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Mercado G, Kaeufer C, Richter F, Peelaerts W. Infections in the Etiology of Parkinson's Disease and Synucleinopathies: A Renewed Perspective, Mechanistic Insights, and Therapeutic Implications. JOURNAL OF PARKINSON'S DISEASE 2024:JPD240195. [PMID: 39331109 DOI: 10.3233/jpd-240195] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/28/2024]
Abstract
Increasing evidence suggests a potential role for infectious pathogens in the etiology of synucleinopathies, a group of age-related neurodegenerative disorders including Parkinson's disease (PD), multiple system atrophy and dementia with Lewy bodies. In this review, we discuss the link between infections and synucleinopathies from a historical perspective, present emerging evidence that supports this link, and address current research challenges with a focus on neuroinflammation. Infectious pathogens can elicit a neuroinflammatory response and modulate genetic risk in PD and related synucleinopathies. The mechanisms of how infections might be linked with synucleinopathies as well as the overlap between the immune cellular pathways affected by virulent pathogens and disease-related genetic risk factors are discussed. Here, an important role for α-synuclein in the immune response against infections is emerging. Critical methodological and knowledge gaps are addressed, and we provide new future perspectives on how to address these gaps. Understanding how infections and neuroinflammation influence synucleinopathies will be essential for the development of early diagnostic tools and novel therapies.
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Affiliation(s)
- Gabriela Mercado
- Division of Neurobiology, Department of Psychiatry, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Christopher Kaeufer
- Center for Systems Neuroscience, Hannover, Germany
- Department of Pharmacology, Toxicology and Pharmacy, University of Veterinary Medicine Hannover, Hannover, Germany
| | - Franziska Richter
- Department of Pharmacology, Toxicology and Pharmacy, University of Veterinary Medicine Hannover, Hannover, Germany
| | - Wouter Peelaerts
- Laboratory for Virology and Gene Therapy, Department of Pharmacy and Pharmaceutical Sciences, KU Leuven, Leuven, Belgium
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2
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Strobel S, Sian-Hulsmann J, Tappe D, Jellinger K, Riederer P, Monoranu CM. Postencephalitic Parkinsonism: Unique Pathological and Clinical Features-Preliminary Data. Cells 2024; 13:1511. [PMID: 39329695 PMCID: PMC11430219 DOI: 10.3390/cells13181511] [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: 07/09/2024] [Revised: 08/29/2024] [Accepted: 09/04/2024] [Indexed: 09/28/2024] Open
Abstract
Postencephalitic parkinsonism (PEP) is suggested to show a virus-induced pathology, which is different from classical idiopathic Parkinson's disease (PD) as there is no α-synuclein/Lewy body pathology. However, PEP shows a typical clinical representation of motor disturbances. In addition, compared to PD, there is no iron-induced pathology. The aim of this preliminary study was to compare PEP with PD regarding iron-induced pathology, using histochemistry methods on paraffin-embedded post-mortem brain tissue. In the PEP group, iron was not seen, except for one case with sparse perivascular depositions. Rather, PEP offers a pathology related to tau-protein/neurofibrillary tangles, with mild to moderate memory deficits only. It is assumed that this virus-induced pathology is due to immunological dysfunctions causing (neuro)inflammation-induced neuronal network disturbances as events that trigger clinical parkinsonism. The absence of iron deposits implies that PEP cannot be treated with iron chelators. The therapy with L-Dopa is also not an option, as L-Dopa only leads to an initial slight improvement in symptoms in isolated cases.
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Affiliation(s)
- Sabrina Strobel
- Institute of Pathology, Department of Neuropathology, University of Wuerzburg, 97080 Wuerzburg, Germany;
| | - Jeswinder Sian-Hulsmann
- Department of Medical Physiology, University of Nairobi, P.O. Box 30197, Nairobi 00100, Kenya;
| | - Dennis Tappe
- Bernhard Nocht Institute for Tropical Medicine, 20359 Hamburg, Germany;
| | - Kurt Jellinger
- Institute of Clinical Neurobiology, A-1150 Vienna, Austria;
| | - Peter Riederer
- Clinic and Policlinic for Psychiatry, Psychosomatics and Psychotherapy, University Hospital Wuerzburg, 97080 Wuerzburg, Germany;
- Department of Psychiatry, University of Southern Denmark, 5000 Odense, Denmark
| | - Camelia-Maria Monoranu
- Institute of Pathology, Department of Neuropathology, University of Wuerzburg, 97080 Wuerzburg, Germany;
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3
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Li W, Li JY. Overlaps and divergences between tauopathies and synucleinopathies: a duet of neurodegeneration. Transl Neurodegener 2024; 13:16. [PMID: 38528629 DOI: 10.1186/s40035-024-00407-y] [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: 11/07/2023] [Accepted: 02/28/2024] [Indexed: 03/27/2024] Open
Abstract
Proteinopathy, defined as the abnormal accumulation of proteins that eventually leads to cell death, is one of the most significant pathological features of neurodegenerative diseases. Tauopathies, represented by Alzheimer's disease (AD), and synucleinopathies, represented by Parkinson's disease (PD), show similarities in multiple aspects. AD manifests extrapyramidal symptoms while dementia is also a major sign of advanced PD. We and other researchers have sequentially shown the cross-seeding phenomenon of α-synuclein (α-syn) and tau, reinforcing pathologies between synucleinopathies and tauopathies. The highly overlapping clinical and pathological features imply shared pathogenic mechanisms between the two groups of disease. The diagnostic and therapeutic strategies seemingly appropriate for one distinct neurodegenerative disease may also apply to a broader spectrum. Therefore, a clear understanding of the overlaps and divergences between tauopathy and synucleinopathy is critical for unraveling the nature of the complicated associations among neurodegenerative diseases. In this review, we discuss the shared and diverse characteristics of tauopathies and synucleinopathies from aspects of genetic causes, clinical manifestations, pathological progression and potential common therapeutic approaches targeting the pathology, in the aim to provide a timely update for setting the scheme of disease classification and provide novel insights into the therapeutic development for neurodegenerative diseases.
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Affiliation(s)
- Wen Li
- Health Sciences Institute, Key Laboratory of Major Chronic Diseases of Nervous System of Liaoning Province, China Medical University, Shenyang, 110122, China
| | - Jia-Yi Li
- Health Sciences Institute, Key Laboratory of Major Chronic Diseases of Nervous System of Liaoning Province, China Medical University, Shenyang, 110122, China.
- Neural Plasticity and Repair Unit, Department of Experimental Medical Science, Wallenberg Neuroscience Center, Lund University, BMC A10, 22184, Lund, Sweden.
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Eser P, Kocabicak E, Bekar A, Temel Y. The interplay between neuroinflammatory pathways and Parkinson's disease. Exp Neurol 2024; 372:114644. [PMID: 38061555 DOI: 10.1016/j.expneurol.2023.114644] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2023] [Revised: 11/25/2023] [Accepted: 12/01/2023] [Indexed: 01/03/2024]
Abstract
Parkinson's disease, a progressive neurodegenerative disorder predominantly affecting elderly, is marked by the gradual degeneration of the nigrostriatal dopaminergic pathway, culminating in neuronal loss within the substantia nigra pars compacta (SNpc) and dopamine depletion. At the molecular level, neuronal loss in the SNpc has been attributed to factors including neuroinflammation, impaired protein homeostasis, as well as mitochondrial dysfunction and the resulting oxidative stress. This review focuses on the interplay between neuroinflammatory pathways and Parkinson's disease, drawing insights from current literature.
