alpha-synuclein and Multiple-System-Atrophy

Multiple system atrophy (MSA) is a rare neurodegenerative disorder with unclear etiology, currently difficult and delayed diagnosis, and rapid progression, leading to disability and lethality within 6 to 9 years after symptom onset. The neuropathology of MSA classifies the disease in the group of a-synucleinopathies together with Parkinson's disease and other Lewy body disorders, but features specific oligodendroglial inclusions, which are pathognomonic for MSA. MSA has no efficient therapy to date. Development of experimental models is crucial to elucidate the disease mechanisms in progression and to provide a tool for preclinical screening of putative therapies for MSA. In vitro and in vivo models, based on selective neurotoxicity, a-synuclein oligodendroglial overexpression, and strain-specific propagation of a-synuclein fibrils, have been developed, reflecting various facets of MSA pathology. Over the years, the continuous exchange from bench to bedside and backward has been crucial for the advancing of MSA modelling, elucidating MSA pathogenic pathways, and understanding the existing translational gap to successful clinical trials in MSA. The review discusses specifically advantages and limitations of the PLP-a-syn mouse model of MSA, which recapitulates motor and non-motor features of the human disease with underlying striatonigral degeneration, degeneration of autonomic centers, and sensitized olivopontocerebellar system, strikingly mirroring human MSA pathology.

Topics: alpha-Synuclein; Animals; Brain; Disease Models, Animal; Humans; Mice; Mice, Transgenic; Multiple System Atrophy; Neuropathology; Oligodendroglia; Phenotype; Translational Research, Biomedical

Alpha-synucleinopathies, such as Parkinson's disease, dementia with Lewy bodies and multiple system atrophy, are characterized by aberrant accumulation of alpha-synuclein and synaptic dysfunction leading to motor and cognitive deficits. Animal models of alpha-synucleinopathy have greatly facilitated the mechanistic understanding of the disease and the development of therapeutics. Various transgenic, alpha-synuclein fibril-injected, and toxin-injected animal models of Parkinson's disease and multiple system atrophy that recapitulate the disease pathology have been developed and widely used. Recent advances in positron emission tomography have allowed the noninvasive visualization of molecular alterations, underpinning behavioral dysfunctions in the brains of animal models and the longitudinal monitoring of treatment effects. Imaging studies in these disease animal models have employed multi-tracer PET designs to reveal dopaminergic deficits together with other molecular alterations. This review focuses on the development of new positron emission tomography tracers and studies of alpha-synuclein, synaptic vesicle glycoprotein 2A neurotransmitter receptor deficits such as dopaminergic receptor, dopaminergic transporter, serotonergic receptor, vesicular monoamine transporter 2, hypometabolism, neuroinflammation, mitochondrial dysfunction and leucine rich repeat kinase 2 in animal models of Parkinson's disease. The outstanding challenges and emerging applications are outlined, such as investigating the gut-brain-axis by using positron emission tomography in animal models, and provide a future outlook.

Topics: alpha-Synuclein; Animals; Disease Models, Animal; Multiple System Atrophy; Parkinson Disease; Positron-Emission Tomography

Synucleinopathies, including Parkinson's disease (PD), dementia with Lewy Bodies (DLB), and multiple system atrophy (MSA), are characterized by the misfolding and subsequent aggregation of alpha-synuclein (α-syn) that accumulates in cytoplasmic inclusions bodies in the cells of affected brain regions. Since the seminal report of likely-aggregated α-syn presence within the Lewy bodies by Spillantini et al. in 1997, the keyword "synuclein aggregation" has appeared in over 6000 papers (Source: PubMed October 2022). Studying, observing, describing, and quantifying α-syn aggregation is therefore of paramount importance, whether it happens in tubo, in vitro, in post-mortem samples, or in vivo. The past few years have witnessed tremendous progress in understanding aggregation mechanisms and identifying various polymorphs. In this context of growing complexity, it is of utmost importance to understand what tools we possess, what exact information they provide, and in what context they may be applied. Nonetheless, it is also crucial to rationalize the relevance of the information and the limitations of these methods for gauging the final result. In this review, we present the main techniques that have shaped the current views about α-syn structure and dynamics, with particular emphasis on the recent breakthroughs that may change our understanding of synucleinopathies.

Topics: alpha-Synuclein; Humans; Lewy Bodies; Multiple System Atrophy; Parkinson Disease; Synucleinopathies

The synucleinopathies, which include Parkinson's disease, dementia with Lewy bodies, and multiple system atrophy, are a class of human neurodegenerative disorders unified by the presence of α-synuclein aggregates in the brain. Considerable clinical and pathological heterogeneity exists within and among the individual synucleinopathies. A potential explanation for this variability is the existence of distinct conformational strains of α-synuclein aggregates that cause different disease manifestations. Like prion strains, α-synuclein strains can be delineated based on their structural architecture, with structural differences among α-synuclein aggregates leading to unique biochemical attributes and neuropathological properties in humans and animal models. Bolstered by recent high-resolution structural data from patient brain-derived material, it has now been firmly established that there are conformational differences among α-synuclein aggregates from different human synucleinopathies. Moreover, recombinant α-synuclein can be polymerized into several structurally distinct aggregates that exhibit unique pathological properties. In this review, we outline the evidence supporting the existence of α-synuclein strains and highlight how they can act as drivers of phenotypic heterogeneity in the human synucleinopathies.

Topics: alpha-Synuclein; Animals; Brain; Humans; Multiple System Atrophy; Parkinson Disease; Protein Conformation; Synucleinopathies

Dysfunction of the serotonergic system represents an important feature in synucleinopathies like Parkinson disease (PD), dementia with Lewy bodies (DLB) and Multiple system atrophy (MSA). Serotonergic fibers from the raphe nuclei (RN) extend broadly throughout the central nervous system, innervating several brain areas affected in synucleinopathies. Alterations of the serotonergic system are associated with non-motor symptoms or motor complications in PD as well as with autonomic features of MSA. Postmortem studies, data from transgenic animal models and imaging techniques greatly contributed to the understanding of this serotonergic pathophysiology in the past, even leading to preclinical and clinical candidate drug tests targeting different parts of the serotonergic system. In this article, we review most recent work extending the knowledge of the serotonergic system and highlighting its relevance for the pathophysiology of synucleinopathies.

Topics: alpha-Synuclein; Humans; Lewy Body Disease; Multiple System Atrophy; Parkinson Disease; Serotonin; Synucleinopathies

Multiple system atrophy (MSA) is a debilitating movement disorder with unknown etiology. Patients present characteristic parkinsonism and/or cerebellar dysfunction in the clinical phase, resulting from progressive deterioration in the nigrostriatal and olivopontocerebellar regions. MSA patients have a prodromal phase subsequent to the insidious onset of neuropathology. Therefore, understanding the early pathological events is important in determining the pathogenesis, which will assist with developing disease-modifying therapy. Although the definite diagnosis of MSA relies on the positive post-mortem finding of oligodendroglial inclusions composed of α-synuclein, only recently has MSA been verified as an oligodendrogliopathy with secondary neuronal degeneration. We review up-to-date knowledge of human oligodendrocyte lineage cells and their association with α-synuclein, and discuss the postulated mechanisms of how oligodendrogliopathy develops, oligodendrocyte progenitor cells as the potential origins of the toxic seeds of α-synuclein, and the possible networks through which oligodendrogliopathy induces neuronal loss. Our insights will shed new light on the research directions for future MSA studies.

Topics: alpha-Synuclein; Cell Lineage; Humans; Multiple System Atrophy; Neurons; Parkinsonian Disorders

α-Synucleinopathies, such as Parkinson's disease (PD), dementia with Lewy bodies (DLB) and multiple system atrophy, are a class of neurodegenerative diseases exhibiting intracellular inclusions of misfolded α-synuclein (αSyn), referred to as Lewy bodies or oligodendroglial cytoplasmic inclusions (Papp-Lantos bodies). Even though the specific cellular distribution of aggregated αSyn differs in PD and DLB patients, both groups show a significant pathological overlap, raising the discussion of whether PD and DLB are the same or different diseases. Besides clinical investigation, we will focus in addition on methodologies, such as protein seeding assays (real-time quaking-induced conversion), to discriminate between different types of α-synucleinopathies. This approach relies on the seeding conversion properties of misfolded αSyn, supporting the hypothesis that different conformers of misfolded αSyn may occur in different types of α-synucleinopathies. Understanding the pathological processes influencing the disease progression and phenotype, provoked by different αSyn conformers, will be important for a personalized medical treatment in future.

Topics: alpha-Synuclein; Humans; Lewy Bodies; Multiple System Atrophy; Parkinson Disease; Synucleinopathies

Parkinson's disease (PD), dementia with Lewy bodies (DLB), and multiple system atrophy (MSA) are termed synucleinopathies, disorders that are characterized by the intracellular aggregation of the protein ɑ-synuclein. The cellular tropism of synuclein pathology in these syndromes is notably distinct since in the Lewy disorders, PD and DLB, ɑSyn forms aggregates in neurons whereas in MSA ɑSyn forms aggregates in oligodendrocytes. Studies examining ɑSyn pathology in experimental models and in human brain have now identified fibrillar ɑSyn with unique but distinct molecular signatures, suggesting that the structure of these ɑSyn fibrils might be closely tied to their cellular ontogeny. In contrast to the native structural heterogeneity of ɑSyn in vitro, the conformational landscape of fibrillar ɑSyn in human brain and in vivo transmission models appears to be remarkably uniform. Here, we review the studies by which we propose a hypothesis that the cellular host environment might be in part responsible for how ɑSyn filaments assemble into phenotype-specific strains. We postulate that the maturation of ɑSyn strains develops as a function of their in vivo transmission routes and cell-specific risk factors. The impact of the cellular environment on the structural diversity of ɑSyn might have important implications for the design of preclinical studies and their use for the development of ɑSyn-based biomarkers and therapeutic strategies. By combining phenotype-specific fibrils and relevant synucleinopathy transmission models, preclinical models might more closely reflect unique disease phenotypes.

Topics: alpha-Synuclein; Humans; Multiple System Atrophy; Neurons; Parkinson Disease; Synucleinopathies

Multiple system atrophy (MSA) is a rare oligodendroglial α-synucleinopathy characterized by neurodegeneration in striatonigral and olivopontocerebellar regions and autonomic brain centres. It causes complex cumulative motor and non-motor disability with fast progression and effective therapy is currently lacking. The difficulties in the diagnosis and treatment of MSA are largely related to the incomplete understanding of the pathogenesis of the disease. The MSA pathogenic landscape is complex, and converging findings from genetic and neuropathological studies as well as studies in experimental models of MSA have indicated the involvement of genetic and epigenetic changes; α-synuclein misfolding, aggregation and spreading; and α-synuclein strain specificity. These studies also indicate the involvement of myelin and iron dyshomeostasis, neuroinflammation, mitochondrial dysfunction and other cell-specific aspects that are relevant to the fast progression of MSA. In this Review, we discuss these findings and emphasize the implications of the complexity of the multifactorial pathogenic cascade for future translational research and its impact on biomarker discovery and treatment target definitions.

Topics: alpha-Synuclein; Brain; Humans; Multiple System Atrophy; Myelin Sheath; Oligodendroglia

Parkinsonian disorders, such as Parkinson's disease (PD), multiple system atrophy (MSA), dementia with Lewy bodies (DLB), progressive supranuclear palsy (PSP) and corticobasal syndrome (CBS), share early motor symptoms but have distinct pathophysiology. As a result, accurate premortem diagnosis is challenging for neurologists, hindering efforts for disease-modifying therapeutic discovery. Extracellular vesicles (EVs) contain cell-state-specific biomolecules and can cross the blood-brain barrier to the peripheral circulation, providing a unique central nervous system (CNS) insight. This meta-analysis evaluated blood-isolated neuronal and oligodendroglial EVs (nEVs and oEVs) α-synuclein levels in Parkinsonian disorders.. Following PRISMA guidelines, the meta-analysis included 13 studies. An inverse-variance random-effects model quantified effect size (SMD), QUADAS-2 assessed risk of bias and publication bias was evaluated. Demographic and clinical variables were collected for meta-regression.. The meta-analysis included 1,565 patients with PD, 206 with MSA, 21 with DLB, 172 with PSP, 152 with CBS and 967 healthy controls (HCs). Findings suggest that combined concentrations of nEVs and oEVs α-syn is higher in patients with PD compared to HCs (SMD = 0.21, p = 0.021), while nEVs α-syn is lower in patients with PSP and CBS compared to patients with PD (SMD = -1.04, p = 0.0017) or HCs (SMD = -0.41, p < 0.001). Additionally, α-syn in nEVs and/or oEVs did not significantly differ in patients with PD vs. MSA, contradicting the literature. Meta-regressions show that demographic and clinical factors were not significant predictors of nEVs or oEVs α-syn concentrations.. The results highlight the need for standardized procedures and independent validations in biomarker studies and the development of improved biomarkers for distinguishing Parkinsonian disorders.

Topics: alpha-Synuclein; Biomarkers; Central Nervous System; Extracellular Vesicles; Humans; Multiple System Atrophy; Parkinson Disease; Parkinsonian Disorders

Synucleinopathies are a group of neurodegenerative disorders, classically characterized by the accumulation of aggregated alpha synuclein (aSyn) in the central nervous system. Parkinson's disease (PD) and multiple system atrophy (MSA) are the two prominent members of this family. Current treatment options mainly focus on the motor symptoms of these diseases. However, non-motor symptoms, including gastrointestinal (GI) symptoms, have recently gained particular attention, as they are frequently associated with synucleinopathies and often arise before motor symptoms. The gut-origin hypothesis has been proposed based on evidence of an ascending spreading pattern of aggregated aSyn from the gut to the brain, as well as the comorbidity of inflammatory bowel disease and synucleinopathies. Recent advances have shed light on the mechanisms underlying the progression of synucleinopathies along the gut-brain axis. Given the rapidly expanding pace of research in the field, this review presents a summary of the latest findings on the gut-to-brain spreading of pathology and potential pathology-reinforcing mediators in synucleinopathies. Here, we focus on 1) gut-to-brain communication pathways, including neuronal pathways and blood circulation, and 2) potential molecular signalling mediators, including bacterial amyloid proteins, microbiota dysbiosis-induced alterations in gut metabolites, as well as host-derived effectors, including gut-derived peptides and hormones. We highlight the clinical relevance and implications of these molecular mediators and their possible mechanisms in synucleinopathies. Moreover, we discuss their potential as diagnostic markers in distinguishing the subtypes of synucleinopathies and other neurodegenerative diseases, as well as for developing novel individualized therapeutic options for synucleinopathies.

Topics: alpha-Synuclein; Brain; Humans; Multiple System Atrophy; Neurons; Parkinson Disease; Synucleinopathies

Like many neurodegenerative diseases, Parkinson's disease (PD) is characterized by the formation of proteinaceous aggregates in brain cells. In PD, those proteinaceous aggregates are formed by the α-synuclein (αSyn) and are considered the trademark of this neurodegenerative disease. In addition to PD, αSyn pathological aggregation is also detected in atypical Parkinsonism, including Dementia with Lewy Bodies (DLB), Multiple System Atrophy (MSA), as well as neurodegeneration with brain iron accumulation, some cases of traumatic brain injuries, and variants of Alzheimer's disease. Collectively, these (and other) disorders are referred to as synucleinopathies, highlighting the relation between disease type and protein misfolding/aggregation. Despite these pathological relationships, however, synucleinopathies cover a wide range of pathologies, present with a multiplicity of symptoms, and arise from dysfunctions in different neuroanatomical regions and cell populations. Strikingly, αSyn deposition occurs in different types of cells, with oligodendrocytes being mainly affected in MSA, while aggregates are found in neurons in PD. If multiple factors contribute to the development of a pathology, especially in the cases of slow-developing neurodegenerative disorders, the common presence of αSyn aggregation, as both a marker and potential driver of disease, is puzzling. In this review, we will focus on comparing PD, DLB, and MSA, from symptomatology to molecular description, highlighting the role and contribution of αSyn aggregates in each disorder. We will particularly present recent evidence for the involvement of conformational strains of αSyn aggregates and discuss the reciprocal relationship between αSyn strains and the cellular milieu. Moreover, we will highlight the need for effective methodologies for the strainotyping of aggregates to ameliorate diagnosing capabilities and therapeutic treatments.

Topics: alpha-Synuclein; Humans; Lewy Body Disease; Multiple System Atrophy; Parkinson Disease; Protein Aggregates; Synucleinopathies

Alpha-synuclein seed amplification assays (α-syn SAAs) are promising diagnostic methods for Parkinson's disease (PD) and other synucleinopathies. However, there is limited consensus regarding the diagnostic and differential diagnostic performance of α-syn SAAs on biofluids and peripheral tissues.. A comprehensive research was performed in PubMed, Web of Science, Embase and Cochrane Library. Meta-analysis was performed using a random-effects model. A network meta-analysis based on an ANOVA model was conducted to compare the relative accuracy of α-syn SAAs with different specimens.. The pooled sensitivity and specificity of α-syn SAAs in distinguishing PD from healthy controls or non-neurodegenerative neurological controls were 0.91 (95% confidence interval [CI] 0.89-0.92) and 0.95 (95% CI 0.94-0.96) for cerebrospinal fluid (CSF); 0.91 (95% CI 0.86-0.94) and 0.92 (95% CI 0.87-0.95) for skin; 0.80 (95% CI 0.66-0.89) and 0.87 (95% CI 0.69-0.96) for submandibular gland; 0.44 (95% CI 0.30-0.59) and 0.92 (95% CI 0.79-0.98) for gastrointestinal tract; 0.79 (95% CI 0.70-0.86) and 0.88 (95% CI 0.77-0.95) for saliva; and 0.51 (95% CI 0.39-0.62) and 0.91 (95% CI 0.84-0.96) for olfactory mucosa (OM). The pooled sensitivity and specificity were 0.91 (95% CI 0.89-0.93) and 0.50 (95% CI 0.44-0.55) for CSF, 0.92 (95% CI 0.83-0.97) and 0.22 (95% CI 0.06-0.48) for skin, and 0.55 (95% CI 0.42-0.68) and 0.50 (95% CI 0.35-0.65) for OM in distinguishing PD from multiple system atrophy. The pooled sensitivity and specificity were 0.92 (95% CI 0.89-0.94) and 0.84 (95% CI 0.73-0.91) for CSF, 0.92 (95% CI 0.83-0.97) and 0.88 (95% CI 0.64-0.99) for skin and 0.63 (95% CI 0.52-0.73) and 0.86 (95% CI 0.64-0.97) for OM in distinguishing PD from progressive supranuclear palsy. The pooled sensitivity and specificity were 0.94 (95% CI 0.90-0.97) and 0.95 (95% CI 0.77-1.00) for CSF and 0.94 (95% CI 0.84-0.99) and 0.86 (95% CI 0.42-1.00) for skin in distinguishing PD from corticobasal degeneration.. α-Synuclein SAAs of CSF, skin, saliva, submandibular gland, gastrointestinal tract and OM are promising diagnostic assays for PD, with CSF and skin α-syn SAAs demonstrating higher diagnostic performance.

Topics: alpha-Synuclein; Biomarkers; Humans; Multiple System Atrophy; Network Meta-Analysis; Parkinson Disease

Alpha-synucleinopathies (α-synucleinopathies) such as Parkinson's disease (PD), Parkinson's disease dementia (PDD), dementia with Lewy bodies (DLB), and multiple system atrophy (MSA) are all characterized by aggregates of alpha-synuclein (α-syn), but display heterogeneous clinical and pathological phenotypes. The mechanism underlying this heterogeneity is thought to be due to diversity in the α-syn strains present across the diseases. α-syn obtained from the post-mortem brain of patients who lived with these conditions is heterogenous, and displays a different protease sensitivity, ultrastructure, cytotoxicity, and seeding potential. The primary aim of this review is to summarize previous studies investigating these concepts, which not only reflect the idea of different syn strains being present, but demonstrate that each property explains a small part of a much larger puzzle. Strains of α-syn appear at the center of the correlation between α-syn properties and the disease phenotype, likely influenced by external factors. There are considerable similarities in the properties of disease-specific α-syn strains, but MSA seems to consistently display more aggressive traits. Elucidating the molecular underpinnings of heterogeneity amongst α-synucleinopathies holds promise for future clinical translation, allowing for the development of personalized medicine approaches tackling the root cause of each α-synucleinopathy.

Topics: alpha-Synuclein; Dementia; Humans; Multiple System Atrophy; Parkinson Disease; Synucleinopathies

The α-synucleinopathies comprise a group of adult-onset neurodegenerative disorders including Parkinson's disease (PD), multiple system atrophy (MSA), dementia with Lewy bodies (DLB,) and - as a restricted non-motor form - pure autonomic failure (PAF). Neuropathologically, the α-synucleinopathies are characterized by aggregates of misfolded α-synuclein in the central and peripheral nervous system. Cardiovascular autonomic failure is a common non-motor symptom in people with PD, a key diagnostic criterion in MSA, a supportive feature for the diagnosis of DLB and disease-defining in PAF. The site of autonomic nervous system lesion differs between the α-synucleinopathies, with a predominantly central lesion pattern in MSA versus a peripheral one in PD, DLB, and PAF. In clinical practice, overlapping autonomic features often challenge the differential diagnosis among the α-synucleinopathies, but also distinguish them from related disorders, such as the tauopathies or other neurodegenerative ataxias. In this review, we discuss the differential diagnostic yield of cardiovascular autonomic failure in individuals presenting with isolated autonomic failure, parkinsonism, cognitive impairment, or cerebellar ataxia.

Topics: alpha-Synuclein; Diagnosis, Differential; Humans; Lewy Body Disease; Multiple System Atrophy; Parkinson Disease; Pure Autonomic Failure; Synucleinopathies

α-synucleinopathies, encompassing Parkinson's disease, dementia with Lewy bodies, and multiple system atrophy, are devastating neurodegenerative diseases for which available therapeutic options are scarce, mostly because of our limited understanding of their pathophysiology. Although these pathologies are attributed to an intracellular accumulation of the α-synuclein protein in the nervous system with subsequent neuronal loss, the trigger(s) of this accumulation is/are not clearly identified. Among the existing hypotheses, interest in the hypothesis advocating the involvement of infectious agents in the onset of these diseases is renewed. In this article, we aimed to review the ongoing relevant factors favoring and opposing this hypothesis, focusing on (1) the potential antimicrobial role of α-synuclein, (2) potential entry points of pathogens in regard to early symptoms of diverse α-synucleinopathies, (3) pre-existing literature reviews assessing potential associations between infectious agents and Parkinson's disease, (4) original studies assessing these associations for dementia with Lewy bodies and multiple system atrophy (identified through a systematic literature review), and finally (5) potential susceptibility factors modulating the effects of infectious agents on the nervous system. © 2022 International Parkinson and Movement Disorder Society.

Topics: alpha-Synuclein; Humans; Lewy Body Disease; Multiple System Atrophy; Parkinson Disease; Synucleinopathies

Alpha-synuclein (α-syn) has been suggested to have many functions including, vesicle transport in neurons, transcriptional regulator, modulator of immune cell maturation and response, and a role as an antimicrobial peptide. This protein forms insoluble aggregates, called Lewy bodies, in several neurodegenerative diseases, termed synucleinopathies, including Parkinson's disease (PD), Multiple System Atrophy, and Lewy Body Dementia, and aggregates are also commonly found in Alzheimer's disease. Moreover, multiplications and point mutations in the gene cause rare autosomal dominant forms of parkinsonism, which resemble sporadic PD. It has been suggested that the accumulation of α-syn in the monomeric state followed by aggregation of the protein and seeding of further pathogenic α-syn aggregates are key steps in the pathogenesis of synucleinopathies. The triggers of α-syn aggregation in neurodegeneration are unknown, but inflammation caused by bacterial and viral pathogens or exposure to environmental toxins have been implicated. The purpose of this review is to present emerging evidence that α-syn may play a role in the immune response to pathogens. We present recent findings suggesting that upregulation of α-syn levels is a normal response to infections. We propose that under certain conditions (e.g., dysregulated inflammatory responses due to genetic predisposition and aging), monomeric α-syn will form oligomers that are taken up by nerve endings and undergo axonal transport to the central nervous system, where they can aggregate into pathogenic fibrils. Under unfavorable conditions, we suggest that this process can trigger neurodegenerative disease. Therefore, a deeper understanding of the roles of α-syn in the immune system could provide crucial insights into the origins of synucleinopathies.

Topics: alpha-Synuclein; Humans; Lewy Bodies; Multiple System Atrophy; Parkinson Disease; Up-Regulation

The abnormal accumulation of α-synuclein in the brain is a common feature of Parkinson's disease (PD), PD dementia (PDD), dementia with Lewy bodies (DLB) and multiple system atrophy (MSA), and synucleinopathies that present with overlapping but distinct clinical symptoms that include motor and cognitive deficits. Synapse degeneration is the crucial neuropathological event in these synucleinopathies and the neuropathological correlate of connectome dysfunction. The cognitive and motor deficits resulting from the connectome dysfunction are currently measured by scalar systems that are limited in their sensitivity and largely subjective. Ideally, a marker of synapse degeneration would correlate with measures of cognitive or motor impairment, and could therefore be used as a more objective, surrogate biomarker of the core clinical features of these diseases. Furthermore, an objective surrogate biomarker that can detect and monitor the progression of synapse degeneration would improve patient management and clinical trial design, and could provide a measure of therapeutic response. Here, we review the published findings relating to candidate biomarkers of synapse degeneration in PD, PDD, DLB, and MSA patient-derived biofluids and discuss the findings in the context of the mechanisms associated with α-synuclein-mediated synapse degeneration. Understanding these mechanisms is essential not only for discovery of biomarkers, but also to improve our understanding of the earliest changes in disease pathogenesis of synucleinopathies.

Topics: alpha-Synuclein; Biomarkers; Humans; Lewy Body Disease; Multiple System Atrophy; Synapses; Synucleinopathies

Multiple system atrophy is a rapidly progressive and fatal neurodegenerative disorder. While numerous preclinical studies suggested efficacy of potentially disease modifying agents, none of those were proven to be effective in large-scale clinical trials. Three major strategies are currently pursued in preclinical and clinical studies attempting to slow down disease progression. These target α-synuclein, neuroinflammation, and restoration of neurotrophic support. This review provides a comprehensive overview on ongoing preclinical and clinical developments of disease modifying therapies. Furthermore, we will focus on potential shortcomings of previous studies that can be avoided to improve data quality in future studies of this rare disease.

Topics: alpha-Synuclein; Humans; Multiple System Atrophy; Parkinson Disease

α-Synuclein (αS) is remarkable for both its extensive conformational plasticity and pathologic prion-like properties. Physiologically, αS may populate disordered monomeric, helically folded tetrameric, or membrane-bound oligomeric states. Pathologically, αS may assemble into toxic oligomers and subsequently fibrils, the prion-like transmission of which is implicated in a class of neurodegenerative disorders collectively termed α-synucleinopathies. Notably, αS does not adopt a single "amyloid fold", but rather exists as structurally distinct amyloid-like conformations referred to as "strains". The inoculation of animal models with different strains induces distinct pathologies, and emerging evidence suggests that the propagation of disease-specific strains underlies the differential pathologies observed in patients with different α-synucleinopathies. The characterization of αS strains has provided insight into the structural basis for the overlapping, yet distinct, symptoms of Parkinson's disease, multiple system atrophy, and dementia with Lewy bodies. In this review, we first explore the physiological and pathological differences between conformational states of αS. We then discuss recent studies on the influence of micro-environmental factors on αS species formation, propagation, and the resultant pathological characteristics. Lastly, we review how an understanding of αS conformational properties has been translated to emerging strain amplification technologies, which have provided further insight into the role of specific strains in distinct α-synucleinopathies, and show promise for the early diagnosis of disease.

Topics: alpha-Synuclein; Animals; Multiple System Atrophy; Parkinson Disease; Prions; Synucleinopathies

The clinical differentiation between multiple system atrophy (MSA), Parkinson's disease (PD), dementia with Lewy bodies (DLB), as well as the distinction between these synucleinopathies from other neurodegenerative disorders can be challenging, particularly at early disease stages or when the presentation is atypical. That is also true for predicting the fate of patients with limited or prodromal forms of synucleinopathies such as pure autonomic failure (PAF) or idiopathic REM-sleep behavior disorder (iRBD) which are known to be at risk of developing MSA, PD, or DLB. After discussing current classification concepts of the synucleinopathies, this invited mini-review reflects on two recently described and validated spinal fluid biomarkers, namely neurofilament light chain (NfL) and α-synuclein oligomers detected by protein aggregation assays, that have shown great promise not only as markers differentiating MSA from the Lewy-body synucleinopathies but also as markers that predict future phenoconversion to MSA among patients with PAF. Discussed are the strengths and limitations of these markers, and how they appear to complement each other nicely as a biomarker panel, enhancing the specificity of one of these markers, yet adding further robustness and simplicity to a marker that is technically rather challenging. The review concludes with thoughts on potential next steps in the development of fluid biomarkers in this rapidly emerging field.

Topics: alpha-Synuclein; Biomarkers; Humans; Lewy Body Disease; Multiple System Atrophy; Parkinson Disease; Pure Autonomic Failure; REM Sleep Behavior Disorder; Synucleinopathies

Parkinson disease (PD) is the second most common neurodegenerative disease, and the most common synucleinopathy, as alpha-synuclein (α-syn), a prion-like protein, plays an important pathophysiologic role in its onset and progression. Although neuropathologic changes begin many years before the onset of motor manifestations, diagnosis still relies on the identification of the motor symptoms, which hinders to formulate an early diagnosis. Because α-syn misfolding and aggregation precede clinical manifestations, the possibility to identify these phenomena in patients with PD would allow us to recognize the disease at the earliest, premotor phases, as a consequence of the transition from a clinical to a molecular diagnosis. Seed amplification assays (SAAs) are a group of techniques that currently support the diagnosis of prion subacute encephalopathies, namely Creutzfeldt-Jakob disease. These techniques enable the detection of minimal amounts of prions in CSF and other matrices of affected patients. Recently, SAAs have been successfully applied to detect misfolded alpha-synuclein (α-syn) in CSF, olfactory mucosa, submandibular gland biopsies, skin, and saliva of patients with Parkinson disease (PD) and other synucleinopathies. In these categories, they can differentiate PD and dementia with Lewy bodies (DLBs) from control subjects, even in the prodromal stages of the disease. In differential diagnosis, SAAs satisfactorily differentiated PD, DLB, and multiple system atrophy (MSA) from nonsynucleinopathy parkinsonisms. The kinetic analysis of the SAA fluorescence profiles allowed the identification of synucleinopathy-dependent α-syn fibrils conformations, commonly referred to as strains, which have demonstrated diagnostic potential in differentiating among synucleinopathies, especially between Lewy body diseases (LBDs) (PD and DLB) and MSA. In front of these highly promising data, which make the α-syn seeding activity detected by SAAs as the most promising diagnostic biomarker for synucleinopathies, there are still preanalytical and analytical issues, mostly related to the assay standardization, which need to be solved. In this review, we discuss the key findings supporting the clinical application of α-syn SAAs to identify PD and other synucleinopathies, the unmet needs, and future perspectives.

Topics: alpha-Synuclein; Humans; Kinetics; Lewy Body Disease; Multiple System Atrophy; Parkinson Disease; Prions; Synucleinopathies

Amyotrophic lateral sclerosis (ALS) is the most common adult-onset motor neuron disease classified as both a neurodegenerative and neuromuscular disorder. With a complex aetiology and no current cure for ALS, broadening the understanding of disease pathology and therapeutic avenues is required to progress with patient care. Alpha-synuclein (αSyn) is a hallmark for disease in neurodegenerative disorders, such as Parkinson's disease, Lewy body dementia, and multiple system atrophy. A growing body of evidence now suggests that αSyn may also play a pathological role in ALS, with αSyn-positive Lewy bodies co-aggregating alongside known ALS pathogenic proteins, such as

Topics: alpha-Synuclein; Amyotrophic Lateral Sclerosis; Humans; Lewy Bodies; Lewy Body Disease; Multiple System Atrophy; Synucleinopathies

The therapeutic strategies currently available for neurodegenerative diseases such as Parkinson's disease target only the symptoms of the disease. Parkinson's disease, dementia with Lewy bodies, and multiple system atrophy can be summarized as synucleinopathies, as they are all characterized by the aggregation and accumulation of alpha-synuclein (α-syn) in the brain. Targeting α-syn by its formation and progression opens a new and promising disease-modifying therapeutic strategy. Thus, several distinct immunotherapeutic approaches are currently being evaluated in clinical trials. The objective of this article is to review, from a biological perspective, the most important properties of these passive and active immunotherapies to point out their relevance and suitability for the treatment of synucleinopathies.

Topics: alpha-Synuclein; Humans; Multiple System Atrophy; Parkinson Disease; Synucleinopathies; Vaccination

Alpha-synuclein(αSyn) aggregates are definite pathological hallmarks of α-synucleinopathies. Seeding amplification assays (SAAs) have been developed to detect trace amounts of αSyn oligomers in vivo.. Herein, we assessed the diagnostic accuracy of the αSyn-SAAs across biospecimens, diagnostic references, methods, and subtypes.. A systematic literature search yielded 36 eligible studies for a meta-analysis of the sensitivity and specificity of αSyn-SAAs in patients with α-synucleinopathies(n = 2722) and controls(n = 2278). Pooled sensitivities and specificities with 95% confidence intervals (CIs) were calculated using bivariate random-effects models and a meta-regression analysis was performed.. The summary sensitivity and specificity of αSyn-SAAs positivity for the diagnosis of α-synucleinopathies were 0.88(95% CIs = 0.84-0.91) and 0.95(0.93-0.97), respectively. Two covariates (biospecimen and diagnostic reference) were significant in fitting the meta-regression model (likelihood-ratio test for sensitivity and specificity, p < 0.01, p = 0.01, respectively). Skin αSyn-SAAs exhibited the highest sensitivity 0.92(0.87-0.95), which was not different from that of cerebrospinal fluid (CSF)(0.90(0.86-0.93), p = 0.39). Olfactory mucosa αSyn-SAAs exhibited a lower sensitivity 0.64(0.49-0.76) than those of the other two specimens(p = 0.02, 0.01, compared to CSF and skin, respectively). Application of pathological diagnostic standards were associated with a higher specificity of αSyn-SAAs compared to clinical diagnosis (p < 0.01). The diagnostic sensitivity and specificity of CSF αSyn-SAAs were 0.91(0.87-0.94) and 0.96(0.93-0.98) for Lewy body disease, 0.90(0.79-0.95) and 0.96(0.90-0.98) for prodromal α-synucleinopathies, and 0.63(0.24-0.90) and 0.97(0.93-0.99) for multiple system atrophy.. αSyn-SAAs are promising in vivo detectors of abnormal αSyn aggregates and may aid the early diagnosis of α-synucleinopathies.

Topics: alpha-Synuclein; Humans; Lewy Body Disease; Multiple System Atrophy; Sensitivity and Specificity; Synucleinopathies

The aberrant accumulation of α-Synuclein within oligodendrocytes is an enigmatic, pathological feature specific to Multiple system atrophy (MSA). Since the characterization of the disease in 1969, decades of research have focused on unravelling the pathogenic processes that lead to the formation of oligodendroglial cytoplasmic inclusions. The discovery of aggregated α-Synuclein (α-Syn) being the primary constituent of glial cytoplasmic inclusions has spurred several lines of research investigating the relationship between the pathogenic accumulation of the protein and oligodendrocytes. Recent developments have identified the ability of α-Syn to form conformationally distinct "strains" with varying behavioral characteristics and toxicities. Such "strains" are potentially disease-specific, providing insight into the enigmatic nature of MSA. This review discusses the evidence for MSA-specific α-Syn strains, highlighting the current methods for detecting and characterizing MSA patient-derived α-Syn. Given the differing behaviors of α-Syn strains, we explore the seeding and spreading capabilities of MSA-specific strains, postulating their influence on the aggressive nature of the disease. These ideas culminate into one key question: What causes MSA-specific strain formation? To answer this, we discuss the interplay between oligodendrocytes, neurons and α-Syn, exploring the ability of each cell type to contribute to the aggregate formation while postulating the effect of additional variables such as protein interactions, host characteristics and environmental factors. Thus, we propose the idea that MSA strain formation results from the intricate interrelation between neurons and oligodendrocytes, with deficits in each cell type required to initiate α-Syn aggregation and MSA pathogenesis.

Topics: alpha-Synuclein; Brain; Humans; Multiple System Atrophy; Neurons; Oligodendroglia

Multiple system atrophy (MSA) is a rare neurodegenerative disease characterized by parkinsonism, cerebellar impairment, and autonomic failure. Although the causes of MSA onset and progression remain uncertain, its pathogenesis may involve oxidative stress via the generation of excess reactive oxygen species and/or destruction of the antioxidant system. One of the most powerful antioxidants is glutathione, which plays essential roles as an antioxidant enzyme cofactor, cysteine-storage molecule, major redox buffer, and neuromodulator, in addition to being a key antioxidant in the central nervous system. Glutathione levels are known to be reduced in neurodegenerative diseases. In addition, genes regulating redox states have been shown to be post-transcriptionally modified by microRNA (miRNA), one of the most important types of non-coding RNA. miRNAs have been reported to be dysregulated in several diseases, including MSA. In this review, we focused on the relation between glutathione deficiency, miRNA dysregulation and oxidative stress and their close relation with MSA pathology.

Topics: alpha-Synuclein; Antioxidants; Cerebellum; Glutathione; Humans; MicroRNAs; Multiple System Atrophy; Parkinsonian Disorders

Multiple system atrophy (MSA) is a rapidly progressive, fatal neurodegenerative disease of uncertain aetiology that belongs to the family of α-synucleinopathies. It clinically presents with parkinsonism, cerebellar, autonomic, and motor impairment in variable combinations. Pathological hallmarks are fibrillary α-synuclein (αSyn)-rich glial cytoplasmic inclusions (GCIs) mainly involving oligodendroglia and to a lesser extent neurons, inducing a multisystem neurodegeneration, glial activation, and widespread demyelinization. The neuronal αSyn pathology of MSA has molecular properties different from Lewy bodies in Parkinson's disease (PD), both of which could serve as a pool of αSyn (prion) seeds that could initiate and drive the pathogenesis of synucleinopathies. The molecular cascade leading to the "prion-like" transfer of "strains" of aggregated αSyn contributing to the progression of the disease is poorly understood, while some presented evidence that MSA is a prion disease. However, this hypothesis is difficult to reconcile with postmortem analysis of human brains and the fact that MSA-like pathology was induced by intracerebral inoculation of human MSA brain homogenates only in homozygous mutant 53T mice, without production of disease-specific GCIs, or with replication of MSA prions in primary astrocyte cultures from transgenic mice expressing human αSyn. Whereas recent intrastriatal injection of Lewy body-derived or synthetic human αSyn fibrils induced PD-like pathology including neuronal αSyn aggregates in macaques, no such transmission of αSyn pathology in non-human primates by MSA brain lysate has been reported until now. Given the similarities between αSyn and prions, there is a considerable debate whether they should be referred to as "prions", "prion-like", "prionoids", or something else. Here, the findings supporting the proposed nature of αSyn as a prion and its self-propagation through seeding as well as the transmissibility of neurodegenerative disorders are discussed. The proof of disease causation rests on the concordance of scientific evidence, none of which has provided convincing evidence for the classification of MSA as a prion disease or its human transmission until now.

Topics: alpha-Synuclein; Animals; Astrocytes; Brain; Humans; Inclusion Bodies; Lewy Bodies; Macaca; Mice; Mice, Transgenic; Models, Theoretical; Multiple System Atrophy; Neurodegenerative Diseases; Neuroglia; Neurons; Parkinson Disease; Parkinsonian Disorders; Prions; Protein Folding

Multiple system atrophy (MSA) is a progressive neurodegenerative disorder characterized by striatonigral degeneration (SND), olivopontocerebellar atrophy (OPCA), and dysautonomia with cerebellar ataxia or parkinsonian motor features. Isolated autonomic dysfunction with predominant genitourinary dysfunction and orthostatic hypotension and REM sleep behavior disorder are common characteristics of a prodromal phase, which may occur years prior to motor-symptom onset. MSA is a unique synucleinopathy, in which alpha-synuclein (aSyn) accumulates and forms insoluble inclusions in the cytoplasm of oligodendrocytes, termed glial cytoplasmic inclusions (GCIs). The origin of, and precise mechanism by which aSyn accumulates in MSA are unknown, and, therefore, disease-modifying therapies to halt or slow the progression of MSA are currently unavailable. For these reasons, much focus in the field is concerned with deciphering the complex neuropathological mechanisms by which MSA begins and progresses through the course of the disease. This review focuses on the history, etiopathogenesis, neuropathology, as well as cell and animal models of MSA.

Topics: alpha-Synuclein; Animals; Inclusion Bodies; Models, Animal; Multiple System Atrophy; Nerve Degeneration

Abnormal accumulation of aggregated α-synuclein (α-Syn) is seen in a variety of neurodegenerative diseases, including Parkinson's disease (PD), multiple system atrophy (MSA), dementia with Lewy body (DLB), Parkinson's disease dementia (PDD), and even subsets of Alzheimer's disease (AD) showing Lewy-body-like pathology. These synucleinopathies exhibit differences in their clinical and pathological representations, reminiscent of prion disorders. Emerging evidence suggests that α-Syn self-assembles and polymerizes into conformationally diverse polymorphs in vitro and in vivo, similar to prions. These α-Syn polymorphs arising from the same precursor protein may exhibit strain-specific biochemical properties and the ability to induce distinct pathological phenotypes upon their inoculation in animal models. In this review, we discuss clinical and pathological variability in synucleinopathies and several aspects of α-Syn fibril polymorphism, including the existence of high-resolution molecular structures and brain-derived strains. The current review sheds light on the recent advances in delineating the structure-pathogenic relationship of α-Syn and how diverse α-Syn molecular polymorphs contribute to the existing clinical heterogeneity in synucleinopathies.

Topics: alpha-Synuclein; Alzheimer Disease; Amyloid; Brain; Humans; Lewy Bodies; Multiple System Atrophy; Parkinson Disease; Prion Diseases; Protein Aggregates

Synucleinopathies are clinically and pathologically heterogeneous disorders characterized by pathologic aggregates of α-synuclein in neurons and glia, in the form of Lewy bodies, Lewy neurites, neuronal cytoplasmic inclusions, and glial cytoplasmic inclusions. Synucleinopathies can be divided into two major disease entities: Lewy body disease and multiple system atrophy (MSA). Common clinical presentations of Lewy body disease are Parkinson's disease (PD), PD with dementia, and dementia with Lewy bodies (DLB), while MSA has two major clinical subtypes, MSA with predominant cerebellar ataxia and MSA with predominant parkinsonism. There are currently no disease-modifying therapies for the synucleinopathies, but information obtained from molecular genetics and models that explore mechanisms of α-synuclein conversion to pathologic oligomers and insoluble fibrils offer hope for eventual therapies. It remains unclear how α-synuclein can be associated with distinct cellular pathologies (e.g., Lewy bodies and glial cytoplasmic inclusions) and what factors determine neuroanatomical and cell type vulnerability. Accumulating evidence from in vitro and in vivo experiments suggests that α-synuclein species derived from Lewy body disease and MSA are distinct "strains" having different seeding properties. Recent advancements in in vitro seeding assays, such as real-time quaking-induced conversion (RT-QuIC) and protein misfolding cyclic amplification (PMCA), not only demonstrate distinct seeding activity in the synucleinopathies, but also offer exciting opportunities for molecular diagnosis using readily accessible peripheral tissue samples. Cryogenic electron microscopy (cryo-EM) structural studies of α-synuclein derived from recombinant or brain-derived filaments provide new insight into mechanisms of seeding in synucleinopathies. In this review, we describe clinical, genetic and neuropathologic features of synucleinopathies, including a discussion of the evolution of classification and staging of Lewy body disease. We also provide a brief discussion on proposed mechanisms of Lewy body formation, as well as evidence supporting the existence of distinct α-synuclein strains in Lewy body disease and MSA.

Topics: alpha-Synuclein; Humans; Lewy Bodies; Lewy Body Disease; Multiple System Atrophy; Parkinson Disease; Synucleinopathies

Multiple system atrophy (MSA) is an adult onset, fatal neurodegenerative disease. However, no reliable biomarker is currently available to guide clinical diagnosis and help to determine the prognosis. Thus, a comprehensive meta-analysis is warranted to determine effective biomarkers for MSA and provide useful guidance for clinical diagnosis.. A comprehensive literature search was made of the PubMed, Embase, Cochrane and Web of Science databases for relevant clinical trial articles for 1984-2019. Two review authors examined the full-text records, respectively, and determined which studies met the inclusion criteria. We estimated the mean difference, standard deviation and 95% confidence intervals.. A total of 28 studies and 11 biomarkers were included in our analysis. Several biomarkers were found to be useful to distinguish MSA patients from healthy controls, including the reduction of phosphorylated tau, α-synuclein (α-syn), 42-amino-acid form of Aβ and total tau (t-tau), the elevation of neurofilament light-chain protein (NFL) in cerebrospinal fluid, the elevation of uric acid and reduction of homocysteine and coenzyme Q10 in plasma. Importantly, α-syn, NFL and t-tau could be used to distinguish MSA from Parkinson's disease (PD), indicating that these three biomarkers could be useful biomarkers in MSA diagnosis.. The findings of our meta-analysis demonstrated diagnostic biomarkers for MSA. Moreover, three biomarkers could be used in differential diagnosis of MSA and PD. The results could be helpful for the early diagnosis of MSA and the accuracy of MSA diagnosis.

Topics: alpha-Synuclein; Biomarkers; Diagnosis, Differential; Humans; Multiple System Atrophy; Parkinson Disease

Neuroinflammation has long been associated with central nervous system pathology in α-synucleinopathy disorders including Parkinson's disease and multiple system atrophy. In the past decade, research-focused efforts in preclinical and experimental models have rallied around this idea, and considerable effort has been made to delineate critical neuroinflammatory processes. In this article, we discuss challenges in preclinical research, notably the use of animal models to recapitulate and dissect disease phenotypes as well as the need for more sensitive, reliable radiotracers to detect on-target efficacy of immunomodulatory treatments in both human Parkinson's disease as well as preclinical models. © 2020 International Parkinson and Movement Disorder Society.

Topics: alpha-Synuclein; Animals; Disease Models, Animal; Humans; Inflammation; Models, Theoretical; Multiple System Atrophy; Synucleinopathies

Synucleinopathies are a group of neurodegenerative diseases characterized by the accumulation of α-synuclein aggregates in neurons, nerve fibers or glial cells. Three main types of diseases belong to the synucleinopathies: Parkinson's disease, dementia with Lewy bodies, and multiple system atrophy. All of them develop as a result of an interplay of genetic and environmental factors. Emerging evidence suggests that epigenetic mechanisms play an essential role in the development of synucleinopathies. Since there is no disease-modifying treatment for these disorders at this time, interest is growing in plant-derived chemicals as a potential treatment option. Phytochemicals are substances of plant origin that possess biological activity, which might have effects on human health. Phytochemicals with neuroprotective activity target different elements in pathogenic pathways due to their antioxidants, anti-inflammatory, and antiapoptotic properties, and ability to reduce cellular stress. Multiple recent studies demonstrate that the beneficial effects of phytochemicals may be explained by their ability to modulate the expression of genes implicated in synucleinopathies and other diseases. These substances may regulate transcription directly via transcription factors (TFs) or play the role of epigenetic regulators through their effect on histone modification, DNA methylation, and RNA-based mechanisms. Here, we summarize new data about the impact of phytochemicals on the pathogenesis of synucleinopathies through regulation of gene expression.

Topics: alpha-Synuclein; Brain; Epigenesis, Genetic; Gene Expression; Gene Expression Regulation; Humans; Lewy Bodies; Lewy Body Disease; Multiple System Atrophy; Neuroglia; Neurons; Parkinson Disease; Phytochemicals; Synucleinopathies

Multiple System Atrophy (MSA) is a rare, fatal neurodegenerative disorder. Its etiology and exact pathogenesis still remain poorly understood and currently no disease-modifying therapy is available to halt or slow down this detrimental neurodegenerative process. Hallmarks of the disease are α-synuclein rich glial cytoplasmic inclusions (GCIs). Neuropathologically, various degrees of striatonigral degeneration (SND) and olivopontocerebellar atrophy (OPCA) can be observed. Since the original descriptions of this multifaceted disorder, several steps forward have been made to clarify its neuropathological hallmarks and key pathophysiological mechanisms. The Austrian neuropathologist Kurt Jellinger substantially contributed to the understanding of the underlying neuropathology of this disease, to its standardized assessment and to a broad systematical clinic-pathological correlation. On the occasion of his 90th birthday, we reviewed the current state of the art in the field of MSA neuropathology, highlighting Prof. Jellinger's substantial contribution.

Topics: alpha-Synuclein; Austria; Humans; Inclusion Bodies; Multiple System Atrophy; Neuropathology

Multiple system atrophy (MSA) is a challenging neurodegenerative disorder with a difficult and often inaccurate early diagnosis, still lacking effective treatment. It is characterized by a highly variable clinical presentation with parkinsonism, cerebellar ataxia, autonomic dysfunction, and pyramidal signs, with a rapid progression and an aggressive clinical course. The definite MSA diagnosis is only possible post-mortem, when the presence of distinctive oligodendroglial cytoplasmic inclusions (GCIs), mainly composed of misfolded and aggregated α-Synuclein (α-Syn) is demonstrated. The process of α-Syn accumulation and aggregation within oligodendrocytes is accepted one of the main pathological events underlying MSA. However, MSA is considered a multifactorial disorder with multiple pathogenic events acting together including neuroinflammation, oxidative stress, and disrupted neurotrophic support, among others. The discussed here treatment approaches are based on our current understanding of the pathogenesis of MSA and the results of preclinical and clinical therapeutic studies conducted over the last 2 decades. We summarize leading disease-modifying approaches for MSA including targeting α-Syn pathology, modulation of neuroinflammation, and enhancement of neuroprotection. In conclusion, we outline some challenges related to the need to overcome the gap in translation between preclinical and clinical studies towards a successful disease modification in MSA.

Topics: alpha-Synuclein; Humans; Inclusion Bodies; Multiple System Atrophy; Oligodendroglia

Synucleinopathies are neurodegenerative diseases characterized by the accumulation of either neuronal/axonal or glial insoluble proteinaceous aggregates mainly composed of α-synuclein (α-syn). Among them, the most common disorders are Parkinson's disease, dementia with Lewy bodies, multiple system atrophy, and some forms of familial parkinsonism. Both α-syn fibrils and oligomers have been found to exert toxic effects on neurons or oligodendroglial cells, can activate neuroinflammatory responses, and mediate the spreading of α-syn pathology. This poses the question of which is the most toxic α-syn species. What is worst, α-syn appears as a very peculiar protein, exerting multiple physiological functions in neurons, especially at synapses, but without acquiring a stable tertiary structure. Its conformation is particularly plastic, and the protein can exist in a natively unfolded state (mainly in solution), partially α-helical folded state (when it interacts with biological membranes), or oligomeric state (tetramers or dimers with debated functional profile). The extent of α-syn expression impinges on the resilience of neuronal cells, as multiplications of its gene locus, or overexpression, can cause neurodegeneration and onset of motor phenotype. For these reasons, one of the main challenges in the field of synucleinopathies, which still nowadays can only be managed by symptomatic therapies, has been the development of strategies aimed at reducing α-syn levels, oligomer formation, fibrillation, or cell-to-cell transmission. This review resumes the therapeutic approaches that have been proposed or are under development to counteract α-syn pathology by direct targeting of this protein and discuss their pros and cons in relation to the current state-of-the-art α-syn biology.

Topics: alpha-Synuclein; Animals; Genetic Therapy; Humans; Immunotherapy; Intermediate Filament Proteins; Molecular Targeted Therapy; Multiple System Atrophy; Parkinson Disease; Synapses

Multiple system atrophy (MSA) is a debilitating and fatal neurodegenerative disorder. The disease severity warrants urgent development of disease-modifying therapy, but the disease pathogenesis is still enigmatic. Neurodegeneration in MSA brains is preceded by the emergence of glial cytoplasmic inclusions (GCIs), which are insoluble α-synuclein accumulations within oligodendrocytes (OLGs). Thus, preventive strategies against GCI formation may suppress disease progression. However, although numerous studies have tried to elucidate the molecular pathogenesis of GCI formation, difficulty remains in understanding the pathological interaction between the two pivotal aspects of GCIs; α-synuclein and OLGs. The difficulty originates from several enigmas: 1) what triggers the initial generation and possible propagation of pathogenic α-synuclein species? 2) what contributes to OLG-specific accumulation of α-synuclein, which is abundantly expressed in neurons but not in OLGs? and 3) how are OLGs and other glial cells affected and contribute to neurodegeneration? The primary pathogenesis of GCIs may involve myelin dysfunction and dyshomeostasis of the oligodendroglial cellular environment such as autophagy and iron metabolism. We have previously reported that oligodendrocyte precursor cells are more prone to develop intracellular inclusions in the presence of extracellular fibrillary α-synuclein. This finding implies a possibility that the propagation of GCI pathology in MSA brains is mediated through the internalization of pathological α-synuclein into oligodendrocyte precursor cells. In this review, in order to discuss the pathogenesis of GCIs, we will focus on the composition of neuronal and oligodendroglial inclusions in synucleinopathies. Furthermore, we will introduce some hypotheses on how α-synuclein pathology spreads among OLGs in MSA brains, in the light of our data from the experiments with primary oligodendrocyte lineage cell culture. While various reports have focused on the mysterious source of α-synuclein in GCIs, insights into the mechanism which regulates the uptake of pathological α-synuclein into oligodendroglial cells may yield the development of the disease-modifying therapy for MSA. The interaction between glial cells and α-synuclein is also highlighted with previous studies of post-mortem human brains, cultured cells, and animal models, which provide comprehensive insight into GCIs and the MSA pathomechanisms.

Topics: alpha-Synuclein; Humans; Inclusion Bodies; Lewy Bodies; Multiple System Atrophy; Neuroglia

Multiple system atrophy (MSA) is a rare, severe, and rapidly progressive neurodegenerative disorder categorized as an atypical parkinsonian syndrome. With a mean life expectancy of 6-9 years after diagnosis, MSA is clinically characterized by parkinsonism, cerebellar ataxia, autonomic failure, and poor l-Dopa responsiveness. Aside from limited symptomatic treatment, there is currently no disease-modifying therapy available. Consequently, distinct pharmacological targets have been explored and investigated in clinical studies based on MSA-related symptoms and pathomechanisms. Parkinsonism, cerebellar ataxia, and autonomic failure are the most important symptoms targeted by symptomatic treatments in current clinical trials. The most prominent pathological hallmark is oligodendroglial cytoplasmic inclusions containing alpha-synuclein, thus classifying MSA as synucleinopathy. Additionally, myelin and neuronal loss accompanied by micro- and astrogliosis are further distinctive features of MSA-related neuropathology present in numerous brain regions. Besides summarizing current symptomatic treatment strategies in MSA, this review critically reflects upon potential cellular targets and disease-modifying approaches for MSA such as (I) targeting α-syn pathology, (II) intervening neuroinflammation, and (III) neuronal loss. Although these single compound trials are aiming to interfere with distinct pathogenetic steps in MSA, a combined approach may be necessary to slow down the rapid progression of the oligodendroglial associated synucleinopathy.

Topics: Adrenergic alpha-1 Receptor Agonists; alpha-Synuclein; Animals; Disease Models, Animal; Humans; Induced Pluripotent Stem Cells; Monoamine Oxidase Inhibitors; Multiple System Atrophy; Neuroglia; Peroxidase

Mosaicism, the presence of genomic differences between cells due to post-zygotic somatic mutations, is widespread in the human body, including within the brain. A role for this in neurodegenerative diseases has long been hypothesised, and technical developments are now allowing the question to be addressed in detail. The rapidly accumulating evidence is discussed in this review, with a focus on recent developments. Somatic mutations of numerous types may occur, including single nucleotide variants (SNVs), copy number variants (CNVs), and retrotransposon insertions. They could act as initiators or risk factors, especially if they arise in development, although they could also result from the disease process, potentially contributing to progression. In common sporadic neurodegenerative disorders, relevant mutations have been reported in synucleinopathies, comprising somatic gains of SNCA in Parkinson's disease and multiple system atrophy, and in Alzheimer's disease, where a novel recombination mechanism leading to somatic variants of APP, as well as an excess of somatic SNVs affecting tau phosphorylation, have been reported. In Mendelian repeat expansion disorders, mosaicism due to somatic instability, first detected 25 years ago, has come to the forefront. Brain somatic SNVs occur in DNA repair disorders, and there is evidence for a role of several ALS genes in DNA repair. While numerous challenges, and need for further validation, remain, this new, or perhaps rediscovered, area of research has the potential to transform our understanding of neurodegeneration.

Topics: alpha-Synuclein; Alzheimer Disease; Amyloid beta-Protein Precursor; Amyotrophic Lateral Sclerosis; DNA Copy Number Variations; DNA Repair-Deficiency Disorders; DNA Repeat Expansion; Humans; Huntington Disease; Mosaicism; Multiple System Atrophy; Mutagenesis, Insertional; Mutation; Neurodegenerative Diseases; Parkinson Disease; Phosphorylation; Polymorphism, Single Nucleotide; Retroelements; Synucleinopathies; tau Proteins

Multiple system atrophy (MSA) is a progressive neurodegenerative disease variably associated with motor, nonmotor, and autonomic symptoms, resulting from putaminal and cerebellar degeneration and associated with glial cytoplasmic inclusions enriched with α-synuclein in oligodendrocytes and neurons. Although symptomatic treatment of MSA can provide significant improvements in quality of life, the benefit is often partial, limited by adverse effects, and fails to treat the underlying cause. Consistent with the multisystem nature of the disease and evidence that motor symptoms, autonomic failure, and depression drive patient assessments of quality of life, treatment is best achieved through a coordinated multidisciplinary approach driven by the patient's priorities and goals of care. Research into disease-modifying therapies is ongoing with a particular focus on synuclein-targeted therapies among others. This review focuses on both current management and emerging therapies for this devastating disease.

Topics: alpha-Synuclein; Animals; Anti-Inflammatory Agents; Disease Management; Genetic Therapy; Humans; Multiple System Atrophy; Neurons; Oligodendroglia; Quality of Life

α-Synuclein amyloid aggregation is a defining molecular feature of Parkinson's disease, Lewy body dementia, and multiple system atrophy, but can also be found in other neurodegenerative disorders such as Alzheimer's disease. The process of α-synuclein aggregation can be initiated through alternative nucleation mechanisms and dominated by different secondary processes giving rise to multiple amyloid polymorphs and intermediate species. Some aggregated species have more inherent abilities to induce cellular stress and toxicity, while others seem to be more potent in propagating neurodegeneration. The preference for particular types of polymorphs depends on the solution conditions and the cellular microenvironment that the protein encounters, which is likely related to the distinct cellular locations of α-synuclein inclusions in different synucleinopathies, and the existence of disease-specific amyloid polymorphs. In this review, we discuss our current understanding on the nature and structure of the various types of α-synuclein aggregated species and their possible roles in pathology. Precisely defining these distinct α-synuclein species will contribute to understanding the molecular origins of these disorders, developing accurate diagnoses, and designing effective therapeutic interventions for these highly debilitating neurodegenerative diseases.

Topics: alpha-Synuclein; Alzheimer Disease; Amyloid; Animals; Humans; Multiple System Atrophy; Parkinson Disease; Protein Aggregation, Pathological

Progressive supranuclear palsy (PSP), multiple system atrophy (MSA), and corticobasal degeneration (CBD) are forms of parkinsonism. PSP and CBD are 4R tauopathies and clinicopathologic overlaps exist between these two disorders. Neuropsychiatric symptoms including apathy, depression, anxiety are common features in patients with PSP and CBD. Disinhibition and impulsive behavior are also frequently observed in PSP patients, whereas hallucinations are seen only occasionally. Severe derangement in several neurotransmitter systems may account for behavioral symptoms observed in PSP and CBD, but substitutive therapy is not effective. Recent advances in genetics, epidemiology, biomarkers, pathophysiology, molecular mechanisms, and, in particular, the availability of treatments that may modify disease progression are opening new hopes in the care of these devastating disorders. MSA is a synucleinopathy with well characterized motor and autonomic dysfunction. MSA patients frequently show the presence of rapid eye movement (REM) behavior disorders, but the impact of neuropsychiatric disturbances and cognitive impairment in MSA needs further study. The availability of animal models and recent advances in the pathophysiology of α-synuclein accumulation are shedding light on the disease, opening new avenues for possible treatments.

Topics: alpha-Synuclein; Basal Ganglia Diseases; Humans; Multiple System Atrophy; Neurodegenerative Diseases; Parkinsonian Disorders; Supranuclear Palsy, Progressive

This review provides an update about cardiac sympathetic denervation in Lewy body diseases. The family of Lewy body diseases includes Parkinson's disease (PD), pure autonomic failure (PAF), and dementia with Lewy bodies (DLB). All three feature intra-neuronal cytoplasmic deposits of the protein, alpha-synuclein. Multiple system atrophy (MSA), the parkinsonian form of which can be difficult to distinguish from PD with orthostatic hypotension, involves glial cytoplasmic inclusions that contain alpha-synuclein. By now there is compelling neuroimaging, neuropathologic, and neurochemical evidence for cardiac sympathetic denervation in Lewy body diseases. In addition to denervation, there is decreased storage of catecholamines in the residual terminals. The degeneration develops in a centripetal, retrograde, "dying back" sequence. Across synucleinopathies the putamen and cardiac catecholaminergic lesions seem to occur independently of each other, whereas non-motor aspects of PD (e.g., anosmia, dementia, REM behavior disorder, OH) are associated with each other and with cardiac sympathetic denervation. Cardiac sympathetic denervation can be caused by synucleinopathy in inherited PD. According to the catecholaldehyde hypothesis, 3,4-dihydroxyphenylacetaldehyde (DOPAL), an intermediary metabolite of dopamine, causes or contributes to the death of catecholamine neurons, especially by interacting with proteins such as alpha-synuclein. DOPAL oxidizes spontaneously to DOPAL-quinone, which probably converts alpha-synuclein to its toxic oligomeric form. Decreasing DOPAL production and oxidation might slow the neurodegenerative process. Tracking cardiac sympathetic innervation over time could be the basis for a proof of principle experimental therapeutics trial targeting DOPAL.

Topics: 3,4-Dihydroxyphenylacetic Acid; alpha-Synuclein; Catecholamines; Dopamine; Heart; Humans; Lewy Bodies; Lewy Body Disease; Multiple System Atrophy; Myocardium; Neuroimaging; Neurons; Parkinson Disease; Sympathetic Nervous System

Alpha-synuclein (α-syn) is a small protein that, in neurons, localizes predominantly to presynaptic terminals. Due to elevated conformational plasticity, which can be affected by environmental factors, in addition to undergoing disorder-to-order transition upon interaction with different interactants, α-syn is counted among the intrinsically disordered proteins (IDPs) family. As with many other IDPs, α-syn is considered a hub protein. This function is particularly relevant at synaptic sites, where α-syn is abundant and interacts with many partners, such as monoamine transporters, cytoskeletal components, lipid membranes, chaperones and synaptic vesicles (SV)-associated proteins. These protein⁻protein and protein⁻lipid membrane interactions are crucial for synaptic functional homeostasis, and alterations in α-syn can cause disruption of this complex network, and thus a failure of the synaptic machinery. Alterations of the synaptic environment or post-translational modification of α-syn can induce its misfolding, resulting in the formation of oligomers or fibrillary aggregates. These α-syn species are thought to play a pathological role in neurodegenerative disorders with α-syn deposits such as Parkinson's disease (PD), dementia with Lewy bodies (DLB), and multiple system atrophy (MSA), which are referred to as synucleinopathies. Here, we aim at revising the complex and promiscuous role of α-syn at synaptic terminals in order to decipher whether α-syn molecular interactants may influence its conformational state, contributing to its aggregation, or whether they are just affected by it.

Topics: alpha-Synuclein; Animals; Humans; Multiple System Atrophy; Neurotransmitter Agents; Parkinson Disease; Protein Binding; Synapses

Synucleinopathies are a group of neurodegenerative diseases characterized by the accumulation of insoluble, aggregated α-synuclein (αS) pathological inclusions. Multiple system atrophy (MSA) presents with extensive oligodendroglial αS pathology and additional more limited neuronal inclusions while most of the other synucleinopathies, such as Parkinson's disease and dementia with Lewy bodies (DLB), develop αS pathology primarily in neuronal cell populations. αS biochemical alterations specific to MSA have been described but thorough examination of these unique and disease-specific protein deposits is further warranted especially given recent findings implicating the prion-like nature of synucleinopathies perhaps with distinct strain-like properties. Taking advantage of an extensive panel of antibodies that target a wide range of epitopes within αS, we investigated the distinct properties of the various types of αS inclusion present in MSA brains with comparison to DLB. Brain biochemical fractionation followed by immunoblotting revealed that the immunoreactive profiles were significantly more consistent for DLB than for MSA. Furthermore, epitope-specific immunohistochemistry varied greatly between different types of MSA αS inclusions and even within different brain regions of individual MSA brains. These studies highlight the importance of using a battery of antibodies for adequate appreciation of the various pathology in this distinct synucleinopathy. In addition, it can be posited that if the spread of pathology in MSA undergoes prion-like mechanisms, "strains" of αS aggregated conformers must be inherently unstable and readily mutable, perhaps resulting in a more stochastic progression process.

Topics: alpha-Synuclein; Brain; Humans; Inclusion Bodies; Multiple System Atrophy

Multiple System Atrophy (MSA) is a severe neurodegenerative disease clinically characterized by parkinsonism, cerebellar ataxia, dysautonomia and other motor and non-motor symptoms.Although several efforts have been dedicated to understanding the causative mechanisms of the disease, MSA pathogenesis remains widely unknown.The aim of the present review is to describe the state of the art about MSA pathogenesis, with a particular focus on alpha-synuclein accumulation and mitochondrial dysfunction, and to highlight future possible perspectives in this field.In particular, this review describes the most widely investigated hypotheses explaining alpha-synuclein accumulation in oligodendrocytes, including SNCA expression, neuron-oligodendrocyte protein transfer, impaired protein degradation and alpha-synuclein spread mechanisms.Afterwards, several recent achievements in MSA research involving mitochondrial biology are described, including the role of COQ2 mutations, Coenzyme Q10 reduction, respiratory chain dysfunction and altered mitochondrial mass.Some hints are provided about alternative pathogenic mechanisms, including inflammation and impaired autophagy.Finally, all these findings are discussed from a comprehensive point of view, putative explanations are provided and new research perspectives are suggested.Overall, the present review provides a comprehensive and up-to-date overview of the mechanisms underlying MSA pathogenesis.

Topics: alpha-Synuclein; Animals; Brain; Humans; Mitochondria; Mitochondrial Diseases; Multiple System Atrophy; Neurons; Oligodendroglia; Synucleinopathies

Alpha-synuclein (αS) is the major constituent of Lewy bodies and a pathogenic hallmark of all synucleinopathathies, including Parkinson's disease (PD), dementia with Lewy bodies (DLB), and multiple system atrophy (MSA). All diseases are determined by αS aggregate deposition but can be separated into distinct pathological phenotypes and diagnostic criteria. Here we attempt to reinterpret the literature, particularly in terms of how αS structure may relate to pathology. We do so in the context of a rapidly evolving field, taking into account newly revealed structural information on both native and pathogenic forms of the αS protein, including recent solid state NMR and cryoEM fibril structures. We discuss how these new findings impact on current understanding of αS and PD, and where this information may direct the field.

Topics: alpha-Synuclein; Brain; Humans; Lewy Bodies; Lewy Body Disease; Multiple System Atrophy; Parkinson Disease

Multiple system atrophy (MSA) is a devastating neurodegenerative disease characterized by the clinical triad of parkinsonism, cerebellar ataxia and autonomic failure, impacting on striatonigral, olivopontocerebellar and autonomic systems. At early stage of the disease, the clinical symptoms of MSA can overlap with those of Parkinson's disease (PD). The key pathological hallmark of MSA is the presence of glial cytoplasmic inclusions (GCI) in oligodendrocytes. GCI comprise insoluble proteinaceous filaments composed chiefly of α-synuclein aggregates, and therefore MSA is regarded as an α-synucleinopathy along with PD and dementia with Lewy bodies. The etiology of MSA is unknown, and the pathogenesis of MSA is still largely speculative. Much data suggests that MSA is a sporadic disease, although some emerging evidence suggests rare genetic variants increase susceptibility. Currently, there is no general consensus on the susceptibility genes as there have been differences due to geographical distribution or ethnicity. Furthermore, many of the reported studies have been conducted on patients that were only clinically diagnosed without pathological verification. The purpose of this review is to bring together available evidence to cross-examine the susceptibility genes and genetic pathomechanisms implicated in MSA. We explore the possible involvement of the SNCA, COQ2, MAPT, GBA1, LRRK2 and C9orf72 genes in MSA pathogenesis, highlight the under-explored areas of MSA genetics, and discuss future directions of research in MSA.

Topics: Alkyl and Aryl Transferases; alpha-Synuclein; Brain; C9orf72 Protein; Genetic Predisposition to Disease; Glucosylceramidase; Humans; Leucine-Rich Repeat Serine-Threonine Protein Kinase-2; Multiple System Atrophy; Neurons; tau Proteins

Multiple system atrophy (MSA) is a progressive neurodegenerative disorder characterised by a variable combination of autonomic failure, levodopa-unresponsive parkinsonism, cerebellar ataxia and pyramidal symptoms. The pathological hallmark is the oligodendrocytic glial cytoplasmic inclusion (GCI) consisting of α-synuclein; therefore, MSA is included in the category of α-synucleinopathies. MSA has been divided into two clinicopathological subtypes: MSA with predominant parkinsonism and MSA with predominant cerebellar ataxia, which generally correlate with striatonigral degeneration and olivopontocerebellar atrophy, respectively. It is increasingly recognised, however, that clinical and pathological features of MSA are broader than previously considered.In this review, we aim to describe recent advances in neuropathology of MSA from a review of the literature and from information derived from review of nearly 200 definite MSA cases in the Mayo Clinic Brain Bank. In light of these new neuropathological findings, GCIs and neuronal cytoplasmic inclusions play an important role in clinicopathological correlates of MSA. We also focus on clinical diagnostic accuracy and differential diagnosis of MSA as well as candidate biomarkers. We also review some controversial topics in MSA. Cognitive impairment, which has been a non-supporting feature of MSA, is considered from both clinical and pathological perspectives. The cellular origin of α-synuclein in GCI and a 'prion hypothesis' are discussed. Finally, completed and ongoing clinical trials targeting disease modification, including immunotherapy, are summarised.

Topics: alpha-Synuclein; Brain; Cerebellar Ataxia; Cognitive Dysfunction; Humans; Inclusion Bodies; Magnetic Resonance Imaging; Multiple System Atrophy; Neurons; Oligodendroglia; Parkinsonian Disorders; Positron-Emission Tomography; Prion Diseases

Multiple system atrophy (MSA) is a rapidly progressive neurodegenerative disorder with a highly variable clinical presentation. Unfortunately, there exists no effective therapy that can improve the course of the disease and symptomatic treatment options remain limited. Although significant progress in research has improved our understanding of MSA, knowledge gaps still remain. Thus, a global network focusing on different research areas is required to face this fatal disease.

Topics: alpha-Synuclein; Animals; Biomarkers; Clinical Trials as Topic; Disease Models, Animal; Humans; Multiple System Atrophy; Translational Research, Biomedical

Multiple system atrophy (MSA) is an orphan, fatal, adult-onset neurodegenerative disorder of uncertain etiology that is clinically characterized by various combinations of parkinsonism, cerebellar, autonomic, and motor dysfunction. MSA is an α-synucleinopathy with specific glioneuronal degeneration involving striatonigral, olivopontocerebellar, and autonomic nervous systems but also other parts of the central and peripheral nervous systems. The major clinical variants correlate with the morphologic phenotypes of striatonigral degeneration (MSA-P) and olivopontocerebellar atrophy (MSA-C). While our knowledge of the molecular pathogenesis of this devastating disease is still incomplete, updated consensus criteria and combined fluid and imaging biomarkers have increased its diagnostic accuracy. The neuropathologic hallmark of this unique proteinopathy is the deposition of aberrant α-synuclein in both glia (mainly oligodendroglia) and neurons forming glial and neuronal cytoplasmic inclusions that cause cell dysfunction and demise. In addition, there is widespread demyelination, the pathogenesis of which is not fully understood. The pathogenesis of MSA is characterized by propagation of misfolded α-synuclein from neurons to oligodendroglia and cell-to-cell spreading in a "prion-like" manner, oxidative stress, proteasomal and mitochondrial dysfunction, dysregulation of myelin lipids, decreased neurotrophic factors, neuroinflammation, and energy failure. The combination of these mechanisms finally results in a system-specific pattern of neurodegeneration and a multisystem involvement that are specific for MSA. Despite several pharmacological approaches in MSA models, addressing these pathogenic mechanisms, no effective neuroprotective nor disease-modifying therapeutic strategies are currently available. Multidisciplinary research to elucidate the genetic and molecular background of the deleterious cycle of noxious processes, to develop reliable biomarkers and targets for effective treatment of this hitherto incurable disorder is urgently needed.

Topics: alpha-Synuclein; Animals; Humans; Multiple System Atrophy; Oligodendroglia

Over the last decade a prominent amount of studies in preclinical transgenic models of multiple system atrophy (MSA) has been performed. These studies have helped understand mechanisms downstream to the α-synuclein oligodendroglial accumulation relevant to human MSA. However, the successful translation of the preclinical outcomes into a clinical trial has failed. Looking back, we can now identify possible confounders for the failure. Biomarkers of disease progression are mostly missing. Early diagnosis and initiation of therapeutic clinical trials is limited. The need of both proof-of-concept as well as clinically relevant preclinical study designs with clinically relevant timing and preclinical readouts is identified as a must in our translational efforts for MSA to date. Finally, improved clinical study designs with improved enrollment criteria, and measurement outcomes are warranted on the way to finding the successful therapeutic approach for MSA. This review provides an overview of experimental studies and clinical trials for MSA and the lessons learned over the last decade towards the identification of the cure for MSA.

Topics: alpha-Synuclein; Animals; Clinical Trials as Topic; Disease Models, Animal; Disease Progression; Humans; Multiple System Atrophy; Translational Research, Biomedical

This study evaluates the relationship between multiple system atrophy and α-synuclein levels in the cerebrospinal fluid, plasma and neural tissue.. Literature search for relevant research articles was undertaken in electronic databases and study selection was based on a priori eligibility criteria. Random-effects meta-analyses of standardized mean differences in α-synuclein levels between multiple system atrophy patients and normal controls were conducted to obtain the overall and subgroup effect sizes. Meta-regression analyses were performed to evaluate the effect of age, gender and disease severity on standardized mean differences.. Data were obtained from 11 studies involving 378 multiple system atrophy patients and 637 healthy controls (age: multiple system atrophy patients 64.14 [95% confidence interval 62.05, 66.23] years; controls 64.16 [60.06, 68.25] years; disease duration: 44.41 [26.44, 62.38] months). Cerebrospinal fluid α-synuclein levels were significantly lower in multiple system atrophy patients than in controls but in plasma and neural tissue, α-synuclein levels were significantly higher in multiple system atrophy patients (standardized mean difference: -0.99 [-1.65, -0.32]; p = 0.001). Percentage of male multiple system atrophy patients was significantly positively associated with the standardized mean differences of cerebrospinal fluid α-synuclein levels (p = 0.029) whereas the percentage of healthy males was not associated with the standardized mean differences of cerebrospinal fluid α-synuclein levels (p = 0.920).. In multiple system atrophy patients, α-synuclein levels were significantly lower in the cerebrospinal fluid and were positively associated with the male gender.

Topics: alpha-Synuclein; Databases, Bibliographic; Humans; Multiple System Atrophy

Multiple system atrophy (MSA) is a fatal neurodegenerative disorder characterized by the abnormal accumulation of toxic forms of the synaptic protein alpha-synuclein (α-syn) within oligodendrocytes and neurons. The presence of α-syn within oligodendrocytes in the form of glial cytoplasmic inclusions is the diagnostic hallmark of MSA. However, it has been postulated that α-syn is produced in neurons and propagates to oligodendrocytes, where unknown mechanisms lead to its accumulation. The presence of α-syn within neurons in MSA has not been so extensively studied, but it may shed light into neuropathological mechanisms leading to oligodendroglial accumulation. Here we summarize the principal neuropathological events of MSA, and discuss how a deeper knowledge of these mechanisms may help develop effective therapies targeting α-syn accumulation and spreading.

Topics: alpha-Synuclein; Animals; Brain; Disease Models, Animal; Humans; Multiple System Atrophy; Neurons; Neuropathology; Oligodendroglia

Through the last decade seven clinical trials on Multiple System Atrophy have been published, virtually all of them reported negative results. Patients and family remain hopeful while facing this devastating disease, but as doctors we still cannot offer them disease-modifying therapies. The field has seen many advances regarding pathophysiology, translational research, diagnostic accuracy, natural history and imaging, but successful treatment remains elusive. This review provides an overview of the available tools for designing clinical trials, critically analyzes the past studies and describes the knowledge obtained from them, and finally gives some orientation for future trials that could meet the current needs of patients and clinicians, overcoming the hurdles met by previous studies.

Topics: alpha-Synuclein; Clinical Trials as Topic; Disease Notification; Humans; Multiple System Atrophy; Translational Research, Biomedical; Treatment Outcome

Iron is essential for cellular development and maintenance of multiple physiological processes in the central nervous system. The disturbance of its homeostasis leads to abnormal iron deposition in the brain and causes neurotoxicity via generation of free radicals and oxidative stress. Iron toxicity has been established in the pathogenesis of Parkinson's disease; however, its contribution to multiple system atrophy (MSA) remains elusive. MSA is characterized by cytoplasmic inclusions of misfolded α-synuclein (α-SYN) in oligodendrocytes referred to as glial cytoplasmic inclusions (GCIs). Remarkably, the oligodendrocytes possess high amounts of iron, which together with GCI pathology make a contribution toward MSA pathogenesis likely. Consistent with this observation, the GCI density is associated with neurodegeneration in central autonomic networks as well as olivopontocerebellar and striatonigral pathways. Iron converts native α-SYN into a β-sheet conformation and promotes its aggregation either directly or via increasing levels of oxidative stress. Interestingly, α-SYN possesses ferrireductase activity and α-SYN expression underlies iron mediated translational control via RNA stem loop structures. Despite a correlation between progressive putaminal atrophy and iron accumulation as well as clinical decline, it remains unclear whether pathologic iron accumulation in MSA is a secondary event in the cascade of neuronal degeneration rather than a primary cause. This review summarizes the current knowledge of iron in MSA and gives evidence for perturbed iron homeostasis as a potential pathogenic factor in MSA-associated neurodegeneration.

Topics: alpha-Synuclein; Brain; Humans; Inclusion Bodies; Iron; Magnetic Resonance Imaging; Multiple System Atrophy; Oligodendroglia; Parkinsonian Disorders

This article reviews the epidemiological evidence of features of α-synucleinopathies that precede clinical onset of disease, proposes a clinical timeline, and attempts to define the different premotor and clinical phenotypes associated with α-synucleinopathies.. The pathological hallmarks of the α-synucleinopathies (Parkinson disease, Parkinson disease dementia, dementia with Lewy bodies, and multisystem atrophy) begin years before a clinical diagnosis. Epidemiologic studies support the long gap between pathology and symptoms and suggest that certain nonmotor conditions (constipation, anxiety, and rapid eye movement sleep behavior disorder) precede the traditional motor Parkinson disease phenotype by long intervals.. Characterizing the temporal onset of these conditions will help to better recognize the premotor phase of the α-synucleinopathies and specific clinical phenotypes and will guide the search for predictive biomarkers and risk or protective factors for Parkinson disease and other synucleinopathies.

Topics: alpha-Synuclein; Dementia; Humans; Multiple System Atrophy; Parkinsonian Disorders

Mutations in the leucine rich repeat kinase 2 (LRRK2) gene are among the most common genetic causes of Lewy body Parkinson's disease (PD). However, LRRK2 mutations can also lead to a variety of pathological phenotypes other than typical PD, including relatively pure nigrostriatal cell loss without alpha-synuclein-positive Lewy bodies or Lewy neurites, progressive supranuclear palsy (PSP), and multiple system atrophy (MSA). The mechanisms behind this remarkable pleomorphic pathology are currently unclear.. To genetically and pathologically characterize a case with a LRRK2, p.Ile1371Val rare variant and pathologically proven MSA.. From the brain donation program at the Parkinson's Institute and Clinical Center, we selected 26 brains with family history and a with clinicopathological diagnosis of PD (n = 20), MSA (n = 4), or PSP (n = 2). We performed neuropathological evaluation, including alpha-synuclein and tau immunohistochemistry and sequenced 188 genes that have been reported as causative for or associated with neurodegenerative diseases.. We identified a known LRRK2, p.Ile1371Val genetic variant in a case with clinically diagnosed and pathologically proven MSA. Neuropathology revealed that the olivopontocerebellar system was more affected than the striatonigral system.. Our data suggest that genetic variants in the LRRK2 gene can present clinically and neuropathologically as MSA. One other LRRK2 genetic variant (LRRK2, p.Ile2020Thr) has been reported with a neuropathological diagnosis of MSA. Interestingly, the LRRK2 variant (LRRK2, p.Ile1371Val) identified here has been reported previously in a postmortem case with Lewy body PD.Future studies are critical to discover the mechanisms leading to different neurodegenerative trajectories both in neuronal and glial cell populations.

Topics: alpha-Synuclein; Brain; Brain Chemistry; Female; Humans; Leucine-Rich Repeat Serine-Threonine Protein Kinase-2; Middle Aged; Multiple System Atrophy; Mutation, Missense; Neuroglia; Neurons; Pedigree; Point Mutation; Sequence Analysis, DNA; tau Proteins

Several age-related neurodegenerative disorders are characterized by the deposition of aberrantly folded endogenous proteins. These proteins have prion-like propagation and amplification properties but so far appear nontransmissible between individuals. Because of the features they share with the prion protein, PrP, the characteristics of pathogenic protein aggregates in several progressive brain disorders, including different types of Lewy body diseases (LBDs), such as Parkinson's disease (PD), multiple system atrophy (MSA) and dementia with Lewy bodies (DLB), have been actively investigated. Even though the pleomorphic nature of these syndromes might suggest different underlying causes, ɑ-synuclein (ɑSyn) appears to play an important role in this heterogeneous group of diseases (the synucleinopathies). An attractive hypothesis is that different types of ɑSyn protein assemblies have a unique and causative role in distinct synucleinopathies. We will discuss the recent research progress on ɑSyn assemblies involved in PD, MSA and DLB; their behavior as strains; current spreading hypotheses; their ability to seed centrally and peripherally; and their implication for disease pathogenesis.

Topics: alpha-Synuclein; Animals; Humans; Lewy Body Disease; Multiple System Atrophy; Parkinson Disease; Prions; Protein Aggregates

Rapid eye movement (REM) sleep behavior disorder (RBD) involves REM sleep without atonia in conjunction with a recurrent nocturnal dream enactment behavior, with vocalizations such as shouting and screaming, and motor behaviors such as punching and kicking. Secondary RBD is well described in association with neurological disorders including Parkinson's disease (PD), multiple system atrophy (MSA), and other conditions involving brainstem structures such as tumors. However, RBD alone is now considered to be a potential harbinger of later development of neurodegenerative disorders, in particular PD, MSA, dementia with Lewy bodies (DLB), and pure autonomic failure. These conditions are linked by their underpinning pathology of alpha-synuclein protein aggregation. In RBD, it is therefore important to recognize the potential risk for later development of an alpha-synucleinopathy, and to investigate for other potential causes such as medications. Other signs and symptoms have been described in RBD, such as orthostatic hypotension, or depression. While it is important to recognize these features to improve patient management, they may ultimately provide clinical clues that will lead to risk stratification for phenoconversion. A critical need is to improve our ability to counsel patients, particularly with regard to prognosis. The ability to identify who, of those with RBD, is at high risk for later neurodegenerative disorders will be paramount, and would in addition advance our understanding of the prodromal stages of the alpha-synucleinopathies. Moreover, recognition of at-risk individuals for neurodegenerative disorders may ultimately provide a platform for the testing of possible neuroprotective agents for these neurodegenerative disorders.

Topics: alpha-Synuclein; Cross-Sectional Studies; Electroencephalography; Humans; Lewy Body Disease; Longitudinal Studies; Multiple System Atrophy; Parkinson Disease; REM Sleep Behavior Disorder

Multiple system atrophy, characterized by atypical Parkinsonism, results from central nervous system (CNS) cell loss and dysfunction linked to aggregates of the normally pre-synaptic α-synuclein protein. Mostly cytoplasmic pathological α-synuclein inclusion bodies occur predominantly in oligodendrocytes in affected brain regions and there is evidence that α-synuclein released by neurons is taken up preferentially by oligodendrocytes. However, extracellular α-synuclein has also been shown to interact with other neural cell types, including astrocytes and microglia, as well as extracellular factors, mediating neuroinflammation, cell-to-cell spread and other aspects of pathogenesis. Here, we review the current evidence for how α-synuclein present in the extracellular milieu may act at the cell surface to drive components of disease progression. A more detailed understanding of the important extracellular interactions of α-synuclein with neuronal and non-neuronal cell types both in the brain and periphery may provide new therapeutic targets to modulate the disease process.

Topics: alpha-Synuclein; Animals; Astrocytes; Extracellular Space; Humans; Microglia; Multiple System Atrophy; Neurons; Oligodendroglia

Topics: alpha-Synuclein; Gene Expression; Genome-Wide Association Study; Humans; Lewy Body Disease; Multiple System Atrophy; Mutation; Parkinson Disease; Phenotype

Multiple system atrophy (MSA) is a rapidly progressive neurodegenerative disease arising from the misfolding and accumulation of the protein α-synuclein in oligodendrocytes, where it forms glial cytoplasmic inclusions (GCIs). Several years of studying synthetic α-synuclein fibrils has provided critical insight into the ability of α-synuclein to template endogenous protein misfolding, giving rise to fibrillar structures capable of propagating from cell to cell. However, more recent studies with MSA-derived α-synuclein aggregates have shown that they have a similar ability to undergo template-directed propagation, like PrP prions. Almost 20 years after α-synuclein was discovered as the primary component of GCIs, α-synuclein aggregates isolated from MSA patient samples were shown to infect cultured mammalian cells and also to transmit neurological disease to transgenic mice. These findings argue that α-synuclein becomes a prion in MSA patients. In this review, we discuss the in vitro and in vivo data supporting the recent classification of MSA as a prion disease.

Topics: alpha-Synuclein; Animals; Cells, Cultured; Disease Models, Animal; Humans; Mice; Mice, Transgenic; Multiple System Atrophy; Prion Diseases; Prions

Starting two decades ago with the discoveries of genetic links between alpha-synuclein and Parkinson's disease risk and the identification of aggregated alpha-synuclein as the main protein constituent of Lewy pathology, alpha-synuclein has emerged as the major therapeutic target in Parkinson's disease and related synucleinopathies. Following the suggestion that alpha-synuclein pathology gradually spreads through the nervous system following a stereotypic pattern and the discovery that aggregated forms of alpha-synuclein can propagate pathology from one cell to another, and thereby probably aggravate existing deficits as well as generate additional symptoms, the idea that alpha-synuclein is a viable therapeutic target gained further support. In this review we describe current challenges and possibilities with alpha-synuclein as a therapeutic target. We briefly highlight gaps in the knowledge of the role of alpha-synuclein in disease, and propose that a deeper understanding of the pathobiology of alpha-synuclein can lead to improved therapeutic strategies. We describe several treatment approaches that are currently being tested in advanced animal experiments or already are in clinical trials. We have divided them into approaches that reduce alpha-synuclein production; inhibit alpha-synuclein aggregation inside cells; promote its degradation either inside or outside cells; and reduce its uptake by neighbouring cells following release from already affected neurons. Finally, we briefly discuss challenges related to the clinical testing of alpha-synuclein therapies, for example difficulties in monitoring target engagement and the need for relatively large trials of long duration. We conclude that alpha-synuclein remains one of the most compelling therapeutic targets for Parkinson's disease, and related synucleinopathies, and that the multitude of approaches being tested provides hope for the future.

Topics: alpha-Synuclein; Animals; Disease Models, Animal; Genetic Therapy; Humans; Multiple System Atrophy; Neurons; Parkinson Disease

Parkinson's disease (PD), dementia with Lewy Bodies (DLB), and multiple system atrophy (MSA) are three major synucleinopathies characterized by α-synuclein-containing inclusions in the brains of patients. Because the cell types and brain structures that are affected vary markedly between the disorders, the patients have different clinical manifestations in addition to some overlapping symptoms, which are the basis for differential diagnosis. Cognitive impairment and depression associated with hippocampal dysfunction are frequently observed in these disorders. While various α-synuclein-containing inclusions are found in the hippocampal formation, increasing evidence supports that small α-synuclein aggregates or oligomers may be the real culprit, causing deficits in neurotransmission and neurogenesis in the hippocampus and related brain regions, which constitute the major mechanism for the hippocampal dysfunctions and associated neuropsychiatric manifestations in synucleinopathies.

Topics: alpha-Synuclein; Animals; Hippocampus; Humans; Inclusion Bodies; Lewy Body Disease; Multiple System Atrophy; Neurogenesis; Parkinson Disease; Protein Aggregates; Protein Aggregation, Pathological; Synaptic Transmission

Alterations in α-synuclein dosage lead to familial Parkinson's disease (PD), and its accumulation results in synucleinopathies that include PD, dementia with Lewy bodies (DLB) and multiple system atrophy (MSA). Furthermore, α-synuclein contributes to the fibrilization of amyloid-b and tau, two key proteins in Alzheimer's disease, which suggests a central role for α-synuclein toxicity in neurodegeneration. Recent studies of factors contributing to α-synuclein toxicity and its disruption of downstream cellular pathways have expanded our understanding of disease pathogenesis in synucleinopathies. In this Review, we discuss these emerging themes, including the contributions of aging, selective vulnerability and non-cell-autonomous factors such as α-synuclein cell-to-cell propagation and neuroinflammation. Finally, we summarize recent efforts toward the development of targeted therapies for PD and related synucleinopathies.

Topics: alpha-Synuclein; Alzheimer Disease; Amyloid beta-Peptides; Autophagy; Axonal Transport; Endoplasmic Reticulum; Golgi Apparatus; Humans; Lewy Body Disease; Lysosomes; Mitochondria; Molecular Targeted Therapy; Multiple System Atrophy; Neurons; Parkinson Disease; Protein Aggregates; Protein Aggregation, Pathological; Synapses; tau Proteins

Intracellular aggregates of the α-synuclein protein result in cell loss and dysfunction in Parkinson's disease and atypical Parkinsonism, such as multiple system atrophy and dementia with Lewy bodies. Each of these neurodegenerative conditions, known collectively as α-synucleinopathies, may be characterized by a different suite of molecular triggers that initiate pathogenesis. The mechanisms whereby α-synuclein aggregates mediate cytotoxicity also remain to be fully elucidated. However, recent studies have implicated the cell-to-cell spread of α-synuclein as the major mode of disease propagation between brain regions during disease progression. Here, we review the current evidence for different modes of α-synuclein cellular release, movement and uptake, including exocytosis, exosomes, tunneling nanotubes, glymphatic flow and endocytosis. A more detailed understanding of the major modes by which α-synuclein pathology spreads throughout the brain may provide new targets for therapies that halt the progression of disease.

Topics: alpha-Synuclein; Animals; Astrocytes; Cell Communication; Exosomes; Extracellular Space; Humans; Intracellular Space; Lewy Bodies; Lewy Body Disease; Microglia; Models, Biological; Multiple System Atrophy; Parkinson Disease; Protein Aggregation, Pathological; Protein Binding; Protein Transport

In 2017, it is two hundred years since James Parkinson provided the first complete clinical description of the disease named after him, fifty years since the introduction of high-dose D,L-DOPA treatment and twenty years since α-synuclein aggregation came to the fore. In 1998, multiple system atrophy joined Parkinson's disease and dementia with Lewy bodies as the third major synucleinopathy. Here we review our work, which led to the identification of α-synuclein in Lewy bodies, Lewy neurites and Papp-Lantos bodies, as well as what has happened since. Some of the experiments described were carried out in collaboration with ML Schmidt, JQ Trojanowski and VMY Lee.

Topics: alpha-Synuclein; History, 20th Century; History, 21st Century; Humans; Lewy Body Disease; Multiple System Atrophy; Parkinson Disease

Vaccination is increasingly being investigated as a potential treatment for synucleinopathies, a group of neurodegenerative diseases including Parkinson's disease, multiple system atrophy, and dementia with Lewy bodies associated with α-synuclein pathology. All lack a causal therapy. Development of novel, disease-altering treatment strategies is urgently needed. Vaccination has positioned itself as a prime strategy for addressing these diseases because it is broadly applicable, requires infrequent administration, and maintains low production costs for treating a large population or as a preventive measure. Current evidence points to a causal role of misfolded α-synuclein in the development and progression of synucleinopathies. In the past decade, significant progress in active immunization against α-synuclein has been shown both in preclinical animal models and in early clinical development. In this review, we describe the state-of-the-art in active immunization approaches to synucleinopathies, with a focus on advances in Parkinson's disease (PD) and multiple-system atrophy (MSA). We first review preclinical animal models, highlighting their progress in translation to the clinical setting. We then discuss current clinical applications, stressing different approaches taken to address α-synuclein pathology. Finally, we address challenges, trends, and future perspectives of current vaccination programs.

Topics: alpha-Synuclein; Animals; Humans; Multiple System Atrophy; Parkinson Disease; Vaccination

Currently there are no disease-modifying alternatives for the treatment of most neurodegenerative disorders. The available therapies for diseases such as Parkinson's disease (PD), PD dementia (PDD), dementia with Lewy bodies (DLB), and multiple system atrophy (MSA), in which the protein alpha-synuclein (α-Syn) accumulates within neurons and glial cells with toxic consequences, are focused on managing the disease symptoms. However, using strategic drug combinations and/or multi-target drugs might increase the treatment efficiency when compared with monotherapies. Synucleinopathies are complex disorders that progress through several stages, and toxic α-Syn aggregates exhibit prion-like behavior spreading from cell to cell. Therefore, it follows that these neurodegenerative disorders might require equally complex therapeutic approaches to obtain significant and long-lasting results. Hypothetically, therapies aimed at reducing α-Syn accumulation and cell-to-cell transfer, such as immunotherapy against α-Syn, could be combined with agents that reduce neuroinflammation with potential synergistic outcomes. Here we review the current evidence supporting this type of approach, suggesting that such rational therapy combinations, together with the use of multi-target drugs, may hold promise as the next logical step for the treatment of synucleinopathies.

Topics: alpha-Synuclein; Animals; Combined Modality Therapy; Humans; Immunotherapy; Lewy Body Disease; Multiple System Atrophy; Parkinson Disease

Synucleinopathies are characterized by abnormal proteinaceous aggregates, mainly composed of fibrillar α-synuclein (α-syn). It is now believed that α-syn can form small aggregates in a restricted number of cells, that propagate to neighbouring cells and seed aggregation of endogenous α-syn, in a 'prion-like manner'. This process could underlie the stereotypical progression of Lewy bodies described by Braak and colleagues across different stages of Parkinson's disease (PD). This prion-like behaviour of α-syn has been recently investigated in animal models of PD or multiple system atrophy (MSA). These models investigate the cell-to-cell transfer of α-syn seeds, or the induction and spreading of α-syn pathology in transgenic or wild-type rodent brain. In this review, we first outline the involvement of α-syn in Lewy body diseases and MSA, and discuss how 'prion-like' mechanisms can contribute to disease. Thereon, we debate the relevance of animal models used to study prion-like propagation. Finally, we review current main histological methods used to assess α-syn pathology both in animal models and in human samples and their relevance to the disease. Specifically, we discuss using α-syn phosphorylated at serine 129 as a marker of pathology, and the novel methods available that allow for more sensitive detection of early pathology, which has relevance for modelling synucleinopathies.

