Department of Neurology, St. Josef-Hospital, Ruhr-University Bochum, D-44791 Bochum, Germany; (E.H.K.); (S.T.); (R.G.)
| | - Sabrina Tennagels
- Department of Neurology, St. Josef-Hospital, Ruhr-University Bochum, D-44791 Bochum, Germany; (E.H.K.); (S.T.); (R.G.)
| | - Ralf Gold
- Department of Neurology, St. Josef-Hospital, Ruhr-University Bochum, D-44791 Bochum, Germany; (E.H.K.); (S.T.); (R.G.)
- Center for Protein Diagnostics (ProDi), Ruhr University Bochum, D-44801 Bochum, Germany; (K.G.); (L.B.)
| | - Klaus Gerwert
- Center for Protein Diagnostics (ProDi), Ruhr University Bochum, D-44801 Bochum, Germany; (K.G.); (L.B.)
- Faculty of Biology and Biotechnology, Department of Biophysics, Ruhr University Bochum, D-44801 Bochum, Germany
| | - Léon Beyer
- Center for Protein Diagnostics (ProDi), Ruhr University Bochum, D-44801 Bochum, Germany; (K.G.); (L.B.)
- Faculty of Biology and Biotechnology, Department of Biophysics, Ruhr University Bochum, D-44801 Bochum, Germany
| | - Lars Tönges
- Department of Neurology, St. Josef-Hospital, Ruhr-University Bochum, D-44791 Bochum, Germany; (E.H.K.); (S.T.); (R.G.)
- Center for Protein Diagnostics (ProDi), Ruhr University Bochum, D-44801 Bochum, Germany; (K.G.); (L.B.)
- Correspondence: ; Tel.: +49-234-509-2420; Fax: +49-234-509-2439
| |
Collapse
|
17
|
Chen R, Gu X, Wang X. α-Synuclein in Parkinson's disease and advances in detection. Clin Chim Acta 2022; 529:76-86. [PMID: 35176268 DOI: 10.1016/j.cca.2022.02.006] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Revised: 02/08/2022] [Accepted: 02/10/2022] [Indexed: 12/26/2022]
Abstract
Parkinson's disease (PD) is a threatening neurodegenerative disorder that seriously affects patients' life quality. Substantial evidence links the overexpression and abnormal aggregation of alpha-synuclein (α-Syn) to PD. α-Syn has been identified as a characteristic biomarker of PD, which indicates its great value of diagnosis and designing effective therapeutic strategy. This article systematically summarizes the pathogenic process of α-Syn based on recent researches, outlines and compares commonly used analysis and detection technologies of α-Syn. Specifically, the detection of α-Syn by new electrochemical, photochemical, and crystal biosensors is mainly examined. Furthermore, the speculation of future study orientation is discussed, which provides reference for the further research and application of α-Syn as biomarker.
Collapse
Affiliation(s)
- Rong Chen
- School of Medicine, Southeast University, Nanjing 210009, China
| | - Xuan Gu
- Key Laboratory of Environmental Medicine Engineering of Ministry of Education, School of Public Health, Southeast University, Nanjing 210009, China
| | - Xiaoying Wang
- Key Laboratory of Environmental Medicine Engineering of Ministry of Education, School of Public Health, Southeast University, Nanjing 210009, China.
| |
Collapse
|
18
|
Ostrakhovitch EA, Song ES, Macedo JKA, Gentry MS, Quintero JE, van Horne C, Yamasaki TR. Analysis of circulating metabolites to differentiate Parkinson's disease and essential tremor. Neurosci Lett 2021; 769:136428. [PMID: 34971771 DOI: 10.1016/j.neulet.2021.136428] [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] [Received: 08/30/2021] [Revised: 12/24/2021] [Accepted: 12/24/2021] [Indexed: 12/26/2022]
Abstract
Parkinson disease (PD) and essential tremor (ET) are two common adult-onset tremor disorders in which prevalence increases with age. PD is a neurodegenerative condition with progressive disability. In ET, neurodegeneration is not an established etiology. We sought to determine whether an underlying metabolic pattern may differentiate ET from PD. Circulating metabolites in plasma and cerebrospinal fluid were analyzed using gas chromatography-mass spectroscopy. There were several disrupted pathways in PD compared to ET plasma including glycolysis, tyrosine, phenylalanine, tyrosine biosynthesis, purine and glutathione metabolism. Elevated α-synuclein levels in plasma and CSF distinguished PD from ET. The perturbed metabolic state in PD was associated with imbalance in the pentose phosphate pathway, deficits in energy production, and change in NADPH, NADH and nicotinamide phosphoribosyltransferase levels. This work demonstrates significant metabolic differences in plasma and CSF of PD and ET patients.