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Affiliation(s)
- Pinar Eser
- Bursa Uludag University School of Medicine, Department of Neurosurgery, Bursa, Turkey.
| | - Ersoy Kocabicak
- Ondokuz Mayis University, Health Practise and Research Hospital, Neuromodulation Center, Samsun, Turkey
| | - Ahmet Bekar
- Bursa Uludag University School of Medicine, Department of Neurosurgery, Bursa, Turkey
| | - Yasin Temel
- Department of Neurosurgery, Maastricht University Medical Center, Maastricht, the Netherlands
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5
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Chu Y, Hirst WD, Federoff HJ, Harms AS, Stoessl AJ, Kordower JH. Nigrostriatal tau pathology in parkinsonism and Parkinson's disease. Brain 2024; 147:444-457. [PMID: 38006313 PMCID: PMC10834249 DOI: 10.1093/brain/awad388] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2023] [Revised: 10/11/2023] [Accepted: 11/02/2023] [Indexed: 11/27/2023] Open
Abstract
While Parkinson's disease remains clinically defined by cardinal motor symptoms resulting from nigrostriatal degeneration, it is now appreciated that the disease commonly consists of multiple pathologies, but it is unclear where these co-pathologies occur early in disease and whether they are responsible for the nigrostriatal degeneration. For the past number of years, we have been studying a well-characterized cohort of subjects with motor impairment that we have termed mild motor deficits. Motor deficits were determined on a modified and validated Unified Parkinson's Disease Rating Scale III but were insufficient in degree to diagnose Parkinson's disease. However, in our past studies, cases in this cohort had a selection bias, as both a clinical syndrome in between no motor deficits and Parkinson's disease, plus nigral Lewy pathology as defined post-mortem, were required for inclusion. Therefore, in the current study, we only based inclusion on the presence of a clinical phenotype with mild motor impairment insufficient to diagnose Parkinson's disease. Then, we divided this group further based upon whether or not subjects had a synucleinopathy in the nigrostriatal system. Here we demonstrate that loss of nigral dopaminergic neurons, loss of putamenal dopaminergic innervation and loss of the tyrosine hydroxylase-phenotype in the substantia nigra and putamen occur equally in mild motor deficit groups with and without nigral alpha-synuclein aggregates. Indeed, the common feature of these two groups is that both have similar degrees of AT8 positive phosphorylated tau, a pathology not seen in the nigrostriatal system of age-matched controls. These findings were confirmed with early (tau Ser208 phosphorylation) and late (tau Ser396/Ser404 phosphorylation) tau markers. This suggests that the initiation of nigrostriatal dopaminergic neurodegeneration occurs independently of alpha-synuclein aggregation and can be tau mediated.
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Affiliation(s)
- Yaping Chu
- ASU-Banner Neurodegenerative Disease Research Center, Arizona State University, Tempe, AZ 85281, USA
| | - Warren D Hirst
- Neurodegenerative Diseases Research Unit, Biogen, Cambridge, MA 02142, USA
- Aligning Science Across Parkinson’s (ASAP) Collaborative Research Network, Chevy Chase, MD 20815, USA
| | - Howard J Federoff
- Neurology, School of Medicine, Georgetown University Medical Center, Washington, DC 20007, USA
| | - Ashley S Harms
- Department of Neurology, University of Alabama at Birmingham, Birmingham, AL 35294, USA
- Aligning Science Across Parkinson’s (ASAP) Collaborative Research Network, Chevy Chase, MD 20815, USA
| | - A Jon Stoessl
- Pacific Parkinson’s Research Centre and Djavad Mowafaghian Centre for Brain Health, University of British Columbia, Vancouver, BC V6T 1Z3, Canada
| | - Jeffrey H Kordower
- ASU-Banner Neurodegenerative Disease Research Center, Arizona State University, Tempe, AZ 85281, USA
- Aligning Science Across Parkinson’s (ASAP) Collaborative Research Network, Chevy Chase, MD 20815, USA
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6
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Sian-Hulsmann J, Riederer P. Virus-induced brain pathology and the neuroinflammation-inflammation continuum: the neurochemists view. J Neural Transm (Vienna) 2024:10.1007/s00702-023-02723-5. [PMID: 38261034 DOI: 10.1007/s00702-023-02723-5] [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: 09/21/2023] [Accepted: 11/18/2023] [Indexed: 01/24/2024]
Abstract
Fascinatingly, an abundance of recent studies has subscribed to the importance of cytotoxic immune mechanisms that appear to increase the risk/trigger for many progressive neurodegenerative disorders, including Parkinson's disease (PD), Alzheimer's disease (AD), amyotrophic lateral sclerosis, and multiple sclerosis. Events associated with the neuroinflammatory cascades, such as ageing, immunologic dysfunction, and eventually disruption of the blood-brain barrier and the "cytokine storm", appear to be orchestrated mainly through the activation of microglial cells and communication with the neurons. The inflammatory processes prompt cellular protein dyshomeostasis. Parkinson's and Alzheimer's disease share a common feature marked by characteristic pathological hallmarks of abnormal neuronal protein accumulation. These Lewy bodies contain misfolded α-synuclein aggregates in PD or in the case of AD, they are Aβ deposits and tau-containing neurofibrillary tangles. Subsequently, these abnormal protein aggregates further elicit neurotoxic processes and events which contribute to the onset of neurodegeneration and to its progression including aggravation of neuroinflammation. However, there is a caveat for exclusively linking neuroinflammation with neurodegeneration, since it's highly unlikely that immune dysregulation is the only factor that contributes to the manifestation of many of these neurodegenerative disorders. It is unquestionably a complex interaction with other factors such as genetics, age, and environment. This endorses the "multiple hit hypothesis". Consequently, if the host has a genetic susceptibility coupled to an age-related weakened immune system, this makes them more susceptible to the virus/bacteria-related infection. This may trigger the onset of chronic cytotoxic neuroinflammatory processes leading to protein dyshomeostasis and accumulation, and finally, these events lead to neuronal destruction. Here, we differentiate "neuroinflammation" and "inflammation" with regard to the involvement of the blood-brain barrier, which seems to be intact in the case of neuroinflammation but defect in the case of inflammation. There is a neuroinflammation-inflammation continuum with regard to virus-induced brain affection. Therefore, we propose a staging of this process, which might be further developed by adding blood- and CSF parameters, their stage-dependent composition and stage-dependent severeness grade. If so, this might be suitable to optimise therapeutic strategies to fight brain neuroinflammation in its beginning and avoid inflammation at all.
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Affiliation(s)
- Jeswinder Sian-Hulsmann
- Department of Human Anatomy and Medical Physiology, University of Nairobi, P.O. Box 30197, Nairobi, 00100, Kenya
| | - Peter Riederer
- University Hospital Wuerzburg, Clinic and Policlinic for Psychiatry, Psychosomatics and Psychotherapy Margarete-Höppel-Platz 1, 97080, Würzburg, Germany.
- Department of Psychiatry, University of Southern Denmark, Winslows Vey 18, 5000, Odense, J.B, Denmark.
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Langworth-Green C, Patel S, Jaunmuktane Z, Jabbari E, Morris H, Thom M, Lees A, Hardy J, Zandi M, Duff K. Chronic effects of inflammation on tauopathies. Lancet Neurol 2023; 22:430-442. [PMID: 37059510 DOI: 10.1016/s1474-4422(23)00038-8] [Citation(s) in RCA: 17] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Revised: 01/20/2023] [Accepted: 01/27/2023] [Indexed: 04/16/2023]
Abstract
Tauopathies are a heterogeneous group of neurodegenerative disorders that are characterised by the aggregation of the microtubule-associated protein tau into filamentous inclusions within neurons and glia. Alzheimer's disease is the most prevalent tauopathy. Despite years of intense research efforts, developing disease-modifying interventions for these disorders has been very challenging. The detrimental role that chronic inflammation plays in the pathogenesis of Alzheimer's disease is increasingly recognised; however, it is largely ascribed to the accumulation of amyloid β, leaving the effect of chronic inflammation on tau pathology and neurofibrillary tangle-related pathways greatly overlooked. Tau pathology can independently arise secondary to a range of triggers that are each associated with inflammatory processes, including infection, repetitive mild traumatic brain injury, seizure activity, and autoimmune disease. A greater understanding of the chronic effects of inflammation on the development and progression of tauopathies could help forge a path for the establishment of effective immunomodulatory disease-modifying interventions for clinical use.
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Affiliation(s)
| | - Saisha Patel
- UK Dementia Research Institute, University College London, London, UK
| | - Zane Jaunmuktane
- Department of Clinical and Movement Neurosciences, University College London, London, UK; Queen Square Brain Bank for Neurological Disorders, University College London, London, UK; Division of Neuropathology, University College London, London, UK; National Hospital for Neurology and Neurosurgery, London, UK
| | - Edwin Jabbari
- Department of Clinical and Movement Neurosciences, University College London, London, UK; National Hospital for Neurology and Neurosurgery, London, UK; Department of Neurology, Royal Free Hospital, London, UK
| | - Huw Morris
- Department of Clinical and Movement Neurosciences, University College London, London, UK; National Hospital for Neurology and Neurosurgery, London, UK; Department of Neurology, Royal Free Hospital, London, UK
| | - Maria Thom
- Division of Neuropathology, University College London, London, UK; Department of Clinical and Experimental Epilepsy, University College London, London, UK
| | - Andrew Lees
- Department of Clinical and Movement Neurosciences, University College London, London, UK; Reta Lila Weston Institute, University College London, London, UK
| | - John Hardy
- UK Dementia Research Institute, University College London, London, UK; Reta Lila Weston Institute, University College London, London, UK; Department of Neurodegenerative Disease, University College London, London, UK
| | - Michael Zandi
- Department of Neuroinflammation, UCL Queen Square Institute of Neurology, University College London, London, UK; National Hospital for Neurology and Neurosurgery, London, UK
| | - Karen Duff
- UK Dementia Research Institute, University College London, London, UK.