Topics: alpha-Synuclein; Animals; Disease Models, Animal; Disease Progression; Humans; Lewy Body Disease; Multiple System Atrophy

Immunotherapy using antibodies targeting alpha-synuclein has proven to be an effective strategy for ameliorating pathological and behavioral deficits induced by excess pathogenic alpha-synuclein in various animal and/or cellular models. However, the process of selecting the anti-alpha-synuclein antibody with the best potential to treat synucleinopathies in humans is not trivial. Critical to this process is a better understanding of the pathological processes involved in the synucleinopathies and how antibodies are able to influence these. We will give an overview of the first proof-of-concept studies in rodent disease models and discuss challenges associated with developing antibodies against alpha-synuclein resulting from the distribution and structural characteristics of the protein. We will also provide a status on the passive immunization approaches targeting alpha-synuclein that have entered, or are expected to enter, clinical evaluation.

Topics: alpha-Synuclein; Animals; Disease Models, Animal; Immunization, Passive; Lewy Body Disease; Multiple System Atrophy; Parkinson Disease

The lack of effective therapies for neurodegenerative disorders is one of the most relevant challenges of this century, considering that, as the global population ages, the incidence of these type of diseases is quickly on the rise. Among these disorders, synucleinopathies, which are characterized by the abnormal accumulation and spreading of the synaptic protein alpha-synuclein in the brain, already constitute the second leading cause of parkinsonism and dementia in the elderly population. Disorders with alpha-synuclein accumulation include Parkinson's disease, dementia with Lewy bodies and multiple system atrophy. Numerous therapeutic alternatives for synucleinopathies are being tested in pre-clinical models and in the clinic; however, only palliative treatments addressing the dopaminergic deficits are approved to date, and no disease-modifying options are available yet. In this article, we provide a brief overview of therapeutic approaches currently being explored for synucleinopathies, and suggest possible explanations to the clinical trials outcomes. Finally, we propose that a deeper understanding of the pathophysiology of synucleinopathies, together with a combination of therapies tailored to each disease stage, may lead to better therapeutic outcomes in synucleinopathy patients. Synucleinopathies, neurodegenerative disorders characterized by the abnormal accumulation of the protein alpha-synuclein, constitute the second leading cause of parkinsonism and dementia in the elderly population, however, no disease-modifying options are available yet. In this review, we summarize the therapeutic approaches currently being explored for synucleinopathies, suggest possible explanations to the clinical outcomes, and propose areas of further therapeutic improvement. This article is part of a special issue on Parkinson disease.

Topics: alpha-Synuclein; Animals; Clinical Trials as Topic; Dementia; Genetic Therapy; Humans; Lewy Body Disease; Multiple System Atrophy; Parkinson Disease; Stem Cell Transplantation

It has been recognized for many years that a number of chronic neurodegenerative diseases of the CNS are characterized by the development of intracellular inclusion bodies, but it is only relatively recently that the core proteins defining these pathologies have been defined. One such protein is alpha synuclein, that was found to be the main component of Lewy bodies in the late 1990s, and this discovery reinforced the emerging view that alpha synuclein was intimately linked to diseases characterized by this type of pathology--namely Parkinson's disease (PD) and Dementia with Lewy Bodies (DLB). Furthermore at around this time, this same protein was also found within the glial inclusion bodies of patients dying with multiple system atrophy (MSA). These three disorders constitute the majority of patients with an 'alpha synucleinopathy', although there are a number of rarer conditions that can also cause this pathology including inherited metabolic disorders such as Gaucher's disease (GD). In this review, we will concentrate on PD, the commonest alpha synucleinopathy, and its associated dementia (PDD), as well as discussing DLB and MSA and will highlight how the clinical features of these conditions vary as a function of pathology.

Topics: alpha-Synuclein; Humans; Lewy Body Disease; Multiple System Atrophy; Parkinson Disease

Multiple system atrophy (MSA) is a fatal orphan neurodegenerative disorder that manifests with rapidly progressive autonomic and motor dysfunction. The disease is characterized by the accumulation of α-synuclein fibrils in oligodendrocytes that form glial cytoplasmic inclusions, a neuropathological hallmark and central player in the pathogenesis of MSA. Here, we summarize the current knowledge on the etiopathogenesis and neuropathology of MSA. We discuss the role of α-synuclein pathology, microglial activation, oligodendroglial dysfunction and putative cell death mechanisms as candidate therapeutic targets in MSA.

Topics: alpha-Synuclein; Animals; Humans; Multiple System Atrophy

Multiple system atrophy (MSA) is a rare, yet rapidly-progressive neurodegenerative disease that presents clinically with autonomic failure in combination with parkinsonism or cerebellar ataxia. The definitive neuropathology differentiating MSA from Lewy body diseases is the presence of α-synuclein aggregates in oligodendrocytes (called glial cytoplasmic inclusion or GCI) rather than the fibrillar aggregates in neurons (called Lewy bodies). This makes the pathological pathway(s) in MSA unique in that oligodendrocytes are involved rather than predominantly neurons, as is most other neurodegenerative disorders. MSA is therefore regarded as an oligodendrogliopathy. The etiology of MSA is unknown. No definitive risk factors have been identified, although α-synuclein and other genes have been variably linked to MSA risk. Utilization of postmortem brain tissues has greatly advanced our understanding of GCI pathology and the subsequent neurodegeneration. However, extrapolating the early pathogenesis of MSA from such resource has been difficult and limiting. In recent years, cell and animal models developed for MSA have been instrumental in delineating unique MSA pathological pathways, as well as aiding in clinical phenotyping. The purpose of this review is to bring together and discuss various animal models that have been developed for MSA and how they have advanced our understanding of MSA pathogenesis, particularly the dynamics of α-synuclein aggregation. This review will also discuss how animal models have been used to explore potential therapeutic avenues for MSA, and future directions of MSA modeling.

Topics: alpha-Synuclein; Animals; Disease Models, Animal; Humans; Multiple System Atrophy; Oligodendroglia

In this review the structural and functional imaging changes associated with the synucleinopathies PD, MSA, and dementias associated with Lewy bodies are reviewed. The role of imaging for supporting differential diagnosis, detecting subclinical disease, and following disease progression is discussed and its potential use for monitoring disease progression is debated. © 2016 International Parkinson and Movement Disorder Society.

Topics: alpha-Synuclein; Humans; Lewy Body Disease; Multiple System Atrophy; Parkinson Disease; Substantia Nigra

Mutations in the F-box only protein 7 (FBXO7) gene, located on chromosome 22q12-q13, have recently been identified as having distinct clinical features in patients with hereditary Parkinson's disease (PD). Pathologically, α-synuclein-positive inclusions have been identified using anti-FBXO7 antibody staining techniques. In the present study, we screened entire exons of FBXO7 from 271 patients (231 PD and 40 multiple system atrophy [MSA]), of which 221 samples were of Japanese origin. The PD patients (n = 231) comprised 31 autosomal dominant, 82 autosomal recessive, and 118 sporadic forms. The 40 cases of MSA consisted of 8 autosomal dominant, 2 autosomal recessive, and 30 sporadic forms. We detected a Turkish patient with autosomal recessive inheritance, harboring a homozygous truncating mutation, Arg498Stop (p.R498X), in the FBXO7 gene. Consequently, we evaluated her and assessed the correlation between her clinical manifestations and genotypic analysis, although the FBXO7 p.R498X gene has lower frequency than others. Her age at onset was 17 years, and she clinically manifested with progressive parkinsonism and cognitive decline. In contrast, no pathogenic mutations in FBXO7 among PD and MSA patients of Japanese or other ethnicities were observed. Based on recent literature, we reviewed and compared the clinical findings and population differences between documented FBXO7 cases.

Topics: Adolescent; Adult; Aged; alpha-Synuclein; Chromosomes, Human, Pair 22; F-Box Proteins; Female; Genes, Dominant; Genes, Recessive; Genetic Association Studies; Humans; Japan; Male; Middle Aged; Multiple System Atrophy; Mutation; Parkinson Disease; Turkey; Young Adult

Several decades ago, a mysterious transmissible agent was found responsible for a group of progressive and lethal encephalopathies affecting the nervous system of both animals and humans. This infectious agent showed a strain-encoded manner of inheritance even though it lacked nucleic acids. The identification of infectious proteins resolved this apparent conundrum. Misfolded infectious protein particles, or prions, were found to exist as conformational isomers with a unique fingerprint that can be faithfully passaged to next generations. Protein-based strain-encoded inheritance is characterized by strain-specific infectivity and symptomatology. It is found in diverse organisms, such as yeast, fungi, and mammals. Now, this concept is revisited to examine the pathological role of amyloid proteins involved in neurodegenerative diseases where it might underlie certain types of dementia and motor-related neurodegenerative disorders. Given the discovery of the SNCA gene and the identification of its gene product, ɑ-synuclein (ɑ-SYN), as the main histopathological component of Parkinson's disease, dementia with Lewy bodies and multiple system atrophy, the scientific community was left puzzled by the fact that a single protein appeared to be involved in different diseases with diverging clinical phenotypes. Recent studies are now indicating that ɑ-SYN may act in a way similar to prions and that ɑ-SYN misfolded structural variants may behave as strains with distinct biochemical and functional properties inducing specific phenotypic traits, which might finally provide an explanation for the clinical heterogeneity observed between Parkinson's disease, MSA, and dementia with Lewy bodies patients. These crucial new findings may pave the way for unexplored therapeutic avenues and identification of new potential biomarkers. Parkinson's disease and other synucleinopathies share ɑ-synuclein deposits as a common histopathological hallmark. New and ongoing developments are now showing that variations in the aggregation process and the formation of ɑ-synuclein strains may be paralleled by the development of distinct synucleinopathies. Here, we review the recent developments and the role of strains in synucleinopathies. This article is part of a special issue on Parkinson disease.

Topics: alpha-Synuclein; Animals; Dementia; Genetic Variation; Humans; Lewy Body Disease; Multiple System Atrophy; Neurodegenerative Diseases; Parkinson Disease

Neurodegenerative disorders with alpha-synuclein (α-syn) accumulation (synucleinopathies) include Parkinson's disease (PD), PD dementia, dementia with Lewy bodies and multiple system atrophy (MSA). Due to the involvement of toxic α-syn aggregates in the molecular origin of these disorders, developing effective therapies targeting α-syn is a priority as a disease-modifying alternative to current symptomatic treatments. Importantly, the clinical and pathological attributes of MSA make this disorder an excellent candidate as a synucleinopathy model for accelerated drug development. Recent therapeutic strategies targeting α-syn in in vivo and in vitro models of MSA, as well as in clinical trials, have been focused on the pathological mechanisms of α-syn synthesis, aggregation, clearance, and/or cell-to-cell propagation of its neurotoxic conformers. Here we summarize the most relevant approaches in this direction, with emphasis on their potential as general synucleinopathy modifiers, and enumerate research areas for potential improvement in MSA drug discovery.

Topics: alpha-Synuclein; Animals; Disease Models, Animal; Humans; Multiple System Atrophy

Synucleinopathies are a group of neurodegenerative diseases that share a common pathological lesion of intracellular protein inclusions largely composed by aggregates of alpha-synuclein protein. Accumulating evidence, including genome wide association studies, has implicated alpha-synuclein (SNCA) gene in the etiology of synucleinopathies. However, the precise variants within SNCA gene that contribute to the sporadic forms of Parkinson's disease (PD), dementia with Lewy bodies (DLB), multiple system atrophy (MSA), and other synucleinopathies and their molecular mechanisms of action remain elusive. It has been suggested that SNCA expression levels are critical for the development of these diseases. Here, we review several model systems that have been developed to advance the understanding of the role of SNCA expression levels in the etiology of synucleinopathies. We also describe different molecular mechanisms that regulate SNCA gene expression and discuss possible strategies for SNCA down-regulation as means for therapeutic approaches. Finally, we highlight some examples that underscore the relationships between the genetic association findings and the regulatory mechanisms of SNCA expression, which suggest that genetic variability in SNCA locus is directly responsible, at least in part, to the changes in gene expression and explain the reported associations of SNCA with synucleinopathies. Future studies utilizing induced pluripotent stem cells (iPSCs)-derived neuronal lines and genome editing by CRISPR/Cas9, will allow us to validate, characterize, and manipulate the effects of particular cis-genetic variants on SNCA expression. Moreover, this model system will enable us to compare different neuronal and glial lineages involved in synucleinopathies representing an attractive strategy to elucidate-common and specific-SNCA-genetic variants, regulatory mechanisms, and vulnerable expression levels underlying synucleinopathy spectrum disorders. This forthcoming knowledge will support the development of precision medicine for synucleinopathies.

Topics: alpha-Synuclein; Animals; Epigenesis, Genetic; Gene Expression; Gene Expression Regulation; Humans; Lewy Body Disease; Multiple System Atrophy; Parkinson Disease; Protein Aggregation, Pathological; Up-Regulation

Abnormal accumulation of proteinaceous intraneuronal inclusions called Lewy bodies (LBs) is the neurpathological hallmark of Parkinson's disease (PD) and related synucleinopathies. These inclusions are mainly constituted of a presynaptic protein, α-synuclein (α-syn). Over the past decade, growing amounts of studies reported an aberrant accumulation of phosphorylated α-syn at the residue S129 (pS129) in the brain of patients suffering from PD, as well as in transgenic animal models of synucleinopathies. Whereas only a small fraction of α-syn (<4%) is phosphorylated in healthy brains, a dramatic accumulation of pS129 (>90%) has been observed within LBs, suggesting that this post-translational modification may play an important role in the regulation of α-syn aggregation, LBs formation and neuronal degeneration. However, whether phosphorylation at S129 suppresses or enhances α-syn aggregation and toxicity in vivo remains a subject of active debate. The answer to this question has important implications for understanding the role of phosphorylation in the pathogenesis of synucleinopathies and determining if targeting kinases or phosphatases could be a viable therapeutic strategy for the treatment of these devastating neurological disorders. In the present review, we explore recent findings from in vitro, cell-based assays and in vivo studies describing the potential implications of pS129 in the regulation of α-syn physiological functions, as well as its implication in synucleinopathies pathogenesis and diagnosis.

Topics: alpha-Synuclein; Animals; Brain; Humans; Lewy Bodies; Lewy Body Disease; Multiple System Atrophy; Parkinson Disease; Phosphorylation

The diagnostic criteria currently used for Parkinson's disease (PD) are mainly based on clinical motor symptoms. For these reasons many biomarkers are under investigation to support the diagnosis at the early stage. The neuropathological hallmark of PD is represented by Lewy bodies (LBs), which are intracytoplasmic inclusions in substantia nigra neurons. The major component of LBs, α-synuclein (α-syn), has been implicated in the pathogenesis of PD and in other 'synucleinopathies' such as multisystem atrophy (MSA) and dementia with LBs (DLBs). Several studies have investigated this presynaptic protein as a potential biomarker of PD. The aim of our meta-analysis is to determine the ability of cerebrospinal fluid (CSF) concentrations of total α-syn, oligomeric α-syn and phosphorylated α-syn to discriminate patients with PD from healthy participants, non-degenerative neurological controls and patients suffering from parkinsonism and or synucleinopathies.. This systematic review protocol has been developed according to the Preferred Reporting Items for Systematic reviews and Meta-Analyses Protocol (PRISMA-P) 2015 statement and was registered on PROSPERO (CRD42016013217). We will search Cochrane Library, Web of Science, MEDLINE (via PubMed) and EMBASE from inception, using appropriate search strategies. Two independent reviewers will screen titles, abstracts and full-text articles, and will complete data abstraction. We will include studies that involved patients with PD, DLB, MSA, progressive supranuclear palsy, corticobasal disease and vascular PD, and in which at least one between total α-syn, oligomeric α-syn and phosphorylated α-syn was measured in CSF. To evaluate the risk of bias and applicability of primary diagnostic accuracy studies, we will use QUADAS-2.. Our study will not include confidential data, and no intervention will be involved, so ethical approval is not required. The results of the study will be reported in international peer-reviewed journals.

Topics: alpha-Synuclein; Biomarkers; Diagnosis, Differential; Humans; Lewy Bodies; Multiple System Atrophy; Parkinson Disease; Research Design; Systematic Reviews as Topic

α-Synuclein, which is present as a small, soluble, cytosolic protein in healthy subjects, is converted to amyloid-like fibrils in diseases such as Parkinson's disease (PD), dementia with Lewy bodies (DLB), and multiple system atrophy (MSA). Bulk synthesis of purified α-synuclein has made it more convenient to study the nature of the normal protein and the mechanism of its conversion to an abnormal form in vitro and in vivo. Synthetic α-synuclein fibrils and pathological α-synuclein from diseased brains can act as triggers to convert normal α-synuclein to an abnormal form via prion-like mechanisms. In this article, we describe the experimental pathologies of α-synuclein both in vitro and in vivo in human and animal models. Prion-like spreading of abnormal α-synuclein from cell to cell can account for the progression of these α-synucleinopathies.

Topics: alpha-Synuclein; Amyloid; Animals; Brain; Disease Models, Animal; Disease Progression; Humans; Lewy Body Disease; Mice; Multiple System Atrophy; Parkinson Disease

Parkinson's disease, dementia with Lewy bodies and multiple system atrophy are characterised by abnormal neuroglial α-synuclein accumulation. These α-synucleinopathies have in common parkinsonism and non-motor features including orthostatic hypotension (OH) and cognitive impairment. However, the nature of the relationship between OH and cognitive impairment is unclear. We therefore systematically reviewed the literature for evidence of an association between OH and cognitive impairment in α-synucleinopathies and discuss possible mechanisms and implications of this relationship. Abstracts from 313 original research articles were surveyed, and a total of 132 articles were considered for this review. Articles were stratified as: 'direct-evidence studies' based on the direct assessment for a relationship between OH and cognitive impairment in α-synucleinopathies, and 'indirect-evidence studies' based on an association being referred to as a secondary outcome. Ten 'direct-evidence papers' were identified, seven of which reported a positive association between OH and cognitive impairment, while seven of 12 'indirect-evidence papers' similarly did as well. The papers that reported no association between OH and cognitive impairment used less sensitive measures of cognition. A relationship between OH and cognitive impairment in patients with α-synucleinopathies exists, but the underlying mechanisms remain unclear. Three hypotheses are proposed: (1) OH and cognitive impairment occur concurrently due to diffuse brain and peripheral deposition of α-synuclein, (2) OH-mediated cerebral hypoperfusion impairs cognition and (3) the two act synergistically to accelerate cognitive decline. Longitudinal neuroimaging studies and clinical trials may help clarify the nature of this relationship.

Topics: alpha-Synuclein; Cerebral Small Vessel Diseases; Cognitive Dysfunction; Humans; Hypotension, Orthostatic; Hypoxia-Ischemia, Brain; Lewy Body Disease; Longitudinal Studies; Magnetic Resonance Imaging; Mental Status Schedule; Multiple System Atrophy; Neuroglia; Parkinson Disease; Positron Emission Tomography Computed Tomography; Risk Factors; Statistics as Topic

Topics: alpha-Synuclein; Brain; Humans; Multiple Sclerosis; Multiple System Atrophy

Multiple system atrophy (MSA) is a predominantly sporadic, adult-onset, fatal neurodegenerative disease of unknown etiology. MSA is characterized by autonomic failure, levodopa-unresponsive parkinsonism, cerebellar ataxia and pyramidal signs in any combination. MSA belongs to a group of neurodegenerative disorders termed α-synucleinopathies, which also include Parkinson's disease and dementia with Lewy bodies. Their common pathological feature is the occurrence of abnormal α-synuclein positive inclusions in neurons or glial cells. In MSA, the main cell type presenting aggregates composed of α-synuclein are oligodendroglial cells . This pathological hallmark, also called glial cytoplasmic inclusions (GCIs) , is associated with progressive and profound neuronal loss in various regions of the brain. The development of animal models of MSA is justified by the limited understanding of the mechanisms of neurodegeneration and GCIs formation, which is paralleled by a lack of therapeutic strategies. Two main types of rodent models have been generated to replicate different features of MSA neuropathology. On one hand, neurotoxin-based models have been produced to reproduce neuronal loss in substantia nigra pars compacta and striatum. On the other hand, transgenic mouse models with overexpression of α-synuclein in oligodendroglia have been used to reproduce GCIs-related pathology. This chapter gives an overview of the atypical Parkinson's syndrome MSA and summarizes the currently available MSA animal models and their relevance for pre-clinical testing of disease-modifying therapies.

Topics: alpha-Synuclein; Animals; Disease Models, Animal; Humans; Multiple System Atrophy

Multiple system atrophy (MSA) is a sporadic, adult onset, relentlessly progressive neurodegenerative disease characterized by autonomic abnormalities associated with parkinsonism, cerebellar dysfunction, pyramidal signs, or combinations thereof. Treatments that can halt or reverse the progression of MSA have not yet been identified. MSA is neuropathologically defined by the presence of α-synuclein-containing inclusions, particularly in the cytoplasm of oligodendrocytes (glial cytoplasmic inclusions, GCIs), which are associated with neurodegeneration. The mechanisms by which oligodendrocytic α-synuclein inclusions cause neuronal death in MSA are not completely understood. The MSA neurodegenerative process likely comprises cell-to-cell transmission of α-synuclein in a prion-like manner, α-synuclein aggregation, increased oxidative stress, abnormal expression of tubulin proteins, decreased expression of neurotrophic factors, excitotoxicity and microglial activation, and neuroinflammation. In an attempt to block each of these pathogenic mechanisms, several pharmacologic approaches have been tried and shown to exert neuroprotective effects in transgenic mouse or cellular models of MSA. These include sertraline, paroxetine, and lithium, which hamper arrival of α-synuclein to oligodendroglia; rifampicin, lithium, and non-steroidal anti-inflammatory drugs, which inhibit α-synuclein aggregation in oligodendrocytes; riluzole, rasagiline, fluoxetine and mesenchymal stem cells, which exert neuroprotective actions; and minocycline and intravenous immunoglobulins, which reduce neuroinflammation and microglial activation. These and other potential therapeutic strategies for MSA are summarized in this review.

Topics: alpha-Synuclein; Animals; Anti-Inflammatory Agents; Disease Models, Animal; Disease Progression; Humans; Mice; Multiple System Atrophy; Neurodegenerative Diseases; Neuroprotective Agents; Oligodendroglia

Multiple system atrophy (MSA) is an α-synucleinopathy that is clinically characterized by varying degrees of parkinsonian, autonomic, and cerebellar features. Unlike other α-synucleinopathies such as Parkinson's disease, MSA is unique in that the principal α-synuclein lesions, called glial cytoplasmic inclusions, occur in oligodendroglia rather than neurons, with significantly more α-synuclein accumulating in MSA brain compared with Parkinson's disease. Although well defined clinically, the molecular pathophysiology of MSA has barely been investigated. In particular, there have been no systematic studies of the perturbation of the brain transcriptome during the onset and progression of this disease. Interestingly, measurements of α-synuclein gene (SNCA) expression in MSA brain tissue have not revealed overexpression of this gene in oligodendroglia or neurons. It has therefore become clear that other genes and gene networks, both directly as noncoding RNAs or through protein products, contribute to the accumulation of the α-synuclein protein in the brain. This review provides a summary of current developments in the investigation of the transcriptional causes of MSA and outlines perspectives for future research toward the elucidation of the molecular pathology of MSA-specific neurodegeneration.

Topics: alpha-Synuclein; Brain; Gene Expression; Humans; Multiple System Atrophy; Oligodendroglia; RNA, Messenger; RNA, Untranslated; Transcription, Genetic

Since their introduction in 1996, animal models of multiple system atrophy (MSA) have generated important insights into pathogenesis and interventional therapies. Toxin and genetic approaches have been used alone or in combination to replicate progressive motor and non-motor symptoms reflecting human neuropathology. Here, we review these developments and discuss the advantages and limitations of the MSA animal models, as well as their application in preclinical target validation.

Topics: alpha-Synuclein; Animals; Animals, Genetically Modified; Autonomic Nervous System; Biomarkers; Disease Models, Animal; Haplorhini; Mice; Multiple System Atrophy; Neurotoxins; Rats

Classically defined phenotypically by a triad of cerebellar ataxia, parkinsonism, and autonomic dysfunction in conjunction with pyramidal signs, multiple system atrophy (MSA) is a rare and progressive neurodegenerative disease affecting an estimated 3-4 per every 100,000 individuals among adults 50-99 years of age. With a pathological hallmark of alpha-synuclein-immunoreactive glial cytoplasmic inclusions (GCIs; Papp-Lantos inclusions), MSA patients exhibit marked neurodegenerative changes in the striatonigral and/or olivopontocerebellar structures of the brain. As a member of the alpha-synucleinopathy family, which is defined by its well-demarcated alpha-synuclein-immunoreactive inclusions and aggregation, MSA's clinical presentation exhibits several overlapping features with other members including Parkinson's disease (PD) and dementia with Lewy bodies (DLB). Given the extensive fund of knowledge regarding the genetic etiology of PD revealed within the past several years, a genetic investigation of MSA is warranted. While a current genome-wide association study is underway for MSA to further clarify the role of associated genetic loci and single-nucleotide polymorphisms, several cases have presented solid preliminary evidence of a genetic etiology. Naturally, genes and variants manifesting known associations with PD (and other phenotypically similar neurodegenerative disorders), including SNCA and MAPT, have been comprehensively investigated in MSA patient cohorts. More recently variants in COQ2 have been linked to MSA in the Japanese population although this finding awaits replication. Nonetheless, significant positive associations with subsequent independent replication studies have been scarce. With very limited information regarding genetic mutations or alterations in gene dosage as a cause of MSA, the search for novel risk genes, which may be in the form of common variants or rare variants, is the logical nexus for MSA research. We believe that the application of next generation genetic methods to MSA will provide valuable insight into the underlying causes of this disease, and will be central to the identification of etiologic-based therapies.

Topics: Alkyl and Aryl Transferases; alpha-Synuclein; Animals; Disease Models, Animal; Genetic Linkage; Genome-Wide Association Study; Humans; Lewy Body Disease; Multiple System Atrophy; Mutation; Parkinson Disease

The etiology and pathogenesis of neurodegenerative disorders has yet to be elucidated, so their differential diagnosis is a challenge. This is especially true in differentiating Alzheimer's disease (AD), dementia with Lewy bodies (DLB), Parkinson disease (PD), and multiple system atrophy (MSA).. A total of 11 eligible articles were identified by search of electronic databases including PubMed, Springer Link, Elsevier, and the Cochrane Library, up to June 2014. In meta-analyses, standardized mean differences (SMD), with 95% confidence intervals (CI), comparing cerebrospinal fluid (CSF) measures of α-synuclein between the above conditions were calculated using random-effects models.. CSF α-synuclein concentrations were significantly higher in AD compared to DLB [SMD: 0.32, 95% CI: (0.02, 0.62), z = 2.07, P = 0.038]; PD [SMD: 0.87, 95% CI: (0.15, 1.58), z = 2.38, P = 0.017]; or MSA [SMD: 1.14, 95% CI: (0.15, 2.14), z = 2.25, P = 0.025]. However, no significant difference was found between patients with AD and neurological cognitively normal controls [SMD: 0.02, 95% CI: (-0.21, 0.24), z = 0.13, P = 0.894].. Results of these meta-analysis suggest that quantification of CSF α-synuclein could help distinguish AD from other neurodegenerative disorders such as DLB, PD, or MSA.

Topics: alpha-Synuclein; Alzheimer Disease; Diagnosis, Differential; Humans; Lewy Body Disease; Multiple System Atrophy; Parkinson Disease

Despite growing research efforts, no reliable biomarker currently exists for the diagnosis and prognosis of multiple system atrophy (MSA). Such biomarkers are urgently needed to improve diagnostic accuracy, prognostic guidance and also to serve as efficacy measures or surrogates of target engagement for future clinical trials. We here review candidate fluid biomarkers for MSA and provide considerations for further developments and harmonization of standard operating procedures. A PubMed search was performed until April 24, 2015 to review the literature with regard to candidate blood and cerebrospinal fluid (CSF) biomarkers for MSA. Abstracts of 1760 studies were retrieved and screened for eligibility. The final list included 60 studies assessing fluid biomarkers in patients with MSA. Most studies have focused on alpha-synuclein, markers of axonal degeneration or catecholamines. Their results suggest that combining several CSF fluid biomarkers may be more successful than using single markers, at least for the diagnosis. Currently, the clinically most useful markers may comprise a combination of the light chain of neurofilament (which is consistently elevated in MSA compared to controls and Parkinson's disease), metabolites of the catecholamine pathway and proteins such as α-synuclein, DJ-1 and total-tau. Beyond future efforts in biomarker discovery, the harmonization of standard operating procedures will be crucial for future success.

Topics: alpha-Synuclein; Animals; Biomarkers; Brain; Catecholamines; Humans; Intermediate Filaments; Multiple System Atrophy; Nerve Degeneration

Topics: alpha-Synuclein; Animals; Female; Humans; Lewy Body Disease; Multiple System Atrophy; Parkinson Disease

Parkinson's disease (PD) and multiple system atrophy (MSA) are progressive neurodegenerative disorders classified as synucleinopathies, which are defined by the presence of α-synuclein protein pathology. Genetic studies have identified a total of 18 PARK loci that are associated with PD. The SNCA gene encodes the α-synuclein protein. The first pathogenic α-synuclein p.A53T substitution was discovered in 1997; this was followed by the identification of p.A30P and p.E46K pathogenic substitutions in 1998 and 2004, respectively. In the last year, two possible α-synuclein pathogenic substitutions, p.A18T and p.A29S, and two probable pathogenic substitutions, p.H50Q and p.G51D have been nominated. Next-generation sequencing approaches in familial PD have identified mutations in the VPS35 gene. A VPS35 p.D620N substitution remains the only confirmed pathogenic substitution. A second synucleinopathy, MSA, originally was considered a sporadic condition with little or no familial aggregation. However, recessive COQ2 mutations recently were nominated to be the genetic cause in a subset of familial and sporadic MSA cases. Further studies on the clinicogenetics and pathology of parkinsonian disorders will facilitate clarification of the molecular characteristics and pathomechanisms underlying these disorders.

Topics: Alkyl and Aryl Transferases; alpha-Synuclein; History, 20th Century; History, 21st Century; Humans; Multiple System Atrophy; Mutation; Parkinson Disease

α-Synucleinopathies are neurodegenerative diseases characterised by the abnormal accumulation of α-synuclein aggregates in neurons, nerve fibres or glial cells. While small amounts of these α-synuclein pathologies can occur in some neurologically normal individuals who do not have associated neurodegeneration, the absence of neurodegeneration in such individuals precludes them from having a degenerative α-synucleinopathy, and it has yet to be established whether such individuals have a form of preclinical disease. There are three main types of α-synucleinopathy, Parkinson's disease (PD), dementia with Lewy bodies (DLB), and multiple system atrophy (MSA), with other rare disorders also having α-synuclein pathologies, such as various neuroaxonal dystrophies. Multiple clinical phenotypes exist for each of the three main α-synucleinopathies, with these phenotypes differing in the dynamic distribution of their underlying neuropathologies. Identifying the factors involved in causing different α-synuclein phenotypes may ultimately lead to more targeted therapeutics as well as more accurate clinical prognosis.

Topics: alpha-Synuclein; Humans; Lewy Body Disease; Multiple System Atrophy; Parkinson Disease; Phenotype

Multiple system atrophy (MSA) is a fatal adult-onset neurodegenerative disorder of uncertain etiopathogenesis manifesting with autonomic failure, parkinsonism, and ataxia in any combination. The underlying neuropathology affects central autonomic, striatonigral and olivopontocerebellar pathways and it is associated with distinctive glial cytoplasmic inclusions (GCIs, Papp-Lantos bodies) that contain aggregates of α-synuclein. Current treatment options are very limited and mainly focused on symptomatic relief, whereas disease modifying options are lacking. Despite extensive testing, no neuroprotective drug treatment has been identified up to now; however, a neurorestorative approach utilizing autologous mesenchymal stem cells has shown remarkable beneficial effects in the cerebellar variant of MSA. Here, we review the progress made over the last decade in defining pathogenic targets in MSA and summarize insights gained from candidate disease-modifying interventions that have utilized a variety of well-established preclinical MSA models. We also discuss the current limitations that our field faces and suggest solutions for possible approaches in cause-directed therapies of MSA.

Topics: alpha-Synuclein; Animals; Biomarkers; Clinical Trials as Topic; Disease Models, Animal; Humans; Mitochondria; Multiple System Atrophy; Oxidative Stress

Multiple system atrophy (MSA) is a late-onset, sporadic neurodegenerative disorder clinically characterized by autonomic failure and either poorly levodopa-responsive parkinsonism or cerebellar ataxia. It is neuropathologically defined by widespread and abundant central nervous system α-synuclein-positive glial cytoplasmic inclusions and striatonigral and/or olivopontocerebellar neurodegeneration. There are two clinical subtypes of MSA distinguished by the predominant motor features: the parkinsonian variant (MSA-P) and the cerebellar variant (MSA-C). Despite recent progress in understanding the pathobiology of MSA, investigations into the symptomatology and natural history of the cerebellar variant of the disease have been limited. MSA-C presents a unique challenge to both clinicians and researchers alike. A key question is how to distinguish early in the disease course between MSA-C and other causes of adult-onset cerebellar ataxia. This is a particularly difficult question, because the clinical framework for conceptualizing and studying sporadic adult-onset ataxias continues to undergo flux. To date, several investigations have attempted to identify clinical features, imaging, and other biomarkers that may be predictive of MSA-C. This review presents a clinically oriented overview of our current understanding of MSA-C with a focus on evidence for distinguishing MSA-C from other sporadic, adult-onset ataxias.

Topics: alpha-Synuclein; Animals; Cerebellar Ataxia; Cerebellum; Disease Models, Animal; Humans; Multiple System Atrophy; Parkinsonian Disorders

Despite active fundamental, translational and clinical research, no therapeutic intervention has yet shown convincing effects on disease progression in Parkinson's disease (PD) patients. Indeed, several disease-modification trials failed or proved to be inconclusive due to lack of consistency between clinical rating scales and putative surrogate markers of disease progression, or confounding symptomatic effects of the tested compound. Multiple system atrophy (MSA) is a rapidly progressing orphan disorder leading to severe motor disability within a few years. Together with PD and dementia with Lewy bodies (DLB), MSA belongs to the synucleinopathies, a group of neurodegenerative disorders characterized by the abnormal accumulation of alpha-synuclein. Crucial milestones have been reached for successfully conducting clinical intervention trials in a large number of patients with MSA. In this personal view, we will review evidence, and discuss why MSA could prove the most relevant clinical model for assessing treatments that target mechanisms operating in all synucleinopathies.

Topics: alpha-Synuclein; Brain; Clinical Trials as Topic; Humans; Multiple System Atrophy; Parkinson Disease

There is evidence that the α-synucleinopathies Parkinson's disease (PD) and the Parkinson variant of multiple system atrophy (MSA-P) overlap at multiple levels. Both disorders are characterized by deposition of abnormally phosphorylated fibrillar α-synuclein within the central nervous system suggesting shared pathophysiological mechanisms. Despite the considerable clinical overlap in the early disease stages, MSA-P, in contrast to PD, is fatal and rapidly progressive. Moreover recent clinical studies have shown that surrogate markers of disease progression can be quantified easily and may reliably depict the rapid course of MSA. We therefore posit that, MSA-P may be exploited as a filter barrier in the development of disease-modifying therapeutic strategies targeting common pathophysiological mechanisms of α-synucleinopathies. This approach might reduce the number of negative phase III clinical trials, and, in turn, shift the available resources to earlier development stages, thereby increasing the number of candidate compounds validated.

Topics: alpha-Synuclein; Drug Discovery; Humans; Multiple System Atrophy; Parkinson Disease

Alpha-synuclein plays a key role in the pathology of synucleinopathies including Parkinson's disease (PD) and multiple system atrophy (MSA). However, whether alpha-synuclein level in cerebrospinal fluid (CSF) could distinguish synucleinopathies from progressive supranuclear palsy (PSP) is still a contentious issue. A comprehensive literature search yielded nine eligible studies. We expressed the between-group difference of the concentration of alpha-synuclein in CSF as the standardized mean difference. The proportion of variation attributable to heterogeneity was computed and expressed as I(2) . Nine studies involved 537 controls, 843 PD, 130 MSA, and 98 PSP patients. The overall effect of PD on alpha-synuclein in CSF was significantly different from normal control or disease control (standardized mean difference = -0.67, P < 0.00001). These studies were heterogeneous (I(2) = 40%). Alpha-synuclein in CSF in MSA was significantly reduced relative to controls with heterogeneous studies (standardized mean difference = -0.75, P < 0.0001; I(2) = 62%). In contrast, no significant difference of alpha-synuclein in CSF was observed between PSP and controls with heterogeneous studies (standardized mean difference = -0.28, P = 0.13; I(2) = 53%). Alpha-synuclein in CSF was significantly reduced in synucleinopathies compared with PSP ("PD vs. PSP": standardized mean difference = -0.38, P = 0.001; "MSA vs. PSP": standardized mean difference = -0.66, P < 0.00001). The included studies were homogeneous (I(2) = 0%). Our study showed that alpha-synuclein levels in CSF in synucleinopathies was significantly lower than in PSP. This finding provides insights into the pathophysiological difference between synucleinopathies and PSP as well as possibility of development of a tool for differential diagnosis between MSA and PSP using enzyme-linked immunosorbent assay (ELISA) and similar methods.

Topics: Aged; alpha-Synuclein; Female; Humans; Male; Middle Aged; Multiple System Atrophy; Parkinson Disease; Supranuclear Palsy, Progressive

Multiple system atrophy (MSA) is a fatal adult-onset neurodegenerative disorder of uncertain etiology, clinically manifesting with autonomic failure associated with parkinsonism, cerebellar dysfunction, and pyramidal signs in variable combination. The pathological process affects central autonomic, striatonigral, and olivopontocerebellar systems. These show varying degrees of neurodegeneration and underlie the stratification of the heterogenous disorder into MSA-P and MSA-C clinical variants, which correlate to the morphologic phenotypes of striatonigral degeneration and olivopontocerebellar atrophy (MSA-C). The lesions are not limited to these most consistently and severely affected systems but may involve many other parts of the central, peripheral, and autonomic nervous systems, underpinning the multisystem character of MSA. The histological core feature are glial cytoplasmic inclusions (GCIs, Papp-Lantos bodies) in all types of oligodendroglia that contain aggregates of misfolded α-Synuclein (α-Syn). In addition to the ectopic appearance of α-Syn in oligodendrocytes and other cells, oxidative stress, proteasomal and mitochondrial dysfunction, excitotoxiciy, neuroinflammation, metabolic changes, and energy failure are important contributors to the pathogenesis of MSA, as shown by various neurotoxic and transgenic animal models. Although the basic mechanisms of α-Syn-triggered neurodegeneration are not completely understood, neuron-to-oligodendrocyte transfer of α-Syn by prion-like spreading, inducing oligodendroglial and myelin dysfunction associated with chronic neuroinflammation, are suggested finally to lead to a system-specific pattern of neurodegeneration.

Topics: alpha-Synuclein; Animals; Humans; Multiple System Atrophy; Nervous System Diseases; Neurons; Oligodendroglia; Shy-Drager Syndrome

In 2013, European MSA Study Group demonstrated the prospective natural history of MSA. This study was greatly useful for better patients' management and future development of disease-modifying therapy. Although the diagnosis of early symptomatic stage is also an important factor for successful outcome of disease-modifying therapy, current diagnostic criteria for MSA, which has focused on the combination of motor and autonomic manifestations cannot diagnose MSA patients showing isolated autonomic failure in the early course of illness. We presented four premotor MSA patients who had sudden death prior to fulfilling the diagnostic criteria. 4 cases had very mild OPC and SN pathology, but significant autonomic system involvement including the intermediolateral nucleus, Onuf's nucleus, and medullary autonomic nucleus. Contrary, Petrovic et al reported four pathologically proven MSA patients with disease duration of 15 years or more. All patients presented isolated parkinsonism for a long time and mean duration from onset to dysautonomia was 9 years. Novel diagnostic biomarkers, which have a potential for evaluation of the component of glial cytoplasmic inclusion such as alpha-synuclein radiotracer and serum and CSF alpha-synuclein levels may be a key way to support the diagnosis of patients at the stage of "mono system atrophy".

Topics: alpha-Synuclein; Biomarkers; Death, Sudden; Ghrelin; Humans; Multiple System Atrophy; Parkinsonian Disorders; Time Factors

Progressive supranuclear palsy (PSP) is the most common atypical parkinsonian syndrome comprising two main clinical subtypes: Richardson's syndrome (RS), characterized by prominent postural instability, supranuclear vertical gaze palsy and frontal dysfunction; and PSP-parkinsonism (PSP-P) which is characterized by an asymmetric onset, tremor and moderate initial therapeutic response to levodopa. The early clinical features of PSP-P are often difficult to discern from idiopathic Parkinson's disease (PD), and other atypical parkinsonian disorders, including multiple system atrophy (MSA) and corticobasal syndrome (CBS). In addition, rare PSP subtypes may be overlooked or misdiagnosed if there are atypical features present. The differentiation between atypical parkinsonian disorders and PD is important because the prognoses are different, and there are different responses to therapy. Structural and functional imaging, although currently of limited diagnostic value for individual use in early disease, may contribute valuable information in the differential diagnosis of PSP. A growing body of evidence shows the importance of CSF biomarkers in distinguishing between atypical parkinsonian disorders particularly early in their course when disease-modifying therapies are becoming available. However, specific diagnostic CSF biomarkers have yet to be identified. In the absence of reliable disease-specific markers, we provide an update of the recent literature on the assessment of clinical symptoms, pathology, neuroimaging and biofluid markers that might help to distinguish between these overlapping conditions early in the course of the disease.

Topics: Age of Onset; alpha-Synuclein; Biomarkers; Brain; Gait Disorders, Neurologic; Humans; Imaging, Three-Dimensional; Magnetic Resonance Imaging; Multiple System Atrophy; Neuroimaging; Parkinsonian Disorders; Positron-Emission Tomography; Prognosis; Supranuclear Palsy, Progressive; Symptom Assessment; tau Proteins; Ultrasonography, Doppler, Transcranial

The pathogenesis of many neurodegenerative disorders arises in association with the misfolding and accumulation of a wide variety of proteins. Much emphasis has been placed on understanding the nature of these protein accumulations, including their composition, the process by which they are formed and the physiological impact they impose at cellular and, ultimately, organismal levels. Alpha-synuclein (ASYN) is the major component of protein inclusions known as Lewy bodies and Lewy neurites, which are the typical pathological hallmarks in disorders referred to as synucleinopathies. In addition, mutations or multiplications in the gene encoding for ASYN have also been shown to cause familial cases of PD, the most common synucleinopathy. Although the precise function of ASYN remains unclear, it appears to be involved in a vast array of cellular processes. Here, we review, in depth, a spectrum of cellular and molecular mechanisms that have been implicated in synucleinopathies. Importantly, detailed understanding of the biology/pathobiology of ASYN may enable the development of novel avenues for diagnosis and/or therapeutic intervention in synucleinopathies.

Topics: alpha-Synuclein; Animals; beta-Synuclein; Endoplasmic Reticulum; gamma-Synuclein; Humans; Lewy Bodies; Lewy Body Disease; Multiple System Atrophy; Parkinson Disease; Phosphorylation; Pure Autonomic Failure; Synaptic Transmission; Ubiquitinated Proteins; Ubiquitination

Cardiovascular autonomic failure is the second most common dysautonomic feature of α-synucleinopathies and has significant impact on daily activities and quality of life. Here we provide a systematic review of cardiovascular autonomic failure in α-synucleinopathies, emphasizing its impact on cognitive functions and disease outcomes. Articles spanning the period between January 1985 and April 2012 were identified from the PubMed database using a keyword-based search. Epidemiological studies highlight the negative prognostic effect of cardiovascular autonomic failure on cardiovascular and cerebrovascular outcomes and overall mortality in all α-synucleinopathies. Altered cerebral perfusion, vascular pressure stress, and related disruption of the blood-brain barrier may also contribute to the white matter hyperintensities and cognitive dysfunction frequently found in patients affected by neurocardiovascular instability. These findings support the hypothesis that cardiovascular autonomic failure may play a negative prognostic role in α-synucleinopathies and suggest that precocious screening and therapeutic management of cardiovascular autonomic failure may positively impact disease course.

Topics: alpha-Synuclein; Brain; Cardiovascular System; Cognition Disorders; Disease Progression; Fatigue; Humans; Hypotension, Orthostatic; Lewy Body Disease; Multiple System Atrophy; Neurodegenerative Diseases; Parkinson Disease; Primary Dysautonomias; Prognosis; Pure Autonomic Failure

Multiple system atrophy (MSA) is a sporadic adult-onset neurodegenerative disorder clinically characterized by a variable combination of dysautonomia, levodopa-unresponsive parkinsonian and cerebellar symptoms. Neurodegeneration in MSA occurs in the substantia nigra, putamen, inferior olive, pontine and brainstem nuclei, as well as intermediolateral cell column of the spinal cord. MSA is recognized as a synucleinopathy due to the accumulation of insoluble alpha-synuclein in oligodendroglial cytoplasmic inclusions. Several animal models have been developed in order to reproduce various clinical and pathological features of MSA. Using "double toxin-double lesion" or "single toxin-double lesion", neurotoxin-based models were designed in rats, mice and non-human primates to reproduce the neuropathology of MSA in the nigrostriatal system while gene-based models were developed in mice to reproduce the accumulation of insoluble alpha-synuclein in oligodendrocytes. Both approaches have then been merged to create optimized, dual-hit models. This review describes the different animal models of MSA, their respective advantages and limitations and their usefulness to decipher the pathophysiology of MSA then to define efficient symptomatic and disease-modifying therapies. This article is part of a Special Issue entitled: Neuroscience Disease Models.

Topics: alpha-Synuclein; Animals; Corpus Striatum; Disease Models, Animal; Multiple System Atrophy; Nerve Degeneration; Neurotoxins; Substantia Nigra

Multiple system atrophy (MSA) is an unrelenting, sporadic, adult-onset, neurodegenerative disease of unknown aetiology. Its clinically progressive course is characterized by a variable combination of parkinsonism, cerebellar ataxia and/or autonomic dysfunction. Neuropathological examination often reveals gross abnormalities of the striatonigral and/or olivopontocerebellar systems, which upon microscopic examination are associated with severe neuronal loss, gliosis, myelin pallor and axonal degeneration. MSA is a member of a diverse group of neurodegenerative disorders termed α-synucleinopathies, due to the presence of abnormal α-synuclein positive cytoplasmic inclusions in oligodendrocytes, termed glial cytoplasmic inclusions. These are the hallmark neuropathological lesion of MSA and are thought to play a central role in the pathogenesis of the disease. In this review, neuropathological features of MSA are described in detail, along with recent advances in the pathophysiology and genetics of the disease. Our current knowledge of the expression and accumulation of α-synuclein, and efforts to model the disease in vitro and in vivo, are emphasized in this paper and have helped formulate a working hypothesis for the pathogenesis of MSA.

Topics: alpha-Synuclein; Animals; Brain; Humans; Multiple System Atrophy

Atypical parkinsonian disorders (APDs) comprise a heterogenous group of disorders including multiple system atrophy (MSA), dementia with Lewy bodies (DLB), progressive supranuclear palsy (PSP) and corticobasal degeneration (CBD). Based on literature published in 2010, we here review recent advances in the APD field.. Genome-wide association studies have provided robust evidence of increased disease risk conferred by synuclein and tau gene variants in MSA and PSP. Furthermore, advanced imaging tools have been established in the differential diagnosis and as surrogate markers of disease activity in patients with APDs. Finally, although therapeutic options are still disappointing, translational research into disease-modifying strategies has accelerated with the increasing availability of transgenic animal models, particularly for MSA.. Remarkable progress has been achieved in the field of APDs, and advances in the genetics, molecular biology and neuroimaging of these disorders will continue to facilitate intensified clinical trial activity.

Topics: alpha-Synuclein; Animals; Animals, Genetically Modified; Clinical Trials as Topic; Diagnosis, Differential; Genome-Wide Association Study; Humans; Lewy Body Disease; Multiple System Atrophy; Parkinsonian Disorders; Supranuclear Palsy, Progressive; tau Proteins

Abnormal aggregates of the synaptic protein, α-synuclein, are the dominant pathology in syndromes known as the synucleinopathies. The cellular aggregation of the protein occurs in three distinct types of inclusions in three main clinical syndromes. α-Synuclein deposits in neuronal Lewy bodies and Lewy neurites in idiopathic Parkinson's disease (PD) and dementia with Lewy bodies (DLB), as well as incidentally in a number of other conditions. In contrast, α-synuclein deposits largely in oligodendroglial cytoplasmic inclusions in multiple system atrophy (MSA). Lastly, α-synuclein also deposits in large axonal spheroids in a number of rarer neuroaxonal dystrophies. Disorders are usually defined by their most dominant pathology, but for the synucleinopathies, clinical heterogeneity within the main syndromes is well documented. MSA was originally viewed as three different clinical phenotypes due to different anatomical localization of the lesions. In PD, recent meta-analyses have identified four main clinical phenotypes, and clinicopathological correlations suggest that more severe and more rapid progression of pathology with chronological age, as well as the involvement of additional neuropathologies, differentiates these phenotypes. In DLB, recent large studies show that clinical diagnosis is too insensitive to identify the syndrome itself, although clinicopathological studies suggest variable clinical features occur in the different pathological forms of this syndrome (pure DLB, DLB with Alzheimer's disease (AD), and AD with amygdala predominant Lewy pathology). The recognition of considerable heterogeneity within the synucleinopathy syndromes is important for the identification of factors involved in changing their pathological phenotype.

Topics: alpha-Synuclein; Alzheimer Disease; Brain; Humans; Lewy Body Disease; Multiple System Atrophy; Parkinson Disease

Multiple system atrophy (MSA) is a neurodegenerative disease involving motor abnormalities that include akinesia, rigidity and postural instability. While improved diagnostic criteria have aided the accurate diagnosis of MSA, our understanding of the neuropathological aspects underlying MSA was bolstered by the identification of α-synuclein (α-syn) as the primary constituent of the abnormal protein aggregates observed in the brains of MSA patients. The generation of transgenic animal models of MSA coupled with an increasing understanding of the biochemical structure and function of α-syn has highlighted a number of key pathological pathways thought to underlie the neurodegeneration observed in MSA. This review summarizes key findings in the field, discusses current areas of debate, and describes current experimental approaches towards disease-modifying therapies.

Topics: alpha-Synuclein; Animals; Animals, Genetically Modified; Brain; Disease Models, Animal; Humans; Multiple System Atrophy; Oligodendroglia

Topics: Adult; Aged; Aged, 80 and over; alpha-Synuclein; Female; Glucosylceramidase; Humans; Middle Aged; Multiple System Atrophy; Mutation; Neurons; Signal Transduction

Multiple system atrophy (MSA) is a rare late onset neurodegenerative disorder which presents with autonomic failure and a complicated motor syndrome including atypical parkinsonism, ataxia and pyramidal signs. MSA is a glial alpha-synucleinopathy with rapid progression and currently poor therapeutic management. This paper reviews the clinical features, natural history and novel diagnostic criteria for MSA as well as contemporary knowledge on pathogenesis based on evidence from neuropathological studies and experimental models. An outline of the rationale for managing symptomatic deterioration in MSA is provided together with a summary of novel experimental therapeutic approaches to decrease disease progression.

Topics: alpha-Synuclein; Animals; Disease Progression; Humans; Multiple System Atrophy; Neurodegenerative Diseases; Shy-Drager Syndrome

Multiple system atrophy (MSA) is a sporadic neurodegenerative disorder that encompasses olivopontocerebellar atrophy (OPCA), striatonigral degeneration (SND) and Shy-Drager syndrome (SDS). The histopathological hallmarks are alpha-synuclein (AS) positive glial cytoplasmic inclusions (GCIs) in oligodendroglias. AS aggregation is also found in glial nuclear inclusions (GNIs), neuronal cytoplasmic inclusions (NCIs), neuronal nuclear inclusions (NNIs) and dystrophic neurites. Reviewing the pathological features in 102 MSA cases revealed that the, OPCA-type was relatively more frequent and SND-type was less frequent in Japanese MSA cases. The frequency of the SND-type is relatively high in Western countries. This different in the dominant type suggests that the phenotypic patterns of MSA may vary with the race. In early stages of MSA, in addition to GCIs, NNIs, NCIs, and diffuse homogenous stain of AS in neuronal nuclei and cytoplasm were observed in various vulnerable lesions including the pontine nuclei, putamen, substantia nigra, locus ceruleus, inferior olivary nucleus, intermediolateral column of the thoracic cord, lower motor neurons, and cortical pyramidal neurons. These findings indicated that the primary nonfibrillar and fibrillar AS aggregation also occurred in neurons. Therefore, both the direct involvement of neurons themselves and the oligodendroglia-myelin-axon mechanism may synergistically accelerate the degenerative process of MSA.

Topics: alpha-Synuclein; Humans; Inclusion Bodies; Multiple System Atrophy; Nerve Degeneration; Oligodendroglia

Multiple system atrophy (MSA) is a sporadic and rapidly progressive neurodegenerative disorder that presents with autonomic failure in combination with parkinsonism or cerebellar ataxia. Over the past 5 years, substantial progress has been achieved in understanding the pathogenesis of the disease. Important insights into the epidemiology and genetics of MSA have confirmed the key pathogenic role of alpha-synuclein. Advances in the early recognition of this disease have resulted in revised diagnostic criteria, including, for the first time, neuroimaging indices. Finally, novel therapeutic options targeting disease modification have been investigated in clinical trials. These include riluzole, recombinant human growth hormone, and minocycline. Although the trials did not find any positive effects on disease progression, they generated important trial expertise in MSA and were only possible because of the establishment of international networks.

Topics: alpha-Synuclein; Excitatory Amino Acid Antagonists; Humans; Multiple System Atrophy; Prognosis; Riluzole

To this day, the cause of multiple system atrophy (MSA) remains stubbornly enigmatic. A growing body of observations regarding the clinical, morphological, and biochemical phenotypes of MSA has been published, but the interested student is still left without a clue as to its underlying cause. MSA has long been considered a rare cousin of Parkinson's disease and cerebellar degeneration; it is rich in acronyms but poor in genetic and environmental leads. Because of the worldwide research efforts conducted over the last two decades and the discovery of the alpha-synuclein-encoding SNCA gene as a cause of rare familial Parkinson's disease, the MSA field has seen advances on three fronts: the identification of its principal cellular target, that is, oligodendrocytes; the characterization of alpha-synuclein-rich glial cytoplasmic inclusions as a suitable marker at autopsy; and improved diagnostic accuracy in living patients resulting from detailed clinicopathological studies. The working model of MSA as a primary glial disorder was recently strengthened by the finding of dysregulation in the metabolism of myelin basic protein and p25alpha, a central nervous system-specific phosphoprotein (also called tubulin polymerization promoting protein, TPPP). Intriguingly, in early cases of MSA, the oligodendrocytic changes in myelin basic protein and p25alpha processing were recorded even before formation of glial cytoplasmic inclusions became detectable. Here, we review the evolving concept that MSA may not just be related to Parkinson's disease but also share traits with the family of demyelinating disorders. Although these syndromes vary in their respective cause of oligodendrogliopathy, they have in common myelin disruption that is often followed by axonal dysfunction.

Topics: alpha-Synuclein; Animals; Biomarkers; Brain; Humans; Inclusion Bodies; Multiple System Atrophy; Myelin Basic Protein; Nerve Fibers, Myelinated; Nerve Tissue Proteins; Oligodendroglia

Neurodegenerative disorders of the aging population affect over 5 million people in the US and Europe alone. The common feature is the progressive accumulation of misfolded proteins with the formation of toxic oligomers. Previous studies show that while in Alzheimer's disease (AD) misfolded amyloid-beta protein accumulates both in the intracellular and extracellular space, in Lewy body disease (LBD), Parkinson's disease (PD), Multiple System Atrophy (MSA), Fronto-Temporal dementia (FTD), prion diseases, amyotrophic lateral sclerosis (ALS) and trinucleotide repeat disorders (TNRD), the aggregated proteins accumulate in the plasma membrane and intracellularly. Protein misfolding and accumulation is the result of an altered balance between protein synthesis, aggregation rate and clearance. Based on these studies, considerable advances have been made in the past years in developing novel experimental models of neurodegenerative disorders. This has been in part driven by the identification of genetic mutations associated with familial forms of these conditions and gene polymorphisms associated with the more common sporadic variants of these diseases. Transgenic and knock out rodents and Drosophila as well as viral vector driven models of Alzheimer's disease (AD), PD, Huntington's disease (HD) and others have been developed, however the focus for this review will be on rodent models of AD, FTD, PD/LBD, and MSA. Promising therapeutic results have been obtained utilizing amyloid precursor protein (APP) transgenic (tg) models of AD to develop therapies including use of inhibitors of the APP-processing enzymes beta- and gamma-secretase as well as vaccine therapies.

Topics: alpha-Synuclein; Alzheimer Disease; Amyloid beta-Protein Precursor; Animals; Animals, Genetically Modified; Disease Models, Animal; Humans; Lewy Body Disease; Multiple System Atrophy; Neurodegenerative Diseases; Parkinson Disease; tau Proteins

Multiple system atrophy (MSA) is a sporadic neurodegenerative disorder that encompasses olivopontocerebellar atrophy (OPCA), striatonigral degeneration (SND) and Shy-Drager syndrome (SDS). The histopathological hallmark is the formation of alpha-synuclein-positive glial cytoplasmic inclusions (GCIs) in oligodendroglia. alpha-synuclein aggregation is also found in glial nuclear inclusions, neuronal cytoplasmic inclusions (NCIs), neuronal nuclear inclusions (NNIs) and dystrophic neurites. We evaluated the pathological features of 102 MSA cases, and presented the pathological spectrum of MSA and initial features of alpha-synuclein accumulation. We found that 39% of the 102 cases showed equivalent SND and OPCA pathologies, 33% showed OPCA- and 22% showed SND-predominant pathology, whereas 6% showed extremely mild changes. Our pathological analysis indicated that OPCA-type was relatively more frequent and SND-type was less frequent in Japanese MSA cases, compared to the relatively high frequency of SND-type in Western countries, suggesting that different phenotypic patterns of MSA may exist between races. In the early stage, in addition to GCIs, NNIs and diffuse homogenous alpha-synuclein staining in neuronal nuclei and cytoplasm were observed in lesions in the pontine nuclei, putamen, substantia nigra, locus ceruleus, inferior olivary nucleus, intermediolateral column of thoracic spinal cord, lower motor neurons and cortical pyramidal neurons. A subgroup of MSA cases with severe temporal atrophy showed numerous NCIs, particularly in the limbic system. These findings suggest that primary non-fibrillar and fibrillar alpha-synuclein aggregation also occur in neurons. The oligo-myelin-axon-neuron complex mechanism, along with the direct involvement of neurons themselves, may synergistically accelerate the degenerative process of MSA.

Topics: alpha-Synuclein; Autonomic Nervous System; Biomarkers; Brain; Cerebral Cortex; Humans; Motor Neurons; Multiple System Atrophy; Nerve Degeneration; Neurons

Progressive supranuclear palsy (PSP) is a neurodegenerative tauopathy characterized by Parkinsonism, vertical gaze palsy, and early falls. The neuropathology is characterized by neurofibrillary tangles, tufted astrocytes, and coiled bodies, but some brains show other pathologic processes. To investigate the frequency of alpha-synuclein pathology in PSP with immunohistochemistry and to report the clinical and pathological features of a case of PSP with concomitant Multiple system atrophy (MSA) (PSP/MSA), 290 cases of PSP were screened for alpha-synuclein pathology with immunohistochemistry. Double-labeling immunohistochemistry was performed on a case of PSP/MSA. Among the PSP cases screened for alpha-synuclein pathology, a single case of PSP/MSA was detected. The patient was an 86-year-old woman with clinical features consistent with PSP. She had no documented dysautonomia or cerebellar signs, and imaging studies were not diagnostic of MSA. Pathological examination showed tau-immunoreactive neuronal and glial lesions consistent with PSP as well as alpha-synuclein immunoreactive glial cytoplasmic inclusions diagnostic of MSA. Double-immunolabeling studies showed no co-localization of alpha-synuclein and tau in most neuronal and glial lesions. Based upon the findings in this case, the neuropathologic changes of PSP and MSA are distinct and independent processes, but they can occasionally coexist.

Topics: Aged, 80 and over; alpha-Synuclein; Brain; Female; Humans; Immunohistochemistry; Inclusion Bodies; Multiple System Atrophy; Neurofibrillary Tangles; Supranuclear Palsy, Progressive; tau Proteins; Tissue Distribution

Multiple system atrophy (MSA) is a sporadic, adult-onset neurodegenerative disease, which is characterized by striatonigral degeneration, olivopontocerebellar atrophy, and preganglionic autonomic lesions in any combination. The histological hallmark is the presence of argyrophilic fibrillary inclusions in the oligodendrocytes, referred to as glial cytoplasmic inclusions (GCIs). Fibrillary inclusions are also found in the neuronal somata, axons, and nucleus. Neuronal cytoplasmic inclusions are frequently found in the pontine and inferior olivary nuclei. Since the discovery of alpha-synuclein as a major component of glial and neuronal inclusions in MSA, two neurodegenerative processes have been considered in this disease: one is due to the widespread occurrence of GCIs associated with oligodendroglia-myelin degeneration (oligodendrogliopathy) in the central nervous system, and the other is due to the filamentous aggregation of alpha-synuclein in the neurons in several brain regions. These two degenerative processes might synergistically cause neuronal depletion in MSA.

Topics: alpha-Synuclein; Animals; Brain; Humans; Immunohistochemistry; Inclusion Bodies; Multiple System Atrophy; Nerve Degeneration; Neuroglia; Neurons

The discovery of glial cytoplasmic inclusions (GCIs) in 1989 helped to define multiple system atrophy (MSA) as a clinicopathological entity, and drew attention to the prominent role played by these inclusions in the pathogenesis of the disorder. Subsequently, GCIs were shown to be highly positive for alpha-synuclein, a neuronal protein that is normally absent in oligodendroglia except during embryonic development. The source of oligodendroglial alpha-synuclein aggregation in MSA is unknown. Since genetic overexpression has been excluded, active uptake from dying neurons remains a possibility. The similar topography of oligodendroglial and neuronal pathology in MSA suggests a fundamental disturbance of the functional unit between oligodendroglia, axon, and neuron. Transgenic MSA mouse models are now available to determine these aspects of cellular disturbance experimentally.

Topics: alpha-Synuclein; Animals; Animals, Genetically Modified; Brain; Humans; Inclusion Bodies; Models, Neurological; Multiple System Atrophy; Nerve Tissue Proteins; Neuroglia; Neurons; Synucleins

Synucleins are a family of small, highly charged proteins expressed predominantly in neurons. Since their discovery and characterization during the last decade, much has been learned about their structure, potential functions, interactions with other proteins, and roles in disease. One of these proteins, alpha-synuclein (alpha-syn), is the major building block of pathological inclusions that characterize many neurodegenerative disorders, including Parkinson's disease (PD), dementia with Lewy bodies (DLB), and neurodegeneration with brain iron accumulation type 1 (NBIA-1), which collectively are termed synucleinopathies. Furthermore, genetic and biological studies support a role for alpha-syn in the pathophysiology of these diseases. Therefore, research must be continued in order to better understand the functions of the synuclein proteins under normal physiological conditions as well as their role in diseases.

Topics: alpha-Synuclein; Amino Acid Sequence; Animals; Animals, Genetically Modified; Dementia; Humans; Lewy Bodies; Models, Biological; Models, Chemical; Molecular Sequence Data; Multiple System Atrophy; Nerve Tissue Proteins; Neurodegenerative Diseases; Nitrogen; Oxygen; Parkinson Disease; Pesticides; Protein Binding; Sequence Homology, Amino Acid; Synucleins

The understanding of the molecular mechanisms underlying Parkinson's disease, progressive supranuclear palsy, and multiple system atrophy has made significant progress in the recent years. Lewy body appears to be principally made of alpha-synuclein, a presynaptic protein. It also contains ubiquitin and some components of the proteasome: this suggests that alteration of protein catabolism may be involved in its formation. In favor of this hypothesis, it should be noted that Parkin, a protein that is mutated in autosomal recessive Parkinson disease, is a ubiquitin ligase. Immunohistochemistry has shown that alpha-synuclein accumulates not only in the cell body of the neurones (Lewy body) but also in their processes (Lewy neurites); it has emphasized the severity of the pathology in the nucleus basalis of Meynert, amygdala, CA2-3 sector of the hippocampus and cerebral cortex. Cortical Lewy bodies are not considered any more the marker of dementia with Lewy bodies: they are, indeed, found in true Parkinson disease cases. In progressive supranuclear palsy, 4 repeats tau accumulates in the cytoplasm of neurones and glia. At electron microscopy, the accumulation is made of straight filaments. It involves not only the neurones (where it is the main constituent of the neurofibrillary tangles) but also the glia. Astrocytic tuft is to day considered the morphological marker of progressive supranuclear palsy. Tau protein accumulates in the cell body of the oligodendrocyte as a "coiled body"; the protein is also integrated in the myelin sheath, when the cytoplasm of the oligodendrocyte wraps around the axon. This explains the numerous "threads" that are visible in cases of progressive supranuclear palsy. Striato-nigral degeneration, sporadic olivo-ponto-cerebellar atrophy and primitive orthostatic hypotension are various clinico-pathologic aspects of the same disorder: multiple system atrophy. It is also characterized by a morphological marker: the accumulation of alpha-synuclein in the cytoplasm of glial cells, particularly oligodendrocytes. The term synucleinopathy has been proposed to describe both idiopathic Parkinson disease and multiple system atrophy. The reason explaining the cellular topography of alpha-synuclein accumulation, neuronal in Parkinson disease, glial in multiple system atrophy is still unknown.

Topics: alpha-Synuclein; Amygdala; Axons; Cerebral Cortex; Corpus Striatum; Cysteine Endopeptidases; Hippocampus; Humans; Hypotension, Orthostatic; Immunohistochemistry; Lewy Bodies; Ligases; Multienzyme Complexes; Multiple System Atrophy; Myelin Sheath; Nerve Tissue Proteins; Neuroglia; Oligodendroglia; Olivopontocerebellar Atrophies; Parkinsonian Disorders; Presynaptic Terminals; Proteasome Endopeptidase Complex; Supranuclear Palsy, Progressive; Synucleins; tau Proteins; Ubiquitin; Ubiquitin-Protein Ligases

Topics: alpha-Synuclein; Autonomic Nervous System Diseases; Circadian Rhythm; Humans; Inappropriate ADH Syndrome; Inclusion Bodies; Multiple System Atrophy; Nerve Tissue Proteins; Oligodendroglia; Polyuria; Protein Processing, Post-Translational; Suprachiasmatic Nucleus; Synucleins

The synucleinopathies are a diverse group of neurodegenerative disorders that share a common pathologic lesion composed of aggregates of insoluble alpha-synuclein protein in selectively vulnerable populations of neurons and glia. Growing evidence links the formation of abnormal filamentous aggregates to the onset and progression of clinical symptoms and the degeneration of affected brain regions in neurodegenerative disorders. These disorders may share an enigmatic symmetry, i.e., missense mutations in the gene encoding for the disease protein (alpha-synuclein) cause familial variants of Parkinson disease as well as its hallmark brain lesions, but the same brain lesions also form from the corresponding wild-type brain protein in the more common sporadic varieties of Parkinson disease. It is likely that clarification of this enigmatic symmetry in 1 form of synucleinopathy will have a profound impact on understanding the mechanisms underlying all these disorders. Furthermore, these efforts will likely lead to novel diagnostic and therapeutic strategies in regard to the synucleinopathies.

Topics: alpha-Synuclein; Animals; Humans; Lewy Body Disease; Multiple System Atrophy; Nerve Tissue Proteins; Neurodegenerative Diseases; Parkinson Disease; Synucleins

The term alpha-synucleinopathy is used to name a group of disorders having in common the abnormal deposition of alpha-synuclein in the cytoplasm of neurons or glial cells, as well as in extracellular deposits of amyloid. In Parkinson's disease and Lewy body dementia, alpha-synuclein is the main component of Lewy bodies and dystrophic neurites; alpha-synuclein also accumulates in the cytoplasm of glial cells. In multiple system atrophy, alpha-synuclein conforms the cytoplasmic oligodendroglial inclusions and the neuronal inclusions which are the hallmark of this disease. Finally, the amyloidogenic fragment 61-95 amino acids of alpha-synuclein is the non-Abeta component of senile plaque amyloid in Alzheimer disease. Accumulations of alpha-synuclein in all these disorders have in common a fibrilar configuration, but they differ in the binding of alpha-synuclein to distinct proteins with the exception of ubiquitin whose binding to alpha-synuclein is common to all alpha-synuclein inclusions. The mechanisms leading to alpha-synuclein fragmentation and aggegation into extracellular amyloid are not known, although alpha-synuclein fragment and betaA4 aggregates are the result of abnormal cleavage of large precursors. On the other hand, several studies have shown that alpha-synuclein may adopt a fibrilar conformation and give rise to insoluble forms and high molecular weight aggregates in vitro. Similar complexes have also been observed in alpha-synucleinopathies. Although studies in vitro and in vivo have shown toxic effects of alpha-synuclein, the consequence of alpha-synuclein deposition on cell survival in alpha-synucleinopathies is not known.

Topics: alpha-Synuclein; Alzheimer Disease; Cell Death; Cytoplasm; Humans; Lewy Body Disease; Multiple System Atrophy; Nerve Tissue Proteins; Neurodegenerative Diseases; Neuroglia; Neurons; Parkinson Disease; Synucleins

Topics: alpha-Synuclein; Animals; Disease Models, Animal; Dopamine; Humans; Lewy Bodies; Lewy Body Disease; Multigene Family; Multiple System Atrophy; Nerve Tissue Proteins; Neurodegenerative Diseases; Oxidative Stress; Parkinson Disease; Sequence Homology, Amino Acid; Synucleins

Multiple system atrophy is an adult onset neurodegenerative disease, featuring parkinsonism, ataxia, and autonomic failure, in any combination. The condition is relentlessly progressive and responds poorly to treatment. Death occurs on average six to seven years after the onset of symptoms. No familial cases of multiple system atrophy have been reported, and no environmental factors have been robustly implicated as aetiological factors. However, analytical epidemiological studies are hampered because the condition is relatively rare. The discovery of the glial cytoplasmic inclusion (GCI) in 1989 helped to define multiple system atrophy as a clinicopathological entity, and drew attention to the prominent, if not primary, role played by the oligodendrocyte in the pathogenesis of the condition. Subsequently, GCIs were shown to be positive for alpha-synuclein, with immunostaining for this protein indicating that white matter pathology was more widespread than had previously been recognised. The presence of alpha-synuclein in GCIs provides a link with Parkinson's disease, dementia with Lewy bodies, and neurodegeneration with brain iron accumulation, type 1 (or Hallervorden-Spatz syndrome), in which alpha-synuclein is also found within Lewy bodies. This has led to the term "synucleinopathy" to embrace this group of conditions. The GCIs of multiple system atrophy contain a range of other cytoskeletal proteins. It is unknown how fibrillogenesis occurs, and whether there is primary oligodendrocytic dysfunction, which then disrupts the neurone/axon as a consequence of the glial pathology, or whether the oligodendrocytic changes merely represent an epiphenomenon. Further research into this devastating condition is urgently needed to improve our understanding of the pathogenesis, and also to produce new treatment approaches.

Topics: Aged; alpha-Synuclein; Autonomic Nervous System; Axons; Brain; Brain-Derived Neurotrophic Factor; Cell Death; Extracellular Matrix; Female; Humans; Inclusion Bodies; Male; Middle Aged; Multiple System Atrophy; Nerve Tissue Proteins; Neurons; Oligodendroglia; Polymorphism, Genetic; Synucleins

Recently, mutations of the alpha-synuclein gene were found to cause dominantly inherited Lewy-body Parkinson's disease (PD) and alpha-synuclein was identified as a major component of the Lewy body. However, the cause of the common form of PD, with a multifactorial rather than autosomal dominant inheritance pattern, remains unknown. Alpha-synuclein precipitates slowly and apparently spontaneously at high concentration in solution and the mutations that cause PD accelerate precipitation. Other dominantly inherited late-onset or adult-onset dominantly inherited neurodegenerative diseases are associated with precipitation of proteins. In Alzheimer disease, beta-amyloid and tau abnormalities are present and in prion disorders, prion proteins are found. In Huntington disease, a disorder with expanded CAG repeats, huntingtin precipitates occur. In dominantly inherited spinocerebellar ataxias, also expanded CAG repeat disorders, the corresponding ataxin protein precipitates are found. In multiple system atrophy, alpha-synuclein precipitates are encountered and in progressive supranuclear palsy, tau precipitates occur. In familial amyotrophic lateral sclerosis, a group of dominantly inherited disorders, SOD1 precipitates are found. Most of these disorders can involve the basal ganglia in some way. Since similar processes seem to affect neurons of adults or older individuals and since a relatively limited group of proteins seems to be involved, each producing a form of neurodegeneration, it is possible that certain common features are present that affect this group of proteins. Candidates include a conformational shift, as in prions, an abnormality of the ubiquitin-proteosome pathway, as seen in PD, an abnormality of a pathway preventing precipitation (e.g. chaperonins), or potentiation of a pathway promoting precipitation (e.g. gamma-glutamyl-transpeptidase) or apoptosis. Elucidation of the pathways causing this protein insolubilisation is the first step towards approaching prevention and reversal in these late-onset neurodegenerative diseases.

Topics: Adult; Aged; alpha-Synuclein; Alzheimer Disease; Amyloid; Basal Ganglia; Chemical Precipitation; Down Syndrome; Heredodegenerative Disorders, Nervous System; Humans; Middle Aged; Multiple System Atrophy; Mutation; Nerve Tissue Proteins; Parkinson Disease; Solubility; Synucleins; tau Proteins

Multiple system atrophy is a sporadic, adult-onset neurodegenerative disease of unknown etiology. The condition may be unique among neurodegenerative diseases by the prominent, if not primary, role played by the oligodendroglial cell in the pathogenetic process. Recent developments in our understanding of multiple system atrophy have included the detection of glial cytoplasmic inclusions and alpha-synuclein accumulation in these inclusions. The latter finding links multiple system atrophy as an "alpha-synucleinopathy" to Parkinson's disease and dementia with Lewy bodies. This article reviews recent important findings of potential relevance to the pathogenesis of multiple system atrophy. We also speculate on areas in which further advances may be made to progress our understanding of this devastating condition.

Topics: alpha-Synuclein; Biomarkers; Brain; Gene Expression Regulation; Genes, Regulator; Humans; Inclusion Bodies; Multiple System Atrophy; Mutation; Nerve Tissue Proteins; Neuregulins; Oligodendroglia; Polymorphism, Genetic; Synucleins; tau Proteins

Parkinson's disease is the second most common neurodegenerative disease, after Alzheimer's disease. Neuropathologically, it is characterized by the degeneration of populations of nerve cells that develop filamentous inclusions in the form of Lewy bodies and Lewy neurites. Recent work has shown that the filamentous inclusions of Parkinson's disease are made of the protein alpha-synuclein and that rare, familial forms of Parkinson's disease are caused by missense mutations in the alpha-synuclein gene. Besides Parkinson's disease, the filamentous inclusions of two additional neurodegenerative diseases, namely, dementia with Lewy bodies and multiple system atrophy, have also been found to be made of alpha-synuclein. Recombinant alpha-synuclein has been shown to assemble into filaments with similar morphologies to those found in the human diseases and with a cross-beta fiber diffraction pattern. The new work has established the alpha-synucleinopathies as a major class of neurodegenerative disease.

Topics: alpha-Synuclein; Brain; Humans; Lewy Bodies; Lewy Body Disease; Multiple System Atrophy; Mutation, Missense; Nerve Tissue Proteins; Parkinson Disease; Synucleins

Parkinson's disease (PD), dementia with Lewy bodies (DLB) and multiple system atrophy (MSA) are increasingly recognized as alpha-synucleinopathies, i.e. neurodegenerative disorders that share a common subcellular pathology characterized by alpha-synuclein abnormal aggregation. In the present review we focus on depression in alpha-synucleinopathies, discussing epidemiological, pathophysiological and treatment aspects of this frequently disabling clinical feature which may occur in PD, DLB and MSA alike.

Topics: alpha-Synuclein; Animals; Antidepressive Agents; Brain; Depressive Disorder; Diagnosis, Differential; Humans; Lewy Body Disease; Multiple System Atrophy; Nerve Tissue Proteins; Parkinson Disease; Prevalence; Synucleins

The involvement of alpha-synuclein in neurodegenerative diseases was first suspected after the isolation of an alpha-synuclein fragment (NAC) from amyloid plaques in Alzheimer's disease (AD). Later, two different alpha-synuclein mutations were shown to be associated with autosomal-dominant Parkinson's disease (PD), but only in a small number of families. However, the discovery that alpha-synuclein is a major component of Lewy bodies and Lewy neurites, the pathological hallmarks of PD, confirmed its role in PD pathogenesis. Pathological aggregation of the protein might be responsible for neurodegeneration. In addition, soluble oligomers of alpha-synuclein might be even more toxic than the insoluble fibrils found in Lewy bodies. Multiple factors have been shown to accelerate alpha-synuclein aggregation in vitro. Therapeutic strategies aimed to prevent this aggregation are therefore envisaged. Although little has been learned about its normal function, alpha-synuclein appears to interact with a variety of proteins and membrane phospholipids, and may therefore participate in a number of signaling pathways. In particular, it may play a role in regulating cell differentiation, synaptic plasticity, cell survival, and dopaminergic neurotransmission. Thus, pathological mechanisms based on disrupted normal function are also possible.

Topics: 14-3-3 Proteins; alpha-Synuclein; Alzheimer Disease; Amyotrophic Lateral Sclerosis; Animals; Carrier Proteins; Cell Differentiation; Cell Survival; Dopamine; Humans; Molecular Chaperones; Multiple System Atrophy; Nerve Tissue Proteins; Neuronal Plasticity; Neurons; Parkinson Disease; Protein Structure, Tertiary; Synucleins; tau Proteins; Tyrosine 3-Monooxygenase

Despite being considered the archetypal non-genetic neurological disorder, genetic analysis of Parkinson's disease has shown that there are at least three genetic loci. Furthermore, these analyses have suggested that the phenotype of the pathogenic loci is wider than simple Parkinson's disease and may include Lewy body dementia and some forms of essential tremor. Identification of alpha-synuclein as the first of the loci involved in Parkinson's disease and the identification of this protein in pathological deposits in other disorders has led to the suggestion that it may share pathogenic mechanisms with multiple system atrophy, Alzheimer's disease and prion disease and that these mechanisms are related to a synuclein pathway to cell death. Finally, genetic analysis of the synuclein diseases and the tau diseases may indicate that this synuclein pathway is an alternative to the tau pathway to cell death.

Topics: alpha-Synuclein; Alzheimer Disease; Humans; Multiple System Atrophy; Nerve Tissue Proteins; Parkinsonian Disorders; Supranuclear Palsy, Progressive; Synucleins; tau Proteins

Multiple system atrophy (MSA) is a sporadic neurodegenerative disease characterized clinically by varying degrees of Parkinsonism, cerebellar ataxia and autonomic dysfunction and pathologically by degeneration in the substantia nigra, putamen, olivary nucleus, pontine nuclei and cerebellum. In addition to selective neuronal loss, iron pigment accumulation and gliosis, myelin pathology is increasingly recognized. In affected white matter, myelin displays signs of degeneration and oligodendroglia contain argyrophilic inclusion bodies, so-called glial cytoplasmic inclusions (GCI). GCI are composed of 10-15-nm diameter coated filaments that are immunoreactive for ubiquitin and alpha-synuclein. Similar inclusions are occasionally found in neuronal cell bodies and cell processes in MSA. Given the presence of inclusion bodies composed of synuclein, it is reasonable to assume that biochemical alterations would be detected in synuclein in MSA and indeed this is the case. In MSA synuclein has biophysical properties that suggest increasing insolubility such as sedimentation in dense fractions in sucrose gradients and ready extraction into detergents and formic acid. Surprisingly, these biochemical modifications in synuclein are more widespread in the brain that the obvious pathology and suggest a fundamental molecular characteristic of the disorder. Similar neuronal, and less frequently glial, inclusions are detected in Lewy body disease, where there is also evidence for biophysical alterations in synuclein. Thus, MSA and LBD are both synucleinopathies, and they may comprise different poles of a disease spectrum that includes sporadic disorders as well as genetically determined disorders such as familial Lewy body Parkinsonism.

Topics: alpha-Synuclein; Humans; Multiple System Atrophy; Nerve Tissue Proteins; Synucleins

Topics: alpha-Synuclein; Amyotrophic Lateral Sclerosis; Animals; Cysteine Endopeptidases; Humans; Lewy Bodies; Multienzyme Complexes; Multiple System Atrophy; Nerve Tissue Proteins; Neurodegenerative Diseases; Neurons; Parkinson Disease; Proteasome Endopeptidase Complex; Synucleins; Ubiquitins

Multiple system atrophy (MSA) is a fatal neurodegenerative disease characterized by the aggregation of α-synuclein in glia and neurons. Sirolimus (rapamycin) is an mTOR inhibitor that promotes α-synuclein autophagy and reduces its associated neurotoxicity in preclinical models.. To investigate the efficacy and safety of sirolimus in patients with MSA using a futility design. We also analyzed 1-year biomarker trajectories in the trial participants.. Randomized, double-blind, parallel group, placebo-controlled clinical trial at the New York University of patients with probable MSA randomly assigned (3:1) to sirolimus (2-6 mg daily) for 48 weeks or placebo. Primary endpoint was change in the Unified MSA Rating Scale (UMSARS) total score from baseline to 48 weeks. (ClinicalTrials.gov NCT03589976).. The trial was stopped after a pre-planned interim analysis met futility criteria. Between August 15, 2018 and November 15, 2020, 54 participants were screened, and 47 enrolled and randomly assigned (35 sirolimus, 12 placebo). Of those randomized, 34 were included in the intention-to-treat analysis. There was no difference in change from baseline to week 48 between the sirolimus and placebo in UMSARS total score (mean difference, 2.66; 95% CI, -7.35-6.91; P = 0.648). There was no difference in UMSARS-1 and UMSARS-2 scores either. UMSARS scores changes were similar to those reported in natural history studies. Neuroimaging and blood biomarker results were similar in the sirolimus and placebo groups. Adverse events were more frequent with sirolimus. Analysis of 1-year biomarker trajectories in all participants showed that increases in blood neurofilament light chain (NfL) and reductions in whole brain volume correlated best with UMSARS progression.. Sirolimus for 48 weeks was futile to slow the progression of MSA and had no effect on biomarkers compared to placebo. One-year change in blood NfL and whole brain atrophy are promising biomarkers of disease progression for future clinical trials. © 2022 International Parkinson and Movement Disorder Society.

Topics: alpha-Synuclein; Double-Blind Method; Humans; Medical Futility; Multiple System Atrophy; Sirolimus; TOR Serine-Threonine Kinases; Treatment Outcome

Multiple system atrophy (MSA) is a rare and fatal neurodegenerative disease with limited symptomatic treatment options. Aggregation of α-synuclein in oligodendrocytes is believed to be a central mechanism of the neurodegenerative process. PD01A and PD03A are 2 novel therapeutic vaccine candidates containing short peptides as antigenic moieties that are designed to induce a sustained antibody response, specifically targeting pathogenic assemblies of α-synuclein. The objectives of the current study were to evaluate primarily the safety and tolerability of PD01A and PD03A in patients with early MSA. Thirty patients (11 women) were randomized to receive 5 subcutaneous injections of either PD01A (n = 12), PD03A (n = 12), or placebo (n = 6) in this patient- and examiner-blinded, placebo-controlled, 52-week phase 1 clinical trial (ClinicalTrial.gov identifier: NCT02270489). Immunogenicity and clinical scores were assessed as secondary objectives. Twenty-nine patients reported a total of 595 treatment-emergent adverse events (mild or moderate, n = 555; severe, n = 40). Treatment-related adverse events included 190 injection-site reactions typically observed in vaccination trials with similar per-subject incidence in the treatment groups over time. Sustained IgG titers were observed in the PD01A-treated group, and 89% of treated patients developed a PD01-specific antibody response after receiving all injections. Induced antibodies displayed clear reactivity to the α-synuclein target epitope. Titers and antibody responder rate (58%) were lower in the PD03A-treated group. In conclusion, both PD01A and PD03A were safe and well tolerated. PD01A triggered a rapid and long-lasting antibody response that specifically targeted the α-synuclein epitope. © 2020 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

Topics: alpha-Synuclein; Female; Humans; Male; Multiple System Atrophy; Parkinson Disease; Peptides; Vaccination

Multiple system atrophy (MSA) is a progressive neurodegenerative disorder characterized by parkinsonism, cerebellar ataxia and autonomic dysfunction. Pathogenic mechanisms remain obscure but the neuropathological hallmark is the presence of alpha-synuclein-immunoreactive glial cytoplasmic inclusions. Genetic variants of the alpha-synuclein gene, SNCA, are thus strong candidates for genetic association with MSA. One follow-up to a genome-wide association of Parkinson's disease has identified association of a SNP in SNCA with MSA.. We evaluated 32 SNPs in the SNCA gene in a European population of 239 cases and 617 controls recruited as part of the Neuroprotection and Natural History in Parkinson Plus Syndromes (NNIPPS) study. We used 161 independently collected samples for replication. Two SNCA SNPs showed association with MSA: rs3822086 (P = 0.0044), and rs3775444 (P = 0.012), although only the first survived correction for multiple testing. In the MSA-C subgroup the association strengthened despite more than halving the number of cases: rs3822086 P = 0.0024, OR 2.153, (95% CI 1.3-3.6); rs3775444 P = 0.0017, OR 4.386 (95% CI 1.6-11.7). A 7-SNP haplotype incorporating three SNPs either side of rs3822086 strengthened the association with MSA-C further (best haplotype, P = 8.7 x 10(-4)). The association with rs3822086 was replicated in the independent samples (P = 0.035).. We report a genetic association between MSA and alpha-synuclein which has replicated in independent samples. The strongest association is with the cerebellar subtype of MSA.. ClinicalTrials.gov NCT00211224.

Topics: Aged; alpha-Synuclein; Case-Control Studies; Female; Genetic Variation; Genotype; Humans; Male; Microsatellite Repeats; Middle Aged; Multiple System Atrophy; Polymorphism, Single Nucleotide; Quality Control

Multiple system atrophy is a progressive neurodegenerative disease with prominent autonomic and motor features. During early stages, different subtypes of the disease are distinguished by their predominant parkinsonian or cerebellar symptoms, reflecting its heterogeneous nature. The pathognomonic feature of multiple system atrophy is the presence of α-synuclein (αSyn) protein deposits in oligodendroglial cells. αSyn can assemble in specific cellular or disease environments and form αSyn strains with unique structural features, but the ability of αSyn strains to propagate in oligodendrocytes remains elusive. Recently, it was shown that αSyn strains with related conformations exist in the brains of patients. Here, we investigated whether different αSyn strains can influence multiple system atrophy progression in a strain-dependent manner. To this aim, we injected two recombinant αSyn strains (fibrils and ribbons) in multiple system atrophy transgenic mice and found that they determined disease severity in multiple system atrophy via host-restricted and cell-specific pathology in vivo. αSyn strains significantly impact disease progression in a strain-dependent way via oligodendroglial, neurotoxic and immune-related mechanisms. Neurodegeneration and brain atrophy were accompanied by unique microglial and astroglial responses and the recruitment of central and peripheral immune cells. The differential activation of microglial cells correlated with the structural features of αSyn strains both in vitro and in vivo. Spectral analysis showed that ribbons propagated oligodendroglial inclusions that were structurally distinct from those of fibrils, with resemblance to oligodendroglial inclusions, in the brains of patients with multiple system atrophy. This study, therefore, shows that the multiple system atrophy phenotype is governed by both the nature of the αSyn strain and the host environment and that by injecting αSyn strains into an animal model of the disease, a more comprehensive phenotype can be established.

Topics: alpha-Synuclein; Animals; Brain; Disease Models, Animal; Mice; Mice, Transgenic; Multiple System Atrophy; Patient Acuity

Multiple system atrophy (MSA) is characterized by accumulation of phosphorylated α-synuclein (p-syn) as glial cytoplasmic inclusions in the brain and a specific biomarker for this disorder is urgently needed. We aimed at investigating if p-syn can also be detected in skin Remak non-myelinating Schwann cells (RSCs) as Schwann cell cytoplasmic inclusions (SCCi) and may represent a reliable clinical biomarker for MSA. This cross-sectional diagnostic study evaluated skin p-syn in 96 patients: 46 with probable MSA (29 with parkinsonism type MSA and 17 with cerebellar type MSA), 34 with Parkinson's disease (PD) and 16 with dementia with Lewy bodies (DLB). We also included 50 healthy control subjects. Patients were recruited from five different medical centres. P-syn aggregates in skin sections were stained by immunofluorescence, followed by analyses with confocal microscopy and immuno-electron microscopy. All analyses were performed in a blinded fashion. Overall, p-syn aggregates were found in 78% of MSA patients and 100% of patients with PD/DLB, whereas they could not be detected in controls. As for neuronal aggregates 78% of MSA patients were positive for p-syn in somatic neurons, whereas all PD/DLB patients were positive in autonomic neurons. When analysing the presence of p-syn in RSCs, 74% of MSA patients were positive, whereas no such SCCi could be observed in PD/DLB patients. Analyses by immuno-electron microscopy confirmed that SCCi were only found in cases with MSA and thus absent in those with PD/DLB. In conclusion, our findings demonstrate that (i) fibrillar p-syn in RSCs is a pathological hallmark of MSA and may be used as a specific and sensitive disease biomarker; (ii) in Lewy body synucleinopathies (PD/DLB) only neurons contain p-syn deposits; and (iii) the cell-specific deposition of p-syn in the skin thus mirrors that of the brain in many aspects and suggests that non-myelinated glial cells are also involved in the MSA pathogenesis.

Topics: alpha-Synuclein; Alzheimer Disease; Biomarkers; Cross-Sectional Studies; Humans; Lewy Body Disease; Multiple System Atrophy; Parkinson Disease; Schwann Cells

Topics: alpha-Synuclein; Humans; Multiple System Atrophy

Topics: alpha-Synuclein; Brain; Humans; Multiple System Atrophy; Neuroglia

The pathological hallmark of multiple system atrophy (MSA) is aberrant accumulation of phosphorylated α-synuclein in oligodendrocytes, forming glial cytoplasmic inclusions (GCIs). Extensive demyelination occurs particularly in the olivopontocerebellar and striatonigral pathways, but its precise mechanism remains elusive. Glial connexins (Cxs), which form gap junction channels between astrocytes and oligodendrocytes, play critical roles in myelin maintenance, and have not been studied in MSA. Therefore, we immunohistochemically investigated glial Cx changes in the cerebellar afferent fibers in 15 autopsied patients with MSA. We classified demyelinating lesions into three stages based on Klüver-Barrera staining: early (Stage I), intermediate (Stage II), and late (Stage III) stages showing subtle, moderate, and severe myelin reduction, respectively. Myelin-associated glycoprotein, but not myelin oligodendrocyte glycoprotein, was preferentially decreased in Stage I, suggesting distal oligodendrogliopathy type demyelination. Accumulation of phosphorylated α-synuclein in oligodendrocytes was frequently seen in Stage I but less frequently observed in Stages II and III. Tubulin polymerization-promoting protein (TPPP/p25α)-positive oligodendrocytes were preserved in Stage I but successively decreased in Stages II and III. Even at Stage I, Cx32 was nearly absent from myelin, despite the relative preservation of other nodal proteins, such as neurofascin, claudin-11/oligodendrocyte-specific protein, and contactin-associated protein 1, which successively decreased in the later stages. Cx32 was re-distributed in the oligodendrocyte cytoplasm and co-localized with GCIs. Cx47 gradually decreased at the oligodendrocyte surface in a stage-dependent manner but was not co-localized with GCIs. Astrocytic Cx43 was down-regulated in Stage I but up-regulated in Stages II and III, reflecting astrogliosis. Cx43/Cx47 gap junctions significantly decreased from Stage I to III. Activated microglia/macrophages and T cells infiltrated in Stage I rather than Stages II and III. Therefore, early and extensive alterations of glial Cxs, particularly Cx32 loss, occur in MSA and may accelerate distal oligodendrogliopathy type demyelination and nodal/paranodal dysfunction through disruption of inter-glial communication.

Topics: alpha-Synuclein; Connexin 43; Connexins; Demyelinating Diseases; Humans; Multiple System Atrophy

Somatic α-synuclein (SNCA) copy number variants (CNVs, specifically gains) occur in multiple system atrophy (MSA) and Parkinson's disease brains.. The aim was to compare somatic SNCA CNVs in MSA subtypes (striatonigral degeneration [SND] and olivopontocerebellar atrophy [OPCA]) and correlate with inclusions.. We combined fluorescent in situ hybridization with immunofluorescence for α-synuclein and in some cases oligodendrocyte marker tubulin polymerization promoting protein (TPPP).. We analyzed one to three brain regions from 24 MSA cases (13 SND, 11 OPCA). In a region preferentially affected in one subtype (putamen in SND, cerebellum in OPCA), mosaicism was higher in that subtype, and cells with CNVs were 4.2 times more likely to have inclusions. In the substantia nigra, nonpigmented cells with CNVs and TPPP were about six times more likely to have inclusions.. The correlation between SNCA CNVs and pathology (at a regional level) and inclusions (at a single-cell level) suggests a role for somatic SNCA CNVs in MSA pathogenesis. © 2022 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

Topics: alpha-Synuclein; DNA Copy Number Variations; Humans; In Situ Hybridization, Fluorescence; Multiple System Atrophy; Olivopontocerebellar Atrophies

Epidemiological studies show correlations between constipation and development of Parkinson's disease (PD); however, few studies have explored the association between constipation and dementia with Lewy bodies (DLB), Parkinson's disease dementia (PDD), and multiple system atrophy (MSA). We sought to explore the lifelong association of constipation and PD, DLB, PDD, and MSA (α-Synucleinopathies), compared to age- and sex-matched controls.. Using the Rochester Epidemiology Project (REP), we established an incident cohort of clinically defined α-synucleinopathies. A movement-disorder specialist reviewed all medical charts to establish clinical diagnoses.. We identified 453 incident cases of clinically diagnosed α-synucleinopathies and an identical number of age- and sex-matched controls in Olmsted County (MN), 1991-2010. There were 303 cases of PD; 80, DLB; 54, PDD; and 16, MSA. Approximately 50% of α-synucleinopathies of all types reported constipation, compared to 27% in controls. The earliest pre-motor onset constipation was in DLB (median, 3.76 years prior to α-synucleinopathies motor-symptom onset); latest onset post-motor constipation was in PD (median, 5.15 years after motor-symptom onset). PD also had the highest longstanding constipation rate (18.2%). All α-synucleinopathies had higher odds of constipation compared to controls, except for MSA (p = 0.09), likely due to a limited sample size.. PD, DLB, and PDD had higher odds of constipation compared to controls; PD had the most widespread onset of lifelong constipation, both longstanding and pre- or post-motor onset symptoms. Our results indicate that constipation rates do not differ among α-synucleinopathies but do differ in terms of temporal onset compared to disease onset.