Collapse
Affiliation(s)
| | - Eun-Suk Song
- Department of Neurology, University of Kentucky, Lexington, KY, 40536, USA
| | - Jessica K A Macedo
- Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, KY, 40536, USA
| | - Matthew S Gentry
- Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, KY, 40536, USA
| | - Jorge E Quintero
- Department of Neurosurgery, University of Kentucky, Lexington, KY, 40536, USA
| | - Craig van Horne
- Department of Neurosurgery, University of Kentucky, Lexington, KY, 40536, USA
| | - Tritia R Yamasaki
- Department of Neurology, University of Kentucky, Lexington, KY, 40536, USA; Department of Neuroscience, University of Kentucky, Lexington, KY, 40536, USA; Veterans Affairs Medical Center, Lexington, KY, 40536, USA
| |
Collapse
|
19
|
Kelly R, Cairns AG, Ådén J, Almqvist F, Bemelmans AP, Brouillet E, Patton T, McKernan DP, Dowd E. The Small Molecule Alpha-Synuclein Aggregator, FN075, Enhances Alpha-Synuclein Pathology in Subclinical AAV Rat Models. Biomolecules 2021; 11:1685. [PMID: 34827685 PMCID: PMC8615715 DOI: 10.3390/biom11111685] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2021] [Revised: 11/03/2021] [Accepted: 11/09/2021] [Indexed: 12/13/2022] Open
Abstract
Animal models of Parkinson's disease, in which the human α-synuclein transgene is overexpressed in the nigrostriatal pathway using viral vectors, are widely considered to be the most relevant models of the human condition. However, although highly valid, these models have major limitations related to reliability and variability, with many animals exhibiting pronounced α-synuclein expression failing to demonstrate nigrostriatal neurodegeneration or motor dysfunction. Therefore, the aim of this study was to determine if sequential intra-nigral administration of AAV-α-synuclein followed by the small α-synuclein aggregating molecule, FN075, would enhance or precipitate the associated α-synucleinopathy, nigrostriatal pathology and motor dysfunction in subclinical models. Rats were given unilateral intra-nigral injections of AAV-α-synuclein (either wild-type or A53T mutant) followed four weeks later by a unilateral intra-nigral injection of FN075, after which they underwent behavioral testing for lateralized motor functionality until they were sacrificed for immunohistological assessment at 20 weeks after AAV administration. In line with expectations, both of the AAV vectors induced widespread overexpression of human α-synuclein in the substantia nigra and striatum. Sequential administration of FN075 significantly enhanced the α-synuclein pathology with increased density and accumulation of the pathological form of the protein phosphorylated at serine 129 (pS129-α-synuclein). However, despite this enhanced α-synuclein pathology, FN075 did not precipitate nigrostriatal degeneration or motor dysfunction in these subclinical AAV models. In conclusion, FN075 holds significant promise as an approach to enhancing the α-synuclein pathology in viral overexpression models, but further studies are required to determine if alternative administration regimes for this molecule could improve the reliability and variability in these models.
Collapse
Affiliation(s)
- Rachel Kelly
- Pharmacology & Therapeutics and Galway Neuroscience Centre, National University of Ireland Galway, H91 W5P7 Galway, Ireland; (R.K.); (T.P.); (D.P.M.)
| | - Andrew G. Cairns
- Department of Chemistry, Umeå University, 901 87 Umeå, Sweden; (A.G.C.); (J.Å.); (F.A.)
| | - Jörgen Ådén
- Department of Chemistry, Umeå University, 901 87 Umeå, Sweden; (A.G.C.); (J.Å.); (F.A.)
| | - Fredrik Almqvist
- Department of Chemistry, Umeå University, 901 87 Umeå, Sweden; (A.G.C.); (J.Å.); (F.A.)