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8
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Riederer P, Nagatsu T, Youdim MBH, Wulf M, Dijkstra JM, Sian-Huelsmann J. Lewy bodies, iron, inflammation and neuromelanin: pathological aspects underlying Parkinson's disease. J Neural Transm (Vienna) 2023; 130:627-646. [PMID: 37062012 PMCID: PMC10121516 DOI: 10.1007/s00702-023-02630-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Accepted: 03/29/2023] [Indexed: 04/17/2023]
Abstract
Since the description of some peculiar symptoms by James Parkinson in 1817, attempts have been made to define its cause or at least to enlighten the pathology of "Parkinson's disease (PD)." The vast majority of PD subtypes and most cases of sporadic PD share Lewy bodies (LBs) as a characteristic pathological hallmark. However, the processes underlying LBs generation and its causal triggers are still unknown. ɑ-Synuclein (ɑ-syn, encoded by the SNCA gene) is a major component of LBs, and SNCA missense mutations or duplications/triplications are causal for rare hereditary forms of PD. Thus, it is imperative to study ɑ-syn protein and its pathology, including oligomerization, fibril formation, aggregation, and spreading mechanisms. Furthermore, there are synergistic effects in the underlying pathogenic mechanisms of PD, and multiple factors-contributing with different ratios-appear to be causal pathological triggers and progression factors. For example, oxidative stress, reduced antioxidative capacity, mitochondrial dysfunction, and proteasomal disturbances have each been suggested to be causal for ɑ-syn fibril formation and aggregation and to contribute to neuroinflammation and neural cell death. Aging is also a major risk factor for PD. Iron, as well as neuromelanin (NM), show age-dependent increases, and iron is significantly increased in the Parkinsonian substantia nigra (SN). Iron-induced pathological mechanisms include changes of the molecular structure of ɑ-syn. However, more recent PD research demonstrates that (i) LBs are detected not only in dopaminergic neurons and glia but in various neurotransmitter systems, (ii) sympathetic nerve fibres degenerate first, and (iii) at least in "brain-first" cases dopaminergic deficiency is evident before pathology induced by iron and NM. These recent findings support that the ɑ-syn/LBs pathology as well as iron- and NM-induced pathology in "brain-first" cases are important facts of PD pathology and via their interaction potentiate the disease process in the SN. As such, multifactorial toxic processes posted on a personal genetic risk are assumed to be causal for the neurodegenerative processes underlying PD. Differences in ratios of multiple factors and their spatiotemporal development, and the fact that common triggers of PD are hard to identify, imply the existence of several phenotypical subtypes, which is supported by arguments from both the "bottom-up/dual-hit" and "brain-first" models. Therapeutic strategies are necessary to avoid single initiation triggers leading to PD.
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Affiliation(s)
- Peter Riederer
- Clinic and Policlinic for Psychiatry, Psychosomatics and Psychotherapy, University Hospital Wuerzburg, Margarete-Höppel-Platz 1, 97080, Würzburg, Germany.
- Department of Psychiatry, University of Southern Denmark Odense, J.B. Winslows Vey 18, 5000, Odense, Denmark.
| | - Toshiharu Nagatsu
- Center for Research Promotion and Support, School of Medicine, Fujita Health University, Toyoake, Aichi, 470-1192, Japan
| | | | - Max Wulf
- Medizinisches Proteom-Center, Medical Faculty, Ruhr-University Bochum, 44801, Bochum, Germany
- Medical Proteome Analysis, Center for Protein Diagnostics (PRODI), Ruhr-University Bochum, 44801, Bochum, Germany
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Mancini M, Natoli S, Gardoni F, Di Luca M, Pisani A. Dopamine Transmission Imbalance in Neuroinflammation: Perspectives on Long-Term COVID-19. Int J Mol Sci 2023; 24:ijms24065618. [PMID: 36982693 PMCID: PMC10056044 DOI: 10.3390/ijms24065618] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2023] [Revised: 03/09/2023] [Accepted: 03/13/2023] [Indexed: 03/17/2023] Open
Abstract
Dopamine (DA) is a key neurotransmitter in the basal ganglia, implicated in the control of movement and motivation. Alteration of DA levels is central in Parkinson’s disease (PD), a common neurodegenerative disorder characterized by motor and non-motor manifestations and deposition of alpha-synuclein (α-syn) aggregates. Previous studies have hypothesized a link between PD and viral infections. Indeed, different cases of parkinsonism have been reported following COVID-19. However, whether SARS-CoV-2 may trigger a neurodegenerative process is still a matter of debate. Interestingly, evidence of brain inflammation has been described in postmortem samples of patients infected by SARS-CoV-2, which suggests immune-mediated mechanisms triggering the neurological sequelae. In this review, we discuss the role of proinflammatory molecules such as cytokines, chemokines, and oxygen reactive species in modulating DA homeostasis. Moreover, we review the existing literature on the possible mechanistic interplay between SARS-CoV-2-mediated neuroinflammation and nigrostriatal DAergic impairment, and the cross-talk with aberrant α-syn metabolism.
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Affiliation(s)
- Maria Mancini
- Department of Brain and Behavioral Sciences, University of Pavia, 27100 Pavia, Italy;
- IRCCS Mondino Foundation, 27100 Pavia, Italy
| | - Silvia Natoli
- Department of Clinical Science and Translational Medicine, University of Rome Tor Vergata, 00133 Rome, Italy;
- IRCCS Maugeri Pavia, 27100 Pavia, Italy
| | - Fabrizio Gardoni
- Department of Pharmacological and Biomolecular Sciences “Rodolfo Paoletti”, University of Milan, 20133 Milan, Italy; (F.G.); (M.D.L.)
| | - Monica Di Luca
- Department of Pharmacological and Biomolecular Sciences “Rodolfo Paoletti”, University of Milan, 20133 Milan, Italy; (F.G.); (M.D.L.)
| | - Antonio Pisani
- Department of Brain and Behavioral Sciences, University of Pavia, 27100 Pavia, Italy;
- IRCCS Mondino Foundation, 27100 Pavia, Italy
- Correspondence: ; Tel.: +39-0382-380-247
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Leta V, Urso D, Batzu L, Lau YH, Mathew D, Boura I, Raeder V, Falup-Pecurariu C, van Wamelen D, Ray Chaudhuri K. Viruses, parkinsonism and Parkinson's disease: the past, present and future. J Neural Transm (Vienna) 2022; 129:1119-1132. [PMID: 36036863 PMCID: PMC9422946 DOI: 10.1007/s00702-022-02536-y] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2022] [Accepted: 08/01/2022] [Indexed: 01/01/2023]
Abstract
Parkinsonism secondary to viral infections is not an uncommon occurrence and has been brought under the spotlight with the spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. A variety of viruses have been described with a potential of inducing or contributing to the occurrence of parkinsonism and Parkinson's disease (PD), although the relationship between the two remains a matter of debate originating with the description of encephalitis lethargica in the aftermath of the Spanish flu in 1918. While some viral infections have been linked to an increased risk for the development of PD, others seem to have a causal link with the occurrence of parkinsonism. Here, we review the currently available evidence on viral-induced parkinsonism with a focus on potential pathophysiological mechanisms and clinical features. We also review the evidence on viral infections as a risk factor for developing PD and the link between SARS-CoV-2 and parkinsonism, which might have important implications for future research and treatments.