Topics: alpha-Synuclein; Chronic Disease; Constipation; Dementia; Humans; Lewy Body Disease; Minnesota; Multiple System Atrophy; Parkinson Disease; Synucleinopathies

Multiple system atrophy of the parkinsonian type (MSA-P) is a rare, fatal neurodegenerative disease with sporadic onset. It is still unknown if MSA-P is a primary oligodendropathy or caused by neuronal pathophysiology leading to severe, α-synuclein-associated neurodegeneration, mainly in the striatum. In this study, we generated and differentiated induced pluripotent stem cells (iPSCs) from patients with the clinical diagnosis of probable MSA-P (

Topics: alpha-Synuclein; GABAergic Neurons; Humans; Induced Pluripotent Stem Cells; Medium Spiny Neurons; Multiple System Atrophy

As our understanding of the pathogenesis of multiple system atrophy (MSA) continues to advance, significant research has focused on the development of disease-modifying therapies. In addition to inhibiting the aggregation of α-synuclein (αS) protein, a major culprit of MSA pathogenesis, disease-modifying drugs have been developed to mitigate cell-to-cell transmission of aggregated αS, thereby suppressing subsequent neuroinflammation, and release of trophic factors. However, most of these therapies have been unsuccessful. The diagnostic criteria for MSA have recently been revised to allow for earlier and more reliable diagnosis. In addition, clear criteria for prodromal MSA have been established, which is expected to narrow the translational gap.

Topics: alpha-Synuclein; Humans; Multiple System Atrophy

The amyloid aggregation of alpha-synuclein within the brain is associated with the pathogenesis of Parkinson's disease (PD) and other related synucleinopathies, including multiple system atrophy (MSA). Alpha-synuclein aggregates are a major therapeutic target for treatment of these diseases. We identify two small molecules capable of disassembling preformed alpha-synuclein fibrils. The compounds, termed CNS-11 and CNS-11g, disaggregate recombinant alpha-synuclein fibrils in vitro, prevent the intracellular seeded aggregation of alpha-synuclein fibrils, and mitigate alpha-synuclein fibril cytotoxicity in neuronal cells. Furthermore, we demonstrate that both compounds disassemble fibrils extracted from MSA patient brains and prevent their intracellular seeding. They also reduce in vivo alpha-synuclein aggregates in

Topics: alpha-Synuclein; Amyloid; Animals; Brain; Caenorhabditis elegans; Mice; Multiple System Atrophy; Parkinson Disease; Synucleinopathies

Although multiple sclerosis (MS) and multiple system atrophy (MSA) are both characterized by impaired oligodendrocytes (OLs), the aetiological relevance remains obscure. Given inherent stressors affecting OLs, the objective of the present study was to discuss the possible role of amyloidogenic evolvability (aEVO) in these conditions. Hypothetically, in aEVO, protofibrils of amyloidogenic proteins (APs), including β-synuclein and β-amyloid, might form in response to diverse stressors in parental brain. Subsequently, the AP protofibrils might be transmitted to offspring via germ cells in a prion-like fashion. By virtue of the stress information conferred by protofibrillar APs, the OLs in offspring's brain might be more resilient to forthcoming stressors, perhaps reducing MS risk. aEVO could be comparable to a gene for the inheritance of acquired characteristics. On the contrary, during ageing, MSA risk is increased through antagonistic pleiotropy. Consistently, the expression levels of APs are reduced in MS, but are increased in MSA compared to controls. Furthermore, β-synuclein, the non-amyloidogenic homologue of β-synuclein, might exert a buffering effect on aEVO, and abnormal β-synuclein could also increase MS and MSA disease activity. Collectively, a better understanding of the role of aEVO in the OL diseases might lead to novel interventions for such chronic degenerative conditions.

Topics: alpha-Synuclein; Amyloidogenic Proteins; beta-Synuclein; Brain; Humans; Multiple Sclerosis; Multiple System Atrophy

α-Synucleinopathies are spreading neurodegenerative disorders characterized by the intracellular accumulation of insoluble aggregates populated by α-Synuclein (α-Syn) fibrils. In Parkinson's disease (PD) and dementia with Lewy bodies, intraneuronal α-Syn aggregates are referred to as Lewy bodies in the somata and as Lewy neurites in the neuronal processes. In multiple system atrophy (MSA) α-Syn aggregates are also found within mature oligodendrocytes (OLs) where they form Glial Cytoplasmic Inclusions (GCIs). However, the origin of GCIs remains enigmatic: (i) mature OLs do not express α-Syn, precluding the seeding and the buildup of inclusions and (ii) the artificial overexpression of α-Syn in OLs of transgenic mice results in a burden of soluble phosphorylated α-Syn but fails to form α-Syn fibrils. In contrast, mass spectrometry of α-Syn fibrillar aggregates from MSA patients points to the neuronal origin of the proteins intimately associated with the fibrils within the GCIs. This suggests that GCIs are preassembled in neurons and only secondarily incorporated into OLs. Interestingly, we recently isolated a synthetic human α-Syn fibril strain (1B fibrils) capable of seeding a type of neuronal inclusion observed early and specifically during MSA. Our goal was thus to investigate whether the neuronal α-Syn pathology seeded by 1B fibrils could eventually be transmitted to OLs to form GCIs in vivo. After confirming that mature OLs did not express α-Syn to detectable levels in the adult mouse brain, a series of mice received unilateral intra-striatal injections of 1B fibrils. The resulting α-Syn pathology was visualized using phospho-S129 α-Syn immunoreactivity (pSyn). We found that even though 1B fibrils were injected unilaterally, many pSyn-positive neuronal somas were present in layer V of the contralateral perirhinal cortex after 6 weeks. This suggested a fast retrograde spread of the pathology along the axons of crossing cortico-striatal neurons. We thus scrutinized the posterior limb of the anterior commissure, i.e., the myelinated interhemispheric tract containing the axons of these neurons: we indeed observed numerous pSyn-positive linear Lewy Neurites oriented parallel to the commissural axis, corresponding to axonal segments filled with aggregated α-Syn, with no obvious signs of OL α-Syn pathology at this stage. After 6 months however, the commissural Lewy neurites were no longer parallel but fragmented, curled up, sometimes squeezed in-between two c

Topics: alpha-Synuclein; Animals; Brain; Humans; Inclusion Bodies; Lewy Bodies; Mice; Mice, Transgenic; Multiple System Atrophy; Neurites; Oligodendroglia; Synucleinopathies

Although hippocampal pathologies of multiple system atrophy (MSA) and their association with dementia have been reported, no studies have reported clinicopathological differences among MSA patients with and without neuronal cytoplasmic inclusions (NCIs) in the dentate gyrus (dntNCIs). We investigated hippocampal NCI pathology in 18 MSA patient autopsies, focusing on phosphorylated α-synuclein (pAS)- and phosphorylated tau (pT)-positive dntNCIs. There were 8 MSA patients without and 10 with dntNCIs. The latter group was subclassified by immunophenotype: those with pAS-positive dntNCIs (pAS-dntNCI subtype), those with pT-positive dntNCIs (pT-dntNCI subtype), and those with both types of dntNCIs. MSA patients with dntNCIs survived longer with prolonged tracheostomy and had dementia more frequently than those without dntNCIs. The brain weights of patients with dntNCIs were lower than those without dntNCIs. The presence of dementia was similar among the dntNCI subtypes. The pAS-dntNCI subtype was associated with longer survival and smaller brain weights; the pT-dntNCI subtype exhibited more frequent tau pathologies than the pAS-dntNCI subtype. Thus, MSA with dntNCIs is a possible pathological subtype of longer survivors that correlates with longer disease duration, prolonged tracheostomy, and high frequency of dementia. Understanding clinicopathological differences in MSA patients with and without dntNCIs may lead to improved personalized management strategies.

Topics: alpha-Synuclein; Brain; Dementia; Dentate Gyrus; Hippocampus; Humans; Inclusion Bodies; Multiple System Atrophy

A 21-nucleotide duplication in one allele of SNCA was identified in a previously described disease with abundant α-synuclein inclusions that we now call juvenile-onset synucleinopathy (JOS). This mutation translates into the insertion of MAAAEKT after residue 22 of α-synuclein, resulting in a protein of 147 amino acids. Both wild-type and mutant proteins were present in sarkosyl-insoluble material that was extracted from frontal cortex of the individual with JOS and examined by electron cryo-microscopy. The structures of JOS filaments, comprising either a single protofilament, or a pair of protofilaments, revealed a new α-synuclein fold that differs from the folds of Lewy body diseases and multiple system atrophy (MSA). The JOS fold consists of a compact core, the sequence of which (residues 36-100 of wild-type α-synuclein) is unaffected by the mutation, and two disconnected density islands (A and B) of mixed sequences. There is a non-proteinaceous cofactor bound between the core and island A. The JOS fold resembles the common substructure of MSA Type I and Type II dimeric filaments, with its core segment approximating the C-terminal body of MSA protofilaments B and its islands mimicking the N-terminal arm of MSA protofilaments A. The partial similarity of JOS and MSA folds extends to the locations of their cofactor-binding sites. In vitro assembly of recombinant wild-type α-synuclein, its insertion mutant and their mixture yielded structures that were distinct from those of JOS filaments. Our findings provide insight into a possible mechanism of JOS fibrillation in which mutant α-synuclein of 147 amino acids forms a nucleus with the JOS fold, around which wild-type and mutant proteins assemble during elongation.

Topics: alpha-Synuclein; Humans; Multiple System Atrophy; Mutation; Nigeria; Synucleinopathies

Topics: alpha-Synuclein; Brain; Humans; JC Virus; Multiple System Atrophy

Symptoms in the urogenital organs are common in multiple system atrophy (MSA), also in the years preceding the MSA diagnosis. It is unknown how MSA is triggered and these observations in prodromal MSA led us to hypothesize that synucleinopathy could be triggered by infection of the genitourinary tract causing ɑ-synuclein (ɑSyn) to aggregate in peripheral nerves innervating these organs. As a first proof that peripheral infections could act as a trigger in MSA, this study focused on lower urinary tract infections (UTIs), given the relevance and high frequency of UTIs in prodromal MSA, although other types of infection might also be important triggers of MSA. We performed an epidemiological nested-case control study in the Danish population showing that UTIs are associated with future diagnosis of MSA several years after infection and that it impacts risk in both men and women. Bacterial infection of the urinary bladder triggers synucleinopathy in mice and we propose a novel role of ɑSyn in the innate immune system response to bacteria. Urinary tract infection with uropathogenic E. coli results in the de novo aggregation of ɑSyn during neutrophil infiltration. During the infection, ɑSyn is released extracellularly from neutrophils as part of their extracellular traps. Injection of MSA aggregates into the urinary bladder leads to motor deficits and propagation of ɑSyn pathology to the central nervous system in mice overexpressing oligodendroglial ɑSyn. Repeated UTIs lead to progressive development of synucleinopathy with oligodendroglial involvement in vivo. Our results link bacterial infections with synucleinopathy and show that a host response to environmental triggers can result in ɑSyn pathology that bears semblance to MSA.

Topics: alpha-Synuclein; Animals; Case-Control Studies; Escherichia coli; Female; Immunity, Innate; Mice; Mice, Transgenic; Multiple System Atrophy; Synucleinopathies; Urinary Tract Infections

Multiple system atrophy (MSA) is a neurodegenerative disease characterized by the accumulation of misfolded α-synuclein (αSyn) and myelin disruption. However, the mechanism underlying αSyn accumulation in MSA brains remains unclear. Here, we aimed to identify epsin-2 as a potential regulator of αSyn propagation in MSA brains. In the MSA mouse model, PLP-hαSyn mice, and FABP7/αSyn hetero-aggregate-injected mice, we initially discovered that fatty acid-binding protein 7 (FABP7) is related to MSA development and forms hetero-aggregates with αSyn, which exhibit stronger toxicity than αSyn aggregates. Moreover, the injected FABP7/αSyn hetero-aggregates in mice selectively accumulated only in oligodendrocytes and Purkinje neurons, causing cerebellar dysfunction. Furthermore, bioinformatic analyses of whole blood from MSA patients and FABP7 knockdown mice revealed that epsin-2, a protein expressed in both oligodendrocytes and Purkinje cells, could potentially regulate FABP7/αSyn hetero-aggregate propagation via clathrin-dependent endocytosis. Lastly, adeno-associated virus type 5-dependent epsin-2 knockdown mice exhibited decreased levels of αSyn aggregate accumulation in Purkinje neurons and oligodendrocytes, as well as improved myelin levels and Purkinje neuron function in the cerebellum and motor performance. These findings suggest that epsin-2 plays a significant role in αSyn accumulation in MSA, and we propose epsin-2 as a novel therapeutic target for MSA.

Topics: alpha-Synuclein; Animals; Brain; Fatty Acid-Binding Protein 7; Mice; Mice, Transgenic; Multiple System Atrophy; Oligodendroglia

Multiple system atrophy (MSA) is a sporadic adult-onset rare neurodegenerative synucleinopathy for which counteracting central nervous system insulin resistance bears the potential of being neuroprotective. G-protein-(heterotrimeric guanine nucleotide-binding protein)-coupled receptor kinase 2 (GRK2) is emerging as a physiologically relevant inhibitor of insulin signaling.. We tested whether lowering brain GRK2 abundance may reverse insulin-resistance.. We lowered brain GRK2 abundance through viral-mediated delivery of a GRK2-specific miRNA and quantified the reversion of a developing or an established insulin-resistant phenotype using the transgenic PLP-SYN mouse model of MSA.. Viral vector delivery of a GRK2 miRNA demonstrated a neuroprotective capacity when administered (1) in utero intracerebroventricularly in developing PLP-SYN mice and (2) intrastriatally in adult PLP-SYN mice. Decreased striatal GRK2 levels correlated in both designs with neuroprotection of the substantia nigra dopamine neurons, reduction in high-molecular-weight species of α-synuclein, and reduced insulin resistance.. These data support GRK2 as a potential therapeutic target in MSA. © 2023 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

Topics: alpha-Synuclein; Animals; Disease Models, Animal; Insulin Resistance; Insulins; Mice; Mice, Transgenic; MicroRNAs; Movement Disorders; Multiple System Atrophy

Unique strains of α-synuclein aggregates have been postulated to underlie the spectrum of clinical and pathological presentations seen across the synucleinopathies. Whereas multiple system atrophy (MSA) is associated with a predominance of oligodendroglial α-synuclein inclusions, α-synuclein aggregates in Parkinson's disease (PD) preferentially accumulate in neurons. The G51D mutation in the SNCA gene encoding α-synuclein causes an aggressive, early-onset form of PD that exhibits clinical and neuropathological traits reminiscent of both PD and MSA. To assess the strain characteristics of G51D PD α-synuclein aggregates, we performed propagation studies in M83 transgenic mice by intracerebrally inoculating patient brain extracts. The properties of the induced α-synuclein aggregates in the brains of injected mice were examined using immunohistochemistry, a conformational stability assay, and by performing α-synuclein seed amplification assays. Unlike MSA-injected mice, which developed a progressive motor phenotype, G51D PD-inoculated animals remained free of overt neurological illness for up to 18 months post-inoculation. However, a subclinical synucleinopathy was present in G51D PD-inoculated mice, characterized by the accumulation of α-synuclein aggregates in restricted regions of the brain. The induced α-synuclein aggregates in G51D PD-injected mice exhibited distinct properties in a seed amplification assay and were much more stable than those present in mice injected with MSA extract, which mirrored the differences observed between human MSA and G51D PD brain samples. These results suggest that the G51D SNCA mutation specifies the formation of a slowly propagating α-synuclein strain that more closely resembles α-synuclein aggregates associated with PD than MSA.

Topics: alpha-Synuclein; Animals; Humans; Mice; Mice, Transgenic; Multiple System Atrophy; Mutation; Parkinson Disease; Synucleinopathies

The aim of this study was to assess whether cancer occurs with increased frequency in multiple system atrophy (MSA). The pathological hallmark of MSA is glial cytoplasmic inclusions containing aggregated α-synuclein, and the related protein γ-synuclein correlates with invasive cancer. We investigated whether these two disorders are associated clinically.. Medical records of 320 patients with pathologically confirmed MSA seen between 1998 and 2022 were reviewed. After excluding those with insufficient medical histories, the remaining 269 and an equal number of controls matched for age and sex were queried for personal and family histories of cancer recorded on standardized questionnaires and in clinical histories. Additionally, age-adjusted rates of breast cancer were compared with US population incidence data.. Of 269 cases in each group, 37 with MSA versus 45 of controls had a personal history of cancer. Reported cases of cancer in parents were 97 versus 104 and in siblings 31 versus 44 for MSA and controls, respectively. Of 134 female cases in each group, 14 MSA versus 10 controls had a personal history of breast cancer. The age-adjusted rate of breast cancer in MSA was 0.83%, as compared with 0.67% in controls and 2.0% in the US population. All comparisons were nonsignificant.. The evidence from this retrospective cohort found no significant clinical association of MSA with breast cancer or other cancers. These results do not exclude the possibility that knowledge about synuclein pathology at the molecular level in cancer may lead to future discoveries and potential therapeutic targets for MSA.

Topics: alpha-Synuclein; Brain; Breast Neoplasms; Female; Humans; Multiple System Atrophy; Retrospective Studies

Abnormal α-synuclein aggregation is a key pathological feature of a group of neurodegenerative diseases known as synucleinopathies, which include Parkinson's disease (PD), dementia with Lewy bodies and multiple system atrophy (MSA). The pathogenic β-sheet seed conformation of α-synuclein is found in various tissues, suggesting potential as a biomarker, but few studies have been able to reliably detect these seeds in serum samples. In this study, we developed a modified assay system, called immunoprecipitation-based real-time quaking-induced conversion (IP/RT-QuIC), which enables the detection of pathogenic α-synuclein seeds in the serum of individuals with synucleinopathies. In our internal first and second cohorts, IP/RT-QuIC showed high diagnostic performance for differentiating PD versus controls (area under the curve (AUC): 0.96 (95% confidence interval (CI) 0.95-0.99)/AUC: 0.93 (95% CI 0.84-1.00)) and MSA versus controls (AUC: 0.64 (95% CI 0.49-0.79)/AUC: 0.73 (95% CI 0.49-0.98)). IP/RT-QuIC also showed high diagnostic performance in differentiating individuals with PD (AUC: 0.86 (95% CI 0.74-0.99)) and MSA (AUC: 0.80 (95% CI 0.65-0.97)) from controls in a blinded external cohort. Notably, amplified seeds maintained disease-specific properties, allowing the differentiation of samples from individuals with PD versus MSA. In summary, here we present a novel platform that may allow the detection of individuals with synucleinopathies using serum samples.

Topics: alpha-Synuclein; Biomarkers; Humans; Lewy Body Disease; Multiple System Atrophy; Parkinson Disease; Synucleinopathies

Posttranslational modifications of α-synuclein, such as truncation or abnormal proteolysis, are implicated in Parkinson's disease (PD), dementia with Lewy bodies (DLB), and multiple system atrophy (MSA). A key focus of this article includes the proteases responsible for inducing truncation, the specific sites susceptible to truncation, and the resultant influence of these truncated species on the seeding and aggregation of endogenous α-synuclein. We also shed light on the unique structural attributes of these truncated species, and how these modifications can lead to distinctive forms of synucleinopathies. In addition, we explore the comparative toxic potentials of various α-synuclein species. An extensive analysis of available evidence of truncated α-synuclein species in human-synucleinopathy brains is also provided. Lastly, we delve into the detrimental impact of truncated species on key cellular structures such as the mitochondria and endoplasmic reticulum. Our article discusses enzymes involved in α-synuclein truncation, including 20 S proteasome, cathepsins, asparagine endopeptidase, caspase-1, calpain-1, neurosin/kallikrein-6, matrix metalloproteinase-1/-3, and plasmin. Truncation patterns impact α-synuclein aggregation - C-terminal truncation accelerates aggregation with larger truncations correlated with shortened aggregation lag times. N-terminal truncation affects aggregation differently based on the truncation location. C-terminally truncated α-synuclein forms compact, shorter fibrils compared to the full-length (FL) protein. N-terminally truncated monomers form fibrils similar in length to FL α-synuclein. Truncated forms show distinct fibril morphologies, increased β-sheet structures, and greater protease resistance. Misfolded α-synuclein can adopt various conformations, leading to unique aggregates and distinct synucleinopathies. Fibrils, with prion-like transmission, are potentially more toxic than oligomers, though this is still debated. Different α-synuclein variants with N- and C-terminal truncations, namely 5-140, 39-140, 65-140, 66-140, 68-140, 71-140, 1-139, 1-135, 1-133, 1-122, 1-119, 1-115, 1-110, and 1-103 have been found in PD, DLB, and MSA patients' brains. In Parkinsonism, excess misfolded α-synuclein overwhelms the proteasome degradation system, resulting in truncated protein production and accumulation in the mitochondria and endoplasmic reticulum.

Topics: alpha-Synuclein; Humans; Multiple System Atrophy; Parkinson Disease; Proteasome Endopeptidase Complex; Protein Processing, Post-Translational; Proteolysis; Synucleinopathies

α-synuclein (αS) is an abundant, neuronal protein that assembles into fibrillar pathological inclusions in a spectrum of neurodegenerative diseases that include Lewy body diseases (LBD) and Multiple System Atrophy (MSA). The cellular and regional distributions of pathological inclusions vary widely between different synucleinopathies contributing to the spectrum of clinical presentations. Extensive cleavage within the carboxy (C)-terminal region of αS is associated with inclusion formation, although the events leading to these modifications and the implications for pathobiology are of ongoing study. αS preformed fibrils can induce prion-like spread of αS pathology in both in vitro and animal models of disease. Using C truncation-specific antibodies, we demonstrated here that prion-like cellular uptake and processing of αS preformed fibrils resulted in two major cleavages at residues 103 and 114. A third cleavage product (122 αS) accumulated upon application of lysosomal protease inhibitors. In vitro, both 1-103 and 1-114 αS polymerized rapidly and extensively in isolation and in the presence of full-length αS. 1-103 αS also demonstrated more extensive aggregation when expressed in cultured cells. Furthermore, we used novel antibodies to αS cleaved at residue Glu114, to assess x-114 αS pathology in postmortem brain tissue from patients with LBD and MSA, as well as three different transgenic αS mouse models of prion-like induction. The distribution of x-114 αS pathology was distinct from that of overall αS pathology. These studies reveal the cellular formation and behavior of αS C-truncated at residues 114 and 103 as well as the disease dependent distribution of x-114 αS pathology.

Topics: alpha-Synuclein; Animals; Autopsy; Glutamic Acid; Humans; Lewy Body Disease; Lysosomes; Mice; Mice, Transgenic; Multiple System Atrophy; Prions; Protease Inhibitors

Mutations or multiplications of the SNCA (Synuclein Alpha) gene cause rare autosomal dominant Parkinson's disease (PD). The SNCA G51D missense mutation is associated with a synucleinopathy that shares PD and multiple system atrophy (MSA) characteristics. We generated induced pluripotent stem cell (iPSC) lines from two individuals with SNCA G51D missense mutations at risk of PD. Dermal fibroblasts were reprogrammed to pluripotency using a non-integrating mRNA-based protocol. The resulting human iPSCs displayed normal morphology, expressed markers associated with pluripotency, and differentiated into the three germ layers. The iPSC lines could facilitate disease-modelling and therapy development studies for synucleinopathies.

Topics: alpha-Synuclein; Humans; Induced Pluripotent Stem Cells; Multiple System Atrophy; Mutation; Mutation, Missense; Parkinson Disease

Recent studies have been able to detect α-synuclein (αSyn) seeding in formaldehyde-fixed paraffin-embedded (FFPE) tissues from patients with synucleinopathies using seed amplification assays (SAAs), but with relatively low sensitivity due to limited protein extraction efficiency. With the aim of introducing an alternative option to frozen tissues, we developed a streamlined protein extraction protocol for evaluating disease-specific seeding in FFPE human brain. We evaluated the protein extraction efficiency of different tissue preparations, deparaffinizations, and protein extraction buffers using formaldehyde-fixed and FFPE tissue of a single Lewy body disease (LBD) subject. Alternatively, we incorporated heat-induced antigen retrieval and dissociation using a commercially available kit. Our novel protein extraction protocol has been optimized to work with 10 sections of 4.5-µm-thickness or 2-mm-diameter micro-punch of FFPE tissue that can be used to seed SAAs. We demonstrated that extracted proteins from FFPE still preserve seeding potential and further show disease-specific seeding in LBD and multiple system atrophy. To the best of our knowledge, our study is the first to recapitulate disease-specific αSyn seeding behaviour in FFPE human brain. Our findings open new perspectives in re-evaluating archived human brain tissue, extending the disease-specific seeding assays to larger cohorts to facilitate molecular subtyping of synucleinopathies.

Topics: alpha-Synuclein; Brain; Formaldehyde; Humans; Lewy Body Disease; Multiple System Atrophy; Paraffin; Paraffin Embedding; Synucleinopathies

Parkinson's disease (PD), multiple system atrophy (MSA), and dementia with Lewy bodies (DLB) are neurodegenerative disorders with alpha-synuclein (α-syn) aggregation pathology. Different strains of α-syn with unique properties are suggested to cause distinct clinical and pathological manifestations resulting in PD, MSA, or DLB. To study individual α-syn spreading patterns, we injected α-syn fibrils amplified from brain homogenates of two MSA patients and two PD patients into the brains of C57BI6/J mice. Antibody staining against pS129-α-syn showed that α-syn fibrils amplified from the brain homogenates of the four different patients caused different levels of α-syn spreading. The strongest α-syn pathology was triggered by α-syn fibrils of one of the two MSA patients, followed by comparable pS129-α-syn induction by the second MSA and one PD patient material. Histological analysis using an antibody against Iba1 further showed that the formation of pS129-α-syn is associated with increased microglia activation. In contrast, no differences in dopaminergic neuron numbers or co-localization of α-syn in oligodendrocytes were observed between the different groups. Our data support the spreading of α-syn pathology in MSA, while at the same time pointing to spreading heterogeneity between different patients potentially driven by individual patient immanent factors.

Topics: alpha-Synuclein; Animals; Antibodies; Brain; Mice; Multiple System Atrophy; Parkinson Disease; Synucleinopathies

Topics: alpha-Synuclein; Humans; Multiple System Atrophy; Parkinson Disease; Parkinsonian Disorders

The accumulation of α-synuclein (α-syn), an essential step in PD development and progression, is observed not only in neurons but also in glia, including astrocytes. The mechanisms regulating astrocytic α-syn level and aggregation remain unclear. More recently, it has been demonstrated that a part of α-syn spreading occurs through extracellular vesicles (EVs), although it is unknown whether this process is involved in astrocytes of PD. It is known, however, that EVs derived from the central nervous system exist in the blood and are extensively explored as biomarkers for PD and other neurodegenerative disorders.. Primary astrocytes were transfected with A53T α-syn plasmid or exposed to α-syn aggregates. The level of astrocyte-derived EVs (AEVs) was assessed by nanoparticle tracking analysis and immunofluorescence. The lysosomal function was evaluated by Cathepsin assays, immunofluorescence for levels of Lamp1 and Lamp2, and LysoTracker Red staining. The Apogee assays were optimized to measure the GLT-1. The number of AEVs significantly increased in primary astrocytes with α-syn deposition. The mechanism of increased AEVs was partially attributed to lysosomal dysfunction. The number of α-syn-carrying AEVs was significantly higher in patients with PD than in HC and MSA. The integrative model combining AEVs with total and aggregated α-syn exhibited efficient diagnostic power in differentiating PD from HC with an AUC of 0.915, and from MSA with an AUC of 0.877.. Pathological α-syn deposition could increase the astrocytic secretion of EVs, possibly through α-syn-induced lysosomal dysfunction. The α-syn-containing AEVs in the peripheral blood may be an effective biomarker for clinical diagnosis or differential diagnosis of PD.

Topics: alpha-Synuclein; Astrocytes; Extracellular Vesicles; Humans; Multiple System Atrophy; Parkinson Disease

Abnormal α-synuclein (α-syn) aggregation characterizes α-synucleinopathies, including Parkinson's disease (PD) and multiple system atrophy (MSA). However, no suitable positron emission tomography (PET) radiotracer for imaging α-syn in PD and MSA exists currently. Our structure-activity relationship studies identified 4-methoxy-

Topics: alpha-Synuclein; Alzheimer Disease; Amyloid beta-Peptides; Animals; Brain; Multiple System Atrophy; Parkinson Disease; Positron-Emission Tomography

A positron emission tomography (PET) tracer detecting α-synuclein pathology will improve the diagnosis, and ultimately the treatment of α-synuclein-related diseases. Here we show that the PET ligand, [

Topics: alpha-Synuclein; Humans; Multiple System Atrophy; Parkinson Disease; Positron-Emission Tomography

Fibrils of the protein α-synuclein (Asyn) are implicated in the pathogenesis of Parkinson Disease, Lewy Body Dementia, and Multiple System Atrophy. Numerous forms of Asyn fibrils have been studied by solid-state NMR and resonance assignments have been reported. Here, we report a new set of

Topics: alpha-Synuclein; Humans; Lewy Body Disease; Multiple System Atrophy; Nuclear Magnetic Resonance, Biomolecular; Parkinson Disease

Many neurodegenerative diseases including frontotemporal lobar degeneration (FTLD), Lewy body disease (LBD), multiple system atrophy (MSA), etc., show colocalized deposits of TDP-43 and α-synuclein (αS) aggregates. To understand whether these colocalizations are driven by specific molecular interactions between the two proteins, we previously showed that the prion-like C-terminal domain of TDP-43 (TDP-43PrLD) and αS synergistically interact to form neurotoxic heterotypic amyloids in homogeneous buffer conditions. However, it remains unclear if αS can modulate TDP-43 present within liquid droplets and biomolecular condensates called stress granules (SGs). Here, using cell culture and in vitro TDP-43PrLD - RNA liquid droplets as models along with microscopy, nanoscale AFM-IR spectroscopy, and biophysical analyses, we uncover the interactions of αS with phase-separated droplets. We learn that αS acts as a Pickering agent by forming clusters on the surface of TDP-43PrLD - RNA droplets. The aggregates of αS on these clusters emulsify the droplets by nucleating the formation of heterotypic TDP-43PrLD amyloid fibrils, structures of which are distinct from those derived from homogenous solutions. Together, these results reveal an intriguing property of αS to act as a Pickering agent while interacting with SGs and unmask the hitherto unknown role of αS in modulating TDP-43 proteinopathies.

Topics: alpha-Synuclein; Amyloid; DNA-Binding Proteins; Humans; Multiple System Atrophy; Prions; RNA

An elevation in iron levels, together with an accumulation of α-synuclein within the oligodendrocytes, are features of the rare atypical parkinsonian disorder, Multiple System Atrophy (MSA). We have previously tested the novel compound ATH434 (formally called PBT434) in preclinical models of Parkinson's disease and shown that it is brain-penetrant, reduces iron accumulation and iron-mediated redox activity, provides neuroprotection, inhibits alpha synuclein aggregation and lowers the tissue levels of alpha synuclein. The compound was also well-tolerated in a first-in-human oral dosing study in healthy and older volunteers with a favorable, dose-dependent pharmacokinetic profile.. To evaluate the efficacy of ATH434 in a mouse MSA model.. The PLP-α-syn transgenic mouse overexpresses α-synuclein, demonstrates oligodendroglial pathology, and manifests motor and non-motor aspects of MSA. Animals were provided ATH434 (3, 10, or 30 mg/kg/day spiked into their food) or control food for 4 months starting at 12 months of age and were culled at 16 months. Western blot was used to assess oligomeric and urea soluble α-synuclein levels in brain homogenates, whilst stereology was used to quantitate the number of nigral neurons and glial cell inclusions (GCIs) present in the substantia nigra pars compacta.. ATH434 reduced oligomeric and urea soluble α-synuclein aggregation, reduced the number of GCIs, and preserved SNpc neurons. In vitro experiments suggest that ATH434 prevents the formation of toxic oligomeric "species of synuclein".. ATH434 is a promising small molecule drug candidate that has potential to move forward to trial for treating MSA.

Topics: alpha-Synuclein; Animals; Disease Models, Animal; Humans; Iron; Mice; Mice, Transgenic; Multiple System Atrophy; Parkinson Disease; Urea

Topics: alpha-Synuclein; Frontotemporal Lobar Degeneration; Humans; Multiple System Atrophy; Parkinsonian Disorders; Synucleinopathies

Several studies have confirmed the α-synuclein real-time quaking-induced conversion (RT-QuIC) assay to have high sensitivity and specificity for Parkinson's disease. However, whether the assay can be used as a robust, quantitative measure to monitor disease progression, stratify different synucleinopathies and predict disease conversion in patients with idiopathic REM sleep behaviour disorder remains undetermined. The aim of this study was to assess the diagnostic value of CSF α-synuclein RT-QuIC quantitative parameters in regard to disease progression, stratification and conversion in synucleinopathies. We performed α-synuclein RT-QuIC in the CSF samples from 74 Parkinson's disease, 24 multiple system atrophy and 45 idiopathic REM sleep behaviour disorder patients alongside 55 healthy controls, analysing quantitative assay parameters in relation to clinical data. α-Synuclein RT-QuIC showed 89% sensitivity and 96% specificity for Parkinson's disease. There was no correlation between RT-QuIC quantitative parameters and Parkinson's disease clinical scores (e.g. Unified Parkinson's Disease Rating Scale motor), but RT-QuIC positivity and some quantitative parameters (e.g. Vmax) differed across the different phenotype clusters. RT-QuIC parameters also added value alongside standard clinical data in diagnosing Parkinson's disease. The sensitivity in multiple system atrophy was 75%, and CSF samples showed longer T50 and lower Vmax compared to Parkinson's disease. All RT-QuIC parameters correlated with worse clinical progression of multiple system atrophy (e.g. change in Unified Multiple System Atrophy Rating Scale). The overall sensitivity in idiopathic REM sleep behaviour disorder was 64%. In three of the four longitudinally followed idiopathic REM sleep behaviour disorder cohorts, we found around 90% sensitivity, but in one sample (DeNoPa) diagnosing idiopathic REM sleep behaviour disorder earlier from the community cases, this was much lower at 39%. During follow-up, 14 of 45 (31%) idiopathic REM sleep behaviour disorder patients converted to synucleinopathy with 9/14 (64%) of convertors showing baseline RT-QuIC positivity. In summary, our results showed that α-synuclein RT-QuIC adds value in diagnosing Parkinson's disease and may provide a way to distinguish variations within Parkinson's disease phenotype. However, the quantitative parameters did not correlate with disease severity in Parkinson's disease. The assay distinguished multiple system atrophy patie

Topics: alpha-Synuclein; Disease Progression; Humans; Multiple System Atrophy; Parkinson Disease; REM Sleep Behavior Disorder; Synucleinopathies

Topics: alpha-Synuclein; Biomarkers; Humans; Intermediate Filaments; Multiple System Atrophy; Parkinson Disease; Skin

The synucleinopathies are a group of neurodegenerative diseases characterized by the oligomerization of alpha-synuclein protein in neurons or glial cells. Recent studies provide data that ceramide metabolism impairment may play a role in the pathogenesis of synucleinopathies due to its influence on alpha-synuclein accumulation. The aim of the current study was to assess changes in activities of enzymes involved in ceramide metabolism in patients with different synucleinopathies (Parkinson's disease (PD), dementia with Lewy bodies (DLB), and multiple system atrophy (MSA)). The study enrolled 163 PD, 44 DLB, and 30 MSA patients as well as 159 controls. Glucocerebrosidase, alpha-galactosidase, acid sphingomyelinase enzyme activities, and concentrations of the corresponding substrates (hexosylsphingosine, globotriaosylsphingosine, lysosphingomyelin) were measured by liquid chromatography tandem-mass spectrometry in blood. Expression levels of GBA, GLA, and SMPD1 genes encoding glucoceresobridase, alpha-galactosidase, and acid sphingomyelinase enzymes, correspondently, were analyzed by real-time PCR with TaqMan assay in CD45 + blood cells. Increased hexosylsphingosine concentration was observed in DLB and MSA patients in comparison to PD and controls (p < 0.001) and it was associated with earlier age at onset (AAO) of DLB (p = 0.0008). SMPD1 expression was decreased in MSA compared to controls (p = 0.015). Acid sphingomyelinase activity was decreased in DLB, MSA patients compared to PD patients (p < 0.0001, p < 0.0001, respectively), and in MSA compared to controls (p < 0.0001). Lower acid sphingomyelinase activity was associated with earlier AAO of PD (p = 0.012). Our data support the role of lysosomal dysfunction in the pathogenesis of synucleinopathies, namely, the pronounced alterations of lysosomal activities involved in ceramide metabolism in patients with MSA and DLB.

Topics: alpha-Galactosidase; alpha-Synuclein; Ceramides; Humans; Lewy Body Disease; Multiple System Atrophy; Parkinson Disease; Sphingolipids; Sphingomyelin Phosphodiesterase; Synucleinopathies

The α-synuclein protein can adopt several different conformations that cause neurodegeneration. Different α-synuclein conformers cause at least three distinct α-synucleinopathies: multiple system atrophy (MSA), dementia with Lewy bodies (DLB), and Parkinson's disease (PD). In earlier studies, we transmitted MSA to transgenic (Tg) mice and cultured HEK cells both expressing mutant α-synuclein (A53T) but not to cells expressing α-synuclein (E46K). Now, we report that DLB is caused by a strain of α-synuclein prions that is distinct from MSA. Using cultured HEK cells expressing mutant α-synuclein (E46K), we found that DLB prions could be transmitted to these HEK cells. Our results argue that a third strain of α-synuclein prions likely causes PD, but further studies are needed to identify cells and/or Tg mice that express a mutant α-synuclein protein that is permissive for PD prion replication. Our findings suggest that other α-synuclein mutants should give further insights into α-synuclein prion replication, strain formation, and disease pathogenesis, all of which are likely required to discover effective drugs for the treatment of PD as well as the other α-synucleinopathies.

Topics: Aged; alpha-Synuclein; Cell Line; Dementia; Female; Humans; Lewy Body Disease; Male; Middle Aged; Multiple System Atrophy; Parkinson Disease; Prions; Synucleinopathies

Multiple system atrophy (MSA) is a neurodegenerative condition characterized by variable combinations of parkinsonism, autonomic failure, cerebellar ataxia and pyramidal features. Although the distribution of synucleinopathy correlates with the predominant clinical features, the burden of pathology does not fully explain observed differences in clinical presentation and rate of disease progression. We hypothesized that the clinical heterogeneity in MSA is a consequence of variability in the seeding activity of α-synuclein both between different patients and between different brain regions.. The reliable detection of α-synuclein seeding activity derived from MSA using cell-free amplification assays remains challenging. Therefore, we conducted a systematic evaluation of 168 different reaction buffers, using an array of pH and salts, seeded with fully characterized brain homogenates from one MSA and one PD patient. We then validated the two conditions that conferred the optimal ability to discriminate between PD- and MSA-derived samples in a larger cohort of 40 neuropathologically confirmed cases, including 15 MSA. Finally, in a subset of brains, we conducted the first multi-region analysis of seeding behaviour in MSA.. Using our novel buffer conditions, we show that the physicochemical factors that govern the in vitro amplification of α-synuclein can be tailored to generate strain-specific reaction buffers that can be used to reliably study the seeding capacity from MSA-derived α-synuclein. Using this novel approach, we were able to sub-categorize the 15 MSA brains into 3 groups: high, intermediate and low seeders. To further demonstrate heterogeneity in α-synuclein seeding in MSA, we conducted a comprehensive multi-regional evaluation of α-synuclein seeding in 13 different regions from 2 high seeders, 2 intermediate seeders and 2 low seeders.. We have identified unexpected differences in seed-competent α-synuclein across a cohort of neuropathologically comparable MSA brains. Furthermore, our work has revealed a substantial heterogeneity in seeding activity, driven by the PBS-soluble α-synuclein, between different brain regions of a given individual that goes beyond immunohistochemical observations. Our observations pave the way for future subclassification of MSA, which exceeds conventional clinical and neuropathological phenotyping and considers the structural and biochemical heterogeneity of α-synuclein present. Finally, our methods provide an experimental framework for the development of vitally needed, rapid and sensitive diagnostic assays for MSA.

Topics: alpha-Synuclein; Brain; Humans; Multiple System Atrophy; Parkinsonian Disorders; Synucleinopathies

The protein alpha-synuclein (αSYN) plays a central role in synucleinopathies such as Parkinsons's disease (PD) and multiple system atrophy (MSA). Presently, there are no selective αSYN positron emission tomography (PET) radioligands that do not also show affinity to amyloid-beta (Aβ). We have previously shown that radiolabeled antibodies, engineered to enter the brain via the transferrin receptor (TfR), is a promising approach for PET imaging of intrabrain targets. In this study, we used this strategy to visualize αSYN in the living mouse brain. Five bispecific antibodies, binding to both the murine TfR and αSYN were generated and radiolabeled with iodine-125 or iodine-124. All bispecific antibodies bound to αSYN and mTfR before and after radiolabelling in an ELISA assay, and bound to brain sections prepared from αSYN overexpressing mice as well as human PD- and MSA subjects, but not control tissues in autoradiography. Brain concentrations of the bispecific antibodies were between 26 and 63 times higher than the unmodified IgG format 2 h post-injection, corresponding to about 1.5% of the injected dose per gram brain tissue. Additionally, intrastriatal αSYN fibrils were visualized with PET in an αSYN deposition mouse model with one of the bispecific antibodies, [

Topics: alpha-Synuclein; Amyloid beta-Peptides; Animals; Antibodies, Bispecific; Brain; Humans; Mice; Multiple System Atrophy; Parkinson Disease; Positron-Emission Tomography; Synucleinopathies

α-Synuclein aggregates abnormally into intracellular inclusions in Parkinson's disease (PD), dementia with Lewy bodies (DLB), multiple system atrophy (MSA), and many other neurological disorders, closely connecting with their pathogenesis. The accurate tracking of α-synuclein by targeting probes is of great significance for early diagnosis, disease monitoring, and drug development. However, there have been no promising α-synuclein targeting probes for clinical application reported so far. This overview focuses on various potential α-synuclein targeting probes reported in the past two decades, including small-molecule fluorescent probes and radiolabeled probes. We provide the current status of the development of the small molecular α-synuclein imaging probes, including properties of promising imaging molecules, strategies of processing new probes, limited progress, and growth prospects in this field, expecting to help in the further development of α-synuclein targeting probes.

Topics: alpha-Synuclein; Early Diagnosis; Humans; Lewy Body Disease; Multiple System Atrophy; Parkinson Disease

Aggregated alpha-synuclein (α-synuclein) is the main component of Lewy bodies (LBs), Lewy neurites (LNs), and glial cytoplasmic inclusions (GCIs), which are pathological hallmarks of idiopathic Parkinson's disease (IPD) and multiple system atrophy (MSA). Initiating factors that culminate in forming LBs/LNs/GCIs remain elusive. Several species of α-synuclein exist, including phosphorylated and nitrated forms. It is unclear which α-synuclein post-translational modifications (PTMs) appear within aggregates throughout disease pathology. Herein we aimed to establish the predominant α-synuclein PTMs in postmortem IPD and MSA pathology using immunohistochemistry. We examined the patterns of three α-synuclein PTMs (pS87, pS129, nY39) simultaneously in pathology-affected regions of 15 IPD cases, 5 MSA cases, and 6 neurologically normal controls. All antibodies recognized LBs, LNs, and GCIs, albeit to a variable extent. pS129 α-synuclein antibody was particularly immunopositive for LNs and synaptic dot-like structures, followed by nY39 α-synuclein antibody. GCIs, neuronal inclusions, and small threads were positive for nY39 α-synuclein in MSA. Quantification of the LB scores revealed that pS129 α-synuclein was the dominant and earliest α-synuclein PTM, followed by nY39 α-synuclein, while lower amounts of pSer87 α-synuclein appeared later in disease progression in PD. These results may have implications for novel biomarker and therapeutic developments.

Topics: alpha-Synuclein; Antibodies; Humans; Inclusion Bodies; Lewy Bodies; Multiple System Atrophy; Parkinson Disease

Finding an easily accessible and reliable tool to diagnose the diseases collectively defined as 'synucleinopathies' is an urgent, unmet priority. The synucleinopathies include Parkinson's disease, multiple system atrophy, pure autonomic failure and dementia with Lewy bodies. There are millions of people who have a diagnosis of a synucleinopathy, with more diagnosed every year. With accessibility, ease of implementation, consistently high sensitivity (>80%) and specificity approaching 100%, skin biopsy has great potential as the clinical test of choice for the diagnosis of synucleinopathies. The large, multi-center Synuclein-One study will determine the sensitivity, specificity, accuracy and precision of α-synuclein detection within punch skin biopsies in patients with clinically established synucleinopathies using standardized, robust methods suitable for large-scale analysis. Clinical Trial Registration: NCT04700722 (ClinicalTrials.gov).

Topics: alpha-Synuclein; Biopsy; Humans; Multiple System Atrophy; Parkinson Disease; Synucleinopathies

Alpha-synucleinopathies (AS) are characterized by pathologic aggregations of alpha-synuclein (α-syn) in the central nervous system, and comprise dementia with Lewy bodies, Parkinson's disease, and multiple system atrophy. Previous studies on AS have reported findings of α-syn pathology in the peripheral nervous system of multiple organs, including the heart.. The aim of this study was to further investigate and confirm the presence of cardiac α-syn in AS compared to other major neurocognitive disorders in a neuropathologically confirmed cohort.. All deceased patients with performed autopsy and with neuropathologically confirmed AS at the Clinical Department of Pathology in Lund 2010-May 2021 were evaluated for inclusion. Cases with insufficiently sampled cardiac tissue or only limited neuropathological investigation were excluded. An age-matched group of individuals with other neurodegenerative diseases, having no α-syn in the CNS, served as controls. In total, 68 AS and 32 control cases were included in the study. Immunohistochemistry for detection of cardiac α-syn aggregates was performed.. The AS group had a significantly higher prevalence of cardiac α-syn pathology (p≤0.001) than the control group, 82% and 0%, respectively.. This study confirms the association between AS and the presence of cardiac α-syn in a neuropathologically confirmed cohort. This motivates further research on potential pathophysiological effects on cardiac function in AS patients.

Topics: alpha-Synuclein; Cadaver; Case-Control Studies; Humans; Lewy Body Disease; Multiple System Atrophy; Parkinson Disease; Synucleinopathies

Aggregation of α-synuclein (oligomeric α-syn) has been considered as the pathological hallmark of Parkinson's disease (PD) and multiple system atrophy (MSA). Studies showed oligomeric α-syn/total α-syn ratio was increased in the saliva of patients with PD, suggesting that seeding activity of salivary oligomeric α-syn may be a novel biomarker for the diagnosis of PD and MSA.. This study aimed to evaluate the diagnostic value of salivary α-syn seeding activity in patients with PD and MSA.. A total of 75 patients with PD, 18 patients with MSA, and 36 nonneurodegenerative healthy control subjects underwent salivary α-syn real-time quaking-induced conversion (RT-QuIC) assay.. Salivary α-syn RT-QuIC assay distinguished patients with PD with 76.0% sensitivity (95% confidence interval [CI], 66.1-85.9) and 94.4% specificity (95% CI, 86.6-100.0). RT-QuIC assay sensitivity reached 61.1% (95% CI, 36.2-86.1) in patients with MSA. No significant differences were observed in the diameter of salivary α-syn fibrils examined by electron microscopy and in thioflavin T fluorescence intensity of salivary α-syn fibrils detected by RT-QuIC assay between patients with PD and MSA. Notably, the lag phase of RT-QuIC assay from patients with PD was significantly shorter than that of patients with MSA, which might be clinically applicable to the discrimination between PD and MSA.. Salivary α-syn seeding activity may serve as a novel biomarker for the clinical diagnosis of PD and MSA.© 2022 International Parkinson and Movement Disorder Society © 2022 International Parkinson and Movement Disorder Society.

Topics: alpha-Synuclein; Biomarkers; Humans; Multiple System Atrophy; Parkinson Disease

Synucleinopathies encompass several neurodegenerative diseases, which include Parkinson's disease, dementia with Lewy bodies and multiple system atrophy. These diseases are characterized by the deposit of α-synuclein aggregates in intracellular inclusions in neurons and glial cells. Unlike Parkinson's disease and dementia with Lewy bodies, where aggregates are predominantly neuronal, multiple system atrophy is associated with α-synuclein cytoplasmic inclusions in oligodendrocytes. Glial cytoplasmic inclusions are the pathological hallmark of multiple system atrophy and are associated with neuroinflammation, modest demyelination and, ultimately, neurodegeneration. To evaluate the possible pathogenic role of glial cytoplasmic inclusions, we inoculated glial cytoplasmic inclusion-containing brain fractions obtained from multiple system atrophy patients into the striatum of non-human primates. After a 2-year in vivo phase, extensive histochemical and biochemical analyses were performed on the whole brain. We found loss of both nigral dopamine neurons and striatal medium spiny neurons, as well as loss of oligodendrocytes in the same regions, which are characteristics of multiple system atrophy. Furthermore, demyelination, neuroinflammation and α-synuclein pathology were also observed. These results show that the α-synuclein species in multiple system atrophy-derived glial cytoplasmic inclusions can induce a pathological process in non-human primates, including nigrostriatal and striatofugal neurodegeneration, oligodendroglial cell loss, synucleinopathy and gliosis. The present data pave the way for using this experimental model for MSA research and therapeutic development.

Topics: alpha-Synuclein; Animals; Brain; Demyelinating Diseases; Humans; Inclusion Bodies; Lewy Body Disease; Multiple System Atrophy; Parkinson Disease; Synucleinopathies

SignificanceOur results demonstrate the existence of early cellular pathways and network alterations in oligodendrocytes in the alpha-synucleinopathies Parkinson's disease and multiple system atrophy. They further reveal the involvement of an immune component triggered by alpha-synuclein protein, as well as a connection between (epi)genetic changes and immune reactivity in multiple system atrophy. The knowledge generated in this study could be used to devise novel therapeutic approaches to treat synucleinopathies.

Topics: alpha-Synuclein; Humans; Induced Pluripotent Stem Cells; Multiple System Atrophy; Oligodendroglia; Parkinson Disease; Synucleinopathies

The distinct neuropathological features of the different α-Synucleinopathies, as well as the diversity of the α-Synuclein (α-Syn) intracellular inclusion bodies observed in post mortem brain sections, are thought to reflect the strain diversity characterizing invasive α-Syn amyloids. However, this "one strain, one disease" view is still hypothetical, and to date, a possible disease-specific contribution of non-amyloid factors has not been ruled out. In Multiple System Atrophy (MSA), the buildup of α-Syn inclusions in oligodendrocytes seems to result from the terminal storage of α-Syn amyloid aggregates first pre-assembled in neurons. This assembly occurs at the level of neuronal cytoplasmic inclusions, and even earlier, within neuronal intranuclear inclusions (NIIs). Intriguingly, α-Syn NIIs are never observed in α-Synucleinopathies other than MSA, suggesting that these inclusions originate (i) from the unique molecular properties of the α-Syn fibril strains encountered in this disease, or alternatively, (ii) from other factors specifically dysregulated in MSA and driving the intranuclear fibrillization of α-Syn. We report the isolation and structural characterization of a synthetic human α-Syn fibril strain uniquely capable of seeding α-Syn fibrillization inside the nuclear compartment. In primary mouse cortical neurons, this strain provokes the buildup of NIIs with a remarkable morphology reminiscent of cat's eye marbles (see video abstract). These α-Syn inclusions form giant patterns made of one, two, or three lentiform beams that span the whole intranuclear volume, pushing apart the chromatin. The input fibrils are no longer detectable inside the NIIs, where they become dominated by the aggregation of endogenous α-Syn. In addition to its phosphorylation at S129, α-Syn forming the NIIs acquires an epitope antibody reactivity profile that indicates its organization into fibrils, and is associated with the classical markers of α-Syn pathology p62 and ubiquitin. NIIs are also observed in vivo after intracerebral injection of the fibril strain in mice. Our data thus show that the ability to seed NIIs is a strain property that is integrally encoded in the fibril supramolecular architecture. Upstream alterations of cellular mechanisms are not required. In contrast to the lentiform TDP-43 NIIs, which are observed in certain frontotemporal dementias and which are conditional upon GRN or VCP mutations, our data support the hypothesis that the presence of α-Syn

Topics: alpha-Synuclein; Amyloid; Animals; Brain; Intranuclear Inclusion Bodies; Mice; Multiple System Atrophy; Neurons; Synucleinopathies

α-synuclein (αSyn) is an intrinsically disordered protein which can undergo structural transformations, resulting in the formation of stable, insoluble fibrils. αSyn amyloid-type nucleation can be induced by misfolded 'seeds' serving as a conformational template, tantamount to the prion-like mechanism. Accumulation of αSyn inclusions is a key feature of dementia with Lewy bodies (DLB) and multiple system atrophy (MSA), and are found as additional pathology in Alzheimer's disease (AD) such as AD with amygdala predominant Lewy bodies (AD/ALB). While these disorders accumulate the same pathological protein, they exhibit heterogeneity in clinical and histological features; however, the mechanism(s) underlying this variability remains elusive. Accruing data from human autopsy studies, animal inoculation modeling, and in vitro characterization experiments, have lent credence to the hypothesis that conformational polymorphism of the αSyn amyloid-type fibril structure results in distinct "strains" with categorical infectivity traits. Herein, we directly compare the seeding abilities and outcome of human brain lysates from these diseases, as well as recombinant preformed human αSyn fibrils by the intracerebral inoculation of transgenic mice overexpressing either human wild-type αSyn or human αSyn with the familial A53T mutation. Our study has revealed that the initiating inoculum heavily dictates the phenotypic and pathological course of disease. Interestingly, we have also established relevant host-dependent distinctions between propagation profiles, including burden and spread of inclusion pathology throughout the neuroaxis, as well as severity of neurological symptoms. These findings provide compelling evidence supporting the hypothesis that diverse prion-type conformers may explain the variability seen in synucleinopathies.

Topics: alpha-Synuclein; Alzheimer Disease; Amyloid; Animals; Humans; Mice; Mice, Transgenic; Multiple System Atrophy; Prions; Synucleinopathies

Differential diagnosis between Parkinson's disease (PD) and atypical parkinsonisms (APs: multiple system atrophy[MSA], progressive supranuclear palsy[PSP], corticobasal degeneration[CBD]) remains challenging. Lately, cerebrospinal fluid (CSF) studies of neurofilament light-chain (NFL) and RT-QuIC of alpha-synuclein (α-SYN) have shown promise, but data on their combination with MRI measures is lacking.. (1) to assess the combined diagnostic ability of CSF RT-QuIC α-SYN, CSF NFL and midbrain/pons MRI planimetry in degenerative parkinsonisms; (2) to evaluate if biomarker-signatures relate to clinical diagnoses and whether or not unexpected findings can guide diagnostic revision.. We collected demographic and clinical data and set up α-SYN RT-QuIC at our lab in a cross-sectional cohort of 112 participants: 19 control subjects (CSs), 20PD, 37MSA, 23PSP, and 13CBD cases. We also determined CSF NFL by ELISA and, in 74 participants (10CSs, 9PD, 26MSA, 19PSP, 10CBD), automatized planimetric midbrain/pons areas from 3T-MRI.. Sensitivity of α-SYN RT-QuIC for PD was 75% increasing to 81% after revisiting clinical diagnoses with aid of biomarkers. Sensitivity for MSA was 12% but decreased to 9% with diagnostic revision. Specificities were 100% against CSs, and 89% against tauopathies raising to 91% with diagnostic revision. CSF NFL was significantly higher in APs. The combination of biomarkers yielded high diagnostic accuracy (PD vs. non-PD AUC = 0.983; MSA vs. non-MSA AUC = 0.933; tauopathies vs. non-tauopathies AUC = 0.924). Biomarkers-signatures fitted in most cases with clinical classification.. The combination of CSF NFL, CSF RT-QuIC α-SYN and midbrain/pons MRI measures showed high discriminant ability across all groups. Results opposite to expected can assist diagnostic reclassification.

Topics: alpha-Synuclein; Biomarkers; Cross-Sectional Studies; Humans; Mesencephalon; Multiple System Atrophy; Parkinson Disease; Parkinsonian Disorders; Pons; Tauopathies

Based on immunostainings and biochemical analyses, certain post-translationally modified alpha-synuclein (aSyn) variants, including C-terminally truncated (CTT) and Serine-129 phosphorylated (pSer129) aSyn, are proposed to be involved in the pathogenesis of synucleinopathies such as Parkinson's disease with (PDD) and without dementia (PD), dementia with Lewy bodies (DLB), and multiple system atrophy (MSA). However, quantitative information about aSyn proteoforms in the human brain in physiological and different pathological conditions is still limited. To address this, we generated sequential biochemical extracts of the substantia nigra, putamen and hippocampus from 28 donors diagnosed and neuropathologically-confirmed with different synucleinopathies (PD/PDD/DLB/MSA), as well as Alzheimer's disease, progressive supranuclear palsy, and aged normal subjects. The tissue extracts were used to build a reverse phase array including 65 aSyn antibodies for detection. In this multiplex approach, we observed increased immunoreactivity in donors with synucleinopathies compared to controls in detergent-insoluble fractions, mainly for antibodies against CT aSyn and pSer129 aSyn. In addition, despite of the restricted sample size, clustering analysis suggested disease-specific immunoreactivity signatures in patient groups with different synucleinopathies. We aimed to validate and quantify these findings using newly developed immunoassays towards total, 119 and 122 CTT, and pSer129 aSyn. In line with previous studies, we found that synucleinopathies shared an enrichment of post-translationally modified aSyn in detergent-insoluble fractions compared to the other analyzed groups. Our measurements allowed for a quantitative separation of PDD/DLB patients from other synucleinopathies based on higher detergent-insoluble pSer129 aSyn concentrations in the hippocampus. In addition, we found that MSA stood out due to enrichment of CTT and pSer129 aSyn also in the detergent-soluble fraction of the SN and putamen. Together, our results achieved by multiplexed and quantitative immunoassay-based approaches in human brain extracts of a limited sample set point to disease-specific biochemical aSyn proteoform profiles in distinct neurodegenerative disorders.

Topics: Aged; alpha-Synuclein; Brain; Detergents; Humans; Lewy Body Disease; Multiple System Atrophy; Synucleinopathies

Multiple-system trophy (MSA) and Parkinson's Disease (PD) are both progressive, neurodegenerative diseases characterized by neuropathological deposition of aggregated alpha-synuclein (αSyn). The causes behind this aggregation are still unknown. We have reported aberrancies in MSA and PD patients in naturally occurring autoantibodies (nAbs) against αSyn (anti-αSyn-nAbs), which are important partakers in anti-aggregatory processes, immune-mediated clearance, and anti-inflammatory functions. To elaborate further on the timeline of autoimmune aberrancies towards αSyn, we investigated here the Immunoglobulin (Ig) affinity profile and subclass composition (IgG-total, IgG1-4 and IgM) of anti-αSyn-nAbs in serum samples from prodromal (p) phases of MSA and PD. Using an electrochemiluminescence competition immunoassay, we confirmed that the repertoire of high-affinity anti-αSyn-nAbs is significantly reduced in pMSA and pPD. Further, we demonstrated that pPD had increased anti-αSyn IgG-total levels compared to pMSA and controls, concordant with increased anti-αSyn IgG1 levels in pPD. Anti-αSyn IgG2 and IgG4 levels were reduced in pMSA and pPD compared with controls, whereas anti-αSyn IgG3 levels were reduced in pMSA compared to pPD and controls. The results indicate that the impaired reactivity towards αSyn occurs prior to disease onset. The apparent lack of high-affinity anti-αSyn nAbs may result in reduced clearance of αSyn, leading to aggregation of the protein. Thus, this study provides novel insights into possible causes behind the pathogenesis in synucleinopathies such as MSA and PD.

Topics: alpha-Synuclein; Autoantibodies; Humans; Immunoglobulin G; Multiple System Atrophy; Parkinson Disease

Multiple system atrophy (MSA) has no definitive genetic or environmental (G-E) risk factors, and the integrated effect of these factors on MSA etiology remains unknown. This study was undertaken to investigate the integrated effect of G-E factors associated with MSA and its subtypes, MSA-P and MSA-C.. A consecutive case-control study was conducted at two medical centers, and the interactions between genotypes of five previously reported susceptible single nucleotide polymorphisms (SNPs; SNCA_rs3857059, SNCA_rs11931074, COQ2_rs148156462, EDN1_rs16872704, MAPT_rs9303521) and graded exposure (never, ever, current) of four environmental factors (smoking, alcohol, drinking well water, pesticide exposure) were analyzed by a stepwise logistic regression model.. A total of 207 MSA patients and 136 healthy controls were enrolled. In addition to SNP COQ2_rs148156462 (TT), MSA risk was correlated with G-E interactions, including COQ2_rs148156462 (Tc) × pesticide nonexposure, COQ2_rs148156462 (TT) × current smokers, SNCA_rs11931074 (tt) × alcohol nonusers, and SNCA_rs11931074 (GG) × well water nondrinkers (all p < 0.01), with an area under the receiver operating characteristic curve (AUC) of 0.804 (95% confidence interval [CI] = 0.671-0.847). Modulated risk of MSA-C, with MSA-P as a control, correlated with COQ2_rs148156462 (TT) × alcohol nondrinkers, SNCA_rs11931074 (GG) × well water ever drinkers, SNCA_rs11931074 (Gt) × well water never drinkers, and SNCA_rs3857059 (gg) × pesticide nonexposure (all p < 0.05), with an AUC of 0.749 (95% CI = 0.683-0.815).. Certain COQ2 and SNCA SNPs interact with common environmental factors to modulate MSA etiology and subtype disposition. The mechanisms underlying the observed correlation between G-E interactions and MSA etiopathogenesis warrant further investigation.

Topics: Alkyl and Aryl Transferases; alpha-Synuclein; Case-Control Studies; Genetic Predisposition to Disease; Humans; Multiple System Atrophy; Pesticides; Water

Synaptic dysfunction in Parkinson's disease is caused by propagation of pathogenic α-synuclein between neurons. Previously, in multiple system atrophy (MSA), pathologically characterised by ectopic deposition of abnormal α-synuclein predominantly in oligodendrocytes, we demonstrated that the occurrence of memory impairment was associated with the number of α-synuclein-positive neuronal cytoplasmic inclusions (NCIs) in the hippocampus. In the present study, we aimed to investigate how abnormal α-synuclein in the hippocampus can lead to memory impairment.. We performed pathological and biochemical analyses using a mouse model of adult-onset MSA and human cases (MSA, N = 25; Parkinson's disease, N = 3; Alzheimer's disease, N = 2; normal controls, N = 11). In addition, the MSA model mice were examined behaviourally and physiologically.. In the MSA model, inducible human α-synuclein was first expressed in oligodendrocytes and subsequently accumulated in the cytoplasm of excitatory hippocampal neurons (NCI-like structures) and their presynaptic nerve terminals with the development of memory impairment. α-Synuclein oligomers increased simultaneously in the hippocampus of the MSA model. Hippocampal dendritic spines also decreased in number, followed by suppression of long-term potentiation. Consistent with these findings obtained in the MSA model, post-mortem analysis of human MSA brain tissues showed that cases of MSA with memory impairment developed more NCIs in excitatory hippocampal neurons along with α-synuclein oligomers than those without.. Our results provide new insights into the role of α-synuclein oligomers as a possible pathological cause of memory impairment in MSA.

Topics: alpha-Synuclein; Brain; Humans; Inclusion Bodies; Multiple System Atrophy; Neurons; Parkinson Disease

Dysregulation of autophagy, one of the major processes through which abnormal proteins are degraded, is a cardinal feature of synucleinopathies, including Lewy body diseases [Parkinson's disease (PD) and dementia with Lewy bodies (DLB)] and multiple system atrophy (MSA), which are characterized by the presence of abnormal α-synuclein in neurons and glial cells. Although several research groups have reported that Rubicon family proteins can regulate autophagosome-lysosome fusion or positioning, little is known about their involvement in synucleinopathies. In the present study, by studying patients with PD (N = 8), DLB (N = 13), and MSA (N = 5) and controls (N = 16), we explored the involvement of Rubicon family proteins [Rubicon, Pacer and differentially expressed in FDCP8 (DEF8)] in synucleinopathies. Immunohistochemical analysis showed that not only brainstem-type Lewy bodies but also cortical Lewy bodies were immunoreactive for DEF8 in Lewy body diseases, whereas Rubicon and Pacer were detectable in only a few brainstem-type Lewy bodies in PD. Glial cytoplasmic inclusions in patients with MSA were not immunoreactive for Rubicon, Pacer or DEF8. Immunoblotting showed significantly increased protein levels of DEF8 in the substantia nigra and putamen of patients with PD and the temporal cortex of patients with DLB. In addition, the smear band of DEF8 appeared in the insoluble fraction where that of phosphorylated α-synuclein was detected. These findings indicate the involvement of DEF8 in the formation of Lewy bodies. Quantitative and qualitative alterations in DEF8 may reflect the dysregulation of autophagy in Lewy body diseases.

Topics: alpha-Synuclein; Autophagy; Brain; Humans; Intracellular Signaling Peptides and Proteins; Lewy Bodies; Lewy Body Disease; Multiple System Atrophy; Parkinson Disease; Synucleinopathies

Multiple system atrophy (MSA) is a progressive neurodegenerative disorder. The usefulness of biomarkers in diagnosing MSA has been recently reported, but few studies have investigated the correlations among cerebrospinal fluid (CSF) biomarkers or the relationship between CSF biomarkers and the clinical parameters of patients with MSA. Thus, this was the aim of our study.. We performed cross-sectional study of CSF biomarkers in 50 patients with MSA and 20 control subjects. Ten of the patients with MSA were longitudinally followed for a period of 2 ± 1 years (mean ± standard deviation) as a substudy. We quantified CSF biomarkers including α-synuclein (α-syn), β-amyloid42 (Aβ42), total tau (t-tau) and phosphorylated tau (p-tau), neurofilament light chain (NfL), and neuron-glia2 (NG2), and assessed their relationship with clinical parameters (clinical subtypes, motor symptoms, nonmotor symptoms, and disease progression).. The levels of CSF α-syn, Aβ42, and p-tau were significantly lower, while those of NfL were higher in the patients with MSA than in the control subjects. Importantly, we found the significant elevation of soluble NG2 in the CSF of patients with MSA. CSF NfL showed the optimal diagnostic performance for MSA with levels at baseline significantly associated with longitudinal motor progression. With the exception of t-tau, there were no differences in the levels of CSF biomarkers between the MSA-parkinsonism and MSA-cerebellar subtypes.. Our results suggest CSF levels of NG2 and NfL as possible diagnostic and prognostic biomarkers in MSA. Further study is necessary to validate these findings.

Topics: alpha-Synuclein; Amyloid beta-Peptides; Biomarkers; Cross-Sectional Studies; Humans; Intermediate Filaments; Multiple System Atrophy; Neuroglia; Neurons; tau Proteins

Multiple System Atrophy is a rare neurodegenerative disease with alpha-synuclein aggregation in glial cytoplasmic inclusions and either predominant olivopontocerebellar atrophy or striatonigral degeneration, leading to dysautonomia, parkinsonism, and cerebellar ataxia. One prior genome-wide association study in mainly clinically diagnosed patients with Multiple System Atrophy failed to identify genetic variants predisposing for the disease.. Since the clinical diagnosis of Multiple System Atrophy yields a high rate of misdiagnosis when compared to the neuropathological gold standard, we studied only autopsy-confirmed cases.. We studied common genetic variations in Multiple System Atrophy cases (N = 731) and controls (N = 2898).. The most strongly disease-associated markers were rs16859966 on chromosome 3, rs7013955 on chromosome 8, and rs116607983 on chromosome 4 with P-values below 5 × 10. Since mutations of ZIC1 and ZIC4 and paraneoplastic autoantibodies directed against ZIC4 are associated with severe cerebellar dysfunction, we conducted immunohistochemical analyses in brain tissue of the frontal cortex and the cerebellum from 24 Multiple System Atrophy patients. Strong immunohistochemical expression of ZIC4 was detected in a subset of neurons of the dentate nucleus in all healthy controls and in patients with striatonigral degeneration, whereas ZIC4-immunoreactive neurons were significantly reduced inpatients with olivopontocerebellar atrophy. These findings point to a potential ZIC4-mediated vulnerability of neurons in Multiple System Atrophy. © 2022 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

Topics: alpha-Synuclein; Autoantibodies; Autopsy; Genome-Wide Association Study; Humans; Multiple System Atrophy; Nerve Tissue Proteins; Olivopontocerebellar Atrophies; Striatonigral Degeneration; Transcription Factors

In multiple system atrophy (MSA), the protein α-synuclein misfolds into a prion conformation that self-templates and causes progressive neurodegeneration. While many point mutations in the α-synuclein gene, SNCA, have been identified as the cause of heritable Parkinson's disease (PD), none have been identified as causing MSA. To examine whether MSA prions can transmit disease to mice expressing wild-type (WT) human α-synuclein, we inoculated transgenic (Tg) mice denoted TgM20

Topics: alpha-Synuclein; Animals; Female; Humans; Inclusion Bodies; Male; Mice; Mice, Transgenic; Multiple System Atrophy; Prions

Topics: alpha-Synuclein; Humans; Multiple System Atrophy; Parkinson Disease

In the present study, real-time quaking-induced conversion (RT-QuIC) assay was used to evaluate pathologic alpha-synuclein (AS) seeding activity in formalin-fixed paraffin-embedded (FFPE) tissue from the gastrointestinal (GI) tract of Parkinson's disease (PD) patients.. This study was conducted in two parts: Part I. a preliminary autopsy study that included four autopsy-confirmed patients with synucleinopathy (2 PD, 1 dementia with Lewy bodies [DLB], and 1 multiple system atrophy [MSA]) and two normal autopsy controls. Frozen and FFPE tissues of the brain were obtained. Part II. a clinical case-control study that included 20 clinically diagnosed PD patients and matched controls. Surgically resected FFPE tissues from the upper and lower GI tracts were used. The RT-QuIC assay was performed to evaluate pathologic seed amplification using frozen or FFPE tissues. The presence or absence of AS aggregation was confirmed by conventional phosphorylated AS (pAS) immunohistochemistry (IHC).. In Part I, RT-QuIC assay showed pathologic AS amplification in frozen and FFPE brain tissues of PD and DLB patients, and FFPE stomach tissue of PD patients but not in the MSA patient and controls. In Part II, pathologic seeding activity was found in 10% (2/20) of the stomach tissues of clinical PD patients but in none of the matched controls. IHC showed pAS-positive staining in 55% of patients (11/20) and 15% of controls (3/20).. The present study results showed that the RT-QuIC assay using FFPE tissue of the GI tract was inadequate as a biomarker in PD.

Topics: alpha-Synuclein; Autopsy; Biomarkers; Case-Control Studies; Formaldehyde; Gastrointestinal Tract; Humans; Multiple System Atrophy; Parkinson Disease

Topics: alpha-Synuclein; Brain; Humans; Multiple System Atrophy; Synucleinopathies

Multiple system atrophy (MSA) is a sporadic neurodegenerative disorder pathologically characterized by the presence of glial cytoplasmic inclusions (GCIs). Some MSA patients exhibit motor deficits with accompanying cognitive impairment. Of note, some patients suffering from MSA with longer disease duration have AT8-positive signals, which correspond to phosphorylated tau (P-tau) at 202/205 (P-tau202/205). However, P-tau sites other than the AT8 antibody epitope antibody are less well studied. Here, we focused on the effect of α-synuclein (Syn) expression on the phosphorylation of tau in MSA model mice. Among the 6 kinds of antibodies against P-tau, we confirmed that antibodies against P-tau at 231 (P-tau231) were phospho-specific and found that P-tau231 level was increased in parallel with disease progression in MSA model mice. Additional studies of human brains revealed that P-tau231 was mainly expressed in the temporal cortex in MSA brains and that its expression level was significantly higher in MSA patients than in controls. Immunohistochemical analysis showed that anti-P-tau231-, but not AT8, antibodies mainly immunolabeled hippocampal CA2/3 pyramidal neurons, and some GCIs in MSA. These data suggest that P-tau231 occurs in MSA differently from P-tau202/205.

Topics: alpha-Synuclein; Animals; Antibodies; Epitopes; Humans; Immunohistochemistry; Mice; Multiple System Atrophy; Neuroglia; Phosphorylation; Threonine

Previous studies have shown that α-synuclein (α-syn) accumulation in the normal aging brain is associated with a parallel increase in hemoglobin-binding α-syn (Hb-α-syn) in the brain and peripheral erythrocytes (ERCs), indicating that Hb-α-syn levels in ERCs may reflect the α-syn changes in the brain. However, if there is any change in ERC Hb-α-syn levels in disease condition is unclear. In this study, Hb-α-syn levels in ERCs from 149 Patients with multiple system atrophy (MSA) and 149 healthy controls (HCs) were measured by enzyme linked immunosorbent assay (ELISA). The results showed that Hb-α-syn levels in ERCs were significantly increased in MSA patients in comparison with those in HCs (777.84 ± 240.82 ng/mg vs 508.84 ± 162.57 ng/mg, P < 0.001). Receiver operating characteristic curve (ROC) indicated that increased Hb-α-syn in ERCs could discriminate MSA patients from HCs, with a sensitivity of 71.8%, a specificity of 80.5%, and an area under the curve (AUC) of 0.837. The positive and negative predictive values at a cut-off value of 616.12 ng/mg were 78.7% and 74.1%, respectively. However, the increase in Hb-α-syn levels did not show any association with the age of onset and consultation, disease duration, and UMSARS (I-IV) score. This pilot study suggests that ERC Hb-α-syn is increased in MSA patients and could evaluate α-syn accumulation in the brain of patients.

Topics: alpha-Synuclein; Erythrocytes; Hemoglobins; Humans; Multiple System Atrophy; Parkinson Disease; Pilot Projects

Parkinson's disease (PD) and Multiple System Atrophy (MSA) are progressive and unremitting neurological diseases that are neuropathologically characterized by α-synuclein inclusions. Increasing evidence supports the aggregation of α-synuclein in specific brain areas early in the disease course, followed by the spreading of α-synuclein pathology to multiple brain regions. However, little is known about how the structure of α-synuclein fibrils influence its ability to seed endogenous α-synuclein in recipient cells. Here, we aggregated α-synuclein by seeding with homogenates of PD- and MSA-confirmed brain tissue, determined the resulting α-synuclein fibril structures by cryo-electron microscopy, and characterized their seeding potential in mouse primary oligodendroglial cultures. The combined analysis shows that the two patient material-amplified α-synuclein fibrils share a similar protofilament fold but differ in their inter-protofilament interface and their ability to recruit endogenous α-synuclein. Our study indicates that the quaternary structure of α-synuclein fibrils modulates the seeding of α-synuclein pathology inside recipient cells. It thus provides an important advance in the quest to understand the connection between the structure of α-synuclein fibrils, cellular seeding/spreading, and ultimately the clinical manifestations of different synucleinopathies.

Topics: alpha-Synuclein; Animals; Cryoelectron Microscopy; Mice; Multiple System Atrophy; Parkinson Disease; Synucleinopathies

The development of specific disease-associated PET tracers is one of the major challenges, the realization of which in neurodegenerative diseases would enable not only the efficiency of diagnosis but also support the development of disease-modifying therapeutics. Parkinson's disease (PD) is the most common neurodegenerative movement disorder and is characterized by neuronal fibrillary inclusions composed of aggregated α-synuclein (α-syn). However, these deposits are not only found in PD, but also in other related diseases such as multiple system atrophy (MSA) and dementia with Lewy bodies (DLB), which are grouped under the term synucleinopathies. In this study, we used NGS-guided phage display selection to identify short peptides that bind aggregated α-syn. By surface plasmon resonance (SPR)-based affinity screening, we identified the peptide SVLfib-5 that recognizes aggregated α-syn with high complex stability and sequence specificity. Further analysis SPR showed that SVLfib-5 is not only specific for aggregated α-syn, but in particular recognizes fibrillary and oligomeric structures. Moreover, fluorescence microscopy of human brain tissue sections from PD, MSA, and DLB patients with SVLfib-5 allowed specific recognition of α-syn and a clear discrimination between diseased and non-diseased samples. These findings provide the basis for the further development of an α-syn PET tracer for early diagnosis and monitoring of disease progression and therapy progress.

Topics: alpha-Synuclein; Brain; Humans; Lewy Body Disease; Multiple System Atrophy; Parkinson Disease

We aimed to investigate the frequency of multiple system atrophy (MSA) in a large number of forensic autopsies and characterize the pathological appearance of preclinical MSA. We investigated a series of 1930 brains from forensic autopsies. In addition to performing immunohistochemistry for phosphorylated α-synuclein, the levels of 3 autonomic nervous system markers (catecholaminergic, serotonergic, and cholinergic) were used to assess the peripheral nerve (heart and superior cervical ganglion) and medulla oblongata. The results were compared to those of healthy control and Parkinson disease (PD) cases. Four cases (0.21%) were identified as having MSA. Cases 1-3 were symptomatic, and Case 4 was incipient; that is, although no neuronal loss was evident, the cerebellar dentate nucleus exhibited marked grumose degeneration. Immunohistochemistry revealed a marked reduction in autonomic nervous system marker levels expressed in the medulla; this reduction was more prominent in the 3 symptomatic MSA cases than in the PD case. The opposite occurred for the peripheral nerve. Case 4 exhibited mild cholinergic nerve reduction. Two cases showed possible significant pathological changes in the heart. Grumose degeneration, few oligodendroglial cytoplasmic inclusions without neuronal loss, and less reduction of autonomic nervous tissue were more prominent in the preclinical case than in symptomatic cases.

Topics: alpha-Synuclein; Brain; Cholinergic Agents; Humans; Inclusion Bodies; Medulla Oblongata; Multiple System Atrophy

Alpha-synuclein (aSyn) is a pre-synaptic monomeric protein that can form aggregates in neurons in Parkinson's disease (PD), Parkinson's disease with dementia (PDD) and dementia with Lewy bodies (DLB), and in oligodendrocytes in multiple system atrophy (MSA). Although aSyn in astrocytes has previously been described in PD, PDD and DLB, the biochemical properties and topographical distribution of astrocytic aSyn have not been studied in detail. Here, we present a systematic investigation of aSyn astrocytic pathology using an expanded antibody toolset covering the entire sequence and key post-translational modifications (PTMs) of aSyn in Lewy body disorders (LBDs) and in MSA. Astrocytic aSyn was detected in the limbic cortical regions of LBDs but were absent in main pathological regions of MSA. The astrocytic aSyn was revealed only with antibodies against the mid N-terminal and non-amyloid component (NAC) regions covering aSyn residues 34-99. The astroglial accumulations were negative to canonical aSyn aggregation markers, including p62, ubiquitin and aSyn pS129, but positive for phosphorylated and nitrated forms of aSyn at Tyrosine 39 (Y39), and not resistant to proteinase K. Our findings suggest that astrocytic aSyn accumulations represent a major part of aSyn pathology in LBDs and possess a distinct sequence and PTM signature that is characterized by both N- and C-terminal truncations and modifications at Y39. This is the first description that aSyn accumulations are made solely from N- and C-terminally cleaved aSyn species and the first report demonstrating that astrocytic aSyn is a mixture of Y39 phosphorylated and nitrated species. These observations underscore the importance of systematic characterization of aSyn accumulations in different cell types to capture the aSyn pathological diversity in the brain. Our findings combined with further studies on the role of astrocytic pathology in the progression of LBDs can pave the way towards identifying novel disease mechanisms and therapeutic targets.

Topics: alpha-Synuclein; Astrocytes; Humans; Lewy Bodies; Lewy Body Disease; Multiple System Atrophy; Parkinson Disease; Protein Processing, Post-Translational; Synucleinopathies

The role of peripheral phosphorylated-α-Synuclein (p-α-syn) deposition on nerve degeneration in synucleinopathies is still unknown.. To assess the cutaneous neural distribution of p-α-Syn deposits and its correlation with clinical data and with morphology and function of cutaneous sensory and autonomic nerves in early Parkinson's disease (PD) and multiple system atrophy-parkinson type (MSA-p).. We recruited 57 PD (F/M = 21/36; age 63.5±9.4 years) and 43 MSA-p (F/M = 16/27; age 62.3±9.0 years) patients within 2 years from motor symptoms. We applied questionnaires and clinical scales, sensory thresholds, and sudomotor testing to assess severity of motor and non-motor involvement and sensory and autonomic dysfunction. We quantified, in skin biopsy from thigh, leg, and fingertip, epidermal, pilomotor, and sudomotor nerve fibers, Meissner corpuscles and intrapapillary myelinated endings and the neural distribution of p-α-syn deposits.. Compared to controls, we found a cutaneous denervation paralleling functional and clinical impairment. Sensory and autonomic denervation was more severe in MSA-p than in PD. Deposits of p-α-syn were found in the majority of patients, with no significant differences among sites in both groups. Higher occurrence of p-α-syn deposits in autonomic nerves differentiated (p < 0.01) PD from MSA-p. p-α-syn deposits correlated positively with sudomotor function, epidermal, pilomotor and sudomotor nerve densities, and inversely with non-motor symptoms and disease progression.. Our work demonstrated an early peripheral sensory and autonomic involvement in synucleinopathies, more severe in MSA-p than in PD. Higher p-α-syn deposits in autonomic nerves differentiated PD from MSA-p. p-α-syn deposits were associated with preserved innervation and slower disease progression.

Topics: Aged; alpha-Synuclein; Female; Humans; Male; Middle Aged; Multiple System Atrophy; Parkinson Disease; Parkinsonian Disorders; Skin; Synucleinopathies

Lipid peroxidation is a process of oxidative degradation of cellular lipids that is increasingly recognized as an important factor in the pathogenesis of neurodegenerative diseases. We were therefore interested in the manifestation of lipid peroxidation in synucleinopathies, a group of neurodegenerative diseases characterized by the central pathology of α-synuclein aggregates, including Parkinson's disease, multiple system atrophy, dementia with Lewy bodies and Alzheimer's disease with Lewy bodies. We assessed lipid peroxidation products, lipid aldehydes, in the amygdala, a common disease-affected region in synucleinopathies, and in the visual cortex, a disease-unaffected region. We found that the levels of lipid aldehydes were significantly increased in the amygdala, but not in the visual cortex. We hypothesized that these increases are due to increases in the abundance of unsaturated lipids, since lipid aldehydes are formed from unsaturated lipids. We undertook a comprehensive analysis of membrane lipids using liquid chromatography-mass spectrometry and found that unsaturated phosphatidylcholine, phosphatidylethanolamine, phosphatidylserine and sphingomyelin were specifically elevated in the amygdala and correlated with increases in lipid aldehydes. Furthermore, unsaturated phosphatidylethanolamine levels were associated with soluble α-synuclein. Put together, these results suggest that manifestation of lipid peroxidation is prevalent in synucleinopathies and is likely to be due to increases in unsaturated membrane lipids. Our findings underscore the importance of lipid peroxidation in α-synuclein pathology and in membrane structure maintenance.

Topics: Aldehydes; alpha-Synuclein; Brain; Humans; Lipid Peroxidation; Multiple System Atrophy; Phosphatidylethanolamines; Synucleinopathies

In multiple system atrophy (MSA), the α-synuclein protein misfolds into a self-templating prion conformation that spreads throughout the brain, leading to progressive neurodegeneration. While the E46K mutation in α-synuclein causes familial Parkinson's disease (PD), we previously discovered that this mutation blocks in vitro propagation of MSA prions. Recent studies by others indicate that α-synuclein adopts a misfolded conformation in MSA in which a Greek key motif is stabilized by an intramolecular salt bridge between residues E46 and K80. Hypothesizing that the E46K mutation impedes salt bridge formation and, therefore, exerts a selective pressure that can modulate α-synuclein strain propagation, we asked whether three distinct α-synuclein prion strains could propagate in TgM47+/- mice, which express human α-synuclein with the E46K mutation. Following intracranial injection of these strains, TgM47+/- mice were resistant to MSA prion transmission, whereas recombinant E46K preformed fibrils (PFFs) transmitted neurological disease to mice and induced the formation of phosphorylated α-synuclein neuropathology. In contrast, heterotypic seeding following wild-type (WT) PFF-inoculation resulted in preclinical α-synuclein prion propagation. Moreover, when we inoculated TgM20+/- mice, which express WT human α-synuclein, with E46K PFFs, we observed delayed transmission kinetics with an incomplete attack rate. These findings suggest that the E46K mutation constrains the number of α-synuclein prion conformations that can propagate in TgM47+/- mice, expanding our understanding of the selective pressures that impact α-synuclein prion replication.

Topics: alpha-Synuclein; Animals; Humans; Mice; Mice, Transgenic; Multiple System Atrophy; Mutation; Prions

Alpha-synuclein (aSyn) is a 14 kD protein encoded by the SNCA gene that is expressed in vertebrates and normally localizes to presynaptic terminals and the nucleus. aSyn forms pathological intracellular aggregates that typify a group of important neurodegenerative diseases called synucleinopathies. Previous work in human tissue and model systems indicates that some of these aggregates can be intranuclear, but the significance of aSyn aggregation within the nucleus is not clear. We used a mouse model that develops aggregated aSyn nuclear inclusions. Using aSyn preformed fibril injections in GFP-tagged aSyn transgenic mice, we were able to induce the formation of nuclear aSyn inclusions and study their properties in fixed tissue and in vivo using multiphoton microscopy. In addition, we analyzed human synucleinopathy patient tissue to better understand this pathology. Our data demonstrate that nuclear aSyn inclusions may form through the transmission of aSyn between neurons, and these intranuclear aggregates bear the hallmarks of cytoplasmic Lewy pathology. Neuronal nuclear aSyn inclusions can form rod-like structures that do not contain actin, excluding them from being previously described nuclear actin rods. Longitudinal, in vivo multiphoton imaging indicates that certain morphologies of neuronal nuclear aSyn inclusions predict cell death within 14 days. Human multiple system atrophy cases contain neurons and glia with similar nuclear inclusions, but we were unable to detect such inclusions in Lewy body dementia cases. This study suggests that the dysregulation of a nuclear aSyn function associated with nuclear inclusion formation could play a role in the forms of neurodegeneration associated with synucleinopathy.

Topics: Actins; alpha-Synuclein; Animals; Cell Death; Disease Models, Animal; Humans; Lewy Body Disease; Mice; Mice, Transgenic; Multiple System Atrophy; Synucleinopathies

The striatonigral and olivopontocerebellar systems are known to be vulnerable in multiple system atrophy (MSA), showing neuronal loss, astrogliosis, and alpha-synuclein-immunoreactive inclusions. MSA patients who displayed abundant neuronal cytoplasmic inclusions (NCIs) in the regions other than the striatonigral or olivopontocerebellar system have occasionally been diagnosed with variants of MSA. In this study, we report clinical and pathologic findings of MSA patients characterized by prominent pathologic involvement of the hippocampus. We assessed 146 consecutively autopsied MSA patients. Semi-quantitative analysis of anti-alpha-synuclein immunohistochemistry revealed that 12 of 146 patients (8.2%) had severe NCIs in two or more of the following areas: the hippocampal granule cells, cornu ammonis areas, parahippocampal gyrus, and amygdala. In contrast, the remaining 134 patients did not show severe NCIs in any of these regions. Patients with severe hippocampal involvement showed a higher representation of women (nine women/three men; Fisher's exact test, p = 0.0324), longer disease duration (13.1 ± 5.9 years; Mann-Whitney U-test, p = 0.000157), higher prevalence of cognitive impairment (four patients; Fisher's exact test, p = 0.0222), and lower brain weight (1070.3 ± 168.6 g; Mann-Whitney U-test, p = 0.00911) than other patients. The hippocampal granule cells and cornu ammonis area 1/subiculum almost always showed severe NCIs. The NCIs appeared to be ring-shaped or neurofibrillary tangle-like, fibrous configurations. Three of 12 patients also had dense, round-shaped NCIs that were morphologically similar to pick bodies. The patients with Pick body-like inclusions showed more severe atrophy of the medial temporal lobes and broader spreading of NCIs than those without. Immunohistochemistry for hyperphosphorylated tau and phosphorylated TDP-43 revealed minimal aggregations in the hippocampus of the hippocampal MSA patients. Our observations suggest a pathological variant of MSA that is characterized by severe involvement of hippocampal neurons. This phenotype may reinforce the importance of neuronal alpha-synucleinopathy in the pathogenesis of MSA.

Topics: alpha-Synuclein; Brain; Female; Hippocampus; Humans; Inclusion Bodies; Multiple System Atrophy; Neurons

Multiple system atrophy (MSA) is a fatal neurodegenerative disease where the histopathological hallmark is glial cytoplasmic inclusions in oligodendrocytes, rich of aggregated alpha-synuclein (aSyn). Therefore, therapies targeting aSyn aggregation and toxicity have been studied as a possible disease-modifying therapy for MSA. Our earlier studies show that inhibition of prolyl oligopeptidase (PREP) with KYP-2047 reduces aSyn aggregates in several models. Here, we tested the effects of KYP-2047 on a MSA cellular models, using rat OLN-AS7 and human MO3.13 oligodendrocyte cells. As translocation of p25α to cell cytosol has been identified as an inducer of aSyn aggregation in MSA models, the cells were transiently transfected with p25α. Similar to earlier studies, p25α increased aSyn phosphorylation and aggregation, and caused tubulin retraction and impaired autophagy in OLN-AS7 cells. In both cellular models, p25α transfection increased significantly aSyn mRNA levels and also increased the levels of inactive protein phosphatase 2A (PP2A). However, aSyn or p25α did not cause any cellular death in MO3.13 cells, questioning their use as a MSA model. Simultaneous administration of 10 µM KYP-2047 improved cell viability, decreased insoluble phosphorylated aSyn and normalized autophagy in OLN-AS7 cells but similar impact was not seen in MO3.13 cells.

Topics: alpha-Synuclein; Cell Line; Cell Survival; Humans; Multiple System Atrophy; Nerve Tissue Proteins; Oligodendroglia; Phosphorylation; Prolyl Oligopeptidases; Protein Aggregates; Protein Aggregation, Pathological

Pathways to control the spreading of α-synuclein (α-syn) and associated neuropathology in Parkinson's disease (PD), multiple system atrophy (MSA) and dementia with Lewy bodies (DLB) are unclear. Here, we show that preformed α-syn fibrils (PFF) increase the association between TLR2 and MyD88, resulting in microglial activation. The TLR2-interaction domain of MyD88 (wtTIDM) peptide-mediated selective inhibition of TLR2 reduces PFF-induced microglial inflammation in vitro. In PFF-seeded A53T mice, the nasal administration of the wtTIDM peptide, NEMO-binding domain (wtNBD) peptide, or genetic deletion of TLR2 reduces glial inflammation, decreases α-syn spreading, and protects dopaminergic neurons by inhibiting NF-κB. In summary, α-syn spreading depends on the TLR2/MyD88/NF-κB pathway and it can be reduced by nasal delivery of wtTIDM and wtNBD peptides.

Topics: alpha-Synuclein; Animals; Cells, Cultured; Disease Models, Animal; Dopaminergic Neurons; Humans; Lewy Body Disease; Mice; Mice, Knockout; Microglia; Multiple System Atrophy; Mutagenesis, Site-Directed; Mutation; Myeloid Differentiation Factor 88; NF-kappa B; Parkinson Disease; Primary Cell Culture; Promoter Regions, Genetic; Signal Transduction; Toll-Like Receptor 2

Multiple System Atrophy (MSA) is a rare neurodegenerative synucleinopathy which leads to severe disability followed by death within 6-9 years of symptom onset. There is compelling evidence suggesting that biological trace metals like iron and copper play an important role in synucleinopathies like Parkinson's disease and removing excess brain iron using chelators could slow down the disease progression. In human MSA, there is evidence of increased iron in affected brain regions, but role of iron and therapeutic efficacy of iron-lowering drugs in pre-clinical models of MSA have not been studied. We studied age-related changes in iron metabolism in different brain regions of the PLP-αsyn mice and tested whether iron-lowering drugs could alleviate disease phenotype in aged PLP-αsyn mice. Iron content, iron-ferritin association, ferritin protein levels and copper-ceruloplasmin association were measured in prefrontal cortex, putamen, substantia nigra and cerebellum of 3, 8, and 20-month-old PLP-αsyn and age-matched non-transgenic mice. Moreover, 12-month-old PLP-αsyn mice were administered deferiprone or ceruloplasmin or vehicle for 2 months. At the end of treatment period, motor testing and stereological analyses were performed. We found iron accumulation and perturbed iron-ferritin interaction in substantia nigra, putamen and cerebellum of aged PLP-αsyn mice. Furthermore, we found significant reduction in ceruloplasmin-bound copper in substantia nigra and cerebellum of the PLP-αsyn mice. Both deferiprone and ceruloplasmin prevented decline in motor performance in aged PLP-αsyn mice and were associated with higher neuronal survival and reduced density of α-synuclein aggregates in substantia nigra. This is the first study to report brain iron accumulation in a mouse model of MSA. Our results indicate that elevated iron in MSA mice may result from ceruloplasmin dysfunction and provide evidence that targeting iron in MSA could be a viable therapeutic option.

Topics: alpha-Synuclein; Animals; Brain; Cerebellum; Ceruloplasmin; Copper; Deferiprone; Disease Models, Animal; Ferritins; Iron; Iron Chelating Agents; Mice; Mice, Transgenic; Multiple System Atrophy; Prefrontal Cortex; Putamen; Substantia Nigra

Peripheral administration (oral, intranasal, intraperitoneal, intravenous) of assembled A53T α-synuclein induced synucleinopathy in heterozygous mice transgenic for human mutant A53T α-synuclein (line M83). The same was the case when cerebellar extracts from a case of multiple system atrophy with type II α-synuclein filaments were administered intraperitoneally, intravenously or intramuscularly. We observed abundant immunoreactivity for pS129 α-synuclein in nerve cells and severe motor impairment, resulting in hindlimb paralysis and shortened lifespan. Filaments immunoreactive for pS129 α-synuclein were in evidence. A 70% loss of motor neurons was present five months after an intraperitoneal injection of assembled A53T α-synuclein or cerebellar extract with type II α-synuclein filaments from an individual with a neuropathologically confirmed diagnosis of multiple system atrophy. Microglial cells changed from a predominantly ramified to a dystrophic appearance. Taken together, these findings establish a close relationship between the formation of α-synuclein inclusions in nerve cells and neurodegeneration, accompanied by a shift in microglial cell morphology. Propagation of α-synuclein inclusions depended on the characteristics of both seeds and transgenically expressed protein.