| | - Alexis-Pierre Bemelmans
- Université Paris-Saclay, CEA, CNRS, Laboratoire des Maladies Neurodégénératives, MIRCen, F-92265 Fontenay-aux-Roses, France; (A.-P.B.); (E.B.)
| | - Emmanuel Brouillet
- Université Paris-Saclay, CEA, CNRS, Laboratoire des Maladies Neurodégénératives, MIRCen, F-92265 Fontenay-aux-Roses, France; (A.-P.B.); (E.B.)
| | - Tommy Patton
- Pharmacology & Therapeutics and Galway Neuroscience Centre, National University of Ireland Galway, H91 W5P7 Galway, Ireland; (R.K.); (T.P.); (D.P.M.)
| | - Declan P. McKernan
- Pharmacology & Therapeutics and Galway Neuroscience Centre, National University of Ireland Galway, H91 W5P7 Galway, Ireland; (R.K.); (T.P.); (D.P.M.)
| | - Eilís Dowd
- Pharmacology & Therapeutics and Galway Neuroscience Centre, National University of Ireland Galway, H91 W5P7 Galway, Ireland; (R.K.); (T.P.); (D.P.M.)
| |
Collapse
|
20
|
Li XY, Li W, Li X, Li XR, Sun L, Yang W, Cai Y, Chen Z, Wu J, Wang C, Yu S. Alterations of Erythrocytic Phosphorylated Alpha-Synuclein in Different Subtypes and Stages of Parkinson's Disease. Front Aging Neurosci 2021; 13:623977. [PMID: 34658833 PMCID: PMC8511781 DOI: 10.3389/fnagi.2021.623977] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Accepted: 02/03/2021] [Indexed: 11/13/2022] Open
Abstract
Serine 129-phosphorylated alpha-synuclein (pS-α-syn) is a major form of α-syn relevant to the pathogenesis of Parkinson's disease (PD), which has been recently detected in red blood cells (RBCs). However, alterations of RBC-derived pS-α-syn (pS-α-syn-RBC) in different subtypes and stages of PD remains to be investigated. In the present study, by using enzyme-linked immunosorbent assay (ELISA) to measure pS-α-syn-RBC, we demonstrated significantly higher levels of pS-α-syn-RBC in PD patients than in healthy controls. pS-α-syn-RBC separated the patients well from the controls, with a sensitivity of 93.39% (95% CI: 90.17-95.81%), a specificity of 93.11% (95% CI: 89.85-95.58%), and an area under the curve (AUC) of 0.96. Considering motor subtypes, the levels of pS-α-syn-RBC were significantly higher in late-onset than young-onset PD (p = 0.013) and in those with postural instability and gait difficulty than with tremor-dominant (TD) phenotype (p = 0.029). In addition, the levels of pS-α-syn-RBC were also different in non-motor subtypes, which were significantly lower in patients with cognitive impairment (p = 0.012) and olfactory loss (p = 0.004) than in those without such symptoms. Moreover, the levels of pS-α-syn-RBC in PD patients were positively correlated with disease duration and Hoehn & Yahr stages (H&Y) (p for trend =0.02 and <0.001) as well as UPDRS III (R 2 = 0.031, p = 0.0042) and MoCA scores (R 2 = 0.048, p = 0.0004). The results obtained suggest that pS-α-syn-RBC can be used as a potential biomarker for not only separating PD patients from healthy controls but also predicting the subtypes and stages of PD.