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Affiliation(s)
- Valentina Leta
- Department of Basic and Clinical Neurosciences, Institute of Psychiatry, Psychology & Neuroscience, King's College London, Cutcombe Road, London, SE5 9RT, UK
- Parkinson's Foundation Centre of Excellence, King's College Hospital, London, SE5 9RS, UK
| | - Daniele Urso
- Department of Basic and Clinical Neurosciences, Institute of Psychiatry, Psychology & Neuroscience, King's College London, Cutcombe Road, London, SE5 9RT, UK
- Department of Clinical Research in Neurology, Center for Neurodegenerative Diseases and the Aging Brain, University of Bari 'Aldo Moro', "Pia Fondazione Cardinale G. Panico", Tricase, Lecce, Italy
| | - Lucia Batzu
- Department of Basic and Clinical Neurosciences, Institute of Psychiatry, Psychology & Neuroscience, King's College London, Cutcombe Road, London, SE5 9RT, UK
- Parkinson's Foundation Centre of Excellence, King's College Hospital, London, SE5 9RS, UK
| | - Yue Hui Lau
- Department of Basic and Clinical Neurosciences, Institute of Psychiatry, Psychology & Neuroscience, King's College London, Cutcombe Road, London, SE5 9RT, UK
- Parkinson's Foundation Centre of Excellence, King's College Hospital, London, SE5 9RS, UK
| | - Donna Mathew
- Department of Basic and Clinical Neurosciences, Institute of Psychiatry, Psychology & Neuroscience, King's College London, Cutcombe Road, London, SE5 9RT, UK
- Parkinson's Foundation Centre of Excellence, King's College Hospital, London, SE5 9RS, UK
| | - Iro Boura
- School of Medicine, University of Crete, Heraklion, Crete, Greece
- Department of Neurology, University Hospital of Heraklion, Heraklion, Crete, Greece
| | - Vanessa Raeder
- Department of Basic and Clinical Neurosciences, Institute of Psychiatry, Psychology & Neuroscience, King's College London, Cutcombe Road, London, SE5 9RT, UK
- Parkinson's Foundation Centre of Excellence, King's College Hospital, London, SE5 9RS, UK
- Department of Neurology, Technical University Dresden, Dresden, Germany
| | | | - Daniel van Wamelen
- Department of Basic and Clinical Neurosciences, Institute of Psychiatry, Psychology & Neuroscience, King's College London, Cutcombe Road, London, SE5 9RT, UK
- Parkinson's Foundation Centre of Excellence, King's College Hospital, London, SE5 9RS, UK
- Department of Neurology, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Centre, Nijmegen, The Netherlands
| | - K Ray Chaudhuri
- Department of Basic and Clinical Neurosciences, Institute of Psychiatry, Psychology & Neuroscience, King's College London, Cutcombe Road, London, SE5 9RT, UK.
- Parkinson's Foundation Centre of Excellence, King's College Hospital, London, SE5 9RS, UK.
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11
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Kovacs GG, Ghetti B, Goedert M. Classification of Diseases with Accumulation of Tau Protein. Neuropathol Appl Neurobiol 2022; 48:e12792. [PMID: 35064600 PMCID: PMC9352145 DOI: 10.1111/nan.12792] [Citation(s) in RCA: 34] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Accepted: 01/07/2022] [Indexed: 11/28/2022]
Affiliation(s)
- Gabor G Kovacs
- Tanz Centre for Research in Neurodegenerative Disease and Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada.,Laboratory Medicine Program & Krembil Brain Institute, University Health Network, Toronto, Ontario, Canada
| | - Bernardino Ghetti
- Department of Pathology and Laboratory Medicine, Indiana University School of Medicine, Indiana, USA
| | - Michel Goedert
- MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge, UK
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12
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No Metagenomic Evidence of Causative Viral Pathogens in Postencephalitic Parkinsonism Following Encephalitis Lethargica. Microorganisms 2021; 9:microorganisms9081716. [PMID: 34442795 PMCID: PMC8398509 DOI: 10.3390/microorganisms9081716] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2021] [Revised: 08/08/2021] [Accepted: 08/09/2021] [Indexed: 12/24/2022] Open
Abstract
Postencephalitic parkinsonism (PEP) is a disease of unknown etiology and pathophysiology following encephalitis lethargica (EL), an acute-onset polioencephalitis of cryptic cause in the 1920s. PEP is a tauopathy with multisystem neuronal loss and gliosis, clinically characterized by bradykinesia, rigidity, rest tremor, and oculogyric crises. Though a viral cause of EL is likely, past polymerase chain reaction-based investigations in the etiology of both PEP and EL were negative. PEP might be caused directly by an unknown viral pathogen or the consequence of a post-infectious immunopathology. The development of metagenomic next-generation sequencing in conjunction with bioinformatic techniques has generated a broad-range tool for the detection of unknown pathogens in the recent past. Retrospective identification and characterization of pathogens responsible for past infectious diseases can be successfully performed with formalin-fixed paraffin-embedded (FFPE) tissue samples. In this study, we analyzed 24 FFPE brain samples from six patients with PEP by unbiased metagenomic next-generation sequencing. Our results show that no evidence for the presence of a specific or putative (novel) viral pathogen was found, suggesting a likely post-infectious immune-mediated etiology of PEP.
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13
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Danics K, Forrest SL, Kapas I, Erber I, Schmid S, Törő K, Majtenyi K, Kovacs GG. Neurodegenerative proteinopathies associated with neuroinfections. J Neural Transm (Vienna) 2021; 128:1551-1566. [PMID: 34223998 PMCID: PMC8255726 DOI: 10.1007/s00702-021-02371-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2021] [Accepted: 06/20/2021] [Indexed: 01/23/2023]
Abstract
Infectious agents, including viruses and bacteria, are proposed to be involved in the pathogenesis of Alzheimer’s disease (AD). According to this hypothesis, these agents have capacity to evade the host immune system leading to chronic infection, inflammation, and subsequent deposition of Aβ and phosphorylated-tau in the brain. Co-existing proteinopathies and age-related pathologies are common in AD and the brains of elderly individuals, but whether these are also related to neuroinfections remain to be established. This study determined the prevalence and distribution of neurodegenerative proteinopathies in patients with infection-induced acute or chronic inflammation associated with herpes simplex virus (HSV) encephalitis (n = 13) and neurosyphilis (n = 23). The mean age at death in HSV patients was 53 ± 12 years (range 24–65 years) and survival was 9 days–6 years following initial infection. The mean age at death and survival in neurosyphilis patients was 60 ± 15 years (range 36–86 years) and 1–5 years, respectively. Neuronal tau-immunoreactivity and neurites were observed in 8 HSV patients and 19 neurosyphilis patients, and in approximately half of these, this was found in regions associated with inflammation and expanding beyond regions expected from the Braak stage of neurofibrillary degeneration. Five neurosyphilis patients had cortical ageing-related tau astrogliopathy. Aβ-plaques were found in 4 HSV patients and 11 neurosyphilis patients. Lewy bodies were observed in one HSV patient and two neurosyphilis patients. TDP-43 pathology was absent. These observations provide insights into deposition of neurodegenerative proteins in neuroinfections, which might have implications for COVID-19 patients with chronic and/or post-infectious neurological symptoms and encephalitis.
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Affiliation(s)
- Krisztina Danics
- Department of Forensic and Insurance Medicine, Semmelweis University, Budapest, Hungary.,Neuropathology and Prion Disease Reference Center, Department of Forensic and Insurance Medicine, Semmelweis University, Budapest, Hungary
| | - Shelley L Forrest
- Dementia Research Centre, School of Biomedical Sciences, Faculty of Medicine, Health and Human Sciences, Macquarie University, Sydney, Australia.,Faculty of Medicine and Health, School of Medical Sciences, University of Sydney, Sydney, Australia
| | - Istvan Kapas
- Department of Neurology, St. Janos Hospital, Budapest, Hungary
| | - Irene Erber
- Division of Neuropathology and Neurochemistry, Department of Neurology, Medical University of Vienna, Vienna, Austria
| | - Susanne Schmid
- Division of Neuropathology and Neurochemistry, Department of Neurology, Medical University of Vienna, Vienna, Austria
| | - Klára Törő
- Department of Forensic and Insurance Medicine, Semmelweis University, Budapest, Hungary
| | - Katalin Majtenyi
- Neuropathology and Prion Disease Reference Center, Department of Forensic and Insurance Medicine, Semmelweis University, Budapest, Hungary
| | - Gabor G Kovacs
- Tanz Centre for Research in Neurodegenerative Disease and Department of Laboratory Medicine and Pathobiology, University of Toronto, Krembil Discovery Tower, 60 Leonard Ave, Toronto, ON, M5T 0S8, Canada. .,Laboratory Medicine Program & Krembil Brain Institute, University Health Network, Toronto, ON, Canada.