Topics: Aged; alpha-Synuclein; Animals; Animals, Genetically Modified; Hindlimb; Humans; Immunohistochemistry; Male; Mice, Neurologic Mutants; Microglia; Motor Neurons; Movement Disorders; Multiple System Atrophy; Mutation; Neurodegenerative Diseases; Neurons; Paralysis

Detection of the pathological and disease-associated alpha-synuclein (αSyn. OM samples were prospectively collected from patients with a probable diagnosis of MSA-P (n = 20, mean disease duration 4.4 years), MSA-C (n = 10, mean disease duration 4 years), PD (n = 13, mean disease duration 8 years), and healthy control subjects (HS) (n = 11). Each sample was analyzed by αSyn_RT-QuIC in two independent specialized laboratories, one located in Italy (ITA-lab) and one located in the USA (USA-lab). Both laboratories have developed and used harmonized αSyn_RT-QuIC analytical procedures. Results were correlated with demographic and clinical data.. The αSyn_RT-QuIC analysis reached a 96% interrater agreement of results (IAR) between laboratories (Kappa = 0.93, 95% CI 0.83-1.00). In particular, αSyn_RT-QuIC seeding activity was found in the OM of 9/13 patients with PD (sensitivity 69%, IAR 100%) and 18/20 patients with MSA-P (sensitivity 90%, IAR 100%). Interestingly, samples collected from patients with MSA-C did not induce αSyn_RT-QuIC seeding activity, except for one subject in USA-lab. Therefore, we found that MSA-P and MSA-C induced opposite effects. Regardless of disease diagnosis, the αSyn_RT-QuIC seeding activity correlated with some clinical parameters, including the rigidity and postural instability.. Our study provides evidence that OM-αSyn

Topics: alpha-Synuclein; Humans; Laboratories; Multiple System Atrophy; Olfactory Mucosa; Parkinson Disease; Reproducibility of Results

Parkinson's disease (PD) and multiple system atrophy (MSA) are caused by two distinct strains of disease-associated α-synuclein (αSyn

Topics: alpha-Synuclein; Cell Differentiation; Cell Line, Tumor; Humans; Inflammation; Multiple System Atrophy; Neuroblastoma; Olfactory Mucosa; Parkinson Disease; Protein Aggregates; Recombinant Proteins

Parkinson's disease is the second most common neurodegenerative disease after Alzheimer's disease. The pathophysiology of Parkinson's disease is complex and imperfectly known. Primum movens is abnormal intra-neuronal accumulation of the protein α-synuclein, leading to metabolic disturbances and neurodegeneration. This abnormal accumulation of α-synuclein is also found in dementia with Lewy bodies and multiple system atrophy, which together with Parkinson's disease form the group of α-synucleinopathies. Well known by its motor signs (bradykinesia, rest tremor, cogwheel rigidity and gait disturbance), Parkinson's disease is above all a systemic disease composed of a myriad of non-motor symptoms (constipation, sense of smell disorders, rapid eye movement sleep behaviour disorders, genitourinary disorders…). These non-motor symptoms caused by accumulation and migration of α-synuclein deposits from the gut and the olfactory bulb to the central nervous system may precede motor signs by ten years and therefore be of interest for early diagnosis. Furthermore, non-motor symptoms have a poorer impact on quality of life than motor signs themselves. Therefore, understanding, recognition and management of non-motor symptoms are crucial in management of parkinsonian patient. In this paper, we offer an update on the main non-motor symptoms of Parkinson's disease, from their pathophysiology to their screening, ending with their management.

Topics: alpha-Synuclein; Early Diagnosis; Humans; Multiple System Atrophy; Parkinson Disease; Quality of Life

Multiple system atrophy (MSA) is a fatal neurodegenerative disease that belongs to the family of α-synucleinopathies. At post mortem examination, intracellular inclusions of misfolded α-synuclein are found in neurons and oligodendrocytes and are considered to play a significant role in the pathogenesis. However, the early steps of the disease process are unknown and difficult to study in tissue derived from end-stage disease.. Induced pluripotent stem cells (iPSCs) were generated from patients' and control skin fibroblasts and differentiated into NCAM-positive neural progenitor cells (NPCs). The mitochondrial morphology and function were assessed by immunocytochemistry and high resolution respirometry. The ability to cope with exogenous oxidative stress was tested by exposure to different doses of luperox. The expression of α-synuclein was studied by immunocytochemistry.. We identified increased tubulation of mitochondria with preserved respiration profile in MSA-derived NPCs. Exposure of these cells to exogenous oxidative stress even at low doses, triggered an excessive generation of reactive oxygen species (ROS) and cleavage of caspase-3. MSA-derived NPCs did not present changed levels of SNCA gene expression nor intracellular aggregates of α-synuclein. However, we identified disease-related translocation of α-synuclein to the nucleus.. Our results show early cellular dysfunction in MSA-derived NPCs. We identified changes in the redox homeostasis which are functionally compensated at baseline but cause increased susceptibility to exogenous oxidative stress. In addition, nuclear translocation of α-synuclein in MSA-derived NPCs supports an early cellular stress response which may precede the neurodegenerative process in this disorder.

Topics: alpha-Synuclein; Cells, Cultured; Humans; Induced Pluripotent Stem Cells; Mitochondria; Multiple System Atrophy; Neural Stem Cells; Oxidative Stress; Protein Transport

Multiple system atrophy (MSA) is a rare neurodegenerative disease characterized by intracellular accumulations of α-synuclein and nerve cell loss in striatonigral and olivopontocerebellar structures. Epidemiological and clinical studies have reported potential involvement of autoimmune mechanisms in MSA pathogenesis. However, genetic etiology of this interaction remains unknown. We aimed to investigate genetic overlap between MSA and 7 autoimmune diseases and to identify shared genetic loci.. Genome-wide association study summary statistics of MSA and 7 autoimmune diseases were combined in cross-trait conjunctional false discovery rate analysis to explore overlapping genetic background. Expression of selected candidate genes was compared in transgenic MSA mice and wild-type mice. Genetic variability of candidate genes was further investigated using independent whole-exome genotyping data from large cohorts of MSA and autoimmune disease patients and healthy controls.. We observed substantial polygenic overlap between MSA and inflammatory bowel disease and identified 3 shared genetic loci with leading variants upstream of the DENND1B and RSP04 genes, and in intron of the C7 gene. Further, the C7 gene showed significantly dysregulated expression in the degenerating midbrain of transgenic MSA mice compared with wild-type mice and had elevated burden of protein-coding variants in independent MSA and inflammatory bowel disease cohorts.. Our study provides evidence of shared genetic etiology between MSA and inflammatory bowel disease with an important role of the C7 gene in both phenotypes, with the implication of immune and gut dysfunction in MSA pathophysiology. © 2020 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

Topics: alpha-Synuclein; Animals; Genome-Wide Association Study; Humans; Inflammatory Bowel Diseases; Mice; Mice, Transgenic; Multiple System Atrophy

Multiple system atrophy (MSA) is a rare and extremely debilitating progressive neurodegenerative disease characterized by variable combinations of parkinsonism, cerebellar ataxia, dysautonomia, and pyramidal dysfunction. MSA is a unique synucleinopathy, in which alpha synuclein-rich aggregates are present in the cytoplasm of oligodendroglia. The precise origin of the alpha synuclein (aSyn) found in the glial cytoplasmic inclusions (GCIs) as well the mechanisms of neurodegeneration in MSA remain unclear. Despite this fact, cell and animal models of MSA rely on oligodendroglial overexpression of aSyn. In the present study, we utilized a novel oligotrophic AAV, Olig001, to overexpress aSyn specifically in striatal oligodendrocytes of rats and nonhuman primates in an effort to further characterize our novel viral vector-mediated MSA animal models. Using two cohorts of animals with 10-fold differences in Olig001 vector titers, we show a dose-dependent formation of MSA-like pathology in rats. High titer of Olig001-aSyn in these animals were required to produce the formation of pS129+ and proteinase K resistant aSyn-rich GCIs, demyelination, and neurodegeneration. Using this knowledge, we injected high titer Olig001 in the putamen of cynomolgus macaques. After six months, histological analysis showed that oligodendroglial overexpression of aSyn resulted in the formation of hallmark GCIs throughout the putamen, demyelination, a 44% reduction of striatal neurons and a 12% loss of nigral neurons. Furthermore, a robust inflammatory response similar to MSA was produced in Olig001-aSyn NHPs, including microglial activation, astrogliosis, and a robust infiltration of T cells into the CNS. Taken together, oligodendroglial-specific viral vector-mediated overexpression of aSyn in rats and nonhuman primates faithfully reproduces many of the pathological disease hallmarks found in MSA. Future studies utilizing these large animal models of MSA would prove extremely valuable as a pre-clinical platform to test novel therapeutics that are so desperately needed for MSA.

Topics: alpha-Synuclein; Animals; Dependovirus; Disease Models, Animal; Genetic Vectors; Humans; Macaca fascicularis; Multiple System Atrophy; Neostriatum; Neurons; Oligodendroglia; Putamen; Rats; Stereotaxic Techniques

Multiple system atrophy (MSA) is a fatal neurodegenerative disease. Similar to Parkinson's disease (PD), MSA is an α-synucleinopathy, and its pathological hallmark consists of glial cytoplasmic inclusions (GCIs) containing α-synuclein (SNCA) in oligodendrocytes. We previously identified consistent changes in myelin-associated oligodendrocyte basic protein (MOBP) and huntingtin interacting protein 1 (HIP1) DNA methylation status in MSA. We hypothesized that if differential DNA methylation at these loci is mechanistically relevant for MSA, it should have downstream consequences on gene regulation.. We investigated the relationship between MOBP and HIP1 DNA methylation and mRNA levels in cerebellar white matter from MSA and healthy controls. Additionally, we analysed protein expression using western blotting, immunohistochemistry and proximity ligation assays.. We found decreased MOBP mRNA levels significantly correlated with increased DNA methylation in MSA. For HIP1, we found a distinct relationship between DNA methylation and gene expression levels in MSA compared to healthy controls, suggesting this locus may be subjected to epigenetic remodelling in MSA. Although soluble protein levels for MOBP and HIP1 in cerebellar white matter were not significantly different between MSA cases and controls, we found striking differences between MSA and other neurodegenerative diseases, including PD and Huntington's disease. We also found that MOBP and HIP1 are mislocalized into the GCIs in MSA, where they appear to interact with SNCA.. This study supports a role for DNA methylation in downregulation of MOBP mRNA in MSA. Most importantly, the identification of MOBP and HIP1 as new constituents of GCIs emphasizes the relevance of these two loci to the pathogenesis of MSA.

Topics: alpha-Synuclein; DNA-Binding Proteins; Humans; Inclusion Bodies; Multiple System Atrophy; Myelin Proteins; Neuroglia; Oligodendroglia; Parkinson Disease; White Matter

Topics: alpha-Synuclein; Autonomic Nervous System; Biomarkers; Humans; Lewy Body Disease; Multiple System Atrophy

The propagation of conformational strains by templated seeding is central to the prion concept. Seeded assembly of α-synuclein into filaments is believed to underlie the prion-like spreading of protein inclusions in a number of human neurodegenerative diseases, including Parkinson's disease, dementia with Lewy bodies (DLB) and multiple system atrophy (MSA). We previously determined the atomic structures of α-synuclein filaments from the putamen of five individuals with MSA. Here, we used filament preparations from three of these brains for the in vitro seeded assembly of recombinant human α-synuclein. We find that the structures of the seeded assemblies differ from those of the seeds, suggesting that additional, as yet unknown, factors play a role in the propagation of the seeds. Identification of these factors will be essential for understanding the prion-like spreading of α-synuclein proteinopathies.

Topics: alpha-Synuclein; Amyloid; Brain; Humans; Molecular Structure; Multiple System Atrophy; Protein Aggregates; Protein Aggregation, Pathological; Protein Binding; Protein Conformation

Multiple system atrophy (MSA) is a rare sporadic, progressive parkinsonism characterised by autonomic dysfunction. A recent genome-wide association study reported an association at the Elongation of Very Long Fatty Acids Protein 7 (ELOVL7) locus with MSA risk. In the current study four independent and unrelated cohorts were assessed, consisting of pathologically confirmed MSA cases, Parkinson's disease (PD) cases, and two unrelated, healthy control groups. All exons of ELOVL7 were sequenced in pathologically confirmed MSA cases; data for PPMI samples and Biobank controls was extracted from whole genome sequence. Coding variants in ELOVL7 were extremely rare, and we observed no significant association of ELOVL7 coding variants with risk of MSA.

Topics: Adult; Aged; Aged, 80 and over; alpha-Synuclein; Fatty Acid Elongases; Female; Genome-Wide Association Study; Humans; Male; Middle Aged; Multiple System Atrophy; Parkinson Disease; Polymorphism, Single Nucleotide

Pathological aggregates of alpha-synuclein in peripheral dermal nerve fibers can be detected in patients with idiopathic Parkinson's disease and multiple system atrophy. This study combines skin biopsy staining for p-alpha-synuclein depositions and radionuclide imaging of the heart with [

Topics: 3-Iodobenzylguanidine; Adult; Aged; alpha-Synuclein; Autonomic Fibers, Postganglionic; Female; Heart; Humans; Male; Middle Aged; Multiple System Atrophy; Nerve Fibers; Neural Conduction; Parkinson Disease; Peripheral Nervous System; Phosphorylation; Radionuclide Imaging; Radiopharmaceuticals; Skin

To determine whether (1) immunofluorescence is a reproducible technique in detecting misfolded α-synuclein in skin nerves and subsequently whether (2) immunofluorescence and real-time quaking-induced conversion (RT-QuIC) (both in skin and CSF) show a comparable in vivo diagnostic accuracy in distinguishing synucleinopathies from non-synucleinopathies in a large cohort of patients.. We prospectively recruited 90 patients fulfilling clinical and instrumental diagnostic criteria for all synucleinopathies variants and non-synucleinopathies (mainly including Alzheimer disease, tauopathies, and vascular parkinsonism or dementia). Twenty-four patients with mainly peripheral neuropathies were used as controls. Patients underwent skin biopsy for immunofluorescence and RT-QuIC; CSF was examined in patients who underwent lumbar puncture for diagnostic purposes. Immunofluorescence and RT-QuIC analysis were made blinded to the clinical diagnosis.. Immunofluorescence showed reproducible results between 2 pairs of neighboring skin samples. Both immunofluorescence and RT-QuIC showed high sensitivity and specificity in discriminating synucleinopathies from non-synucleinopathies and controls but immunofluorescence presented higher diagnostic accuracy. Immunofluorescence presented a good level of agreement with RT-QuIC in both skin and CSF in synucleinopathies.. Both immunofluorescence and RT-QuIC showed high diagnostic accuracy, although immunofluorescence displayed the better value as well as optimal reproducibility; they presented a good level of agreement in synucleinopathies, supporting the use of less invasive tests such as skin immunofluorescence or RT-QuIC instead of CSF RT-QuIC as a diagnostic tool for synucleinopathies.. This study provides Class III evidence that immunofluorescence or RT-QuIC accurately distinguish synucleinopathies from non-synucleinopathies.

Topics: Aged; alpha-Synuclein; Alzheimer Disease; Female; Fluorescent Antibody Technique; Humans; Lewy Body Disease; Male; Middle Aged; Multiple System Atrophy; Parkinson Disease; Parkinson Disease, Secondary; Peripheral Nerves; Protein Aggregates; Reproducibility of Results; Sensitivity and Specificity; Skin; Supranuclear Palsy, Progressive; Synucleinopathies; Tauopathies; TDP-43 Proteinopathies

Multiple system atrophy (MSA) is a rare, but fatal atypical parkinsonian disorder. The prototypical pathological hallmark are oligodendroglial cytoplasmic inclusions (GCIs) containing alpha-synuclein (α-syn). Currently, two MSA phenotypes are classified: the parkinsonian (MSA-P) and the cerebellar subtype (MSA-C), clinically characterized by predominant parkinsonism or cerebellar ataxia, respectively. Previous studies have shown that the transgenic MSA mouse model overexpressing human α-syn controlled by the oligodendroglial myelin basic protein (MBP) promoter (MBP29-hα-syn mice) mirrors crucial characteristics of the MSA-P subtype. However, it remains elusive, whether this model recapitulates important features of the MSA-C-related phenotype. First, we examined MSA-C-associated cerebellar pathology using human post-mortem tissue of MSA-C patients and controls. We observed the prototypical GCI pathology and a preserved number of oligodendrocytes in the cerebellar white matter (cbw) accompanied by severe myelin deficit, microgliosis, and a profound loss of Purkinje cells. Secondly, we phenotypically characterized MBP29-hα-syn mice using a dual approach: structural analysis of the hindbrain and functional assessment of gait. Matching the neuropathological features of MSA-C, GCI pathology within the cbw of MBP29-hα-syn mice was accompanied by a severe myelin deficit despite an increased number of oligodendrocytes and a high number of myeloid cells even at an early disease stage. Intriguingly, MBP29-hα-syn mice developed a significant loss of Purkinje cells at a more advanced disease stage. Catwalk XT gait analysis revealed decreased walking speed, increased stride length and width between hind paws. In addition, less dual diagonal support was observed toward more dual lateral and three paw support. Taken together, this wide-based and unsteady gait reflects cerebellar ataxia presumably linked to the cerebellar pathology in MBP29-hα-syn mice. In conclusion, the present study strongly supports the notion that the MBP29-hα-syn mouse model mimics important characteristics of the MSA-C subtype providing a powerful preclinical tool for evaluating future interventional strategies.

Topics: Aged; alpha-Synuclein; Animals; Cerebellar Ataxia; Cerebellum; Disease Models, Animal; Female; Humans; Male; Mice; Mice, Transgenic; Middle Aged; Multiple System Atrophy

The molecular architecture of α-Synuclein (α-Syn) inclusions, pathognomonic of various neurodegenerative disorders, remains unclear. α-Syn inclusions were long thought to consist mainly of α-Syn fibrils, but recent reports pointed to intracellular membranes as the major inclusion component. Here, we use cryo-electron tomography (cryo-ET) to image neuronal α-Syn inclusions in situ at molecular resolution. We show that inclusions seeded by α-Syn aggregates produced recombinantly or purified from patient brain consist of α-Syn fibrils crisscrossing a variety of cellular organelles. Using gold-labeled seeds, we find that aggregate seeding is predominantly mediated by small α-Syn fibrils, from which cytoplasmic fibrils grow unidirectionally. Detailed analysis of membrane interactions revealed that α-Syn fibrils do not contact membranes directly, and that α-Syn does not drive membrane clustering. Altogether, we conclusively demonstrate that neuronal α-Syn inclusions consist of α-Syn fibrils intermixed with membranous organelles, and illuminate the mechanism of aggregate seeding and cellular interaction.

Topics: alpha-Synuclein; Brain; Cryoelectron Microscopy; Humans; Inclusion Bodies; Multiple System Atrophy; Neurons

To explore the role of alpha-synuclein (αSyn) oligomers and neurofilament light chain (NfL) in cerebrospinal fluid (CSF) of patients with pure autonomic failure (PAF) as markers of future phenoconversion to multiple system atrophy (MSA).. Well-characterized patients with PAF (n = 32) were enrolled between June 2016 and February 2019 at Mayo Clinic Rochester and followed prospectively with annual visits to determine future phenoconversion to MSA, Parkinson's disease (PD), or dementia with Lewy bodies (DLB). ELISA was utilized to measure NfL and protein misfolding cyclic amplification (PMCA) to detect αSyn oligomers in CSF collected at baseline.. Patients were followed for a median of 3.9 years. Five patients converted to MSA, 2 to PD, and 2 to DLB. NfL at baseline was elevated only in patients who later developed MSA, perfectly separating those from future PD and DLB converters as well as non-converters. ASyn-PMCA was positive in all but two cases (94%). The PMCA reaction was markedly different in five samples with maximum fluorescence and reaction kinetics previously described in MSA patients; all of these patients later developed MSA.. αSyn-PMCA is almost invariably positive in the CSF of patients with PAF establishing this condition as α-synucleinopathy. Both NfL and the magnitude and reaction kinetics of αSyn PMCA faithfully predict which PAF patients will eventually phenoconvert to MSA. This finding has important implications not only for prognostication, but also for future trials of disease modifying therapies, allowing for differentiation of MSA from Lewy body synucleinopathies before motor symptoms develop. ANN NEUROL 2021;89:1212-1220.

Topics: Aged; alpha-Synuclein; Biomarkers; Disease Progression; Female; Humans; Lewy Body Disease; Longitudinal Studies; Male; Middle Aged; Multiple System Atrophy; Neurofilament Proteins; Parkinson Disease; Prospective Studies; Pure Autonomic Failure

Multiple system atrophy (MSA) is an insidious middle age-onset neurodegenerative disease that clinically presents with variable degrees of parkinsonism and cerebellar ataxia. The pathological hallmark of MSA is the progressive accumulation of glial cytoplasmic inclusions (GCIs) in oligodendrocytes that are comprised of α-synuclein (αSyn) aberrantly polymerized into fibrils. Experimentally, MSA brain samples display a high level of seeding activity to induce further αSyn aggregation by a prion-like conformational mechanism. Paradoxically, αSyn is predominantly a neuronal brain protein, with only marginal levels expressed in normal or diseased oligodendrocytes, and αSyn inclusions in other neurodegenerative diseases, including Parkinson's disease and Dementia with Lewy bodies, are primarily found in neurons. Although GCIs are the hallmark of MSA, using a series of new monoclonal antibodies targeting the carboxy-terminal region of αSyn, we demonstrate that neuronal αSyn pathology in MSA patient brains is remarkably abundant in the pontine nuclei and medullary inferior olivary nucleus. This neuronal αSyn pathology has distinct histological properties compared to GCIs, which allows it to remain concealed to many routine detection methods associated with altered biochemical properties of the carboxy-terminal domain of αSyn. We propose that these previously underappreciated sources of aberrant αSyn could serve as a pool of αSyn prion seeds that can initiate and continue to drive the pathogenesis of MSA.

Topics: Aged; Aged, 80 and over; alpha-Synuclein; Animals; Brain Stem; Female; Humans; Male; Mice; Mice, Inbred BALB C; Middle Aged; Multiple System Atrophy; Neurons

Pathology consisting of intracellular aggregates of alpha-Synuclein (α-Syn) spread through the nervous system in a variety of neurodegenerative disorders including Parkinson's disease, dementia with Lewy bodies, and multiple system atrophy. The discovery of structurally distinct α-Syn polymorphs, so-called strains, supports a hypothesis where strain-specific structures are templated into aggregates formed by native α-Syn. These distinct strains are hypothesised to dictate the spreading of pathology in the tissue and the cellular impact of the aggregates, thereby contributing to the variety of clinical phenotypes. Here, we present evidence of a novel α-Syn strain induced by the multiple system atrophy-associated oligodendroglial protein p25α. Using an array of biophysical, biochemical, cellular, and in vivo analyses, we demonstrate that compared to α-Syn alone, a substoichiometric concentration of p25α redirects α-Syn aggregation into a unique α-Syn/p25α strain with a different structure and enhanced in vivo prodegenerative properties. The α-Syn/p25α strain induced larger inclusions in human dopaminergic neurons. In vivo, intramuscular injection of preformed fibrils (PFF) of the α-Syn/p25α strain compared to α-Syn PFF resulted in a shortened life span and a distinct anatomical distribution of inclusion pathology in the brain of a human A53T transgenic (line M83) mouse. Investigation of α-Syn aggregates in brain stem extracts of end-stage mice demonstrated that the more aggressive phenotype of the α-Syn/p25α strain was associated with an increased load of α-Syn aggregates based on a Förster resonance energy transfer immunoassay and a reduced α-Syn aggregate seeding activity based on a protein misfolding cyclic amplification assay. When injected unilaterally into the striata of wild-type mice, the α-Syn/p25α strain resulted in a more-pronounced motoric phenotype than α-Syn PFF and exhibited a "tropism" for nigro-striatal neurons compared to α-Syn PFF. Overall, our data support a hypothesis whereby oligodendroglial p25α is responsible for generating a highly prodegenerative α-Syn strain in multiple system atrophy.

Topics: alpha-Synuclein; Animals; Cell Line; Humans; Inclusion Bodies; Mice; Mice, Transgenic; Multiple System Atrophy; Nerve Tissue Proteins; Neurodegenerative Diseases; Oligodendroglia; Protein Conformation; Proteostasis Deficiencies; Substantia Nigra; Synucleinopathies

The diagnosis of Parkinson's disease (PD) and atypical parkinsonian syndromes is difficult due to the lack of reliable, easily accessible biomarkers. Multiple system atrophy (MSA) is a synucleinopathy whose symptoms often overlap with PD. Exosomes isolated from blood by immunoprecipitation using CNS markers provide a window into the brain's biochemistry and may assist in distinguishing between PD and MSA. Thus, we asked whether α-synuclein (α-syn) in such exosomes could distinguish among healthy individuals, patients with PD, and patients with MSA. We isolated exosomes from the serum or plasma of these three groups by immunoprecipitation using neuronal and oligodendroglial markers in two independent cohorts and measured α-syn in these exosomes using an electrochemiluminescence ELISA. In both cohorts, α-syn concentrations were significantly lower in the control group and significantly higher in the MSA group compared to the PD group. The ratio between α-syn concentrations in putative oligodendroglial exosomes compared to putative neuronal exosomes was a particularly sensitive biomarker for distinguishing between PD and MSA. Combining this ratio with the α-syn concentration itself and the total exosome concentration, a multinomial logistic model trained on the discovery cohort separated PD from MSA with an AUC = 0.902, corresponding to 89.8% sensitivity and 86.0% specificity when applied to the independent validation cohort. The data demonstrate that a minimally invasive blood test measuring α-syn in blood exosomes immunoprecipitated using CNS markers can distinguish between patients with PD and patients with MSA with high sensitivity and specificity. Future optimization and validation of the data by other groups would allow this strategy to become a viable diagnostic test for synucleinopathies.

Topics: Adult; Aged; Aged, 80 and over; alpha-Synuclein; Area Under Curve; Biomarkers; Cohort Studies; Diagnosis, Differential; Enzyme-Linked Immunosorbent Assay; Exosomes; Female; Healthy Volunteers; Humans; Immunoprecipitation; Male; Middle Aged; Multiple System Atrophy; Neurons; Oligodendroglia; Parkinson Disease; Reproducibility of Results; Sensitivity and Specificity

Ubiquitous naturally occurring autoantibodies (nAbs) against alpha-synuclein (α-syn) may play important roles in the pathogenesis of Multiple System Atrophy (MSA) and Parkinson's disease (PD). Recently, we reported reduced high-affinity/avidity anti-α-syn nAbs levels in plasma from MSA and PD patients, along with distinct inter-group immunoglobulin (Ig)G subclass distributions. The extent to which these observations in plasma may reflect corresponding levels in the cerebrospinal fluid (CSF) is unknown.. Using competitive and indirect ELISAs, we investigated the affinity/avidity of CSF anti-α-syn nAbs as well as the CSF and plasma distribution of IgG subclasses and IgM nAbs in a cross-sectional cohort of MSA and PD patients.. Repertoires of high-affinity/avidity anti-α-syn IgG nAbs were reduced in CSF samples from MSA and PD patients compared to controls. Furthermore, anti-α-syn IgM nAb levels were relatively lower in CSF and plasma from MSA patients but were reduced only in plasma from PD patients. Interestingly, anti-α-syn IgG subclasses presented disease-specific profiles both in CSF and plasma. Anti-α-syn IgG1, IgG2 and IgG3 levels were relatively increased in CSF of MSA patients, whereas PD patients showed increased anti-α-syn IgG2 and reduced anti-α-syn IgG4 levels.. Differences in the plasma/CSF distribution of anti-α-syn nAbs seem to be a common feature of synucleinopathies. Our data add further support to the notion that MSA and PD patients may have compromised immune reactivity towards α-syn. The differing α-syn-specific systemic immunological responses may reflect their specific disease pathophysiologies. These results are encouraging for further investigation of these immunological mechanisms in neurodegenerative diseases.

Topics: Adult; Aged; Aged, 80 and over; alpha-Synuclein; Antibodies, Anti-Idiotypic; Autoantibodies; Biomarkers; Female; Humans; Male; Middle Aged; Multiple System Atrophy; Parkinson Disease

Differential diagnosis of Parkinson's disease (PD), multiple system atrophy (MSA) and progressive supranuclear paralysis (PSP) is challenging. This study aimed to investigate the expression of phosphorylated α-synuclein (p-α-syn) and phosphorylated tau-protein (p-tau) in sural nerves from patients with PD, MSA and PSP to find biomarkers for differential diagnosis. Clinical evaluations and sural nerve biopsies were performed on 8 PD patients, 8 MSA patients, 6 PSP patients and 8 controls (CTRs). Toluidine blue staining was used to observe morphological changes in sural nerves. The deposition of p-α-syn and p-tau was detected by immunohistochemistry with semiquantitative evaluation. Locations of p-α-syn and p-tau were identified by double immunofluorescent staining. In case groups, the density of nerve fibres decreased with swollen or fragmented Schwann cells (SCs). All cases (22/22) but no CTRs (0/8) presented p-α-syn immunoreactivity with gradually decreasing semiquantitative levels among the PD (6.00 ± 2.07), MSA (5.00 ± 2.33) and PSP (3.50 ± 1.52) groups. p-tau aggregates were found in 7/8 MSA (1.88 ± 1.46) and 6/6 PSP (1.67 ± 0.52) patients but not in PD patients or CTRs. There were different expression patterns of p-α-syn and p-tau in PD, MSA and PSP patients. These findings suggest that peripheral sensory nerve injury exists in PD, MSA and PSP patients. With a different expression pattern and level, p-α-syn and p-tau in sural nerves may serve as novel biomarkers for differential diagnosis of PD, MSA and PSP.

Topics: Aged; alpha-Synuclein; Biomarkers; Diagnosis, Differential; Humans; Middle Aged; Multiple System Atrophy; Parkinson Disease; Phosphorylation; Supranuclear Palsy, Progressive; Sural Nerve; tau Proteins

α-Synuclein (α-syn) is a major component of abnormal protein deposits observed in the brains of patients with synucleinopathies, including Parkinson's disease, dementia with Lewy bodies, and multiple system atrophy (MSA). The synaptic protein α-syn is water-soluble under normal physiological conditions, but in these patients' brains, we see accumulation of insoluble amyloid-like α-syn fibrils with prion-like properties. Intracerebral accumulation of these fibrils is correlated with disease onset and progression. Recombinant α-syn protein also forms amyloid-like fibrils that are structurally akin to those extracted from patients' brains. Recent cryo-electron microscopic studies have identified the core structures of synthetic α-syn fibrils and α-syn fibrils extracted from the brains of patients with MSA at the atomic level. In this chapter, we describe negative staining and immunoelectron microscopy protocols for ultrastructural characterization of synthetic α-syn fibrils and pathological α-syn fibrils.

Topics: alpha-Synuclein; Amyloid; Brain; Disease Progression; Humans; Microscopy, Electron; Microscopy, Immunoelectron; Multiple System Atrophy; Parkinson Disease; Recombinant Proteins

α-Synuclein is critical in the pathogenesis of Parkinson's disease and related disorders, yet it remains unclear how its aggregation causes degeneration of human dopaminergic neurons. In this study, we induced α-synuclein aggregation in human iPSC-derived dopaminergic neurons using fibrils generated de novo or amplified in the presence of brain homogenates from Parkinson's disease or multiple system atrophy. Increased α-synuclein monomer levels promote seeded aggregation in a dose and time-dependent manner, which is associated with a further increase in α-synuclein gene expression. Progressive neuronal death is observed with brain-amplified fibrils and reversed by reduction of intraneuronal α-synuclein abundance. We identified 56 proteins differentially interacting with aggregates triggered by brain-amplified fibrils, including evasion of Parkinson's disease-associated deglycase DJ-1. Knockout of DJ-1 in iPSC-derived dopaminergic neurons enhance fibril-induced aggregation and neuronal death. Taken together, our results show that the toxicity of α-synuclein strains depends on aggregate burden, which is determined by monomer levels and conformation which dictates differential interactomes. Our study demonstrates how Parkinson's disease-associated genes influence the phenotypic manifestation of strains in human neurons.

Topics: alpha-Synuclein; Brain; Cell Death; Dopaminergic Neurons; Humans; Induced Pluripotent Stem Cells; Multiple System Atrophy; Parkinson Disease; Phenotype; Protein Aggregates; Protein Aggregation, Pathological; Protein Conformation; Protein Deglycase DJ-1; Protein Interaction Mapping

The pathological hallmark of multiple system atrophy (MSA) is fibrillary aggregates of α-synuclein (α-Syn) in the cytoplasm and nucleus of both oligodendrocytes and neurons. In neurons, α-Syn localizes to the cytosolic and membrane compartments, including the synaptic vesicles, mitochondria, and endoplasmic reticulum (ER). α-Syn binds to vesicle-associated membrane protein-binding protein B (VAPB) in the ER membrane. Overexpression of wild-type and familial Parkinson's disease mutant α-Syn perturbs the association between the ER and mitochondria, leading to ER stress and ultimately neurodegeneration. We examined brains from MSA patients (n = 7) and control subjects (n = 5) using immunohistochemistry and immunoelectron microscopy with antibodies against VAPB and phosphorylated α-Syn. In controls, the cytoplasm of neurons and glial cells was positive for VAPB, whereas in MSA lesions VAPB immunoreactivity was decreased. The proportion of VAPB-negative neurons in the pontine nucleus was significantly higher in MSA (13.6%) than in controls (0.6%). The incidence of cytoplasmic inclusions in VAPB-negative neurons was significantly higher (42.2%) than that in VAPB-positive neurons (3.6%); 67.2% of inclusion-bearing oligodendrocytes and 51.1% of inclusion-containing neurons were negative for VAPB. Immunoelectron microscopy revealed that α-Syn and VAPB were localized to granulofilamentous structures in the cytoplasm of oligodendrocytes and neurons. Many vesicular structures labeled with anti-α-Syn were also observed within the granulofilamentous structures in the cytoplasm and nucleus of both oligodendrocytes and neurons. These findings suggest that, in MSA, reduction of VAPB is involved in the disease process and that vesicular structures are associated with inclusion formation.

Topics: Aged; Aged, 80 and over; alpha-Synuclein; Endoplasmic Reticulum Stress; Female; Humans; Inclusion Bodies; Male; Middle Aged; Mitochondria; Multiple System Atrophy; Neurons; Phosphorylation; Protein Aggregation, Pathological; Vesicular Transport Proteins

Multiple system atrophy (MSA) is a fatal neurodegenerative disorder characterized by aggregated α-synuclein (α-syn) in oligodendrocytes and accompanied by striatonigral and olivopontocerebellar degeneration and motor symptoms. Key features of MSA are replicated in the PLP-α-syn transgenic mouse, including progressive striatonigral degeneration and motor deterioration. There are currently no approved treatments for MSA. ATH434 is a novel, orally bioavailable brain penetrant small molecule inhibitor of α-syn aggregation.. To characterize ATH434 for disease modification in a mouse model of MSA.. Six-month-old PLP-α-syn mice (MSA mice) were ATH434-treated (ATH434 in food) or untreated (normal food) for 6 months. Motor behavior and numbers of nigral and striatal neurons were evaluated. α-syn aggregates and oligomers were quantified by immunohistochemical and western blot analyses. Microglial activation and neuroinflammation were assessed by histological and molecular analyses. Ferric iron in the Substantia nigra was evaluated with the Perls method.. ATH434-treated mice demonstrated preservation of motor performance in MSA mice that was associated with neuroprotection of nigral and striatal neurons. The rescue of the phenotype correlated with the reduction of α-syn inclusions and oligomers in animals receiving ATH434. ATH434-treated mice exhibited significantly increased lysosomal activity of microglia without increased pro-inflammatory markers, suggesting a role in α-syn clearing. ATH434-treatment was associated with lower intracellular nigral iron levels.. Our findings demonstrate the beneficial disease-modifying effect of ATH434 in oligodendroglial α-synucleinopathy on both the motor phenotype and neurodegenerative pathology in the PLP-α-syn transgenic mouse and support the development of ATH434 for MSA. © 2021 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

Topics: alpha-Synuclein; Animals; Disease Models, Animal; Mice; Mice, Transgenic; Multiple System Atrophy; Oligodendroglia

Objective diagnostic biomarkers are needed to support a clinical diagnosis.. 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).. 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.. 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.. 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.

Topics: alpha-Synuclein; Amyotrophic Lateral Sclerosis; Biomarkers; Frontotemporal Dementia; Humans; Multiple System Atrophy; tau Proteins

Synucleinopathies, including Parkinson's disease (PD), Lewy body dementia (LBD), Alzheimer's disease with amygdala restricted Lewy bodies (AD/ALB), and multiple system atrophy (MSA) comprise a spectrum of neurodegenerative disorders characterized by the presence of distinct pathological α-synuclein (αSyn) inclusions. Experimental and pathological studies support the notion that αSyn aggregates contribute to cellular demise and dysfunction with disease progression associated with a prion-like spread of αSyn aggregates via conformational templating. The initiating event(s) and factors that contribute to diverse forms of synucleinopathies remain poorly understood. A major post-translational modification of αSyn associated with pathological inclusions is a diverse array of specific truncations within the carboxy terminal region. While these modifications have been shown experimentally to induce and promote αSyn aggregation, little is known about their disease-, region- and cell type specific distribution. To this end, we generated a series of monoclonal antibodies specific to neo-epitopes in αSyn truncated after residues 103, 115, 119, 122, 125, and 129. Immunocytochemical investigations using these new tools revealed striking differences in the αSyn truncation pattern between different synucleinopathies, brain regions and specific cellular populations. In LBD, neuronal inclusions in the substantia nigra and amygdala were positive for αSyn cleaved after residues 103, 119, 122, and 125, but not 115. In contrast, in the same patients' brain αSyn cleaved at residue 115, as well as 103, 119 and 122 were abundant in the dorsal motor nucleus of the vagus. In patients with AD/ALB, these modifications were only weakly or not detected in amygdala αSyn inclusions. αSyn truncated at residues 103, 115, 119, and 125 was readily present in MSA glial cytoplasmic inclusions, but 122 cleaved αSyn was only weakly or not present. Conversely, MSA neuronal pathology in the pontine nuclei was strongly reactive to the αSyn x-122 neo-epitope but did not display any reactivity for αSyn 103 cleavage. These studies demonstrate significant disease-, region- and cell type specific differences in carboxy terminal αSyn processing associated with pathological inclusions that likely contributes to their distinct strain-like prion properties and promotes the diversity displayed in the degrees of these insidious diseases.

Topics: Aged; Aged, 80 and over; alpha-Synuclein; Alzheimer Disease; Amygdala; Antibodies, Monoclonal; Epitopes; Female; Humans; Lewy Body Disease; Male; Middle Aged; Multiple System Atrophy; Synucleinopathies; Temporal Lobe

Multiple system atrophy (MSA) is a fatal late-onset neurodegenerative disease. Although presenting with distinct pathological hallmarks, which in MSA consist of glial cytoplasmic inclusions (GCIs) containing fibrillar α-synuclein in oligodendrocytes, both MSA and Parkinson's disease are α-synucleinopathies. Pathologically, MSA can be categorized into striatonigral degeneration (SND), olivopontocerebellar atrophy (OPCA) or mixed subtypes. Despite extensive research, the regional vulnerability of the brain to MSA pathology remains poorly understood. Genetic, epigenetic and environmental factors have been proposed to explain which brain regions are affected by MSA, and to what extent. Here, we explored for the first time epigenetic changes in post-mortem brain tissue from MSA cases. We conducted a case-control study, and profiled DNA methylation in white mater from three brain regions characterized by severe-to-mild GCIs burden in the MSA mixed subtype (cerebellum, frontal lobe and occipital lobe). Our genome-wide approach using Illumina MethylationEPIC arrays and a powerful cross-region analysis identified 157 CpG sites and 79 genomic regions where DNA methylation was significantly altered in the MSA mixed-subtype cases. HIP1, LMAN2 and MOBP were amongst the most differentially methylated loci. We replicated these findings in an independent cohort and further demonstrated that DNA methylation profiles were perturbed in MSA mixed subtype, and also to variable degrees in the other pathological subtypes (OPCA and SND). Finally, our co-methylation network analysis revealed several molecular signatures (modules) significantly associated with MSA (disease status and pathological subtypes), and with neurodegeneration in the cerebellum. Importantly, the co-methylation module having the strongest association with MSA included a CpG in SNCA, the gene encoding α-synuclein. Altogether, our results provide the first evidence for DNA methylation changes contributing to the molecular processes altered in MSA, some of which are shared with other neurodegenerative diseases, and highlight potential novel routes for diagnosis and therapeutic interventions.

Topics: Aged; alpha-Synuclein; Brain; Case-Control Studies; DNA Methylation; DNA-Binding Proteins; Female; Gene Expression Profiling; Humans; Male; Mannose-Binding Lectins; Membrane Transport Proteins; Middle Aged; Multiple System Atrophy; Myelin Proteins; White Matter

Multiple system atrophy (MSA) is a fatal disorder with no effective treatment. MSA pathology is characterized by α-synuclein (aSyn) accumulation in oligodendrocytes, the myelinating glial cells of the central nervous system (CNS). aSyn accumulation in oligodendrocytes forms the pathognomonic glial cytoplasmic inclusions (GCIs) of MSA. MSA aSyn pathology is also associated with motor and autonomic dysfunction, including an impaired ability to sweat. MSA patients have abnormal CNS expression of glial-cell-line-derived neurotrophic factor (GDNF) and brain-derived neurotrophic factor (BDNF). Our prior studies using the parent compound FTY720, a food and drug administration (FDA) approved immunosuppressive for multiple sclerosis, reveal that FTY720 protects parkinsonian mice by increasing BDNF. Our FTY720-derivative, FTY720-Mitoxy, is known to increase expression of oligodendrocyte BDNF, GDNF, and nerve growth factor (NGF) but does not reduce levels of circulating lymphocytes as it is not phosphorylated so cannot modulate sphingosine 1 phosphate receptors (S1PRs). To preclinically assess FTY720-Mitoxy for MSA, we used mice expressing human aSyn in oligodendrocytes under a 2,' 3'-cyclic nucleotide 3'-phosphodiesterase (CNP) promoter. CNP-aSyn transgenic (Tg) mice develop motor dysfunction between 7 and 9 mo, and progressive GCI pathology. Using liquid chromatography-mass spectrometry (LC-MS/MS) and enzymatic assays, we confirmed that FTY720-Mitoxy was stable and active. Vehicle or FTY720-Mitoxy (1.1 mg/kg/day) was delivered to wild type (WT) or Tg littermates from 8.5-11.5 mo by osmotic pump. We behaviorally assessed their movement by rotarod and sweat production by starch‑iodine test. Postmortem tissues were evaluated by qPCR for BDNF, GDNF, NGF and GDNF-receptor RET mRNA and for aSyn, BDNF, GDNF, and Iba1 protein by immunoblot. MicroRNAs (miRNAs) were also assessed by qPCR. FTY720-Mitoxy normalized movement, sweat function and soleus muscle mass in 11.5 mo Tg MSA mice. FTY720-Mitoxy also increased levels of brain GDNF and reduced brain miR-96-5p, a miRNA that acts to decrease GDNF expression. Moreover, FTY720-Mitoxy blocked aSyn pathology measured by sequential protein extraction and immunoblot, and microglial activation assessed by immunohistochemistry and immunoblot. In the 3-nitropropionic acid (3NP) toxin model of MSA, FTY720-Mitoxy protected movement and mitochondria in WT and CNP-aSyn Tg littermates. Our data confirm potent in vivo protection by FTY720-

Topics: alpha-Synuclein; Animals; Behavior, Animal; Disease Models, Animal; Female; Fingolimod Hydrochloride; Gene Expression Regulation; Glial Cell Line-Derived Neurotrophic Factor; Humans; Inflammation; Male; Mice; Mice, Transgenic; MicroRNAs; Multiple System Atrophy; Neuroprotective Agents; Proto-Oncogene Proteins c-ret

Pre-clinical studies in models of multiple sclerosis and other inflammatory disorders suggest that high-salt diet may induce activation of the immune system and potentiate inflammation. However, high-salt diet constitutes a common non-pharmacological intervention to treat autonomic problems in synucleinopathies such as Parkinson's disease and multiple system atrophy. Since neuroinflammation plays an important pathogenic role in these neurodegenerative disorders, we asked here whether high-salt diet may aggravate the disease phenotype in a transgenic model of multiple system atrophy.. Nine-month-old PLP-hαSyn and matched wildtype mice received normal or high-salt diet for a period of 3 months. Behavioral, histological, and molecular analyses were performed to evaluate the effect of high-salt diet on motor decline, neuroinflammation, neurodegeneration, and α-synuclein accumulation in these mice.. Brain subregion-specific molecular and histological analyses showed no deleterious effects of high-salt diet on the level of microglial activation. Moreover, neuroinflammation-related cytokines and chemokines, T cell recruitment or astrogliosis were unaffected by high-salt diet exposure. Behavioral testing showed no effect of diet on motor decline. High-salt diet was not related to the deterioration of neurodegeneration or α-synuclein accumulation in PLP-hαSyn mice.. Here, we demonstrate that high-salt diet does not aggravate neuroinflammation and neurodegeneration in PLP-hαSyn mice. Our findings discard a deleterious pro-neuroinflammatory effect of high-salt diet in multiple system atrophy.

Topics: alpha-Synuclein; Animals; Brain; Disease Models, Animal; Humans; Inflammation; Mice; Mice, Inbred C57BL; Mice, Transgenic; Microglia; Multiple System Atrophy; Nerve Degeneration; Neurons; Sodium Chloride, Dietary

Multiple system atrophy (MSA), a progressive neurodegenerative disease characterized by autonomic dysfunction and motor impairment, is caused by the self-templated misfolding of the protein α-synuclein. With no treatment currently available, we sought to characterize the spread of α-synuclein in a transgenic mouse model of MSA prion propagation to support drug discovery programs for synucleinopathies. Brain homogenates from MSA patient samples or mouse-passaged MSA were inoculated either by standard freehand injection or stereotactically into TgM83+/- mice, which express human α-synuclein with the A53T mutation. Following disease onset, brains from the mice were tested for biologically active α-synuclein prions using a cell-based assay and examined for α-synuclein neuropathology. Inoculation studies using homogenates prepared from brain regions lacking detectable α-synuclein neuropathology transmitted neurological disease to mice. Terminal animals contained similar concentrations of α-synuclein prions; however, a time-course study where mice were terminated every five days through disease progression revealed that the kinetics of α-synuclein prion replication in the mice were variable. Stereotactic inoculation into the thalamus reduced variability in disease onset in the mice, although incubation times were consistent with standard inoculations. Using human samples with and without neuropathological lesions, we observed that α-synuclein prion formation precedes neuropathology in the brain, suggesting that disease in patients is not limited to brain regions containing neuropathological lesions.

Topics: alpha-Synuclein; Animals; Brain; Female; Humans; Kinetics; Male; Mice; Mice, Transgenic; Multiple System Atrophy; Point Mutation; Prions

Synucleinopathies are neurodegenerative diseases that are associated with the misfolding and aggregation of α-synuclein, including Parkinson's disease, dementia with Lewy bodies and multiple system atrophy

Topics: alpha-Synuclein; Amyloid; Brain Chemistry; Circular Dichroism; Endopeptidase K; Humans; Multiple System Atrophy; Parkinson Disease; Protein Conformation; Protein Denaturation; Protein Folding; Spectroscopy, Fourier Transform Infrared

REM sleep behavior disorder (RBD) can progress to Parkinson's disease, Lewy body dementia, or multiple system atrophy within 20 years of onset. Accurate diagnosis of RBD is therefore important for early intervention. The development of markers that can more sensitively evaluate the effects of high-risk groups or candidate therapies that develop α-synucleinopathy in the short term is the key to a successful clinical trial. Clinical protocols for early diagnosis of α-synucleinopathy are currently being developed. The next stage will be to conduct clinical trials for candidate therapies.

Topics: alpha-Synuclein; Biomarkers; Humans; Lewy Body Disease; Multiple System Atrophy; Parkinson Disease; REM Sleep Behavior Disorder; Synucleinopathies

Topics: alpha-Synuclein; Emotions; Humans; Multiple System Atrophy; Parkinson Disease

Topics: alpha-Synuclein; Humans; Multiple System Atrophy; Synucleinopathies

Fluorescent small molecules are powerful tools for imaging α-synuclein pathology in vitro and in vivo. In this work, we explore benzofuranone as a potential scaffold for the design of fluorescent α-synuclein probes. These compounds have high affinity for α-synuclein, show fluorescent turn-on upon binding to fibrils, and display different binding to Lewy bodies, Lewy neurites and glial cytoplasmic inclusion pathologies in post-mortem brain tissue. These studies not only reveal the potential of benzofuranone compounds as α-synuclein specific fluorescent probes, but also have implications for the ways in which α-synucleinopathies are conformationally different and display distinct small molecule binding sites.

Topics: alpha-Synuclein; Alzheimer Disease; Benzofurans; Fluorescence; Fluorescent Dyes; Humans; Microscopy, Fluorescence; Multiple System Atrophy; Parkinson Disease

Topics: alpha-Synuclein; Animals; Autonomic Nervous System; Biomarkers; Biomedical Research; Erythrocytes; Humans; Multiple System Atrophy; Wearable Electronic Devices

Topics: alpha-Synuclein; Cerebellum; Humans; Multiple System Atrophy; Probability

Topics: alpha-Synuclein; Cerebellum; Humans; Multiple System Atrophy; Parkinson Disease

Topics: alpha-Synuclein; Brain; Humans; Multiple System Atrophy; Parkinson Disease

Multiple system atrophy (MSA) is a rare, untreatable neurodegenerative disorder characterized by accumulation of α-synuclein in oligodendroglial inclusions. As such, MSA is a synucleinopathy along with Parkinson's disease (PD) and dementia with Lewy bodies. Activation of the abelson tyrosine kinase c-Abl leads to phosphorylation of α-synuclein at tyrosine 39, thereby promoting its aggregation and subsequent neurodegeneration. The c-Abl inhibitor nilotinib used for the treatment of chronic myeloid leukemia based on data collected in preclinical models of PD might interfere with pathogenic mechanisms that are relevant to PD and dementia with Lewy bodies, which motivated its assessment in an open-label clinical trial in PD and dementia with Lewy bodies patients. The objective of this study was to assess the preclinical efficacy of nilotinib in the specific context of MSA.. Mice expressing human wild-type α-synuclein in oligodendrocytes received daily injection of nilotinib (1 or 10 mg/kg) over 12 weeks. Postmortem analysis included the assessment of c-Abl activation, α-synuclein burden, and dopaminergic neurodegeneration.. α-Synuclein phosphorylated at tyrosine 39 was detected in glial cytoplasmic inclusions in MSA patients. Increased activation of c-Abl and α-synuclein phosphorylation at tyrosine 39 were found in transgenic mice. Despite significant inhibition of c-Abl and associated reduction of α-synuclein phosphorylation at tyrosine 39 by 40%, nilotinib failed to reduce α-synuclein aggregate burden (including phosphorylation at serine 129) in the striatum and cortex or to lessen neurodegeneration in the substantia nigra.. This preclinical study suggests that partial inhibition of c-Abl and reduction of α-synuclein phosphorylation at tyrosine 39 may not be a relevant target for MSA. © 2020 International Parkinson and Movement Disorder Society.

Topics: alpha-Synuclein; Animals; Brain; Humans; Mice; Multiple System Atrophy; Pyrimidines; Synucleinopathies

α-Synuclein is a naturally unfolded protein which easily aggregates and forms toxic inclusions and deposits. It is associated with several neurodegenerative diseases, including Parkinson's disease (PD), dementia with Lewy bodies (DLB), and multiple system atrophy (MSA). These diseases, called synucleinopathies, have overlapping symptoms but require different methods of treatment. There are no reliable approaches for early diagnoses of these diseases, and as a result, the treatment begins late, and the disorders are often misdiagnosed. Recent studies revealed that α-synuclein forms distinctive spatial structures or strains at the early steps of these diseases, which may be used for early diagnosis. One of these early diagnostic methods called PMCA (protein misfolding cyclic amplification) allows identification of the distinct α-synuclein strains specific for different human diseases. The method is successfully used for differential diagnosis of patients with PD and MSA.

Topics: alpha-Synuclein; Biomarkers; Diagnosis, Differential; Early Diagnosis; Humans; Lewy Body Disease; Multiple System Atrophy; Parkinson Disease; Protein Conformation; Protein Folding; Synucleinopathies

Multiple system atrophy (MSA) is a neurodegenerative disorder from α-synuclein aggregation. in vitro studies suggest vitamin B12 may interrupt α-synuclein-mediated neurodegeneration. The objective of this study was to determine whether serum vitamin B12 level at MSA diagnosis is associated with survival.. One hundred eighty-two MSA patients evaluated at Mayo Clinic with vitamin B12 testing were studied. We determined the risk of death in relationship to serum vitamin B12 levels at MSA diagnosis, adjusting for predictors of poor survival.. Predictors of shorter survival included vitamin B12 < 367 ng/L (HR, 1.8; 95% CI, 1.3-2.7), falls within 3 years of MSA diagnosis (HR, 1.6; 95% CI, 1.1-2.3), bladder symptoms (HR, 1.6; 95% CI, 1.0-2.6), urinary catheter requirement (HR, 1.7; 95% CI, 1.0-2.8), male sex (HR, 1.4; 95% CI, 1.0-2.0), and MSA-P subtype (HR, 1.5; 95% CI, 1.0-2.0).. Low vitamin B12 levels are associated with shorter survival in MSA. Additional studies to explore this observation and assess the potential role of vitamin B12 as a modifiable survival factor are needed. © 2020 International Parkinson and Movement Disorder Society.

Topics: alpha-Synuclein; Humans; Male; Multiple System Atrophy; Vitamin B 12

Synucleinopathies, such as Parkinson's disease (PD), multiple system atrophy (MSA), and dementia with Lewy bodies (DLB), are defined by the presence of α-synuclein (αSYN) aggregates throughout the nervous system but diverge from one another with regard to their clinical and pathological phenotype. The recent generation of pure fibrillar αSYN polymorphs with noticeable differences in structural and phenotypic traits has led to the hypothesis that different αSYN strains may be in part responsible for the heterogeneous nature of synucleinopathies. To further characterize distinct αSYN strains in the human brain, and establish a structure-pathology relationship, we pursued a detailed comparison of αSYN assemblies derived from well-stratified patients with distinct synucleinopathies. We exploited the capacity of αSYN aggregates found in the brain of patients suffering from PD, MSA or DLB to seed and template monomeric human αSYN in vitro via a protein misfolding cyclic amplification assay. A careful comparison of the properties of total brain homogenates and pure in vitro amplified αSYN fibrillar assemblies upon inoculation in cells and in the rat brain demonstrates that the intrinsic structure of αSYN fibrils dictates synucleinopathies characteristics. We report that MSA strains show several similarities with PD strains, but are significantly more potent in inducing motor deficits, nigrostriatal neurodegeneration, αSYN pathology, spreading, and inflammation, reflecting the aggressive nature of this disease. In contrast, DLB strains display no or only very modest neuropathological features under our experimental conditions. Collectively, our data demonstrate a specific signature for PD, MSA, and DLB-derived strains that differs from previously described recombinant strains, with MSA strains provoking the most aggressive phenotype and more similarities with PD compared to DLB strains.

Topics: Aged; Aged, 80 and over; alpha-Synuclein; Brain; Dementia; Female; Humans; Lewy Body Disease; Male; Middle Aged; Multiple System Atrophy; Parkinson Disease

Recent post-mortem studies reported 22-37% of patients with multiple system atrophy can develop cognitive impairment. With the aim of identifying associations between cognitive impairment including memory impairment and α-synuclein pathology, 148 consecutive patients with pathologically proven multiple system atrophy were reviewed. Among them, 118 (79.7%) were reported to have had normal cognition in life, whereas the remaining 30 (20.3%) developed cognitive impairment. Twelve of them had pure frontal-subcortical dysfunction, defined as the presence of executive dysfunction, impaired processing speed, personality change, disinhibition or stereotypy; six had pure memory impairment; and 12 had both types of impairment. Semi-quantitative analysis of neuronal cytoplasmic inclusions in the hippocampus and parahippocampus revealed a disease duration-related increase in neuronal cytoplasmic inclusions in the dentate gyrus and cornu ammonis regions 1 and 2 of patients with normal cognition. In contrast, such a correlation with disease duration was not found in patients with cognitive impairment. Compared to the patients with normal cognition, patients with memory impairment (pure memory impairment: n = 6; memory impairment + frontal-subcortical dysfunction: n = 12) had more neuronal cytoplasmic inclusions in the dentate gyrus, cornu ammonis regions 1-4 and entorhinal cortex. In the multiple system atrophy mixed pathological subgroup, which equally affects the striatonigral and olivopontocerebellar systems, patients with the same combination of memory impairment developed more neuronal inclusions in the dentate gyrus, cornu ammonis regions 1, 2 and 4, and the subiculum compared to patients with normal cognition. Using patients with normal cognition (n = 18), frontal-subcortical dysfunction (n = 12) and memory impairment + frontal-subcortical dysfunction (n = 18), we further investigated whether neuronal or glial cytoplasmic inclusions in the prefrontal, temporal and cingulate cortices or the underlying white matter might affect cognitive impairment in patients with multiple system atrophy. We also examined topographic correlates of frontal-subcortical dysfunction with other clinical symptoms. Although no differences in neuronal or glial cytoplasmic inclusions were identified between the groups in the regions examined, frontal release signs were found more commonly when patients developed frontal-subcortical dysfunction, indicating the involvement of the frontal-su

Topics: Adult; Aged; alpha-Synuclein; Bodily Secretions; Brain; Cognition; Cognitive Dysfunction; Dementia; Female; Hippocampus; Humans; Inclusion Bodies; Male; Memory; Memory Disorders; Middle Aged; Multiple System Atrophy; Neurons

Transportation of key proteins via extracellular vesicles has been recently implicated in various neurodegenerative disorders, including Parkinson's disease, as a new mechanism of disease spreading and a new source of biomarkers. Extracellular vesicles likely to be derived from the brain can be isolated from peripheral blood and have been reported to contain higher levels of α-synuclein (α-syn) in Parkinson's disease patients. However, very little is known about extracellular vesicles in multiple system atrophy, a disease that, like Parkinson's disease, involves pathological α-syn aggregation, though the process is centred around oligodendrocytes in multiple system atrophy. In this study, a novel immunocapture technology was developed to isolate blood CNPase-positive, oligodendrocyte-derived enriched microvesicles (OEMVs), followed by fluorescent nanoparticle tracking analysis and assessment of α-syn levels contained within the OEMVs. The results demonstrated that the concentrations of OEMVs were significantly lower in multiple system atrophy patients, compared to Parkinson's disease patients and healthy control subjects. It is also noted that the population of OEMVs involved was mainly in the size range closer to that of exosomes, and that the average α-syn concentrations (per vesicle) contained in these OEMVs were not significantly different among the three groups. The phenomenon of reduced OEMVs was again observed in a transgenic mouse model of multiple system atrophy and in primary oligodendrocyte cultures, and the mechanism involved was likely related, at least in part, to an α-syn-mediated interference in the interaction between syntaxin 4 and VAMP2, leading to the dysfunction of the SNARE complex. These results suggest that reduced OEMVs could be an important mechanism related to pathological α-syn aggregation in oligodendrocytes, and the OEMVs found in peripheral blood could be further explored for their potential as multiple system atrophy biomarkers.

Topics: Aged; alpha-Synuclein; Animals; Bodily Secretions; Brain; Cell-Derived Microparticles; Disease Models, Animal; Exosomes; Female; Humans; Male; Mice; Mice, Transgenic; Middle Aged; Multiple System Atrophy; Neurons; Oligodendroglia; Parkinson Disease; SNARE Proteins

Synucleinopathies, which include multiple system atrophy (MSA), Parkinson's disease, Parkinson's disease with dementia and dementia with Lewy bodies (DLB), are human neurodegenerative diseases

Topics: alpha-Synuclein; Brain; Cryoelectron Microscopy; Humans; Inclusion Bodies; Models, Molecular; Multiple System Atrophy; Protein Folding; Putamen

To explore the role of alpha-synuclein (αSyn) oligomers and neurofilament light chain (NFL) in cerebrospinal fluid (CSF) as markers of early multiple system atrophy (MSA) and to contrast findings with Lewy body synucleinopathies.. In a discovery cohort of well-characterized early MSA patients (n = 24) and matched healthy controls (CON, n = 14), we utilized enzyme-linked immunosorbent assay to measure NFL and protein misfolding cyclic amplification (PMCA) to detect αSyn oligomers in CSF. We confirmed findings in a separate prospectively enrolled cohort of patients with early MSA (n = 38), Parkinson disease (PD, n = 16), and dementia with Lewy bodies (DLB, n = 13), and CON subjects (n = 15).. In the discovery cohort, NFL was markedly elevated in MSA patients, with perfect separation from CON. αSyn-PMCA was nonreactive in all CON, whereas all MSA samples were positive. In the confirmatory cohort, NFL again perfectly separated MSA from CON, and was significantly lower in PD and DLB compared to MSA. PMCA was again nonreactive in all CON, and positive in all but 2 MSA cases. All PD and all but 2 DLB samples were also positive for αSyn aggregates but with markedly different reaction kinetics from MSA; aggregation occurred later, but maximum fluorescence was higher, allowing for perfect separation of reactive samples between MSA and Lewy body synucleinopathies.. NFL and αSyn oligomers in CSF faithfully differentiate early MSA not only from CON but also from Lewy body synucleinopathies. The findings support the role of these markers as diagnostic biomarkers, and have important implications for understanding pathophysiologic mechanisms underlying the synucleinopathies. ANN NEUROL 2020;88:503-512.

Topics: Aged; alpha-Synuclein; Biomarkers; Diagnosis, Differential; Female; Humans; Lewy Body Disease; Male; Middle Aged; Multiple System Atrophy; Neurofilament Proteins; Parkinson Disease

The differential diagnosis between multiple system atrophy parkinsonism type (MSA-P) and Parkinson's disease with orthostatic hypotension (PD+OH) is difficult because the 2 diseases have a similar clinical picture. The aim of this study is to distinguish MSA-P from PD+OH by immunostaining for abnormal phosphorylated α-synuclein at serine 129 (p-syn) in cutaneous nerves.. We recruited 50 patients with parkinsonism and chronic orthostatic hypotension: 25 patients fulfilled the diagnostic criteria for MSA-P and 25 patients for PD+OH. The patients underwent a skin biopsy from the cervical area, thigh, and leg to analyze somatic and autonomic skin innervation and p-syn in skin nerves.. Intraneural p-syn positivity was found in 72% of patients with MSA-P, mainly in distal skin sites. More important, p-syn deposits in MSA-P differed from PD+OH because they were mainly found in somatic fibers of subepidermal plexi, whereas scant autonomic fiber involvement was found in only 3 patients. All patients with PD+OH displayed widely distributed p-syn deposits in the autonomic skin fibers of proximal and distal skin sites, whereas somatic fibers were affected only slightly in 4 patients with PD+OH. Skin innervation mirrored p-syn deposits because somatic innervation was mainly reduced in MSA-P. Sympathetic innervation was damaged in PD+OH but fairly preserved in MSA-P.. The p-syn in cutaneous nerves allows the differentiation of MSA-P from PD+OH; MSA-P mainly shows somatic fiber involvement with relatively preserved autonomic innervation; and by contrast, PD+OH displays prevalent abnormal p-syn deposits and denervation in autonomic postganglionic nerves. © 2020 International Parkinson and Movement Disorder Society.

Topics: alpha-Synuclein; Biopsy; Humans; Hypotension, Orthostatic; Multiple System Atrophy; Parkinson Disease

It is unclear whether tau-positive granular glial pathology is a characteristic feature of MSA. We aimed to analyse the prevalence and significance of tau-positive granular glial pathology in MSA.. Fourteen MSA cases were clinicopathologically investigated, focusing on tau-positive granular glial pathology in the frontal and temporal white matter and putamen.. In five MSA cases, the temporal white matter showed AT8-positive granular glial pathology; this pathology was detected in the frontal white matter in three cases. AT8-positive granular glia in the white matter were associated with long disease duration with long-term tube feeding and/or long-term tracheotomy. Alpha-synuclein-positive glial cytoplasmic inclusion intensity was not associated with AT8-positive granular glial pathology. The tau isoform of AT8-positive granular glia in the cerebral white matter exhibited three-repeat, not four-repeat, tau. Ten MSA patients showed tau-positive granular glial pathology in the putamen; the tau isoform was predominantly three-repeat tau and four-repeat tau in cases with disease duration ≥13 years and < 13 years, respectively.. Tau-positive granular glia in the putamen is a characteristic pathological feature of MSA. Tau-positive granular glia appear in the cerebral white matter in MSA patients and are associated with long disease duration with long-term tube feeding and/or long-term tracheotomy.

Topics: alpha-Synuclein; Humans; Multiple System Atrophy; Neuroglia; Survivors; tau Proteins; White Matter

Multiple system atrophy (MSA) is pathologically characterized by the presence of fibrillar α-synuclein-immunoreactive inclusions in oligodendrocytes. Although the myelinating process of oligodendrocytes can be observed in adult human brains, little is known regarding the presence of α-synuclein pathology in immature oligodendrocytes and how their maturation and myelination are affected in MSA brains. Recently, breast carcinoma amplified sequence 1 (BCAS1) has been found to be specifically expressed in immature oligodendrocytes undergoing maturation and myelination. Here, we analyzed the altered dynamics of oligodendroglial maturation in both MSA brains and primary oligodendroglial cell cultures which were incubated with α-synuclein pre-formed fibrils. The numbers of BCAS1-expressing oligodendrocytes that displayed a matured morphology negatively correlated with the density of pathological inclusions in MSA brains but not with that in Parkinson's disease and diffuse Lewy body disease. In addition, a portion of the BCAS1-expressing oligodendrocyte population showed cytoplasmic inclusions, which were labeled with antibodies against phosphorylated α-synuclein and cleaved caspase-9. Further in vitro examination indicated that the α-synuclein pre-formed fibrils induced cytoplasmic inclusions in the majority of BCAS1-expressing oligodendrocytes. In contrast, the majority of BCAS1-non-expressing mature oligodendrocytes did not develop inclusions on day 4 after maturation induction. Furthermore, exposure of α-synuclein pre-formed fibrils in the BCAS1-positive phase caused a reduction in oligodendroglial cell viability. Our results indicated that oligodendroglial maturation and myelination are impaired in the BCAS1-positive phase of MSA brains, which may lead to the insufficient replacement of defective oligodendrocytes. In vitro, the high susceptibility of BCAS1-expressing primary oligodendrocytes to the extracellular α-synuclein pre-formed fibrils suggests the involvement of insufficient oligodendroglial maturation in MSA disease progression and support the hypothesis that the BCAS1-positive oligodendrocyte lineage cells are prone to take up aggregated α-synuclein in vivo.

Topics: alpha-Synuclein; Animals; Cell Differentiation; Humans; Multiple System Atrophy; Neoplasm Proteins; Nerve Tissue Proteins; Oligodendrocyte Precursor Cells; Oligodendroglia; Rats; Rats, Sprague-Dawley

Topics: alpha-Synuclein; Cerebellum; Humans; Multiple System Atrophy; Parkinson Disease; Probability

Misfolded oligomeric α-synuclein plays a pivotal role in the pathogenesis of α-synucleinopathies including Parkinson's disease and multiple system atrophy, and its detection parallels activation of microglia and a loss of neurons in the substantia nigra pars compacta. Here we aimed to analyze the therapeutic efficacy of PD03, a new AFFITOPE® immunotherapy approach, either alone or in combination with Anle138b, in a PLP-α-syn mouse model.. The PLP-α-syn mice were treated with PD03 immunotherapy, Anle138b, or a combination of two. Five months after study initiation, the mice underwent behavioral testing and were sacrificed for neuropathological analysis. The treatment groups were compared to the vehicle group with regard to motor performance, nigral neuronal loss, microglial activation and α-synuclein pathology.. The PLP-α-syn mice receiving the PD03 or Anle138b single therapy showed improvement of gait deficits and preservation of nigral dopaminergic neurons associated with the reduced α-synuclein oligomer levels and decreased microglial activation. The combined therapy with Anle138b and PD03 resulted in lower IgG binding in the brain as compared to the single immunotherapy with PD03.. PD03 and Anle138b can selectively target oligomeric α-synuclein, resulting in attenuation of neurodegeneration in the PLP-α-syn mice. Both approaches are potential therapies that should be developed further for disease modification in α-synucleinopathies.

Topics: alpha-Synuclein; Animals; Benzodioxoles; Drug Delivery Systems; Female; Immunologic Factors; Male; Mice; Mice, Transgenic; Multiple System Atrophy; Neurodegenerative Diseases; Pyrazoles

Cardiac [123I]metaiodobenzylguanidine scintigraphy (123I-MIBG) is considered a useful test in differentiating multiple system atrophy (MSA) and Lewy body disorders (LBD), including idiopathic Parkinson's disease (IPD), dementia with Lewy bodies (DLB) and pure autonomic failure (PAF). The detection of skin nerve phosphorylated α-synuclein (p-α-syn) deposits could be an alternative marker in vivo. We sought to compare 123I-MIBG scintigraphy and skin biopsy findings in α-synucleinopathies.. We studied 54 patients (7 DLB, 21 IPD, 13 PAF, 13 MSA) who underwent 123I-MIBG scintigraphy and skin biopsy to evaluate cardiac innervation and skin p-α-syn deposition, respectively.. Cardiac denervation was observed in 90.5% IPD, 100% DLB and PAF and in none of the MSA patients (P < 0.0001) whereas p-α-syn deposits were detected in all DLB and PAF, in 95.2% of IPD and 69.2% of MSA patients (P = 0.02). However, the analysis of skin structures disclosed a different distribution of the deposits in somatic subepidermal plexus and autonomic fibers among groups, showing that p-α-syn deposits rarely affected the autonomic fibers in MSA as opposed to LBD. Studying the p-α-syn deposition in autonomic nerves, concordance among I123-MIBG scintigraphy and skin biopsy results was observed in 100% of DLB and PAF, 95.2% IPD and 92.3% MSA patients. I123-MIBG scintigraphy and autonomic p-α-syn deposits analysis both showed a sensitivity of 97.5% and a specificity of 100% and 92.3%, respectively, in distinguishing LBD and MSA.. Skin biopsy and 123-MIBG scintigraphy can be considered alternative tests for the differential diagnosis of IPD, PAF and DLB versus MSA.

Topics: 3-Iodobenzylguanidine; Aged; alpha-Synuclein; Female; Heart; Humans; Lewy Body Disease; Male; Middle Aged; Multiple System Atrophy; Myocardium; Parkinson Disease; Peripheral Nerves; Phosphorylation; Pure Autonomic Failure; Radionuclide Imaging; Radiopharmaceuticals; Skin

The synucleinopathy underlying multiple system atrophy (MSA) is characterized by the presence of abundant amyloid inclusions containing fibrillar α-synuclein (α-syn) aggregates in the brains of the patients and is associated with an extensive neurodegeneration. In contrast to Parkinson's disease (PD) where the pathological α-syn aggregates are almost exclusively neuronal, the α-syn inclusions in MSA are principally observed in oligodendrocytes (OLs) where they form glial cytoplasmic inclusions (GCIs). This is intriguing because differentiated OLs express low levels of α-syn, yet pathogenic amyloid α-syn seeds require significant amounts of α-syn monomers to feed their fibrillar growth and to eventually cause the buildup of cytopathological inclusions. One of the transgenic mouse models of this disease is based on the targeted overexpression of human α-syn in OLs using the PLP promoter. In these mice, the histopathological images showing a rapid emergence of S129-phosphorylated α-syn inside OLs are considered as equivalent to GCIs. Instead, we report here that they correspond to the accumulation of phosphorylated α-syn monomers/oligomers and not to the appearance of the distinctive fibrillar α-syn aggregates that are present in the brains of MSA or PD patients. In spite of a propensity to co-sediment with myelin sheath contaminants, the phosphorylated forms found in the brains of the transgenic animals are soluble (>80%). In clear contrast, the phosphorylated species present in the brains of MSA and PD patients are insoluble fibrils (>95%). Using primary cultures of OLs from PLP-αSyn mice we observed a variable association of S129-phosphorylated α-syn with the cytoplasmic compartment, the nucleus and with membrane domains suggesting that OLs functionally accommodate the phospho-α-syn deriving from experimental overexpression. Yet and while not taking place spontaneously, fibrillization can be seeded in these primary cultures by challenging the OLs with α-syn preformed fibrils (PFFs). This indicates that a targeted overexpression of α-syn does not model GCIs in mice but that it can provide a basis for seeding aggregation using PFFs. This approach could help establishing a link between α-syn aggregation and the development of a clinical phenotype in these transgenic animals.

Topics: alpha-Synuclein; Amyloid; Animals; Brain; Cells, Cultured; Humans; Mice, Inbred C57BL; Mice, Transgenic; Models, Animal; Multiple System Atrophy; Myelin Basic Protein; Myelin Proteolipid Protein; Neurons; Oligodendroglia; Parkinson Disease; Phosphorylation; Phosphoserine; Promoter Regions, Genetic; Protein Aggregates; Protein Multimerization

Alpha-synuclein (α-Syn) aggregation is the primary characteristic of synucleinopathies including Parkinson's disease (PD), dementia with Lewy bodies (DLB) and multiple system atrophy (MSA). Immunotherapy targeting α-Syn has shown promising results in animal models of the disease. This study investigates the target specificity of three different active vaccines for pathological α-Syn aggregates found in human brain tissue from synucleinopathies.. Guinea pigs were immunised with 3 vaccines developed by United Neuroscience, and IgG fractions purified from the resulting immune sera (IGG-1, IGG-2 or IGG-3) were used to perform immunohistochemical staining of human cases of PD, DLB and MSA. The resulting immunoreactivity was compared to a commercially available α-Syn antibody from Novacastra (NOV) commonly used for diagnostic purposes. Images were captured from the substantia nigra (SN), temporal lobe, internal capsule, insular cortex and putamen and quantified for the percentage area with α-Syn immunoreactivity. Lewy bodies (LB) and Lewy neurites (LN) were further analysed in PD and DLB cases.. Vaccine-generated antibodies detected more α-Syn pathology compared to NOV. The levels of α-Syn immunoreactivity varied between brain region and disease type with IGG-3 recognising the highest levels of α-Syn in most cases and in all brain regions that are affected early in disease progression. IGG-3 had a high recognition for glial inclusions found in MSA which are known to have a more compact conformation. Slot blot analysis confirmed the specificity of IGG-3 for native oligomers and fibrillar α-Syn. Higher levels of α-Syn were recognised by IGG-2 in cortical regions, and by IGG-3 in SN of PD and DLB cases. This was due to increased immunolabelling of LNs in these brain regions suggesting that IGG-2 and IGG-3 recognised additional α-Syn pathology compared to IGG-1 and NOV. Whether the unique binding properties of the antibodies produced in guinea pigs will translate in the clinic remains to be addressed, which is the main limitation of this study.. These vaccines induce antibodies that bind α-Syn oligomers and aggregates in the human brain and specifically support the choice of the vaccine generating IGG-3 (i.e. UB-312) as a candidate for clinical trials for synucleinopathies.

Topics: alpha-Synuclein; Animals; Brain; Guinea Pigs; Immunotherapy; Lewy Body Disease; Multiple System Atrophy; Parkinson Disease; Synucleinopathies

Topics: alpha-Synuclein; Atrophy; Humans; Multiple System Atrophy; Myoclonus; Spinal Cord

To test the hypothesis that myoclonus in patients with multiple system atrophy with predominant cerebellar ataxia (MSA-C) is associated with a heavier burden of α-synuclein deposition in the motor regions of the spinal cord, we compared the degree of α-synuclein deposition in spinal cords of 3 patients with MSA-C with myoclonus and 3 without myoclonus.. All human tissue was obtained by the Massachusetts General Hospital Department of Pathology with support from and according to neuropathology guidelines of the Massachusetts Alzheimer's Disease Research Center. Tissue was stained with Luxol fast blue and hematoxylin & eosin for morphologic evaluation, and with a mouse monoclonal antibody to α-synuclein and Vectastain DAB kit. Images of the spinal cord sections were digitized using a 10× objective lens. Grayscale versions of these images were transferred to ImageJ software for quantitative analysis of 8 different regions of interest (ROIs) in the spinal cord: dorsal column, anterior white column, left and right dorsal horns, left and right anterior horns, and left and right lateral corticospinal tracts. A mixed-effect, multiple linear regression model was constructed to determine if patients with and without myoclonus had significantly different distributions of α-synuclein deposition across the various ROIs.. Patients with myoclonus had more α-synuclein in the anterior horns (. In MSA-C, myoclonus appears to be associated with a higher burden of α-synuclein deposition within spinal cord motor regions. Future studies with more patients will be needed to confirm these findings.

Topics: alpha-Synuclein; Brain; Cerebellar Ataxia; Female; Humans; Male; Middle Aged; Multiple System Atrophy; Myoclonus; Parkinson Disease; Spinal Cord

The synucleinopathies Parkinson's disease (PD) and Multiple system atrophy (MSA) - characterized by α-synuclein intracytoplasmic inclusions into, respectively, neurons and oligodendrocytes - are associated with impairment of the autophagy-lysosomal pathways (ALP). Increased expression of the master regulator of ALP, transcription factor EB (TFEB), is hypothesized to promote the clearance of WT α-synuclein and survival of dopaminergic neurons. Here, we explore the efficacy of targeted TFEB overexpression either in neurons or oligodendrocytes to reduce the pathological burden of α-synuclein in a PD rat model and a MSA mouse model. While TFEB neuronal expression was sufficient to prevent neurodegeneration in the PD model, we show that only TFEB oligodendroglial overexpression leads to neuroprotective effects in the MSA model. These beneficial effects were associated with a decreased accumulation of α-synuclein into oligodendrocytes through recovery of the ALP machinery. Our study demonstrates that the cell type where α-synuclein aggregates dictates the target of TFEB overexpression in order to be protective, paving the way for adapted therapies.

Topics: Aged; alpha-Synuclein; Animals; Autophagy; Basic Helix-Loop-Helix Leucine Zipper Transcription Factors; Brain; Cell Line, Tumor; Disease Models, Animal; HEK293 Cells; Humans; Male; Mice; Mice, Inbred C57BL; Multiple System Atrophy; Oligodendroglia; Parkinson Disease; Rats; Rats, Sprague-Dawley

This study aimed to determine whether enteric neurons are involved in multiple system atrophy (MSA). Four-μm-thick slices of small intestine were prepared from 10%-formalin-fixed and paraffin-embedded materials obtained from autopsied cases. Enteric neurons were stained using an anti-peripherin antibody. Immunostaining of phosphorylated α-synuclein was also performed. Areas of the cytoplasm and nucleus that showed nucleoli were measured using computer software. Both areas of myenteric neurons were significantly smaller in MSA cases (n = 3) than in control subjects (n = 3) (P < 0.0001); however, no deposits of phosphorylated α-synuclein were observed. These findings suggest that myenteric neurons in MSA are affected independent of α-synuclein accumulation.

Topics: Aged; alpha-Synuclein; Cell Size; Female; Humans; Intestine, Small; Male; Multiple System Atrophy; Myenteric Plexus; Neurons; Peripherins; Phosphorylation; Protein Processing, Post-Translational; Submucous Plexus

Synucleinopathies [Parkinson's disease (PD), dementia with Lewy bodies (DLB) and multiple system atrophy (MSA)] share filamentous α-synuclein assemblies in nerve cells and glial cells. We compared the abilities of brain extracts from MSA and PD patients to induce neuronal α-synuclein assembly and neurodegeneration following intracerebral injection in heterozygous mice transgenic for human mutant A53T α-synuclein. MSA extracts were more potent than PD extracts in inducing α-synuclein assembly and in causing neurodegeneration. MSA assemblies were Campbell-Switzer- and Gallyas-silver-positive, whereas PD assemblies were only Campbell-Switzer-positive, in confirmation of previous findings. However, induced α-synuclein inclusions were invariably Campbell-Switzer-positive and Gallyas-negative, irrespective of whether MSA or PD brain extracts were injected. The α-synuclein inclusions of non-injected homozygous mice transgenic for A53T α-synuclein were also Campbell-Switzer-positive and Gallyas-negative. These findings demonstrate that transgene expression and its intracellular environment dominated over the silver staining properties of the conformers of assembled α-synuclein.

Topics: alpha-Synuclein; Animals; Brain; Brain Chemistry; Humans; Mice; Mice, Transgenic; Multiple System Atrophy; Neurons; Parkinson Disease; Silver Staining; Stereotaxic Techniques

The group of neurodegenerative diseases, Parkinson's disease (PD), dementia with Lewy bodies (DLB), and multiple system atrophy (MSA) all exhibit inclusions containing amyloid-type α-synuclein (α-syn) aggregates within degenerating brain cells. α-syn also exists as soluble oligomeric species that are hypothesized to represent intermediates between its native and aggregated states. These oligomers are present in brain extracts from patients suffering from synucleinopathies and hold great potential as biomarkers. Although easily prepared in vitro, oligomers are metastable and dissociate over time, thereby complicating α-syn oligomer research. Using the small amine-reactive cross-linker, formaldehyde (FA), we successfully stabilized α-syn oligomers without affecting their size, overall structure or antigenicity towards aggregate-conformation specific α-syn antibodies FILA and MJFR-14-6-4-2. Further, cross-linked α-syn oligomers show resistance towards denaturant like urea and SDS treatment and remain fully functional as internal standard in an aggregation-specific enzyme-linked immunosorbent assay (ELISA) despite prior incubation with urea. We propose that FA cross-linked α-syn oligomers could serve as important calibrators to facilitate comparative and standardized α-syn biomarker studies going forward.

Topics: alpha-Synuclein; Amyloid; Formaldehyde; Humans; Lewy Body Disease; Multiple System Atrophy; Parkinson Disease; Protein Multimerization; Protein Stability

Aggregation of alpha-synuclein (α-syn) is considered to be the major pathological hallmark and driving force of Multiple System Atrophy (MSA) and Parkinson's disease (PD). Immune dysfunctions have been associated with both MSA and PD and recently we reported that the levels of natural occurring autoantibodies (NAbs) with high-affinity/avidity toward α-synuclein are reduced in MSA and PD patients. Here, we aimed to evaluate the plasma immunoglobulin (Ig) composition binding α-syn and other amyloidogenic neuropathological proteins, and to correlate them with disease severity and duration in MSA and PD patients. All participants were recruited from a single neurological unit and the plasma samples were stored for later research at the Bispebjerg Movement Disorder Biobank. All patients were diagnosed according to current consensus criteria. Using multiple variable linear regression analyses, we observed higher levels of anti-α-syn IgG1 and IgG3 NAbs in MSA vs. PD, higher levels of anti-α-syn IgG2 NAbs in PD compared to controls, whereas anti-α-syn IgG4 NAbs were reduced in PD compared to MSA and controls. Anti-α-syn IgM levels were decreased in both MSA and PD. Further our data supported that MSA patients' immune system was affected with reduced IgG1 and IgM global levels compared to PD and controls, with further reduced global IgG2 levels compared to PD. These results suggest distinct autoimmune patterns in MSA and PD. These findings suggest a specific autoimmune physiological mechanism involving responses toward α-syn, differing in neurodegenerative disease with overlapping α-syn pathology.

Topics: Adult; Aged; Aged, 80 and over; alpha-Synuclein; Autoantibodies; Female; Humans; Immunoglobulin G; Immunoglobulin M; Male; Middle Aged; Multiple System Atrophy; Parkinson Disease; Young Adult

Synucleinopathies [Parkinson's disease with or without dementia, dementia with Lewy bodies and multiple system atrophy] are neurodegenerative diseases that are defined by the presence of filamentous α-synuclein inclusions. We investigated the ability of luminescent conjugated oligothiophenes to stain the inclusions of Parkinson's disease and multiple system atrophy. They stained the Lewy pathology of Parkinson's disease and the glial cytoplasmic inclusions of multiple system atrophy. Spectral analysis of HS-68-stained inclusions showed a red shift in multiple system atrophy, but the difference with Parkinson's disease was not significant. However, when inclusions were double-labelled for HS-68 and an antibody specific for α-synuclein phosphorylated at S129, they could be distinguished based on colour shifts with blue designated for Parkinson's disease and red for multiple system atrophy. The inclusions of Parkinson's disease and multiple system atrophy could also be distinguished using fluorescence lifetime imaging. These findings are consistent with the presence of distinct conformers of assembled α-synuclein in Parkinson's disease and multiple system atrophy.

Topics: Aged; Aged, 80 and over; alpha-Synuclein; Diagnosis, Differential; Female; Fluorescent Dyes; Humans; Luminescent Measurements; Male; Middle Aged; Multiple System Atrophy; Optical Imaging; Parkinson Disease; Thiophenes

Parkinson's disease (PD) and Multiple System Atrophy (MSA) are clinically distinctive diseases that feature a common neuropathological hallmark of aggregated α-synuclein. Little is known about how differences in α-synuclein aggregate structure affect disease phenotype. Here, we amplified α-synuclein aggregates from PD and MSA brain extracts and analyzed the conformational properties using fluorescent probes, NMR spectroscopy and electron paramagnetic resonance. We also generated and analyzed several in vitro α-synuclein polymorphs. We found that brain-derived α-synuclein fibrils were structurally different to all of the in vitro polymorphs analyzed. Importantly, there was a greater structural heterogeneity among α-synuclein fibrils from the PD brain compared to those from the MSA brain, possibly reflecting on the greater variability of disease phenotypes evident in PD. Our findings have significant ramifications for the use of non-brain-derived α-synuclein fibrils in PD and MSA studies, and raise important questions regarding the one disease-one strain hypothesis in the study of α-synucleinopathies.

Topics: Aged; Aged, 80 and over; alpha-Synuclein; Brain; Female; Humans; Male; Models, Molecular; Multiple System Atrophy; Parkinson Disease; Protein Aggregation, Pathological; Protein Conformation; Synucleinopathies; Tissue Extracts

Synucleinopathies are mostly sporadic neurodegenerative disorders of partly unexplained aetiology, and include Parkinson's disease (PD) and multiple system atrophy (MSA). We have further investigated our recent finding of somatic SNCA (α-synuclein) copy number variants (CNVs, specifically gains) in synucleinopathies, using Fluorescent in-situ Hybridisation for SNCA, and single-cell whole genome sequencing for the first time in a synucleinopathy. In the cingulate cortex, mosaicism levels for SNCA gains were higher in MSA and PD than controls in neurons (> 2% in both diseases), and for MSA also in non-neurons. In MSA substantia nigra (SN), we noted SNCA gains in > 3% of dopaminergic (DA) neurons (identified by neuromelanin) and neuromelanin-negative cells, including olig2-positive oligodendroglia. Cells with CNVs were more likely to have α-synuclein inclusions, in a pattern corresponding to cell categories mostly relevant to the disease: DA neurons in Lewy-body cases, and other cells in the striatonigral degeneration-dominant MSA variant (MSA-SND). Higher mosaicism levels in SN neuromelanin-negative cells may correlate with younger onset in typical MSA-SND, and in cingulate neurons with younger death in PD. Larger sample sizes will, however, be required to confirm these putative findings. We obtained genome-wide somatic CNV profiles from 169 cells from the substantia nigra of two MSA cases, and pons and putamen of one. These showed somatic CNVs in ~ 30% of cells, with clonality and origins in segmental duplications for some. CNVs had distinct profiles based on cell type, with neurons having a mix of gains and losses, and other cells having almost exclusively gains, although control data sets will be required to determine possible disease relevance. We propose that somatic SNCA CNVs may contribute to the aetiology and pathogenesis of synucleinopathies, and that genome-wide somatic CNVs in MSA brain merit further study.

Topics: alpha-Synuclein; Brain; DNA Copy Number Variations; Gyrus Cinguli; Humans; Male; Multiple System Atrophy; Neurons; Parkinson Disease; Single-Cell Analysis

α-Synuclein is the major component of Lewy bodies and a candidate biomarker for neurodegenerative diseases in which Lewy bodies are common, including Parkinson's disease and dementia with Lewy bodies. A large body of literature suggests that these disorders are characterized by reduced concentrations of α-synuclein in cerebrospinal fluid (CSF), with overlapping concentrations compared to healthy controls and variability across studies. Several reasons can account for this variability, including technical ones, such as inter-assay and inter-laboratory variation (reproducibility). We compared four immunochemical methods for the quantification of α-synuclein concentration in 50 unique CSF samples. All methods were designed to capture most of the existing α-synuclein forms in CSF ('total' α-synuclein). Each of the four methods showed high analytical precision, excellent correlation between laboratories (R

Topics: alpha-Synuclein; Biomarkers; Female; Humans; Immunoassay; Lewy Body Disease; Male; Multiple System Atrophy; Parkinson Disease; Reference Values; Reproducibility of Results

Topics: Aged; alpha-Synuclein; Brain; Humans; Inclusion Bodies; Male; Multiple System Atrophy; Synucleinopathies

Multiple system atrophy(MSA) is a neurodegenerative disease characterized by intracellular α-synuclein deposits. There is an unmet need for blood-based biomarkers to diagnose MSA. Our previous studies have reported elevated α-synuclein levels in erythrocytes of MSA patients. However, α-synuclein protein in the membrane and cytoplasm of erythrocytes in MSA have not been investigated.. The membrane and cytoplasm were extracted from erythrocytes in 77 patients with MSA and 133 healthy controls. Levels of total and oligomeric α-synuclein were detected using Electrochemiluminescence assays. The correlations between α-synuclein levels and clinical characteristics were explored in MSA group. The diagnostic value of erythrocyte α-synuclein for MSA was determined by Receiver operator characteristic curve.. α-synuclein levels in the erythrocyte membrane were significantly elevated in MSA patients compared with the healthy controls (total α-synuclein, p = 0.003; oligomeric α-synuclein/total α-synuclein, p = 0.033; oligomeric α-synuclein/protein, p < 0.001). The combination of total and oligomeric α-synuclein levels in erythrocyte membrane could efficiently distinguish MSA from healthy controls (sensitivity of 79.2%; specificity of 69.2%; area under the curve: 0.771). In contrast, no significant difference was found in erythrocyte cytoplasm α-synuclein levels. In the subgroup of 48 patients with probable MSA, there was a weakly negative correlation between oligomeric α-synuclein/protein in erythrocyte membrane and disease duration (r = -0.336; p = 0.009).. Our pilot study suggests that the membrane fraction of α-synuclein levels in erythrocyte were elevated in patients with MSA, and these levels may be decreased with the development of disease.

Topics: Aged; alpha-Synuclein; Biomarkers; Electrochemical Techniques; Erythrocyte Membrane; Female; Humans; Luminescence; Male; Middle Aged; Multiple System Atrophy; Pilot Projects

We previously reported up-regulation of tigarb (the zebrafish orthologue of human TIGAR, TP53 - Induced Glycolysis and Apoptosis Regulator) in a zebrafish pink1. TIGAR Immunohistochemistry, using a range of antibodies, was undertaken for detailed assessment of TIGAR in formalin-fixed, paraffin-embedded tissue from post mortem brains of PD patients and other neurodegenerative disorders (n = 10 controls, 10 PD cases, 10 dementia with Lewy bodies, 5 motor neurone disease (MND), 3 multiple system atrophy (MSA)) and complemented by immunohistochemistry for p53, hexokinase I (HK-I) and hexokinase II (HK-II; n = 4 control, 4 PD, and 4 dementia with Lewy bodies).. TIGAR was detected in Lewy bodies and Lewy neurites in the substantia nigra of sporadic PD and Dementia with Lewy bodies (DLB) patients. Staining of adjacent sections and double staining confirmed the presence of TIGAR alongside alpha-synuclein in these LB and neurites. In contrast, TIGAR-positive aggregates were not seen in cortical Lewy bodies. TIGAR protein was also absent in both TDP-43-positive inclusions in MND and glial cytoplasmic inclusions in MSA. Subsequent investigation of the TIGAR-upstream regulator p53 and the downstream targets HK-I and HK-II in PD brains suggested a possible mild increase in HK-I.. TIGAR protein, is present in SN Lewy bodies of both sporadic PD and DLB. The absence of TIGAR protein in the pathological inclusions of MND or MSA suggests disease specificity and further raises the possibility that TIGAR may be involved in PD pathogenesis.

Topics: Aged; Aged, 80 and over; alpha-Synuclein; Apoptosis Regulatory Proteins; Brain; Dementia; Female; Humans; Immunohistochemistry; Inclusion Bodies; Lewy Bodies; Lewy Body Disease; Male; Middle Aged; Motor Neuron Disease; Multiple System Atrophy; Neurites; Neurons; Parkinson Disease; Phosphoric Monoester Hydrolases; Substantia Nigra

Neuroinflammation and oligodendroglial cytoplasmic α-synuclein (α-syn) inclusions (GCIs) are important neuropathological characteristics of multiple system atrophy (MSA). GCIs are known to interfere with oligodendroglial maturation and consequently result in myelin loss. The neuroinflammatory phenotype in the context of MSA, however, remains poorly understood. Here, we demonstrate MSA-associated neuroinflammation being restricted to myeloid cells and tightly linked to oligodendroglial α-syncleinopathy. In human putaminal post-mortem tissue of MSA patients, neuroinflammation was observed in white matter regions only. This locally restricted neuroinflammation coincided with elevated numbers of α-syn inclusions, while gray matter with less α-synucleinopathy remained unaffected. In order to analyze the temporal pattern of neuroinflammation, a transgenic mouse model overexpressing human α-syn under the control of an oligodendrocyte-specific myelin basic protein (MBP) promoter (MBP29-hα-syn mice) was assessed in a pre-symptomatic and symptomatic disease stage. Strikingly, we detected an increased neuroinflammation in regions with a high α-syn load, the corpus callosum and the striatum, of MBP29-hα-syn mice, already at a pre-symptomatic stage. Furthermore, this inflammatory response was restricted to myeloid cells being highly proliferative and showing an activated, phagocytic phenotype. In contrast, severe astrogliosis was observed only in gray matter regions of MSA patients as well as MBP29-hα-syn mice. To further characterize the influence of oligodendrocytes on initiation of the myeloid immune response, we performed RNA sequencing analysis of α-syn overexpressing primary oligodendrocytes. A distinct gene expression profile including upregulation of cytokines important for myeloid cell attraction and proliferation was detected in α-syn overexpressing oligodendrocytes. Additionally, microdissected tissue of MBP29-hα-syn mice exhibited a similar cellular gene expression profile in white matter regions even pre-symptomatically. Collectively, these results imply an early crosstalk between neuroinflammation and oligodendrocytes containing α-syn inclusions leading to an immune response locally restricted to white matter regions in MSA.

Topics: Aged; alpha-Synuclein; Animals; Brain; Corpus Striatum; Disease Models, Animal; Female; Humans; Inclusion Bodies; Male; Mice; Mice, Transgenic; Middle Aged; Multiple System Atrophy; Myeloid Cells; Neuroimmunomodulation; Neurons; Oligodendroglia; Synucleinopathies; White Matter

MSA is a fatal neurodegenerative disease characterized by autonomic failure and severe motor impairment. Its main pathological hallmark is the accumulation of α-synuclein in oligodendrocytes, leading to glial and neuronal dysfunction and neurodegeneration. These features are recapitulated in the PLP-hαSyn mouse model expressing human α-synuclein in oligodendrocytes. At present, there is no effective disease-modifying therapy. Previous experiments have shown that the aggregation inhibitor, anle138b, reduces neurodegeneration and behavioral deficits in mouse models of other proteinopathies.. To test the therapeutic potential of anle138b in a mouse model of MSA.. Two-month-old PLP-hαSyn mice were fed over a period of 4 months with pellets containing anle138b at two different doses (0.6 and 2 g/kg) and compared to healthy controls and PLP-hαSyn mice fed with placebo pellets. At the end of the treatment, behavioral and histological analyses were performed.. We observed a reversal of motor function to healthy control levels when PLP-hαSyn mice were treated with both doses of anle138b. Histological and molecular analyses showed a significant reduction in α-synuclein oligomers and glial cytoplasmic inclusions in animals fed with anle138b compared to nontreated mice. These animals also present preservation of dopaminergic neurons and reduction in microglial activation in SN correlating with the α-synuclein reduction observed.. Anle138b reduces α-synuclein accumulation in PLP-hαSyn mice, leading to neuroprotection, reduction of microglial activation, and preservation of motor function supporting the use of anle138b in a future clinical trial for MSA. © 2018 The Authors. Movement Disorders published by Wiley Periodicals, Inc. on behalf of International Parkinson and Movement Disorder Society.