Collapse
Affiliation(s)
- Xu-Ying Li
- Department of Neurobiology, Xuanwu Hospital of Capital Medical University, Beijing, China.,Department of Neurology, Xuanwu Hospital of Capital Medical University, Beijing, China
| | - Wei Li
- Department of Neurobiology, Xuanwu Hospital of Capital Medical University, Beijing, China
| | - Xin Li
- Department of Neurobiology, Xuanwu Hospital of Capital Medical University, Beijing, China
| | - Xu-Ran Li
- Department of Neurobiology, Xuanwu Hospital of Capital Medical University, Beijing, China
| | - Linjuan Sun
- Department of Neurology, Xiyuan Hospital, China Academy of Chinese Medical Sciences, Beijing, China
| | - Weiwei Yang
- Department of Neurobiology, Xuanwu Hospital of Capital Medical University, Beijing, China
| | - Yanning Cai
- Department of Neurobiology, Xuanwu Hospital of Capital Medical University, Beijing, China
| | - Zhigang Chen
- Department of Neurology, Dongfang Hospital of Beijing University of Chinese Medicine, Beijing, China
| | - Jun Wu
- Department of Neurology, Peking University Shenzhen Hospital, Guangdong, China
| | - Chaodong Wang
- Department of Neurology, Xuanwu Hospital of Capital Medical University, Beijing, China.,National Clinical Research Center for Geriatric Diseases, Beijing, China
| | - Shun Yu
- Department of Neurobiology, Xuanwu Hospital of Capital Medical University, Beijing, China
| |
Collapse
|
21
|
Schulz I, Kruse N, Gera RG, Kremer T, Cedarbaum J, Barbour R, Zago W, Schade S, Otte B, Bartl M, Hutten SJ, Trenkwalder C, Mollenhauer B. Systematic Assessment of 10 Biomarker Candidates Focusing on α-Synuclein-Related Disorders. Mov Disord 2021; 36:2874-2887. [PMID: 34363416 DOI: 10.1002/mds.28738] [Citation(s) in RCA: 55] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 06/30/2021] [Accepted: 07/14/2021] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND Objective diagnostic biomarkers are needed to support a clinical diagnosis. OBJECTIVES To analyze markers in various neurodegenerative disorders to identify diagnostic biomarker candidates for mainly α-synuclein (aSyn)-related disorders (ASRD) in serum and/or cerebrospinal fluid (CSF). METHODS Upon initial testing of commercially available kits or published protocols for the quantification of the candidate markers, assays for the following were selected: total and phosphorylated aSyn (pS129aSyn), neurofilament light chain (NfL), phosphorylated neurofilament heavy chain (pNfH), tau protein (tau), ubiquitin C-terminal hydrolase L1 (UCHL-1), glial fibrillary acidic protein (GFAP), calcium-binding protein B (S100B), soluble triggering receptor expressed on myeloid cells 2 (sTREM-2), and chitinase-3-like protein 1 (YKL-40). The cohort comprised participants with Parkinson's disease (PD, n = 151), multiple system atrophy (MSA, n = 17), dementia with Lewy bodies (DLB, n = 45), tau protein-related neurodegenerative disorders (n = 80, comprising patients with progressive supranuclear palsy (PSP, n = 38), corticobasal syndrome (CBS, n = 16), Alzheimer's disease (AD, n = 11), and frontotemporal degeneration/amyotrophic lateral sclerosis (FTD/ALS, n = 15), as well as healthy controls (HC, n = 20). Receiver operating curves (ROC) with area under the curves (AUC) are given for each marker. RESULTS CSF total aSyn was decreased. NfL, pNfH, UCHL-1, GFAP, S100B, and sTREM-2 were increased in patients with neurodegenerative disease versus HC (P < 0.05). As expected, some of the markers were highest in AD (i.e., UCHL-1, GFAP, S100B, sTREM-2, YKL-40). Within ASRD, CSF NfL levels were higher in MSA than PD and DLB (P < 0.05). Comparing PD to HC, interesting serum markers were S100B (AUC: 0.86), sTREM2 (AUC: 0.87), and NfL (AUC: 0.78). CSF S100B and serum GFAP were highest in DLB. CONCLUSIONS Levels of most marker candidates tested in serum and CSF significantly differed between disease groups and HC. In the stratification of PD versus other tau- or aSyn-related conditions, CSF NfL levels best discriminated PD and MSA. CSF S100B and serum GFAP best discriminated PD and DLB. © 2021 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson Movement Disorder Society.