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14
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Sian-Hulsmann J, Riederer P. The Nigral Coup in Parkinson's Disease by α-Synuclein and Its Associated Rebels. Cells 2021; 10:598. [PMID: 33803185 PMCID: PMC8000327 DOI: 10.3390/cells10030598] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2021] [Revised: 03/02/2021] [Accepted: 03/03/2021] [Indexed: 12/24/2022] Open
Abstract
The risk of Parkinson's disease increases with age. However, the etiology of the illness remains obscure. It appears highly likely that the neurodegenerative processes involve an array of elements that influence each other. In addition, genetic, endogenous, or exogenous toxins need to be considered as viable partners to the cellular degeneration. There is compelling evidence that indicate the key involvement of modified α-synuclein (Lewy bodies) at the very core of the pathogenesis of the disease. The accumulation of misfolded α-synuclein may be a consequence of some genetic defect or/and a failure of the protein clearance system. Importantly, α-synuclein pathology appears to be a common denominator for many cellular deleterious events such as oxidative stress, mitochondrial dysfunction, dopamine synaptic dysregulation, iron dyshomeostasis, and neuroinflammation. These factors probably employ a common apoptotic/or autophagic route in the final stages to execute cell death. The misfolded α-synuclein inclusions skillfully trigger or navigate these processes and thus amplify the dopamine neuron fatalities. Although the process of neuroinflammation may represent a secondary event, nevertheless, it executes a fundamental role in neurodegeneration. Some viral infections produce parkinsonism and exhibit similar characteristic neuropathological changes such as a modest brain dopamine deficit and α-synuclein pathology. Thus, viral infections may heighten the risk of developing PD. Alternatively, α-synuclein pathology may induce a dysfunctional immune system. Thus, sporadic Parkinson's disease is caused by multifactorial trigger factors and metabolic disturbances, which need to be considered for the development of potential drugs in the disorder.
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Affiliation(s)
- Jeswinder Sian-Hulsmann
- Department of Medical Physiology, University of Nairobi, P.O. Box 30197, 00100 Nairobi, Kenya
| | - Peter Riederer
- Clinic and Policlinic for Psychiatry, Psychosomatics and Psychotherapy Margarete-Hoeppel-Platz 1, University Hospital Wuerzburg, 97080 Wuerzburg, Germany;
- Department Psychiatry, University of Southern Denmark Odense, J.B. Winslows Vey 18, 5000 Odense, Denmark
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15
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Blanco-Palmero VA, Azcárate-Díaz FJ, Ruiz-Ortiz M, Laespada-García MI, Rábano-Suárez P, Méndez-Guerrero A, Aramendi-Ramos M, Eguiburu JL, Pérez-Rivilla A, Marchán-López A, Rubio-Fernández M, Carro E, González de la Aleja J. Serum and CSF alpha-synuclein levels do not change in COVID-19 patients with neurological symptoms. J Neurol 2021; 268:3116-3124. [PMID: 33606070 PMCID: PMC7892700 DOI: 10.1007/s00415-021-10444-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Revised: 02/02/2021] [Accepted: 02/03/2021] [Indexed: 01/08/2023]
Abstract
SARS-CoV-2 infection can associate diverse neurological manifestations. Several studies have provided proof to support the theory of neurotropic involvement of SARS-CoV-2. Alpha-synuclein has been described as a native antiviral factor within neurons, and upregulation of this protein can be seen in animals that suffered other neuroinvasive infections. To assess if increased expression of this protein takes place in COVID-19 patients with neurological symptoms, we analyzed serum total alpha-synuclein levels in three groups: seven COVID-19 patients with myoclonus, Parkinsonism and/or encephalopathy; thirteen age- and sex-matched COVID-19 patients without neurological involvement and eight age- and sex-matched healthy controls. We did not find differences among them. In a subset of four patients, the change in serum alpha-synuclein before and after the onset of neurological symptoms was not significant either. Cerebrospinal fluid alpha-synuclein levels were also similar between neurological COVID-19 and healthy controls. Overall, these results cannot support the hypothesis of alpha-synuclein upregulation in humans with neurological symptoms in COVID-19. Further research taking into account a larger group of COVID-19 patients including the whole spectrum of neurological manifestations and disease severity is needed.
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Affiliation(s)
- V A Blanco-Palmero
- Department of Neurology, Hospital Universitario 12 de Octubre, Avda. de Córdoba, s/n 28041, Madrid, Spain. .,Group of Neurodegenerative Diseases, Instituto de Investigación Hospital 12 de Octubre (i+12), Madrid, Spain. .,Networked Biomedical Research Center in Neurodegenerative Diseases (CIBERNED), Madrid, Spain.
| | - F J Azcárate-Díaz
- Department of Neurology, Hospital Universitario 12 de Octubre, Avda. de Córdoba, s/n 28041, Madrid, Spain
| | - M Ruiz-Ortiz
- Department of Neurology, Hospital Universitario 12 de Octubre, Avda. de Córdoba, s/n 28041, Madrid, Spain
| | - M I Laespada-García
- Department of Neurology, Hospital Universitario 12 de Octubre, Avda. de Córdoba, s/n 28041, Madrid, Spain
| | - P Rábano-Suárez
- Department of Neurology, Hospital Universitario 12 de Octubre, Avda. de Córdoba, s/n 28041, Madrid, Spain
| | - A Méndez-Guerrero
- Department of Neurology, Hospital Universitario 12 de Octubre, Avda. de Córdoba, s/n 28041, Madrid, Spain
| | - M Aramendi-Ramos
- Department of Clinical Analysis, Hospital Universitario 12 de Octubre, Madrid, Spain
| | - J L Eguiburu
- Department of Clinical Analysis, Hospital Universitario 12 de Octubre, Madrid, Spain
| | - A Pérez-Rivilla
- Department of Microbiology, Hospital Universitario 12 de Octubre, Madrid, Spain
| | - A Marchán-López
- Department of Internal Medicine, Hospital Universitario 12 de Octubre, Madrid, Spain
| | - M Rubio-Fernández
- Group of Neurodegenerative Diseases, Instituto de Investigación Hospital 12 de Octubre (i+12), Madrid, Spain.,Networked Biomedical Research Center in Neurodegenerative Diseases (CIBERNED), Madrid, Spain
| | - E Carro
- Group of Neurodegenerative Diseases, Instituto de Investigación Hospital 12 de Octubre (i+12), Madrid, Spain.,Networked Biomedical Research Center in Neurodegenerative Diseases (CIBERNED), Madrid, Spain
| | - J González de la Aleja
- Department of Neurology, Hospital Universitario 12 de Octubre, Avda. de Córdoba, s/n 28041, Madrid, Spain
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16
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Western Pacific ALS-PDC: Evidence implicating cycad genotoxins. J Neurol Sci 2020; 419:117185. [PMID: 33190068 DOI: 10.1016/j.jns.2020.117185] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2020] [Revised: 09/20/2020] [Accepted: 09/29/2020] [Indexed: 12/12/2022]
Abstract
Amyotrophic Lateral Sclerosis and Parkinsonism-Dementia Complex (ALS-PDC) is a disappearing neurodegenerative disorder of apparent environmental origin formerly hyperendemic among Chamorros of Guam-USA, Japanese residents of the Kii Peninsula, Honshu Island, Japan and Auyu-Jakai linguistic groups of Papua-Indonesia on the island of New Guinea. The most plausible etiology is exposure to genotoxins in seed of neurotoxic cycad plants formerly used for food and/or medicine. Primary suspicion falls on methylazoxymethanol (MAM), the aglycone of cycasin and on the non-protein amino acid β-N-methylamino-L-alanine, both of which are metabolized to formaldehyde. Human and animal studies suggest: (a) exposures occurred early in life and sometimes during late fetal brain development, (b) clinical expression of neurodegenerative disease appeared years or decades later, and (c) pathological changes in various tissues indicate the disease was not confined to the CNS. Experimental evidence points to toxic molecular mechanisms involving DNA damage, epigenetic changes, transcriptional mutagenesis, neuronal cell-cycle reactivation and perturbation of the ubiquitin-proteasome system that led to polyproteinopathy and culminated in neuronal degeneration. Lessons learned from research on ALS-PDC include: (a) familial disease may reflect common toxic exposures across generations, (b) primary disease prevention follows cessation of exposure to culpable environmental triggers; and (c) disease latency provides a prolonged period during which to intervene therapeutically. Exposure to genotoxic chemicals ("slow toxins") in the early stages of life should be considered in the search for the etiology of ALS-PDC-related neurodegenerative disorders, including sporadic forms of ALS, progressive supranuclear palsy and Alzheimer's disease.