Topics: alpha-Synuclein; Animals; Benzodioxoles; Disease Models, Animal; Mice, Transgenic; Movement Disorders; Multiple System Atrophy; Nerve Degeneration; Neuroglia; Neurons; Oligodendroglia; Pyrazoles

Topics: alpha-Synuclein; Biosensing Techniques; Brain; HEK293 Cells; Humans; Multiple System Atrophy; Parkinson Disease

Previously, we reported that intracranial inoculation of brain homogenate from multiple system atrophy (MSA) patient samples produces neurological disease in the transgenic (Tg) mouse model TgM83

Topics: alpha-Synuclein; Animals; Humans; Mice; Mice, Transgenic; Multiple System Atrophy; Prion Diseases; Prions

Topics: alpha-Synuclein; Humans; Multiple System Atrophy; Parkinson Disease; Pure Autonomic Failure; Synucleinopathies

Multiple system atrophy (MSA) is a fatal adult-onset neurodegenerative disease that is characterized by varying degrees of cerebellar dysfunction and Parkinsonism. The neuropathological hallmark of MSA is alpha-synuclein (AS)-positive glial cytoplasmic inclusions (GCIs). Although severe neuronal loss (NL) is also observed in MSA, neuronal inclusions (NIs) are rare compared to GCIs, such that the pathological mechanism of NL in MSA is unclear. GCIs and NIs are late-stage pathology features relative to AS oligomers and may not represent early pathological changes in MSA. To reveal the early pathology of MSA, it is necessary to examine the early aggregation of AS, i.e., AS oligomers. Here, we adopted a proximity ligation assay (PLA) to examine the distribution of AS oligomers in brain tissue samples from patients with MSA and other diseases. Surprisingly, MSA brains showed a widespread distribution and abundant accumulation of oligomeric AS in neurons as well as oligodendrocytes of the neocortex. In several regions, oligomeric AS signal intensity was higher in cases with MSA than in cases with Parkinson's disease. In contrast to previous studies, AS-PLA revealed abundant AS oligomer accumulation in Purkinje cells in MSA brains, identifying oligomeric AS accumulation as a possible cause of Purkinje cell loss. This wide distribution of AS oligomers in MSA brain neurons has not been described previously and indicates a pathological mechanism of NL in MSA.

Topics: Aged; Aged, 80 and over; alpha-Synuclein; Brain; Female; Humans; Immunohistochemistry; Inclusion Bodies; Male; Middle Aged; Multiple System Atrophy; Purkinje Cells

Visualization of phosphorylated α-synuclein at serine 129 (p-syn) in skin nerves is a promising test for the in vivo diagnosis of synucleinopathies. Here the aim was to establish the intra- and inter-laboratory reproducibility of measurement of intraneural p-syn immunoreactivity in two laboratories with major expertise (Würzburg and Bologna).. In total, 43 patients affected by Parkinson's disease (PD 21 patients), dementia with Lewy bodies (DLB 1), rapid eye movement sleep behaviour disorder (RBD 11), multiple system atrophy (MSA-P 4) and small fibre neuropathy (SFN 6) were enrolled. Skin biopsy was performed at the C7 paravertebral spine region and distal skin sites (thigh or leg). The analysis was standardized in both laboratories and carried out blinded on a single skin section double stained with antibodies to p-syn and the pan-axonal marker protein gene product 9.5. Fifty skin sections were randomly selected for the analysis: 25 from C7 and 25 from distal sites. Differently classified sections were re-evaluated to understand the reasons for the discrepancy.. The intra-laboratory analysis showed an excellent reproducibility both in Würzburg (concordance of classification 100% of sections; K = 1; P < 0.001) and Bologna (96% of sections; K = 0.92; P < 0.001). Inter-laboratory analysis showed reproducibility in 45 sections (90%; K = 0.8; P < 0.001) and a different classification in five sections, which was mainly due to fragmented skin samples or weak fluorescent signals.. Analysis of p-syn showed excellent inter- and intra-laboratory reproducibility supporting the reliability of this technique. The few ascertained discordances were important to further improve the standardization of this technique.

Topics: Adult; Aged; Aged, 80 and over; alpha-Synuclein; Biopsy; Female; Humans; Immunohistochemistry; Male; Middle Aged; Multiple System Atrophy; Nervous System Diseases; Parkinson Disease; Peripheral Nerves; Phosphorylation; REM Sleep Behavior Disorder; Reproducibility of Results; Skin

Proteinaceous α-synuclein-containing inclusions are found in affected brain regions in patients with Parkinson's disease (PD), Dementia with Lewy bodies (DLB) and multiple system atrophy (MSA). These appear in neurons as Lewy bodies in both PD and DLB and as glial cytoplasmic inclusions (GCIs) in oligodendrocytes in MSA. The role they play in the pathology of the diseases is unknown, and relatively little is still known about their composition. By purifying the inclusions from the surrounding tissue and comprehensively analysing their protein composition, vital clues to the formation mechanism and role in the disease process may be found. In this study, Lewy bodies were purified from postmortem brain tissue from DLB cases (n = 2) and GCIs were purified from MSA cases (n = 5) using a recently improved purification method, and the purified inclusions were analysed by mass spectrometry. Twenty-one percent of the proteins found consistently in the GCIs and LBs were synaptic-vesicle related. Identified proteins included those associated with exosomes (CD9), clathrin-mediated endocytosis (clathrin, AP-2 complex, dynamin), retrograde transport (dynein, dynactin, spectrin) and synaptic vesicle fusion (synaptosomal-associated protein 25, vesicle-associated membrane protein 2, syntaxin-1). This suggests that the misfolded or excess α-synuclein may be targeted to inclusions via vesicle-mediated transport, which also explains the presence of the neuronal protein α-synuclein within GCIs.

Topics: Aged; Aged, 80 and over; alpha-Synuclein; Female; Humans; Inclusion Bodies; Lewy Bodies; Lewy Body Disease; Male; Middle Aged; Multiple System Atrophy; Oligodendroglia; Protein Aggregation, Pathological; Synaptic Vesicles

Multiple system atrophy (MSA) is an adult-onset neurodegenerative disorder clinically characterized by autonomic failure in addition to various combinations of symptoms of parkinsonism, cerebellar ataxia, and pyramidal dysfunction. Despite extensive research, the mechanisms underlying the progression of MSA remain unknown. Animal models of human diseases that recapitulate their clinical, biochemical and pathological features are indispensable for increasing our understanding of their underlying molecular mechanisms, which allows preclinical studies to be advanced. Because the onset of MSA occurs in middle age, an animal model that first manifests abnormal protein aggregates in adulthood would be most appropriate. We therefore used the Cre-loxP system to express inducible α-synuclein (Syn), a major component of the pathological hallmark of MSA, to generate a mouse model of MSA. Beginning in adulthood, these MSA model mice express excessive levels of Syn in oligodendrocytes, resulting in abnormal Syn accumulation and modifications similar to those observed in human MSA pathology. Additionally, MSA model mice exhibit some clinical features of MSA, including decreased motor activity. These findings suggest that this new mouse model of MSA represents a useful tool for analyzing the pathophysiological alterations that underlie the progression of this disease.

Topics: alpha-Synuclein; Animals; Brain; Disease Models, Animal; Mice; Mice, Transgenic; Motor Activity; Multiple System Atrophy; Oligodendroglia; Phosphorylation

The intercellular transfer of alpha-synuclein (α-syn) has been implicated in the progression of Parkinson's disease (PD) and multiple system atrophy (MSA). The cellular mechanisms underlying this process are now beginning to be elucidated. In this study, we demonstrate that the gap junction protein connexin-32 (Cx32) is centrally involved in the preferential uptake of α-syn oligomeric assemblies (oα-syn) in neurons and oligodendrocytes. In vitro, we demonstrate a clear correlation between Cx32 expression and oα-syn uptake. Pharmacological and genetic strategies targeting Cx32 successfully blocked oα-syn uptake. In cellular and transgenic mice modeling PD and MSA, we observed significant upregulation of Cx32 which correlates with α-syn accumulation. Notably, we could also demonstrate a direct interaction between α-syn and Cx32 in two out of four human PD cases that was absent in all four age-matched controls. These data are suggestive of a link between Cx32 and PD pathophysiology. Collectively, our results provide compelling evidence for Cx32 as a novel target for therapeutic intervention in PD and related α-synucleinopathies.

Topics: alpha-Synuclein; Animals; Brain; Connexins; Gap Junction beta-1 Protein; Mice; Multiple System Atrophy; Neurons; Oligodendroglia; Parkinson Disease

Posttranslational modifications by phosphorylation, ubiquitination, neddylation and other pathways have emerged as major regulators of cellular functions. NEDD8 ultimate buster 1, NUB1, is an adaptor protein, which negatively regulates the levels of the ubiquitin-like protein NEDD8 as well as neddylated proteins through proteasomal degradation. We previously reported that NUB1 is highly involved in the pathogenesis of synucleinopathy including Parkinson's disease (PD), dementia with Lewy bodies (DLB) and multiple system atrophy (MSA). In general, since phosphorylation is strongly related to the alteration of protein propensity, we examined if the fundamental function of NUB1 can be modulated by its phosphorylation. We created a series of phosphomimic mutants of NUB1. Among them, we found that phosphorylation of NUB1 at S46 (P-NUB46) efficiently degrades aggregates using a cell-based assay. Immunohistochemical studies have shown that specific antibodies against P-NUB46 reacted with Lewy bodies in PD and DLB but not with glial cytoplasmic inclusions in MSA. Moreover, P-NUB46 levels were significantly higher in the brains of patients with DLB than in control brains, and P-NUB46 was extracted in an insoluble fraction of DLB. These findings suggest that the phosphorylation of NUB1 is modulated during the pathological process of Lewy body disease.

Topics: Adaptor Proteins, Signal Transducing; Aged; Aged, 80 and over; alpha-Synuclein; Brain; Female; Humans; Inclusion Bodies; Lewy Bodies; Lewy Body Disease; Male; Multiple System Atrophy; NEDD8 Protein; Neuroglia; Parkinson Disease; Phosphorylation

Multiple system atrophy (MSA) is characterized by the presence of distinctive glial cytoplasmic inclusions (GCIs) within oligodendrocytes that contain the neuronal protein alpha-synuclein (aSyn) and the oligodendroglia-specific phosphoprotein TPPP/p25α. However, the role of oligodendroglial aSyn and p25α in the formation of aSyn-rich GCIs remains unclear. To address this conundrum, we have applied human aSyn (haSyn) pre-formed fibrils (PFFs) to rat wild-type (WT)-, haSyn-, or p25α-overexpressing oligodendroglial cells and to primary differentiated oligodendrocytes derived from WT, knockout (KO)-aSyn, and PLP-haSyn-transgenic mice. HaSyn PFFs are readily taken up by oligodendroglial cells and can recruit minute amounts of endogenous aSyn into the formation of insoluble, highly aggregated, pathological assemblies. The overexpression of haSyn or p25α accelerates the recruitment of endogenous protein and the generation of such aberrant species. In haSyn PFF-treated primary oligodendrocytes, the microtubule and myelin networks are disrupted, thus recapitulating a pathological hallmark of MSA, in a manner totally dependent upon the seeding of endogenous aSyn. Furthermore, using oligodendroglial and primary cortical cultures, we demonstrated that pathology-related S129 aSyn phosphorylation depends on aSyn and p25α protein load and may involve different aSyn "strains" present in oligodendroglial and neuronal synucleinopathies. Importantly, this hypothesis was further supported by data obtained from human post-mortem brain material derived from patients with MSA and dementia with Lewy bodies. Finally, delivery of haSyn PFFs into the mouse brain led to the formation of aberrant aSyn forms, including the endogenous protein, within oligodendroglia and evoked myelin decompaction in WT mice, but not in KO-aSyn mice. This line of research highlights the role of endogenous aSyn and p25α in the formation of pathological aSyn assemblies in oligodendrocytes and provides in vivo evidence of the contribution of oligodendroglial aSyn in the establishment of aSyn pathology in MSA.

Topics: alpha-Synuclein; Animals; Brain; Disease Models, Animal; Humans; Mice; Mice, Transgenic; Multiple System Atrophy; Nerve Tissue Proteins; Neurons; Oligodendroglia; Rats; Synucleinopathies

To investigate the prevalence of clinically relevant multiple system atrophy (MSA) and Lewy body disease (LBD) pathologies in a large frontotemporal lobar degeneration (FTLD) cohort to determine if concomitant pathologies underlie the heterogeneity of clinical features.. All prospectively followed FTLD-tau and FTLD-TDP cases held by the Sydney Brain Bank (n = 126) were screened for coexisting MSA and LBD (Braak ≥ stage IV) pathology. Relevant clinical (including family history) and genetic associations were determined.. MSA pathology was not identified in this series. Of the FTLD cohort, 9 cases had coexisting LBD ≥ Braak stage IV and were associated with different FTLD subtypes including Pick disease (n = 2), corticobasal degeneration (n = 2), progressive supranuclear palsy (n = 2), and TDP type A (n = 3). All FTLD-TDP cases with coexisting LBD had mutations in. Coexisting LBD in FTLD comprises a small proportion of cases but has implications for clinical and neuropathologic diagnoses and the identification of biomarkers.

Topics: Aged; Aged, 80 and over; alpha-Synuclein; Brain; C9orf72 Protein; DNA-Binding Proteins; Female; Frontotemporal Lobar Degeneration; Humans; Lewy Body Disease; Male; Middle Aged; Multiple System Atrophy; Parkinsonian Disorders; Prevalence; Progranulins; tau Proteins

Multiple system atrophy (MSA) is a neurodegenerative disease characterised by glial cytoplasmic inclusions (GCIs), containing α-synuclein. Mutated COQ2, encoding an enzyme essential for co-enzyme Q10 (CoQ10) biosynthesis, has been associated with MSA. CoQ10 is an electron carrier in the mitochondrial electron transport chain (ETC) and antioxidant. It has been shown to be deficient in MSA brain tissue, thus implicating mitochondrial dysfunction in MSA. To investigate mitochondrial dysfunction in MSA further we examined ETC activity in MSA and control brain tissue, compared with Parkinson's disease (PD) where mitochondrial dysfunction is known to be important. Using cerebellar and occipital white matter ETC complex I, II/III and IV activities were measured spectrophotometrically, selected individual components of the ETC were assessed by immunoblotting and cellular complex IV activity was analysed by enzyme histochemistry. We show decreased complex II/III activity with increased complex I and IV activity in MSA cerebellar white matter. This corresponds with the deficit in CoQ10 previously described in MSA and reflects the high regional pathological burden of GCIs. This study highlights mitochondrial dysfunction in MSA pathogenesis, suggests an influence on selective regional vulnerability to disease and points to shared disease mechanisms in α-synucleinopathies.

Topics: alpha-Synuclein; Cerebellum; Electron Transport; Humans; Immunoblotting; Inclusion Bodies; Mitochondria; Multiple System Atrophy; Parkinson Disease; Ubiquinone

α-synuclein (αS) is the major component of several types of brain pathological inclusions that define neurodegenerative diseases termed synucleinopathies. Central nervous system (CNS) inoculation studies using either in vitro polymerized αS fibrils or in vivo derived lysates containing αS aggregates to induce the progressive spread of αS inclusion pathology in animal disease models have supported the notion that αS mediated progressive neurodegeneration can occur by a prion-like mechanism. We have previously shown that neonatal brain inoculation with preformed αS fibrils in hemizygous M20

Topics: Aged; Aged, 80 and over; alpha-Synuclein; Animals; Astrocytes; Brain; Disease Models, Animal; Humans; Inclusion Bodies; Mice, Transgenic; Microglia; Middle Aged; Multiple System Atrophy; Neurons; Synucleinopathies

Glial cytoplasmic inclusions (GCIs) containing aggregated and hyperphosphorylated α-synuclein are the signature neuropathological hallmark of multiple system atrophy (MSA). Native α-synuclein can adopt a prion conformation that self-propagates and spreads throughout the brain ultimately resulting in neurodegeneration. A growing body of evidence argues that, in addition to oligodendrocytes, astrocytes contain α-synuclein inclusions in MSA and other α-synucleinopathies at advanced stages of disease. To study the role of astrocytes in MSA, we added MSA brain homogenate to primary cultures of astrocytes from transgenic (Tg) mouse lines expressing human α-synuclein. Astrocytes from four Tg lines, expressing either wild-type or mutant (A53T or A30P) human α-synuclein, propagated and accumulated α-synuclein prions. Furthermore, we found that MSA-infected astrocytes formed two morphologically distinct α-synuclein inclusions: filamentous and granular. Both types of cytoplasmic inclusions shared several features characteristic of α-synuclein inclusions in synucleinopathies: hyperphosphorylation preceded by aggregation, ubiquitination, thioflavin S-positivity, and co-localization with p62. Our findings demonstrate that human α-synuclein forms distinct inclusion morphologies and propagates within cultured Tg astrocytes exposed to MSA prions, indicating that α-synuclein expression determines the tropism of inclusion formation in certain cells. Thus, our work may prove useful in elucidating the role of astrocytes in the pathogenic mechanisms that feature in neurodegeneration caused by MSA prions.

Topics: alpha-Synuclein; Animals; Astrocytes; Cells, Cultured; Dendritic Spines; Humans; Inclusion Bodies; Mice, Transgenic; Multiple System Atrophy; Prions; Recombinant Proteins

Multiple system atrophy (MSA) is a fatal demyelinating disorder lacking any disease-modifying therapies. MSA pathology stems from aggregated α-synuclein (aSyn) accumulation in glial cytosolic inclusions of oligodendroglial cell (OLGs), the myelinating cells of brain. In MSA brains and in MSA animal models with aSyn accumulation in OLGs, aberrant expression of brain-derived neurotrophic factor (BDNF) and glial-cell-line-derived neurotrophic factor (GDNF) occur. Nerve growth factor (NGF) expression can also be altered in neurodegenerative diseases. It is unclear if oxidative stress impacts the viability of aSyn-accumulating OLG cells. Here, we show that OLN-93 cells stably expressing human wild type aSyn or the MSA-associated-aSyn-mutants G51D or A53E, are more vulnerable to oxidative stress. In dose response studies we found that OLN-93 cells treated 48 h with 160 nM FTY720 or our new non-immunosuppressive FTY720-C2 or FTY720-Mitoxy derivatives sustained normal viability. Also, FTY720, FTY720-C2, and FTY720-Mitoxy all stimulated NGF expression at 24 h. However only FTY720-Mitoxy also increased BDNF and GDNF mRNA at 24 h, an effect paralleled by increases in histone 3 acetylation and ERK1/2 phosphorylation. Myelin associated glycoprotein (MAG) levels were also increased in OLN-93 cells after 48 h treatment with FTY720-Mitoxy. FTY720, FTY720-C2, and FTY720-Mitoxy all prevented oxidative-stress-associated-cell-death of OLN-93 cells that lack any aSyn expression. However, only FTY720-Mitoxy protected MSA-like aSyn-expressing-OLN-93-cells against oxidative-cell-death. These data identify potent protective effects for FTY720-Mitoxy with regard to trophic factors as well as MAG expression by OLG cells. Testing of FTY720-Mitoxy in mice is thus a judicious next step for neuropharmacological preclinical development.

Topics: alpha-Synuclein; Animals; Brain-Derived Neurotrophic Factor; Cell Line; Ceramides; Fingolimod Hydrochloride; Glial Cell Line-Derived Neurotrophic Factor; Multiple System Atrophy; Myelin-Associated Glycoprotein; Nerve Growth Factor; Oligodendroglia; Oxidative Stress; Rats; Sphingosine 1 Phosphate Receptor Modulators

Multiple system atrophy (MSA) is a fatal, adult-onset neurodegenerative disorder that has no cure and very limited treatment options. MSA is characterized by deposition of fibrillar α-synuclein (α-syn) in glial cytoplasmic inclusions in oligodendrocytes. Similar to other synucleinopathies, α-syn self-assembly is thought to be a key pathologic event and a prominent target for disease modification in MSA. Molecular tweezers are broad-spectrum nanochaperones that prevent formation of toxic protein assemblies and enhance their clearance. The current lead compound, CLR01, has been shown to inhibit α-syn aggregation but has not yet been tested in the context of MSA. To fill this gap, here, we conducted a proof-of-concept study to assess the efficacy of CLR01 in remodeling MSA-like α-syn pathology in the PLP-α-syn mouse model of MSA. Six-month-old mice received intracerebroventricular CLR01 (0.3 or 1 mg/kg per day) or vehicle for 32 days. Open-field test revealed a significant, dose-dependent amelioration of an anxiety-like phenotype. Subsequently, immunohistochemical and biochemical analyses showed dose-dependent reduction of pathological and seeding-competent forms of α-syn, which correlated with the behavioral phenotype. CLR01 treatment also promoted dopaminergic neuron survival in the substantia nigra. To our knowledge, this is the first demonstration of an agent that reduces formation of putative high-molecular-weight oligomers and seeding-competent α-syn in a mouse model of MSA, supporting the view that these species are key to the neurodegenerative process and its cell-to-cell progression in MSA. Our study suggests that CLR01 is an attractive therapeutic candidate for disease modification in MSA and related synucleinopathies, supporting further preclinical development.

Topics: alpha-Synuclein; Animals; Brain; Bridged-Ring Compounds; Cell Line; Disease Models, Animal; Dopaminergic Neurons; Humans; Male; Mice; Multiple System Atrophy; Neuroprotective Agents; Organophosphates; Protein Aggregation, Pathological

In multiple system atrophy (MSA), progressive neurodegeneration results from the protein α-synuclein misfolding into a self-templating prion conformation that spreads throughout the brain. MSA prions are transmissible to transgenic (Tg) mice expressing mutated human α-synuclein (TgM83

Topics: alpha-Synuclein; Animals; Biological Transport; Brain; Detergents; Disease Models, Animal; Fixatives; Formaldehyde; HEK293 Cells; Humans; Mice, Transgenic; Multiple System Atrophy; Muscle, Skeletal; Mutation; Prions; Protein Aggregates; Protein Stability; Sarcosine; Stainless Steel

α-Synuclein (α-SYN), a presynaptic protein with the tendency to aggregate, is linked to α-synucleinopathies such as Parkinson's disease (PD), dementia with Lewy bodies (DLB), and multiple system atrophy (MSA). α-SYN is the main component of round intracytoplasmic inclusions called Lewy bodies (LBs), which are the hallmark of PD and DLB. In addition, accumulation of amyloid-β and neurofibrillary tangles as in the pathology of Alzheimer's disease has been found in the DLB brain. Glial cytoplasmic inclusions are an MSA-specific type of inclusion found in oligodendrocytes and mainly comprise α-SYN. FK506-binding protein (FKBP) 12 is a member of the immunophilin family with peptidyl-prolyl isomerase activity that promotes protein folding and is believed to act as a chaperone protein. Previous in vitro work indicated that FKBP12 accelerated α-SYN aggregation more than other peptidyl-prolyl isomerases. The enzymatic activity of FKBP12 increases the formation of α-SYN fibrils at subnanomolar concentrations. In this study, we found that FKBP12 colocalized with α-SYN in LBs and neurites in PD and DLB brains. Furthermore, FKBP12-immunopositive neurofibrillary tangles colocalized with phosphorylated tau in DLB and FKBP12-immunopositive glial cytoplasmic inclusions colocalized with α-SYN in MSA. These findings suggest that FKBP12 is linked to the accumulation of α-SYN and phosphorylated tau protein in α-synucleinopathies. FKBP12 may play important roles in the pathogenesis of α-synucleinopathies through its strong aggregation function. Thus, FKBP12 could be an important drug target for α-synucleinopathies.

Topics: Aged; Aged, 80 and over; alpha-Synuclein; Brain; Female; Humans; Lewy Body Disease; Male; Middle Aged; Multiple System Atrophy; Neurites; Neurofibrillary Tangles; Parkinson Disease; Tacrolimus Binding Protein 1A

In the neurodegenerative disease multiple system atrophy (MSA), α-synuclein misfolds into a self-templating conformation to become a prion. To compare the biological activity of α-synuclein prions in MSA and Parkinson's disease (PD), we developed nine α-synuclein-YFP cell lines expressing point mutations responsible for inherited PD. MSA prions robustly infected wild-type, A30P, and A53T α-synuclein-YFP cells, but they were unable to replicate in cells expressing the E46K mutation. Coexpression of the A53T and E46K mutations was unable to rescue MSA prion infection in vitro, establishing that MSA α-synuclein prions are conformationally distinct from the misfolded α-synuclein in PD patients. This observation may have profound implications for developing treatments for neurodegenerative diseases.

Topics: alpha-Synuclein; Animals; Cell Line; HEK293 Cells; Humans; Mice, Transgenic; Multiple System Atrophy; Parkinson Disease; Point Mutation; Prions; Protein Folding

Topics: alpha-Synuclein; Communicable Diseases; Humans; Multiple System Atrophy; Prion Diseases; Proteostasis Deficiencies

Multiple system atrophy (MSA) is a rapidly progressive neurodegenerative disorder characterized by widespread oligodendroglial cytoplasmic inclusions of filamentous α-synuclein, and neuronal loss in autonomic centres, basal ganglia and cerebellar circuits. It has been suggested that primary oligodendroglial α-synucleinopathy may represent a trigger in the pathogenesis of MSA, but the mechanisms underlying selective vulnerability and disease progression are unclear. The post-mortem analysis of MSA brains provides a static final picture of the disease neuropathology, but gives no clear indication on the sequence of pathogenic events in MSA. Therefore, alternative methods are needed to address these issues. We investigated selective vulnerability and disease progression in the transgenic PLP-α-syn mouse model of MSA characterized by targeted oligodendroglial α-synuclein overexpression aiming to provide a neuropathological correlate of motor deterioration. We show progressive motor deficits that emerge at 6 months of age and deteriorate up to 18 months of follow-up. The motor phenotype was associated with dopaminergic cell loss in the substantia nigra pars compacta at 6 months, followed by loss of striatal dopaminergic terminals and DARPP32-positive medium sized projection neurons at 12 months. Olivopontocerebellar motor loops remained spared in the PLP-α-syn model of MSA. These findings replicate progressive striatonigral degeneration underlying Parkinson-variant MSA. The initiation of the degenerative process was linked to an increase of soluble oligomeric α-synuclein species between 2 and 6 months. Early region-specific α-synuclein-associated activation profile of microglia was found in MSA substantia nigra. The role of abnormal neuroinflammatory signalling in disease progression was further supported by increased levels of CD68, CCL3, CCL5 and M-CSF with a peak in aged PLP-α-syn mice. In summary, transgenic PLP-α-syn mice show a distinctive oligodendroglial α-synucleinopathy that is associated with progressive striatonigral degeneration linked to abnormal neuroinflammatory response. The model provides a relevant tool for preclinical therapeutic target discovery for human Parkinson-variant MSA.

Topics: Age Factors; alpha-Synuclein; Analysis of Variance; Animals; Antigens, CD; Calcium-Binding Proteins; Disease Models, Animal; Gene Expression Regulation; Humans; Mice; Mice, Transgenic; Microfilament Proteins; Microglia; Microscopy, Confocal; Movement Disorders; Multiple System Atrophy; Muscle Strength; Myelin Proteolipid Protein; Nerve Tissue Proteins; Postural Balance; Sensation Disorders; Striatonigral Degeneration

Glial cytoplasmic inclusions (GCIs), commonly observed as α-synuclein (α-syn)-positive aggregates within oligodendrocytes, are the pathological hallmark of multiple system atrophy. The origin of α-syn in GCIs is uncertain; there is little evidence of endogenous α-syn expression in oligodendrocyte lineage cells, oligodendrocyte precursor cells (OPCs), and mature oligodendrocytes (OLGs). Here, based on in vitro analysis using primary rat cell cultures, we elucidated that preformed fibrils (PFFs) generated from recombinant human α-syn trigger multimerization and an upsurge of endogenous α-syn in OPCs, which is attributable to insufficient autophagic proteolysis. RNA-seq analysis of OPCs revealed that α-syn PFFs interfered with the expression of proteins associated with neuromodulation and myelination. Furthermore, we detected cytoplasmic α-syn inclusions in OLGs through differentiation of OPCs pre-incubated with PFFs. Overall, our findings suggest the possibility of endogenous α-syn accumulation in OPCs that contributes to GCI formation and perturbation of neuronal/glial support in multiple system atrophy brains.

Topics: alpha-Synuclein; Animals; Brain; Cell Culture Techniques; Cell Differentiation; Humans; Inclusion Bodies; Multiple System Atrophy; Neuroglia; Neurons; Oligodendrocyte Precursor Cells; Oligodendroglia; Rats

Dysregulation of the specialized lipid metabolism involved in myelin synthesis and maintenance by oligodendrocytes has been associated with the unique neuropathology of MSA. We hypothesized that apolipoprotein E, which is associated with neurodegeneration, may also play a role in the pathogenesis of MSA.. This study evaluated genetic associations of Apolipoprotein E alleles with risk of MSA and α-synuclein pathology, and also examined whether apolipoprotein E isoforms differentially affect α-synuclein uptake in a oligodendrocyte cell.. One hundred sixty-eight pathologically confirmed MSA patients, 89 clinically diagnosed MSA patients, and 1,277 control subjects were genotyped for Apolipoprotein E. Human oligodendrocyte cell lines were incubated with α-synuclein and recombinant human apolipoprotein E, with internalized α-synuclein imaged by confocal microscopy and cells analyzed by flow cytometry.. No significant association with risk of MSA or was observed for either Apolipoprotein E ɛ2 or ɛ4. α-Synuclein burden was also not associated with Apolipoprotein E alleles in the pathologically confirmed patients. Interestingly, in our cell assays, apolipoprotein E ɛ4 significantly reduced α-synuclein uptake in the oligodendrocytic cell line.. Despite differential effects of apolipoprotein E isoforms on α-synuclein uptake in a human oligodendrocytic cell, we did not observe a significant association at the Apolipoprotein E locus with risk of MSA or α-synuclein pathology. © 2018 International Parkinson and Movement Disorder Society.

Topics: Aged; alpha-Synuclein; Apolipoproteins E; Astrocytes; Cell Line, Transformed; Female; Genetic Testing; Genotype; Humans; Male; Multiple System Atrophy

Intracellular deposition of pathologically altered α-synuclein mostly in neurons characterises Parkinson's disease (PD), while its accumulation predominantly in oligodendrocytes is a feature of multiple system atrophy (MSA). Recently a prion-like spreading of pathologic α-synuclein has been suggested to play a role in the pathogenesis of PD and MSA. This implicates a role of protein processing systems, including lysosomes, supported also by genetic studies in PD. However, particularly for MSA, the mechanism of cell-to-cell propagation of α-synuclein is yet not fully understood. To evaluate the significance of lysosomal response, we systematically compared differently affected neuronal populations in PD, MSA, and non-diseased brains using morphometric immunohistochemistry (cathepsin D), double immunolabelling (cathepsin D/α-synuclein) laser confocal microscopy, and immunogold electron microscopy for the disease associated α-synuclein. We found that i) irrespective of the presence of neuronal inclusions, the volume density of cathepsin D immunoreactivity significantly increases in affected neurons of the pontine base in MSA brains; ii) volume density of cathepsin D immunoreactivity increases in nigral neurons in PD without inclusions and with non-ubiquitinated pre-aggregates of α-synuclein, but not in neurons with Lewy bodies; iii) cathepsin D immunoreactivity frequently colocalises with α-synuclein pre-aggregates in nigral neurons in PD; iv) ultrastructural observations confirm disease-associated α-synuclein in neuronal and astrocytic lysosomes in PD; v) lysosome-associated α-synuclein is observed in astroglia and rarely in oligodendroglia and in neurons in MSA. Our observations support a crucial role for the neuronal endosomal-lysosomal system in the processing of α-synuclein in PD. We suggest a distinct contribution of lysosomes to the pathogenesis of MSA, including the possibility of oligodendroglial and eventually neuronal uptake of exogenous α-synuclein in MSA.

Topics: Aged; Aged, 80 and over; alpha-Synuclein; Female; Humans; Lysosomes; Male; Middle Aged; Multiple System Atrophy; Parkinson Disease; Pons

The accumulation of aggregated alpha-synuclein (

Topics: Aged; alpha-Synuclein; Benzoxazoles; Brain; Female; Fluorine Radioisotopes; Humans; Immunohistochemistry; Male; Multiple System Atrophy; Neuroglia; Positron-Emission Tomography; Thiazoles

Alpha synuclein (α-syn) is central to the pathogenesis of a group of neurodegenerative disorders known as synucleinopathies, including Parkinson's disease (PD), dementia with Lewy bodies (DLB), and multiple system atrophy (MSA). Aggregation of α-syn is the pathologic hallmark of these disorders and is intimately associated with the pathogenic changes. The prion-like hypothesis postulates that the aggregated α-syn provides a template to seed the aggregation of normal α-syn and spread the pathology. Thus far, it remains unclear whether aggregated α-syn can be a useful biomarker for diagnosis and/or tracking disease progression, which is mainly due to the lack of a suitable biochemical assay. The protein misfolding cyclic amplification (PMCA) technique is known for its enormous amplification power to detect the seeding activity of protein aggregates such as prions. In this study, we adapted PMCA for detecting the seeding activity of α-syn. By extensively optimizing the PMCA parameters, we developed a protocol that is able to sensitively and quantitatively detect the seeding activity of as little as 100 attomoles (10

Topics: alpha-Synuclein; Animals; Cells, Cultured; Cerebral Cortex; Formaldehyde; Humans; Mice, Inbred C57BL; Multiple System Atrophy; Neurons; Polymerase Chain Reaction; Protein Aggregates; Protein Folding; Tissue Fixation

This study aimed to assess clinicopathologic features of transactive response DNA-binding protein of 43 kDa (TDP-43) pathology and its risk factors in multiple system atrophy (MSA).. Paraffin-embedded sections of the amygdala and basal forebrain from 186 autopsy-confirmed MSA cases were screened with immunohistochemistry for phospho-TDP-43. In cases having TDP-43 pathology, additional brain regions were assessed. Immunohistochemical and immunofluorescence double-staining and immunogold electron microscopy (IEM) were performed to evaluate colocalization of TDP-43 and α-synuclein. Genetic risk factors for TDP-43 pathology were also analysed.. Immunohistochemistry showed various morphologies of TDP-43 pathology in 13 cases (7%), such as subpial astrocytic inclusions, neuronal inclusions, dystrophic neurites, perivascular inclusions and glial cytoplasmic inclusions (GCIs). Multivariable logistic regression models revealed that only advanced age, but not concurrent Alzheimer's disease, argyrophilic grain disease or hippocampal sclerosis, was an independent risk factor for TDP-43 pathology in MSA (OR: 1.11, 95% CI: 1.04-1.19, P = 0.002). TDP-43 pathology was restricted to the amygdala in eight cases and extended to the hippocampus in two cases. The remaining three cases had widespread TDP-43 pathology. Immunohistochemical and immunofluorescence double-staining and IEM revealed colocalization of α-synuclein and TDP-43 in GCIs with granule-coated filaments. Pilot genetic studies failed to show associations between risk variants of TMEM106B or GRN and TDP-43 pathology.. TDP-43 pathology is rare in MSA and occurs mainly in the medial temporal lobe. Advanced age is a risk factor for TDP-43 pathology in MSA. Colocalization of TDP-43 and α-synuclein in GCIs suggests possible direct interaction between the two molecules.

Topics: Aged; Aged, 80 and over; alpha-Synuclein; Brain; DNA-Binding Proteins; Female; Humans; Inclusion Bodies; Male; Middle Aged; Multiple System Atrophy; Neuroglia; Neurons; Phosphorylation

The concept that abnormal protein aggregates show prion-like propagation between cells has been considered to explain the onset and progression of many neurodegenerative diseases. Indeed, both synthetic amyloid-like fibrils and pathogenic proteins extracted from patients' brains induce self-templated amplification and cell-to-cell transmission in vitro and in vivo. However, it is unclear whether exposure to exogenous prion-like proteins can potentially cause these diseases in humans. Here, we investigated in detail the prion-like seeding activities of several kinds of pathogenic α-synuclein (α-syn), including synthetic fibrils and detergent-insoluble fractions extracted from brains of patients with α-synucleinopathies. Exposure to synthetic α-syn fibrils at concentrations above 100 pg/mL caused seeded aggregation of α-syn in SH-SY5Y cells, and seeded aggregation was also observed in C57BL/6 J mice after intracerebral inoculation of at least 0.1 μg/animal. α-Syn aggregates extracted from brains of multiple system atrophy (MSA) patients showed higher seeding activity than those extracted from patients with dementia with Lewy bodies (DLB), and their potency was similar to that of synthetic α-syn fibrils. We also examined the effects of various methods that have been reported to inactivate abnormal prion proteins (PrP

Topics: alpha-Synuclein; Amyloid; Animals; Brain; Cell Line, Tumor; Dose-Response Relationship, Drug; Gene Expression Regulation; Humans; Lewy Body Disease; Mice; Mice, Inbred C57BL; Microscopy, Immunoelectron; Multiple System Atrophy; Neuroblastoma; Peptide Fragments; Prion Diseases; Transfection

Multiple System Atrophy (MSA) is a progressive neurodegenerative disease characterized by chronic neuroinflammation and widespread α-synuclein (α-syn) cytoplasmic inclusions. Neuroinflammation associated with microglial cells is typically located in brain regions with α-syn deposits. The potential link between microglial cell migration and the transport of pathological α-syn protein in MSA was investigated. Qualitative analysis via immunofluorescence of MSA cases (n = 4) revealed microglial cells bearing α-syn inclusions distal from oligodendrocytes bearing α-syn cytoplasmic inclusions, as well as close interactions between microglia and oligodendrocytes bearing α-syn, suggestive of a potential transfer mechanism between microglia and α-syn bearing cells in MSA and the possibility of microglia acting as a mobile vehicle to spread α-syn between anatomically connected brain regions. Further In vitro experiments using microglial-like differentiated THP-1 cells were conducted to investigate if microglial cells could act as potential transporters of α-syn. Monomeric or aggregated α-syn was immobilized at the centre of glass coverslips and treated with either cell free medium, undifferentiated THP-1 cells or microglial-like phorbol-12-myristate-13-acetate differentiated THP-1 cells (48 h; n = 3). A significant difference in residual immobilized α-syn density was observed between cell free controls and differentiated (p = 0.016) as well as undifferentiated and differentiated THP-1 cells (p = 0.032) when analysed by quantitative immunofluorescence. Furthermore, a significantly greater proportion of differentiated cells were observed bearing α-syn aggregates distal from the immobilized protein than their non-differentiated counterparts (p = 0.025). Similar results were observed with Highly Aggressive Proliferating Immortalised (HAPI) microglial cells, with cells exposed to aggregated α-syn yielding lower residual immobilized α-syn (p = 0.004) and a higher proportion of α-syn positive distal cells (p = 0.001) than cells exposed to monomeric α-syn. Co-treatment of THP-1 groups with the tubulin depolymerisation inhibitor, Epothilone D (EpoD; 10 nM), was conducted to investigate if inhibition of microtubule activity had an effect on cell migration and residual immobilized α-syn density. There was a significant increase in both residual immobilized α-syn between EpoD treated and non-treated differentiated cells exposed to monomeric (p = 0.037) and aggregated (p = 0.018

Topics: Aged; alpha-Synuclein; Animals; Brain; Cell Line; Cell Line, Tumor; Cell Movement; Epothilones; Humans; Microglia; Multiple System Atrophy; Rats; Tubulin Modulators

The progressive neurodegenerative disorder multiple system atrophy (MSA) is characterized by α-synuclein-positive (oligodendro-) glial cytoplasmic inclusions (GCIs). A connection between the abnormal accumulation of α-synuclein in GCIs and disease initiation and progression has been postulated. Mechanisms involved in the formation of GCIs are unclear. Abnormal uptake of α-synuclein from extracellular space, oligodendroglial overexpression of α-synuclein, and/or dysfunctional protein degradation including macroautophagy have all been discussed. In the current study, we investigated whether dysfunctional macroautophagy aggravates accumulation of extracellular α-synuclein in the oligodendroglia.. We show that oligodendroglia uptake monomeric and fibrillar extracellular α-synuclein. Blocking macroautophagy through bafilomycin A1 treatment or genetic knockdown of LC3B does not consistently change the level of incorporated α-synuclein in oligodendroglia exposed to extracellular soluble/monomeric or fibrillar α-synuclein, however leads to higher oxidative stress in combination with fibrillar α-synuclein treatment. Finally, we detected no evidence for GCI-like formation resulting from dysfunctional macroautophagy in oligodendroglia using confocal microscopy.. In summary, isolated dysfunctional macroautophagy is not sufficient to enhance abnormal accumulation of uptaken α-synuclein in vitro, but may lead to increased production of reactive oxygen species in the presence of fibrillar α-synuclein. Multiple complementary pathways are likely to contribute to GCI formation in MSA.

Topics: alpha-Synuclein; Animals; Autophagy; Brain; Humans; Inclusion Bodies; Mice, Inbred C57BL; Multiple System Atrophy; Nerve Degeneration; Oligodendroglia

Lewy bodies commonly occur in Alzheimer's disease, and Alzheimer's disease pathology is frequent in Lewy body diseases, but the burden of co-pathologies across neurodegenerative diseases is unknown. We assessed the extent of tau, amyloid-β, α-synuclein and TDP-43 proteinopathies in 766 autopsied individuals representing a broad spectrum of clinical neurodegenerative disease. We interrogated pathological Alzheimer's disease (n = 247); other tauopathies (n = 95) including Pick's disease, corticobasal disease and progressive supranuclear palsy; the synucleinopathies (n = 164) including multiple system atrophy and Lewy body disease; the TDP-43 proteinopathies (n = 188) including frontotemporal lobar degeneration with TDP-43 inclusions and amyotrophic lateral sclerosis; and a minimal pathology group (n = 72). Each group was divided into subgroups without or with co-pathologies. Age and sex matched logistic regression models compared co-pathology prevalence between groups. Co-pathology prevalence was similar between the minimal pathology group and most neurodegenerative diseases for each proteinopathy: tau was nearly universal (92-100%), amyloid-β common (20-57%); α-synuclein less common (4-16%); and TDP-43 the rarest (0-16%). In several neurodegenerative diseases, co-pathology increased: in Alzheimer's disease, α-synuclein (41-55%) and TDP-43 (33-40%) increased; in progressive supranuclear palsy, α-synuclein increased (22%); in corticobasal disease, TDP-43 increased (24%); and in neocortical Lewy body disease, amyloid-β (80%) and TDP-43 (22%) increased. Total co-pathology prevalence varied across groups (27-68%), and was increased in high Alzheimer's disease, progressive supranuclear palsy, and neocortical Lewy body disease (70-81%). Increased age at death was observed in the minimal pathology group, amyotrophic lateral sclerosis, and multiple system atrophy cases with co-pathologies. In amyotrophic lateral sclerosis and neocortical Lewy body disease, co-pathologies associated with APOE ɛ4. Lewy body disease cases with Alzheimer's disease co-pathology had substantially lower Mini-Mental State Examination scores than pure Lewy body disease. Our data imply that increased age and APOE ɛ4 status are risk factors for co-pathologies independent of neurodegenerative disease; that neurodegenerative disease severity influences co-pathology as evidenced by the prevalence of co-pathology in high Alzheimer's disease and neocortical Lewy body disease, but not intermediate

Topics: Aged; alpha-Synuclein; Alzheimer Disease; Amyotrophic Lateral Sclerosis; Apolipoprotein E4; DNA-Binding Proteins; Female; Humans; Inclusion Bodies; Lewy Bodies; Lewy Body Disease; Male; Middle Aged; Multiple System Atrophy; Neurodegenerative Diseases; Pick Disease of the Brain; Prevalence; Supranuclear Palsy, Progressive; tau Proteins; Tauopathies; TDP-43 Proteinopathies

The α-synuclein protein, encoded by SNCA, has a key role in the pathogenesis of Parkinson's disease and other synucleinopathies. Although usually sporadic, Parkinson's disease can result from inherited copy number variants in SNCA and other genes. We have hypothesized a role of somatic SNCA mutations, leading to mosaicism, in sporadic synucleinopathies. The evidence for mosaicism in healthy and diseased brain is increasing rapidly, with somatic copy number gains of APP reported in Alzheimer's brain. Here we demonstrate somatic SNCA copy number gains in synucleinopathies (Parkinson's disease and multiple system atrophy), focusing on substantia nigra. We selected sporadic cases with relatively young onset or short disease duration, and first excluded high level copy number variant mosaicism by DNA analysis using digital PCR for SNCA, and/or customized array comparative genomic hybridization. To detect low level SNCA copy number variant mosaicism, we used fluorescent in situ hybridization with oligonucleotide custom-designed probes for SNCA, validated on brain and fibroblasts with known copy number variants. We determined SNCA copy number in nigral dopaminergic neurons and other cells in frozen nigra sections from 40 cases with Parkinson's disease and five with multiple system atrophy, and 25 controls, in a blinded fashion. Parkinson's disease cases were significantly more likely than controls to have any SNCA gains in dopaminergic neurons (P = 0.0036), and overall (P = 0.0052). The average proportion of dopaminergic neurons with gains in each nigra was significantly higher in Parkinson's disease than controls (0.78% versus 0.45%; P = 0.017). There was a negative correlation between the proportion of dopaminergic neurons with gains and onset age in Parkinson's disease (P = 0.013), but not with disease duration, or age of death in cases or controls. Cases with tremor at onset were less likely to have gains (P = 0.035). All multiple system atrophy cases had gains, and the highest levels in dopaminergic neurons were in two of these cases (2.76%, 2.48%). We performed selective validation with different probes after dye swapping. All three control probes used showed minimal or no gains (≤0.1% in dopaminergic neurons). We also found occasional SNCA gains in frontal neurons of cases with Parkinson's disease, and the putamen of one multiple system atrophy case. We present evidence of somatic SNCA gains in brain, more commonly in nigral dopaminergic neurons of Parkin

Topics: Aged; alpha-Synuclein; Brain; Comparative Genomic Hybridization; DNA Copy Number Variations; Dopaminergic Neurons; Female; Gene Expression; Humans; In Situ Hybridization, Fluorescence; Male; Multiple System Atrophy; Parkinson Disease; Substantia Nigra

We aimed to determine patterns of α-synuclein (α-syn) pathology in multiple system atrophy (MSA) using 70-µm-thick sections of 20 regions of the central nervous system of 37 cases with striato-nigral degeneration (SND) and 10 cases with olivo-ponto-cerebellar atrophy (OPCA). In SND cases with the shortest disease duration (phase 1), α-syn pathology was observed in striatum, lentiform nucleus, substantia nigra, brainstem white matter tracts, cerebellar subcortical white matter as well as motor cortex, midfrontal cortex, and sensory cortex. SND with increasing duration of disease (phase 2) was characterized by involvement of spinal cord and thalamus, while phase 3 was characterized by involvement of hippocampus and amygdala. Cases with the longest disease duration (phase 4) showed involvement of the visual cortex. We observed an increasing overlap of α-syn pathology with increasing duration of disease between SND and OPCA, and noted increasingly similar regional distribution patterns of α-syn pathology. The GBA variant, p.Thr408Met, was found to have an allele frequency of 6.94% in SND cases which was significantly higher compared with normal (0%) and other neurodegenerative disease pathologies (0.74%), suggesting that it is associated with MSA. Our findings indicate that SND and OPCA show distinct early foci of α-syn aggregations, but increasingly converge with longer disease duration to show overlapping patterns of α-syn pathology.

Topics: Adult; Aged; Aged, 80 and over; alpha-Synuclein; Amyloid beta-Peptides; Brain; Cohort Studies; DNA-Binding Proteins; Female; Genetic Testing; Glucosylceramidase; Humans; Male; Middle Aged; Multiple System Atrophy; Olivopontocerebellar Atrophies; Spinal Cord; tau Proteins

Topics: alpha-Synuclein; Emotions; Humans; Multiple System Atrophy; Parkinson Disease

We aimed to characterize in vivo α-synuclein (α-syn) aggregates in skin nerves to ascertain: 1) the optimal marker to identify them; 2) possible differences between synucleinopathies that may justify the clinical variability. We studied multiple skin nerve α-syn deposits in 44 patients with synucleinopathy: 15 idiopathic Parkinson's disease (IPD), 12 dementia with Lewy Bodies (DLB), 5 pure autonomic failure (PAF) and 12 multiple system atrophy (MSA). Ten healthy subjects were used as controls. Antibodies against native α-syn, C-terminal α-syn epitopes such as phosphorylation at serine 129 (p-syn) and to conformation-specific for α-syn mature amyloid fibrils (syn-F1) were used. We found that p-syn showed the highest sensitivity and specificity in disclosing skin α-syn deposits. In MSA abnormal deposits were only found in somatic fibers mainly at distal sites differently from PAF, IPD and DLB displaying α-syn deposits in autonomic fibers mainly at proximal sites. PAF and DLB showed the highest p-syn load with a widespread involvement of autonomic skin nerve fibers.. 1) p-syn in skin nerves was the optimal marker for the in vivo diagnosis of synucleinopathies; 2) the localization and load differences of aggregates may help to identify specific diagnostic traits and support a different pathogenesis among synucleinopathies.

Topics: Aged; Aged, 80 and over; alpha-Synuclein; Amyloid; Brain; Female; Humans; Lewy Body Disease; Male; Multiple System Atrophy; Nerve Fibers; Parkinson Disease; Protein Aggregation, Pathological; Pure Autonomic Failure; Skin; Skin Diseases

Multiple system atrophy (MSA) is a neurodegenerative disease characterized by parkinsonism, ataxia, and autonomic dysfunction. Microglial infiltration is an important mediator in MSA. The nucleotide-binding domain, leucine-rich repeats-containing family, pyrin domain-containing-3 (NLRP3) inflammasome complex, comprising NLRP3, apoptotic speck protein containing a caspase recruitment domain (ASC), and cysteine aspartic acid protease 1 (Caspase 1), regulates microglial inflammation in several neurodegenerative diseases. However, its role in MSA remains unknown. This study aimed to investigate the role of the NLRP3 inflammasome in MSA. Immunohistochemical staining of postmortem brains from 11 cases of MSA, 5 of Parkinson disease, and 6 age-matched controls were assessed. The relationships among α-synuclein deposition, microglial infiltration, and NLRP3 inflammasome-related proteins (NLRP3, ASC, and Caspase 1) were quantitatively analyzed. Double-labeling immunofluorescence staining confirmed colocalization of NLRP3 inflammasome-related proteins and Cluster of Differentiation 68. We demonstrated that the density of microglia expressing NLRP3 inflammasome-related proteins was increased in the putamina of MSA cases and was significantly related to the deposition of phosphorylated α-synuclein-positive glial cytoplasmic inclusions, tyrosine hydroxylase-positive fiber loss, and gliosis of glial fibrillary acidic protein-positive astrocytes. Our study suggests that the NLRP3 inflammasome is significantly upregulated and correlates with the neurodegenerative process in MSA.

Topics: Aged; Aged, 80 and over; alpha-Synuclein; Case-Control Studies; Caspase 1; Cells, Cultured; Correlation of Data; Cytokines; Female; Glial Fibrillary Acidic Protein; Humans; Inflammasomes; Male; Multiple System Atrophy; Neuroglia; NLR Family, Pyrin Domain-Containing 3 Protein; Parkinson Disease; Putamen; Tyrosine 3-Monooxygenase; Up-Regulation

Accumulation of alpha-synuclein (ASYN) in neurons and other CNS cell types may contribute to the underlying pathology of synucleinopathies including Parkinson's disease (PD), dementia with Lewy bodies (DLB) and Multiple Systems Atrophy (MSA). In support of this hypothesis for PD, ASYN immunopositive aggregates are a prominent pathological feature of PD, and mutations and gene multiplications of human wild type (WT) ASYN cause rare familial autosomal-dominant forms of PD. Targeted therapeutics that reduce the accumulation of ASYN could prevent or slow the neurodegenerative processes in PD and other synucleinopathies. NPT200-11 is a novel small molecule inhibitor of ASYN misfolding and aggregation. The effects of NPT200-11 on ASYN neuropathology were evaluated in animal models over expressing human alpha synuclein. Longitudinal studies using retinal imaging in mice expressing a hASYN::GFP fusion protein revealed that 2 months of once daily administration of NPT200-11 (5 mg/kg IP) resulted in a time-dependent and progressive reduction in retinal ASYN pathology. The effects of NPT200-11 on ASYN pathology in cerebral cortex and on other disease-relevant endpoints was evaluated in the Line 61 transgenic mouse model overexpressing human wild type ASYN. Results from these studies demonstrated that NPT200-11 reduced alpha-synuclein pathology in cortex, reduced associated neuroinflammation (astrogliosis), normalized striatal levels of the dopamine transporter (DAT) and improved motor function. To gain insight into the relationship between dose, exposure, and therapeutic benefit pharmacokinetic studies were also conducted in mice. These studies demonstrated that NPT200-11 is orally bioavailable and brain penetrating and established target plasma and brain exposures for future studies of potential therapeutic benefit.

Topics: alpha-Synuclein; Animals; Cerebral Cortex; Disease Models, Animal; Gene Expression Regulation; Humans; Inflammation; Lewy Body Disease; Mice; Mice, Transgenic; Multiple System Atrophy; Neurons; Parkinson Disease; Piperidines; Protein Aggregation, Pathological; Protein Folding; Pyrazines; Pyrimidines; Retina

Parkinson's disease (PD) and multiple system atrophy (MSA) are neurodegenerative diseases characterized by inclusions mainly composed of α-synuclein (α-syn) aggregates. The objective of this study was to investigate if β-synuclein (β-syn) overexpression could have beneficial effects by inhibiting the aggregation of α-syn. The M83 transgenic mouse is a model of synucleinopathy, which develops severe motor symptoms associated with aggregation of α-syn. M83 neonate or adult mice were injected with adeno-associated virus vectors carrying the human β-syn gene (AAVβ-syn) or green fluorescent protein gene (AAVGFP) using different injection sites. The M83 disease was - or not - accelerated using extracts of M83 brains injected with brain extract from mouse (M83) or human (MSA) origins. AAV vectors expression was confirmed using Western blot and ELISA technics. AAV mediated β-syn overexpression did not delay the disease onset or reduce the α-syn phosphorylated at serine 129 levels detected by ELISA, regardless of the AAV injection route and the inoculation of brain extracts. Instead, a proteinase-K resistant β-syn staining was detected by immunohistochemistry, specifically in sick M83 mice overexpressing β-syn after inoculation of AAVβ-syn. This study indicated for the first time that viral vector-mediated β-syn overexpression could form aggregates in a model of synucleinopathy.

Topics: alpha-Synuclein; Animals; beta-Synuclein; Dependovirus; Disease Models, Animal; Genetic Vectors; Mice; Mice, Transgenic; Multiple System Atrophy; Neuroprotection; Transduction, Genetic

The accumulation of abnormal α-synuclein is the major histopathological feature of Lewy body disease and multiple system atrophy (MSA), which are referred to as synucleinopathies. Cytoplasmic degradation systems, such as the autophagy-lysosome and proteasome pathways, are involved in their pathogenesis. Autophagy is tightly regulated by several upstream proteins including UNC-51-like kinase 1/2, beclin1, vacuolar protein sorting-associated protein 34 and autophagy/beclin1 regulator 1 (AMBRA1). Recently, we revealed that both cortical and brainstem-type Lewy bodies were immunopositive for several upstream proteins of autophagy. Therefore, we conducted the present study to elucidate the role of upstream proteins of autophagy in the pathogenesis of MSA. Pathological and biochemical analyses using human brain samples revealed that AMBRA1 is a component of the pathological hallmarks of MSA and upstream proteins of autophagy are impaired in the MSA brain. In vitro and in vivo analyses revealed a ninefold stronger affinity of AMBRA1 with α-synuclein phosphorylated at serine 129 compared with non-phosphorylated α-synuclein. Furthermore, a weak but significant correlation between AMBRA1 overexpression and reduction of abnormal α-synuclein was observed. Silencing AMBRA1 function caused aggregates of α-synuclein in the cytoplasm of mouse primary cultured neurons, which was simulated by the treatment of Bafilomycin, an autophagy inhibitor. Our results demonstrated for the first time that AMBRA1 is a novel hub binding protein of α-synuclein and plays a central role in the pathogenesis of MSA through the degradative dynamics of α-synuclein. These results raise the possibility that molecular modulation targeting AMBRA1 can be a promising candidate for the treatment of synucleinopathies.

Topics: Adaptor Proteins, Signal Transducing; Aged; Aged, 80 and over; alpha-Synuclein; Animals; Autophagy; Brain; Green Fluorescent Proteins; HEK293 Cells; Humans; Mice, Transgenic; Microtubule-Associated Proteins; Middle Aged; Multiple System Atrophy; Proteolysis

See Stayte and Vissel (doi:10.1093/awx064) for a scientific commentary on this article. Multiple system atrophy is a fatal sporadic adult-onset neurodegenerative disorder with no symptomatic or disease-modifying treatment available. The cytopathological hallmark of multiple system atrophy is the accumulation of α-synuclein aggregates in oligodendrocytes, forming glial cytoplasmic inclusions. Impaired insulin/insulin-like growth factor-1 signalling (IGF-1) and insulin resistance (i.e. decreased insulin/IGF-1) have been reported in other neurodegenerative disorders such as Alzheimer's disease. Increasing evidence also suggests impaired insulin/IGF-1 signalling in multiple system atrophy, as corroborated by increased insulin and IGF-1 plasma concentrations in multiple system atrophy patients and reduced IGF-1 brain levels in a transgenic mouse model of multiple system atrophy. We here tested the hypothesis that multiple system atrophy is associated with brain insulin resistance and showed increased expression of the key downstream messenger insulin receptor substrate-1 phosphorylated at serine residue 312 in neurons and oligodendrocytes in the putamen of patients with multiple system atrophy. Furthermore, the expression of insulin receptor substrate 1 (IRS-1) phosphorylated at serine residue 312 was more apparent in inclusion bearing oligodendrocytes in the putamen. By contrast, it was not different between both groups in the temporal cortex, a less vulnerable structure compared to the putamen. These findings suggest that insulin resistance may occur in multiple system atrophy in regions where the neurodegenerative process is most severe and point to a possible relation between α-synuclein aggregates and insulin resistance. We also observed insulin resistance in the striatum of transgenic multiple system atrophy mice and further demonstrate that the glucagon-like peptide-1 analogue exendin-4, a well-tolerated and Federal Drug Agency-approved antidiabetic drug, has positive effects on insulin resistance and monomeric α-synuclein load in the striatum, as well as survival of nigral dopamine neurons. Additionally, plasma levels of exosomal neural-derived IRS-1 phosphorylated at serine residue 307 (corresponding to serine residue 312 in humans) negatively correlated with survival of nigral dopamine neurons in multiple system atrophy mice treated with exendin-4. This finding suggests the potential for developing this peripheral biomarker candidate as an objective

Topics: Aged; Aged, 80 and over; alpha-Synuclein; Animals; Cell Survival; Corpus Striatum; Dopaminergic Neurons; Exenatide; Female; Humans; Insulin Receptor Substrate Proteins; Insulin Resistance; Male; Mice; Mice, Transgenic; Middle Aged; Multiple System Atrophy; Neurons; Oligodendroglia; Peptides; Phosphorylation; Protein Aggregation, Pathological; Putamen; Substantia Nigra; Temporal Lobe; Venoms

We report the case of a 79-year-old Japanese woman who developed cerebellar ataxia followed by rigidity, dysautonomia and cognitive disorders, and was thus clinically diagnosed as having possible MSA with dementia. Neuropathological findings demonstrated not only olivopontocerebellar and striatonigral degeneration with frequent glial cytoplasmic inclusions (GCIs), but also degenerative changes in the parahippocampal region, accentuated in the anterior portion of perirhinal cortex, where neuronal cytoplasmic inclusions (NCIs) and NFTs were numerous while GCIs were limited. NCIs were frequent in the deep layer, whereas NFTs were more frequent in superficial cortical layers. Other hippocampal subregions including subiculum, dentate fascia and cornu ammonis were minimally involved. NCIs in the perirhinal cortex showed intense argyrophilia with the Campbell-Switzer silver impregnation method, but not argyrophilic with the Gallyas method. Most neuronal alpha-synuclein aggregates in dendrosomatic fraction formed globular/tadpole-like, and ultrastructurally comprised granular-coated fine fibrils 12-24 nm in diameter. To the best of our knowledge, alpha-synuclein-related neuronal pathology localized in the perirhinal region without hippocampal involvement has not been previously reported in MSA, and may provide clues to elucidate how neuronal pathology evolves in the hippocampal/parahippocampal regions in MSA, particularly in cases with dementia.

Topics: Aged; alpha-Synuclein; Dementia; Female; Humans; Multiple System Atrophy; Neurons

The tau PET ligand 2-((1E,3E)-4-(6-([. Of 10 pure Lewy body disease and 120 multiple system atrophy (MSA) cases in the Mayo Clinic brain bank, we selected 3 Lewy body disease and 4 MSA cases with a range of α-synuclein severity based on the quantitative analysis of α-synuclein burden. PBB3 fluorescence labeling, double or single immunostaining for α-synuclein and phospho-tau, Prussian blue staining, and in vitro autoradiography with [. PBB3 fluorescence labeled various α-synuclein lesions including Lewy bodies, Lewy neurites, spheroids, glial cytoplasmic inclusions, and neuronal cytoplasmic inclusions. Meanwhile, autoradiographic labeling with [. Given that the maximum concentration of [

Topics: Aged; Aged, 80 and over; alpha-Synuclein; Amygdala; Autoradiography; Basal Ganglia; Benzothiazoles; Female; Hippocampus; Humans; Lewy Body Disease; Male; Microscopy, Fluorescence; Middle Aged; Multiple System Atrophy; Positron-Emission Tomography; tau Proteins; Tissue Banks

To our knowledge, a comprehensive study of the survival and causes of death of persons with synucleinopathies compared with the general population has not been conducted. Understanding the long-term outcomes of these conditions may inform patients and caregivers of the expected disease duration and may help with care planning.. To compare survival rates and causes of death among patients with incident, clinically diagnosed synucleinopathies and age- and sex-matched referent participants.. This population-based study used the Rochester Epidemiology Project medical records-linkage system to identify all residents in Olmsted County, Minnesota, who received a diagnostic code of parkinsonism from 1991 through 2010. A movement-disorders specialist reviewed the medical records of each individual to confirm the presence of parkinsonism and determine the type of synucleinopathy. For each confirmed patient, an age- and sex-matched Olmsted County resident without parkinsonism was also identified.. We determined the age- and sex-adjusted risk of death for each type of synucleinopathy, the median time from diagnosis to death, and the causes of death.. Of the 461 patients with synucleinopathies, 279 (60.5%) were men, and of the 452 referent participants, 272 (60.2%) were men. From 1991 through 2010, 461 individuals received a diagnosis of a synucleinopathy (309 [67%] of Parkinson disease, 81 [17.6%] of dementia with Lewy bodies, 55 [11.9%] of Parkinson disease dementia, and 16 [3.5%] of multiple system atrophy with parkinsonism). During follow-up, 68.6% (n = 316) of the patients with synucleinopathies and 48.7% (n = 220) of the referent participants died. Patients with any synucleinopathy died a median of 2 years earlier than referent participants. Patients with multiple system atrophy with parkinsonism (hazard ratio, 10.51; 95% CI, 2.92-37.82) had the highest risk of death compared with referent participants, followed by those with dementia with Lewy bodies (hazard ratio, 3.94; 95% CI, 2.61-5.94), Parkinson disease with dementia (hazard ratio, 3.86; 95% CI, 2.36-6.30), and Parkinson disease (hazard ratio, 1.75; 95% CI, 1.39-2.21). Neurodegenerative disease was the most frequent cause of death listed on the death certificate for patients, and cardiovascular disease was the most frequent cause of death among referent participants.. Individuals with multiple system atrophy with parkinsonism, dementia with Lewy bodies, and Parkinson disease dementia have increased mortality compared with the general population. The mortality among persons with Parkinson disease is only moderately increased compared with the general population.

Topics: Aged; Aged, 80 and over; alpha-Synuclein; Cause of Death; Comorbidity; Dementia; Female; Follow-Up Studies; Humans; Lewy Body Disease; Male; Middle Aged; Minnesota; Multiple System Atrophy; Parkinson Disease; Parkinsonian Disorders

MSA is a fatal neurodegenerative disorder characterized by a combination of autonomic dysfunction, cerebellar ataxia, and l-dopa unresponsive parkinsonism. The hallmark of MSA is the accumulation of α-synuclein, forming cytoplasmic inclusions in oligodendrocytes. Adeno-associated viruses allow efficient targeting of disease-associated genes in selected cellular ensembles and have proven efficient for the neuronal overexpression of α-synuclein in the substantia nigra in the context of PD.. We aimed to develop viral-based models of MSA.. Chimeric viral vectors expressing either human wild-type α-synuclein or green fluorescent protein under the control of mouse myelin basic protein were injected in the striatum of rats and monkeys. Rats underwent a longitudinal motor assessment before histopathological analysis at 3 and 6 months.. Injection of vectors expressing α-synuclein in the striatum resulted in >80% oligodendroglial selectivity in rats and >60% in monkeys. Rats developed progressive motor deficits that were l-dopa unresponsive when assessed at 6 months. Significant loss of dopaminergic neurons occurred at 3 months, further progressing at 6 months, together with a loss of striatal neurons. Prominent α-synuclein accumulation, including phosphorylated and proteinase-K-resistant α-synuclein, was detected in the striatum and substantia nigra.. Viral-mediated oligodendroglial expression of α-synuclein allows replicating some of the key features of MSA. This flexible strategy can be used to investigate, in several species, how α-synuclein accumulation in selected oligodendroglial populations contributes to the pathophysiology of MSA and offers a new framework for preclinical validation of therapeutic strategies. © 2017 International Parkinson and Movement Disorder Society.

Topics: alpha-Synuclein; Animals; Animals, Genetically Modified; Corpus Striatum; Dependovirus; Disease Models, Animal; Dopamine Agents; Gene Expression Regulation; Haplorhini; Humans; Levodopa; Male; Multiple System Atrophy; Myelin Basic Protein; Nerve Tissue Proteins; Oligodendroglia; Phosphorylation; Psychomotor Performance; Rats; Rats, Sprague-Dawley; Substantia Nigra

Parkinson's' disease (PD) and Multiple System Atrophy (MSA) are progressive brain disorders characterized by intracellular accumulations of α-synuclein and nerve cell loss in specific brain areas. This loss causes problems with movement, balance and/or autonomic functions. Naturally occurring autoantibodies (NAbs) play potentially an important role in clearing or/and blocking circulating pathological proteins. Little is known about the functional properties of anti-α-synuclein NAbs in PD and MSA, and there have been opposing reports regarding their plasma concentrations in these disorders.. We have investigated the apparent affinity of anti-α-synuclein NAbs in plasma samples from 46 PD patients, 18 MSA patients and 41 controls using competitive enzyme-linked immunosorbent assay (ELISA) and Meso Scale Discovery (MSD) set-ups.. We found that the occurrence of high affinity anti-α-synuclein NAbs in plasma from PD patients is reduced compared to healthy controls, and nearly absent in plasma from MSA patients. Also, levels of α-synuclein/NAbs immunocomplexes is substantially reduced in plasma from both patient groups. Further, cross binding of anti-α-synuclein NAbs with β- and γ-synuclein monomers suggest, the high affinity anti-α-synuclein plasma component, seen in healthy individuals, is directed mainly against C-terminal epitopes. Furthermore, we also observed reduced occurrence of high affinity anti-phosphorylated-α-synuclein NAbs in plasma from PD and MSA patients.. One interpretation implies that these patients may have impaired ability to clear and/or block the effects of pathological α-synuclein due to insufficient/absent concentration of NAbs and as such provides a rationale for testing immune-based therapeutic strategies directed against pathological α-synuclein. Following this interpretation, we can hypothesize that high affinity autoantibodies efficiently bind and clear potentially pathological species of α-synuclein in healthy brain, and that this mechanism is impaired or absent in PD and MSA patients.

Topics: Aged; alpha-Synuclein; Autoantibodies; Brain; Enzyme-Linked Immunosorbent Assay; Female; Humans; Male; Middle Aged; Multiple System Atrophy; Parkinson Disease

Multiple system atrophy (MSA) is a horrible and unrelenting neurodegenerative disorder with an uncertain etiology and pathophysiology. MSA is a unique proteinopathy in which alpha-synuclein (α-syn) accumulates preferentially in oligodendroglia rather than neurons. Glial cytoplasmic inclusions (GCIs) of α-syn are thought to elicit changes in oligodendrocyte function, such as reduced neurotrophic support and demyelination, leading to neurodegeneration. To date, only a murine model using one of three promoters exist to study this disease. We sought to develop novel rat and nonhuman primate (NHP) models of MSA by overexpressing α-syn in oligodendroglia using a novel oligotrophic adeno-associated virus (AAV) vector, Olig001. To establish tropism, rats received intrastriatal injections of Olig001 expressing GFP. Histological analysis showed widespread expression of GFP throughout the striatum and corpus callosum with >95% of GFP+ cells co-localizing with oligodendroglia and little to no expression in neurons or astrocytes. We next tested the efficacy of this vector in rhesus macaques with intrastriatal injections of Olig001 expressing GFP. As in rats, we observed a large number of GFP+ cells in gray matter and white matter tracts of the striatum and the corpus callosum, with 90-94% of GFP+ cells co-localizing with an oligodendroglial marker. To evaluate the potential of our vector to elicit MSA-like pathology in NHPs, we injected rhesus macaques intrastriatally with Olig001 expressing the α-syn transgene. Histological analysis 3-months after injection demonstrated widespread α-syn expression throughout the striatum as determined by LB509 and phosphorylated serine-129 α-syn immunoreactivity, all of which displayed as tropism similar to that seen with GFP. As in MSA, Olig001-α-syn GCIs in our model were resistant to proteinase K digestion and caused microglial activation. Critically, demyelination was observed in the white matter tracts of the corpus callosum and striatum of Olig001-α-syn but not Olig001-GFP injected animals, similar to the human disease. These data support the concept that this vector can provide novel rodent and nonhuman primate models of MSA.

Topics: alpha-Synuclein; Animals; Astrocytes; Brain; Dependovirus; Disease Models, Animal; Endopeptidase K; Female; Genetic Vectors; Green Fluorescent Proteins; HEK293 Cells; Humans; Macaca mulatta; Male; Microglia; Multiple System Atrophy; Neurons; Oligodendroglia; Rats, Sprague-Dawley

Alpha-synuclein (α-syn) aggregation represents the pathological hallmark of α-synucleinopathies like Parkinson's disease (PD), dementia with Lewy bodies (DLB), and multiple system atrophy (MSA). Toll-like receptors (TLRs) are a family of highly conserved molecules that recognize pathogen-associated molecular patterns and define the innate immunity response. It was previously shown that TLR4 plays a role in the clearance of α-syn, suggesting that TLR4 up-regulation in microglia may be a natural mechanism to improve the clearance of α-syn. However, administration of TLR4 ligands could also lead to dangerous adverse effects associated with the induction of toxic inflammatory responses. Monophosphoryl lipid A (MPLA) is a TLR4 selective agonist and a potent inducer of phagocytosis which does not trigger strong toxic inflammatory responses as compared to lipopolysaccharide (LPS). We hypothesize that MPLA treatment will lead to increased clearance of α-syn inclusions in the brain of transgenic mice overexpressing α-syn in oligodendrocytes under the proteolipid protein promoter (PLP-α-syn mouse model of MSA), without triggering toxic cytokine release, thus leading to a general amelioration of the pathology.. Six month old PLP-α-syn mice were randomly allocated to four groups and received weekly intraperitoneal injections of MPLA (50 or 100 μg), LPS or vehicle. After a 12-week treatment period, motor behavior was assessed with the pole test. Brains and plasma samples were collected for neuropathological and immunological analysis.. Chronic systemic MPLA treatment of PLP-α-syn mice led to increased uptake of α-syn by microglial cells, a significant motor improvement, rescue of nigral dopaminergic and striatal neurons and region-specific reduction of the density of oligodendroglial α-syn cytoplasmic inclusions in the absence of a marked systemic inflammatory response.. Our findings demonstrate beneficial effects of chronic MPLA treatment in transgenic PLP-α-syn mice. MPLA appears to be an attractive therapeutic candidate for disease modification trials in MSA and related α-synucleinopathies.

Topics: alpha-Synuclein; Animals; Disease Models, Animal; Female; Lipid A; Male; Mice, Transgenic; Multiple System Atrophy; Neurons; Parkinson Disease; Substantia Nigra; Toll-Like Receptor 4

See Jellinger (doi:10.1093/awx190) for a scientific commentary on this article. The enzyme monoamine oxidases (B and A subtypes, encoded by MAOB and MAOA, respectively) are drug targets in the treatment of Parkinson's disease. Inhibitors of MAOB are used clinically in Parkinson's disease for symptomatic purposes whereas the potential disease-modifying effect of monoamine oxidase inhibitors is debated. As astroglial cells express high levels of MAOB, the enzyme has been proposed as a brain imaging marker of astrogliosis, a cellular process possibly involved in Parkinson's disease pathogenesis as elevation of MAOB in astrocytes might be harmful. Since brain monoamine oxidase status in Parkinson's disease is uncertain, our objective was to measure, by quantitative immunoblotting in autopsied brain homogenates, protein levels of both monoamine oxidases in three different degenerative parkinsonian disorders: Parkinson's disease (n = 11), multiple system atrophy (n = 11), and progressive supranuclear palsy (n = 16) and in matched controls (n = 16). We hypothesized that if MAOB is 'substantially' localized to astroglial cells, MAOB levels should be generally associated with standard astroglial protein measures (e.g. glial fibrillary acidic protein). MAOB levels were increased in degenerating putamen (+83%) and substantia nigra (+10%, non-significant) in multiple system atrophy; in caudate (+26%), putamen (+27%), frontal cortex (+31%) and substantia nigra (+23%) of progressive supranuclear palsy; and in frontal cortex (+33%), but not in substantia nigra of Parkinson's disease, a region we previously reported no increase in astrocyte protein markers. Although the magnitude of MAOB increase was less than those of standard astrocytic markers, significant positive correlations were observed amongst the astrocyte proteins and MAOB. Despite suggestions that MAOA (versus MAOB) is primarily responsible for metabolism of dopamine in dopamine neurons, there was no loss of the enzyme in the parkinsonian substantia nigra; instead, increased nigral levels of a MAOA fragment and 'turnover' of the enzyme were observed in the conditions. Our findings provide support that MAOB might serve as a biochemical imaging marker, albeit not entirely specific, for astrocyte activation in human brain. The observation that MAOB protein concentration is generally increased in degenerating brain areas in multiple system atrophy (especially putamen) and in progressive supranuclear palsy, but no

Topics: Adolescent; Adult; alpha-Synuclein; Brain; Case-Control Studies; Caudate Nucleus; Dopamine; Female; Frontal Lobe; Glial Fibrillary Acidic Protein; Humans; Isoenzymes; Male; Middle Aged; Monoamine Oxidase; Multiple System Atrophy; Nerve Degeneration; Parkinson Disease; Peptide Fragments; Phosphopyruvate Hydratase; Putamen; Substantia Nigra; Supranuclear Palsy, Progressive; Tubulin; Young Adult

The aim of this study was to identify early foci of α-synuclein (α-syn pathology) accumulation, subsequent progression and neurodegeneration in multiple system atrophy of the cerebellar type (MSA-C).. We analysed 70-μm-thick sections of 10 cases with MSA-C and 24 normal controls.. MSA-C cases with the lowest burden of pathology showed α-syn glial cytoplasmic inclusions (GCIs) in the cerebellum as well as in medullary and pontine cerebellar projections. Cerebellar pathology was highly selective and severely involved subcortical white matter, whereas deep white matter and granular layer were only mildly affected and the molecular layer was spared. Loss of Purkinje cells increased with disease duration and was associated with neuronal and axonal abnormalities. Neocortex, basal ganglia and spinal cord became consecutively involved with the increasing burden of α-syn pathology, followed by hippocampus, amygdala, and, finally, the visual cortex. GCIs were associated with myelinated axons, and the severity of GCIs correlated with demyelination.. Our findings indicate that cerebellar subcortical white matter and cerebellar brainstem projections are likely the earliest foci of α-syn pathology in MSA-C, followed by involvement of more widespread regions of the central nervous system and neurodegeneration with disease progression.

Topics: Aged; alpha-Synuclein; Central Nervous System; Cerebellum; Disease Progression; Female; Humans; Male; Middle Aged; Multiple System Atrophy; Nerve Degeneration

Neurodegenerative diseases are a very diverse group of disorders but they share some common mechanisms such as abnormally misfolded proteins with prion-like propagation and aggregation. Creutzfeldt-Jakob disease (CJD) is the most prevalent prion disease in humans. In the sporadic form of CJD the only known risk factor is the codon 129 polymorphism. Recent reports suggested that α-synuclein in multiple system atrophy (MSA) has similar pathogenic mechanisms as the prion protein. Here we present 1 Italian family with MSA and prion disease. Also, cases of concurrent MSA and prion pathology in the same individual or family suggest the possibility of molecular interaction between prion protein and α-synuclein in the process of protein accumulation and neurodegeneration, warranting further investigations. We assessed the PRNP gene by whole-exome sequencing in 264 pathologically confirmed MSA cases and 462 healthy controls to determine whether the 2 diseases share similar risk factors. We then analyzed codon 129 polymorphism by Sanger sequencing and compared with previously published results in sporadic CJD. Homozygosity at codon 129 was present in 50% of pathologically confirmed MSA cases and in 58% of normal controls (odds ratio, 0.7 (95% confidence interval of 0.5-0.9)) compared with 88.2% in sporadic CJD. Our data show that the homozygous state of position 129 in the PRNP is not a risk factor for MSA. No other variants in the PRNP gene were associated with increased risk for MSA.

Topics: alpha-Synuclein; Brain; Codon; Epistasis, Genetic; Exome; Female; Genetic Association Studies; Homozygote; Humans; Magnetic Resonance Imaging; Male; Multiple System Atrophy; Polymorphism, Genetic; Prion Proteins; Risk Factors; Sequence Analysis, DNA

The objectives of this study were to elucidate any potential association between α-synuclein pathology and cognitive impairment and to determine the profile of cognitive impairment in multiple system atrophy (MSA) patients. To do this, we analyzed the clinical and pathologic features in autopsy-confirmed MSA patients.. We retrospectively reviewed medical records, including neuropsychological test data, in 102 patients with autopsy-confirmed MSA in the Mayo Clinic brain bank. The burden of glial cytoplasmic inclusions and neuronal cytoplasmic inclusions were semiquantitatively scored in the limbic regions and middle frontal gyrus. We also assessed concurrent pathologies potentially causing dementia including Alzheimer's disease, hippocampal sclerosis, and cerebrovascular pathology.. Of 102 patients, 33 (32%) were documented to have cognitive impairment. Those that received objective testing, deficits primarily in processing speed and attention/executive functions were identified, which suggests a frontal-subcortical pattern of dysfunction. Of these 33 patients with cognitive impairment, 8 patients had concurrent pathologies of dementia. MSA patients with cognitive impairment had a greater burden of neuronal cytoplasmic inclusions in the dentate gyrus than patients without cognitive impairment, both including and excluding patients with concurrent pathologies of dementia.. The cognitive deficits observed in this study were more evident on neuropsychological assessment than with cognitive screens. Based on these findings, we recommend that clinicians consider more in-depth neuropsychological assessments if patients with MSA present with cognitive complaints. Although we did not identify the correlation between cognitive deficits and responsible neuroanatomical regions, a greater burden of neuronal cytoplasmic inclusions in the limbic regions was associated with cognitive impairment in MSA. © 2016 International Parkinson and Movement Disorder Society.

Topics: Aged; alpha-Synuclein; Cognitive Dysfunction; Dementia; Female; Humans; Male; Middle Aged; Multiple System Atrophy; Retrospective Studies

Topics: Aged; alpha-Synuclein; Aneuploidy; Female; Humans; Male; Multiple System Atrophy; Neurons

Parkinson disease (PD) is a highly prevalent and incurable neurodegenerative disease associated with the accumulation of misfolded α-synuclein (αSyn) aggregates. An important problem in this disease is the lack of a sensitive, specific, and noninvasive biochemical diagnosis to help in clinical evaluation, monitoring of disease progression, and early differential diagnosis from related neurodegenerative diseases.. To develop a novel assay with high sensitivity and specificity to detect small quantities of αSyn aggregates circulating in cerebrospinal fluid (CSF) of patients affected by PD and related synucleinopathies.. The strategy evaluated in this proof-of-concept study uses the protein misfolding cyclic amplification (PMCA) technology that detects minute amounts of misfolded oligomers by taking advantage of their ability to nucleate further aggregation, enabling a very high amplification of the signal. The technology was first adapted with synthetic αSyn oligomers prepared in vitro and used to screen in 2 blinded cohorts of CSF samples from German and Japanese patients with PD (n = 76) and individuals serving as controls affected by other neurologic disorders (n = 65), neurodegenerative diseases (n = 18), and Alzheimer disease (n = 14). The kinetics of αSyn aggregation were measured by αSyn-PMCA in the presence of CSF samples from the participants to detect αSyn oligomeric seeds present in this biological fluid. The assays were conducted from November 15, 2013, to August 28, 2015.. Kinetic parameters correlated with disease severity at the time of sample collection, measured by the Hoehn and Yahr scale, with the lowest grade indicating unilateral involvement with minimal or no functional impairment, and the highest grade defining patients with complete confinement to wheelchair or bed.. Studies with synthetic αSyn aggregates showed that αSyn-PMCA enabled to detect as little as 0.1 pg/mL of αSyn oligomers. The αSyn-PMCA signal was directly proportional to the amount of αSyn oligomers added to the reaction. A blinded study of CSF samples correctly identified patients affected by PD with an overall sensitivity of 88.5% (95% CI, 79.2%-94.6%) and specificity of 96.9% (95% CI, 89.3%-99.6%). The αSyn-PMCA results for different patients correlated with the severity of the clinical symptoms of PD (Japanese cohort: rs = -0.54, P = .006; German cohort: rs = -0.36, P = .02).. The findings suggest that detection of αSyn oligomers by αSyn-PMCA in the CSF of patients affected by PD may offer a good opportunity for a sensitive and specific biochemical diagnosis of the disease. Further studies are needed to investigate the usefulness of αSyn-PMCA to monitor disease progression and for preclinical identification of patients who may develop PD.

Topics: alpha-Synuclein; Amyloid beta-Peptides; Biochemical Phenomena; Diagnostic Tests, Routine; Female; Humans; In Vitro Techniques; Lewy Body Disease; Male; Multiple System Atrophy; Outcome Assessment, Health Care; Parkinson Disease; Peptide Fragments; Predictive Value of Tests; Protein Aggregation, Pathological; Proteostasis Deficiencies; Retrospective Studies; Sensitivity and Specificity; Severity of Illness Index; tau Proteins

Multiple system atrophy (MSA) is a fatal neurodegenerative disorder characterized by the pathological accumulation of alpha-synuclein (α-syn) in oligodendrocytes. Therapeutic efforts to stop or delay the progression of MSA have yielded suboptimal results in clinical trials, and there are no efficient treatments currently available for MSA patients. We hypothesize that combining therapies targeting different aspects of the disease may lead to better clinical outcomes. To test this hypothesis, we combined the use of a single-chain antibody targeting α-syn modified for improved central nervous system penetration (CD5-D5) with an unconventional anti-inflammatory treatment (lenalidomide) in the myelin basic protein (MBP)-α-syn transgenic mouse model of MSA. While the use of either CD5-D5 or lenalidomide alone had positive effects on neuroinflammation and/or α-syn accumulation in this mouse model of MSA, the combination of both approaches yielded better results than each single treatment. The combined treatment reduced astrogliosis, microgliosis, soluble and aggregated α-syn levels, and partially improved behavioral deficits in MBP-α-syn transgenic mice. These effects were associated with an activation of the Akt signaling pathway, which may mediate cytoprotective effects downstream tumor necrosis factor alpha (TNFα). These results suggest that a strategic combination of treatments may improve the therapeutic outcome in trials for MSA and related neurodegenerative disorders.

Topics: alpha-Synuclein; Animals; Anti-Inflammatory Agents; Disease Models, Animal; Gliosis; Humans; Immunotherapy; Lenalidomide; Mice, Transgenic; Multiple System Atrophy; Proto-Oncogene Proteins c-akt; Signal Transduction; Single-Chain Antibodies; Thalidomide; Tumor Necrosis Factor-alpha

Topics: Aged; Aged, 80 and over; alpha-Synuclein; Astrocytes; Female; Humans; Male; Middle Aged; Multiple System Atrophy

The histological hallmark of multiple system atrophy (MSA) is accumulation of phosphorylated α-synuclein in oligodendrocytes. However, it is uncertain whether phosphorylated α-synuclein accumulates in astrocytes of MSA patients. We immunohistochemically examined the frontal and temporal lobes, basal ganglia, cerebellum, brainstem and spinal cord of patients with MSA (n = 15) and Lewy body disease (n = 20), and also in control subjects (n = 20). Accumulation of abnormally phosphorylated and aggregated α-synuclein was found in subpial and periventricular astrocytes in six of the 15 patients with MSA (40%). The structures were confined to the subpial surface of the ventro-lateral part of the spinal cord and brainstem, as well as the subependymal region of the lateral ventricles. They were not visualized by Gallyas-Braak staining, and were immunonegative for ubiquitin and p62. Immunoelectron microscopy revealed that the phosphorylated α-synuclein-immunoreactive structures in astrocytes were non-fibrillar and associated with granular and vesicular structures. The extent of phosphorylated α-synuclein-immunoreactive astrocytes was correlated with disease duration. No such structures were found in Lewy body disease or controls. Accumulation of phosphorylated α-synuclein can occur in subpial and periventricular astrocytes in patients with MSA, especially in those with a long disease duration.

Topics: Aged; alpha-Synuclein; Astrocytes; Brain; Female; Humans; Immunohistochemistry; Inclusion Bodies; Lewy Body Disease; Male; Microscopy, Immunoelectron; Middle Aged; Multiple System Atrophy; Phosphorylation; Spinal Cord; Time Factors

Topics: alpha-Synuclein; Brain; Female; Humans; Male; Multiple System Atrophy; Nerve Fibers; Parkinson Disease; Skin

Topics: alpha-Synuclein; Brain; Female; Humans; Male; Multiple System Atrophy; Nerve Fibers; Parkinson Disease; Skin

Together with Parkinson's disease (PD) and dementia with Lewy bodies, multiple system atrophy (MSA) is a member of a diverse group of neurodegenerative disorders termed α-synucleinopathies. Previously, it has been shown that α-synuclein, parkin, and synphilin-1 display disease-specific transcription patterns in frontal cortex in PD, dementia with Lewy bodies, and MSA, and thus may mediate the development of α-synucleinopathies. In this study, the differential expression of α-synuclein isoforms on transcriptional and translational levels was ascertained in MSA patients in comparison with PD cases and normal controls using isoform-specific primers and exon-specific antibodies in substantia nigra, striatum, cerebellar cortex, and nucleus dentatus. These regions are severely affected by α-synuclein pathology and neurodegeneration. Furthermore, we have also investigated transcript levels for parkin and synphilin-1 isoforms. In MSA brains, α-synuclein140 and α-synuclein 112 isoform levels were significantly increased, whereas levels of the α-synuclein 126 isoform were decreased in the substantia nigra, striatum, cerebellar cortex, and nucleus dentatus versus controls. Moreover, in MSA cases, we showed increased levels of parkin isoforms lacking the N-terminal ubiquitin-like domain and an aggregation-prone synphilin-1A isoform that causes neuronal toxicity in MSA. In PD brains, parkin transcript variant 3, 7, and 11 were significantly and specifically over-expressed in the striatum and cerebellar cortex, together with synphilin-1A and 1C. The changes of isoform expression profiles in neurodegenerative diseases suggest alterations in the regulation of transcription and/or splicing events, leading to regional/cellular events that may be important for the highly increased aggregation of α-synuclein in the brain. We report differential expression of α-synuclein, parkin, and synphilin-1 isoforms in multiple system atrophy (MSA) versus Parkinson's disease and normal control brains. We have focused on brain regions that are severely affected by α-synuclein pathology and neurodegeneration in MSA. The reported changes of isoform expression profiles suggest alterations in the regulation of transcription that may be important for aggregation of α-synuclein in the brain.

Topics: Aged; Aged, 80 and over; alpha-Synuclein; Brain; Carrier Proteins; Female; Humans; Male; Middle Aged; Multiple System Atrophy; Nerve Tissue Proteins; Parkinson Disease; Protein Isoforms; Ubiquitin-Protein Ligases

Gastric and colonic alpha-synuclein immunoreactivity has been reported in patients with Parkinson's disease (PD). However, enteric alpha-synuclein also has been reported in healthy individuals.. We aimed to investigate the utility of alpha-synuclein immunoreactivity from gastric and colonic mucosal tissues obtained by routine endoscopy to detect PD, and to correlate the pathological burden of alpha-synuclein with motor and nonmotor features of PD.. We recruited 104 study subjects, consisting of 38 patients with PD, 13 patients with probable multiple system atrophy (MSA), and 53 healthy controls. Gastric and colonic mucosal tissues obtained by endoscopic gastroduodenoscopy and colonoscopy were assessed using alpha-synuclein immunohistochemistry. Detailed motor and nonmotor features of PD were correlated with enteric alpha-synuclein immunoreactivity.. No difference was seen in the enteric α-SYN immunoreactivity among patients with PD (31.6% for stomach and 10.4% for colon), patients with MSA (40.0% for stomach and 8.0% for colon), and healthy controls (33.3% for stomach and 18.5% for colon). The frequency of positive alpha-synuclein immunoreactivity was higher in gastric biopsy tissues than in colonic biopsy tissues in all of the study groups (P < 0.05). No significant correlation was found between the presence of alpha-synuclein immunoreactivity and the motor and nonmotor features of PD.. The presence of alpha-synuclein immunoreactivity in gastric and colonic mucosa was detected in a similar manner in patients with PD, patients with MSA, and controls, thus suggesting a limited role of enteric mucosal alpha-synuclein as a diagnostic biomarker for PD. Future studies are warranted to detect pathological alpha-synuclein strains.

Topics: Aged; alpha-Synuclein; Biomarkers; Female; Gastric Mucosa; Humans; Intestinal Mucosa; Male; Middle Aged; Multiple System Atrophy; Parkinson Disease

Topics: alpha-Synuclein; Animals; Female; Humans; Male; Multiple System Atrophy; Parkinsonian Disorders; Prions

Topics: alpha-Synuclein; Congresses as Topic; Humans; Multiple System Atrophy; Parkinson Disease; Societies, Medical

Multiple system atrophy (MSA) is a sporadic neurodegenerative disease. The major pathological hallmark of MSA is the accumulation of α-synuclein in oligodendrocytes. In contrast to Parkinson's disease no definitive familial etiology for MSA has been determined. Yet, there is a growing body of evidence that perturbation of transcriptional processes leads to MSA pathology. Here we present the results of the first ribosomal-depleted strand-specific RNA-sequencing profile of the MSA brain frontal cortex tissue. Among the 123 differentially expressed genes over 50% were categorized as putative long intervening non-coding RNAs (lincRNAs). Along with the dysregulation of the non-coding portion of the transcriptome, the expression of protein coding genes was also affected, including serpin peptidase inhibitor, clade A (alpha-1 antiproteinase, antitrypsin), member 3 (SERPINA3), interleukin 1 receptor-like 1 (IL1RL1) and hemoglobin, beta (HBB). Also of interest was the alternative splicing of SNCA, along with the presence of an antisense transcript overlapping the 3' exon of SNCA. Moreover, we demonstrate widespread antisense transcription throughout the frontal cortex that is largely not affected by MSA-specific neurodegenerative process. MSA causes a large disruption of lincRNAs in the human brain along with protein coding genes related to iron metabolism and immune response regulation. Most of the lincRNAs specific for MSA were novel. Hence our study uncovers another level of complexity in transcriptional pathology of MSA.

Topics: Aged; Aged, 80 and over; alpha-Synuclein; Female; Frontal Lobe; Gene Expression Profiling; Humans; Immunohistochemistry; Male; Middle Aged; Multiple System Atrophy; RNA, Long Noncoding; Transcriptome

Multiple system atrophy (MSA) is a fatal rapidly progressive α-synucleinopathy, characterized by α-synuclein accumulation in oligodendrocytes. It is accepted that the pathological α-synuclein accumulation in the brain of MSA patients plays a leading role in the disease process, but little is known about the events in the early stages of the disease. In this study we aimed to define potential roles of the miRNA-mRNA regulatory network in the early pre-motor stages of the disease, i.e., downstream of α-synuclein accumulation in oligodendroglia, as assessed in a transgenic mouse model of MSA. We investigated the expression patterns of miRNAs and their mRNA targets in substantia nigra (SN) and striatum, two brain regions that undergo neurodegeneration at a later stage in the MSA model, by microarray and RNA-seq analysis, respectively. Analysis was performed at a time point when α-synuclein accumulation was already present in oligodendrocytes at neuropathological examination, but no neuronal loss nor deficits of motor function had yet occurred. Our data provide a first evidence for the leading role of gene dysregulation associated with deficits in immune and inflammatory responses in the very early, non-symptomatic disease stages of MSA. While dysfunctional homeostasis and oxidative stress were prominent in SN in the early stages of MSA, in striatum differential gene expression in the non-symptomatic phase was linked to oligodendroglial dysfunction, disturbed protein handling, lipid metabolism, transmembrane transport and altered cell death control, respectively. A large number of putative miRNA-mRNAs interaction partners were identified in relation to the control of these processes in the MSA model. Our results support the role of early changes in the miRNA-mRNA regulatory network in the pathogenesis of MSA preceding the clinical onset of the disease. The findings thus contribute to understanding the disease process and are likely to pave the way towards identifying disease biomarkers for early diagnosis of MSA.

Topics: alpha-Synuclein; Animals; Corpus Striatum; Disease Models, Animal; Humans; Mice; Mice, Transgenic; MicroRNAs; Multiple System Atrophy; Oligodendroglia; RNA, Messenger

Multiple system atrophy (MSA) is a rare atypical parkinsonian disorder characterized by a rapidly progressing clinical course and at present without any efficient therapy. Neuropathologically, myelin loss and neurodegeneration are associated with α-synuclein accumulation in oligodendrocytes, but underlying pathomechanisms are poorly understood. Here, we analyzed the impact of oligodendrocytic α-synuclein on the formation of myelin sheaths to define a potential interventional target for MSA. Post-mortem analyses of MSA patients and controls were performed to quantify myelin and oligodendrocyte numbers. As pre-clinical models, we used transgenic MSA mice, a myelinating stem cell-derived oligodendrocyte-neuron co-culture, and primary oligodendrocytes to determine functional consequences of oligodendrocytic α-synuclein overexpression on myelination. We detected myelin loss accompanied by preserved or even increased numbers of oligodendrocytes in post-mortem MSA brains or transgenic mouse forebrains, respectively, indicating an oligodendrocytic dysfunction in myelin formation. Corroborating this observation, overexpression of α-synuclein in primary and stem cell-derived oligodendrocytes severely impaired myelin formation, defining a novel α-synuclein-linked pathomechanism in MSA. We used the pro-myelinating activity of the muscarinic acetylcholine receptor antagonist benztropine to analyze the reversibility of the myelination deficit. Transcriptome profiling of primary pre-myelinating oligodendrocytes demonstrated that benztropine readjusts myelination-related processes such as cholesterol and membrane biogenesis, being compromised by oligodendrocytic α-synuclein. Additionally, benztropine restored the α-synuclein-induced myelination deficit of stem cell-derived oligodendrocytes. Strikingly, benztropine also ameliorated the myelin deficit in transgenic MSA mice, resulting in a prevention of neuronal cell loss. In conclusion, this study defines the α-synuclein-induced myelination deficit as a novel and crucial pathomechanism in MSA. Importantly, the reversible nature of this oligodendrocytic dysfunction opens a novel avenue for an intervention in MSA.