Collapse
Affiliation(s)
| | - Niels Kruse
- Department of Neuropathology, University Medical Centre Goettingen, Goettingen, Germany
| | - Roland G Gera
- Department of Medical Statistics, University Medical Centre Goettingen, Goettingen, Germany
| | - Thomas Kremer
- Roche Pharmaceutical Research and Early Development, NRD Neuroscience and Rare Disease, Roche Innovation Center Basel, F. Hoffmann-La Roche Ltd, Basel, Switzerland
| | - Jesse Cedarbaum
- Coeruleus Clinical Sciences LLC, Woodbidge, Connecticut, USA.,Yale University School of Medicine, New Haven, Connecticut, USA
| | - Robin Barbour
- Prothena Biosciences Inc., San Francisco, California, USA
| | - Wagner Zago
- Prothena Biosciences Inc., San Francisco, California, USA
| | - Sebastian Schade
- Department of Neurology, University Medical Centre Goettingen, Goettingen, Germany
| | - Birgit Otte
- Department of Neurology, University Medical Centre Goettingen, Goettingen, Germany
| | - Michael Bartl
- Department of Neurology, University Medical Centre Goettingen, Goettingen, Germany
| | - Samantha J Hutten
- The Michael J. Fox Foundation for Parkinson's Research, New York, New York, USA
| | - Claudia Trenkwalder
- Paracelsus-Elena-Klinik, Kassel, Germany.,Department of Neurosurgery, University Medical Centre Goettingen, Goettingen, Germany
| | - Brit Mollenhauer
- Paracelsus-Elena-Klinik, Kassel, Germany.,Department of Neurology, University Medical Centre Goettingen, Goettingen, Germany
| |
Collapse
|
22
|
Manzanza NDO, Sedlackova L, Kalaria RN. Alpha-Synuclein Post-translational Modifications: Implications for Pathogenesis of Lewy Body Disorders. Front Aging Neurosci 2021; 13:690293. [PMID: 34248606 PMCID: PMC8267936 DOI: 10.3389/fnagi.2021.690293] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Accepted: 05/24/2021] [Indexed: 12/16/2022] Open
Abstract
Lewy Body Disorders (LBDs) lie within the spectrum of age-related neurodegenerative diseases now frequently categorized as the synucleinopathies. LBDs are considered to be among the second most common form of neurodegenerative dementias after Alzheimer's disease. They are progressive conditions with variable clinical symptoms embodied within specific cognitive and behavioral disorders. There are currently no effective treatments for LBDs. LBDs are histopathologically characterized by the presence of abnormal neuronal inclusions commonly known as Lewy Bodies (LBs) and extracellular Lewy Neurites (LNs). The inclusions predominantly comprise aggregates of alpha-synuclein (aSyn). It has been proposed that post-translational modifications (PTMs) such as aSyn phosphorylation, ubiquitination SUMOylation, Nitration, o-GlcNacylation, and Truncation play important roles in the formation of toxic forms of the protein, which consequently facilitates the formation of these inclusions. This review focuses on the role of different PTMs in aSyn in the pathogenesis of LBDs. We highlight how these PTMs interact with aSyn to promote misfolding and aggregation and interplay with cell membranes leading to the potential functional and pathogenic consequences detected so far, and their involvement in the development of LBDs.
Collapse
Affiliation(s)
- Nelson de Oliveira Manzanza
- Translational and Clinical Research Institute, Campus for Ageing and Vitality, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Lucia Sedlackova
- Biosciences Institute, Campus for Ageing and Vitality, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Raj N. Kalaria
- Translational and Clinical Research Institute, Campus for Ageing and Vitality, Newcastle University, Newcastle upon Tyne, United Kingdom
| |
Collapse
|
23
|
Youssef P, Kim WS, Halliday GM, Lewis SJG, Dzamko N. Comparison of Different Platform Immunoassays for the Measurement of Plasma Alpha-Synuclein in Parkinson's Disease Patients. JOURNAL OF PARKINSONS DISEASE 2021; 11:1761-1772. [PMID: 34151860 PMCID: PMC8609717 DOI: 10.3233/jpd-212694] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Background: The identification of reliable biomarkers in Parkinson’s disease (PD) would provide much needed diagnostic accuracy, a means of monitoring progression, objectively measuring treatment response, and potentially allowing patient stratification within clinical trials. Whilst the assessment of total alpha-synuclein in biofluids has been identified as a promising biomarker, conflicting trends in these levels across patient plasma samples relative to controls has limited its use. Different commercially available assay platforms that have been used to measure alpha-synuclein may contribute to different study outcomes. Objective: To compare different platform immunoassays for the measurement of total alpha-synuclein using the same plasma samples from 49 PD patients and 47 controls. Methods: Total plasma alpha-synuclein concentrations were assessed using the BioLegend, MesoScale Discovery, and Quanterix platform in plasma samples from PD patients and matched controls. Results: A significant increase in total plasma alpha-synuclein was observed in PD patients using the Biolegend (10%), Mesoscale Discovery (13%) and Quanterix (39%) assays. The Mesoscale Discovery and Quanterix assays showed the strongest correlations (r = 0.78, p < 0.0001) with each other, whilst the Quanterix platform demonstrated the lowest variation and highest effect size. Inclusion of age, sex and hemoglobin levels as covariates in the analysis of total alpha-synuclein improved the ability of all three immunoassays to detect a significant difference between patients and controls. Conclusion: All three immunoassays were sensitive enough to detect group level differences between PD patients and controls, with the largest effect size observed with the Quanterix assay. These results may help inform assay choices in ongoing clinical trials.