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17
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Disruption of cellular proteostasis by H1N1 influenza A virus causes α-synuclein aggregation. Proc Natl Acad Sci U S A 2020; 117:6741-6751. [PMID: 32152117 DOI: 10.1073/pnas.1906466117] [Citation(s) in RCA: 83] [Impact Index Per Article: 20.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Neurodegenerative diseases feature specific misfolded or misassembled proteins associated with neurotoxicity. The precise mechanisms by which protein aggregates first arise in the majority of sporadic cases have remained unclear. Likely, a first critical mass of misfolded proteins starts a vicious cycle of a prion-like expansion. We hypothesize that viruses, having evolved to hijack the host cellular machinery for catalyzing their replication, lead to profound disturbances of cellular proteostasis, resulting in such a critical mass of protein aggregates. Here, we investigated the effect of influenza virus (H1N1) strains on proteostasis of proteins associated with neurodegenerative diseases in Lund human mesencephalic dopaminergic cells in vitro and infection of Rag knockout mice in vivo. We demonstrate that acute H1N1 infection leads to the formation of α-synuclein and Disrupted-in-Schizophrenia 1 (DISC1) aggregates, but not of tau or TDP-43 aggregates, indicating a selective effect on proteostasis. Oseltamivir phosphate, an antiinfluenza drug, prevented H1N1-induced α-synuclein aggregation. As a cell pathobiological mechanism, we identified H1N1-induced blocking of autophagosome formation and inhibition of autophagic flux. In addition, α-synuclein aggregates appeared in infected cell populations connected to the olfactory bulbs following intranasal instillation of H1N1 in Rag knockout mice. We propose that H1N1 virus replication in neuronal cells can induce seeds of aggregated α-synuclein or DISC1 that may be able to initiate further detrimental downstream events and should thus be considered a risk factor in the pathogenesis of synucleinopathies or a subset of mental disorders. More generally, aberrant proteostasis induced by viruses may be an underappreciated factor in initiating protein misfolding.
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18
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Riederer P, Berg D, Casadei N, Cheng F, Classen J, Dresel C, Jost W, Krüger R, Müller T, Reichmann H, Rieß O, Storch A, Strobel S, van Eimeren T, Völker HU, Winkler J, Winklhofer KF, Wüllner U, Zunke F, Monoranu CM. α-Synuclein in Parkinson's disease: causal or bystander? J Neural Transm (Vienna) 2019; 126:815-840. [PMID: 31240402 DOI: 10.1007/s00702-019-02025-9] [Citation(s) in RCA: 73] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Accepted: 05/29/2019] [Indexed: 12/13/2022]
Abstract
Parkinson's disease (PD) comprises a spectrum of disorders with differing subtypes, the vast majority of which share Lewy bodies (LB) as a characteristic pathological hallmark. The process(es) underlying LB generation and its causal trigger molecules are not yet fully understood. α-Synuclein (α-syn) is a major component of LB and SNCA gene missense mutations or duplications/triplications are causal for rare hereditary forms of PD. As typical sporadic PD is associated with LB pathology, a factor of major importance is the study of the α-syn protein and its pathology. α-Syn pathology is, however, also evident in multiple system atrophy (MSA) and Lewy body disease (LBD), making it non-specific for PD. In addition, there is an overlap of these α-synucleinopathies with other protein-misfolding diseases. It has been proven that α-syn, phosphorylated tau protein (pτ), amyloid beta (Aβ) and other proteins show synergistic effects in the underlying pathogenic mechanisms. Multiple cell death mechanisms can induce pathological protein-cascades, but this can also be a reverse process. This holds true for the early phases of the disease process and especially for the progression of PD. In conclusion, while rare SNCA gene mutations are causal for a minority of familial PD patients, in sporadic PD (where common SNCA polymorphisms are the most consistent genetic risk factor across populations worldwide, accounting for 95% of PD patients) α-syn pathology is an important feature. Conversely, with regard to the etiopathogenesis of α-synucleinopathies PD, MSA and LBD, α-syn is rather a bystander contributing to multiple neurodegenerative processes, which overlap in their composition and individual strength. Therapeutic developments aiming to impact on α-syn pathology should take this fact into consideration.
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Affiliation(s)
- Peter Riederer
- Clinic and Policlinic for Psychiatry, Psychosomatics and Psychotherapy, University Hospital Würzburg, University of Würzburg, Margarete-Höppel-Platz 1, 97080, Würzburg, Germany. .,Department of Psychiatry, University of South Denmark, Odense, Denmark.
| | - Daniela Berg
- Department of Neurology, UKHS, Christian-Albrechts-Universität, Campus Kiel, Kiel, Germany
| | - Nicolas Casadei
- NGS Competence Center Tübingen, Institute of Medical Genetics and Applied Genomics, University of Tübingen, Tübingen, Germany
| | - Fubo Cheng
- NGS Competence Center Tübingen, Institute of Medical Genetics and Applied Genomics, University of Tübingen, Tübingen, Germany
| | - Joseph Classen
- Department of Neurology, University Hospital Leipzig, Leipzig, Germany
| | - Christian Dresel
- Department of Neurology, Center for Movement Disorders, Neuroimaging Center Mainz, Clinical Neurophysiology, Forschungszentrum Translationale Neurowissenschaften (FTN), Rhein-Main-Neuronetz, Mainz, Germany
| | | | - Rejko Krüger
- Clinical and Experimental Neuroscience, LCSB (Luxembourg Centre for Systems, Biomedicine), University of Luxembourg, Esch-sur-Alzette and Centre Hospitalier de Luxembourg (CHL), Luxembourg, Luxembourg.,National Center for Excellence in Research, Parkinson's disease (NCER-PD), Parkinson Research Clinic, Centre Hospitalier de Luxembourg, Luxembourg, Luxembourg
| | - Thomas Müller
- Department of Neurology, Alexianer St. Joseph Berlin-Weißensee, Berlin, Germany
| | - Heinz Reichmann
- Department of Neurology, University of Dresden, Dresden, Germany
| | - Olaf Rieß
- Institute of Medical Genetics and Applied Genomics, Tübingen, Germany
| | - Alexander Storch
- Department of Neurology, University of Rostock, Rostock, Germany.,German Centre for Neurodegenerative Diseases (DZNE) Rostock/Greifswald, Rostock, Germany
| | - Sabrina Strobel
- Department of Neuropathology, Institute of Pathology, University of Würzburg, Würzburg, Germany
| | - Thilo van Eimeren
- Department of Neurology, University Hospital of Cologne, Cologne, Germany
| | | | - Jürgen Winkler
- Department Kopfkliniken, Molekulare Neurologie, Universitätsklinikum Erlangen, Erlangen, Germany
| | - Konstanze F Winklhofer
- Institute of Biochemistry and Pathobiochemistry, Ruhr-Universität Bochum, Bochum, Germany
| | - Ullrich Wüllner
- Department of Neurology, University of Bonn, German Center for Neurodegenerative Diseases (DZNE Bonn), Bonn, Germany
| | - Friederike Zunke
- Department of Biochemistry, Medical Faculty, University of Kiel, Kiel, Germany
| | - Camelia-Maria Monoranu
- Department of Neuropathology, Institute of Pathology, University of Würzburg, Würzburg, Germany
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19
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Yang L, Wang H, Liu L, Xie A. The Role of Insulin/IGF-1/PI3K/Akt/GSK3β Signaling in Parkinson's Disease Dementia. Front Neurosci 2018. [PMID: 29515352 PMCID: PMC5826217 DOI: 10.3389/fnins.2018.00073] [Citation(s) in RCA: 119] [Impact Index Per Article: 19.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Dementia, a condition that frequently afflicts patients in advanced stages of Parkinson's disease (PD), results in decreased quality of life and survival time. Nevertheless, the pathological mechanisms underlying Parkinson's disease dementia (PDD) are not completely understood. The symptoms characteristic of PDD may be the result of functional and structural deficiencies. The present study implicates the accumulation of Lewy bodies in the cortex and limbic system as a potent trigger in the development of PDD. In addition, significant Alzheimer-type pathologies, including amyloid-β (Aβ) plaques and NFTs, are observed in almost half of PDD patients. Interestingly, links between PDD pathogenesis and the mechanisms underlying the development of insulin resistance have begun to emerge. Furthermore, previous studies have demonstrated that insulin treatment reduces amyloid plaques in Alzheimer's disease (AD), and normalizes the production and functionality of dopamine and ameliorates motor impairments in 6-OHDA-induced rat PD models. GSK3β, a downstream substrate of PI3K/Akt signaling following induction by insulin and IGF-1, exerts an influence on AD and PD physiopathology. The genetic overexpression of GSK3β in cortex and hippocampus results in signs of neurodegeneration and spatial learning deficits in in vivo models (Lucas et al., 2001), whereas its inhibition results in improvements in cognitive impairment in these rodents, including AD and PD. Accordingly, insulin- or IGF-1-activated PI3K/Akt/GSK3β signaling may be involved in PDD pathogenesis, at least in the pathology of PD-type + AD-type.