Topics: alpha-Synuclein; Animals; Antiparkinson Agents; Benztropine; Brain; Cell Death; Cells, Cultured; Coculture Techniques; Disease Models, Animal; Dose-Response Relationship, Drug; Gliosis; Male; Mice, Transgenic; Multiple System Atrophy; Neurons; Oligodendroglia; Rats, Wistar; Stem Cells; Transcriptome

Similar to Parkinson disease, multiple system atrophy (MSA) presents neuropathologically with nigral neuronal loss; however, the hallmark intracellular α-synuclein (αSyn) accumulation in MSA affects typically oligodendrocytes to form glial cytoplasmic inclusions. The underlying pathogenic mechanisms remain unclear. As MSA is predominantly sporadic, epigenetic mechanisms may play a role. We tested the effects of the pan-histone deacetylase inhibitor (HDACi) sodium phenylbutyrate in aged mice overexpressing αSyn under the control of the proteolipid protein promoter (PLP-αSyn) designed to model MSA and characterized by αSyn accumulation in oligodendrocytes and nigral neurodegeneration. HDACi improved motor behavior and survival of nigral neurons in PLP-αSyn mice. Furthermore, HDACi reduced the density of oligodendroglial αSyn aggregates, which correlated with the survival of nigral neurons in PLP-αSyn mice. For the first time, we suggest a role of HDACi in the pathogenesis of MSA-like neurodegeneration and support the future development of selective HDACi for MSA therapy.

Topics: Aging; alpha-Synuclein; Animals; Brain; Disease Models, Animal; Epigenesis, Genetic; Female; Gait Disorders, Neurologic; Male; Mice; Mice, Inbred C57BL; Mice, Transgenic; Multiple System Atrophy; Myelin Proteolipid Protein; Neuroglia; Neurons; Neuroprotective Agents; Phenylbutyrates; Promoter Regions, Genetic; Protein Deglycase DJ-1

Multiple system atrophy (MSA) is a rare progressive neurodegenerative disorder. MSA was originally considered exclusively sporadic but reports of association with genes such as SNCA, COQ2 and LRRK2 have demonstrated that there is a genetic contribution to the disease. MAPT has been associated with several neurodegenerative diseases and we previously reported a protective association of the MAPT H2 haplotype with MSA in 61 pathologically confirmed cases.. In the present study, we assessed the full MAPT haplotype diversity in MSA patients using six MAPT tagging SNPs. We genotyped a total of 127 pathologically confirmed MSA cases, 86 patients with clinically diagnosed MSA and 1312 controls.. We identified four significant association signals in our pathologically confirmed cases, two from the protective haplotypes H2 (MSA:16.2%,. 22.7%, p = 0.024) and H1E (MSA:3.0%,. 9.0%, p = 0.014), and two from the rare risk haplotypes H1x (MSA:3.7%,. 1.3%, p = 0.030) and H1J (MSA:3.0%,. 0.9%, p = 0.021). We evaluated the association of MSA subtypes with the common protective H2 haplotype and found a significant difference with controls for MSA patients with some degree of MSA-C (MSA-C or MSA-mixed), for whom H2 occurred in only 8.6% of patients in our pathologically confirmed series (P < 0.0001).. Our findings provide further evidence that MAPT variation is associated with risk of MSA. Interestingly, our results suggest a greater effect size in the MSA-C compared to MSA-P for H2. Additional genetic studies in larger pathologically confirmed MSA series and meta-analytic studies will be needed to fully assess the role of MAPT and other genes in MSA.

Topics: Aged; Aged, 80 and over; alpha-Synuclein; Female; Genetic Predisposition to Disease; Genotype; Haplotypes; Humans; Male; Middle Aged; Multiple System Atrophy; Parkinson Disease; Polymorphism, Single Nucleotide; Risk; tau Proteins

Multiple system atrophy (MSA) is a sporadic orphan neurodegenerative disorder. No treatment is currently available to slow down the aggressive neurodegenerative process, and patients die within a few years after disease onset. The cytopathological hallmark of MSA is the accumulation of alpha-synuclein (α-syn) aggregates in affected oligodendrocytes. Several studies point to α-syn oligomerization and aggregation as a mediator of neurotoxicity in synucleinopathies including MSA. C-terminal truncation by the inflammatory protease caspase-1 has recently been implicated in the mechanisms that promote aggregation of α-syn in vitro and in neuronal cell models of α-syn toxicity. We present here an in vivo proof of concept of the ability of the caspase-1 inhibitor prodrug VX-765 to mitigate α-syn pathology and to mediate neuroprotection in proteolipid protein α-syn (PLP-SYN) mice, a transgenic mouse model of MSA. PLP-SYN and age-matched wild-type mice were treated for a period of 11 wk with VX-765 or placebo. VX-765 prevented motor deficits in PLP-SYN mice compared with placebo controls. More importantly, VX-765 was able to limit the progressive toxicity of α-syn aggregation by reducing its load in the striatum of PLP-SYN mice. Not only did VX-765 reduce truncated α-syn, but it also decreased its monomeric and oligomeric forms. Finally, VX-765 showed neuroprotective effects by preserving tyrosine hydroxylase-positive neurons in the substantia nigra of PLP-SYN mice. In conclusion, our results suggest that VX-765, a drug that was well tolerated in a 6 wk-long phase II trial in patients with epilepsy, is a promising candidate to achieve disease modification in synucleinopathies by limiting α-syn accumulation.

Topics: alpha-Synuclein; Animals; Caspase 1; Clinical Trials as Topic; Corpus Striatum; Dipeptides; Disease Models, Animal; Gene Expression Regulation; Humans; Mice; Mice, Transgenic; Multiple System Atrophy; Neurons; Oligodendroglia; para-Aminobenzoates; Protein Aggregates; Proteolysis; Signal Transduction; Substantia Nigra; Tyrosine 3-Monooxygenase

A single amyloidogenic protein is implicated in multiple neurological diseases and capable of generating a number of aggregate "strains" with distinct structures. Among the amyloidogenic proteins, α-synuclein generates multiple patterns of proteinopathies in a group of diseases, such as Parkinson disease (PD), dementia with Lewy bodies (DLB), and multiple system atrophy (MSA). However, the link between specific conformations and distinct pathologies, the key concept of the strain hypothesis, remains elusive. Here we show that in the presence of bacterial endotoxin, lipopolysaccharide (LPS), α-synuclein generated a self-renewable, structurally distinct fibril strain that consistently induced specific patterns of synucleinopathies in mice. These results suggest that amyloid fibrils with self-renewable structures cause distinct types of proteinopathies despite the identical primary structure and that exposure to exogenous pathogens may contribute to the diversity of synucleinopathies.

Topics: alpha-Synuclein; Amyloid; Animals; Cells, Cultured; Female; Humans; Lewy Body Disease; Lipopolysaccharides; Mice; Mice, Inbred C57BL; Microglia; Multiple System Atrophy; Neurons; Parkinson Disease; Protein Aggregates; Protein Structure, Tertiary; Protein Transport

Microglia in the brain show distinctive phenotypes that serve different functions. In particular, M2-polarized microglia are anti-inflammatory and phagocytic cells that serve a restorative function. In this study, we investigated whether mesenchymal stem cells (MSCs) enhance the phagocytic clearance of α-synuclein via M2 microglia polarization, and thereby exert neuroprotective effects in α-synuclein-enriched experimental models and patients with multiple system atrophy (MSA). Treatment of BV2 cells with α-synuclein induced an inflammatory phenotype, whereas co-culture of α-synuclein-treated BV2 cells with MSCs induced an anti-inflammatory M2 phenotype, with decreased α-synuclein levels and increased lysosomal activity, leading to greater viability of neuronal cells co-cultured with BV2 cells. Using IL-4 receptor siRNA in BV2 cells and IL-4 siRNA in MSCs, we found that M2 microglia polarization was induced by IL-4 secreted from MSCs. In α-synuclein-inoculated mice, MSC treatment induced M2 microglia polarization decreased α-synuclein levels, and had a prosurvival effect on neurons. Using IL-4 and IL-4 receptor knockout mice, we further confirmed that IL-4 secreted from MSCs induced phagocytic clearance of α-synuclein through M2 microglia polarization. Next, we found that the cerebrospinal fluid (CSF) from MSC-transplanted MSA patients induced microglia M2 polarization and had a prosurvival effect via enhanced clearance of α-synuclein in α-synuclein-treated BV2 cells. Finally, a serial CSF study demonstrated that changes in oligomeric α-synuclein from baseline to 1-year follow-up were greater in the CSF of MSC-transplanted MSA patients than in placebo-transplanted MSA patients. These findings indicate that MSCs exert a neuroprotective effect via the clearance of extracellular α-synuclein by controlling microglia M2 polarization, suggesting that MSCs could be used as a disease-modifying therapy for patients with α-synucleinopathies.

Topics: alpha-Synuclein; Animals; Anti-Inflammatory Agents; Cell Line; Cell Polarity; Coculture Techniques; Cytokines; Disease Models, Animal; Gene Expression Regulation; Humans; Interleukin-4; Male; Mesenchymal Stem Cells; Mice; Mice, Inbred C57BL; Mice, Knockout; Microglia; Multiple System Atrophy; Neuroprotective Agents; Parkinsonian Disorders; Phosphopyruvate Hydratase

To identify genetic variants that play a role in the pathogenesis of multiple system atrophy (MSA), we undertook a genome-wide association study (GWAS).. We performed a GWAS with >5 million genotyped and imputed single nucleotide polymorphisms (SNPs) in 918 patients with MSA of European ancestry and 3,864 controls. MSA cases were collected from North American and European centers, one third of which were neuropathologically confirmed.. We found no significant loci after stringent multiple testing correction. A number of regions emerged as potentially interesting for follow-up at p < 1 × 10. We present a GWAS in MSA. We have identified several potentially interesting gene loci, including the MAPT locus, whose significance will have to be evaluated in a larger sample set. Common genetic variation in SNCA and COQ2 does not seem to be associated with MSA. In the future, additional samples of well-characterized patients with MSA will need to be collected to perform a larger MSA GWAS, but this initial study forms the basis for these next steps.

Topics: Alkyl and Aryl Transferases; alpha-Synuclein; Brain; Cohort Studies; Europe; Genetic Loci; Genome-Wide Association Study; Genotyping Techniques; Humans; Multiple System Atrophy; Polymorphism, Single Nucleotide; RNA, Messenger; United States; White People

Accumulation of α-synuclein in multiple system atrophy (MSA) affects medullary autonomic and respiratory control areas, including the rostral ventrolateral medulla and raphe nuclei. Relative neuronal vulnerability and its relationship to α-synuclein accumulation in these areas are unknown. The aim of this study was to determine the extent of loss of adrenergic neurons in the rostral ventrolateral medulla and serotonergic neurons in the ventrolateral medulla and raphe nuclei and its relationship with α-synuclein accumulation.. Medullary sections from 7 MSA and 6 control subjects were processed for tyrosine hydroxylase, tryptophan hydroxylase, and α-synuclein immunoreactivity. Neuronal counts were performed stereologically, whereas α-synuclein burden in oligodendrocytes and neurons was quantified using object detection density (area/mm2).. All MSA cases had orthostatic hypotension; 5 had laryngeal stridor. There was marked neuronal loss in the rostral ventrolateral medulla and medullary raphe in all cases. Most severely affected were tyrosine hydroxylase ventrolateral medulla (C1) neurons (83% reduction), followed by tryptophan hydroxylase neurons in the ventrolateral medulla (70%), raphe obscurus (56%), pallidus (57%), and magnus (47%). α-Synuclein accumulation occurred predominantly as glial cytoplasmic inclusions with rare α-synuclein accumulation occurring within the remaining neurons. Density of α-synuclein did not correlate with neuronal loss in any of the areas analyzed, and there was no correlation between α-synuclein density and disease duration for any regions of interest.. These findings indicate that in MSA adrenergic neurons are more susceptible than serotonergic neurons in the medulla. Further, loss of medullary monoaminergic neurons may progress independently from α-synuclein accumulation in MSA. © 2016 International Parkinson and Movement Disorder Society.

Topics: Adrenergic Neurons; Aged; alpha-Synuclein; Female; Humans; Hypotension, Orthostatic; Laryngeal Diseases; Male; Medulla Oblongata; Middle Aged; Multiple System Atrophy; Raphe Nuclei; Respiratory Sounds; Serotonergic Neurons

Multiple system atrophy (MSA) is a distinct member of a group of neurodegenerative diseases known as α-synucleinopathies, which are characterized by the presence of aggregated α-synuclein in the brain. MSA is unique in that the principal site for α-synuclein deposition is in the oligodendrocytes rather than neurons. The cause of MSA is unknown, and the pathogenesis of MSA is still largely speculative. Brain transcriptome perturbations during the onset and progression of MSA are mostly unknown. Using RNA sequencing, we performed a comparative transcriptome profiling analysis of the grey matter (GM) and white matter (WM) of the frontal cortex of MSA and control brains. The transcriptome sequencing revealed increased expression of the alpha and beta haemoglobin genes in MSA WM, decreased expression of the transthyretin (TTR) gene in MSA GM and numerous region-specific long intervening non-coding RNAs (lincRNAs). In contrast, we observed only moderate changes in the expression patterns of the α-synuclein (SNCA) gene, which confirmed previous observations by other research groups. Our study suggests that at the transcriptional level, MSA pathology may be related to increased iron levels in WM and perturbations of the non-coding fraction of the transcriptome.

Topics: Aged; Aged, 80 and over; alpha-Synuclein; Frontal Lobe; Gene Expression Profiling; Gray Matter; Humans; Male; Middle Aged; Multiple System Atrophy; White Matter

Multiple system atrophy (MSA) is a progressive neurodegenerative disorder characterized by poorly levodopa-responsive parkinsonism, cerebellar ataxia, and autonomic dysfunction. Pathogenic mechanisms remain obscure, but the neuropathological hallmark is the presence of α-synuclein-positive glial cytoplasmic inclusions. Previous studies suggested that a single nucleotide polymorphism (SNP), rs11931074, in the α-synuclein gene, SNCA, had highly significant association with an increased risk of the development of MSA in the Caucasian subjects. In contrast, a Korean study failed to identify an association with disease risk.. To study the effect of rs11931074 on MSA risk in a Chinese population, we conducted a case-control study and genotyped SNP rs11931074 by Sanger sequencing in 96 Chinese patients with MSA and 120 healthy controls. Moreover, we performed a meta-analysis on the topic.. There was no statistical difference in genotypes or allele frequencies of SNP rs11931074 between MSA and control groups in our cohort. The results of meta-analysis showed that the risk allele T of rs11931074 was associated with MSA (pooled odds ratio = 1.26, 95% confidence interval = 1.07-1.49, P = 0.006).. Despite a positive result of the meta-analysis, the significant difference in frequency of allele T of rs11931074 between Asian and Caucasian subjects indicates that population heterogeneity at rs11931074 may exist.

Topics: alpha-Synuclein; Asian People; Case-Control Studies; Female; Gene Frequency; Genetic Predisposition to Disease; Genotype; Humans; Male; Meta-Analysis as Topic; Multiple System Atrophy; Polymorphism, Single Nucleotide

Multiple system atrophy (MSA) exhibits widespread astrogliosis together with α-synuclein (α-syn) glial cytoplasmic inclusions (GCIs) in mature oligodendrocytes. We quantified astrocyte activation by morphometric analysis of MSA cases, and investigated the correlation to GCI proximity. Using Imaris software, we obtained "skinned" three-dimensional models of GFAP-positive astrocytes in MSA and control tissue (n=75) from confocal z-stacks and measured the astrocyte process length and thickness and radial distance to the GCI. Astrocytes proximal to GCI-containing oligodendrocytes (r<25μm) had significantly (p, 0.05) longer and thicker processes characteristic of activation than distal astrocytes (r>25μm), with a reciprocal linear correlation (m, 90μm(2)) between mean process length and radial distance to the nearest GCI (R(2), 0.7). In primary cell culture studies, α-syn addition caused ERK-dependent activation of rat astrocytes and perinuclear α-syn inclusions in mature (MOSP-positive) rat oligodendrocytes. Activated astrocytes were also observed in close proximity to α-syn deposits in a unilateral rotenone-lesion mouse model. Moreover, unilateral injection of MSA tissue-derived α-syn into the mouse medial forebrain bundle resulted in widespread neuroinflammation in the α-syn-injected, but not sham-injected hemisphere. Taken together, our data suggests that the action of localized concentrations of α-syn may underlie both astrocyte and oligodendrocyte MSA pathological features.

Topics: Aged; alpha-Synuclein; Animals; Astrocytes; Cells, Cultured; Humans; Inclusion Bodies; Mice; Mice, Inbred C57BL; Multiple System Atrophy; Rats; Rats, Wistar

We used double immunocytochemistry for α-synuclein and markers of sympathoexcitatory neurons, oligodendrocytes, iron metabolism, and autophagy to study putative neuropathological interactions in multiple system atrophy. We focused in the rostral ventrolateral medulla as a prototype vulnerable region. We found that loss of C1 neurons and oligodendrocytes related to glial cytoplasmic inclusion accumulation, downregulation of iron transport, and upregulation of autophagy and ferritin expression in these area.

Topics: Aged; alpha-Synuclein; Animals; Apoptosis Regulatory Proteins; Beclin-1; Brain Stem; Case-Control Studies; Cation Transport Proteins; Disease Models, Animal; Humans; Male; Membrane Proteins; Mice; Middle Aged; Multiple System Atrophy; Neuroglia; Oligodendroglia

Glial cytoplasmic inclusions containing α-synuclein are the pathological hallmark of multiple system atrophy (MSA). Minimal change (MC-MSA) is an unusual MSA subtype with neuronal loss largely restricted to the substantia nigra and locus coeruleus.. Immunohistochemistry on selected brain regions and semiquantitative assessment were performed on six MC-MSA and eight MSA control cases.. More neuronal cytoplasmic inclusions were seen in the caudate and substantia nigra in MC-MSA than in MSA controls (P = 0.002), without any statistical difference in glial cytoplasmic inclusion load in any region. Severe glial cytoplasmic inclusion load was found in the ventrolateral medulla (P = 1.0) and nucleus raphe obscurus (P = 0.4) in both groups. When compared with MSA controls, the three MC-MSA cases who had died of sudden unexpected death had an earlier age of onset (mean: 38 vs. 57.6 y, P = 0.02), a numerically shorter disease duration (mean: 5.3 vs. 8 y, P = 0.2) and a more rapid clinical progression with most of the clinical milestones reached within 3 y of presentation, suggesting an aggressive variant of MSA. Another three MC-MSA cases, who had died of unrelated concurrent diseases, had an age of onset (mean: 57.7 y) and temporal course similar to controls, had less severe neuronal loss and gliosis in the medial and dorsolateral substantia nigra subregions (P < 0.05) than in MSA controls, and could be considered as a unique group with interrupted pathological progression. Significant respiratory dysfunction and early orthostatic hypotension were observed in all MC-MSA cases.. Our findings could suggest that α-synuclein-associated oligodendroglial pathology may lead to neuronal dysfunction sufficient to cause clinical symptoms before overt neuronal loss in MSA. © 2015 International Parkinson and Movement Disorder Society.

Topics: Adult; Age of Onset; Aged; Aged, 80 and over; alpha-Synuclein; Brain; Humans; Inclusion Bodies; Male; Middle Aged; Multiple System Atrophy; Tissue Banks

Multiple system atrophy (MSA) is a neurodegenerative disease characterized by parkinsonism, ataxia and dysautonomia. Histopathologically, the hallmark of MSA is the abnormal accumulation of alpha-synuclein (α-syn) within oligodendroglial cells, leading to neuroinflammation, demyelination and neuronal death. Currently, there is no disease-modifying treatment for MSA. In this sense, we have previously shown that next-generation active vaccination technology with short peptides, AFFITOPEs®, was effective in two transgenic models of synucleinopathies at reducing behavioral deficits, α-syn accumulation and inflammation.. In this manuscript, we used the most effective AFFITOPE® (AFF 1) for immunizing MBP-α-syn transgenic mice, a model of MSA that expresses α-syn in oligodendrocytes. Vaccination with AFF 1 resulted in the production of specific anti-α-syn antibodies that crossed into the central nervous system and recognized α-syn aggregates within glial cells. Active vaccination with AFF 1 resulted in decreased accumulation of α-syn, reduced demyelination in neocortex, striatum and corpus callosum, and reduced neurodegeneration. Clearance of α-syn involved activation of microglia and reduced spreading of α-syn to astroglial cells.. This study further validates the efficacy of vaccination with AFFITOPEs® for ameliorating the neurodegenerative pathology in synucleinopathies.

Topics: alpha-Synuclein; Animals; Astrocytes; Demyelinating Diseases; Disease Models, Animal; Mice, Transgenic; Microglia; Multiple System Atrophy; Neurons; Oligodendroglia; Parkinsonian Disorders; Vaccination

Urinary urgency and frequency are common in α-synucleinopathies such as Parkinson disease, Lewy body dementia, and multiple system atrophy. These symptoms cannot be managed with dopamine therapy, and their underlying pathophysiology is unclear. We show that in individuals with Parkinson disease, Lewy body dementia, or multiple system atrophy, α-synuclein pathology accumulates in the lateral collateral pathway, a region of the sacral spinal dorsal horn important for the relay of pelvic visceral afferents. Deposition of α-synuclein in this region may contribute to impaired micturition and/or constipation in Parkinson disease and other α-synucleinopathies.

Topics: Aged; Aged, 80 and over; alpha-Synuclein; Alzheimer Disease; Brain; Female; Humans; Immunohistochemistry; Lewy Body Disease; Lumbar Vertebrae; Male; Middle Aged; Multiple System Atrophy; Parkinson Disease; Sacrum; Spinal Cord; Spinal Cord Dorsal Horn; Thoracic Vertebrae; Urinary Incontinence; Visceral Afferents

Multiple system atrophy (MSA) is a sporadic neurodegenerative disease clinically characterized by cerebellar signs, parkinsonism, and autonomic dysfunction. Pathologically, MSA is an α-synucleinopathy affecting striatonigral and olivopontocerebellar systems, while neocortical and limbic involvement is usually minimal. In this study, we describe four patients with atypical MSA with clinical features consistent with frontotemporal dementia (FTD), including two with corticobasal syndrome, one with progressive non-fluent aphasia, and one with behavioral variant FTD. None had autonomic dysfunction. All had frontotemporal atrophy and severe limbic α-synuclein neuronal pathology. The neuronal inclusions were heterogeneous, but included Pick body-like inclusions. The latter were strongly associated with neuronal loss in the hippocampus and amygdala. Unlike typical Pick bodies, the neuronal inclusions were positive on Gallyas silver stain and negative on tau immunohistochemistry. In comparison to 34 typical MSA cases, atypical MSA had significantly more neuronal inclusions in anteromedial temporal lobe and limbic structures. While uncommon, our findings suggest that MSA may present clinically and pathologically as a frontotemporal lobar degeneration (FTLD). We suggest that this may represent a novel subtype of FTLD associated with α-synuclein (FTLD-synuclein).

Topics: Aged; Aged, 80 and over; alpha-Synuclein; Brain; Female; Frontotemporal Lobar Degeneration; Humans; Multiple System Atrophy; tau Proteins

Multiple system atrophy is a sporadic alpha-synucleinopathy that typically affects patients in their sixth decade of life and beyond. The defining clinical features of the disease include progressive autonomic failure, parkinsonism, and cerebellar ataxia leading to significant disability. Pathologically, multiple system atrophy is characterized by glial cytoplasmic inclusions containing filamentous alpha-synuclein. Neuronal inclusions also have been reported but remain less well defined. This study aimed to further define the spectrum of neuronal pathology in 35 patients with multiple system atrophy (20 male, 15 female; mean age at death 64.7 years; median disease duration 6.5 years, range 2.2 to 15.6 years). The morphologic type, topography, and frequencies of neuronal inclusions, including globular cytoplasmic (Lewy body-like) neuronal inclusions, were determined across a wide spectrum of brain regions. A correlation matrix of pathologic severity also was calculated between distinct anatomic regions of involvement (striatum, substantia nigra, olivary and pontine nuclei, hippocampus, forebrain and thalamus, anterior cingulate and neocortex, and white matter of cerebrum, cerebellum, and corpus callosum). The major finding was the identification of widespread neuronal inclusions in the majority of patients, not only in typical disease-associated regions (striatum, substantia nigra), but also within anterior cingulate cortex, amygdala, entorhinal cortex, basal forebrain and hypothalamus. Neuronal inclusion pathology appeared to follow a hierarchy of region-specific susceptibility, independent of the clinical phenotype, and the severity of pathology was duration-dependent. Neuronal inclusions also were identified in regions not previously implicated in the disease, such as within cerebellar roof nuclei. Lewy body-like inclusions in multiple system atrophy followed the stepwise anatomic progression of Lewy body-spectrum disease inclusion pathology in 25.7% of patients with multiple system atrophy, including a patient with visual hallucinations. Further, the presence of Lewy body-like inclusions in neocortex, but not hippocampal alpha-synuclein pathology, was associated with cognitive impairment (P = 0.002). However, several cases had the presence of isolated Lewy body-like inclusions at atypical sites (e.g. thalamus, deep cerebellar nuclei) that are not typical for Lewy body-spectrum disease. Finally, interregional correlations (rho ≥ 0.6) in pathologic glial

Topics: Aged; Aged, 80 and over; alpha-Synuclein; Brain; Female; Humans; Inclusion Bodies; Lewy Body Disease; Male; Middle Aged; Multiple System Atrophy; Neuroglia; Neurons

The histological hallmark of multiple system atrophy (MSA) is the presence of filamentous aggregations of phosphorylated α-synuclein in oligodendrocytes, referred to as glial cytoplasmic inclusions (GCIs). Although GCIs can occur widely in the central nervous system, accumulation of phosphorylated α-synuclein in Schwann cells has not been reported in MSA. We immunohistochemically examined the cranial and spinal nerves, peripheral ganglia and visceral autonomic nervous system of patients with MSA (n = 14) and control subjects (n = 20).. In MSA, accumulation of phosphorylated α-synuclein was found in the cytoplasm of Schwann cells. These Schwann cell cytoplasmic inclusions (SCCIs) were also immunopositive for ubiquitin and p62. SCCIs were found in 12 of 14 patients with MSA (85.7 %). They were most frequent in the anterior nerve of the sacral cord and, to a lesser extent, in the cranial nerves (oculomotor, glossopharyngeal-vagus and hypoglossal nerves), and spinal and sympathetic ganglia. SCCIs were rarely found in the visceral organs. Immunoelectron microscopy demonstrated that the SCCIs consisted of abnormal filaments, 15-20 nm in diameter. No such inclusions were found in controls.. The present findings indicate that Schwann cells are also involved in the disease process of MSA.

Topics: Adaptor Proteins, Signal Transducing; Aged; alpha-Synuclein; Autonomic Nervous System; Cranial Nerves; Cytoskeleton; Female; Ganglia; Humans; Immunohistochemistry; Inclusion Bodies; Male; Microscopy, Immunoelectron; Middle Aged; Multiple System Atrophy; Phosphorylation; Schwann Cells; Sequestosome-1 Protein; Spinal Nerves; Ubiquitin

Deposition of phosphorylated SNCA (also known as α-synuclein) in cutaneous nerve fibres has been shown pre- and post-mortem in Parkinson's disease. Thus far, no pre-mortem studies investigating the presence of phosphorylated SNCA in skin sympathetic nerve fibres of multiple system atrophy, another synucleinopathy, have been conducted. In this in vivo study, skin from the ventral forearm of 10 patients with multiple system atrophy and 10 with Parkinson's disease, together with six control subjects with essential tremor, were examined by immunohistochemistry. Phosphorylated SNCA deposits in skin sympathetic nerve fibres and dermal nerve fibre density were assessed. All patients with Parkinson's disease expressed phosphorylated SNCA in sympathetic skin nerve fibres, correlating with an age-independent denervation of autonomic skin elements. In contrast, no phosphorylated SNCA was found in autonomic skin nerve fibres of patients with multiple system atrophy and essential tremor control subjects. These findings support that phosphorylated SNCA deposition is causative for nerve fibre degeneration in Parkinson's disease. Moreover, pre-mortem investigation of phosphorylated SNCA in cutaneous nerve fibres may prove a relevant and easily conductible diagnostic procedure to differentiate Parkinson's disease from multiple system atrophy.

Topics: Aged; Aged, 80 and over; alpha-Synuclein; Brain; Female; Humans; Male; Middle Aged; Multiple System Atrophy; Nerve Degeneration; Nerve Fibers; Parkinson Disease; Phosphorylation; Skin

Topics: alpha-Synuclein; Animals; Female; Humans; Lewy Body Disease; Multiple System Atrophy; Parkinson Disease

Misfolded protein aggregates represent a continuum with overlapping features in neurodegenerative diseases, but differences in protein components and affected brain regions. The molecular hallmark of synucleinopathies such as Parkinson's disease, dementia with Lewy bodies and multiple system atrophy are megadalton α-synuclein-rich deposits suggestive of one molecular event causing distinct disease phenotypes. Glial α-synuclein (α-SYN) filamentous deposits are prominent in multiple system atrophy and neuronal α-SYN inclusions are found in Parkinson's disease and dementia with Lewy bodies. The discovery of α-SYN assemblies with different structural characteristics or 'strains' has led to the hypothesis that strains could account for the different clinico-pathological traits within synucleinopathies. In this study we show that α-SYN strain conformation and seeding propensity lead to distinct histopathological and behavioural phenotypes. We assess the properties of structurally well-defined α-SYN assemblies (oligomers, ribbons and fibrils) after injection in rat brain. We prove that α-SYN strains amplify in vivo. Fibrils seem to be the major toxic strain, resulting in progressive motor impairment and cell death, whereas ribbons cause a distinct histopathological phenotype displaying Parkinson's disease and multiple system atrophy traits. Additionally, we show that α-SYN assemblies cross the blood-brain barrier and distribute to the central nervous system after intravenous injection. Our results demonstrate that distinct α-SYN strains display differential seeding capacities, inducing strain-specific pathology and neurotoxic phenotypes.

Topics: alpha-Synuclein; Animals; Blood-Brain Barrier; Brain; Female; Humans; Lewy Body Disease; Multiple System Atrophy; Parkinson Disease; Phenotype; Rats; Rats, Wistar; Substantia Nigra; Synapses

Topics: alpha-Synuclein; Brain; Female; Frontotemporal Lobar Degeneration; Humans; Multiple System Atrophy

Topics: alpha-Synuclein; Animals; Female; Humans; Lewy Body Disease; Multiple System Atrophy; Parkinson Disease

MSA is characterized by deposition of alpha-synuclein (α-Syn) in oligodendrocytes and central nervous system (CNS) neurons. After recently detecting phospho-α-Syn (p-α-Syn) in dermal nerve fibers of patients with Parkinson's disease (PD), we assessed skin biopsies from patients with MSA to evaluate its potential role as a biomarker.. Skin biopsies of patients with MSA (n = 12), idiopathic PD (n = 30), tauopathies (n = 15), and normal controls (n = 39) were analyzed. P-α-Syn within dermal nerves was detected by immunofluorescence staining.. p-α-Syn was found in 67% of patients with MSA and Parkinson's disease, but not in patients with tauopathy or controls when analyzing 15 consecutive sections. Sensitivity could be increased to 75% and 73%, respectively, by analyzing serial sections. In contrast to PD, where p-α-Syn clustered in autonomic fibers, deposits were mainly found in unmyelinated somatosensory fibers in MSA.. α-Syn pathology in MSA is not restricted to the CNS, and skin biopsy may be useful for the premortem study of p-α-Syn.

Topics: Aged; alpha-Synuclein; Biopsy; Female; Humans; Male; Middle Aged; Multiple System Atrophy; Nerve Fibers; Parkinson Disease; Skin; Ubiquitin Thiolesterase

Multiple system atrophy (MSA) is a rapidly progressive neurodegenerative disease. Post-mortem hallmarks of MSA neuropathology include oligodendroglial α-synuclein (αSYN) inclusions, striatonigral degeneration, olivopontocerebellar atrophy, and increased microglial activation that accompanies the wide spread neurodegeneration. Recently, we demonstrated upregulation of myeloperoxidase (MPO) in activated microglia and provided evidence for the role of microglial MPO in the mediation of MSA-like neurodegeneration (Stefanova et al. Neurotox Res 21:393-404, 2015). The aim of the current study was to assess the therapeutic potency of MPO inhibition (MPOi) in a model of advanced MSA. We replicated the advanced pathology of MSA by intoxicating transgenic PLP-α-synuclein transgenic mice with 3-nitropropionic acid (3NP). After onset of the full-blown pathology, MSA mice received either MPOi or vehicle over 3 weeks. Motor phenotype and neuropathology were analyzed to assess the therapeutic efficacy of MPOi compared to vehicle treatment in MSA mice. MPOi therapy initiated after the onset of severe MSA-like neuropathology in mice failed to attenuate motor impairments and neuronal loss within the striatum, substantia nigra pars compacta, inferior olives, pontine nuclei, and cerebellar cortex. However, we observed a significant reduction of microglial activation in degenerating brain areas. Further, nitrated αSYN accumulation was reduced in the striatonigral region. In summary, delayed-start MPOi treatment reduced microglial activation and levels of nitrated αSYN in a mouse model of advanced MSA. These effects failed to impact on motor impairments and neuronal loss in contrast to previously reported disease modifying efficacy of early-start therapy with MPOi in MSA.

Topics: alpha-Synuclein; Animals; Brain; Disease Models, Animal; Enzyme Inhibitors; Humans; Male; Mice, Transgenic; Microglia; Motor Activity; Multiple System Atrophy; Myelin Proteolipid Protein; Neurons; Neuroprotective Agents; Nitro Compounds; Peroxidase; Propionates; Pyrimidinones; Pyrroles; Severity of Illness Index; Treatment Outcome

Topics: alpha-Synuclein; Brain; Female; Humans; Male; Multiple System Atrophy; Nerve Fibers; Parkinson Disease; Skin

The polymorphisms of α-synuclein (SNCA), rs3775444, rs3822086 and rs11931074 that are strongly associated with Parkinson's disease (PD) in Caucasian populations, were examined in this study to elucidate the role of polymorphisms in different ethnic backgrounds. The possible associations of these three polymorphisms were also investigated in PD, amyotrophic lateral sclerosis (ALS), and multiple system atrophy (MSA) in a Chinese population based on the overlapping of clinical manifestations and pathological characteristics of these three neurodegenerative diseases.. A total of 1276 PD, 885 sporadic ALS (SALS), 364 MSA patients, and 846 healthy controls (HCs) were included. All subjects were genotyped for the three polymorphisms using Sequenom iPLEX Assay technology.. Significant differences in the genotype distributions (p = 5.99E-06 and p = 4.98E-06, respectively) and the minor allele frequency (MAF) (p = 2.16E-06 and p = 2.15E-06, respectively) of SNCA rs3822086 (C) and rs11931074 (G) were observed between PD and HCs. However, no differences were found in the genotype distributions and MAF of SNCA rs3775444 (T) between PD and HCs. Haplotype that incorporated the three SNPs further strengthened the association with PD (best haplotype, p = 9.62E-005). No significant differences in the genotype distributions and MAF of the SNPs were found between SALS and HCs, MSA and HCs, and subgroups of PD and SALS. However, the MAF of SNCA rs3775444 (T) was significantly higher in MSA patients with frontal lobe dysfunction than MSA patients without dysfunction (p = 0.0002, OR 2.53, 95%CI: 1.55-4.15).. Our results suggest that the rs3822086 (C) allele and rs11931074 (G) allele in SNCA decrease the risk for PD, and SNCA rs11931074 may affect frontal lobe dysfunction of MSA in the Chinese population. However, these SNCA polymorphisms are not likely a common cause of SALS or MSA.

Topics: Aged; Alleles; alpha-Synuclein; Amyotrophic Lateral Sclerosis; Anxiety; Case-Control Studies; China; Depression; Female; Frontal Lobe; Gene Frequency; Genetic Predisposition to Disease; Genetic Variation; Genotype; Humans; Male; Middle Aged; Multiple System Atrophy; Parkinson Disease; Polymorphism, Single Nucleotide

α-Synuclein (α-syn)-containing glial cytoplasmic inclusions originating in oligodendrocytes are characteristically observed in multiple system atrophy. The mechanisms of glial cytoplasmic inclusion formation remain rather elusive. α-Syn over-expression, uptake from the environment, oxidative stress or impairment of the proteolytic degradation systems have been discussed. Here, we investigated whether in oligodendrocytes autophagy plays a major role in the degradation and aggregation of endogenously expressed α-syn and of α-syn taken up from the extracellular environment. Furthermore, we studied whether in cells with impaired mitochondria the accumulation and aggregation of exogenously added α-syn is promoted. Using primary cultures of rat brain oligodendrocytes and an oligodendroglial cell line, genetically engineered to express green fluorescent protein-microtubule-associated light chain 3 with or without α-syn to monitor the autophagic flux, we demonstrate that both exogenously applied α-syn and α-syn stably expressed endogenously are effectively degraded by autophagy and do not affect the autophagic flux per se. Mitochondrial impairment with the protonophore carbonyl cyanide 3-chlorophenylhydrazone or 3-nitropropionic acid disturbs the autophagic pathway and leads to the accumulation of exogenously applied α-syn and enhances its propensity to form aggregates intracellularly. Thus, mitochondrial dysfunction and oxidative stress, which occur over time and are significant pathological features in synucleinopathies, have an impact on the autophagic pathway and participate in pathogenesis. Glial cytoplasmic inclusions are characteristically observed in multiple system atrophy, their occurrence might be related to failure in protein degradation systems. Here, we show that in oligodendrocytes autophagy is the major route of α-synuclein degradation which is either endogenously expressed or added exogenously (1, 2). Mitochondrial impairment (3) disturbs the autophagic flux and leads to the accumulation of exogenously applied α-synuclein, and enhances its propensity to form aggregates intracellulary (4).

Topics: alpha-Synuclein; Animals; Autophagy; Cells, Cultured; Cytoplasm; Mitochondria; Multiple System Atrophy; Nerve Tissue Proteins; Nitro Compounds; Oligodendroglia; Oxidative Stress; Propionates; Rats

MSA is a sporadic progressive neurodegenerative disorder characterized by a variable combination of parkinsonism, cerebellar ataxia, and autonomic dysfunction. The pathological hallmark of MSA is the accumulation of alpha-synuclein aggregates in the cytoplasm of oligodendrocytes along with neuronal loss and neuroinflammation, as well as blood-brain barrier dysfunction and myelin deterioration. Matrix metalloproteinases are zinc-dependent endopeptidases involved in the remodeling of the extracellular matrix, demyelination, and blood-brain barrier permeability. Several lines of evidence indicate a role for these enzymes in various pathological processes, including stroke, multiple sclerosis, Parkinson's, and Alzheimer's disease.. This study aimed to assess potential alterations of matrix metalloproteinase-1, -2, -3, and -9 expression or activity in MSA postmortem brain tissue.. Gelatin zymography revealed increased matrix metalloproteinase-2 activity in the putamen, but not in the frontal cortex, of MSA patients relative to controls. Immunohistochemistry revealed increased number of glial cells positive for matrix metalloproteinase-1, -2, and -3 in the putamen and frontal cortex of MSA patients. Double immunofluorescence revealed that matrix metalloproteinase-2 and -3 were expressed in astrocytes and microglia. Only matrix metalloproteinase-2 colocalized with alpha-synuclein in oligodendroglial cytoplasmic inclusions.. These results demonstrate widespread alterations of matrix metalloproteinase expression in MSA and a pattern of increased matrix metalloproteinase-2 expression and activity affecting preferentially a brain region severely affected (putamen) over a relatively spared region (frontal cortex). Elevated matrix metalloproteinase expression may thus contribute to the disease process in MSA by promoting blood-brain barrier dysfunction and/or myelin degradation.

Topics: Adult; Aged; alpha-Synuclein; Brain; Calcium-Binding Proteins; Densitometry; DNA-Binding Proteins; Female; Glial Fibrillary Acidic Protein; Humans; Male; Matrix Metalloproteinases; Microfilament Proteins; Middle Aged; Multiple System Atrophy; Neuroglia; Neurons; Postmortem Changes; Young Adult

We and others have described the neurodegenerative disorder caused by G51D SNCA mutation which shares characteristics of Parkinson's disease (PD) and multiple system atrophy (MSA). The objective of this investigation was to extend the description of the clinical and neuropathological hallmarks of G51D mutant SNCA-associated disease by the study of two additional cases from a further G51D SNCA kindred and to compare the features of this group with a SNCA duplication case and a H50Q SNCA mutation case.. All three G51D patients were clinically characterised by parkinsonism, dementia, visual hallucinations, autonomic dysfunction and pyramidal signs with variable age at disease onset and levodopa response. The H50Q SNCA mutation case had a clinical picture that mimicked late-onset idiopathic PD with a good and sustained levodopa response. The SNCA duplication case presented with a clinical phenotype of frontotemporal dementia with marked behavioural changes, pyramidal signs, postural hypotension and transiently levodopa responsive parkinsonism. Detailed post-mortem neuropathological analysis was performed in all cases. All three G51D cases had abundant α-synuclein pathology with characteristics of both PD and MSA. These included widespread cortical and subcortical neuronal α-synuclein inclusions together with small numbers of inclusions resembling glial cytoplasmic inclusions (GCIs) in oligodendrocytes. In contrast the H50Q and SNCA duplication cases, had α-synuclein pathology resembling idiopathic PD without GCIs. Phosphorylated α-synuclein was present in all inclusions types in G51D cases but was more restricted in SNCA duplication and H50Q mutation. Inclusions were also immunoreactive for the 5G4 antibody indicating their highly aggregated and likely fibrillar state.. Our characterisation of the clinical and neuropathological features of the present small series of G51D SNCA mutation cases should aid the recognition of this clinico-pathological entity. The neuropathological features of these cases consistently share characteristics of PD and MSA and are distinct from PD patients carrying the H50Q or SNCA duplication.

Topics: Age of Onset; Aged; alpha-Synuclein; Amino Acid Substitution; Antiparkinson Agents; Brain; Codon; Dementia; Disease Progression; Female; Gene Duplication; Humans; Inclusion Bodies; Male; Middle Aged; Multiple System Atrophy; Mutation, Missense; Parkinson Disease; Pedigree; Point Mutation; Protein Conformation; Protein Processing, Post-Translational; Symptom Assessment; Young Adult

Prions are proteins that adopt alternative conformations that become self-propagating; the PrP(Sc) prion causes the rare human disorder Creutzfeldt-Jakob disease (CJD). We report here that multiple system atrophy (MSA) is caused by a different human prion composed of the α-synuclein protein. MSA is a slowly evolving disorder characterized by progressive loss of autonomic nervous system function and often signs of parkinsonism; the neuropathological hallmark of MSA is glial cytoplasmic inclusions consisting of filaments of α-synuclein. To determine whether human α-synuclein forms prions, we examined 14 human brain homogenates for transmission to cultured human embryonic kidney (HEK) cells expressing full-length, mutant human α-synuclein fused to yellow fluorescent protein (α-syn140*A53T-YFP) and TgM83(+/-) mice expressing α-synuclein (A53T). The TgM83(+/-) mice that were hemizygous for the mutant transgene did not develop spontaneous illness; in contrast, the TgM83(+/+) mice that were homozygous developed neurological dysfunction. Brain extracts from 14 MSA cases all transmitted neurodegeneration to TgM83(+/-) mice after incubation periods of ∼120 d, which was accompanied by deposition of α-synuclein within neuronal cell bodies and axons. All of the MSA extracts also induced aggregation of α-syn*A53T-YFP in cultured cells, whereas none of six Parkinson's disease (PD) extracts or a control sample did so. Our findings argue that MSA is caused by a unique strain of α-synuclein prions, which is different from the putative prions causing PD and from those causing spontaneous neurodegeneration in TgM83(+/+) mice. Remarkably, α-synuclein is the first new human prion to be identified, to our knowledge, since the discovery a half century ago that CJD was transmissible.

Topics: Aged; alpha-Synuclein; Animals; Brain; Exons; Female; HEK293 Cells; Humans; Immunohistochemistry; Male; Mice; Mice, Transgenic; Microscopy, Fluorescence; Middle Aged; Multiple System Atrophy; Neurodegenerative Diseases; Parkinsonian Disorders; Phosphorylation; Polymorphism, Single Nucleotide; Prions; Ubiquinone

Topics: alpha-Synuclein; Animals; Female; Humans; Male; Multiple System Atrophy; Parkinsonian Disorders; Prions

To assess the importance of MAPT variant p.A152T in the risk of synucleinopathies.. In this case-control study, we screened a large global series of patients and controls, and assessed associations between p.A152T and disease risk. We included 3,229 patients with clinical Parkinson disease (PD), 442 with clinical dementia with Lewy bodies (DLB), 181 with multiple system atrophy (MSA), 832 with pathologically confirmed Lewy body disease (LBD), and 2,456 healthy controls.. The minor allele frequencies (MAF) in clinical PD cases (0.28%) and in controls (0.2%) were not found to be significantly different (odds ratio [OR] 1.37, 95% confidence interval [CI] 0.63-2.98, p = 0.42). However, a significant association was observed with clinical DLB (MAF 0.68%, OR 5.76, 95% CI 1.62-20.51, p = 0.007) and LBD (MAF 0.42%, OR 3.55, 95% CI 1.04-12.17, p = 0.04). Additionally, p.A152T was more common in patients with MSA compared to controls (MAF 0.55%, OR 4.68, 95% CI 0.85-25.72, p = 0.08) but this was not statistically significant and therefore should be interpreted with caution.. Overall, our findings suggest that MAPT p.A152T is a rare low penetrance variant likely associated with DLB that may be influenced by coexisting LBD and AD pathology. Given the rare nature of the variant, further studies with greater sample size are warranted and will help to fully explain the role of p.A152T in the pathogenesis of the synucleinopathies.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; alpha-Synuclein; Case-Control Studies; Female; Genetic Predisposition to Disease; Genetic Variation; Humans; Lewy Body Disease; Male; Middle Aged; Multiple System Atrophy; Parkinson Disease; tau Proteins; Young Adult

Multiple system atrophy (MSA) is a progressive, neurodegenerative disease characterized by parkinsonism, resistance to dopamine therapy, ataxia, autonomic dysfunction, and pathological accumulation of α-synuclein (α-syn) in oligodendrocytes. Neurosin (kallikrein-6) is a serine protease capable of cleaving α-syn in the CNS, and we have previously shown that lentiviral (LV) vector delivery of neurosin into the brain of a mouse model of dementia with Lewy body/ Parkinson's disease reduces the accumulation of α-syn and improves neuronal synaptic integrity.. In this study, we investigated the ability of a modified, systemically delivered neurosin to reduce the levels of α-syn in oligodendrocytes and reduce the cell-to-cell spread of α-syn to glial cells in a mouse model of MSA (MBP-α-syn). We engineered a viral vector that expresses a neurosin genetically modified for increased half-life (R80Q mutation) that also contains a brain-targeting sequence (apoB) for delivery into the CNS. Peripheral administration of the LV-neurosin-apoB to the MBP-α-syn tg model resulted in accumulation of neurosin-apoB in the CNS, reduced accumulation of α-syn in oligodendrocytes and astrocytes, improved myelin sheath formation in the corpus callosum and behavioral improvements.. Thus, the modified, brain-targeted neurosin may warrant further investigation as potential therapy for MSA.

Topics: alpha-Synuclein; Animals; Astrocytes; Behavior, Animal; Cells, Cultured; Disease Models, Animal; Kallikreins; Mice; Multiple System Atrophy; Oligodendroglia; Parkinson Disease

Parkinson disease (PD), multiple system atrophy (MSA), and pure autonomic failure (PAF) involve cytoplasmic deposition of α-synuclein and are considered to be synucleinopathies. Approximately 40% of patients with PD, most patients with MSA, and all patients with PAF have neurogenic orthostatic hypotension (OH). This study compared long-term survival in these synucleinopathies.. In this prospective cohort study, survival data were obtained for 97.6% of 206 referred patients evaluated between 1994 and 2014 (47 PD + OH, 54 PD no OH, 15 cerebellar MSA [MSA-C], 57 parkinsonian MSA [MSA-P], 28 PAF). Individual diagnoses were confirmed by clinical criteria and results of pharmacologic, neurochemical, and neuroimaging tests of sympathetic noradrenergic innervation. The Cox proportional hazard model was used to calculate hazard ratios (HRs) from symptom onset and from time of evaluation to death.. Patients with MSA-C or MSA-P had shorter survival from symptom onset than did patients with PD + OH (age- and sex-adjusted HR = 6.1, 5.6; p < 0.0001 each), PAF (HR = 10.8, 9.9; p < 0.0001 each) or PD no OH (HR = 14.9, 13.6; p < 0.0001 each). Among parkinsonian patients who died, median times from motor onset to death were 7.5 years in MSA-P, 11.6 years in PD + OH, and 15.8 years in PD no OH. Probabilities of survival for 10 years from onset of relevant symptoms were 0.39 in MSA-C, 0.33 in MSA-P, 0.74 in PD + OH, 0.87 in PAF, and 0.93 in PD no OH.. In synucleinopathies, survival depends on the particular disease, with the risk of death greater in MSA-P than in PD + OH and in PD + OH than in PD no OH.

Topics: Aged; alpha-Synuclein; Brain; Cerebellar Diseases; Cohort Studies; Dihydroxyphenylalanine; Female; Fluorine Radioisotopes; Humans; Longitudinal Studies; Male; Middle Aged; Multiple System Atrophy; Parkinson Disease; Parkinsonian Disorders; Proportional Hazards Models; Prospective Studies; Pure Autonomic Failure; Radionuclide Imaging

Multiple system atrophy (MSA) is a fatal, rapidly progressive neurodegenerative disease with (oligodendro-)glial cytoplasmic α-synuclein (α-syn) inclusions (GCIs). Peripheral neuropathies have been reported in up to 40% of MSA patients, the cause remaining unclear. In a transgenic MSA mouse model featuring GCI-like inclusion pathology based on PLP-promoter driven overexpression of human α-syn in oligodendroglia motor and non-motor deficits are associated with MSA-like neurodegeneration. Since α-syn is also expressed in Schwann cells we aimed to investigate whether peripheral nerves are anatomically and functionally affected in the PLP-α-syn MSA mouse model.. To this end, heat/cold as well as mechanical sensitivity tests were performed. Furthermore, in vivo and ex vivo nerve conduction and the G-ratios of the sciatic nerve were analyzed, and thermosensitive ion channel mRNA expression in dorsal root ganglia (DRG) was assessed. The presence of human α-syn in Schwann cells was associated with subtle behavioral impairments. The G-ratio of the sciatic nerve, the conduction velocity of myelinated and unmyelinated primary afferents and the expression of thermosensitive ion channels in the sensory neurons, however, were similar to wildtype mice.. Our results suggest that the PNS appears to be affected by Schwann cell α-syn deposits in the PLP-α-syn MSA mouse model. However, there was no consistent evidence for functional PNS perturbations resulting from such α-syn aggregates suggesting a more central cause of the observed behavioral abnormalities. Nonetheless, our results do not exclude a causal role of α-syn in the pathogenesis of MSA associated peripheral neuropathy.

Topics: alpha-Synuclein; Animals; Behavior, Animal; Cold Temperature; Disease Models, Animal; Fluorescent Antibody Technique; Ganglia, Spinal; Gene Expression Regulation; Hot Temperature; Humans; Male; Mice, Inbred C57BL; Mice, Transgenic; Motor Activity; Multiple System Atrophy; Myelin Proteolipid Protein; Neural Conduction; Phenotype; RNA, Messenger; Schwann Cells; Sciatic Nerve; Time Factors; Transient Receptor Potential Channels; TRPA1 Cation Channel; TRPM Cation Channels

Parkinson's disease (PD) and multiple system atrophy (MSA) are neurodegenerative diseases that are characterized by the intracellular accumulation of alpha-synuclein containing aggregates. Recent increasing evidence suggests that Parkinson's disease and MSA pathology spread throughout the nervous system in a spatiotemporal fashion, possibly by prion-like propagation of alpha-synuclein positive aggregates between synaptically connected areas. Concurrently, intracerebral injection of pathological alpha-synuclein into transgenic mice overexpressing human wild-type alpha-synuclein, or human alpha-synuclein with the familial A53T mutation, or into wild-type mice causes spreading of alpha-synuclein pathology in the CNS. Considering that wild-type mice naturally also express a threonine at codon 53 of alpha-synuclein, it has remained unclear whether human wild-type alpha-synuclein alone, in the absence of endogenously expressed mouse alpha-synuclein, would support a similar propagation of alpha-synuclein pathology in vivo.. Here we show that brain extracts from two patients with MSA and two patients with probable incidental Lewy body disease (iLBD) but not phosphate-buffered saline induce prion-like spreading of pathological alpha-synuclein after intrastriatal injection into mice expressing human wild-type alpha-synuclein. Mice were sacrificed at 3, 6, and 9 months post injection and analyzed neuropathologically and biochemically. Mice injected with brain extracts from patients with MSA or probable iLBD both accumulated intraneuronal inclusion bodies, which stained positive for phosphorylated alpha-synuclein and appeared predominantly within the injected brain hemisphere after 6 months. After 9 months these intraneuronal inclusion bodies had spread to the contralateral hemisphere and more rostral and caudal areas. Biochemical analysis showed that brains of mice injected with brain extracts from patients with MSA and probable iLBD contained hyperphosphorylated alpha-synuclein that also seeded aggregation of recombinant human wild-type alpha-synuclein in a Thioflavin T binding assay.. Our results indicate that human wild-type alpha-synuclein supports the prion-like spreading of alpha-synuclein pathology in the absence of endogenously expressed mouse alpha-synuclein in vivo.

Topics: Adaptor Proteins, Signal Transducing; Age Factors; alpha-Synuclein; Animals; Brain; Female; Gene Expression Regulation; Heat-Shock Proteins; Humans; Lewy Body Disease; Male; Mice; Mice, Transgenic; Multiple System Atrophy; Mutation; Phosphorylation; Sequestosome-1 Protein; Ubiquitin

Multiple system atrophy (MSA) is a fatal adult-onset neurodegenerative disease characterized by α-synuclein (α-syn) positive oligodendroglial cytoplasmic inclusions. The latter are associated with a neuronal multisystem neurodegeneration targeting central autonomic, olivopontocerebellar and striatonigral pathways, however the underlying mechanisms of neuronal cell death are poorly understood. Previous experiments have shown that oligodendroglial α-syn pathology increases the susceptibility to mitochondrial stress and proteasomal dysfunction leading to enhanced MSA-like neurodegeneration. Here we analyzed whether oligodendroglial α-syn overexpression in a transgenic mouse model of MSA synergistically interacts with focal neuronal excitotoxic damage generated by a striatal injection of quinolinic acid (QA) to affect the degree of striatal neuronal loss.. QA injury led to comparable striatal neuronal loss and optical density of astro- and microgliosis in the striatum of transgenic and control mice. Respectively, no differences were identified in drug-induced rotation behavior or open field behavior between the groups.. The failure of oligodendroglial α-syn pathology to exacerbate striatal neuronal loss resulting from QA excitotoxicity contrasts with enhanced striatal neurodegeneration due to oxidative or proteolytic stress, suggesting that enhanced vulnerability to excitotoxicity does not occur in oligodendroglial α-synucleinopathy like MSA.

Topics: alpha-Synuclein; Animals; Cell Death; Corpus Striatum; Disease Models, Animal; Gliosis; Humans; Mice, Transgenic; Multiple System Atrophy; Neurons; Oligodendroglia; Quinolinic Acid

Spatacsin (SPG11) is a major mutated gene in autosomal recessive spastic paraplegia with thin corpus callosum (ARHSP-TCC) and is responsible for juvenile Parkinsonism. To elucidate the role of spatacsin in the pathogenesis of α-synucleinopathies, an immunohistochemical investigation was performed on the brain of patients with Parkinson's disease (PD), dementia with Lewy bodies (DLB) and multiple system atrophy (MSA) using anti-spatacsin antibody. In PD, Lewy bodies (LBs) in the brain stem were positive for spatacsin. These LBs showed intense staining in their peripheral portions and occasionally in the central cores. Lewy neurites were also spatacsin-positive. In DLB, cortical LBs were immunolabeled by spatacsin. In MSA, glial cytoplasmic inclusions (GCI) and a small fraction of neuronal cytoplasmic inclusions (NCI) were positive for spatacsin. The widespread accumulation of spatacsin observed in pathologic α-synuclein-containing inclusions suggests that spatacsin may be involved in the pathogenesis of α-synucleinopathies.

Topics: Aged; Aged, 80 and over; alpha-Synuclein; Autopsy; Brain; Female; Humans; Immunohistochemistry; Inclusion Bodies; Lewy Body Disease; Male; Middle Aged; Multiple System Atrophy; Parkinson Disease; Proteins; Temporal Lobe

Multiple system atrophy, a sporadic neurodegenerative disease, is characterized by the presence of high numbers of glial cytoplasmic inclusions mainly formed by α-synuclein protein, which is encoded by the SNCA gene. To date, however, few studies have investigated the plasma α-synuclein levels in patients with multiple system atrophy. We studied plasma α-synuclein concentrations by using an enzyme-linked immunosorbent assay in 74 patients with multiple system atrophy and 90 healthy controls. The plasma α-synuclein levels were significantly elevated in patients who had multiple system atrophy compared with the control group (P = 0.000). In a subgroup of 48 patients who had probable multiple system atrophy, there was a weakly negative correlation between plasma α-synuclein levels and subscores on Unified Multiple System Atrophy Rating Scale item VI (r(s)  = -0.307; P = 0.034). Plasma α-synuclein levels were elevated in patients with multiple system atrophy, and these levels may be decreased with the development of disease.

Topics: Adult; Aged; alpha-Synuclein; Brain; Enzyme-Linked Immunosorbent Assay; Female; Gene Expression; Humans; Inclusion Bodies; Male; Middle Aged; Multiple System Atrophy

Multiple system atrophy (MSA) is a neurodegenerative disorder characterized by a progressive degeneration of the striatonigral, olivo-ponto-cerebellar, and autonomic systems. Glial cytoplasmic inclusions (GCIs) containing alpha-synuclein represent the hallmark of MSA and are recapitulated in mice expressing alpha-synuclein in oligodendrocytes. To assess if oligodendroglial expression of human wild-type alpha-synuclein in mice (proteolipid promoter, PLP-SYN) could be associated with age-related deficits, PLP-SYN and wild-type mice were assessed for motor function, brain morphometry, striatal levels of dopamine and metabolites, dopaminergic loss, and distribution of GCIs. PLP-SYN displayed age-related impairments on a beam-traversing task. MRI revealed a significantly smaller brain volume in PLP-SYN mice at 12 months, which further decreased at 18 months together with increased volume of ventricles and cortical atrophy. The distribution of GCIs was reminiscent of MSA with a high burden in the basal ganglia. Mild dopaminergic cell loss was associated with decreased dopamine turnover at 18 months. These data indicate that PLP-SYN mice may recapitulate some of the progressive features of MSA and deliver endpoints for the evaluation of therapeutic strategies.

Topics: Age Factors; alpha-Synuclein; Animals; Atrophy; Brain; Cell Death; Cerebral Ventricles; Corpus Striatum; Dopamine; Humans; Magnetic Resonance Imaging; Male; Mice; Mice, Inbred C57BL; Mice, Transgenic; Motor Activity; Movement Disorders; Multiple System Atrophy; Neuroglia; Organ Size

Multiple system atrophy (MSA) is a neurodegenerative disease characterized by the pathological accumulation of alpha-synuclein (α-syn) within oligodendroglial cells. This accumulation is accompanied by neuroinflammation with astrogliosis and microgliosis, that leads to neuronal death and subsequent parkinsonism and dysautonomia. Antidepressants have been explored as neuroprotective agents as they normalize neurotrophic factor levels, increase neurogenesis and reduce neurodegeneration, but their anti-inflammatory properties have not been fully characterized. We analyzed the anti-inflammatory profiles of three different antidepressants (fluoxetine, olanzapine and amitriptyline) in the MBP1-hα-syn transgenic (tg) mouse model of MSA. We observed that antidepressant treatment decreased the number of α-syn-positive cells in the basal ganglia of 11-month-old tg animals. This reduction was accompanied with a similar decrease in the colocalization of α-syn with astrocyte markers in this brain structure. Consistent with these results, antidepressants reduced astrogliosis in the hippocampus and basal ganglia of the MBP1-hα-syn tg mice, and modulated the expression levels of key cytokines that were dysregulated in the tg mouse model, such as IL-1β. In vitro experiments in the astroglial cell line C6 confirmed that antidepressants inhibited NF-κB translocation to the nucleus and reduced IL-1β protein levels. We conclude that the anti-inflammatory properties of antidepressants in the MBP1-hα-syn tg mouse model of MSA might be related to their ability to inhibit α-syn propagation from oligodendrocytes to astroglia and to regulate transcription factors involved in cytokine expression. Our results suggest that antidepressants might be of interest as anti-inflammatory and α-syn-reducing agents for MSA and other α-synucleinopathies.

Topics: alpha-Synuclein; Animals; Antidepressive Agents; Astrocytes; Disease Models, Animal; Inflammation; Mice; Mice, Transgenic; Multiple System Atrophy; Neurons; NF-kappa B; Oligodendroglia

Multiple system atrophy is a progressive, neurodegenerative disease characterized by parkinsonism, ataxia, autonomic dysfunction, and accumulation of α-synuclein in oligodendrocytes. To understand how α-synuclein aggregates impact oligodendroglial homeostasis, we investigated an oligodendroglial cell model of α-synuclein dependent degeneration and identified responses linked to the NF-κB transcription factor stress system. Coexpression of human α-synuclein and the oligodendroglial protein p25α increased the expression of IκBα mRNA and protein early during the degenerative process and this was dependent on both aggregation and Ser129 phosphorylation of α-synuclein. This response was prodegenerative because blocking IκBα expression by siRNA rescued the cells. IκBα is an inhibitor of NF-κB and acts by binding and retaining NF-κB p65 in the cytoplasm. The protection obtained by silencing IκBα was accompanied by a strong increase in nuclear p65 translocation indicating that NF-κB activation protects against α-synuclein aggregate stress. In the cellular model, two different phenotypes were observed; degenerating cells retracting their microtubules and resilient cells tolerating the coexpression of α-synuclein and p25α. The resilient cells displayed a significant higher nuclear translocation of p65 and activation of the NF-κB system relied on stress elicited by aggregated and Ser129 phosphorylated α-synuclein. To validate the relationship between oligodendroglial α-synuclein expression and IκBα, we analyzed two different lines of transgenic mice expressing human α-synuclein under the control of the oligodendrocytic MBP promotor (intermediate-expresser line 1 and high-expresser line 29). IκBα mRNA expression was increased in both lines and immunofluorescence microscopy and in situ hybridization revealed that IκBα mRNA and protein is expressed in oligodendrocytes. IκBα mRNA expression was demonstrated prior to activation of microglia and astrocytes in line 1. Human brain tissue affected by MSA displayed increased expression of IκBα and NF-κB p65 in some oligodendrocytes containing glial cytoplasmic inclusions. Our data suggest that oligodendroglial IκBα expression and NF-κB are activated early in the course of MSA and their balance contributes to the decision of cellular demise. Favoring oligodendroglial NF-κB activation may represent a therapeutic strategy for this devastating disease.

Topics: alpha-Synuclein; Animals; Brain; Cells, Cultured; Gene Expression Regulation; Humans; I-kappa B Proteins; Mice, Transgenic; Multiple System Atrophy; Myelin Basic Protein; Nerve Tissue Proteins; Neuroglia; NF-KappaB Inhibitor alpha; Oligodendroglia; Oligonucleotide Array Sequence Analysis; Phosphotransferases; Protein Transport; Rats; Rats, Wistar; RNA, Small Interfering; Transfection

Topics: alpha-Synuclein; Animals; Disease Transmission, Infectious; Humans; Male; Multiple System Atrophy; Prions

Multiple system atrophy is an intractable neurodegenerative disease caused by α-synuclein (α-syn) accumulation in oligodendrocytes and neurons. With the use of a transgenic mouse model overexpressing human α-syn in oligodendrocytes, we demonstrated that oligodendrocytic α-syn inclusions induce neuronal α-syn accumulation, resulting in progressive neuronal degeneration. The mechanism through which oligodendrocytic α-syn inclusions trigger neuronal α-syn accumulation leading to multiple system atrophy is unknown. In this study, we identified cystatin C, an oligodendrocyte-derived secretory protein that triggers α-syn up-regulation and insoluble α-syn accumulation, in neurons of the mouse central nervous system. Cystatin C was released by mouse oligodendrocytes overexpressing human α-syn, and extracellular cystatin C increased the expression of the endogenous α-syn gene in wild-type mouse neurons. These neurons then accumulate insoluble α-syn and may undergo apoptosis. Cystatin C is a potential pathogenic signal triggering neurodegeneration in multiple system atrophy.

Topics: alpha-Synuclein; Animals; Brain; Cystatin C; Disease Models, Animal; Humans; Mice; Mice, Transgenic; Multiple System Atrophy; Neurons; Oligodendroglia; Up-Regulation

Respiratory dysfunction, including sleep disordered breathing, is characteristic of multiple system atrophy (MSA) and may reflect degeneration of brainstem respiratory nuclei involved in respiratory rhythmogenesis and chemosensitivity, including the pre-Bötzinger complex (preBötC), nucleus raphe pallidus (RPa), and nucleus raphe obscurus (ROb). However, impaired ventilatory responses to hypercapnia have also been reported in dementia with Lewy bodies (DLB), suggesting that these nuclei may also be affected in DLB.. To determine whether there is involvement of the preBötC, RPa, and ROb in DLB.. We applied stereological methods to analyze sections immunostained for neurokinin-1 receptor and tryptophan hydroxylase in neuropathologically confirmed cases of DLB, MSA, and controls.. Reduction of neuronal density occurred in all three nuclei in DLB, as well as in MSA. The magnitude of neuronal depletion in ROb was similar in DLB and MSA (49% versus 56% respectively, compared to controls, P < 0.05), but neuronal loss in the preBötC and RPa was less severe in DLB than in MSA (40% loss in preBötC of DLB, P < 0.05 and 68% loss in MSA, P < 0.0001, compared to controls; 46% loss in RPa of DLB, P < 0.05 and 73% loss in MSA P < 0.0001, compared to controls).. Medullary respiratory nuclei are affected in dementia with Lewy bodies but less severely than in multiple system atrophy. This may help explain differences in the frequency of sleep disordered breathing in these two disorders.

Topics: Aged, 80 and over; alpha-Synuclein; Case-Control Studies; Female; Humans; Lewy Body Disease; Male; Medulla Oblongata; Middle Aged; Multiple System Atrophy; Neurons; Receptors, Neurokinin-1; Sleep Apnea Syndromes; Tryptophan Hydroxylase

There is an unmet need for biomarkers for Parkinson's disease (PD) and atypical parkinsonian disorders (APD). α-Synuclein, linked to the pathogenesis of PD, is a promising biomarker candidate in need of further investigation. The ubiquitin carboxy-terminal hydrolase L1 (UCH-L1), a pivotal component of the ubiquitin proteasome system which seems to be disturbed in PD, may also be involved in the pathogenesis of this disorder.. We investigated cerebrospinal fluid (CSF) α-synuclein and UCH-L1 levels from 22 healthy controls, 52 patients with PD, 34 with multiple system atrophy (MSA), 32 with progressive supranuclear palsy, and 12 with corticobasal degeneration.. α-Synuclein levels were significantly decreased in PD and in MSA compared with controls, and in synucleinopathies compared with tauopathies. UCH-L1 levels were significantly decreased in PD, MSA as well as PSP compared with controls, and in PD compared with APD (p < 0.001). Both markers discriminated PD well from controls (p < 0.0001; area under the curve [AUC] = 0.82 and 0.89, respectively). Additionally, CSF α-synuclein separated patients with synucleinopathies from those with tauopathies (p = 0.015; AUC = 0.63), whereas CSF UCH-L1 discriminated between PD and APD (p = 0.0003; AUC = 0.69). Interestingly, α-synuclein and UCH-L1 levels were strongly correlated in PD and synucleinopathies, and weakly in tauopathies. No correlation was found in controls.. CSF levels of α-synuclein and UCH-L1 show distinct patterns in parkinsonian syndromes. Their combined determination may be useful in the differential diagnosis of parkinsonian disorders and provide key to understanding their pathoetiology and clinical course. Further large studies are needed to validate our findings.

Topics: Aged; alpha-Synuclein; Biomarkers; Enzyme-Linked Immunosorbent Assay; Female; Humans; Male; Middle Aged; Multiple System Atrophy; Parkinson Disease; Parkinsonian Disorders; Supranuclear Palsy, Progressive; Tauopathies; Ubiquitin Thiolesterase

Multiple system atrophy (MSA) is a progressive neurodegenerative disease presenting clinically with parkinsonian, cerebellar, and autonomic features. α-Synuclein (αsyn), encoded by the gene SNCA, is the main constituent of glial cytoplasmic inclusion (GCI) found in oligodendrocytes in MSA, but the methods of its accumulation have not been established. The aim of this study is to investigate alterations in regional and cellular SNCA mRNA expression in MSA as a possible substrate for GCI formation. Quantitative reverse transcription polymerase chain reaction (qPCR) was performed on postmortem brain samples from 15 MSA, 5 IPD, and 5 control cases to investigate regional expression in the frontal and occipital regions, dorsal putamen, pontine base, and cerebellum. For cellular expression analysis, neurons and oligodendrocytes were isolated by laser-capture microdissection from five MSA and five control cases. SNCA mRNA expression was not significantly different between the MSA, IPD and control cases in all regions (multilevel model, P = 0.14). After adjusting for group effect, the highest expression was found in the occipital cortex while the lowest was in the putamen (multilevel model, P < 0.0001). At the cellular level, MSA oligodendrocytes expressed more SNCA than control oligodendrocytes and expression in MSA neurons was slightly lower than that in controls, however, these results did not reach statistical significance. We have demonstrated regional variations in SNCA expression, which is higher in cortical than subcortical regions. This study is the first to demonstrate SNCA mRNA expression by oligodendrocytes in human postmortem tissue using qPCR and, although not statistically significant, could suggest that this may be increased in MSA compared to controls.

Topics: Aged; Aged, 80 and over; alpha-Synuclein; Brain; Cohort Studies; Female; Gene Expression Regulation; Humans; Male; Middle Aged; Multiple System Atrophy; Oligodendroglia; RNA, Messenger

Multiple system atrophy (MSA), an atypical parkinsonian disorder, is characterized by α-synuclein (α-syn(+)) cytoplasmatic inclusions in mature oligodendrocytes. Oligodendrocyte progenitor cells (OPCs) represent a distinct cell population with the potential to replace dysfunctional oligodendrocytes. However, the role of OPCs in MSA and their potential to replace mature oligodendrocytes is still unclear. A postmortem analysis in MSA patients revealed α-syn within OPCs and an increased number of striatal OPCs. In an MSA mouse model, an age-dependent increase of dividing OPCs within the striatum and the cortex was detected. Despite of myelin loss, there was no reduction of mature oligodendrocytes in the corpus callosum or the striatum. Dissecting the underlying molecular mechanisms an oligodendroglial cell line expressing human α-syn revealed that α-syn delays OPC maturation by severely downregulating myelin-gene regulatory factor and myelin basic protein. Brain-derived neurotrophic factor was reduced in MSA models and its in vitro supplementation partially restored the phenotype. Taken together, efficacious induction of OPC maturation may open the window to restore glial and neuronal function in MSA.

Topics: Aged; Aged, 80 and over; Aging; alpha-Synuclein; Animals; Cell Differentiation; Cell Proliferation; Cells, Cultured; Cerebral Cortex; Corpus Striatum; Disease Models, Animal; Female; Humans; Male; Mice, Transgenic; Middle Aged; Multiple System Atrophy; Oligodendroglia; Stem Cells

We describe the clinical, neuropathological, and genetic features of a Finnish patient with a novel α-synuclein (SNCA) mutation A53E. The patient was clinically diagnosed with atypical Parkinson's disease (PD) with age of onset at 36 years. In the neuropathological analysis performed at the age of 60 years, highly abundant SNCA pathology was observed throughout the brain and spinal cord showing features of multiple system atrophy and PD. Neuronal and glial (including oligodendroglial) SNCA inclusions and neurites were found to be particularly prominent in the putamen, caudatus, amygdala, temporal and insular cortices, gyrus cinguli, and hippocampus CA2-3 region. These areas as well as the substantia nigra and locus coeruleus showed neuronal loss and gliosis. We also found TDP-43 positive but mostly SNCA negative perinuclear inclusions in the dentate fascia of the hippocampus. The A53E mutation was found in 2 other relatives who had parkinsonism. Our results suggest that the novel SNCA A53E substitution is a causative mutation resulting clinically in parkinsonism and pathologically in severe multiple system atrophy- and PD-type phenotype.

Topics: Adult; alpha-Synuclein; Brain; DNA-Binding Proteins; Female; Genetic Association Studies; Humans; Middle Aged; Multiple System Atrophy; Mutation; Neurites; Parkinson Disease; Pedigree; Phenotype; Spinal Cord

Multiple system atrophy (MSA) is a neurodegenerative disease caused by α-synuclein aggregation in oligodendrocytes and neurons. Using a transgenic mouse model overexpressing human α-synuclein in oligodendrocytes, we previously demonstrated that oligodendrocytic α-synuclein inclusions induce neuronal α-synuclein accumulation and progressive neuronal degeneration. α-Synuclein binds to β-III tubulin, leading to the neuronal accumulation of insoluble α-synuclein in an MSA mouse model. The present study demonstrates that α-synuclein co-localizes with β-III tubulin in the brain tissue from patients with MSA and MSA model transgenic mice as well as neurons cultured from these mice. Accumulation of insoluble α-synuclein in MSA mouse neurons was blocked by the peptide fragment β-III tubulin (residues 235-282). We have determined the α-synuclein-binding domain of β-III tubulin and demonstrated that a short fragment containing this domain can suppress α-synuclein accumulation in the primary cultured cells. Administration of a short α-synuclein-binding fragment of β-III tubulin may be a novel therapeutic strategy for MSA.

Topics: alpha-Synuclein; Animals; Base Sequence; Cells, Cultured; Disease Models, Animal; DNA Primers; Mice; Mice, Transgenic; Multiple System Atrophy; Neurons; Protein Binding; Tubulin

Previous studies found that polymorphisms rs2736990 and rs356220 in the alpha-synuclein (SNCA) gene increase the risk for Parkinson's disease (PD) in a Caucasian population. In consideration of the overlapping of clinical manifestations and pathologic characteristics among PD, amyotrophic lateral sclerosis (ALS), and multiple system atrophy (MSA), the possible associations of these 2 polymorphisms and 3 neurodegenerative diseases were studied in the Chinese population. A total of 1011 PD, 778 sporadic ALS (SALS), 264 MSA patients, and 721 healthy controls (HCs) were studied. All subjects were genotyped for the 2 polymorphisms using polymerase chain reaction and direct sequencing. Significant differences in the genotype frequencies (p = 0.0188 and 0.0064, respectively) and minor allele frequencies (MAFs) (p = 0.0065 and 0.0095, respectively) of rs2736990 and rs356220 were observed between the PD patients and HCs. Moreover, significant differences were found between the early-onset PD patients (<50 years) and matched controls but not in the late-onset PD patients (≥50 years). However, no differences were observed between subgroups with regard to clinical features, such as sex, onset symptoms (tremor or rigidity), cognition (normal or abnormal), and anxiety and depression (presence or absence). No significant differences were found in the genotype frequencies and MAFs of these 2 single-nucleotide polymorphisms between SALS patients and HCs and between MSA patients and HCs. No significant differences were found between subgroups with regard to the clinical presentation of SALS and MSA. Our results show that rs2736990 and rs356220 in SNCA decreased the risk for PD in a Chinese population. These candidate polymorphisms were unlikely to be the causes of SALS and MSA in this population.

Topics: Aged; alpha-Synuclein; Amyotrophic Lateral Sclerosis; Asian People; Female; Genetic Association Studies; Genetic Predisposition to Disease; Humans; Male; Middle Aged; Multiple System Atrophy; Parkinson Disease; Polymorphism, Genetic; Risk Factors

Multiple system atrophy (MSA) is a rapidly-progressive neurodegenerative disease characterized by parkinsonism, cerebellar ataxia and autonomic failure. A pathological hallmark of MSA is the presence of α-synuclein deposits in oligodendrocytes, the myelin-producing support cells of the brain. Brain pathology and in vitro studies indicate that myelin instability may be an early event in the pathogenesis of MSA. Lipid is a major constituent (78% w/w) of myelin and has been implicated in myelin dysfunction in MSA. However, changes, if any, in lipid level/distribution in MSA brain are unknown. Here, we undertook a comprehensive analysis of MSA myelin. We quantitatively measured three groups of lipids, sphingomyelin, sulfatide and galactosylceramide, which are all important in myelin integrity and function, in affected (under the motor cortex) and unaffected (under the visual cortex) white matter regions. For all three groups of lipids, most of the species were severely decreased (40-69%) in affected but not unaffected MSA white matter. An analysis of the distribution of lipid species showed no significant shift in fatty acid chain length/content with MSA. The decrease in lipid levels was concomitant with increased α-synuclein expression. These data indicate that the absolute levels, and not distribution, of myelin lipids are altered in MSA, and provide evidence for myelin lipid dysfunction in MSA pathology. We propose that dysregulation of myelin lipids in the course of MSA pathogenesis may trigger myelin instability.

Topics: Aged; Aged, 80 and over; alpha-Synuclein; Brain Chemistry; Female; Galactosylceramides; Glycolipids; Humans; Male; Middle Aged; Multiple System Atrophy; Myelin Sheath; Sphingomyelins; Sulfoglycosphingolipids; White Matter

We report a British family with young-onset Parkinson's disease (PD) and a G51D SNCA mutation that segregates with the disease. Family history was consistent with autosomal dominant inheritance as both the father and sister of the proband developed levodopa-responsive parkinsonism with onset in their late thirties. Clinical features show similarity to those seen in families with SNCA triplication and to cases of A53T SNCA mutation. Post-mortem brain examination of the proband revealed atrophy affecting frontal and temporal lobes in addition to the caudate, putamen, globus pallidus and amygdala. There was severe loss of pigmentation in the substantia nigra and pallor of the locus coeruleus. Neuronal loss was most marked in frontal and temporal cortices, hippocampal CA2/3 subregions, substantia nigra, locus coeruleus and dorsal motor nucleus of the vagus. The cellular pathology included widespread and frequent neuronal α-synuclein immunoreactive inclusions of variable morphology and oligodendroglial inclusions similar to the glial cytoplasmic inclusions of multiple system atrophy (MSA). Both inclusion types were ubiquitin and p62 positive and were labelled with phosphorylation-dependent anti-α-synuclein antibodies In addition, TDP-43 immunoreactive inclusions were observed in limbic regions and in the striatum. Together the data show clinical and neuropathological similarities to both the A53T SNCA mutation and multiplication cases. The cellular neuropathological features of this case share some characteristics of both PD and MSA with additional unique striatal and neocortical pathology. Greater understanding of the disease mechanism underlying the G51D mutation could aid in understanding of α-synuclein biology and its impact on disease phenotype.

Topics: Adult; Age Factors; alpha-Synuclein; Humans; Male; Middle Aged; Multiple System Atrophy; Mutation; Parkinson Disease; Young Adult

Multiple system atrophy (MSA) is an adult-onset neurodegenerative disorder presenting with motor impairment and autonomic dysfunction. Urological function is altered in the majority of MSA patients, and urological symptoms often precede the motor syndrome. To date, bladder function and structure have never been investigated in MSA models. We aimed to test bladder function in a transgenic MSA mouse featuring oligodendroglial α-synucleinopathy and define its applicability as a preclinical model to study urological failure in MSA. Experiments were performed in proteolipid protein (PLP)-human α-synuclein (hαSyn) transgenic and control wild-type mice. Diuresis, urodynamics, and detrusor strip contractility were assessed to characterize the urological phenotype. Bladder morphology and neuropathology of the lumbosacral intermediolateral column and the pontine micturition center (PMC) were analyzed in young and aged mice. Urodynamic analysis revealed a less efficient and unstable bladder in MSA mice with increased voiding contraction amplitude, higher frequency of nonvoiding contractions, and increased postvoid residual volume. MSA mice bladder walls showed early detrusor hypertrophy and age-related urothelium hypertrophy. Transgenic hαSyn expression was detected in Schwann cells ensheathing the local nerve fibers in the lamina propria and muscularis of MSA bladders. Early loss of parasympathetic outflow neurons and delayed degeneration of the PMC accompanied the urological deficits in MSA mice. PLP-hαSyn mice recapitulate major urological symptoms of human MSA that may be linked to αSyn-related central and peripheral neuropathology and can be further used as a preclinical model to decipher pathomechanisms of MSA.

Topics: Acetylcholine; Age Factors; alpha-Synuclein; Animals; Brain; Disease Models, Animal; Disease Progression; Diuresis; Female; Gene Expression Regulation; Humans; Image Cytometry; In Vitro Techniques; Male; Mice; Mice, Inbred C57BL; Mice, Transgenic; Multiple System Atrophy; Myelin Proteolipid Protein; Urinary Bladder; Urinary Bladder Diseases; Uterine Contraction

Mutations in the gene encoding the F-box only protein 7 (FBXO7) cause PARK15, an autosomal recessive form of juvenile parkinsonism. Although the brain pathology in PARK15 patients remains unexplored, in vivo imaging displays severe loss of nigrostriatal dopaminergic terminals. Understanding the pathogenesis of PARK15 might therefore illuminate the mechanisms of the selective dopaminergic neuronal degeneration, which could also be important for understanding idiopathic Parkinson disease (PD). The expression of FBXO7 in the human brain remains poorly characterized, and its expression in idiopathic PD and different neurodegenerative diseases has not been investigated. Here, we studied FBXO7 protein expression in brain samples of normal controls (n = 9) and from patients with PD (n = 13), multiple system atrophy (MSA) (n = 5), Alzheimer disease (AD) (n = 5), and progressive supranuclear palsy (PSP) (n = 5) using immunohistochemistry with 2 anti-FBXO7 antibodies. We detected widespread brain FBXO7 immunoreactivity, with the highest levels in neurons of the cerebral cortex, putamen, and cerebellum. There were no major differences between normal and PD brains overall, but FBXO7 immunoreactivity was detected in large proportions of α-synuclein-positive inclusions (Lewy bodies, Lewy neurites, glial cytoplasmic inclusions), where it colocalized with α-synuclein in PD and MSA cases. By contrast, weak FBXO7 immunoreactivity was occasionally detected in tau-positive inclusions in AD and PSP. These findings suggest a role for FBXO7 in the pathogenesis of the synucleinopathies.

Topics: Aged; Aged, 80 and over; alpha-Synuclein; Brain; F-Box Proteins; Female; HEK293 Cells; Humans; Inclusion Bodies; Male; Middle Aged; Multiple System Atrophy; Parkinson Disease

Increasing evidence suggests that olfaction is largely preserved in multiple system atrophy while most patients with Parkinson's disease are hyposmic. Consistent with these observations, recent experimental studies demonstrated olfactory deficits in transgenic Parkinson's disease mouse models, but corresponding data are lacking for MSA models.. Olfactory function and underlying neuropathological changes were investigated in a transgenic multiple system atrophy mouse model based on targeted oligodendroglial overexpression of α-synuclein as well as wild-type controls. The study was divided into (1) a pilot study investigating olfactory preference testing and (2) a long-term study characterizing changes in the olfactory bulb of aging transgenic multiple system atrophy mice.. In our pilot behavioral study, we observed no significant differences in investigation time in the olfactory preference test comparing transgenic with wild-type animals. These findings were accompanied by unaffected tyrosine hydroxylase-positive cell numbers in the olfactory bulb. Similarly, although a significant age-related increase in the amount of α-synuclein within the olfactory bulb was detected in the long-term study, progressive degeneration of the olfactory bulb could not be verified.. Our experimental data show preserved olfaction in a transgenic multiple system atrophy mouse model despite α-synucleinopathy in the olfactory bulb. These findings are in line with the human disorder supporting the concept of a primary oligodendrogliopathy with variable neuronal involvement.

Topics: Age Factors; alpha-Synuclein; Analysis of Variance; Animals; DNA Primers; Fluorescent Antibody Technique; Genotype; Image Processing, Computer-Assisted; Immunohistochemistry; Mice; Mice, Transgenic; Multiple System Atrophy; Olfactory Bulb; Oligodendroglia; Polymerase Chain Reaction; Smell

We evaluated the immunohistochemical intensities of α-synuclein, phosphorylated α-synuclein (p-syn), dopamine- and cAMP-regulated phosphoprotein of 32 kDa (DARPP-32), calbindin-D 28k, calpain-cleaved carboxy-terminal 150-kDa spectrin fragment, and tyrosine hydroxylase in multiple system atrophy (MSA). The caudate head, anterior putamen, posterior putamen, substantia nigra, pontine nucleus, and cerebellar cortex from six MSA brains, six age-matched disease control brains (amyotrophic lateral sclerosis), and five control brains were processed for immunostaining by standard methods. Immunostaining for α-synuclein, p-syn, or both was increased in all areas examined in oligodendrocytes in MSA. Immunostaining for DARPP-32 and calbindin-D 28k was most prominently decreased in the posterior putamen, where neuronal loss was most prominent. Immunostaining for DARPP-32 and calbindin-D 28k was also diminished in the anterior putamen and caudate head, where neuronal loss was less prominent or absent. Calbindin immunostaining was also decreased in the dorsal tier of the substantia nigra and cerebellar cortex. Loss of immunostaining for DARPP-32 and calbindin-D 28k compared with that of neurons indicates calcium toxicity and disturbance of the phosphorylated state of proteins as relatively early events in the pathogenesis of MSA.

Topics: Aged; Aged, 80 and over; alpha-Synuclein; Brain; Calbindin 1; Case-Control Studies; Dopamine and cAMP-Regulated Phosphoprotein 32; Female; Humans; Male; Middle Aged; Multiple System Atrophy; Tyrosine 3-Monooxygenase

Microglia are resident immunosurveillant cells in the central nervous system, and astrocytes are important for blood flow, plasticity, and neurotransmitter regulation. The aim of this study was to investigate whether astrocyte and microglial activation, estimated through markers in cerebrospinal fluid and serum, differed between synucleinopathies, tauopathies, and controls.. We analyzed the glial activation markers YKL-40 and soluble CD14 in serum and cerebrospinal fluid from 37 controls, 50 patients with Parkinson's disease (PD), and 79 P+ patients (those with progressive supranuclear palsy, corticobasal degeneration, and multiple system atrophy).. Cerebrospinal fluid levels of YKL-40 were decreased significantly in patients who had PD compared with controls (P < 0.05), patients who had multiple system atrophy (P < 0.01), and patients who had tauopathies (P < 0.0001). In addition, cerebrospinal fluid levels of YKL-40 were significantly lower in patients who had synucleinopathies than in those who had tauopathies (P < 0.0001).. The decreased cerebrospinal fluid levels of YKL-40 suggest that glial activation is reduced in the brains of patients who have Parkinson's disease and synucleinopathies compared with patients who have tauopathies and controls.

Topics: Adipokines; Aged; alpha-Synuclein; Analysis of Variance; Basal Ganglia Diseases; Chitinase-3-Like Protein 1; Female; Humans; Lectins; Lipopolysaccharide Receptors; Male; Middle Aged; Multiple System Atrophy; Neurodegenerative Diseases; Parkinson Disease; Supranuclear Palsy, Progressive; Tauopathies

Multiple system atrophy (MSA) is a fatal neurodegenerative disease of unknown aetiology characterised by the accumulation of insoluble α-synuclein (α-syn) aggregates in the cytoplasm of myelin-producing oligodendrocytes. Dysfunction of the lipid-rich myelin membrane may precede α-syn pathology in MSA pathogenesis. ATP-binding cassette transporter A8 (ABCA8) is a little-studied lipid transporter, which has recently been found to be highly expressed in oligodendrocyte-rich white matter regions of the human brain. ABCA8 expression promotes sphingomyelin production in oligodendrocytes in vitro, suggesting a role in myelin formation and maintenance.. We hypothesise that aberrant ABCA8 expression in oligodendrocytes plays a role in the early pathogenesis of MSA by impacting myelin stability and regulation of α-syn and p25α.. We measured the expression of ABCA8, α-syn and p25α in MSA brains in disease-affected grey matter (GM, putamen and cerebellum), disease-affected white matter (WM, under the motor cortex) and an unaffected brain region (visual cortex). We transfected human oligodendrocytes with ABCA8 and assessed its impact on α-syn and p25α expression.. ABCA8 expression was significantly increased in the disease-affected GM and WM with no significant change in the unaffected brain region. α-syn and p25α expression were significantly increased in the disease-affected WM and GM respectively. Overexpression of ABCA8 in oligodendrocytes caused significant increases in both α-syn and p25α expression.. These data suggest a direct relationship between the levels of ABCA8 and the ectopic expression of α-syn and increased expression of p25α. As these data reflect results found in MSA, we hypothesise that increased ABCA8 may precipitate MSA pathology.

Topics: Aged; Aged, 80 and over; alpha-Synuclein; ATP-Binding Cassette Transporters; Brain Chemistry; Cells, Cultured; Computer Systems; Female; Homeostasis; Humans; Male; Middle Aged; Multiple System Atrophy; Myelin Sheath; Nerve Tissue Proteins; Oligodendroglia; RNA; Transfection

Prions are proteins that adopt alternative conformations, which become self-propagating. Increasing evidence argues that prions feature in the synucleinopathies that include Parkinson's disease, Lewy body dementia, and multiple system atrophy (MSA). Although TgM83(+/+) mice homozygous for a mutant A53T α-synuclein transgene begin developing CNS dysfunction spontaneously at ∼10 mo of age, uninoculated TgM83(+/-) mice (hemizygous for the transgene) remain healthy. To determine whether MSA brains contain α-synuclein prions, we inoculated the TgM83(+/-) mice with brain homogenates from two pathologically confirmed MSA cases. Inoculated TgM83(+/-) mice developed progressive signs of neurologic disease with an incubation period of ∼100 d, whereas the same mice inoculated with brain homogenates from spontaneously ill TgM83(+/+) mice developed neurologic dysfunction in ∼210 d. Brains of MSA-inoculated mice exhibited prominent astrocytic gliosis and microglial activation as well as widespread deposits of phosphorylated α-synuclein that were proteinase K sensitive, detergent insoluble, and formic acid extractable. Our results provide compelling evidence that α-synuclein aggregates formed in the brains of MSA patients are transmissible and, as such, are prions. The MSA prion represents a unique human pathogen that is lethal upon transmission to Tg mice and as such, is reminiscent of the prion causing kuru, which was transmitted to chimpanzees nearly 5 decades ago.

Topics: Aged; Aged, 80 and over; alpha-Synuclein; Animals; Disease Transmission, Infectious; Humans; Male; Mice; Mice, Transgenic; Multiple System Atrophy; Prions

Multiple system atrophy is a neurodegenerative disorder characterized pathologically by abnormal accumulations of α-synuclein in the cytoplasm of oligodendrocytes, which are termed glial cytoplasmic inclusions (GCIs). Oligodendrocytes are responsible for myelinating axons and providing neurotrophic support, but in MSA, myelin loss, axonal loss and gliosis are consistent features suggesting that GCIs play a central role in disease pathogenesis. Oligodendroglial, myelin and axonal degeneration are also features of multiple sclerosis (MS) in which recent studies have highlighted the robust remyelination capacity of the central nervous system (CNS). The cells responsible for remyelination are called oligodendroglial precursor cells (OPCs). In this study, we investigated the role of OPCs in the pathogenesis of MSA and progressive supranuclear palsy (PSP), a neurodegenerative disease in which neuropathological changes include oligodendroglial inclusions composed of microtubule-associated protein tau. Despite the lability of OPC-specific antigens, we successfully identified OPCs and demonstrated that tau and α-synuclein do not accumulate in OPCs. We also showed that the density of OPCs was increased in a white matter region of the MSA brain, which is also severely affected by GCIs and myelin degeneration. These findings raise the possibility that OPCs could be available to repair disease-associated damage in MSA, consistent with their biological function.

Topics: Aged; Aged, 80 and over; alpha-Synuclein; Axons; Cerebellum; Chondroitin Sulfate Proteoglycans; Female; Fluorescent Antibody Technique, Indirect; Gliosis; Humans; Image Processing, Computer-Assisted; Immunohistochemistry; Inclusion Bodies; Male; Middle Aged; Multiple System Atrophy; Myelin Sheath; Oligodendroglia; Parkinson Disease; Supranuclear Palsy, Progressive; tau Proteins

In 1817, James Parkinson described the symptoms of the shaking palsy, a disease that was subsequently defined in greater detail, and named after Parkinson, by Jean-Martin Charcot. Parkinson expected that the publication of his monograph would lead to a rapid elucidation of the anatomical substrate of the shaking palsy; in the event, this process took almost a century. In 1912, Fritz Heinrich Lewy identified the protein aggregates that define Parkinson disease (PD) in some brain regions outside the substantia nigra. In 1919, Konstantin Nikolaevich Tretiakoff found similar aggregates in the substantia nigra and named them after Lewy. In the 1990s, α-synuclein was identified as the main constituent of the Lewy pathology, and its aggregation was shown to be central to PD, dementia with Lewy bodies, and multiple system atrophy. In 2003, a staging scheme for idiopathic PD was introduced, according to which α-synuclein pathology originates in the dorsal motor nucleus of the vagal nerve and progresses from there to other brain regions, including the substantia nigra. In this article, we review the relevance of Lewy's discovery 100 years ago for the current understanding of PD and related disorders.

Topics: alpha-Synuclein; Brain; Germany; History, 19th Century; History, 20th Century; History, 21st Century; Humans; Lewy Body Disease; Multiple System Atrophy; Parkinson Disease

Multiple system atrophy (MSA) is a neurodegenerative disorder characterised by autonomic dysfunction with parkinsonism (MSAp) or cerebellar (MSAc) symptoms. At autopsy, α-synuclein inclusions in glial cells of the brain are needed to confirm a definite diagnosis. We determined the 10 year incidence of MSA, point prevalence and survival in a well defined population with a high number of neurologists.. Cases were identified from the only neurology department and all practising neurologists in Iceland, over a 10 year period. The diagnosis of MSA was in accordance with the Second Consensus Criteria of MSA.. 19 incidence cases were diagnosed with MSA (11 women, eight men) during the study period, giving an average annual incidence of 0.7:100 000 (95% CI 0.4 to 1.1). Ten cases were alive on the prevalence day, giving a point prevalence of 3.4:100 000 (95% CI 1.6 to 6.3). 16 of the cases had probable and three possible MSA; 16 had MSAp and three had MSAc. Mean age at symptom onset was 65 years and mean age at diagnosis was 68 years. Patients were followed for an average of 31 months, and 15 died during the follow-up period. Survival from symptom onset was mean 5.7 years. The 1 and 5 year survival rates from diagnosis were 74% and 28%, respectively.. We reported on the incidence of MSA (both MSAp and MSAc) in a nationwide study where a definite diagnosis of MSA was confirmed in four out of five patients autopsied. We found survival to be shorter than reported in other studies.