Collapse
Affiliation(s)
- Priscilla Youssef
- School of Medical Sciences, Faculty of Medicine and Health and the Brain and Mind Centre, University of Sydney, Camperdown, NSW, Australia
| | - Woojin S Kim
- School of Medical Sciences, Faculty of Medicine and Health and the Brain and Mind Centre, University of Sydney, Camperdown, NSW, Australia
| | - Glenda M Halliday
- School of Medical Sciences, Faculty of Medicine and Health and the Brain and Mind Centre, University of Sydney, Camperdown, NSW, Australia
| | - Simon J G Lewis
- School of Medical Sciences, Faculty of Medicine and Health and the Brain and Mind Centre, University of Sydney, Camperdown, NSW, Australia
| | - Nicolas Dzamko
- School of Medical Sciences, Faculty of Medicine and Health and the Brain and Mind Centre, University of Sydney, Camperdown, NSW, Australia
| |
Collapse
|
24
|
Du T, Wang L, Liu W, Zhu G, Chen Y, Zhang J. Biomarkers and the Role of α-Synuclein in Parkinson's Disease. Front Aging Neurosci 2021; 13:645996. [PMID: 33833675 PMCID: PMC8021696 DOI: 10.3389/fnagi.2021.645996] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2020] [Accepted: 03/05/2021] [Indexed: 12/13/2022] Open
Abstract
Parkinson's disease (PD) is a progressive neurodegenerative disorder characterized by the presence of α-synuclein (α-Syn)-rich Lewy bodies (LBs) and the preferential loss of dopaminergic (DA) neurons in the substantia nigra (SN) pars compacta (SNpc). However, the widespread involvement of other central nervous systems (CNS) structures and peripheral tissues is now widely documented. The onset of the molecular and cellular neuropathology of PD likely occurs decades before the onset of the motor symptoms characteristic of PD, so early diagnosis of PD and adequate tracking of disease progression could significantly improve outcomes for patients. Because the clinical diagnosis of PD is challenging, misdiagnosis is common, which highlights the need for disease-specific and early-stage biomarkers. This review article aims to summarize useful biomarkers for the diagnosis of PD, as well as the biomarkers used to monitor disease progression. This review article describes the role of α-Syn in PD and how it could potentially be used as a biomarker for PD. Also, preclinical and clinical investigations encompassing genetics, immunology, fluid and tissue, imaging, as well as neurophysiology biomarkers are discussed. Knowledge of the novel biomarkers for preclinical detection and clinical evaluation will contribute to a deeper understanding of the disease mechanism, which should more effectively guide clinical applications.