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Affiliation(s)
- Liying Yang
- Department of Neurology, Affiliated Hospital of Qingdao University, Qingdao, China
| | - Hongyan Wang
- Department of Neurology, Qingdao Municipal Hospital, Qingdao, China
| | - Lijun Liu
- Department of Neurology, Affiliated Hospital of Qingdao University, Qingdao, China
| | - Anmu Xie
- Department of Neurology, Affiliated Hospital of Qingdao University, Qingdao, China
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20
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Mittal SO, Hassan A, Sanchez J, Robertson C. Powassan virus postencephalitic parkinsonism. Neurol Clin Pract 2018; 7:527-530. [PMID: 29431163 DOI: 10.1212/cpj.0000000000000391] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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21
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Guo T, Noble W, Hanger DP. Roles of tau protein in health and disease. Acta Neuropathol 2017; 133:665-704. [PMID: 28386764 PMCID: PMC5390006 DOI: 10.1007/s00401-017-1707-9] [Citation(s) in RCA: 565] [Impact Index Per Article: 80.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2017] [Revised: 03/26/2017] [Accepted: 03/26/2017] [Indexed: 01/18/2023]
Abstract
Tau is well established as a microtubule-associated protein in neurons. However, under pathological conditions, aberrant assembly of tau into insoluble aggregates is accompanied by synaptic dysfunction and neural cell death in a range of neurodegenerative disorders, collectively referred to as tauopathies. Recent advances in our understanding of the multiple functions and different locations of tau inside and outside neurons have revealed novel insights into its importance in a diverse range of molecular pathways including cell signalling, synaptic plasticity, and regulation of genomic stability. The present review describes the physiological and pathophysiological properties of tau and how these relate to its distribution and functions in neurons. We highlight the post-translational modifications of tau, which are pivotal in defining and modulating tau localisation and its roles in health and disease. We include discussion of other pathologically relevant changes in tau, including mutation and aggregation, and how these aspects impinge on the propensity of tau to propagate, and potentially drive neuronal loss, in diseased brain. Finally, we describe the cascade of pathological events that may be driven by tau dysfunction, including impaired axonal transport, alterations in synapse and mitochondrial function, activation of the unfolded protein response and defective protein degradation. It is important to fully understand the range of neuronal functions attributed to tau, since this will provide vital information on its involvement in the development and pathogenesis of disease. Such knowledge will enable determination of which critical molecular pathways should be targeted by potential therapeutic agents developed for the treatment of tauopathies.
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Affiliation(s)
- Tong Guo
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, SE5 9NU, UK
| | - Wendy Noble
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, SE5 9NU, UK
| | - Diane P Hanger
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, SE5 9NU, UK.
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22
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Schlossmacher MG, Tomlinson JJ, Santos G, Shutinoski B, Brown EG, Manuel D, Mestre T. Modelling idiopathic Parkinson disease as a complex illness can inform incidence rate in healthy adults: the P R EDIGT score. Eur J Neurosci 2017; 45:175-191. [PMID: 27859866 PMCID: PMC5324667 DOI: 10.1111/ejn.13476] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2016] [Revised: 10/16/2016] [Accepted: 11/07/2016] [Indexed: 12/15/2022]
Abstract
Fifty-five years after the concept of dopamine replacement therapy was introduced, Parkinson disease (PD) remains an incurable neurological disorder. To date, no disease-modifying therapeutic has been approved. The inability to predict PD incidence risk in healthy adults is seen as a limitation in drug development, because by the time of clinical diagnosis ≥ 60% of dopamine neurons have been lost. We have designed an incidence prediction model founded on the concept that the pathogenesis of PD is similar to that of many disorders observed in ageing humans, i.e. a complex, multifactorial disease. Our model considers five factors to determine cumulative incidence rates for PD in healthy adults: (i) DNA variants that alter susceptibility (D), e.g. carrying a LRRK2 or GBA risk allele; (ii) Exposure history to select environmental factors including xenobiotics (E); (iii) Gene-environment interactions that initiate pathological tissue responses (I), e.g. a rise in ROS levels, misprocessing of amyloidogenic proteins (foremost, α-synuclein) and dysregulated inflammation; (iv) sex (or gender; G); and importantly, (v) time (T) encompassing ageing-related changes, latency of illness and propagation of disease. We propose that cumulative incidence rates for PD (PR ) can be calculated in healthy adults, using the formula: PR (%) = (E + D + I) × G × T. Here, we demonstrate six case scenarios leading to young-onset parkinsonism (n = 3) and late-onset PD (n = 3). Further development and validation of this prediction model and its scoring system promise to improve subject recruitment in future intervention trials. Such efforts will be aimed at disease prevention through targeted selection of healthy individuals with a higher prediction score for developing PD in the future and at disease modification in subjects that already manifest prodromal signs.
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Affiliation(s)
- Michael G. Schlossmacher
- Neuroscience ProgramOttawa Hospital Research Institute451 Smyth RoadRGH #1414OttawaONK1H 8M5Canada
- Division of NeurologyDepartment of MedicineThe Ottawa HospitalOttawaCanada
- University of Ottawa Brain & Mind Research InstituteOttawaCanada
- Faculty of MedicineUniversity of OttawaOttawaCanada
| | - Julianna J. Tomlinson
- Neuroscience ProgramOttawa Hospital Research Institute451 Smyth RoadRGH #1414OttawaONK1H 8M5Canada
- University of Ottawa Brain & Mind Research InstituteOttawaCanada
| | | | - Bojan Shutinoski
- Neuroscience ProgramOttawa Hospital Research Institute451 Smyth RoadRGH #1414OttawaONK1H 8M5Canada
- University of Ottawa Brain & Mind Research InstituteOttawaCanada
| | - Earl G. Brown
- Neuroscience ProgramOttawa Hospital Research Institute451 Smyth RoadRGH #1414OttawaONK1H 8M5Canada
- Faculty of MedicineUniversity of OttawaOttawaCanada
- Department of Biochemistry, Microbiology and ImmunologyUniversity of OttawaOttawaCanada
| | - Douglas Manuel
- Faculty of MedicineUniversity of OttawaOttawaCanada
- Clinical Epidemiology ProgramOttawa Hospital Research InstituteOttawaCanada
| | - Tiago Mestre
- Neuroscience ProgramOttawa Hospital Research Institute451 Smyth RoadRGH #1414OttawaONK1H 8M5Canada
- Division of NeurologyDepartment of MedicineThe Ottawa HospitalOttawaCanada
- University of Ottawa Brain & Mind Research InstituteOttawaCanada
- Faculty of MedicineUniversity of OttawaOttawaCanada
- Clinical Epidemiology ProgramOttawa Hospital Research InstituteOttawaCanada
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Arendt T, Stieler JT, Holzer M. Tau and tauopathies. Brain Res Bull 2016; 126:238-292. [DOI: 10.1016/j.brainresbull.2016.08.018] [Citation(s) in RCA: 333] [Impact Index Per Article: 41.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2016] [Revised: 08/31/2016] [Accepted: 08/31/2016] [Indexed: 12/11/2022]
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Kovacs GG. Invited review: Neuropathology of tauopathies: principles and practice. Neuropathol Appl Neurobiol 2015; 41:3-23. [PMID: 25495175 DOI: 10.1111/nan.12208] [Citation(s) in RCA: 350] [Impact Index Per Article: 38.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2014] [Accepted: 12/09/2014] [Indexed: 12/11/2022]
Abstract
Tauopathies are clinically, morphologically and biochemically heterogeneous neurodegenerative diseases characterized by the deposition of abnormal tau protein in the brain. The neuropathological phenotypes are distinguished based on the involvement of different anatomical areas, cell types and presence of distinct isoforms of tau in the pathological deposits. The nomenclature of primary tauopathies overlaps with the modern classification of frontotemporal lobar degeneration. Neuropathological phenotypes comprise Pick's disease, progressive supranuclear palsy, corticobasal degeneration, argyrophilic grain disease, primary age-related tauopathy, formerly called also as neurofibrillary tangle-only dementia, and a recently characterized entity called globular glial tauopathy. Mutations in the gene encoding the microtubule-associated protein tau are associated with frontotemporal dementia and parkinsonism linked to chromosome 17. In addition, further neurodegenerative conditions with diverse aetiologies may be associated with tau pathologies. Thus, the spectrum of tau pathologies and tauopathy entities expands beyond the traditionally discussed disease forms. Detailed multidisciplinary studies are still required to understand their significance.