Topics: Age of Onset; Aged; Aged, 80 and over; alpha-Synuclein; Brain; Female; Humans; Iceland; Incidence; Male; Middle Aged; Multiple System Atrophy; Prevalence; Survival Rate

The clinical diagnosis of Parkinson disease (PD) is incorrect in 30% or more of subjects particularly at the time of symptom onset. Because Lewy-type α-synucleinopathy is present in the submandibular glands of PD patients, we assessed the feasibility of submandibular gland biopsy for diagnosing PD. We performed immunohistochemical staining for Lewy-type α-synucleinopathy in sections of large segments (simulating open biopsy) and needle cores of submandibular glands from 128 autopsied and neuropathologically classified subjects, including 28 PD, 5 incidental Lewy body disease, 5 progressive supranuclear palsy (3 with concurrent PD), 3 corticobasal degeneration, 2 multiple system atrophy, 22 Alzheimer disease with Lewy bodies, 16 Alzheimer disease without Lewy bodies, and 50 normal elderly. Immunoreactive nerve fibers were present in large submandibular gland sections of all 28 PD subjects (including 3 that also had progressive supranuclear palsy); 3 Alzheimer disease with Lewy bodies subjects were also positive, but none of the other subjects were positive. Cores from frozen submandibular glands taken with 18-gauge needles (total length, 15-38 mm; between 10 and 118 sections per subject examined) were positive for Lewy-type α-synucleinopathy in 17 of 19 PD patients. These results suggest that biopsy of the submandibular gland may be a feasible means of improving PD clinical diagnostic accuracy. This would be particularly advantageous for subject selection in early-stage clinical trials for invasive therapies or for verifying other biomarker studies.

Topics: Aged; Aged, 80 and over; alpha-Synuclein; Biopsy; Brain; Female; Humans; Lewy Body Disease; Male; Multiple System Atrophy; Muscle, Smooth; Nerve Fibers; Parkinson Disease; Submandibular Gland; Supranuclear Palsy, Progressive

Multiple system atrophy is a parkinsonian neurodegenerative disorder. It is cytopathologically characterized by accumulation of the protein p25α in cell bodies of oligodendrocytes followed by accumulation of aggregated α-synuclein in so-called glial cytoplasmic inclusions. p25α is a stimulator of α-synuclein aggregation, and coexpression of α-synuclein and p25α in the oligodendroglial OLN-t40-AS cell line causes α-synuclein aggregate-dependent toxicity. In this study, we investigated whether the FAS system is involved in α-synuclein aggregate dependent degeneration in oligodendrocytes and may play a role in multiple system atrophy. Using rat oligodendroglial OLN-t40-AS cells we demonstrate that the cytotoxicity caused by coexpressing α-synuclein and p25α relies on stimulation of the death domain receptor FAS and caspase-8 activation. Using primary oligodendrocytes derived from PLP-α-synuclein transgenic mice we demonstrate that they exist in a sensitized state expressing pro-apoptotic FAS receptor, which makes them sensitive to FAS ligand-mediated apoptosis. Immunoblot analysis shows an increase in FAS in brain extracts from multiple system atrophy cases. Immunohistochemical analysis demonstrated enhanced FAS expression in multiple system atrophy brains notably in oligodendrocytes harboring the earliest stages of glial cytoplasmic inclusion formation. Oligodendroglial FAS expression is an early hallmark of oligodendroglial pathology in multiple system atrophy that mechanistically may be coupled to α-synuclein dependent degeneration and thus represent a potential target for protective intervention.

Topics: Aged; alpha-Synuclein; Animals; Brain; Cell Death; Fas Ligand Protein; fas Receptor; Gene Expression; Humans; Mice; Middle Aged; Multiple System Atrophy; Nerve Tissue Proteins; Oligodendroglia; Protein Binding; Protein Transport; Rats; Signal Transduction

Multiple system atrophy (MSA) is a fatal, rapidly progressive neurodegenerative disease with limited symptomatic treatment options. Discrimination of MSA from other degenerative disorders crucially depends on the presence of early and severe cardiovascular autonomic failure (CAF). We have previously shown that neuropathologic lesions in the central autonomic nuclei similar to the human disease are present in transgenic MSA mice generated by targeted oligodendroglial overexpression of α-syn using the PLP promoter. We here explore whether such lesions result in abnormalities of heart rate variability (HRV) and circadian rhythmicity which are typically impaired in MSA patients. HRV analysis was performed in five month old transgenic PLP-α-syn (tg) MSA mice and age-matched wild type controls. Decreased HRV and alterations in the circadian rhythmicity were detected in the tg MSA group. The number of choline-acetyltransferase-immunoreactive neurons in the nucleus ambiguus was significantly decreased in the tg group, whereas the levels of arginine-vasopressin neurons in the suprachiasmatic and paraventricular nucleus were not affected. Our finding of impaired HRV and circadian rhythmicity in tg MSA mice associated with degeneration of the nucleus ambiguus suggests that a cardinal non-motor feature of human MSA can be reproduced in the mouse model strengthening its role as a valuable testbed for studying selective vulnerability and assessing translational therapies.

Topics: alpha-Synuclein; Analysis of Variance; Animals; Arginine Vasopressin; Body Temperature; Cardiovascular Abnormalities; Choline O-Acetyltransferase; Disease Models, Animal; Electrocardiography; Electroencephalography; Heart Rate; Male; Mice; Mice, Inbred C57BL; Mice, Transgenic; Motor Activity; Multiple System Atrophy; Myelin Proteolipid Protein; Nucleus Accumbens; Oligodendroglia; Time Factors

Topics: alpha-Synuclein; Basal Ganglia; Cerebellar Diseases; Cerebellum; Dopamine; Female; Gait Disorders, Neurologic; Humans; Leukoencephalopathies; Magnetic Resonance Imaging; Middle Aged; Multiple System Atrophy; Receptors, Dopamine; Tomography, Emission-Computed, Single-Photon; Ubiquitin

We describe herein an autopsied case of multiple system atrophy (MSA) with prolonged clinical course of 18 years, and evaluate the extent of neurodegeneration and glial cytoplasmic inclusions (GCIs) in the entire brain of this rare case. A 64-year-old woman presented with typical neurological symptoms and imaging features of MSA. Thereafter, she became bedridden, and breathing was assisted through a tracheostomy for 12 years. She died at the age of 82 after 18 years from the initial symptom. Post mortem examination revealed severe neurodegeneration in the inferior olive, pontine nuclei, substantia nigra, locus ceruleus, putamen and cerebellum. Notably, phosphorylated α-synuclein (p-α-syn)-positive GCIs were found in these areas, but their number was very low. In contrast, the density of GCIs was much higher in such regions as the tectum/tegmentum of the brainstem, pyramidal tracts, neocortices and limbic system, which usually contain a small number of GCIs. Another constituent of GCIs, ubiquitin (Ub) and Ub-associated autophagy substrate p62, were also positive in some GCIs, and distribution of Ub/p62 immunoreactivity was proportionate to that of p-α-syn+ GCIs despite the very long duration of the disease. Furthermore, this case had complicated hypoxic encephalopathy, but p-α-syn+ GCIs were also found in the damaged white matter, indicating the contribution of α-syncleinopathy as well as hypoxic effect to the secondary myelin and axonal loss in the white matter. Together, this rare case suggests the contribution of the disease duration to the prevalence of GCIs, and the possible involvement of the limbic system in extensive-stage disease.

Topics: Age of Onset; Aged, 80 and over; alpha-Synuclein; Brain; Female; Humans; Inclusion Bodies; Middle Aged; Multiple System Atrophy; Nerve Degeneration; Neuroglia; Ubiquitin

Differentiating clinically between Parkinson's disease (PD) and the atypical parkinsonian syndromes of Progressive supranuclear palsy (PSP), corticobasal syndrome (CBS) and multiple system atrophy (MSA) is challenging but crucial for patient management and recruitment into clinical trials. Because PD (and the related disorder Dementia with Lewy bodies (DLB)) and MSA are characterised by the deposition of aggregated forms of α-synuclein protein (α-syn) in the brain, whereas CBS and PSP are tauopathies, we have developed immunoassays to detect levels of total and oligomeric forms of α-syn, and phosphorylated and phosphorylated oligomeric forms of α-syn, within body fluids, in an attempt to find a biomarker that will differentiate between these disorders. Levels of these 4 different forms of α-syn were measured in post mortem samples of ventricular cerebrospinal fluid (CSF) obtained from 76 patients with PD, DLB, PSP or MSA, and in 20 healthy controls. Mean CSF levels of total and oligomeric α-syn, and phosphorylated α-syn, did not vary significantly between the diagnostic groups, whereas mean CSF levels of phosphorylated oligomeric α-syn did differ significantly (p<0.001) amongst the different diagnostic groups. Although all 4 measures of α-syn were higher in patients with MSA compared to all other diagnostic groups, these were only significantly raised (p<0.001) in MSA compared to all other diagnostic groups, for phosphorylated oligomeric forms of α-syn. This suggests that this particular assay may have utility in differentiating MSA from control subject and patients with other α-synucleinopathies. However, it does not appear to be of help in distinguishing patients with PD and DLB from those with PSP or from control subjects. Western blots show that the principal form of α-syn within CSF is phosphorylated, and the finding that the phosphorylated oligomeric α-syn immunoassay appears to be the most informative of the 4 assays would be consistent with this observation.

Topics: Aged; Aged, 80 and over; alpha-Synuclein; Biomarkers; Brain; Diagnosis, Differential; Female; Humans; Lewy Body Disease; Male; Middle Aged; Multiple System Atrophy; Parkinson Disease

Multiple system atrophy (MSA) is a rare and fatal α-synucleinopathy characterized by a distinctive oligodendrogliopathy with glial cytoplasmic inclusions and associated neuronal multisystem degeneration. The majority of patients presents with a rapidly progressive parkinsonian disorder and atypical features such as early autonomic failure and cerebellar ataxia. We have previously reported that complete MSA pathology can be modeled in transgenic mice overexpressing oligodendroglial α-synuclein under conditions of oxidative stress induced by 3-nitropropionic acid (3-NP) including striatonigral degeneration, olivopontocerebellar atrophy, astrogliosis, and microglial activation. Here, we show that myeloperoxidase (MPO), a key enzyme involved in the production of reactive oxygen species by phagocytic cells, is expressed in both human and mouse MSA brains. We also demonstrate that in the MSA mouse model, MPO inhibition reduces motor impairment and rescues vulnerable neurons in striatum, substantia nigra pars compacta, cerebellar cortex, pontine nuclei, and inferior olives. MPO inhibition is associated with suppression of microglial activation but does not affect 3-NP induced astrogliosis in the same regions. Finally, MPO inhibition results in reduced intracellular aggregates of α-synuclein. This study suggests that MPO inhibition may represent a novel candidate treatment strategy against MSA-like neurodegeneration acting through its anti-inflammatory and anti-oxidative properties.

Topics: Aged; alpha-Synuclein; Animals; Brain; Disease Models, Animal; Dose-Response Relationship, Drug; Enzyme Inhibitors; Gliosis; Humans; Male; Mice; Mice, Transgenic; Microglia; Middle Aged; Motor Activity; Multiple System Atrophy; Nerve Degeneration; Peroxidase; Pyrimidinones; Pyrroles

Multiple system atrophy (MSA) is a neurodegenerative disease caused by α-synuclein (α-syn) accumulation in oligodendrocytes and neurons. We generated a transgenic (Tg) mouse model in which human α-syn was overexpressed in oligodendrocytes. Our previous studies have revealed that oligodendrocytic α-syn inclusions induced neuronal α-syn accumulation, thereby resulting in progressive neuronal degeneration in mice. We also demonstrated that an insoluble complex of α-syn and β-III tubulin in microtubules progressively accumulated in neurons, thereby leading to neuronal degeneration. In the present study, we demonstrated that neuronal accumulation of the insoluble complex was derived from binding of α-syn to β-III tubulin and not from α-syn self-aggregation. Thus, interaction between α-syn and β-III tubulin plays an important role in neuronal α-syn accumulation in an MSA mouse model.

Topics: alpha-Synuclein; Animals; Cells, Cultured; Disease Models, Animal; Humans; Mice; Mice, Transgenic; Multiple System Atrophy; Neurons; Nocodazole; Polymerization; Protein Binding; Rifampin; Tubulin; Tubulin Modulators

Multiple system atrophy is a sporadic, progressive, neurodegenerative disease characterized by an oligodendroglial accumulation of alpha-synuclein (α-syn). The mechanisms underlying the oligodendroglial accumulation of α-syn in the brains of patients with multiple system atrophy have attracted a great deal of interest, given the primarily neuronal role reported for this protein. We examined the interactions between neuronal and oligodendroglial α-syn in the progeny of crosses between parental transgenic (tg) mouse lines that express α-syn either under the oligodendroglial-specific myelin-basic protein promoter (MBP1-hα-syn tg) or under the neuronal platelet-derived growth factor promoter (PDGF-hα-syn tg). Our results demonstrate that progeny from the cross [hα-syn double (dbl) tg mice] displayed a robust redistribution of α-syn accumulation, with a relocalization from a neuronal or a mixed neuronal/oligodendroglial α-syn expression to a more oligodendroglial pattern in both the neocortex and the basal ganglia that closely resembled the parental MBP-hα-syn tg line. The hα-syn dbl tg mice also displayed motor deficits, concomitant with reduced levels of tyrosine hydroxylase and augmented neuropathological alterations in the basal ganglia. These results suggest that the central nervous system milieu in the hα-syn dbl tg mice favors an oligodendroglial accumulation of α-syn. This model represents an important tool to examine the interactions between neuronal and oligodendrocytic α-syn in diseases such as multiple system atrophy.

Topics: alpha-Synuclein; Animals; Cell Communication; Disease Models, Animal; Female; Humans; Male; Mice; Mice, Transgenic; Multiple System Atrophy; Neurons; Oligodendroglia

α-Synuclein is the major protein associated with Lewy body dementia, Parkinson's disease and multiple system atrophy. Since α-synuclein is present in the brain in physiological conditions as a presynaptic protein, it is crucial to characterize disease-associated modifications to develop an in vivo biomarker. With the aim to develop antibodies showing high specificity and sensitivity for disease-associated α-synuclein, synthetic peptides containing different amino acid sequences were used for immunization of mice. After generation of α-synuclein aggregates, ELISA and immunoblotting were used to test the specificity of antibodies. Tissue microarray sections originating from different human α-synucleinopathies were used to compare immunostaining with other, commercially available antibodies. Immunization of mice with the peptide TKEGVVHGVATVAE (amino acid 44-57 of α-synuclein) resulted in the generation of a monoclonal antibody (5G4), which was able to bind aggregated α-synuclein preparation in sandwich ELISA or coated on magnetic beads. 5G4 proved to be superior to other antibodies in comparative immunohistochemical studies by revealing more widespread and distinct α-synuclein pathology. Immunoblotting of human brain tissue revealed an additional band seen in dementia with Lewy bodies, whereas the band representing monomeric α-synuclein was very weak or lacking. In summary, the 5G4 antibody is most promising for re-evaluation of archival material and may offer new perspective for the development of in vivo diagnostic assays for detecting disease-associated α-synuclein in body fluids.

Topics: alpha-Synuclein; Antibodies; Brain; Brain Diseases; Enzyme-Linked Immunosorbent Assay; Frontotemporal Lobar Degeneration; Humans; Immunohistochemistry; Multiple System Atrophy; Neurons; Parkinson Disease

α-Synuclein-containing glial cytoplasmic inclusions (GCIs) originating in oligodendrocytes are the characteristic hallmark for neuropathological diagnosis of multiple system atrophy (MSA). α-Synuclein can be degraded either by the proteasomal machinery or by autophagy, a lysosomal pathway which involves the formation of autophagosomes. The autophagosome takes up polyubiquitinated proteins via the autophagosomal protein LC3 and the ubiquitin binding protein p62. In the present study, neuropathological examination of seven MSA cases revealed that LC3-immunoreactivity is found to be associated with α-synuclein-positive GCIs. These are also prominently stained by antibodies against p62 and ubiquitin, indicating that the autophagic pathway is upregulated during pathogenesis, which might be due to a persistent downregulation of proteasomal activity. To further address this question in a cellular context, we have investigated whether proteasomal inhibition in cultured rat brain oligodendrocytes promotes the recruitment of LC3 and p62 to protein aggregates. The data show that the autophagic marker LC3-II is upregulated and LC3 is recruited to the growing protein aggregates in cultured oligodendrocytes when the proteasome is impaired. However, aggregated proteins remain in the oligodendroglial cytoplasm and cannot be cleared efficiently. In conclusion, autophagy and the ubiquitin proteasome system are closely connected, and the presence of LC3-positive vesicles in GCIs indicates that macroautophagy participates in MSA pathogenesis.

Topics: Adult; Aged; alpha-Synuclein; Animals; Autophagy; Cells, Cultured; Female; Humans; Inclusion Bodies; Male; Middle Aged; Multiple System Atrophy; Oligodendroglia; Rats

Routine colonic biopsies allow the detection of alpha-synuclein aggregates in the enteric nervous system (ENS) in living Parkinson's disease (PD) patients. Whether the ENS is affected by alpha-synuclein pathology in multiple system atrophy (MSA) has not been studied yet. The aim of the present research was therefore to analyze colonic biopsies in MSA for the presence of alpha-synuclein pathology. Six MSA and 9 PD patients were included. Four biopsies, taken from the descending colon during the course of a rectosigmoidscopy were microdissected, and analyzed by immunohistochemistry using antibodies against phosphorylated alpha-synuclein and neurofilaments NF 200 kDa. Aggregates of alpha-synuclein were detected in one out of 6 MSA patients and in 5 out of 9 PD patients. This demonstrates that, despite being less frequent than in PD, alpha-synuclein deposits can be observed in the ENS in MSA.

Topics: Aged; alpha-Synuclein; Biopsy; Colon; Enteric Nervous System; Female; Humans; Immunohistochemistry; Male; Middle Aged; Multiple System Atrophy; Parkinson Disease

To assess the ability of 5 cerebrospinal fluid(CSF) biomarkers to differentiate between common dementia and parkinsonian disorders.. A cross-sectional, clinic-based study.. Cerebrospinal fluid samples (N=453) were obtained from healthy individuals serving as controls and from patients with Parkinson disease (PD), PD with dementia(PDD), dementia with Lewy bodies (DLB), Alzheimer disease (AD), progressive supranuclear palsy(PSP), multiple system atrophy (MSA), or corticobasal degeneration (CBD).. Neurology and memory disorder clinics.. Cerebrospinal fluid biomarker levels in relation to clinical diagnosis.. Cerebrospinal fluid levels of -synuclein were decreased in patients with PD, PDD, DLB, and MSA but increased in patients with AD. Cerebrospinal fluid levels of α-amyloid 1-42 were decreased in DLB and even further decreased in AD. Cerebrospinal fluid levels of total tau and hyperphosphorylated tau were increased in AD. Multivariate analysis revealed that these biomarkers could differentiate AD from DLB and PDD with an area under the curve of 0.90, with -synuclein and total tau contributing most to the model. Cerebrospinal fluid levels of neurofilament light chain were substantially increased in atypical parkinsonian disorders (ie, PSP, MSA,and CBD), and multivariate analysis revealed that the level of neurofilament light chain alone could differentiate PD from atypical parkinsonian disorders, with an area under the curve of 0.93.. Ascertainment of the -synuclein level in CSF somewhat improves the differential diagnosis of AD vs DLB and PDD when combined with established AD biomarkers.The level of neurofilament light chain alone may differentiate PD from atypical parkinsonian disorders.

Topics: Aged; Aged, 80 and over; alpha-Synuclein; Amyloid beta-Peptides; Biomarkers; Cross-Sectional Studies; Dementia; Diagnosis, Differential; Enzyme-Linked Immunosorbent Assay; Female; Hemoglobins; Humans; Male; Middle Aged; Multiple System Atrophy; Neurodegenerative Diseases; Neuropsychological Tests; Parkinson Disease; Psychiatric Status Rating Scales; Severity of Illness Index; Statistics, Nonparametric; Supranuclear Palsy, Progressive; tau Proteins

Multiple system atrophy (MSA) is a progressive neurodegenerative disorder characterized by striatonigral degeneration and olivo-pontocerebellar atrophy. The histopathological hallmark of MSA is glial cytoplasmic inclusions (GCI) within oligodendrocytes, accompanied by neuronal degeneration. MSA is a synucleinopathy, and α-Synuclein (α-Syn) is the major protein constituent of the GCI. It is unclear how the neuronal α-Syn protein accumulates in oligodendrocytes. We tested the hypothesis that oligodendrocytes can take up neuronal-secreted α-Syn as part of the pathogenic mechanisms leading to MSA. We report that increases in the degree of α-Syn soluble oligomers or intracellular α-Syn levels, enhance its secretion from cultured MN9D dopaminergic cells, stably expressing the protein. In accord, we show that primary oligodendrocytes from rat brain and oligodendroglial cell lines take-up neuronal-secreted or exogenously added α-Syn from their conditioning medium. This uptake is concentration-, time-, and clathrin-dependent. Utilizing the demonstrated effect of polyunsaturated fatty acids (PUFA) to enhance α-Syn neuropathology, we show an in vivo effect for brain docosahexaenoic acid (DHA) levels on α-Syn localization to oligodendrocytes in brains of a mouse model for synucleinopathies, expressing human A53T α-Syn cDNA under the PrP promoter. Hence, pathogenic mechanisms leading to elevated levels of α-Syn in neurons underlie neuronal secretion and subsequent uptake of α-Syn by oligodendrocytes in MSA.

Topics: alpha-Synuclein; Animals; Brain; Cell Line; Cells, Cultured; Clathrin; Docosahexaenoic Acids; Fatty Acids, Unsaturated; Gene Expression; Humans; Mice; Mice, Inbred C57BL; Multiple System Atrophy; Oligodendroglia; Rats; Transfection

Multiple system atrophy is a neurodegenerative disease caused by abnormal α-synuclein (α-syn) accumulation in oligodendrocytes and neurons. We previously demonstrated that transgenic (Tg) mice that selectively overexpressed human α-syn in oligodendrocytes exhibited neuronal α-syn accumulation. Microtubule β-III tubulin binds to endogenous neuronal α-syn to form an insoluble complex, leading to progressive neuronal degeneration. α-Syn accumulation is increased in the presynaptic terminals of Tg mice neurons and may reduce neurotransmitter release. To clarify the mechanisms underlying its involvement in neuronal dysfunction, in the present study, we investigated the effects of neuronal α-syn accumulation on synaptic function in Tg mice. Using whole-cell patch-clamp recording, we found that the frequency of miniature inhibitory postsynaptic currents was reduced in Tg mice. Furthermore, a microtubule depolymerizing agent restored normal frequencies of miniature inhibitory postsynaptic currents in Tg mice. These findings suggest that α-syn and β-III tubulin protein complex plays roles for regulation of synaptic vesicle release in GABAergic interneurons, and it causes to reduce GABAergic inhibitory transmission.

Topics: alpha-Synuclein; Animals; GABAergic Neurons; Humans; Mice; Mice, Transgenic; Microtubules; Multiple System Atrophy; Synaptic Transmission; Tubulin

Multiple system atrophy (MSA) is a sporadic neurodegenerative disease that is pathologically characterized by the filamentous aggregation of α-synuclein. We report a case of MSA showing unusual neuropathological findings and review six autopsied cases of MSA. The patient progressively developed parkinsonism and ataxia for the 9 years prior to her death at the age of 72 years. Neuropathological examinations revealed neuronal loss restricted to the olivopontocerebellar and striatonigral region, which was more severe in the putamen. Staining with anti-α-synuclein antibody demonstrated widespread occurrence of glial cytoplasmic inclusions, which mainly accumulated in oligodendroglial cells and corresponded closely to the degree of disease progression. In addition, tau-positive granules were detected within the glial cytoplasm in the neurodegenerative region, which was especially prominent in the putamen and internal capsule. Tau accumulation was also clearly recognized by staining with specific antibodies against three-repeat or four-repeat tau. The glia that demonstrated deposition of tau-positive granules were distinguished from α-synuclein-positive oligodendroglia by double immunohistochemical staining. These characteristic glial accumulations of tau were also present in all six cases of MSA. These results indicate that tau-positive granules in glia are common findings in MSA and that tau aggregation might be another pathway to neurodegeneration in MSA.

Topics: Aged; alpha-Synuclein; Cytoplasmic Granules; Fatal Outcome; Female; Humans; Male; Middle Aged; Multiple System Atrophy; Nerve Degeneration; Neuroglia; Olivary Nucleus; Substantia Nigra; tau Proteins

The aggregation of α-synuclein (αS) in the central nervous system (CNS) is the hallmark of multiple system atrophy (MSA) and Lewy body diseases including Parkinson's disease (PD) and dementia with Lewy bodies (DLB) (α-synucleinopathies). To test the hypothesis that patients with α-synucleinopathies have a CNS environment favorable for αS aggregation, we examined the influence of cerebrospinal fluid (CSF) from patients with MSA (n=20), DLB (n=8), and PD (n=10) on in vitro αS fibril (fαS) formation at pH 7.5 and 37°C using fluorescence spectroscopy with thioflavin S, compared with those with hereditary spinocerebellar ataxia (hSCA) (n=16), and tension-type headache (n=7). CSF from MSA patients (MSA-CSF) promoted fαS formation more strongly than PD-, hSCA-, or headache-CSF. By electron microscopic analyses, the width of fαS formed in MSA-CSF was significantly greater than others. MSA may have a CSF environment particularly favorable for fαS formation.

Topics: Adult; Aged; Aged, 80 and over; alpha-Synuclein; Cerebrospinal Fluid; Female; Humans; Male; Middle Aged; Multiple System Atrophy; Nerve Degeneration; Neurofibrils; Spinocerebellar Ataxias; Tension-Type Headache

Parkinson's disease, dementia with Lewy bodies, and multiple system atrophy are brain disorders characterised by intracellular α-synuclein deposits. We aimed to assess whether reduction of α-synuclein concentrations in CSF was a marker for α-synuclein deposition in the brain, and therefore diagnostic of synucleinopathies.. We assessed potential extracellular-fluid markers of α-synuclein deposition in the brain (total α-synuclein and total tau in CSF, and total α-synuclein in serum) in three cohorts: a cross-sectional training cohort of people with Parkinson's disease, multiple system atrophy, dementia with Lewy bodies, Alzheimer's disease, or other neurological disorders; a group of patients with autopsy-confirmed dementia with Lewy bodies, Alzheimer's disease, or other neurological disorders (CSF specimens were drawn ante mortem during clinical investigations); and a validation cohort of patients who between January, 2003, and December, 2006, were referred to a specialised movement disorder hospital for routine inpatient admission under the working diagnosis of parkinsonism. CSF and serum samples were assessed by ELISA, and clinical diagnoses were made according to internationally established criteria. Mean differences in biomarkers between diagnostic groups were assessed with conventional parametric and non-parametric statistics.. In our training set, people with Parkinson's disease, multiple system atrophy, and dementia with Lewy bodies had lower CSF α-synuclein concentrations than patients with Alzheimer's disease and other neurological disorders. CSF α-synuclein and tau values separated participants with synucleinopathies well from those with other disorders (p<0·0001; area under the receiver operating characteristic curve [AUC]=0·908). In the autopsy-confirmed cases, CSF α-synuclein discriminated between dementia with Lewy bodies and Alzheimer's disease (p=0·0190; AUC=0·687); in the validation cohort, CSF α-synuclein discriminated Parkinson's disease and dementia with Lewy bodies versus progressive supranuclear palsy, normal-pressure hydrocephalus, and other neurological disorders (p<0·0001; AUC=0·711). Other predictor variables tested in this cohort included CSF tau (p=0·0798), serum α-synuclein (p=0·0502), and age (p=0·0335). CSF α-synuclein concentrations of 1·6 pg/μL or lower showed 70·72% sensitivity (95% CI 65·3-76·1%) and 52·83% specificity (39·4-66·3%) for the diagnosis of Parkinson's disease. At this cutoff, the positive predictive value for any synucleinopathy was 90·7% (95% CI 87·3-94·2%) and the negative predictive value was 20·4% (13·7-27·2%).. Mean CSF α-synuclein concentrations as measured by ELISA are significantly lower in Parkinson's disease, dementia with Lewy bodies, and multiple system atrophy than in other neurological diseases. Although specificity was low, the high positive predictive value of CSF α-synuclein concentrations in patients presenting with synucleinopathy-type parkinsonism might be useful in stratification of patients in future clinical trials.. American Parkinson Disease Association, Stifterverband für die Deutsche Wissenschaft, Michael J Fox Foundation for Parkinson's Research, National Institutes of Health, Parkinson Research Consortium Ottawa, and the Government of Canada.

Topics: Adult; Aged; Aged, 80 and over; alpha-Synuclein; Alzheimer Disease; Biomarkers; Cohort Studies; Cross-Sectional Studies; Female; Humans; Lewy Body Disease; Male; Middle Aged; Multiple System Atrophy; Parkinson Disease; tau Proteins

There is a clear need to develop biomarkers for Parkinson disease (PD) diagnosis, differential diagnosis of Parkinsonian disorders, and monitoring disease progression. We and others have demonstrated that a decrease in DJ-1 and/or α-synuclein in the cerebrospinal fluid (CSF) is a potential index for Parkinson disease diagnosis, but not for PD severity.. Using highly sensitive and quantitative Luminex assays, we measured total tau, phosphorylated tau, amyloid beta peptide 1-42 (Aβ(1-42)), Flt3 ligand, and fractalkine levels in CSF in a large cohort of PD patients at different stages as well as healthy and diseased controls. The utility of these 5 markers was evaluated for disease diagnosis and severity/progression correlation alone, as well as in combination with DJ-1 and α-synuclein. The major results were further validated in an independent cohort of cross-sectional PD patients as well as in PD cases with CSF samples collected longitudinally.. The results demonstrated that combinations of these biomarkers could differentiate PD patients not only from normal controls but also from patients with Alzheimer disease (AD) and multiple system atrophy. Particularly, with CSF Flt3 ligand, PD could be clearly differentiated from multiple system atrophy, a disease that overlaps with PD clinically, with excellent sensitivity (99%) and specificity (95%). In addition, we identified CSF fractalkine/Aβ(1-42) that positively correlated with PD severity in cross-sectional samples as well as with PD progression in longitudinal samples.. We have demonstrated that this panel of 7 CSF proteins could aid in Parkinson disease diagnosis, differential diagnosis, and correlation with disease severity and progression.

Topics: alpha-Synuclein; Alzheimer Disease; Amyloid beta-Peptides; Analysis of Variance; Biomarkers; Chemokine CX3CL1; Diagnosis, Differential; Disease Progression; fms-Like Tyrosine Kinase 3; Humans; Intracellular Signaling Peptides and Proteins; Multiple System Atrophy; Oncogene Proteins; Parkinson Disease; Peptide Fragments; Phosphorylation; Protein Deglycase DJ-1; ROC Curve; Sensitivity and Specificity; Severity of Illness Index; tau Proteins

Multiple system atrophy is a rapidly progressive neurodegenerative disorder with a markedly reduced life expectancy. Failure of symptomatic treatment raises an urgent need for disease-modifying strategies. We have investigated the neuroprotective potential of erythropoietin in (proteolipid protein)-α-synuclein transgenic mice exposed to 3-nitropropionic acid featuring multiple system atrophy-like pathology including oligodendroglial α-synuclein inclusions and selective neuronal degeneration. Mice were treated with erythropoietin starting before (early erythropoietin) and after (late erythropoietin) intoxication with 3-nitropropionic acid. Nonintoxicated animals receiving erythropoietin and intoxicated animals treated with saline served as control groups. Behavioral tests included pole test, open field activity, and motor behavior scale. Immunohistochemistry for tyrosine hydroxylase and dopamine and cyclic adenosine monophosphate-regulated phosphoprotein (DARPP-32) was analyzed stereologically. Animals receiving erythropoietin before and after 3-nitropropionic acid intoxication scored significantly lower on the motor behavior scale and they performed better in the pole test than controls with no significant difference between early and late erythropoietin administration. Similarly, rearing scores were worse in 3-nitropropionic acid-treated animals with no difference between the erythropoietin subgroups. Immunohistochemistry revealed significant attenuation of 3-nitropropionic acid-induced loss of tyrosine hydroxylase and DARPP-32 positive neurons in substantia nigra pars compacta and striatum, respectively, in both erythropoietin-treated groups without significant group difference in the substantia nigra. However, at striatal level, a significant difference between early and late erythropoietin administration was observed. In the combined (proteolipid protein)-α-synuclein 3-nitropropionic acid multiple system atrophy mouse model, erythropoietin appears to rescue dopaminergic and striatal gabaergic projection neurons. This effect is associated with improved motor function. Further studies are warranted to develop erythropoietin as a potential interventional therapy in multiple system atrophy.

Topics: alpha-Synuclein; Animals; Cell Death; Convulsants; Corpus Striatum; Disease Models, Animal; Dopamine and cAMP-Regulated Phosphoprotein 32; Drug Administration Schedule; Erythropoietin; Exploratory Behavior; Humans; Mice; Mice, Transgenic; Motor Activity; Multiple System Atrophy; Myelin Proteolipid Protein; Nitro Compounds; Propionates; Substantia Nigra; Tyrosine 3-Monooxygenase

Mesenchymal stem cells (MSC) are currently strong candidates for cell-based therapies. They are well known for their differentiation potential and immunoregulatory properties and have been proven to be potentially effective in the treatment of a large variety of diseases, including neurodegenerative disorders. Currently there is no treatment that provides consistent long-term benefits for patients with multiple system atrophy (MSA), a fatal late onset α-synucleinopathy. Principally neuroprotective or regenerative strategies, including cell-based therapies, represent a powerful approach for treating MSA. In this study we investigated the efficacy of intravenously applied MSCs in terms of behavioural improvement, neuroprotection and modulation of neuroinflammation in the (PLP)-αsynuclein (αSYN) MSA model.. MSCs were intravenously applied in aged (PLP)-αSYN transgenic mice. Behavioural analyses, defining fine motor coordination and balance capabilities as well as stride length analysis, were performed to measure behavioural outcome. Neuroprotection was assessed by quantifying TH neurons in the substantia nigra pars compacta (SNc). MSC treatment on neuroinflammation was analysed by cytokine measurements (IL-1α, IL-2, IL-4, IL-5, IL-6, IL-10, IL-17, GM-CSF, INFγ, MCP-1, TGF-β1, TNF-α) in brain lysates together with immunohistochemistry for T-cells and microglia. Four weeks post MSC treatment we observed neuroprotection in the SNc, as well as downregulation of cytokines involved in neuroinflammation. However, there was no behavioural improvement after MSC application.. To our knowledge this is the first experimental approach of MSC treatment in a transgenic MSA mouse model. Our data suggest that intravenously infused MSCs have a potent effect on immunomodulation and neuroprotection. Our data warrant further studies to elucidate the efficacy of systemically administered MSCs in transgenic MSA models.

Topics: alpha-Synuclein; Animals; Behavior, Animal; Brain; Cell Differentiation; Cytokines; Disease Models, Animal; Flow Cytometry; Humans; Immunoenzyme Techniques; Immunomodulation; Mesenchymal Stem Cell Transplantation; Mesenchymal Stem Cells; Mice; Mice, Transgenic; Motor Activity; Multiple System Atrophy; Neurons; Neuroprotective Agents

Glial cytoplasmic inclusions (GCIs) are the pathological hallmarks of multiple system atrophy (MSA) and α-synuclein is abnormally deposited in GCIs. Protein disulfide isomerase (PDI) is a member of the thioredoxin superfamily and is believed to accelerate the folding of disulfide-bonded proteins by catalyzing the disulfide interchange reaction, which is the rate-limiting step during protein folding in the luminal space of the endoplasmic reticulum (ER). Nitric-oxide-induced (NO-induced) S-nitrosylation of PDI inhibits its enzymatic activity, leading to the accumulation of polyubiquitinated proteins, and activates the unfolded protein response in neurodegenerative diseases.. Postmortem brain specimens from five patients with MSA and five normal control brains were utilized in this immunohistochemical study.. We found GCIs positive for anti-PDI antibody in the brain of patients with MSA. In addition, we observed colocalization of α-synuclein and leucine-rich repeat kinase 2 (LRRK2) with PDI in GCIs. As LRRK2 immunoreactivity is associated with one of the earliest oligodendrocytic abnormalities in MSA, colocalization of LRRK2 and PDI in GCIs may be a link to the ER stress of glial cells in the early stages of MSA.. In MSA, NO may inhibit PDI by inducing S-nitrosylation, which inhibits its enzymatic activity and thus allows protein misfolding to occur.

Topics: Aged; alpha-Synuclein; Brain; Humans; Inclusion Bodies; Leucine-Rich Repeat Serine-Threonine Protein Kinase-2; Microscopy, Immunoelectron; Middle Aged; Multiple System Atrophy; Neuroglia; Neurons; Oligodendroglia; Postmortem Changes; Protein Disulfide-Isomerases; Protein Serine-Threonine Kinases

α-synuclein [α-Syn]-mediated activation of GSK-3β leading to increases in hyperphosphorylated Tau has been shown by us to occur in striata of Parkinson's diseased [PD] patients and in animal models of PD. In Alzheimer's disease, tauopathy exists in several brain regions; however, the pattern of distribution of tauopathy in other brain regions of PD or in animal models of PD is not known. The current studies were undertaken to analyze the distribution of tauopathy in different brain regions in a widely used mouse model of PD, the α-Syn overexpressing mouse.. High levels of α-Syn levels were seen in the brain stem, with a much smaller increase in the frontal cortex; neither cerebellum nor hippocampus showed any overexpression of α-Syn. Elevated levels of p-Tau, hyperphosphorylated at Ser202, Ser262 and Ser396/404, were seen in brain stem, with lower levels seen in hippocampus. In both frontal cortex and cerebellum, increases were seen only in p-Ser396/404 Tau, but not in p-Ser202 and p-Ser262. p-GSK-3β levels were not elevated in any of the brain regions, although total GSK-3β was elevated in brain stem. p-p38MAPK levels were unchanged in all brain regions examined, while p-ERK levels were elevated in brain stem, hippocampus and cerebellum, but not the frontal cortex. p-JNK levels were increased in brain stem and cerebellum but not in the frontal cortex or hippocampus. Elevated levels of free tubulin, indicating microtubule destabilization, were seen only in the brain stem.. Our combined data suggest that in this animal model of PD, tauopathy, along with microtubule destabilization, exists primarily in the brain stem and striatum, which are also the two major brain regions known to express high levels of α-Syn and undergo the highest levels of degeneration in human PD. Thus, tauopathy in PD may have a very restricted pattern of distribution.

Topics: alpha-Synuclein; Animals; Brain; Disease Models, Animal; Humans; Mice; Mice, Inbred C57BL; Multiple System Atrophy; Parkinsonian Disorders; Tauopathies; Tissue Distribution; Up-Regulation

The disordered tubulin polymerization promoting protein (TPPP/p25) was found to be co-enriched in neuronal and glial inclusions with α-synuclein in Parkinson disease and multiple system atrophy, respectively; however, co-occurrence of α-synuclein with β-amyloid (Aβ) in human brain inclusions has been recently reported, suggesting the existence of mixed type pathologies that could result in obstacles in the correct diagnosis and treatment. Here we identified TPPP/p25 as an interacting partner of the soluble Aβ oligomers as major risk factors for Alzheimer disease using ProtoArray human protein microarray. The interactions of oligomeric Aβ with proteins involved in the etiology of neurological disorders were characterized by ELISA, surface plasmon resonance, pelleting experiments, and tubulin polymerization assay. We showed that the Aβ(42) tightly bound to TPPP/p25 (K(d) = 85 nm) and caused aberrant protein aggregation by inhibiting the physiologically relevant TPPP/p25-derived microtubule assembly. The pair-wise interactions of Aβ(42), α-synuclein, and tubulin were found to be relatively weak; however, these three components formed soluble ternary complex exclusively in the absence of TPPP/p25. The aggregation-facilitating activity of TPPP/p25 and its interaction with Aβ was monitored by electron microscopy with purified proteins by pelleting experiments with cell-free extracts as well as by confocal microscopy with CHO cells expressing TPPP/p25 or amyloid. The finding that the interaction of TPPP/p25 with Aβ can produce pathological-like aggregates is tightly coupled with unusual pathology of the Alzheimer disease revealed previously; that is, partial co-localization of Aβ and TPPP/p25 in the case of diffuse Lewy body disease with Alzheimer disease.

Topics: alpha-Synuclein; Alzheimer Disease; Amyloid beta-Protein Precursor; Animals; Carrier Proteins; CHO Cells; Cricetinae; Cricetulus; Humans; Lewy Bodies; Multiple System Atrophy; Nerve Tissue Proteins; Parkinson Disease; Protein Array Analysis; Protein Binding; Rats; Rats, Wistar; Tubulin

Multiple system atrophy (MSA) is a sporadic neurodegenerative disorder that encompasses olivopontocerebellar atrophy (OPCA), striatonigral degeneration (SND) and Shy-Drager syndrome (SDS). The histopathological hallmarks are α-synuclein (AS) positive glial cytoplasmic inclusions (GCIs) in oligodendroglias. AS aggregation is also found in glial nuclear inclusions (GNIs), neuronal cytoplasmic inclusions (NCIs), neuronal nuclear inclusions (NNIs) and dystrophic neurties. Reviewing the pathological features of 102 MSA cases, OPCA-type was relatively more frequent and SND-type was less frequent in Japanese MSA cases, which suggested different phenotypic pattern of MSA might exist between races, compared to the relatively high frequency of SND-type in western countries. In early stage of MSA, NNIs, NCIs and diffuse homogenous stain of AS in neuronal nuclei and cytoplasm were observed in various vulnerable lesions including the pontine nuclei, putamen, substantia nigra, locus ceruleus, inferior olivary nucleus, intermediolateral column of thoracic cord, lower motor neurons and cortical pyramidal neurons, in additions to GCIs. These findings indicated that the primary nonfibrillar and fibrillar AS aggregation also occurred in neurons. Therefore both the direct involvement of neurons themselves and the oligodendroglia-myelin-axon mechanism may synergistically accelerate the degenerative process of MSA.

Topics: Aged; Aged, 80 and over; alpha-Synuclein; Female; Histocytochemistry; Humans; Male; Middle Aged; Multiple System Atrophy; Nerve Degeneration; Oligodendroglia

Alpha-synuclein is a major component of Lewy bodies and glial cytoplasmic inclusions, pathological hallmarks of idiopathic Parkinson's disease and multiple system atrophy, and it is assumed to be aetiologically involved in these conditions. However, the quantitative status of brain alpha-synuclein in different Parkinsonian disorders is still unresolved and it is uncertain whether alpha-synuclein accumulation is restricted to regions of pathology. We compared membrane-associated, sodium dodecyl sulfate-soluble alpha-synuclein, both the full-length 17 kDa and high molecular weight species, by western blotting in autopsied brain of patients with Parkinson's disease (brainstem-predominant Lewy body disease: n = 9), multiple system atrophy (n = 11), progressive supranuclear palsy (n = 16), and of normal controls (n = 13). Brain of a patient with familial Parkinsonism-dementia due to alpha-synuclein locus triplication (as positive control) showed increased membrane-associated, sodium dodecyl sulfate-soluble alpha-synuclein levels with abundant high molecular weight immunoreactivity. In multiple system atrophy, a massive increase in 17 kDa membrane-associated, sodium dodecyl sulfate-soluble alpha-synuclein was observed in highly pathologically affected regions, including putamen (+1760%, range +625-2900%), substantia nigra [+1000% (+356-1850%)], and white matter of internal capsule [+2210% (+430-6830%)] together with numerous high molecular weight species. Levels of 17 kDa membrane-associated, sodium dodecyl sulfate-soluble alpha-synuclein were only modestly increased in less affected areas (cerebellar cortex, +95%; caudate, +30%; with both also showing numerous high molecular weight species) and were generally normal in cerebral cortices. In both Parkinson's disease and progressive supranuclear palsy, membrane-associated, sodium dodecyl sulfate-soluble alpha-synuclein levels were normal in putamen and frontal cortex whereas a trend was observed for variably increased 17 kDa membrane-associated, sodium dodecyl sulfate-soluble alpha-synuclein concentrations [+184% (-60% to +618%)] with additional high molecular weight species in Parkinson's disease substantia nigra. No obvious correlation was observed between nigral membrane-associated, sodium dodecyl sulfate-soluble alpha-synuclein accumulation and Lewy body density in Parkinson's disease. Two progressive supranuclear palsy cases had membrane-associated, sodium dodecyl sulfate-soluble alpha-synuclein accumulatio

Topics: Adult; Aged; alpha-Synuclein; Brain; Female; Humans; Male; Middle Aged; Multiple System Atrophy; Parkinson Disease; Supranuclear Palsy, Progressive

Increasing evidence suggests that phosphorylation may play an important role in the oligomerization, fibrillogenesis, Lewy body (LB) formation, and neurotoxicity of alpha-synuclein (alpha-syn) in Parkinson disease. Herein we demonstrate that alpha-syn is phosphorylated at S87 in vivo and within LBs. The levels of S87-P are increased in brains of transgenic (TG) models of synucleinopathies and human brains from Alzheimer disease (AD), LB disease (LBD), and multiple system atrophy (MSA) patients. Using antibodies against phosphorylated alpha-syn (S129-P and S87-P), a significant amount of immunoreactivity was detected in the membrane in the LBD, MSA, and AD cases but not in normal controls. In brain homogenates from diseased human brains and TG animals, the majority of S87-P alpha-syn was detected in the membrane fractions. A battery of biophysical methods were used to dissect the effect of S87 phosphorylation on the structure, aggregation, and membrane-binding properties of monomeric alpha-syn. These studies demonstrated that phosphorylation at S87 expands the structure of alpha-syn, increases its conformational flexibility, and blocks its fibrillization in vitro. Furthermore, phosphorylation at S87, but not S129, results in significant reduction of alpha-syn binding to membranes. Together, our findings provide novel mechanistic insight into the role of phosphorylation at S87 and S129 in the pathogenesis of synucleinopathies and potential roles of phosphorylation in alpha-syn normal biology.

Topics: alpha-Synuclein; Alzheimer Disease; Amino Acid Sequence; Animals; Brain; Cell Membrane; Creatine Kinase; Disease Models, Animal; Humans; Lewy Bodies; Lewy Body Disease; Male; Mice; Mice, Transgenic; Multiple System Atrophy; Neurodegenerative Diseases; Neurons; Parkinson Disease; Phosphorylation; Polymers; Protein Isoforms; Rats; Rats, Wistar; Serine

Multiple systems atrophy (MSA) is a neurodegenerative disorder characterized by oligodendrocytic accumulations of alpha-synuclein (alphasyn). Oxidative stress is a key mechanism proposed to underlie MSA pathology. To address the role of alphasyn modifications, over and above general oxidative modifications, this study examined the effects of 3-nitropropionic acid (3NP) administration, a technique used to model MSA, in knock-out mice lacking alphasyn (alphasynKO). Although susceptible to 3NP-induced oxidative stress, alphasynKO mice display reduced neuronal loss and dendritic pathology. The alphasynKO mice are resistant to 3NP-induced motor deficits and display attenuated loss of tyrosine hydroxylase and dopamine transporter striatal immunoreactivity. The results suggest that deficits in MSA are not due to general oxidative protein modification but in addition may be related to specific alphasyn modifications.

Topics: alpha-Synuclein; Animals; Brain; Disease Models, Animal; Mice; Mice, Knockout; Mice, Transgenic; Multiple System Atrophy; Neurons; Nitro Compounds; Oxidative Stress; Propionates

A retrospective autopsy-based study of the human submandibular gland, one of the three major salivary glands, together with anatomically related peripheral structures (cervical superior ganglion, cervical sympathetic trunk, vagal nerve at the level of the carotid bifurcation), was conducted on a cohort consisting of 33 individuals, including 9 patients with neuropathologically confirmed Parkinson's disease (PD), three individuals with incidental Lewy body disease (iLBD), 2 individuals with neuropathologically confirmed multiple system atrophy (MSA), and 19 controls, using alpha-synuclein immunohistochemistry in 100 mum polyethylene glycol-embedded tissue sections. Lewy pathology (LP) was present in the submandibular glands and cervical superior ganglia in PD (9/9 cases) and iLBD (2/3 cases) but not in MSA or controls. The cervical sympathetic trunk (7/9 PD cases, 2/3 iLBD cases) and peripheral vagal nerves (9/9 PD cases, 2/3 iLBD cases) also displayed LP. The results are discussed within the context of hyposmia as well as autonomic dysfunction in PD (sialorrhea, sialopenia, dysphagia). Potential disease-related changes in salivary volume, contents, and viscosity might make it possible, in combination with other tests, to employ human saliva as a biomarker.

Topics: Aged; Aged, 80 and over; alpha-Synuclein; Cohort Studies; Female; Humans; Immunohistochemistry; Lewy Bodies; Lewy Body Disease; Male; Middle Aged; Multiple System Atrophy; Parkinson Disease; Retrospective Studies; Submandibular Gland; Superior Cervical Ganglion; Vagus Nerve

Topics: alpha-Synuclein; Base Sequence; Brain; DNA Mutational Analysis; Genetic Markers; Genetic Predisposition to Disease; Genetic Testing; Genetic Variation; Homozygote; Humans; Multiple System Atrophy; Odds Ratio; Polymorphism, Single Nucleotide; Regression Analysis; Reproducibility of Results; Risk Factors

The histopathological hallmark of multiple system atrophy is the appearance of intracellular inclusion bodies, named glial cytoplasmic inclusions, which are mainly composed of alpha-synuclein fibrils. In vivo visualization of alpha-synuclein deposition should be used for the diagnosis and assessment of therapy and severity of pathological progression in multiple system atrophy. Because 2-[2-(2-dimethylaminothiazol-5-yl)ethenyl]-6-[2-(fluoro)ethoxy] benzoxazole could stain alpha-synuclein-containing glial cytoplasmic inclusions in post-mortem brains, we compared the carbon-11-labelled 2-[2-(2-dimethylaminothiazol-5-yl)ethenyl]-6-[2-(fluoro)ethoxy] benzoxazole positron emission tomography findings of eight multiple system atrophy cases to those of age-matched normal controls. The positron emission tomography data demonstrated high distribution volumes in the subcortical white matter (uncorrected P < 0.001), putamen and posterior cingulate cortex (uncorrected P < 0.005), globus pallidus, primary motor cortex and anterior cingulate cortex (uncorrected P < 0.01), and substantia nigra (uncorrected P < 0.05) in multiple system atrophy cases compared to the normal controls. They were coincident with glial cytoplasmic inclusion-rich brain areas in multiple system atrophy and thus, carbon-11-labelled 2-[2-(2-dimethylaminothiazol-5-yl)ethenyl]-6-[2-(fluoro)ethoxy] benzoxazole positron emission tomography is a promising surrogate marker for monitoring intracellular alpha-synuclein deposition in living brains.

Topics: alpha-Synuclein; Benzoxazoles; Brain; Carbon Radioisotopes; Female; Humans; Immunohistochemistry; Male; Microscopy, Fluorescence; Middle Aged; Multiple System Atrophy; Positron-Emission Tomography; Thiazoles

Topics: alpha-Synuclein; Genetic Predisposition to Disease; Genetic Variation; Humans; Multiple System Atrophy

Multiple system atrophy (MSA) is a neurodegenerative disorder characterized by striatonigral degeneration and olivo-pontocerebellar atrophy. Neuronal degeneration is accompanied by primarily oligodendrocytic accumulation of alpha-synuclein (alphasyn) as opposed to the neuronal inclusions more commonly found in other alpha-synucleinopathies such as Parkinson's disease. It is unclear how alphasyn accumulation in oligodendrocytes may lead to the extensive neurodegeneration observed in MSA; we hypothesize that the altered expression of oligodendrocyte-derived neurotrophic factors by alphasyn may be involved. In this context, the expression of a number neurotrophic factors reportedly expressed by oligodendrocytes [glial-derived neurotrophic factor (GDNF), brain-derived neurotrophic factor (BDNF), and insulin-like growth factor 1 (IGF-1), as well as basic fibroblast growth factor 2 (bFGF2), reportedly astrocyte derived] were examined in transgenic mouse models expressing human alphasyn (halphasyn) under the control of either neuronal (PDGFbeta or mThy1) or oligodendrocytic (MBP) promoters. Although protein levels of BDNF and IGF-1 were altered in all the alphasyn transgenic mice regardless of promoter type, a specific decrease in GDNF protein expression was observed in the MBP-halphasyn transgenic mice. Intracerebroventricular infusion of GDNF improved behavioral deficits and ameliorated neurodegenerative pathology in the MBP-halphasyn transgenic mice. Consistent with the studies in the MBP-halphasyn transgenic mice, analysis of GDNF expression levels in human MSA samples demonstrated a decrease in the white frontal cortex and to a lesser degree in the cerebellum compared with controls. These results suggest a mechanism in which alphasyn expression in oligodendrocytes impacts on the trophic support provided by these cells for neurons, perhaps contributing to neurodegeneration.

Topics: Aged; alpha-Synuclein; Animals; Behavior, Animal; Brain; Disease Models, Animal; Female; Glial Cell Line-Derived Neurotrophic Factor; Humans; Injections, Intraventricular; Male; Mice; Mice, Knockout; Mice, Transgenic; Multiple System Atrophy; Nerve Degeneration; Nerve Fibers, Myelinated; Nerve Growth Factors; Neurons; Oligodendroglia; Promoter Regions, Genetic

Multiple system atrophy (MSA) is a rare neurodegenerative disease of undetermined cause manifesting with progressive autonomic failure (AF), cerebellar ataxia and parkinsonism due to neuronal loss in multiple brain areas associated with (oligodendro)glial cytoplasmic alpha-synuclein (alpha SYN) inclusions (GCIs). Using proteolipid protein (PLP)-alpha-synuclein (alpha SYN) transgenic mice we have previously reported parkinsonian motor deficits triggered by MSA-like alpha SYN inclusions. We now extend these observations by demonstrating degeneration of brain areas that are closely linked to progressive AF and other non-motor symptoms in MSA, in (PLP)-alpha SYN transgenic mice as compared to age-matched non-transgenic controls. We show delayed loss of cholinergic neurons in nucleus ambiguus at 12 months of age as well as early neuronal loss in laterodorsal tegmental nucleus, pedunculopontine tegmental nucleus and Onuf's nucleus at 2 months of age associated with alpha SYN oligodendroglial overexpression. We also report that neuronal loss triggered by MSA-like alpha SYN inclusions is absent up to 12 months of age in the thoracic intermediolateral cell column suggesting a differential dynamic modulation of alpha SYN toxicity within the murine autonomic nervous system. Although the spatial and temporal evolution of central autonomic pathology in MSA is unknown our findings corroborate the utility of the (PLP)-alpha SYN transgenic mouse model as a testbed for the study of oligodendroglial alpha SYN mediated neurodegeneration replicating both motor and non-motor aspects of MSA.

Topics: alpha-Synuclein; Animals; Brain; Cell Count; Disease Models, Animal; Humans; Mice; Mice, Transgenic; Multiple System Atrophy; Neurons; Oligodendroglia

Multiple system atrophy (MSA) and Parkinson's disease (PD) are classified as synucleinopathies that exhibit α-synuclein deposition in the central nervous system. Recently, activation of the unfolded protein response (UPR), which is a cellular stress response triggered by endoplasmic reticulum (ER) stress, was reported in PD and involvement of ER stress was indicated for this disease. To elucidate whether ER stress is also implicated in the pathology of MSA, we performed a series of immunohistochemical studies using MSA brain sections. Here, we showed the presence of an activated UPR response in oligodendroglia of postmortem MSA brains. The UPR protein-positive structures were observed in lesions where glial cytoplasmic inclusions (GCIs) appeared and colocalized highly in cells showing oligodendrocytic characteristics in the presence of α-synuclein inclusions. The UPR protein-positive structures appeared as granular shapes that are morphologically similar to granulovacuolar degeneration (GVD) and colocalized with GVD marker proteins. Double immunohistochemistry demonstrated that some of the activated UPR protein-positive structures were localized in oligodendrocytes that contained GCIs with faint α-synuclein labeling, without ubiquitination, and showing a strong correlation with the relocation of the tubulin polymerization-promoting protein (TPPP/p25α). These findings suggest that activation of the UPR may be induced at the early stage of the disease process, thus playing a pivotal role in the pathology of MSA.

Topics: Aged; alpha-Synuclein; Brain; DNA-Binding Proteins; eIF-2 Kinase; Endoplasmic Reticulum; Female; Glycogen Synthase Kinase 3; Humans; Male; Microscopy, Electron, Transmission; Middle Aged; Multiple System Atrophy; Nerve Tissue Proteins; Oligodendroglia; Smad2 Protein; tau Proteins; Unfolded Protein Response

Idiopathic REM sleep behavior disorder (RBD) may be the initial manifestation of synucleinopathies (Parkinson disease [PD], multiple system atrophy [MSA], or dementia with Lewy bodies [DLB]).. We used the Mayo medical records linkage system to identify cases presenting from 2002 to 2006 meeting the criteria of idiopathic RBD at onset, plus at least 15 years between RBD and development of other neurodegenerative symptoms. All patients underwent evaluations by specialists in sleep medicine to confirm RBD, and behavioral neurology or movement disorders to confirm the subsequent neurodegenerative syndrome.. Clinical criteria were met by 27 patients who experienced isolated RBD for at least 15 years before evolving into PD, PD dementia (PDD), DLB, or MSA. The interval between RBD and subsequent neurologic syndrome ranged up to 50 years, with the median interval 25 years. At initial presentation, primary motor symptoms occurred in 13 patients: 9 with PD, 3 with PD and mild cognitive impairment (MCI), and 1 with PDD. Primary cognitive symptoms occurred in 13 patients: 10 with probable DLB and 3 with MCI. One patient presented with primary autonomic symptoms, diagnosed as MSA. At most recent follow-up, 63% of patients progressed to develop dementia (PDD or DLB). Concomitant autonomic dysfunction was confirmed in 74% of all patients.. These cases illustrate that the alpha-synuclein pathogenic process may start decades before the first symptoms of PD, DLB, or MSA. A long-duration preclinical phase has important implications for epidemiologic studies and future interventions designed to slow or halt the neurodegenerative process.

Topics: Adult; Aged; Aged, 80 and over; alpha-Synuclein; Female; Follow-Up Studies; Humans; Lewy Body Disease; Longitudinal Studies; Male; Medical Records Systems, Computerized; Middle Aged; Multiple System Atrophy; Parkinson Disease; REM Sleep Behavior Disorder; Retrospective Studies; Time Factors; Young Adult

Multiple system atrophy (MSA) is a progressive neurodegenerative disorder presenting variable combinations of parkinsonism, cerebellar ataxia, corticospinal and autonomic dysfunction. Alpha-synuclein (α-SYN)-immunopositive glial cytoplasmic inclusions (GCIs) represent the neuropathological hallmark of MSA, and tubulin polymerization promoting protein (TPPP)/p25 in oligodendroglia has been known as a potent stimulator of α-SYN aggregation. To gain insight into the molecular pathomechanisms of GCI formation and subsequent oligodendroglial degeneration, we ectopically expressed α-SYN and TPPP in HEK293T and oligodendroglial KG1C cell lines. Here we showed that TPPP specifically accelerated α-SYN oligomer formation and co-immunoprecipitation analysis revealed the specific interaction of TPPP and α-SYN. Moreover, phosphorylation of α-SYN at Ser-129 facilitated the TPPP-mediated α-SYN oligomerization. TPPP facilitated α-SYN-positive cytoplasmic perinuclear inclusions mimicking GCI in both cell lines; however, apoptotic cell death was only observed in KG1C cells. This apoptotic cell death was partly rescued by sirtuin 2 (SIRT2) inhibition. Together, our results provide further insight into the molecular pathogenesis of MSA and potential therapeutic approaches.

Topics: alpha-Synuclein; Apoptosis; Gene Expression Regulation, Enzymologic; Glycogen Synthase Kinase 3; HEK293 Cells; Humans; Multiple System Atrophy; Nerve Tissue Proteins; Oligodendroglia; Phosphorylation; Serine; Sirtuin 2

Multiple system atrophy (MSA) is a neurodegenerative disease caused by an accumulation of alpha-synuclein (alpha-syn) in oligodendrocytes. Little is known about the cellular mechanisms by which alpha-syn accumulation causes neuronal degeneration in MSA. Our previous research, however, revealed that in a mouse model of MSA, oligodendrocytic inclusions of alpha-syn induced neuronal accumulation of alpha-syn, as well as progressive neuronal degeneration. Here we identify the mechanisms that underlie neuronal accumulation of alpha-syn in a mouse MSA model. We found that the alpha-syn protein binds to beta-III tubulin in microtubules to form an insoluble complex. The insoluble alpha-syn complex progressively accumulates in neurons and leads to neuronal dysfunction. Furthermore, we demonstrated that the neuronal accumulation of insoluble alpha-syn is suppressed by treatment with a microtubule depolymerizing agent. The underlying pathological process appeared to also be inhibited by this treatment, providing promise for future therapeutic approaches.

Topics: alpha-Synuclein; Animals; Disease Models, Animal; Fluorescent Antibody Technique; Humans; Immunohistochemistry; Immunoprecipitation; Inclusion Bodies; Mice; Mice, Transgenic; Microtubules; Multiple System Atrophy; Neurons; Oligodendroglia

Topics: Aged, 80 and over; alpha-Synuclein; Cerebellum; Germany; Humans; Immunohistochemistry; Multiple System Atrophy; Neuroglia; Putamen

Multiple system atrophy (MSA) is a progressive neurodegenerative disease characterized by autonomic failure, parkinsonism, cerebellar ataxia, and oligodendrocytic accumulation of alpha-synuclein (alphasyn). Oxidative stress has been linked to neuronal death in MSA and the mitochondrial toxin 3-nitropropionic acid (3NP) is known to enhance the motor deficits and neurodegeneration in transgenic mice models of MSA. However, the effect of 3NP administration on alphasyn itself has not been studied. In this context, we examined the neuropathological effects of 3NP administration in alphasyn transgenic mice expressing human alphasyn (halphasyn) under the control of the myelin basic protein (MBP) promoter and the effect of this administration on posttranslational modifications of alphasyn, on levels of total alphasyn, and on its solubility. We demonstrate that 3NP administration altered levels of nitrated and oxidized alphasyn in the MBP-halphasyn tg while not affecting global levels of phosphorylated or total alphasyn. 3NP administration also exaggerated neurological deficits in the MBP-halphasyn tg mice, resulting in widespread neuronal degeneration and behavioral impairment.

Topics: alpha-Synuclein; Animals; Brain; Convulsants; Disease Models, Animal; Mice; Mice, Transgenic; Mitochondria; Multiple System Atrophy; Myelin Basic Protein; Nerve Degeneration; Nitrates; Nitro Compounds; Oxidative Stress; Promoter Regions, Genetic; Propionates

Multiple system atrophy (MSA), a fatal neurodegenerative disorder, is the second most common cause of parkinsonism and frequently associated with autonomic failure. Previous work from our laboratory has shown that striatal grafts survive and exert functional effects in toxin-induced rodent models of MSA-P, the parkinson variant characterized by levodopa resistance due to loss of striatal medium-sized spiny neurons. It is unknown whether oligodendroglial alpha-synuclein signature lesions affect graft survival in MSA. Recent reports on neurotransplantation in Parkinson's disease patients suggest a possible host-to-graft disease propagation of alpha-synuclein pathology which may be relevant to transplantation in MSA as well. We here demonstrate that embryonic E14 striatal allografts show reduced p-zone volume and dopaminergic graft re-innervation accompanied by increased gliosis in a transgenic MSA mouse model featuring alpha-synuclein oligodendrogliopathy. Oligodendrocytes expressing host-specific alpha-synuclein migrate into the graft tissue after 3 months of survival. Our data suggest that the presence of MSA-like alpha-synuclein oligodendrogliopathy and related to it pro-inflammatory microenvironment may compromise the connectivity and neurorestorative outcome of striatal grafts.

Topics: alpha-Synuclein; Animals; Brain Tissue Transplantation; Corpus Striatum; Disease Models, Animal; Dopamine; Encephalitis; Gliosis; Graft Survival; Growth Cones; Humans; Inclusion Bodies; Mice; Mice, Transgenic; Multiple System Atrophy; Oligodendroglia; Stem Cell Transplantation; Substantia Nigra; Treatment Outcome

To test whether the synucleinopathies Parkinson's disease and multiple system atrophy (MSA) share a common genetic etiology, we performed a candidate single nucleotide polymorphism (SNP) association study of the 384 most associated SNPs in a genome-wide association study of Parkinson's disease in 413 MSA cases and 3,974 control subjects. The 10 most significant SNPs were then replicated in additional 108 MSA cases and 537 controls. SNPs at the SNCA locus were significantly associated with risk for increased risk for the development of MSA (combined p = 5.5 x 10(-12); odds ratio 6.2) [corrected].

Topics: alpha-Synuclein; Female; Gene Frequency; Genetic Predisposition to Disease; Genome-Wide Association Study; Genotype; Humans; Male; Multiple System Atrophy; Odds Ratio; Polymorphism, Single Nucleotide; Risk

Mutations in leucine-rich repeat kinase-2 (LRRK2) are the most common known cause of Parkinson disease, but how this protein results in the pathobiology of Parkinson disease is unknown. Moreover, there is variability in pathology among cases, and alpha-synuclein (alpha-syn) neuronal inclusions are often present, but whether LRRK2 is present in these pathological inclusions is controversial. This study characterizes novel LRRK2 antibodies, some of which preferentially recognize an aggregated form of LRRK2, as observed in cell culture models. Large perinuclear aggregates containing LRRK2 were promoted by proteasome inhibition and prevented by microtubule polymerization inhibition. Furthermore, they were vimentin- and gamma-tubulin- but not lamp1-immunoreactive, suggesting that these structures fit the definition of aggresomes. Inhibition of heat shock protein 90 led to the degradation of only the soluble/cytosolic pool of LRRK2, suggesting that the aggresomes formed independent of the stability provided by the heat shock protein 90. Although these novel anti-LRRK2 antibodies identified aggregates in model cell systems, they did not immunostain pathological inclusions in human brains. Furthermore, coexpression of LRRK2 and alpha-syn did not recruit alpha-syn into aggresomes in cultured cells, even in the presence of proteasome inhibition. Thus, although LRRK2 is a model system for aggresome formation, LRRK2 is not present in alpha-syn pathological inclusions.

Topics: Aged; Aged, 80 and over; alpha-Synuclein; Animals; Antibodies; Brain; Cell Line; Chlorocebus aethiops; COS Cells; Female; HSP90 Heat-Shock Proteins; Humans; Inclusion Bodies; Leucine-Rich Repeat Serine-Threonine Protein Kinase-2; Lewy Body Disease; Male; Middle Aged; Multiple System Atrophy; Neurodegenerative Diseases; Parkinson Disease; Protein Serine-Threonine Kinases

Experimental studies indicate that dopaminergic neurons in the ventral periaqueductal gray matter (PAG) are involved in maintenance of wakefulness. Excessive daytime sleepiness (EDS) is a common manifestation of multiple system atrophy (MSA) and dementia with Lewy bodies (DLB) but involvement of these neurons has not yet been explored.. We sought to determine whether there is loss of dopaminergic neurons in the ventral PAG in MSA and DLB. We studied the midbrain obtained at autopsy from 12 patients (9 male, 3 female, age 61 +/- 3) with neuropathologically confirmed MSA, 12 patients (11 male, 1 female, age 79 +/- 4) with diagnosis of DLB and limbic or neocortical Lewy body disease, and 12 controls (7 male, 5 female, ages 67 +/- 4). Fifty-micron sections were immunostained for tyrosine hydroxylase (TH) or alpha-synuclein and costained with thionin. Cell counts were performed every 400 mum throughout the ventral PAG using stereologic techniques.. Compared to the total estimated cell numbers in controls (21,488 +/- 8,324 cells), there was marked loss of TH neurons in the ventral PAG in both MSA (11,727 +/- 5,984; p < 0.01) and DLB (5,163 +/- 1,926; p < 0.001) cases. Cell loss was more marked in DLB than in MSA. There were characteristic alpha-synuclein inclusions in the ventral PAG in both MSA and DLB.. There is loss of putative wake-active ventral periaqueductal gray matter dopaminergic neurons in both multiple system atrophy and dementia with Lewy bodies, which may contribute to excessive daytime sleepiness in these conditions.

Topics: Aged; Aged, 80 and over; alpha-Synuclein; Cell Count; Cell Death; Dopamine; Female; Humans; Inclusion Bodies; Lewy Body Disease; Male; Mesencephalon; Middle Aged; Multiple System Atrophy; Neurons; Periaqueductal Gray; Thionins; Tyrosine 3-Monooxygenase

Progressive supranuclear palsy (PSP) and multiple system atrophy (MSA) are both rare neurodegenerative diseases. In the Queen Square Brain Bank, from 2001 to 2008, we received 120 cases of pathologically confirmed PSP and 36 of MSA, and one had concomitant PSP and MSA pathology. The clinical symptoms in this case were compatible with PSP and did not predict the dual pathology. The growing number of collective case reports, including the one reported here, might suggest an increased prevalence of concomitant PSP and MSA than what would be expected by chance.

Topics: Aged; alpha-Synuclein; Astrocytes; Biomarkers; Brain; Comorbidity; Disease Progression; Female; Humans; Immunohistochemistry; Inclusion Bodies; Mass Screening; Multiple System Atrophy; Neural Pathways; Neurons; Oligodendroglia; Parkinson Disease; Prevalence; Severity of Illness Index; Supranuclear Palsy, Progressive; tau Proteins

The reactive changes in different types of astrocytes were analyzed in parkinsonian syndromes in order to identify common reactions and their relationship to disease severity. Immunohistochemistry was used on formalin-fixed, paraffin-embedded sections from the putamen, pons, and substantia nigra from 13 Parkinson disease (PD), 29 multiple-system atrophy (MSA), 34 progressive supranuclear palsy (PSP), 10 corticobasal degeneration(CBD), and 13 control cases. Classic reactive astrocytes were observed in MSA, PSP, and CBD, but not PD cases; the extent of reactivity correlated with indices of neurodegeneration and disease stage. Approximately 40% to 45% of subcortical astrocytes in PD and PSP accumulated alpha-synuclein and phospho-tau, respectively; subcortical astrocytes in MSA and CBD cases did not accumulate these proteins. Protoplasmic astrocytes were identified from fibrous astrocytes by their expression of parkin coregulated gene and apolipoprotein D, and accumulated abnormal proteins in PD, PSP, and CBD, but not MSA. The increased reactivity of parkin coregulated gene-immunoreactive protoplasmic astrocytes correlated with parkin expression in PSP and CBD. Nonreactive protoplasmic astrocytes were observed in PD and MSA cases; in PD, they accumulated alpha-synuclein, suggesting that the attenuated response might be due to an increase in the level of alpha-synuclein. These heterogeneous astroglial responses in PD, MSA, PSP, and CBD indicate distinct underlying pathogenic mechanisms in each disorder.

Topics: alpha-Synuclein; Apolipoproteins D; Astrocytes; Glycoproteins; Humans; Immunohistochemistry; Membrane Transport Proteins; Multiple System Atrophy; Nerve Degeneration; Parkinson Disease; Parkinsonian Disorders; Phosphorylation; Pons; Putamen; Severity of Illness Index; Substantia Nigra; Supranuclear Palsy, Progressive; tau Proteins

In this study, we used immunohistochemistry to screen for alpha-synuclein pathology in the brains of 241 individuals without clinical evidence of neurologic disease, and discovered 36 cases (15%) with incidental Lewy bodies (LBs) and one case, a 96-year-old woman (0.4%), with inclusions similar to those seen in multiple system atrophy (MSA), a non-familial neurodegenerative disorder characterized by parkinsonism, cerebellar ataxia and autonomic dysfunction and alpha-synuclein immunoreactive glial cytoplasmic inclusions (GCI). In a routine hospital autopsy series of 125 brains, we detected GCI in a neurologically normal 82-year-old man (0.8%). Both cases showed widespread GCI in the central nervous system, as well as a few neuronal cytoplasmic inclusions, but no neuronal loss or gliosis in vulnerable brain regions, including the substantia nigra, putamen, inferior olive and pontine base. Applying a recently proposed grading scale for MSA, the two cases showed pathology far below that detected in patients with clinically overt MSA, suggesting the possibility that these two individuals had preclinical MSA. The prevalence of clinically overt MSA is estimated to be about 4 per 100,000 persons (0.004%), which is far less than the frequency of GCI in this series (0.4-0.8%). Further studies are needed to determine if GCI in neurologically normal elderly represents prodromal MSA or a rare non-progressive age-related alpha-synucleinopathy.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; alpha-Synuclein; Female; Humans; Immunoenzyme Techniques; Inclusion Bodies; Lewy Bodies; Male; Middle Aged; Multiple System Atrophy; Neuroglia

Multiple system atrophy (MSA) is a progressive neurodegenerative disorder characterized by oligodendrocytic cytoplasmic inclusions containing abnormally aggregated alpha-synuclein. This aggregation has been linked to the neurodegeneration observed in MSA. Current MSA treatments are aimed at controlling symptoms rather than tackling the underlying cause of neurodegeneration. This study investigates the ability of the antibiotic rifampicin to reduce alpha-synuclein aggregation and the associated neurodegeneration in a transgenic mouse model of MSA. We report a reduction in monomeric and oligomeric alpha-synuclein and a reduction in phosphorylated alpha-synuclein (S129) upon rifampicin treatment. This reduction in alpha-synuclein aggregation was accompanied by reduced neurodegeneration. On the basis of its anti-aggregenic properties, we conclude that rifampicin may have therapeutic potential for MSA.

Topics: alpha-Synuclein; Animals; Antibiotics, Antitubercular; beta-Synuclein; Blotting, Western; Disease Models, Animal; Humans; Immunohistochemistry; Inclusion Bodies; Injections, Intraperitoneal; Mice; Mice, Transgenic; Microscopy, Confocal; Multiple System Atrophy; Nerve Degeneration; Oligodendroglia; Rifampin; Synucleins

A consensus conference on multiple system atrophy (MSA) in 1998 established criteria for diagnosis that have been accepted widely. Since then, clinical, laboratory, neuropathologic, and imaging studies have advanced the field, requiring a fresh evaluation of diagnostic criteria. We held a second consensus conference in 2007 and present the results here.. Experts in the clinical, neuropathologic, and imaging aspects of MSA were invited to participate in a 2-day consensus conference. Participants were divided into five groups, consisting of specialists in the parkinsonian, cerebellar, autonomic, neuropathologic, and imaging aspects of the disorder. Each group independently wrote diagnostic criteria for its area of expertise in advance of the meeting. These criteria were discussed and reconciled during the meeting using consensus methodology.. The new criteria retain the diagnostic categories of MSA with predominant parkinsonism and MSA with predominant cerebellar ataxia to designate the predominant motor features and also retain the designations of definite, probable, and possible MSA. Definite MSA requires neuropathologic demonstration of CNS alpha-synuclein-positive glial cytoplasmic inclusions with neurodegenerative changes in striatonigral or olivopontocerebellar structures. Probable MSA requires a sporadic, progressive adult-onset disorder including rigorously defined autonomic failure and poorly levodopa-responsive parkinsonism or cerebellar ataxia. Possible MSA requires a sporadic, progressive adult-onset disease including parkinsonism or cerebellar ataxia and at least one feature suggesting autonomic dysfunction plus one other feature that may be a clinical or a neuroimaging abnormality.. These new criteria have simplified the previous criteria, have incorporated current knowledge, and are expected to enhance future assessments of the disease.

Topics: alpha-Synuclein; Autonomic Nervous System Diseases; Basal Ganglia; Brain; Cerebellar Ataxia; Cerebellum; Diagnosis, Differential; Inclusion Bodies; Multiple System Atrophy; Parkinsonian Disorders

HtrA2/Omi is a mitochondrial serine protease that is released into the cytosol and promotes apoptotic processes by binding to several members of the inhibitors of apoptosis protein family. HtrA2/Omi knockout mice show a parkinsonian phenotype, and mutations in the gene encoding HtrA2/Omi have been identified as susceptibility factors for Parkinson disease (PD). These results suggest that HtrA2/Omi may be involved in the pathogenesis of PD. We performed immunohistochemical studies of HtrA2/Omi on brains from patients with alpha-synuclein-related disorders, including PD, dementia with Lewy bodies (DLB), and multiple-system atrophy (MSA); patients with other neurodegenerative diseases; and controls. HtrA2/Omi is expressed in normal brain tissue, and there was some anti-HtrA2/Omi immunostaining of neurons in normal brains as well as those with other neurodegenerative diseases. In PD and DLB brains, both classic (i.e. brainstem-type) and cortical Lewy bodies were intensely immunostained; pale bodies were also strongly immunopositive for HtrA2/Omi. In MSA brains, numerous glial cytoplasmic inclusions, neuronal cytoplasmic inclusions, and dystrophic neurites were also intensely immunoreactive for HtrA2/Omi. These results suggest that widespread accumulation of HtrA2/Omi may occur in pathologic alpha-synuclein-containing inclusions in brains with PD, DLB, or MSA and that HtrA2/Omi may be associated with the pathogenesis of alpha-synucleinopathies.

Topics: Aged; Aged, 80 and over; alpha-Synuclein; Animals; Autopsy; Blotting, Western; Brain; Brain Chemistry; Female; Fluorescent Antibody Technique, Indirect; High-Temperature Requirement A Serine Peptidase 2; Humans; Immunohistochemistry; Inclusion Bodies; Lewy Bodies; Lewy Body Disease; Male; Mice; Mice, Knockout; Middle Aged; Mitochondrial Proteins; Multiple System Atrophy; Nervous System Diseases; Neuroglia; Neurons; Parkinson Disease; Serine Endopeptidases

Certain genetic defects in LRRK2 and parkin are pathogenic for Parkinson's disease (PD) and both proteins deposit in the characteristic Lewy bodies. LRRK2 is thought to be involved in the early initiation of Lewy bodies. The involvement of LRRK2 and parkin in the similar cellular deposition of fibrillar alpha-synuclein in glial cytoplasmic inclusions (GCI) in multiple system atrophy (MSA) has not yet been assessed. To determine whether LRRK2 and parkin may be similarly associated with the abnormal deposition of alpha-synuclein in MSA GCI, paraffin-embedded sections from the basal ganglia of 12 patients with MSA, 4 with PD and 4 controls were immunostained for LRRK2, parkin, alpha-synuclein and oligodendroglial proteins using triple labelling procedures. The severity of neuronal loss was graded and the proportion of abnormally enlarged oligodendroglia containing different combinations of proteins assessed in 80-100 cells per case. Parkin immunoreactivity was observed in only a small proportion of GCI. In contrast, LRRK2 was found in most of the enlarged oligodendroglia in MSA and colocalised with the majority of alpha-synuclein-immunopositive GCI. Degrading myelin sheaths containing LRRK2-immunoreactivity were also observed, showing an association with one of the earliest oligodendroglial abnormalities observed in MSA. The proportion of LRRK2-immunopositive GCI was negatively associated with an increase in neuronal loss and alpha-synuclein-immunopositive dystrophic axons. Our results indicate that an increase in LRRK2 expression occurs early in association with myelin degradation and GCI formation, and that a reduction in LRRK2 expression in oligodendroglia is associated with increased neuronal loss in MSA.

Topics: Aged; alpha-Synuclein; Axons; Basal Ganglia; Female; Fluorescent Antibody Technique; Humans; Immunohistochemistry; Inclusion Bodies; Internal Capsule; Leucine-Rich Repeat Serine-Threonine Protein Kinase-2; Male; Middle Aged; Multiple System Atrophy; Myelin Sheath; Nerve Degeneration; Parkinson Disease; Protein Serine-Threonine Kinases; Putamen; Ubiquitin; Ubiquitin-Protein Ligases

Multiple system atrophy (MSA) is a sporadic neurodegenerative disease manifested clinically by progressive ataxia, parkinsonism, and autonomic dysfunction. Its cause is unknown, and there is no curative therapy. Alpha-synuclein is an important protein forming aggregations called glial cytoplasmic inclusions (GCIs) in oligodendroglia; these aggregations are considered important in MSA pathogenesis. Overexpression of the human alpha-synuclein gene in mice induces the formation of GCI-like aggregations in oligodendrocytes, leading mice to exhibit neurological signs similar to those in MSA patients. However, previous studies have excluded mutations within the coding region of the alpha-synuclein gene in MSA patients. To determine whether alteration in the expression level of the alpha-synuclein gene is associated with MSA pathogenesis, we used TaqMan quantitative PCR assay to analyze the alpha-synuclein gene copy number in patients' genomes. We also used quantitative RT-PCR and in situ hybridization to analyze alpha-synuclein mRNA expression in MSA patients' brain tissues. We found no alteration in the alpha-synuclein gene copy number in the patients' genomes (n = 50). Quantitative analysis for alpha-synuclein mRNA by the TaqMan method showed that alpha-synuclein mRNA levels were comparable between control (n = 3) and MSA (n = 3) cerebella. On in situ hybridization, the number of neurons with alpha-synuclein mRNA expression was no greater in the cerebella of MSA patients (n = 3) than in the controls (n = 3). However, GCIs were seen in these MSA specimens on immunohistochemistry for alpha-synuclein. These results suggest that alpha-synuclein gene expression is not the fundamental cause of MSA.

Topics: alpha-Synuclein; Case-Control Studies; Cerebellum; Core Binding Factor beta Subunit; Female; Gene Dosage; Gene Expression; Humans; Immunoenzyme Techniques; In Situ Hybridization; Inclusion Bodies; Male; Middle Aged; Multiple System Atrophy; Oligodendroglia; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger

alpha-Synuclein gene (SNCA) multiplication was found in familial Parkinson disease (PD). We examined SNCA multiplication in patients with familial and sporadic PD and multiple system atrophy (MSA).. We screened 1,106 patients with parkinsonism (PD = 906, MSA = 200) for SNCA multiplication by multiplex PCR. Fluorescent in situ hybridization was done to confirm the multiplication. [(123)I]N-omega-Fluoropropyl-2 beta-carbomethoxy-3beta-(4-iodophenyl)-tropane ([(123)I]FP-CIT) SPECT was done in the patients with SNCA multiplication and their family members.. Three patients were identified as having SNCA duplication. One patient had a positive family history, and two patients were sporadic. Each patient had asymptomatic carriers in their families. The familial case had early onset parkinsonism with rapidly progressive course, cognitive impairment, and dysautonomia. Sporadic cases were more typical of PD. [(123)I]FP-CIT SPECT was abnormal in the patients and normal in the asymptomatic carriers.. SNCA multiplication is present in sporadic Parkinson disease (PD) and needs to be screened. Low penetrance, clinical heterogeneity, and normal dopamine transporter imaging in asymptomatic carriers may suggest the presence of other genetic modifiers or environmental triggers that play a role in the pathogenesis of PD due to SNCA duplication.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; alpha-Synuclein; Child; DNA Mutational Analysis; Exons; Family Health; Female; Humans; In Situ Hybridization, Fluorescence; Iodine Radioisotopes; Male; Middle Aged; Multiple System Atrophy; Mutation; Parkinson Disease; Tomography, Emission-Computed, Single-Photon; Tropanes

Topics: alpha-Synuclein; Atrophy; Brain; Fatal Outcome; Follow-Up Studies; Humans; Lewy Bodies; Magnetic Resonance Imaging; Male; Middle Aged; Multiple System Atrophy; Parkinson Disease; Pneumonia, Aspiration; Spinal Cord; Urinary Bladder, Neurogenic

Degeneration of the cardiac sympathetic nerve occurs in both Parkinson's disease (PD) and dementia with Lewy bodies and begins early in the disease progression of PD, accounting for reduced cardiac uptake of meta-iodobenzylguanidine even in the early stages of Lewy body disease (LBD). We previously demonstrated that degeneration of the distal axons of the cardiac sympathetic nerve precedes loss of their mother neurons in the paravertebral sympathetic ganglia, suggesting distal dominant degeneration of the cardiac sympathetic nerve in PD. Because alpha-synuclein is one of the key molecules in the pathogenesis of this disease, we further investigated how alpha-synuclein aggregates are involved in this distal-dominant degeneration. Both cardiac tissues and paravertebral sympathetic ganglia were obtained for comparison from 20 patients with incidental Lewy body disease (ILBD), 10 with PD, 20 with multiple system atrophy (MSA) and 10 control subjects. Immunohistochemical analysis was performed using antibodies against tyrosine hydroxylase (TH) as a marker for sympathetic nerves, phosphorylated neurofilament as a marker for axons and phosphorylated alpha-synuclein for pathological deposits. We found that (i) alpha-synuclein aggregates in the epicardial nerve fascicles, namely the distal axons of the cardiac sympathetic nerve, were much more abundant in ILBD with preserved TH-ir axons than in this disease with decreased TH-ir axons and PD; (ii) alpha-synuclein aggregates in the epicardial nerve fascicles were closely related to the disappearance of TH-ir axons; (iii) in ILBD with preserved TH-ir axons, alpha-synuclein aggregates were consistently more abundant in the epicardial nerve fascicles than in the paravertebral sympathetic ganglia; (iv) this distal-dominant accumulation of alpha-synuclein aggregates was reversed in ILBD with decreased TH-ir axons and PD, which both showed fewer of these axons but more abundant alpha-synuclein aggregates in the paravertebral sympathetic ganglia and (v) MSA was completely different from ILBD and PD based on the preservation of TH-ir axons and the scarcity of alpha-synuclein aggregates in either the cardiac tissues or the paravertebral sympathetic ganglia. These findings indicate that accumulation of alpha-synuclein aggregates in the distal axons of the cardiac sympathetic nervous system precedes that of neuronal somata or neurites in the paravertebral sympathetic ganglia and that heralds centripetal degeneration of the car

Topics: Aged; Aged, 80 and over; alpha-Synuclein; Axons; Female; Ganglia, Sympathetic; Heart; Humans; Lewy Body Disease; Male; Middle Aged; Multiple System Atrophy; Nerve Degeneration; Parkinson Disease; Pericardium; Sympathetic Nervous System; Tyrosine 3-Monooxygenase

Rasagiline is a novel selective irreversible monoamine oxidase-B (MAO-B) inhibitor recently introduced for the symptomatic treatment of Parkinson disease. Like other propargylamines rasagiline has also shown neuroprotective effects independent of MAO-B-inhibition in various in vitro and in vivo models. The present study was performed to test the potential of rasagiline as a disease-modifying agent in multiple system atrophy (MSA) using a transgenic mouse model previously described by our group. (PLP)-alpha-synuclein transgenic mice featuring glial cytoplasmic inclusion pathology underwent 3-nitropropionic acid intoxication to model full-blown MSA-like neurodegeneration. Two doses of rasagiline were used (0.8 and 2.5 mg/kg) for a treatment period of 4 weeks. Rasagiline-treated animals were compared to placebo saline-treated mice by evaluation of motor behaviour and neuropathology. Motor behavioural tests including pole test, stride length test and general motor score evaluation showed improvements in motor deficits associated with 2.5 mg/kg rasagiline therapy. Immunohistochemistry and histology showed significant reduction of 3-NP-induced neuronal loss in striatum, substantia nigra pars compacta, cerebellar cortex, pontine nuclei and inferior olives of MSA mice receiving 2.5 mg/kg rasagiline. The results of the study indicate that rasagiline confers neuroprotection in a transgenic mouse model of MSA and may therefore be considered a promising disease-modifying candidate for human MSA.

Topics: alpha-Synuclein; Analysis of Variance; Animals; Behavior, Animal; Brain; Disease Models, Animal; Dopamine and cAMP-Regulated Phosphoprotein 32; Dose-Response Relationship, Drug; Indans; Mice; Mice, Transgenic; Motor Activity; Multiple System Atrophy; Myelin Proteolipid Protein; Neurons; Neuroprotective Agents; Nitro Compounds; Propionates; Psychomotor Performance; Tyrosine 3-Monooxygenase

The A5 noradrenergic group of the pons projects on the medulla and spinal cord and contributes to control of sympathetic activity and respiration. Because these functions are affected in multiple system atrophy (MSA), we sought to determine whether there was involvement of A5 neurons in this disorder. We counted tyrosine-hydroxylase (TH) immunoreactive neurons in the A5 area and locus ceruleus in the pons obtained from six patients with clinical and neuropathological diagnoses of MSA and six age-matched controls using stereological methods. There was a severe loss of A5 neurons in MSA (total cell number 3,215 +/- 258 in controls and 321 +/- 62 in MSA, P < 0.001). The severity of cell loss was comparable to that of locus ceruleus neurons in these cases. Our results indicate that A5 neurons are severely affected in MSA and this may contribute to some of the manifestations of this synucleinopathy.

Topics: Aged; Aged, 80 and over; alpha-Synuclein; Analysis of Variance; Case-Control Studies; Cell Count; Cell Death; Female; Humans; Locus Coeruleus; Male; Middle Aged; Multiple System Atrophy; Neurons; Tyrosine 3-Monooxygenase

Alpha-synuclein, parkin, and synphilin-1 are proteins mainly involved in the pathogenesis of Lewy body (LB) diseases. mRNAs of all three undergo alternative splicing, so that the existence of various isoforms has been described. Since increasing evidence supports the importance of differential isoform-expression changes in disease development, we have established isoform-expression profiles in frontal cortices of LB disease brains in comparison with those of Alzheimer disease (AD) and control frontal cortices. The differential expression of four alpha-synuclein, seven parkin, and four synphilin-1 isoforms was ascertained by the use of isoform-specific primers and relative expression analysis with SybrGreen and beta-actin as an internal standard. The establishment of isoform-expression profiles revealed that these are disease specific. Moreover, isoform-expression deregulation of mainly one gene in each disease could be observed. All four alpha-synuclein isoforms were affected in the case of the pure form of dementia with LB, most parkin transcript variants in common LB disease, and all synphilin-1 isoforms in Parkinson disease. Only minor involvement was detected in AD. Finally, the existence of a proprietary isoform-expression profile in common LB disease indicates that this disease develops as a result of its own molecular mechanisms, and so, at the molecular level, it does not exactly share changes found in pure dementia with LB and AD. In conclusion, isoform-expression profiles in LB diseases represent additional evidence for the direct involvement of isoform-expression deregulation in the development of neurodegenerative disorders.

Topics: Aged; Aged, 80 and over; alpha-Synuclein; Alzheimer Disease; Base Sequence; Carrier Proteins; Case-Control Studies; DNA Primers; Female; Frontal Lobe; Gene Expression; Gene Expression Profiling; Humans; Lewy Body Disease; Male; Middle Aged; Multiple System Atrophy; Nerve Tissue Proteins; Parkinson Disease; Polymerase Chain Reaction; Protein Isoforms; RNA, Messenger; Ubiquitin-Protein Ligases

In multiple system atrophy (MSA), it has been accepted that the motor-related cortical area may degenerate. However, there have been few investigations of the postcentral cortex of the somatosensory area. For this reason, we investigated the effects of MSA on both the precentral and the postcentral cortex and were able to demonstrate degenerative changes in each. Furthermore, our study showed that degeneration of the postcentral cortex preceded that of the precentral cortex. In addition, we showed that the Betz cells were not selectively lost, but merely depleted like other neurons of the deep cortical layers. Therefore, the effects of MSA are apparently related to selective loss of the small-sized myelinated fibers in the corticospinal tract.

Topics: alpha-Synuclein; Antigens, CD; Antigens, Differentiation, Myelomonocytic; Female; Glial Fibrillary Acidic Protein; Humans; Male; Middle Aged; Multiple System Atrophy; Nerve Degeneration; Somatosensory Cortex; Statistics, Nonparametric

The cerebellar variant of multiple system atrophy (MSA-C) has overlapping clinical features with the hereditary spinocerebellar ataxias (SCAs), but can usually be distinguished on a clinical basis. We describe a patient who developed a sporadic, late-onset, rapidly progressive neurodegenerative disorder consistent with MSA-C. Genetic testing, however, showed an abnormal expansion of one allele of the spinocerebellar ataxia 3 (SCA3) gene. The clinical impression of MSA-C was confirmed by identification of numerous alpha-synuclein-containing glial cytoplasmic inclusions on autopsy. These findings suggest that abnormal expansion of the SCA3 gene may be a risk factor for the development of MSA-C.

Topics: Alleles; alpha-Synuclein; Ataxin-3; Autopsy; Cerebellum; DNA Repeat Expansion; Fatal Outcome; Female; Humans; Inclusion Bodies; Middle Aged; Multiple System Atrophy; Myelin Sheath; Nerve Degeneration; Nerve Tissue Proteins; Neuroglia; Nuclear Proteins; Point Mutation; Putamen; Repressor Proteins; Severity of Illness Index; Spinocerebellar Ataxias

Topics: alpha-Synuclein; Brain Diseases; Humans; Inclusion Bodies; Lewy Bodies; Lewy Body Disease; Multiple System Atrophy; Neurodegenerative Diseases; Neuroglia; Parkinson Disease; Protein Kinases

Multiple system atrophy (MSA) is a disorder that may manifest with reduced respiratory chemosensitivity and central sleep apnoea. Chemosensitive glutamatergic and serotonergic neurons located just beneath the ventral medullary surface, corresponding to the human arcuate nucleus (ArcN), have recently been implicated in control of automatic breathing in response to hypercapnia and hypoxia. We sought to determine whether these neurons were affected in MSA. Medullae were obtained at post-mortem from 11 patients (8 men, 3 women, age 64 +/- 3 years) with neuropathologically confirmed MSA and 11 control subjects (6 men and 5 women, age 66 +/- 4 years). Fifty micrometre sections obtained throughout the medulla were processed for vesicular glutamate transporter-2 (VGLUT-2), tryptophan-hydroxylase (TrOH), glial fibrillary acid protein (GFAP) and alpha-synuclein immunoreactivity. Cell counts, GFAP immunoreactivity and presence of glial cytoplasmic inclusions (GCIs) were assessed in the ArcN. In MSA, compared with controls, there was a marked depletion of ArcN neurons immunoreactive for either VGLUT-2 (74 +/- 21 versus 342 +/- 84 cells/section, P < 0.004) or TrOH (5 +/- 1 versus 16 +/- 2 cells/section, P < 0.001). There was also marked astrocytic gliosis and accumulation of alpha-synuclein immunoreactive GCIs in the ventral medullary surface in all cases. Our results indicate that there is severe loss of putative chemosensitive glutamatergic and serotonergic neurons as well as marked astrocytic gliosis in the ventral medullary surface in MSA. This may provide a possible morphological basis for impaired respiratory chemosensitivity and central sleep apnoea in this disorder.

Topics: Adult; Aged; Aged, 80 and over; alpha-Synuclein; Arcuate Nucleus of Hypothalamus; Female; Glial Fibrillary Acidic Protein; Gliosis; Humans; Male; Medulla Oblongata; Middle Aged; Multiple System Atrophy; Neurons; Respiratory Mechanics; Sleep Apnea, Obstructive; Tryptophan Hydroxylase; Vesicular Glutamate Transport Protein 2

Recent studies have shown the co-existence of alpha-synuclein and phosphorylated tau (pTau) in several neurodegenerative diseases. Here, we report two autopsy cases of combined multiple system atrophy (MSA) and Alzheimer's disease (AD). In both cases, abundant alpha-synuclein-positive glial and neuronal cytoplasmic inclusions were found in the brainstem, amygdala and hippocampal formation. pTau-positive neurofibrillary tangles (NFTs) were widely distributed in case 1 (Braak stage VI) and moderate in case 2 (Braak stage III). Although alpha-synuclein and pTau pathology co-occurred in the hippocampus and entorhinal cortex, only a few neurons showed co-existence of these two proteins. Immunoreactivity for p62, a ubiquitin proteasome system related protein, was found in the majority of NFTs, but in only a small proportion of neuronal alpha-synuclein inclusions. In addition, UBB+1, a mutant form of ubiquitin and a marker for proteasomal dysfunction, was present in the majority of NFTs, whereas co-existence of alpha-synuclein and UBB+1 was found in only a few neurons. These findings indicate that alpha-synuclein and phosphorylated tau co-occur in certain brain regions in cases of combined MSA and AD and that the proteasomal pathways differ between alpha-synuclein- and pTau-bearing neurons.