Collapse
Affiliation(s)
- Tingting Du
- Department of Functional Neurosurgery, Beijing Neurosurgical Institute, Capital Medical University, Beijing, China
| | - Le Wang
- Molecular Biology Laboratory for Neuropsychiatric Diseases, Department of Neurobiology, Beijing Institute of Brain Disorders, Capital Medical University, Beijing, China
| | - Weijin Liu
- Key Laboratory for Neurodegenerative Disease of the Ministry of Education, Key Laboratory of Neural Regeneration and Repair, Beijing Key Laboratory on Parkinson’s Disease, Department of Neurobiology, School of Basic Medical Sciences, Capital Medical University, Beijing, China
| | - Guanyu Zhu
- Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Beijing, China
| | - Yingchuan Chen
- Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Beijing, China
| | - Jianguo Zhang
- Department of Functional Neurosurgery, Beijing Neurosurgical Institute, Capital Medical University, Beijing, China
- Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Beijing, China
- Beijing Key Laboratory of Neurostimulation, Beijing Municipal Science and Technology Commission, Beijing, China
| |
Collapse
|
25
|
Manne S, Kondru N, Jin H, Anantharam V, Huang X, Kanthasamy A, Kanthasamy AG. α-Synuclein real-time quaking-induced conversion in the submandibular glands of Parkinson's disease patients. Mov Disord 2019; 35:268-278. [PMID: 31758740 DOI: 10.1002/mds.27907] [Citation(s) in RCA: 91] [Impact Index Per Article: 18.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2019] [Revised: 10/08/2019] [Accepted: 10/11/2019] [Indexed: 01/01/2023] Open
Abstract
BACKGROUND Identification of a peripheral biomarker is a major roadblock in the diagnosis of PD. Immunohistological identification of p-serine 129 α-synuclein in the submandibular gland tissues of PD patients has been recently reported. OBJECTIVE We report on a proof-of-principle study for using an ultra-sensitive and specific, real-time quaking-induced conversion assay to detect pathological α-synuclein in the submandibular gland tissues of PD patients. METHODS The α-synuclein real-time quaking-induced conversion assay was used to detect and quantify pathological α-synuclein levels in PD, incidental Lewy body disease, and control submandibular gland tissues as well as in formalin-fixed paraffin-embedded sections. RESULTS We determined the quantitative seeding kinetics of pathological α-synuclein present in submandibular gland tissues from autopsied subjects using the α-synuclein real-time quaking-induced conversion assay. A total of 32 cases comprising 13 PD, 3 incidental Lewy body disease, and 16 controls showed 100% sensitivity and 94% specificity. Interestingly, both PD and incidental Lewy body disease tissues showed 100% concordance for elevated levels of pathological α-synuclein seeding activity compared to control tissues. End-point dilution kinetic analyses revealed that the submandibular gland had a wide dynamic range of pathological α-synuclein seeding activity. CONCLUSIONS Our results are the first to demonstrate the utility of using the real-time quaking-induced conversion assay on peripherally accessible submandibular gland tissues and formalin-fixed paraffin-embedded tissue sections to detect PD-related pathological changes with high sensitivity and specificity. Additionally, the detection of seeding activity from incidental Lewy body disease cases containing immunohistochemically undetected pathological α-synuclein demonstrates the α-synuclein real-time quaking-induced conversion assay's potential utility for identifying prodromal PD in submandibular gland tissues. © 2019 International Parkinson and Movement Disorder Society.
Collapse
Affiliation(s)
- Sireesha Manne
- Department of Biomedical Sciences, Parkinson's Disorder Research Program, Iowa Center for Advanced Neurotoxicology, Iowa State University, Ames, Iowa, USA
| | - Naveen Kondru
- Department of Biomedical Sciences, Parkinson's Disorder Research Program, Iowa Center for Advanced Neurotoxicology, Iowa State University, Ames, Iowa, USA
| | - Huajun Jin
- Department of Biomedical Sciences, Parkinson's Disorder Research Program, Iowa Center for Advanced Neurotoxicology, Iowa State University, Ames, Iowa, USA
| | - Vellareddy Anantharam
- Department of Biomedical Sciences, Parkinson's Disorder Research Program, Iowa Center for Advanced Neurotoxicology, Iowa State University, Ames, Iowa, USA
| | - Xuemei Huang
- Department of Neurology and Pharmacology, Neurosurgery, Radiology, and Kinesiology, Penn State Milton S. Hershey Medical Center, Hershey, Pennsylvania, USA
| | - Arthi Kanthasamy
- Department of Biomedical Sciences, Parkinson's Disorder Research Program, Iowa Center for Advanced Neurotoxicology, Iowa State University, Ames, Iowa, USA
| | - Anumantha G Kanthasamy
- Department of Biomedical Sciences, Parkinson's Disorder Research Program, Iowa Center for Advanced Neurotoxicology, Iowa State University, Ames, Iowa, USA
| |
Collapse
|