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Affiliation(s)
- G G Kovacs
- Institute of Neurology, Medical University of Vienna, Vienna, Austria
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Alpha-synuclein and tau: teammates in neurodegeneration? Mol Neurodegener 2014; 9:43. [PMID: 25352339 PMCID: PMC4230508 DOI: 10.1186/1750-1326-9-43] [Citation(s) in RCA: 184] [Impact Index Per Article: 18.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2014] [Accepted: 10/16/2014] [Indexed: 11/25/2022] Open
Abstract
The accumulation of α-synuclein aggregates is the hallmark of Parkinson’s disease, and more generally of synucleinopathies. The accumulation of tau aggregates however is classically found in the brains of patients with dementia, and this type of neuropathological feature specifically defines the tauopathies. Nevertheless, in numerous cases α-synuclein positive inclusions are also described in tauopathies and vice versa, suggesting a co-existence or crosstalk of these proteinopathies. Interestingly, α-synuclein and tau share striking common characteristics suggesting that they may work in concord. Tau and α-synuclein are both partially unfolded proteins that can form toxic oligomers and abnormal intracellular aggregates under pathological conditions. Furthermore, mutations in either are responsible for severe dominant familial neurodegeneration. Moreover, tau and α-synuclein appear to promote the fibrillization and solubility of each other in vitro and in vivo. This suggests that interactions between tau and α-synuclein form a deleterious feed-forward loop essential for the development and spreading of neurodegeneration. Here, we review the recent literature with respect to elucidating the possible links between α-synuclein and tau.
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Marreiros R, Müller-Schiffmann A, Bader V, Selvarajah S, Dey D, Lingappa VR, Korth C. Viral capsid assembly as a model for protein aggregation diseases: Active processes catalyzed by cellular assembly machines comprising novel drug targets. Virus Res 2014; 207:155-64. [PMID: 25451064 DOI: 10.1016/j.virusres.2014.10.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2014] [Revised: 09/09/2014] [Accepted: 10/01/2014] [Indexed: 11/18/2022]
Abstract
Viruses can be conceptualized as self-replicating multiprotein assemblies, containing coding nucleic acids. Viruses have evolved to exploit host cellular components including enzymes to ensure their replicative life cycle. New findings indicate that also viral capsid proteins recruit host factors to accelerate their assembly. These assembly machines are RNA-containing multiprotein complexes whose composition is governed by allosteric sites. In the event of viral infection, the assembly machines are recruited to support the virus over the host and are modified to achieve that goal. Stress granules and processing bodies may represent collections of such assembly machines, readily visible by microscopy but biochemically labile and difficult to isolate by fractionation. We hypothesize that the assembly of protein multimers such as encountered in neurodegenerative or other protein conformational diseases, is also catalyzed by assembly machines. In the case of viral infection, the assembly machines have been modified by the virus to meet the virus' need for rapid capsid assembly rather than host homeostasis. In the case of the neurodegenerative diseases, it is the monomers and/or low n oligomers of the so-called aggregated proteins that are substrates of assembly machines. Examples for substrates are amyloid β peptide (Aβ) and tau in Alzheimer's disease, α-synuclein in Parkinson's disease, prions in the prion diseases, Disrupted-in-schizophrenia 1 (DISC1) in subsets of chronic mental illnesses, and others. A likely continuum between virus capsid assembly and cell-to-cell transmissibility of aggregated proteins is remarkable. Protein aggregation diseases may represent dysfunction and dysregulation of these assembly machines analogous to the aberrations induced by viral infection in which cellular homeostasis is pathologically reprogrammed. In this view, as for viral infection, reset of assembly machines to normal homeostasis should be the goal of protein aggregation therapeutics. A key basis for the commonality between viral and neurodegenerative disease aggregation is a broader definition of assembly as more than just simple aggregation, particularly suited for the crowded cytoplasm. The assembly machines are collections of proteins that catalytically accelerate an assembly reaction that would occur spontaneously but too slowly to be relevant in vivo. Being an enzyme complex with a functional allosteric site, appropriated for a non-physiological purpose (e.g. viral infection or conformational disease), these assembly machines present a superior pharmacological target because inhibition of their active site will amplify an effect on their substrate reaction. Here, we present this hypothesis based on recent proof-of-principle studies against Aβ assembly relevant in Alzheimer's disease.
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Affiliation(s)
- Rita Marreiros
- Department Neuropathology, Heinrich Heine University Düsseldorf Medical School, Moorenstrasse 5, 40225 Düsseldorf, Germany
| | - Andreas Müller-Schiffmann
- Department Neuropathology, Heinrich Heine University Düsseldorf Medical School, Moorenstrasse 5, 40225 Düsseldorf, Germany
| | - Verian Bader
- Department Neuropathology, Heinrich Heine University Düsseldorf Medical School, Moorenstrasse 5, 40225 Düsseldorf, Germany
| | | | | | | | - Carsten Korth
- Department Neuropathology, Heinrich Heine University Düsseldorf Medical School, Moorenstrasse 5, 40225 Düsseldorf, Germany.
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Abstract
Parkinson's disease is one of the most frequent progressive degenerative disorders with unknown origin of the nervous system. The commutation of the disease on Guam led to the discovery of a neurotoxin which was also found in other continents. This neurotoxin was identified in the common cyanobacteria (blue-green algae). Early clinical observations suggested some loose correlations with gastric and duodenal ulcer and Parkinson's disease, while recent studies revealed a toxin, almost identical to that found in cyanobacteria in one strain of Helicobacter pylori, which proved to cause Parkinson like symptoms in animals. Therefore, it cannot be ruled out that there is a slowly progressive poisoning in Parkinson's disease. The disease specific alpha-sinuclein inclusions can be found in nerve cells of the intestinal mucosa far before the appearance of clinical symptoms indicating that the disease may start in the intestines. These results are strengthened by the results of Borody's fecal transplants, after which in Parkinson patients showed a symptomatic improvement. Based on these observations the Parkinson puzzle is getting complete. Although these observations are not evidence based, they may indicate a new way for basic clinical research, as well as a new way of thinking for clinicians. These new observations in psycho-neuro-immunology strengthen the fact that immunological factors may also play a critical factor facilitating local cell necrosis which may be influenced easily.
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Affiliation(s)
- András Guseo
- Fejér Megyei Szent György Kórház Idegosztály Székesfehérvár Cserkész u.
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Dunning CJ, Reyes JF, Steiner JA, Brundin P. Can Parkinson's disease pathology be propagated from one neuron to another? Prog Neurobiol 2012; 97:205-19. [DOI: 10.1016/j.pneurobio.2011.11.003] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2011] [Revised: 11/02/2011] [Accepted: 11/08/2011] [Indexed: 12/12/2022]
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Protein coding of neurodegenerative dementias: the neuropathological basis of biomarker diagnostics. Acta Neuropathol 2010; 119:389-408. [PMID: 20198481 DOI: 10.1007/s00401-010-0658-1] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2009] [Revised: 02/12/2010] [Accepted: 02/13/2010] [Indexed: 12/11/2022]
Abstract
Neuropathological diagnosis of neurodegenerative dementias evolved by adapting the results of neuroanatomy, biochemistry, and cellular and molecular biology. Milestone findings of intra- and extracellular argyrophilic structures, visualizing protein deposition, initiated a protein-based classification. Widespread application of immunohistochemical and biochemical investigations revealed that (1) there are modifications of proteins intrinsic to disease (species that are phosphorylated, nitrated, oligomers, proteinase-resistant, with or without amyloid characteristics; cleavage products), (2) disease forms characterized by the accumulation of a single protein only are rather the exception than the rule, and (3) some modifications of proteins elude present neuropathological diagnostic procedures. In this review, we summarize how neuropathology, together with biochemistry, contributes to disease typing, by demonstrating a spectrum of disorders characterized by the deposition of various modifications of various proteins in various locations. Neuropathology may help to elucidate how brain pathologies alter the detectability of proteins in body fluids by upregulation of physiological forms or entrapment of different proteins. Modifications of at least the five most relevant proteins (amyloid-beta, prion protein, tau, alpha-synuclein, and TDP-43), aided by analysis of further "attracted" proteins, are pivotal to be evaluated simultaneously with different methods. This should complement the detection of biomarkers associated with pathogenetic processes, and also neuroimaging and genetic analysis, in order to obtain a highly personalized diagnostic profile. Defining clusters of patients based on the patterns of protein deposition and immunohistochemically or biochemically detectable modifications of proteins ("codes") may have higher prognostic predictive value, may be useful for monitoring therapy, and may open new avenues for research on pathogenesis.
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