Topics: Adaptor Proteins, Signal Transducing; Aged; alpha-Synuclein; Alzheimer Disease; Humans; Male; Multiple System Atrophy; Neurofibrillary Tangles; Sequestosome-1 Protein; tau Proteins; Ubiquitin

Topics: alpha-Synuclein; Cognition Disorders; Female; Fluorescent Antibody Technique; Humans; Immunohistochemistry; Lewy Body Disease; Microscopy, Confocal; Microscopy, Electron; Middle Aged; Multiple System Atrophy

Heat shock proteins (HSPs) are molecular chaperones which can be induced by several kinds of stresses, and Hsc70 and Hsp70 are two major members of the family of 70 kDa HSPs. A major component of Lewy bodies (LBs) is alpha-synuclein, and Hsp70 has been observed in the LBs of brains with Parkinson's disease. Hsp70 has also been demonstrated to have the ability to suppress alpha-synuclein toxicity in vitro and in vivo. To investigate the precise role of Hsc70 and Hsp70 in patients with multiple system atrophy (MSA), which is another alpha-synuclein-related disease, we performed immunohistochemical studies on Hsc70 and Hsp70 using autopsied brains from 7 normal subjects and 15 patients with MSA. In the normal human brains, both neurons and glial cells, including oligodendrocytes, showed only weak Hsc70 and Hsp70 immunoreactivities. In contrast, in the brains with MSA, numerous glial cytoplasmic inclusions (GCIs) were intensely immunostained with Hsc70, and strong Hsc70 immunoreactivity was also found in glial intranuclear inclusions (GNIs), neuronal cytoplasmic inclusions (NCIs) and neuronal intranuclear inclusions (NNIs) as well as dystrophic neurites. The immunolabeling pattern for Hsp70 in the MSA brains was slightly different from that of Hsc70, and Hsp70 immunoreactivity was observed in many reactive astrocytes as well as some glial and neuronal inclusions. Our results suggest that the widespread accumulation of Hsc70 and Hsp70 may occur in brains with MSA, and that Hsc70 and Hsp70 may be associated with the pathogenesis of MSA.

Topics: Aged; alpha-Synuclein; Autopsy; Blotting, Western; Cytoplasm; Female; HSP70 Heat-Shock Proteins; Humans; Inclusion Bodies; Male; Middle Aged; Multiple System Atrophy; Neuroglia; Transferrin

Multiple system atrophy (MSA) is a neurodegenerative disease characterized by various degrees of Parkinsonism, cerebellar ataxia, and autonomic dysfunction. In this report, Affymetrix DNA microarrays were used to measure changes in gene expression in the rostral pons, an area that undergoes extensive damage in MSA, but not other synucleinopathies. Significant changes in expression of 254 genes (180 downregulated and 74 upregulated) occurred in pons tissue from MSA patients when compared with control patients. The downregulated genes were primarily associated with biological functions known to be impaired in Parkinson's disease (PD) and other neurological diseases; for example, downregulation occurred in genes associated with mitochondrial function, ubiquitin-proteasome function, protein modification, glycolysis/metabolism, and ion transport. On the other hand, upregulated genes were associated with transcription/RNA modification, inflammation, immune system function, and oligodendrocyte maintenance and function. Immunocytochemistry, in conjunction with quantitative image analysis, was carried out to characterize alpha-synuclein protein expression as glial cytoplasmic inclusions in the pontocerebellar tract in rostral pons tissue and to determine the relationship between the amount of aggregated alpha-synuclein protein and changes in specific gene expression. Of the regulated genes, 86 were associated with the amount of observed aggregated alpha-synuclein protein in the rostral pons tissue. These data indicate that cells in the pons of MSA patients show changes in gene expression previously associated with the substantia nigra of PD patients and/or other neurological diseases, with additional changes, for example related to oligodendrocyte function unique to MSA.

Topics: alpha-Synuclein; Brain; Cadaver; Gene Expression Regulation; Humans; Immunohistochemistry; Multiple System Atrophy; Oligonucleotide Array Sequence Analysis; Postmortem Changes; Reference Values; Reverse Transcriptase Polymerase Chain Reaction; RNA

Multiple system atrophy (MSA) is by nature a 'sporadic' disease with no evidence of familial aggregation observed. However, the alpha-synuclein locus (SNCA) multiplication families have clinically displayed parkinsonism and autonomic dysfunction. The present study did not find any SNCA multiplications in a series of 58 pathologically confirmed MSA cases excluding this event as a common cause of MSA. The question of a genetic component in MSA remains to be answered.

Topics: alpha-Synuclein; DNA Mutational Analysis; Female; Genetic Testing; Humans; Male; Multiple System Atrophy; Reverse Transcriptase Polymerase Chain Reaction

To evaluate variations in amyloid beta (Abeta) peptide pattern in cerebrospinal fluid (CSF) in neurodegenerative disorders. A recently established quantitative urea-based Abeta-sodium-dodecylsulfate-polyacrylamide-gel-electrophoresis with western immunoblot (Abeta-SDS-PAGE/immunoblot) revealed a highly conserved Abeta peptide (Abeta1-37, 1-38, 1-39, 1-40, 1-42) pattern in CSF. We asked whether the variation might be useful to further elucidate the overlap between or distinctions among neurodegenerative diseases in Abeta-processing. We used the Abeta-SDS-PAGE/immunoblot to investigate CSF for disease-specific Abeta peptide patterns. CSF samples from 96 patients with mainly clinically diagnosed Alzheimer's disease (n = 15), progressive supranuclear palsy (n = 20), corticobasal degeneration (n = 12), Parkinson's disease (n = 11), multiple systems atrophy (n = 18), and dementia with Lewy-bodies (n = 20) were analysed as well a comparison group (n = 19). The Abeta peptide patterns varied between tauopathies and synucleinopathies and between all diseases and the comparison group, possibly due to the influence of tau and alpha-synuclein on Abeta-processing.

Topics: Aged; Aged, 80 and over; alpha-Synuclein; Alzheimer Disease; Amyloid beta-Peptides; Female; Humans; Male; Middle Aged; Multiple System Atrophy; Protein Processing, Post-Translational; tau Proteins; Tauopathies

Multiple system atrophy (MSA) has been considered a sporadic disease, without patterns of inheritance.. To describe the clinical features of 4 multiplex families with MSA, including clinical genetic aspects.. Clinical and genetic study.. Four departments of neurology in Japan. Patients Eight patients in 4 families with parkinsonism, cerebellar ataxia, and autonomic failure with age at onset ranging from 58 to 72 years. Two siblings in each family were affected with these conditions.. Clinical evaluation was performed according to criteria by Gilman et al. Trinucleotide repeat expansion in the responsible genes for the spinocerebellar ataxia (SCA) series and for dentatorubral-pallidoluysian atrophy (DRPLA) was evaluated by polymerase chain reaction. Direct sequence analysis of coding regions in the alpha-synuclein gene was performed.. Consanguineous marriage was observed in 1 of 4 families. Among 8 patients, 1 had definite MSA, 5 had probable MSA, and 2 had possible MSA. The most frequent phenotype was MSA with predominant parkinsonism, observed in 5 patients. Six patients showed pontine atrophy with cross sign or slitlike signal change at the posterolateral putaminal margin or both on brain magnetic resonance imaging. Possibilities of hereditary ataxias, including SCA1 (ataxin 1, ATXN1), SCA2 (ATXN2), Machado-Joseph disease/SCA3 (ATXN1), SCA6 (ATXN1), SCA7 (ATXN7), SCA12 (protein phosphatase 2, regulatory subunit B, beta isoform; PP2R2B), SCA17 (TATA box binding protein, TBP) and DRPLA (atrophin 1; ATN1), were excluded, and no mutations in the alpha-synuclein gene were found.. Findings in these multiplex families suggest the presence of familial MSA with autosomal recessive inheritance and a genetic predisposition to MSA. Molecular genetic approaches focusing on familial MSA are expected to provide clues to the pathogenesis of MSA.

Topics: Aged; alpha-Synuclein; Brain; Consanguinity; Family Health; Female; Genetic Predisposition to Disease; Humans; Japan; Magnetic Resonance Imaging; Male; Middle Aged; Multiple System Atrophy; Pedigree; Sequence Analysis, DNA; Trinucleotide Repeat Expansion

Levodopa is generally regarded the first choice therapy for parkinsonism associated with multiple system atrophy (MSA-P). However, MSA-P patients often show a poor or unsustained levodopa response which inflicts high dose therapy. This is generally attributed to progressive striatal degeneration with loss of dopamine receptors. Experimental evidence suggests that dopaminergic stimulation may accelerate the striatal disease process in MSA, possibly by pro-oxidative mechanisms. Intact nigrostriatal dopamine release augments striatal lesion size in the unilateral nigral and striatal double lesion rat model of MSA-P. Further, neuronal vulnerability to exogenous oxidative stress is increased in a transgenic MSA mouse model with oligodendroglial alpha-synuclein inclusions. The aim of the present study was to analyze whether high dose levodopa delivery in the transgenic MSA model is associated with neurotoxicity exacerbated by the presence of oligodendroglial alpha-synuclein inclusion pathology. Control and transgenic MSA mice underwent pulsatile treatment with either vehicle, low or high dose levodopa for a period of 1 month. Behavioral and neuropathological indices failed to show evidence for neurotoxic effects of high-dose levodopa in this alpha-synuclein transgenic MSA model. These findings support the idea that high dose levodopa therapy in MSA is not detrimental to the underlying neuropathological process.

Topics: alpha-Synuclein; Analysis of Variance; Animal Diseases; Animals; Antiparkinson Agents; Corpus Striatum; Dose-Response Relationship, Drug; Levodopa; Mice; Mice, Inbred C57BL; Mice, Transgenic; Motor Activity; Multiple System Atrophy; Nerve Tissue Proteins

Depression is a feature of both Lewy body disorders and multiple system atrophy (MSA). Since serotonergic neurons of the rostral raphe have been implicated in depression, we sought to determine whether there is a differential involvement of these neurons in cases with clinically diagnosed dementia with Lewy bodies (DLB) or MSA. We studied the brainstem obtained at autopsy from fourteen patients with diagnosis of DLB and pathological limbic or neocortical stage Lewy body disease, 13 patients with clinical and neuropathological diagnosis of MSA, and 12 controls with no history of neurologic disease. The clinical features of these patients were analyzed retrospectively by reviewing their medical records. Serial sections were immunostained for tryptophan hydroxylase (TrOH) and alpha-synuclein and cell counts were performed in the dorsal raphe (DR), median raphe (MR) and medullary raphe nuclei. There was loss of serotonergic cells in both the DR and MR in DLB compared to control cases: For the DR, the number of cells/section were 53 +/- 6 in DLB versus 159 +/- 13 (P < 0.001) respectively, and for the MR 70 +/- 11 in DLB versus 173 +/- 23 (P < 0.001) respectively. In contrast, these cells were relatively preserved in MSA. The caudal raphe groups were affected both in MSA and in DLB. There is a differential involvement of raphe neurons in DLB and MSA. Although loss of rostral raphe neurons may contribute to depression in DLB, this appears to be less likely in MSA. Factors other than the neurochemical phenotype determine neuronal vulnerability in MSA.

Topics: Aged; Aged, 80 and over; alpha-Synuclein; Cell Count; Depression; Female; Humans; Immunohistochemistry; Inclusion Bodies; Lewy Body Disease; Male; Middle Aged; Multiple System Atrophy; Raphe Nuclei; Tryptophan Hydroxylase

p25alpha is an oligodendroglial protein that can induce aggregation of alpha-synuclein and accumulates in oligodendroglial cell bodies containing fibrillized alpha-synuclein in the neurodegenerative disease multiple system atrophy (MSA). We demonstrate biochemically that p25alpha is a constituent of myelin and a high-affinity ligand for myelin basic protein (MBP), and in situ immunohistochemistry revealed that MBP and p25alpha colocalize in myelin in normal human brains. Analysis of MSA cases reveals dramatic changes in p25alpha and MBP throughout the course of the disease. In situ immunohistochemistry revealed a cellular redistribution of p25alpha immunoreactivity from the myelin to the oligodendroglial cell soma, with no overall change in p25alpha protein concentration using immunoblotting. Concomitantly, an approximately 80% reduction in the concentration of full-length MBP protein was revealed by immunoblotting along with the presence of immunoreactivity for MBP degradation products in oligodendroglia. The oligodendroglial cell bodies in MSA displayed an enlargement along with the relocalization of p25alpha, and this was enhanced after the deposition of alpha-synuclein in the glial cytoplasmic inclusions. Overall, the data indicate that changes in the cellular interactions between MBP and p25alpha occur early in MSA and contribute to abnormalities in myelin and subsequent alpha-synuclein aggregation and the ensuing neuronal degeneration that characterizes this disease.

Topics: alpha-Synuclein; Animals; Axons; Cattle; Cytoplasm; Humans; Inclusion Bodies; Multiple System Atrophy; Myelin Basic Protein; Myelin Sheath; Nerve Tissue Proteins; Oligodendroglia; Swine

The role of microglial activation in multiple system atrophy (MSA) was investigated in a transgenic mouse model featuring oligodendroglial alpha-synuclein inclusions and loss of midbrain dopaminergic neurons by means of histopathology and morphometric analysis. Our findings demonstrate early progressive microglial activation in substantia nigra pars compacta (SNc) associated with increased expression of iNOS and correlating with dopaminergic neuronal loss. Suppression of microglial activation by early long-term minocycline treatment protected dopaminergic SNc neurons. The results suggest that oligodendroglial overexpression of alpha-synuclein may induce neuroinflammation related to nitrosive stress which is likely to contribute to neurodegeneration in MSA. Further, we detected increased toll-like receptor 4 immunoreactivity in both transgenic mice and MSA brains indicating a possible signaling pathway in MSA which needs to be further studied as a candidate target for neuroprotective interventions.

Topics: Aged; alpha-Synuclein; Animals; Corpus Striatum; Disease Progression; Dopamine; Female; Humans; Male; Mice; Mice, Inbred C57BL; Mice, Transgenic; Microglia; Middle Aged; Minocycline; Multiple System Atrophy; Nerve Degeneration; Neuroprotective Agents; Nitric Oxide Synthase Type II; Oligodendroglia; Toll-Like Receptor 4

Impaired transduction of transforming growth factor-beta signaling has recently been implicated in Alzheimer disease. Transforming growth factor-beta signals are transduced by Smads, which are phosphorylated and translocated to the nucleus, where they initiate gene transcription. In Alzheimer disease, neurofibrillary tangles sequester phosphorylated Smad 2/3 (pSmad2/3) and reduce its nuclear translocation. We have now investigated the relationship between pSmad2/3 and phospho-tau in 3 other tauopathies, Pick disease, progressive supranuclear palsy, and corticobasal degeneration, and in 2 alpha-synucleinopathies, dementia with Lewy bodies and multiple system atrophy. In Pick disease, progressive supranuclear palsy, and corticobasal degeneration, pSmad2/3 was demonstrated in neuronal and glial nuclei but also colocalized with cytoplasmic tau inclusions. No pSmad2/3 was detected in glial cytoplasmic inclusions in multiple system atrophy or in Lewy bodies in dementia with Lewy bodies. Our data indicate that phospho-tau but not alpha-synuclein cytoplasmic inclusions bind pSmad2/3. The preservation of neuronal nuclear pSmad2/3 in Pick disease, progressive supranuclear palsy, and corticobasal degeneration suggests that cytoplasmic sequestration of pSmad2/3 is likely to have less impact on transforming growth factor-beta signal transduction in these diseases than in Alzheimer disease.

Topics: Aged; Aged, 80 and over; alpha-Synuclein; Blotting, Western; Brain; Female; Fluorescent Antibody Technique; Humans; Immunohistochemistry; Inclusion Bodies; Lewy Body Disease; Male; Multiple System Atrophy; Neurodegenerative Diseases; Phosphorylation; Pick Disease of the Brain; Protein Transport; Smad Proteins; Supranuclear Palsy, Progressive; tau Proteins

Topics: alpha-Synuclein; Brain; Humans; Inclusion Bodies; Multiple System Atrophy; Nerve Tissue Proteins; Neurons

alpha-Synuclein, a synaptic protein of unknown function, is a major component of Lewy bodies and may play a role in the pathophysiological process of Parkinson's disease (PD). In this study, we measured the plasma alpha-synuclein levels in 105 patients with PD, 38 patients with multiple system atrophy (MSA), and 51 age-matched controls. The alpha-synuclein level was significantly elevated in patients with PD (79.9 +/- 4.0 pg/ml, p < 0.001) and in those with MSA (78.1 +/- 3.5 pg/ml, p = 0.019) compared with the level in controls (76.1 +/- 3.9 pg/ml). The alpha-synuclein level was higher in patients with PD than in those with MSA (79.9 +/- 4.0 vs 78.1 +/- 3.5, p = 0.016). Our study demonstrated that the alpha-synuclein level in plasma is elevated in patients with PD and MSA.

Topics: Adult; alpha-Synuclein; Enzyme-Linked Immunosorbent Assay; Female; Humans; Male; Middle Aged; Multiple System Atrophy; Parkinson Disease

The formation of alpha-synuclein aggregates may be a critical event in the pathogenesis of multiple system atrophy (MSA). However, the role of this gene in the aetiology of MSA is unknown and untested.. The linkage disequilibrium (LD) structure of the alpha-synuclein gene was established and LD patterns were used to identify a set of tagging single nucleotide polymorphisms (SNPs) that represent 95% of the haplotype diversity across the entire gene. The effect of polymorphisms on the pathological expression of MSA in pathologically confirmed cases was also evaluated.. In 253 Gilman probable or definite MSA patients, 457 possible, probable, and definite MSA cases and 1472 controls, a frequency difference for the individual tagging SNPs or tag-defined haplotypes was not detected. No effect was observed of polymorphisms on the pathological expression of MSA in pathologically confirmed cases.

Topics: alpha-Synuclein; Gene Expression; Genotype; Haplotypes; Humans; Linkage Disequilibrium; Multiple System Atrophy; Polymorphism, Single Nucleotide; Sequence Tagged Sites

Topics: alpha-Synuclein; Biomarkers; Humans; Lewy Body Disease; Multiple System Atrophy; REM Sleep Behavior Disorder

Efficacy of high frequency subthalamic nucleus (STN) stimulation has been demonstrated in idiopathic Parkinson's disease (IPD). However, since it may be difficult to differentiate IPD from multiple system atrophy with parkinsonian presentation (MSA-P), a few cases of MSA-P has been treated by deep brain stimulation (DBS) and showed no sustained improvement of clinical signs. We report a patient with a clinical misdiagnosed MSA-P, later confirmed by neuropathological study, who was improved by DBS for one year.. A 63-year-old parkinsonian patient had been treated by levodopa for 6 years with a persistent good response. Over one year he progressively developed disabling fluctuations with severe axial syndrome and vegetative non motor symptoms in off periods. After checking usual contraindications, he was included in surgical procedure protocol (bilateral STN stimulation). During the first year after surgery, the clinical status improved with disappearance of non motor fluctuations, a 45 percent decrease of the OFF UPDRS III score, and a 39 percent reduction of the treatment. However after one year, axial symptoms reappeared with recurrent falls, as well as increasing dysarthry and swallowing difficulties which were only slightly improved by levodopa. He developed severe urinary disorders increased by a prostatic adenoma which led to surgical treatment. During the post operative period, 2 years after DBS, he died suddenly from an unexplained cause. A cerebral autopsy was performed and showed a good position of the two electrodes in the STN. Microscopic studies revealed severe neuronal depletion in the substantia nigra but no Lewy bodies. Immunohistochemical methods demonstrated numerous argyrophilic glial cytoplasmic inclusions positive for alpha-synuclein and ubiquitin in the STN, putamen, globus pallidus, pontine nuclei and cerebellar white matter, significant of MSA.. This case shows that DBS can improve parkinsonian signs in MSA-P with persistent dopa sensitivity. However, probably because of striatal degeneration progression, this improvement is time limited and STN DBS cannot be recommended in MSA.

Topics: Adenoma; alpha-Synuclein; Antiparkinson Agents; Biomarkers; Brain; Brain Chemistry; Combined Modality Therapy; Deep Brain Stimulation; Diagnostic Errors; Disease Progression; Fatal Outcome; Humans; Levodopa; Magnetic Resonance Imaging; Male; Middle Aged; Multiple System Atrophy; Parkinson Disease; Prostatectomy; Prostatic Neoplasms; Substantia Nigra; Subthalamic Nucleus; Ubiquitin

Topics: alpha-Synuclein; Brain; Humans; Immunohistochemistry; Inclusion Bodies; Lewy Bodies; Multiple System Atrophy; Nerve Tissue Proteins; Neuroglia; Neurons; Parkinson Disease

To study the topographic distribution of the pathology in multiple system atrophy (MSA). Pattern analysis was carried out using alpha-synuclein immunohistochemistry in 10 MSA cases. The glial cytoplasmic inclusions (GCI) were distributed randomly or in large clusters. The neuronal inclusions (NI) and abnormal neurons were distributed in regular clusters. Clusters of the NI and abnormal neurons were spatially correlated whereas the GCI were not spatially correlated with either the NI or the abnormal neurons. The data suggest that the GCI represent the primary change in MSA and the neuronal pathology develops secondary to the glial pathology.

Topics: Aged; alpha-Synuclein; Brain; Female; Frontal Lobe; Humans; Inclusion Bodies; Male; Middle Aged; Multiple System Atrophy; Neurons; Putamen

Topics: alpha-Synuclein; Brain Diseases; Calcinosis; Cerebellum; Humans; Magnetic Resonance Imaging; Male; Middle Aged; Multiple System Atrophy; Pons

Parkinson's disease (PD) and multiple system atrophy (MSA) are characterized pathologically by inclusions in the brain containing alpha-synuclein, which is phosphorylated at serine 129. alpha-Synuclein is present not only in the brain but also in platelets; platelets have previously been used to study mitochondrial function in PD. We undertook to determine whether alpha-synuclein extracted from platelets of patients with PD and MSA is phosphorylated at serine 129 and could be used as a peripheral marker of these disorders. Immunoblots indicated that platelet alpha-synuclein is not phosphorylated at serine 129 in PD and MSA.

Topics: Adult; Aged; alpha-Synuclein; Animals; Arabidopsis Proteins; Blood Platelets; Blotting, Western; Carrier Proteins; Female; Humans; Male; Mice; Mice, Transgenic; Middle Aged; Multiple System Atrophy; Parkinson Disease; Serine

Adult polyglucosan body disease (APGBD) is a rare disorder affecting the central and peripheral nervous systems and in which parkinsonism is unusual. A 71-year-old man presented levodopa-unresponsive parkinsonism with urinary incontinence and recurrent syncopes of 6 years standing masquerading as atypical parkinsonism of the multiple system atrophy (MSA-P) type. Brain histopathology demonstrated massive accumulation of polyglucosan bodies particularly in the putamen. In addition, there were dense alpha-synuclein-positive cytoplasmic oligodendroglial inclusions in the pons and in the middle cerebellar peduncle. These inclusions may be either due to the chance association of MSA-P with APGBD, or pathologically related to APGBD.

Topics: Aged; alpha-Synuclein; Glial Fibrillary Acidic Protein; Glucans; Humans; Immunohistochemistry; Inclusion Bodies; Lewy Bodies; Male; Multiple System Atrophy; Nerve Tissue Proteins; Parkinsonian Disorders; Review Literature as Topic; Staining and Labeling; Synucleins

Multiple system atrophy (MSA) is a progressive neurodegenerative disorder characterized by parkinsonism unresponsive to dopaminergic therapy, cerebellar ataxia, and dysautonomia. Neuropathology shows a characteristic neuronal multisystem degeneration that is associated with widespread oligodendroglial alpha-synuclein (alpha-SYN) inclusions. Presently no animal model completely replicates the specific neuropathology of MSA. Here we investigated the behavioral and pathological features resulting from oligodendroglial alpha-SYN overexpression in transgenic mice exposed to mitochondrial inhibition by 3-nitropropionic acid. In transgenic mice 3-nitropropionic acid induced or augmented motor deficits that were associated with MSA-like pathology including striatonigral degeneration and olivopontocerebellar atrophy. Widespread astrogliosis and microglial activation were also observed in the presence of alpha-SYN in oligodendrocytes. Our results indicate that combined mitochondrial inhibition and overexpression of oligodendroglial alpha-SYN generates a novel model of MSA that may be useful for evaluating both pathogenesis and treatment strategies.

Topics: alpha-Synuclein; Animals; Antigens, CD; Antigens, Differentiation, Myelomonocytic; Astrocytes; Disease Models, Animal; Image Processing, Computer-Assisted; Immunohistochemistry; Mice; Mice, Transgenic; Microglia; Movement; Movement Disorders; Multiple System Atrophy; Nerve Tissue Proteins; Neurons; Nitro Compounds; Oligodendroglia; Oxidative Stress; Propionates; Synucleins; Time Factors

Transgenic (Tg) mice overexpressing human wild-type alpha-synuclein in oligodendrocytes under the control of the 2,' 3'-cyclic nucleotide 3'-phosphodiesterase (CNP) promoter are shown here to recapitulate features of multiple system atrophy (MSA), including the accumulation of filamentous human alpha-synuclein aggregates in oligodendrocytes linked to their degeneration and autophagocytosis of myelin. Significantly, endogenous mouse alpha-synuclein also accumulated in normal and degenerating axons and axon terminals in association with oligodendroglia and neuron loss and slowly progressive motor impairments. Our studies demonstrate that overexpression of alpha-synuclein in oligodendrocytes of mice results in MSA-like degeneration in the CNS and that alpha-synuclein inclusions in oligodendrocytes participate in the degeneration of neurons in MSA.

Topics: 2',3'-Cyclic Nucleotide 3'-Phosphodiesterase; alpha-Synuclein; Animals; Axons; Central Nervous System; Disease Models, Animal; Humans; Inclusion Bodies; Mice; Mice, Transgenic; Microscopy, Electron, Transmission; Multiple System Atrophy; Myelin Sheath; Nerve Tissue Proteins; Neuroglia; Neurons; Oligodendroglia; Phagocytosis; Phosphoric Diester Hydrolases; Presynaptic Terminals; Promoter Regions, Genetic; Synucleins; Wallerian Degeneration

Topics: Adult; alpha-Synuclein; Ataxins; Cerebellar Diseases; Fluorescent Antibody Technique; Humans; Inclusion Bodies; Male; Microscopy, Confocal; Multiple System Atrophy; Nerve Tissue Proteins; Neuroglia; Synucleins

We immunohistochemically examined the sympathetic ganglia (SG) and brains of 26 patients with multiple system atrophy (MSA), 19 age-matched controls, and 25 patients with amyotrophic lateral sclerosis (ALS). alpha-Synuclein-immunoreactive structures were found in the neuronal cytoplasm and processes of the SG in 11 of the 26 MSA cases (42.3%) and 1 of the 25 ALS cases (4%), but not in the 19 controls. No alpha-synuclein-immunoreactive structures were found in Schwann cells or the neuronal nucleus. Mean disease duration of MSA cases with alpha-synuclein-immunoreactive structures was significantly longer than that of MSA cases without alpha-synuclein-immunoreactive structures. alpha-Synuclein-immunoreactive structures in 4 cases proved to be Lewy bodies (LB) based on hematoxylin-eosin staining. A few LB were also found in the brains of 3 of these 4 cases. In the other 7 MSA cases, diffuse or focal neuronal cytoplasmic aggregates and swollen neurites were detected with alpha-synuclein immunostaining, but not with hematoxylin-eosin staining. However, a few LB-like structures with ring-like staining were observed in those aggregates, which suggested those aggregates had progressed to form LB. Immunoelectron microscopically, those aggregates were composed of filaments and granular materials which closely resembled the ultrastructural features of LB. We inferred that alpha-synuclein aggregates found in the SG in our study evidenced LB-related pathologies. MSA, a type of synucleinopathy, is characterized by glial cytoplasmic inclusions in oligodendrocytes, but also frequently develops LB pathology in the late stage, especially in the SG.

Topics: Aged; Aged, 80 and over; alpha-Synuclein; Amyotrophic Lateral Sclerosis; Female; Ganglia, Sympathetic; Humans; Immunohistochemistry; Inclusion Bodies; Lewy Bodies; Male; Microscopy, Immunoelectron; Middle Aged; Multiple System Atrophy; Nerve Tissue Proteins; Neurons; Synucleins; Time Factors

The cardinal pathological features of multiple system atrophy (MSA) are the presence of glial cytoplasmic inclusions (GCIs) in oligodendrocytes and loss of oligodendrocytes. To understand the mechanisms underlying MSA, we examined the effects of overexpression of human alpha-synuclein (halpha-syn) in CG-4 oligodendrocytic progenitor cells. CG-4 cells overexpressing halpha-syn (halpha-syn CG-4) demonstrated severely impaired adhesion and increased cell death when plated on fibronectin compared to laminin. The expression of the alphav integrin subunit in whole cell lysates was also significantly downregulated in halpha-syn CG-4. These results demonstrate a cytotoxic consequence of halpha-syn overexpression in CG-4. This cytotoxicity appears to be the result of alterations in cell-extracellular matrix interactions, where impaired adhesion to fibronectin is associated with downregulation of the alphav integrin subunit and increased cell death. It may, therefore, be one of the mechanisms underlying the loss of oligodendrocytes in MSA.

Topics: alpha-Synuclein; Animals; Animals, Newborn; Cell Adhesion; Cell Death; Cell Line; Cells, Cultured; Down-Regulation; Extracellular Matrix; Fibronectins; Genetic Vectors; Humans; Inclusion Bodies; Integrin alphaV; Multiple System Atrophy; Myelin Sheath; Nerve Tissue Proteins; Oligodendroglia; Rats; Synucleins; Transfection

Lewy bodies (LBs) of idiopathic Parkinson's disease and glial cytoplasmic inclusions (GCIs) of multiple system atrophy are pathological deposits both composed of phosphorylated alpha-synuclein woven into different filaments. Although both LBs and GCIs are considered to be hallmarks for each independent synucleinopathy, until now they could not be clearly distinguished on the basis of their biochemical or immunohistochemical features. We have examined possible differences in their argyrophilic features and their relation to synuclein-like or ubiquitin-like immunoreactivity (IR). Pairs of mirror sections from different brain areas were triple-fluorolabeled with an anti-alpha-synuclein antibody, an anti-ubiquitin antibody and thiazin red (TR), a fluorochrome that labels fibrillary structures such as Lewy bodies or neurofibrillary tangles. One of the paired sections was subsequently stained using the Campbell-Switzer method (CS), and the other by the Gallyas-Braak method (GB). By comparing of the same microscopic field on the paired fluorolabeled sections, subsequently silver-stained with either CS or GB, five different profiles of each structure could be determined: alpha-synuclein-like IR, ubiquitin-like IR, affinity to TR, argyrophilia with CS or GB. GCIs exhibited argyrophilia with both CS and GB but lacked affinity to TR. In contrast, LBs exhibited argyrophilia with CS but not with GB and some affinity to TR. These disease-specific profiles of argyrophilia were consistent, and were not influenced by areas or cases examined. Although immunohistochemical features of LBs and GCIs were similar in exhibiting IR for alpha-synuclein and ubiquitin, the contrast in their argyrophilic profiles may indicate possible differences in the molecular composition or conformation of alpha-synuclein. Even though these empirical differences still remain to be explained, awareness of this clear distinction is potentially of diagnostic and pathological relevance.

Topics: Aged; alpha-Synuclein; Brain; Diagnosis, Differential; Female; Humans; Immunohistochemistry; Inclusion Bodies; Lewy Bodies; Male; Middle Aged; Multiple System Atrophy; Neuroglia; Neurons; Organic Chemicals; Parkinson Disease; Predictive Value of Tests; Silver Staining; Ubiquitin

Multiple system atrophy (MSA), a sporadic progressive synucleinopathy of advanced age, is separated into two clinic opathological subtypes: MSA-P (striatonigral degeneration [SND]) with predominant parkinsonian features and MSA-C (olivopontocerebellar atrophy [OPCA]) with predominant cerebellar ataxia. We propose a novel morphological grading system for both subtypes to compare lesion intensities and their possible clinical validity. Forty-two autopsy cases of MSA were separated into four grades (SND 0-III and OPCA 0-III) based on semiquantitative assessment of neuronal loss, astrogliosis, and presence of alpha-synuclein-positive glial cytoplasmic inclusions (GCI) in striatum, globus pallidus, substantia nigra, pontine basis, cerebellum, and inferior olives. Whereas a recent grading system restricted to SND reflected disease progression and dopa-responsiveness, there was considerable variation in the morphological combination between SND and OPCA, with only around half the cases with OPCA II (moderate) and III (severe) showing comparable grades of both types, whereas OPCA 0 and I (no or little degeneration) was combined with all grades of SND. Twenty-two cases showing OPCA 0 + SND II (n = 3), OPCA I + SND I-II (n = 11), and OPCA I + SND III (n = 8) were classified as pure or predominant SND, consistent with MSA-P. Twenty cases showing OPCA II + SND II/III (n = 7) and OPCA III + SND III (n = 13) were classified as predominant OPCA, consistent with MSA-C. In MSA-P, the mean age of onset was higher than it was in MSA-C (55.1 vs. 50.5 years), but the mean duration of illness was shorter in MSA-P (5.3 vs. 6.7 years). Presenting symptoms in MSA-P were mainly parkinsonism, whereas in MSA-C they were mainly gait disorders (14 vs. 1; P < 0.001). Among clinical key symptoms, parkinsonism was more frequent than were cerebellar signs in MSA-P; in MSA-C it was the reverse (P < 0.01), whereas other symptoms (autonomic/urinary failure) showed no differences. Parkinsonism was infrequent in MSA-C even when OPCA was associated with SND, suggesting a masking effect by cerebellar system involvement. High terminal Hoehn and Yahr stages were more frequent in MSA-P (P < 0.01), some with good-to-moderate initial levodopa (L-dopa) response. Although the proposed morphological grading of both MSA-P and -C correlates well with initial symptoms and clinical key features of both types, further prospective studies are required to validate the clinical utility of the proposed MSA gradi

Topics: alpha-Synuclein; Cerebellar Ataxia; Corpus Striatum; Diagnosis, Differential; Disease Progression; Humans; Middle Aged; Multiple System Atrophy; Nerve Degeneration; Olivopontocerebellar Atrophies; Severity of Illness Index

alpha-Synuclein represents the major constituent of oligodendroglial cytoplasmic inclusions, the hallmark lesion of multiple system atrophy (MSA), a progressive disorder that is associated with selective degenerative cell loss in basal ganglia, cerebellum, brainstem, and spinal cord. The role of abnormal alpha-synuclein aggregation in oligodendroglial cells is still obscure, in particular, whether alpha-synuclein might impair oligodendroglial and, secondarily, neuronal integrity of those cells in the diseased brain. In an attempt to answer some of these questions, we have developed an "in vitro model of MSA" by expressing the wild-type or C-terminally truncated form of alpha-synuclein in glial cell cultures. With this simplified system, we have demonstrated that alpha-synuclein significantly affects the survival of glia and its vulnerability to environmental stress, which might represent a major step in the pathogenesis of MSA.

Topics: alpha-Synuclein; Basal Ganglia; Brain Stem; Cerebellum; Disease Progression; Environment; Humans; In Vitro Techniques; Microglia; Multiple System Atrophy; Nerve Degeneration; Oxidative Stress; Spinal Cord; Tumor Necrosis Factor-alpha

Multiple system atrophy (MSA) is a sporadic adult-onset neurodegenerative disorder of unknown etiology clinically characterized by a combination of parkinsonian, pyramidal, and cerebellar signs. Levodopa-unresponsive parkinsonism is present in 80% of MSA cases, and this dominant clinical presentation (MSA-P) is associated with a combined degeneration of the substantia nigra pars compacta and the striatum in anatomically related areas. The limited knowledge of the pathophysiology of MSA and the lack of therapeutic strategies prompted the development of lesion models reproducing striatonigral degeneration, the substrate of levodopa-unresponsive parkinsonism in MSA-P. This method was carried out first in rats with two different stereotaxic strategies using either two neurotoxins ("double toxin-double lesion") or a single neurotoxin ("single toxin-double lesion"). Double-lesioned rat models showed severe motor impairment compared to those with a single nigral or striatal lesion and helped to mimic different stages of the disease. Systemic models were also developed in mice and primates using the nigral toxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) and the striatal toxin 3-nitropropionic (3-NP). In mice, although MPTP reduced the subsequent sensitivity to 3-NP in a sequential lesion, simultaneous nigral and striatal insults were shown to exacerbate striatal damage. MPTP-treated monkeys displayed a significant worsening of parkinsonism and a loss of levodopa-responsiveness after the appearance of hindlimb dystonia and striatal lesion formation induced by subsequent 3-NP intoxication. The different species and intoxication paradigms used will be useful to investigate functional changes in substantia nigra and striatum and to define neuroprotective, neurorestorative, or symptomatic therapeutic strategies.

Topics: alpha-Synuclein; Animals; Antiparkinson Agents; Corpus Striatum; Levodopa; Macaca fascicularis; Mice; MPTP Poisoning; Multiple System Atrophy; Oxidopamine; Parkinsonian Disorders; Point Mutation; Rats; Substantia Nigra

(Oligodendro)glial cytoplasmic inclusions composed of the protein alpha-synuclein (alphaSYN) are the neuropathological hallmark lesions of multiple system atrophy (MSA). The recent generation of transgenic mouse models of oligodendroglial alpha-synucleinopathy has enabled studies to investigate how alphaSYN causally contributes to MSA neuropathology. Moreover, human disease-specific pathological modifications of alphaSYN were recapitulated in transgenic mice, including insolubility, phosphorylation at serine-129, and ubiquitination. Thus, the transgenic mice will be useful tools to assess cellular risk factors, such as protein folding stress, protein kinase hyperactivity, and failure of the ubiquitin-proteasome system. Moreover, transgenic mice expressing a hyperactive alpha(1B)-adrenergic receptor mutant showed evidence of alphaSYN pathology in oligodendrocytes, adding dysregulated adrenergic neurotransmission to the list of potential risk factors of MSA. Finally, a double-transgenic mouse model expressing both alphaSYN and tau revealed synergistic fibrillization of these two proteins, providing an animal model for the not uncommon neuropathological finding of concomitant alpha-synucleinopathy and tauopathy within oligodendrocytes. Despite the progress made modeling MSA neuropathology in the transgenic mouse models, the molecular mechanism of how alphaSYN aggregation in oligodendrocytes causes neurodegeneration remains to be established. Moreover, it will be important to understand what defines the predilection sites most severely affected by striatonigral degeneration (MSA-P) and olivopontocerebellar atrophy (MSA-C), respectively.

Topics: alpha-Synuclein; Animals; Disease Models, Animal; In Situ Hybridization; Mice; Mice, Transgenic; Multiple System Atrophy; Oligodendroglia; Phosphorylation; Point Mutation; tau Proteins

Alpha-synuclein (alphaS) and ubiquitin (Ub) are shared constituents of glial cytoplasmic inclusions (GCIs) and Lewy bodies (LBs), both composed of fibrillary structures. Staining profiles of GCIs were investigated with triple immunofluorescence involving immunostaining for alphaS and Ub, both amplified with catalyzed reporter deposition, and a fluorochrome, thiazin red (TR) that has an affinity to fibrillary structures. After observation for the triple-fluorescent images, the sections were subsequently stained with the Gallyas-Braak method. Sections of putamen, cerebellar white matter and motor cortex from patients suffering from multiple system atrophy (MSA) with varying duration of the disease (4-15 years) were quantified for these staining profiles of Gallyas-positive GCIs. Although most of GCIs were positive for Ub and variably positive for alphaS, they were consistently negative for TR. The result was opposite in LBs in Lewy body disease with variable affinity to TR, suggesting that the construction of GCIs is different from that of LBs. These four staining features (alphaS, Ub, TR and Gallyas) alone failed to exhibit apparent correlation with disease duration, lesion site or severity of degeneration as reported previously. The fraction of alphaS-negative and Ub-positive GCIs, however, linearly increased along the disease progression, while that of alphaS-positive and Ub-negative GCIs decreased in contrast. This reciprocal change suggests that alphaS immunoreactivity in GCIs is being replaced by Ub immunoreactivity during the disease progression, which resulted in the ultimate predominance of alphaS-negative and Ub-positive GCIs in the most advanced case. Interestingly, this predominance of alphaS-negative and Ub-positive GCIs was a feature of motor cortex, where degeneration usually remains mild in spite of robust appearance of Gallyas-positive GCIs. Another fraction, alphaS-positive and Ub-positive GCIs were frequent in cerebellar white matter, suggesting that GCI evolution is heterogeneous and dependent also on area examined. Progressive accumulation of Ub with concomitant disappearance of alphaS epitope and their colocalization, partly shared with LBs, may represent a process of GCI formation, possibly linked to an aspect of degeneration in MSA.

Topics: Aged; alpha-Synuclein; Female; Fluorescent Antibody Technique; Humans; Inclusion Bodies; Male; Middle Aged; Multiple System Atrophy; Neuroglia; Regression Analysis; Severity of Illness Index; Staining and Labeling; Ubiquitin

alpha-Synuclein is a major constituent of glial cytoplasmic inclusions (GCIs), which are pathognomic for multiple system atrophy (MSA). We have previously demonstrated that in normal human brain, alpha-synuclein mRNA has a restricted pattern of neuronal expression and no apparent glial expression. The current study used double-label in situ hybridization to determine if alpha-synuclein mRNA is expressed by oligodendroglia of MSA cases. Analysis of MSA brain tissue revealed depletion of regional signal for this transcript in many brain areas due to extensive neurodegeneration. Cellular analysis of oligodendroglia in crus cerebri, a GCI-rich region ventral to substantia nigra, revealed an absence of alpha-synuclein mRNA signal in control and MSA cases. However, an abundance of this transcript was detected in melanin-containing neurons of substantia nigra. Therefore, oligodendroglia do not express alpha-synuclein mRNA in control and MSA cases suggesting that involvement of alpha-synuclein in GCI pathology of MSA is due to its ectopic presence in oligodendroglia.

Topics: Aged; Aged, 80 and over; alpha-Synuclein; Brain; Gene Expression Regulation; Humans; Middle Aged; Multiple System Atrophy; Oligodendroglia; RNA, Messenger

Multiple system atrophy (MSA) is a progressive, neurodegenerative disease characterized by parkinsonism, ataxia, autonomic dysfunction, and accumulation of alpha-synuclein (alpha-syn) in oligodendrocytes. To better understand the mechanisms of neurodegeneration and the role of alpha-syn accumulation in oligodendrocytes in the pathogenesis of MSA, we generated transgenic mouse lines expressing human (h) alpha-syn under the control of the murine myelin basic protein promoter. Transgenic mice expressing high levels of halpha-syn displayed severe neurological alterations and died prematurely at 6 months of age. Furthermore, mice developed progressive accumulation of halpha-syn-immunoreactive inclusions in oligodendrocytes along the axonal tracts in the brainstem, basal ganglia, cerebellum, corpus callosum, and neocortex. The inclusions also reacted with antibodies against phospho-serine (129) halpha-syn and ubiquitin, and halpha-syn was found in the detergent-insoluble fraction. In high-expresser lines, the white matter tracts displayed intense astrogliosis, myelin pallor, and decreased neurofilament immunostaining. Accumulation of halpha-syn in oligodendrocytes also leads to prominent neurodegenerative changes in the neocortex with decreased dendritic density and to loss of dopaminergic fibers in the basal ganglia. The oligodendrocytic inclusions were composed of fibrils and accompanied by mitochondrial alterations and disruption of the myelin lamina in the axons. Together, these studies support the contention that accumulation of alpha-syn in oligodendrocytes promotes neurodegeneration and recapitulates several of the key functional and neuropathological features of MSA.

Topics: alpha-Synuclein; Animals; Disease Models, Animal; Humans; Male; Mice; Mice, Inbred C57BL; Mice, Inbred DBA; Mice, Transgenic; Middle Aged; Multiple System Atrophy; Nerve Degeneration; Oligodendroglia; Promoter Regions, Genetic

We examined neuronal and oligodendroglial nuclear inclusions and neurites in the pontine base of multiple system atrophy brains using an antibody to alpha-synuclein. Immunohistochemistry showed alpha-synuclein positive inclusions in the nuclei of some neurons and oligodendroglia. Immunoelectron microscopy showed that the labeled inclusions were composed of bundles of tightly packed straight filaments with a diameter of 10-20 nm. The filaments were similar, if not identical, in morphology and immunoreactivity, to those found in the soma of neurons and oligodendrocytes with glial cytoplasmic inclusions. In addition, similar immuno-positive filaments were found in dendrites or unmyelinated axons, but not in myelinated axons. The functional significance of these inclusions in terms of transcriptional and axonal dysfunction is unknown.

Topics: Actin Cytoskeleton; alpha-Synuclein; Cell Nucleus; Dendrites; Humans; Immunohistochemistry; Intranuclear Inclusion Bodies; Microscopy, Electron; Multiple System Atrophy; Nerve Fibers, Unmyelinated; Nerve Tissue Proteins; Neurites; Neurofilament Proteins; Neurons; Oligodendroglia; Pons; Synucleins

We immunohistochemically examined the brain and peripheral sympathetic ganglia from eight patients with multiple system atrophy (MSA), using an antibody specific for phosphorylated alpha-synuclein (anti-PSer129). Phosphorylated alpha-synuclein was deposited in five cellular locations: oligodendroglial cytoplasm and nucleus, and neuronal cytoplasm, processes and nucleus. Many neuronal cytoplasmic inclusions (NCIs) were found in the pontine and inferior olivary nuclei and, to a lesser extent, in the substantia nigra, locus ceruleus, and neocortical and hippocampal neurons. NCIs were also found in the sympathetic ganglia in two out of the eight cases. Moreover, anti-PSer129 immunohistochemistry revealed extensive neuropil pathology; swollen neurites were abundant in the pontine nucleus, delicate neurites were observed in the deeper layers of the cerebral cortex and thalamus, and neuropil threads and dot-like structures were distributed in the basal ganglia and brainstem. Diffuse neuronal cytoplasmic staining (pre-NCI) was frequently found in the pontine and inferior olivary nuclei. Thus, the widespread accumulation of phosphorylated alpha-synuclein in both glial and neuronal cells is a pathological feature in patients suffering from MSA.

Topics: Aged; Aged, 80 and over; alpha-Synuclein; Brain; Cell Count; Cellular Structures; Ganglia, Sympathetic; Humans; Immunohistochemistry; Inclusion Bodies; Lewy Bodies; Lewy Body Disease; Middle Aged; Multiple System Atrophy; Nerve Tissue Proteins; Neurons; Parkinson Disease; Postmortem Changes; Staining and Labeling; Synucleins

In cases of multiple system atrophy (MSA), glial cytoplasmic inclusions (GCI) were distributed randomly or present in large diffuse clusters (>1,600 microm in diameter) in most areas studied. These spatial patterns contrast with those reported for filamentous neuronal inclusions in the tauopathies and alpha-synucleinopathies.

Topics: Aged; Aged, 80 and over; alpha-Synuclein; Brain; Diagnosis, Differential; Female; Humans; Inclusion Bodies; Male; Middle Aged; Multiple System Atrophy; Nerve Net; Nerve Tissue Proteins; Neurofibrils; Neuroglia; Neurons; Olivopontocerebellar Atrophies; Shy-Drager Syndrome; Striatonigral Degeneration; Synucleins

Multiple system atrophy (MSA) is a neurodegenerative disorder that predominantly affects motor-related neuroanatomic structures. The role of microglia in MSA is unknown. To address this issue, we conducted quantitative image studies on the brains from 13 cases of MSA, comprising 8 cerebellar and 5 parkinsonian variants. Microglial and glial cytoplasmic inclusion (GCI) burdens were determined with image analysis on brain sections immunostained with antibodies to HLA-DR and alpha-synuclein. Many activated microglia, as well as GCIs, were noted in motor-related structures, including the cerebellar input, extrapyramidal motor, and pyramidal motor structures, but not in the cerebellar output structures. This result indicates that microglial activation, as well as the distribution of GCIs, is system-specific in MSA. The correlation analysis between the microglial and GCI burdens yielded variable yet significant correlations in the cerebellar input, extrapyramidal motor, and pyramidal motor systems, but not in the cerebellar output system. This result suggests that microglial activation is at least partly determined by GCIs or oligodendroglial alpha-synuclein in specific neuroanatomic systems affected in MSA. Taken together, considering the known toxic effects of microglia in neurodegenerative diseases, microglia may play a part in the development of system-specific tissue injuries, contributing to the system-bound clinical and pathological phenotypes.

Topics: Aged; alpha-Synuclein; Brain; Female; HLA-DR Antigens; Humans; Image Processing, Computer-Assisted; Immunohistochemistry; Inclusion Bodies; Male; Microglia; Middle Aged; Multiple System Atrophy; Nerve Tissue Proteins; Synucleins

Mutations in the PARK7 gene DJ-1 are associated with recessive hereditary Parkinson's disease (PD). Fibrillar inclusions of alpha-synuclein comprise the neuropathological hallmarks of PD and related Lewy body diseases as well as multiple system atrophy (MSA). Moreover, neuronal and glial inclusions containing tau have been observed in alpha-synucleinopathy patients. Using a collection of antibodies against DJ-1, we have performed a comprehensive investigation of DJ-1 in alpha-synucleinopathies and tauopathies. DJ-1 was abundantly expressed in reactive astrocytes of patients with neurodegenerative diseases. Likewise, DJ-1 antiserum immunostained reactive astrocytes that became abundant with disease progression in the brain stem of transgenic mice expressing mutant [A30P]alpha-synuclein. Human Lewy bodies as well as Lewy body-like inclusions in the alpha-synuclein transgenic mice were DJ-1 negative. Neuronal tau inclusions were DJ-1 immunopositive in Pick's disease (PiD), corticobasal degeneration (CBD), progressive supranuclear palsy (PSP), and Alzheimer's disease. In addition, we found DJ-1-immunopositive glial inclusions in CBD, PSP and MSA. Biochemical extraction experiments revealed the specific presence of insoluble, modified DJ-1 in PiD and MSA. Our results suggest that DJ-1 is up-regulated in reactive astrocytes as well as in neuronal and glial cells with specific alpha-synucleinopathy and tauopathy.

Topics: Adult; Aged; Aged, 80 and over; alpha-Synuclein; Animals; Blotting, Western; Epitope Mapping; Female; Humans; Immunohistochemistry; Intracellular Signaling Peptides and Proteins; Male; Mice; Mice, Transgenic; Middle Aged; Multiple System Atrophy; Nerve Tissue Proteins; Oncogene Proteins; Pick Disease of the Brain; Protein Deglycase DJ-1; Synucleins; tau Proteins; Tauopathies

We examined the distribution of Pael-R, a newly identified substrate for Parkin, in Parkinson's disease (PD) and multiple system atrophy (MSA). Pael-R, Parkin, alpha-synuclein, and ubiquitin accumulated in Lewy bodies (LBs) and neurites. Pael-R was localized in the core of LBs. Parkin and alpha-synuclein accumulated in the halo, neuronal cell bodies, and processes. These findings potentially suggest the involvement of Pael-R in LB formation, and protection role of Parkin in Pael-R-mediated neurotoxicity in PD. The absence of Pael-R and Parkin in glial cytoplasmic inclusions (GCIs) in MSA implies a distinct pathway involved in the formation of LBs and GCIs.

Topics: Aged; Aged, 80 and over; alpha-Synuclein; Brain; Female; Humans; Immunohistochemistry; Lewy Bodies; Male; Middle Aged; Multiple System Atrophy; Nerve Tissue Proteins; Neurites; Neurons; Parkinson Disease; Receptors, G-Protein-Coupled; Synucleins; Ubiquitin; Ubiquitin-Protein Ligases

Oligodendroglial cytoplasmic inclusions composed of alpha-synuclein filamentous aggregates are the pathological hallmark of multiple system atrophy (MSA). We found that cortical tissue from MSA cases contains increased detergent-resistant high-molecular-weight alpha-synuclein species. To analyse these species, we immunopurified alpha-synuclein aggregates from pathological samples and examined their ultrastructures using scanning electron and atomic force microscopies. Purified aggregates consisted of bundles of filaments. After treatment with 1% sarcosine or 2% 3-[(3-cholamidopropyl) dimethyl-ammonio]-1-propanesulfonate (CHAPS) detergents, we observed frequent 30-50 nm annular particles, probably released from pathological aggregates due to the dissociation of filaments by the detergents. Antibody recognition imaging using a specific anti-alpha-synuclein antibody confirmed that the annular structures were positive for alpha-synuclein. In contrast to pathological alpha-synuclein, detergent treatment of recombinant alpha-synuclein yielded only smaller, 10-18 nm spherical particles. Our results demonstrate that detergent treatment of pathological MSA alpha-synuclein aggregates, but not recombinant alpha-synuclein, yields discrete alpha-synuclein-positive species with annular morphologies. The ability of the pathological alpha-synuclein to form annular aggregates may be an important factor contributing to the toxicity of the protein in disease that may have implications in designing therapeutic strategies aimed at detoxifying alpha-synuclein aggregates.

Topics: alpha-Synuclein; Brain Chemistry; Cholic Acids; Detergents; Humans; Inclusion Bodies; Macromolecular Substances; Microscopy, Atomic Force; Microscopy, Electron, Scanning; Molecular Weight; Multiple System Atrophy; Nerve Tissue Proteins; Oligodendroglia; Particle Size; Recombinant Proteins; Sarcosine; Synucleins

Multiple system atrophy (MSA) is a sporadic neurodegenerative disease characterized by the presence of neuronal and oligodendroglial alpha-synuclein aggregates. To investigate the relationship between the occurrence of neuronal cytoplasmic and intranuclear inclusions (NCIs and NNIs, respectively) and the progression of neuronal degeneration, we performed a quantitative analysis of the pontine and inferior olivary nuclei based on 14 cases of MSA. alpha-Synuclein immunohistochemistry revealed that NCIs and NNIs were present in both brain nuclei in all the cases. The average incidence of NCIs in the pontine and inferior olivary nuclei was 9.1% and 25.8%, respectively, and that of NNIs was 9.2% and 9.0%, respectively. The number of NNIs was strongly correlated with that of neurones in the pontine and inferior olivary nuclei. Although the number of NCIs was not correlated with the neuronal population in both nuclei, the NCI count in patients with moderate MSA was higher than in patients with mild MSA. The NNI count was much higher than the NCI count in the pontine nucleus in four patients, and was the same in the olivary nucleus in three of the four patients. Moreover, the neuronal population in the NNI-predominant cases was significantly higher than in the NCI-predominant cases. These findings suggest that NCI formation is accelerated by the progression of the disease process, and that in MSA, NNI formation is an earlier phenomenon than NCI formation.

Topics: Aged; Aged, 80 and over; alpha-Synuclein; Female; Humans; Immunohistochemistry; Inclusion Bodies; Intranuclear Inclusion Bodies; Male; Microscopy, Immunoelectron; Middle Aged; Multiple System Atrophy; Nerve Tissue Proteins; Neurons; Olivary Nucleus; Pons; Synucleins

Neurodegenerative diseases share symptoms suggested to be related to the serotonergic system. To evaluate the involvement of serotonergic raphe nuclei, we compared the percentage of neurons synthesizing serotonin in the nucleus centralis superior (NCS), raphe obscurus and pallidus (NROP) in Alzheimer's disease (AD), progressive supranuclear palsy (PSP), Parkinson's disease (PD), multiple system atrophy (MSA), and control brains. We used immunohistochemistry for tryptophan hydroxylase (TpOH), phosphorylated tau, and alpha-synuclein. We observed a significant decrease in the NCS in the NROP in AD, but a significant increase in PSP and MSA. Cytoskeletal pathology was present in the NCS and NROP to a variable degree. We conclude that there is disease- and nucleus-specific alteration of serotonin synthesis in the raphe.

Topics: Aged; alpha-Synuclein; Alzheimer Disease; Female; Humans; Male; Medulla Oblongata; Middle Aged; Multiple System Atrophy; Nerve Tissue Proteins; Neurodegenerative Diseases; Neurons; Parkinson Disease; Phosphorylation; Pons; Protein Processing, Post-Translational; Raphe Nuclei; Serotonin; Supranuclear Palsy, Progressive; Synucleins; tau Proteins; Tryptophan Hydroxylase

We carried out immunohistochemical examinations of the brains (cerebella) of patients who had suffered from Parkinson's disease (PD), diffuse Lewy body disease (DLBD) or multiple system atrophy (MSA), using antibodies specific for alpha-synuclein. Alpha-synuclein-positive doughnut-shaped structures were found occasionally in the cerebellar molecular layer in some of these patients. Double-labeling immunofluorescence and immunoelectron microscopy studies revealed that these alpha-synuclein-positive doughnut-shaped structures were located in the glial fibrillary acidic protein-positive radial processes of Bergmann glia, corresponding to the outer area of Lewy body-like inclusions, and consisted of granulo-filamentous structures. These findings indicate that, although not frequently, Bergmann glia of the cerebellum are also the targets of alpha-synuclein pathology in alpha-synucleinopathies such as PD, DLBD and MSA.

Topics: Aged; Aged, 80 and over; alpha-Synuclein; Cerebellum; Female; Humans; Immunohistochemistry; Lewy Body Disease; Male; Microglia; Microscopy, Immunoelectron; Middle Aged; Multiple System Atrophy; Nerve Tissue Proteins; Neurodegenerative Diseases; Parkinson Disease; Synucleins

Glial cytoplasmic inclusions (GCIs) are the histological hallmark of multiple system atrophy (MSA). In six postmortem brains of patients with MSA, 14-3-3-protein immunoreactivity was identified in GCIs predominately in the white matter tissue of the basal forebrain and cerebellum. Using double immunohistochemistry, co-localization of 14-3-3-protein and alpha-synuclein immunoreactivities in the GCIs was confirmed. The immunolabeling rate of GCIs with 14-3-3 proteins varied regionally from approximately 40% to 90%. Semiquantitative analysis yielded a significant negative correlation between degree of tissue degeneration and density of 14-3-3-protein-immunoreactive GCIs. The 14-3-3 proteins are active cofactors involved in cellular regulation through binding to phosphorylated motifs in target proteins and alpha-synuclein is a known target of 14-3-3. Our study suggests that 14-3-3 proteins are closely associated with alpha-synuclein in GCIs and 14-3-3 proteins may be candidate cofactors of alpha-synuclein in GCI formation.

Topics: 14-3-3 Proteins; Aged; Aged, 80 and over; alpha-Synuclein; Brain; Humans; Immunohistochemistry; Inclusion Bodies; Middle Aged; Multiple System Atrophy; Nerve Degeneration; Nerve Tissue Proteins; Neuroglia; Synucleins; Tyrosine 3-Monooxygenase

Multiple system atrophy (MSA) belongs to synucleinopathies and is characterized pathologically by oligodendroglial inclusions (GCIs) composed of 20- to 30-nm tubular filaments. alpha-Synuclein fibrils formed in vitro, however, range between 10 and 12 nm in diameter. To understand the relationship between alpha-synuclein and GCI filaments, we conducted structural analyses of GCIs in fixed brain sections and isolated from fresh-frozen MSA brains. In fixed brain sections, GCIs were composed of amorphous material-coated filaments up to 30 nm in size. The filaments were often organized in parallel bundles extending into oligodendroglial processes. In freshly isolated GCIs, progressive buffer washes removed amorphous material and revealed that GCI filaments consisted of 10-nm-sized central core fibrils that were strongly alpha-synuclein immunoreactive. Image analysis revealed that each core fibril was made of two subfibrils, and each subfibril was made of a string of 3- to 6-nm-sized particles probably alpha-synuclein oligomers. Immunogold labeling demonstrated that epitopes encompassing entire alpha-synuclein molecule were represented in the core fibrils, with the N-terminal 11-26 and C-terminal 108-131 amino acid residues most accessible to antibodies, probably exposed on the surface of the fibril. Our study indicates that GCI filaments are multilayered in structure, with alpha-synuclein oligomers forming the central core fibrils of the filaments.

Topics: Aged; alpha-Synuclein; Humans; Image Processing, Computer-Assisted; Inclusion Bodies; Microscopy, Immunoelectron; Middle Aged; Multiple System Atrophy; Nerve Tissue Proteins; Oligodendroglia; Synucleins

Multiple system atrophy (MSA) is a neurodegenerative disease characterized by the presence of glial cytoplasmic inclusions (GCIs), which are comprised of fibrils of the protein alpha-synuclein (alpha-syn). Increasing evidence indicate that the formation of these lesions leads to cellular dysfunction and degeneration. The events that result in the formation of GCIs remain poorly understood. It is possible that changes in the cytoplasmic milieu, perhaps the aberrant expression of alpha-syn-interacting proteins, can promote the polymerization of alpha-syn. The presence of the microtubule-binding protein, tau, in GCIs has been reported in some studies, but these findings have not been consistent, and these studies were performed prior to the availability of the more sensitive methods of detecting GCIs using anti-alpha-syn antibodies. Recently, 14-3-3 proteins, putative alpha-syn-interacting partners, have been reported in Lewy bodies, which also are pathological inclusions comprised of alpha-syn. In this study the presence of tau and 14-3-3 proteins in GCIs of 21 patients with MSA was investigated. For the majority of cases, tau and 14-3-3 proteins were detected only in a subset of GCIs. In some cases none of the GCIs contained 14-3-3 or tau. When present in GCIs, tau was in a hypophosphorylated state as demonstrated with phosphorylation-specific antibodies. Alpha-syn fibrillogenesis without 14-3-3 or tau appears to be sufficient for GCI formation, although it is possible that the accumulation of multi-functional proteins, like 14-3-3, in GCIs contribute to the disruption of cellular homeostasis.

Topics: 14-3-3 Proteins; Adult; Aged; alpha-Synuclein; Blotting, Western; Cell Line; Cerebellum; Cytoplasm; Embryo, Mammalian; Female; Humans; Immunohistochemistry; Kidney; Male; Middle Aged; Multiple System Atrophy; Nerve Tissue Proteins; Neuroglia; Pons; Synucleins; tau Proteins; Tyrosine 3-Monooxygenase

alpha-Synucleinopathies, including Parkinson's disease, dementia with Lewy bodies, and multiple system atrophy, are neurodegenerative disorders in which abnormal inclusions containing alpha-synuclein accumulate in selectively vulnerable neurons and glia. In this report, immunohistochemistry demonstrates ubiquitin in subsets of alpha-synuclein inclusions in dementia with Lewy bodies and multiple system atrophy. Biochemistry demonstrates that alpha-synuclein in the sodium dodecyl sulfate-soluble fractions of diseased brains is ubiquitinated, with mono- and di-ubiquitinated species predominating over polyubiquitinated forms. Similar immunohistochemical and biochemical characteristics were observed in an A53T mutant human alpha-synuclein transgenic mouse model of neurodegenerative alpha-synucleinopathies. Furthermore, in vitro ubiquitination of alpha-synuclein fibrils recapitulated the pattern of alpha-synuclein ubiquitination observed in human disease and the A53T alpha-synuclein mouse model. These results suggest that ubiquitination of alpha-synuclein is not required for inclusion formation and follows the fibrillization of alpha-synuclein.

Topics: Adult; Aged; Aged, 80 and over; alpha-Synuclein; Animals; Cell Fractionation; Disease Models, Animal; Female; Gyrus Cinguli; Humans; Inclusion Bodies; Lewy Body Disease; Male; Mice; Mice, Transgenic; Middle Aged; Multiple System Atrophy; Nerve Tissue Proteins; Spinal Cord; Synucleins; Ubiquitin

In many neurodegenerative diseases, the cytopathological hallmark is the presence of ubiquitylated inclusions consisting of insoluble protein aggregates. Lewy bodies in Parkinson's disease and dementia with Lewy bodies disease, glial cell inclusions in multiple system atrophy, and hyaline inclusions in amyotrophic lateral sclerosis (ALS) are representative of these inclusions. The elucidation of the components of these inclusions and the mechanisms underlying inclusion formation is important in uncovering the pathogenesis of these disorders. We hypothesized that Dorfin, a perinuclearly located E3 ubiquitin ligase, participates in the formation of ubiquitylated inclusions in a wide range of neurodegenerative diseases. Here, we report that affinity-purified anti-Dorfin antibody labeled ubiquitylated inclusions of Parkinson's disease, dementia with Lewy bodies disease, multiple system atrophy, and sporadic and familial ALS. A double-immunofluorescence study revealed that Dorfin shows a distribution pattern parallel to that of ubiquitin. Furthermore, by a filter trap assay, we detected that Dorfin is present in the ubiquitylated high-molecular weight structures derived from these diseases. These results suggest that Dorfin plays a crucial role in the formation of ubiquitylated inclusions of alpha-synucleinopathy and ALS. However, because we failed to show the direct binding of alpha-synuclein with Dorfin, future investigations into the binding partner(s) of Dorfin will be needed to deepen our understanding of the pathophysiology of alpha-synucleinopathy and ALS.

Topics: Aged; alpha-Synuclein; Amyotrophic Lateral Sclerosis; Antibodies; Cell Line; DNA-Binding Proteins; Female; Humans; Inclusion Bodies; Lewy Body Disease; Male; Middle Aged; Molecular Weight; Multiple System Atrophy; Nerve Tissue Proteins; Neuroglia; Neurons; Parkinson Disease; Protein Binding; Superoxide Dismutase; Superoxide Dismutase-1; Synucleins; Ubiquitin; Ubiquitin-Protein Ligases

Multiple system atrophy (MSA) is a sporadic neurodegenerative disorder that usually manifests in the early sixth decade of life and progresses relentlessly with a mean survival of 9 years. Clinically, MSA is dominated by autonomic/urogenital failure, which may be associated with either levodopa (L-dopa) -unresponsive parkinsonism in 80% of cases (MSA-P subtype) or with cerebellar ataxia in 20% of cases (MSA-C subtype). Pathologically, MSA is characterized by a neuronal multisystem degeneration and abnormal glial cytoplasmic inclusions containing alpha-synuclein aggregates. Pharmacological treatment of motor features is disappointing except for a transient L-dopa response in a minority of MSA-P patients. In contrast, autonomic and urogenital features of MSA should be identified early on, because they can be treated effectively in many instances. Neuroprotective strategies are presently unavailable, however, two multicentre European trials have been launched to evaluate the effects of riluzole and human recombinant growth hormone on disease progression in MSA. Clearly, further randomised, controlled trials are required to identify effective symptomatic or neuroprotective agents in MSA. Several in vivo models have become available to allow a careful preselection of candidate agents. Several research groups have been formed in Europe (EMSA-SG, NNIPPS) and United States (NAMSA-SG), providing a framework for coordinated trial activity in MSA.

Topics: alpha-Synuclein; Animals; Brain; Clinical Trials as Topic; Humans; Inclusion Bodies; Levodopa; Multiple System Atrophy; Nerve Tissue Proteins; Neurologic Examination; Neurons; Neuroprotective Agents; Parkinsonian Disorders; Synucleins

Alpha-synuclein has an important role in the pathogenesis of Parkinson disease (PD), dementia with Lewy bodies (DLB), and multiple system atrophy (MSA), comprising a new disease concept, that of alpha-synucleinopathies. Cerebellar degeneration with Purkinje cell depletion is present in the majority of MSA cases. By contrast, cerebellar pathology has not been demonstrated unequivocally in either PD or DLB. Recent immunohistochemical studies using anti-alpha-synuclein antibodies have shown that LB-type degeneration in PD and DLB is more widespread than previously recognized. To determine whether cerebellar Purkinje cells might be involved in alpha-synuclein pathology, we carried out immunohistochemical examinations of the cerebella of patients with PD (n = 10), DLB (n = 7), MSA (n = 10), Alzheimer disease and other tauopathies (n = 9), and age-matched control subjects (n = 10), using antibodies specific for alpha-synuclein. Although no abnormal accumulation of alpha-synuclein was noted in the Purkinje cell somata, numerous alpha-synuclein-positive, round inclusions were found in the cerebellar white matter in all the patients with PD and DLB. Immunohistochemical and ultrastructural examinations revealed that the majority of these inclusions was located in the Purkinje cell axons and consisted of granulo-filamentous structures. No such inclusions were observed in MSA, tauopathies, or controls. These findings indicate that Purkinje cells are also the victims of a-synuclein pathology in PD and DLB, but not in MSA.

Topics: Aged; Aged, 80 and over; alpha-Synuclein; Calbindins; Cell Count; Cerebellum; Cerebral Cortex; Female; Humans; Immunohistochemistry; Lewy Body Disease; Male; Microscopy, Immunoelectron; Middle Aged; Multiple System Atrophy; Nerve Tissue Proteins; Neurites; Parkinson Disease; Purkinje Cells; S100 Calcium Binding Protein G; Synucleins

Alpha-Synuclein is a major component of neuronal and glial cytoplasmic inclusions in multiple system atrophy (MSA), one of the alpha-synucleinopathies. Recent studies have shown that beta-synuclein, a homolog of alpha-synuclein, inhibits alpha-synuclein aggregation in vitro. We immunohistochemically examined the MSA brain, using specific antibodies against alpha-synuclein and beta-synuclein. alpha-synuclein-positive filamentous aggregates were frequently found in neurons in the pontine and inferior olivary nuclei. No abnormal accumulation of alpha-synuclein was noted in Purkinje cells. In contrast, beta-synuclein accumulation occurred extensively in Purkinje cells, and only minimally in pontine and olivary neurons. Thus, neuronal alpha-synuclein inclusions appear to occur only rarely in neurons in which beta-synuclein accumulates. These findings support the possibility that beta-synuclein is a negative regulator of alpha-synuclein aggregation.

Topics: Aged; alpha-Synuclein; beta-Synuclein; Brain; Case-Control Studies; Cytoplasm; Humans; Immunohistochemistry; Male; Middle Aged; Multiple System Atrophy; Nerve Tissue Proteins; Neuroglia; Neurons; Purkinje Cells; Synucleins

Accumulation of alpha-synuclein has been associated with neurodegenerative disorders, such as Lewy body disease and multiple system atrophy. We previously showed that expression of wild-type human alpha-synuclein in transgenic mice results in motor and dopaminergic deficits associated with inclusion formation. To determine whether different levels of human alpha-synuclein expression from distinct promoters might result in neuropathology mimicking other synucleopathies, we compared patterns of human alpha-synuclein accumulation in the brains of transgenic mice expressing this molecule from the murine Thy-1 and platelet-derived growth factor (PDGF) promoters. In murine Thy-1-human alpha-synuclein transgenic mice, this protein accumulated in synapses and neurons throughout the brain, including the thalamus, basal ganglia, substantia nigra, and brainstem. Expression of human alpha-synuclein from the PDGF promoter resulted in accumulation in synapses of the neocortex, limbic system, and olfactory regions as well as formation of inclusion bodies in neurons in deeper layers of the neocortex. Furthermore, one of the intermediate expressor lines (line M) displayed human alpha-synuclein expression in glial cells mimicking some features of multiple system atrophy. These results show a more widespread accumulation of human alpha-synuclein in transgenic mouse brains. Taken together, these studies support the contention that human alpha-synuclein expression in transgenic mice might mimic some neuropathological alterations observed in Lewy body disease and other synucleopathies, such as multiple system atrophy.

Topics: alpha-Synuclein; Animals; Gene Expression; Humans; Lewy Body Disease; Limbic System; Mice; Mice, Transgenic; Multiple System Atrophy; Neocortex; Nerve Tissue Proteins; Neuroglia; Neurons; Platelet-Derived Growth Factor; Promoter Regions, Genetic; Substantia Nigra; Synucleins; Thy-1 Antigens

alpha-Synuclein normally a synaptic vesicle-associated cytoplasmic protein is the major component of filamentous inclusions of neurons in Parkinson's disease and dementia with Lewy bodies. It is also the major component of glial inclusions of multiple system atrophy. In characterizing cells derived from embryonic neural stem cells we found all oligodendrocytes had strong cytoplasmic expression of alpha-synuclein. Comparison of cells from presenilin 1 (PS1)-deficient mice with wild type revealed a 7-fold increase in oligodendrocytes. Western blotting analysis indicated the cells contained alpha-synuclein monomers and SDS-stable dimers and trimers. This cell system of oligodendroglial alpha-synuclein expression is a useful system to study alpha-synuclein metabolism in the cell type affected in multiple system atrophy. Increased oligodendroglial cell numbers from PS1-deficient cells provides further evidence for a role of PS1-dependent Notch signalling in cell fate decisions.

Topics: alpha-Synuclein; Animals; Blotting, Western; Cell Count; Cell Differentiation; Cells, Cultured; Gene Expression; Inclusion Bodies; Membrane Proteins; Mice; Mice, Mutant Strains; Multiple System Atrophy; Nerve Tissue Proteins; Oligodendroglia; Presenilin-1; Stem Cells; Synucleins

Clusterin/apolipoprotein J protein expression in cases with "alpha-synucleinopathies", such as Parkinson's disease (PD), dementia with Lewy bodies (DLB) and multiple system atrophy (MSA), was investigated using an immunohistochemical method for the labeling of multiple antigens. About 50% of the cortical Lewy bodies in the cases with DLB were immunoreactive for clusterin, whereas brain-stem Lewy bodies in PD and DLB were rarely associated with clusterin. Clusterin was also immunopositive in around 10% of the glial cytoplasmic inclusions (GCIs) in the cases with MSA. Colocalization of clusterin with alpha-synuclein in such bodies or inclusions was clearly correlated with the immunostaining pattern of alpha-synuclein. Subcellular localization of clusterin was almost completely overlapped with the homogeneous immunoreaction of alpha-synuclein in the cortical Lewy bodies; however, clusterin immunoreactivity was not detected in the halo or ring-like structures of the brain-stem Lewy bodies. Furthermore, some Lewy bodies with intense immunoreactivity for clusterin showed only a weak signal for alpha-synuclein. These results suggest that clusterin may modify the formation of alpha-synuclein-positive inclusion bodies such as Lewy bodies and GCIs, through a previously proposed chaperone property of clusterin.

Topics: alpha-Synuclein; Alzheimer Disease; Apolipoproteins E; Brain; Clusterin; Glycoproteins; Humans; Immunohistochemistry; Inclusion Bodies; Lewy Bodies; Lewy Body Disease; Molecular Chaperones; Multiple System Atrophy; Nerve Tissue Proteins; Neurofibrillary Tangles; Neuroglia; Parkinson Disease; Peptide Fragments; Pick Disease of the Brain; Supranuclear Palsy, Progressive; Synucleins

We had previously reported that systemic overexpression of the alpha(1B)-adrenergic receptor (AR) in a transgenic mouse induced a neurodegenerative disease that resembled the parkinsonian-like syndrome called multiple system atrophy (MSA). We now report that our mouse model has cytoplasmic inclusion bodies that colocalize with oligodendrocytes and neurons, are positive for alpha-synuclein and ubiquitin, and therefore may be classified as a synucleinopathy. Alpha-synuclein monomers as well as multimers were present in brain extracts from both normal and transgenic mice. However, similar to human MSA and other synucleinopathies, transgenic mice showed an increase in abnormal aggregated forms of alpha-synuclein, which also increased its nitrated content with age. However, the same extracts displayed decreased phosphorylation of alpha-synuclein. Other traits particular to MSA such as Purkinje cell loss in the cerebellum and degeneration of the intermediolateral cell columns of the spinal cord also exist in our mouse model but differences still exist between them. Interestingly, long-term therapy with the alpha(1)-AR antagonist, terazosin, resulted in protection against the symptomatic as well as the neurodegeneration and alpha-synuclein inclusion body formation, suggesting that signaling of the alpha(1B)-AR is the cause of the pathology. We conclude that overexpression of the alpha(1B)-AR can cause a synucleinopathy similar to other parkinsonian syndromes.

Topics: Adrenergic alpha-Antagonists; alpha-Synuclein; Animals; Body Weight; Brain; Cerebellum; Disease Models, Animal; Female; Inclusion Bodies; Macromolecular Substances; Male; Mice; Mice, Transgenic; Motor Activity; Multiple System Atrophy; Nerve Tissue Proteins; Neurodegenerative Diseases; Neurons; Nitrates; Oligodendroglia; Phosphorylation; Prazosin; Receptors, Adrenergic, alpha-1; Spinal Cord; Survival Rate; Synucleins; Tyrosine; Ubiquitin

We report the histopathological and immunohistochemical findings from the brain of an elderly patient diagnosed with Parkinson's disease (PD). Neuropathological examination revealed moderate neuronal cell loss and astrocytosis in the substantia nigra. Lewy bodies were found in many sites characteristic for PD, including the substantia nigra, locus coeruleus, hypothalamus, substantia innominata, pontine raphe nucleus, and dorsal motor vagal nucleus, cingulate and insular cortices. Furthermore, argyrophilic glial intracytoplasmic inclusions were found predominantly in the ventral pons, cerebellar white matter, precentral and frontal white matter, internal and external capsule, claustrum, and putamen. Inclusions were triangular in shape, and immunopositive for ubiquitin and alpha-synuclein. In view of these histopathological and immunohistochemical findings and patterns of distribution, the inclusions were suggested to be glial cytoplasmic inclusions (GCIs) in multiple system atrophy (MSA). These findings suggested that our case might have experienced two pathological processes; PD and the early stage of MSA (striatonigral degeneration) that had not progressed to striatal involvement. Alternatively a common pathological background including abnormal processing of alpha-synuclein could contribute to widespread accumulation of Lewy bodies and GCIs in a single condition accompanied by nigral degeneration.

Topics: Aged; alpha-Synuclein; Brain; Humans; Immunohistochemistry; Lewy Bodies; Male; Multiple System Atrophy; Nerve Tissue Proteins; Neuroglia; Parkinson Disease; Synucleins; Ubiquitin

To understand the possible pathogenesis of sporadic multiple system atrophy (MSA).. The immunoreactivity and ultrastructural features of glial cytoplasmic inclusions (GCIs) in 12 autopsy patients with MSA and 4 normal control groups were studied. All regional sections from each subject were evaluated with HE staining, Klüver-Barrera (KB), Holzer's, modified Gallyas-Braak's (GB) methods and immunohistochemical staining with alpha-synuclein and ubiquitin antibodies. Pontine white matter with abundant GCIs from case 1 was examined, using conventional electron microscopy, Gallyas-Braak's electron microscopy and immunoelectron microscopy.. The presence of GCIs as constantly demonstrated in all MSA patients. Strong alpha-synuclein immunoreactivity was observed in all of the ubiquitinated GCIs. However, the density of alpha-synuclein positive GCIs differed from case to case, and there was no relationship between the density of GCIs and age, sex, or MSA subtype. Ultrastructural features indicated that argyrophilic granule-associated filaments of about 25 nm in diameter were the predominant constituents of GCIs, and the anti alpha-synuclein antibody selectively labeled in these filaments. No GCIs and alpha-synuclein immunoreaction were found in control brain tissues.. GCI was a pathognomonic change in sporadic MSA patients. Accumulation of alpha-synuclein in GCIs may occur during the early stags of MSA. Seletcive alpha-synuclein positive abnormal microtubules in GCIs therefore play an important role in the pathogenesis of MSA.

Topics: Aged; Aged, 80 and over; alpha-Synuclein; Female; Humans; Immunohistochemistry; Inclusion Bodies; Male; Microscopy, Immunoelectron; Middle Aged; Multiple System Atrophy; Nerve Tissue Proteins; Neuroglia; Synucleins

We report a patient who showed pathological features of both multiple system atrophy (MSA) and progressive supranuclear palsy (PSP) at autopsy. The clinical features included severe cerebellar ataxia, autonomic failure, and rigid-akinetic parkinsonism. The clinical diagnosis was MSA. Pathological examination showed severe neuronal loss with gliosis in the putamen, substantia nigra, inferior olive, and the pontine nucleus, and numerous glial cytoplasmic inclusions. In addition, moderate neuronal loss with gliosis was observed in the globus pallidus and subthalamic nucleus, and neurofibrillary tangles and tufted astrocytes were seen in the basal ganglia and the brain stem. These findings indicate that the patient had both MSA and PSP. Double-labeling immunofluorescence in the brain stem showed alpha-synuclein immunoreactivity localized in the oligodendrocytes and phosphorylated tau immunoreactivity in the neurons and the glia. Co-existence of synucleinopathy and tauopathy is rare.

Topics: Aged; alpha-Synuclein; Brain; Brain Chemistry; Fatal Outcome; Humans; Immunohistochemistry; Male; Multiple System Atrophy; Nerve Tissue Proteins; Supranuclear Palsy, Progressive; Synucleins; tau Proteins

The inferior olivary nucleus (ION) from nine patients with multiple system atrophy was examined with antibodies against alpha-synuclein, ubiquitin, synaptophysin, glial fibrillary acidic protein, the Golgi apparatus (GA)-trans-Golgi network (TGN), and microglia/macrophages. As previously reported, there were neuronal loss, gliosis, and alpha-synuclein-positive cytoplasmic inclusions in neurons and glia. In addition, all neurons with alpha-synuclein-positive cytoplasmic inclusions contained abnormal profiles of the GA and TGN, which were reduced in size and numbers. This finding suggests a relationship between the pathogenetic mechanisms causing inclusion body formation and abnormalities of the GA-TGN. This study is also consistent with the conclusion that lesions of the ION may not always reflect changes of transsynaptic degeneration secondary to Purkinje cell loss.

Topics: Aged; alpha-Synuclein; Female; Glial Fibrillary Acidic Protein; Glycoproteins; Golgi Apparatus; Humans; Immunohistochemistry; Inclusion Bodies; Male; Medulla Oblongata; Membrane Glycoproteins; Membrane Proteins; Middle Aged; Multiple System Atrophy; Nerve Tissue Proteins; Neurons; Olivary Nucleus; Receptors, Cell Surface; Receptors, Fibroblast Growth Factor; Retrograde Degeneration; Sialoglycoproteins; Synaptophysin; Synucleins; Ubiquitin

(Oligodendro)glial cytoplasmic inclusions composed of alpha-synuclein (alpha SYN) characterize multiple system atrophy (MSA). Mature oligodendrocytes (OLs) do not normally express alpha SYN, so MSA pathology may arise from aberrant expression of alpha SYN in OLs. To study pathological deposition of alpha SYN in OLs, transgenic mice were generated in which human wild-type alpha SYN was driven by a proteolipid protein promoter. Transgenic alpha SYN was detected in OLs but no other brain cell type. At the light microscopic level, the transgenic alpha SYN profiles resembled glial cytoplasmic inclusions. Strikingly, the diagnostic hyperphosphorylation at S129 of alpha SYN was reproduced in the transgenic mice. A significant proportion of the transgenic alpha SYN was detergent insoluble, as in MSA patients. The histological and biochemical abnormalities were specific for the disease-relevant alpha SYN because control green fluorescent protein was fully soluble and evenly distributed throughout OL cell bodies and processes. Thus, ectopic expression alpha SYN in OLs might initiate salient features of MSA pathology.

Topics: alpha-Synuclein; Animals; Brain; Humans; Mice; Mice, Transgenic; Microscopy, Confocal; Multiple System Atrophy; Nerve Tissue Proteins; Oligodendroglia; Phosphorylation; Solubility; Synucleins

Intracellular inclusions containing alpha-synuclein (alpha SN) are pathognomonic features of several neurodegenerative disorders. Inclusions occur in oligodendrocytes in multiple system atrophy (MSA) and in neurons in dementia with Lewy bodies (DLB) and Parkinson's disease (PD). In order to identify disease-associated changes of alpha SN, this study compared the levels, solubility and molecular weight species of alpha SN in brain homogenates from MSA, DLB, PD and normal aged controls. In DLB and PD, substantial amounts of detergent-soluble and detergent-insoluble alpha SN were detected compared with controls in grey matter homogenate. Compared with controls, MSA cases had significantly higher levels of alpha SN in the detergent-soluble fraction of brain samples from pons and white matter but detergent-insoluble alpha SN was not detected. There was an inverse correlation between buffered saline-soluble and detergent-soluble levels of alpha SN in individual MSA cases suggesting a transition towards insolubility in disease. The differences in solubility of alpha SN between grey and white matter in disease may result from different processing of alpha SN in neurons compared with oligodendrocytes. Highly insoluble alpha SN is not involved in the pathogenesis of MSA. It is therefore possible that buffered saline-soluble or detergent-soluble forms of alpha SN are involved in the pathogenesis of other alpha SN-related diseases.

Topics: Aged; alpha-Synuclein; Blotting, Western; Brain Chemistry; Cerebellum; Electrophoresis, Polyacrylamide Gel; Frontal Lobe; Humans; Lewy Body Disease; Middle Aged; Molecular Weight; Multiple System Atrophy; Myelin Sheath; Nerve Tissue Proteins; Neurons; Oligodendroglia; Parkinson Disease; Pons; Reference Values; Sodium Dodecyl Sulfate; Solubility; Synucleins

alpha-Synuclein has been identified as a component of Lewy bodies in Parkinson's disease and diffuse Lewy body disease, and glial cytoplasmic inclusions (GCIs) in multiple system atrophy (MSA). To explore the role of alpha-synuclein in the pathogenesis, we searched for molecules interacting with alpha-synuclein and discovered that GCIs are stained by anti-Elk-1 antibody. To seek the role of Elk-1 in synucleinopathies, we cotransfected alpha-synuclein and Elk-1 to cultured cells, and found small granular structure complexes where the two molecules colocalized. Moreover, alpha-synuclein and Elk-1 were co-immunoprecipitated from the cell lysates. For formation of the complex, the presence of both ETS and B-box domains of Elk-1 was required. Although there was no evidence of direct binding between alpha-synuclein and Elk-1, we discovered that alpha-synuclein and Elk-1 both bind to ERK-2, a MAP kinase. The effect of alpha-synuclein on the MAP kinase pathway was assessed using the Pathdetect system, which showed prominent attenuation of Elk-1 phosphorylation with alpha-synuclein, and especially A53T mutant. Our results suggest that alpha-synuclein reacts with the MAP kinase pathway, which might cause dysfunction of neurons and oligodendrocytes and lead to neurodegeneration in Parkinson's disease and MSA.

Topics: alpha-Synuclein; Amino Acid Motifs; Animals; Binding Sites; Cell Line; Cytoplasmic Granules; DNA-Binding Proteins; ets-Domain Protein Elk-1; Humans; Lewy Body Disease; Macromolecular Substances; MAP Kinase Signaling System; Mice; Mitogen-Activated Protein Kinase 1; Multiple System Atrophy; Mutagenesis, Site-Directed; Nerve Tissue Proteins; Neuroglia; Neurons; Parkinson Disease; Phosphorylation; Precipitin Tests; Protein Binding; Protein Structure, Tertiary; Proto-Oncogene Proteins; Synucleins; Transcription Factors; Transfection

Neuronal and glial cytoplasmic inclusions (NCIs and GCIs), which contain alpha-synuclein as a major component, are characteristic cytopathological features of multiple system atrophy (MSA). We report MSA of 19 years' duration in a 73-year-old woman. Her initial symptom was parkinsonism, with dementia appearing about 8 years later. Postmortem examination showed marked atrophy of the frontal and temporal white matter and limbic system, in addition to the pathology typical of MSA. In the limbic system, severe neuronal loss and astrocytosis were observed, and the remaining neurons often had lightly eosinophilic, spherical cytoplasmic inclusions. Interestingly, a double-labeling immunofluorescence study revealed that the NCIs in the dentate gyrus and amygdaloid nucleus, and the GCIs in the frontal and temporal white matter often expressed both alpha-synuclein NACP-5 and phosphorylated tau AT8 epitopes. Double-immunolabeling electron microscopy of the NCIs in the dentate gyrus and the GCIs in the temporal white matter clearly revealed labeling of their constituent granule-associated filaments with NACP-5, and some of them were also labeled with AT8. These findings strongly suggested that some alpha-synuclein filaments were decorated with phosphorylated tau without formation of fibrils such as paired helical filaments. Immunoblotting of sarkosyl-insoluble tau indicated that the accumulated tau consisted mainly of four-repeat tau isoforms of 383 amino acids and 412 amino acids. We consider that the limbic system can be a major site of neurodegeneration in MSA of long duration. The mechanisms of such abnormal tau accumulation in the NCIs and GCIs are unknown.

Topics: Aged; alpha-Synuclein; Brain; Cytoplasm; Female; Gliosis; Humans; Immunoblotting; Immunohistochemistry; Inclusion Bodies; Microscopy, Electron; Multiple System Atrophy; Nerve Degeneration; Nerve Tissue Proteins; Neuroglia; Neurons; Phosphorylation; Protein Isoforms; Protein Structure, Tertiary; Sarcosine; Solubility; Synucleins; tau Proteins

The human arcuate nucleus (ArcN) has been considered akin to the pontine precerebellar nuclei. However, there is anatomical, functional, and clinical evidence that the ArcN may be the homologue of chemosensitive areas of the ventral medullary surface involved in ventilatory responses to hypercarbia and cerebrospinal fluid acidosis. Acetylcholine has been involved in mechanisms of central chemosensitivity. Loss of ArcN neurons has been reported in patients with multiple system atrophy (MSA), a disorder characterized by disturbed automatic ventilation, but the neurochemical identity of these neurons is undetermined. We sought to determine whether the ArcN contains cholinergic neurons and whether these neurons are depleted in patients with MSA. Medullae were obtained from six patients with MSA, five patients with Parkinson's disease (PD) and six sex- and age-matched controls. Fifty-micron transverse sections obtained through the mid-olivary levels were processed for acetylcholinesterase (AchE), choline acetyltransferase (CAT), and alpha-synuclein immunoreactivity. We found that the ArcN contained CAT-positive neurons. There was a significant decrease in density of cholinergic ArcN neurons in MSA but not in PD patients. alpha-Synuclein-containing inclusions were present in the ArcN of MSA patients. Depletion of cholinergic neurons may provide a substrate for disturbances in automatic respiration in MSA patients.

Topics: Aged; Aged, 80 and over; alpha-Synuclein; Arcuate Nucleus of Hypothalamus; Choline O-Acetyltransferase; Cholinergic Fibers; Female; Humans; Inclusion Bodies; Male; Middle Aged; Multiple System Atrophy; Nerve Tissue Proteins; Neurons; Sleep Apnea Syndromes; Synucleins

To determine whether multiple system atrophy (MSA) is associated with altered expression levels of the alpha-synuclein messenger RNA (mRNA), we performed quantitative reverse transcription polymerase chain reaction for alpha-synuclein mRNA using postmortem brain samples from 11 cases of MSA and 14 age-matched control subjects. The brain specimens used in this study contained both the gray matter and white matter, which were dissected from the frontal, temporal or occipital lobe. The expression levels of alpha-synuclein mRNA in the brain specimens of MSA cases were not different from those of the control subjects. These results suggest that the transcriptional regulation of the alpha-synuclein gene is unlikely to be affected in MSA brains.

Topics: Aged; alpha-Synuclein; Cerebral Cortex; Humans; Middle Aged; Multiple System Atrophy; Nerve Fibers, Myelinated; Nerve Tissue Proteins; Neurons; Oligodendroglia; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Synucleins

The defining neuropathological deposits of Parkinson's disease, dementia with Lewy bodies and multiple system atrophy are strongly immunoreactive for alpha-synuclein. We have shown previously that isolated filaments from dementia with Lewy bodies and multiple system atrophy brains are labelled in a characteristic fashion by a number of alpha-synuclein antibodies. Here we have extracted filaments from substantia nigra of patients with idiopathic Parkinson's disease. Antibodies directed against the carboxy-terminal region of alpha-synuclein labelled isolated filaments along their entire lengths. By contrast, an antibody directed against the amino-terminal region of alpha-synuclein only labelled one filament end. These characteristics were identical to those of filaments extracted from brains of patients with dementia with Lewy bodies and multiple system atrophy.

Topics: Aged; Aged, 80 and over; alpha-Synuclein; Antibodies; Cytoskeleton; Humans; Lewy Body Disease; Microscopy, Electron; Multiple System Atrophy; Nerve Tissue Proteins; Parkinson Disease; Substantia Nigra; Synucleins

Although alpha-synuclein (alpha-syn) has been implicated as a major component of the abnormal filaments that form glial cytoplasmic inclusions (GCIs) in multiple system atrophy (MSA), it is uncertain if GCIs are homogenous and contain full-length alpha-syn. Since this has implications for hypotheses about the pathogenesis of GCIs, we used a novel panel of antibodies to defined regions throughout alpha-syn in immunohistochemical epitope mapping studies of GCIs in MSA brains. Although the immunostaining profile of GCIs with these antibodies was similar for all MSA brains, there were significant differences in the immunoreactivity of the alpha-syn epitopes detected in GCIs. Notably, carboxy-terminal alpha-syn epitopes were immunodominant in GCIs, but the entire panel of antibodies immunostained cortical Lewy bodies (LBs) in dementia with LBs brain with similar intensity. While the distribution of alpha-syn labeled GCIs paralleled that previously reported using silver stains, antibodies to carboxy-terminal alpha-syn epitopes revealed a previously undescribed burden of GCIs in the MSA hippocampal formation. Finally, Western blots demonstrated detergent insoluble monomeric and high-molecular weight alpha-syn species in GCI rich MSA cerebellar white matter. Collectively, these data indicate that alpha-syn is a prominent component of GCIs in MSA, and that GCIs and LBs may result from cell type specific conformational or post-translational permutations in alpha-syn.

Topics: Aged; Aged, 80 and over; alpha-Synuclein; Antibodies; Antibodies, Monoclonal; Basal Ganglia; Brain; Cerebellum; Female; Hippocampus; Humans; Immunohistochemistry; Male; Medulla Oblongata; Mesencephalon; Middle Aged; Multiple System Atrophy; Nerve Tissue Proteins; Pons; Synucleins

Aggregated alpha-synuclein proteins form brain lesions that are hallmarks of neurodegenerative synucleinopathies, and oxidative stress has been implicated in the pathogenesis of some of these disorders. Using antibodies to specific nitrated tyrosine residues in alpha-synuclein, we demonstrate extensive and widespread accumulations of nitrated alpha-synuclein in the signature inclusions of Parkinson's disease, dementia with Lewy bodies, the Lewy body variant of Alzheimer's disease, and multiple system atrophy brains. We also show that nitrated alpha-synuclein is present in the major filamentous building blocks of these inclusions, as well as in the insoluble fractions of affected brain regions of synucleinopathies. The selective and specific nitration of alpha-synuclein in these disorders provides evidence to directly link oxidative and nitrative damage to the onset and progression of neurodegenerative synucleinopathies.

Topics: alpha-Synuclein; Alzheimer Disease; Antibodies, Monoclonal; Blotting, Western; Brain; Brain Chemistry; Enzyme-Linked Immunosorbent Assay; Fluorescent Antibody Technique; Humans; Immunohistochemistry; Lewy Bodies; Lewy Body Disease; Microscopy, Immunoelectron; Multiple System Atrophy; Nerve Tissue Proteins; Neurodegenerative Diseases; Neurons; Oxidative Stress; Parkinson Disease; Synucleins; Tyrosine

Article abstract-Alpha synuclein, tau, synphilin, and APOE genotypes were analyzed in patients with multiple system atrophy (MSA) and progressive supranuclear palsy (PSP) and controls. The predisposing effect of the tau insertion polymorphism to the development of PSP is confirmed. However, no effect of alpha-synuclein, synphilin, or APOE variability on the development of PSP, or of tau, alpha-synuclein, APOE, or synphilin gene variability on the development of MSA, are demonstrated.

Topics: alpha-Synuclein; Apolipoproteins E; Carrier Proteins; Genotype; Humans; Multiple System Atrophy; Nerve Tissue Proteins; Polymorphism, Genetic; Supranuclear Palsy, Progressive; Synucleins; tau Proteins

To determine whether mutations in the coding region of the alpha-synuclein gene are relevant in cases of multiple system atrophy (MSA), detailed nucleotide sequence analysis of the alpha-synuclein gene was performed using total RNA obtained from autopsied brain specimens of 11 pathologically confirmed cases of MSA. The brain specimens used in this study contained both gray and white matter, which were dissected from the frontal, temporal or occipital lobe. No nucleotide alterations were found in the entire coding region of the alpha-synuclein gene in any of the cases. While mutations in the regulatory or intronic regions of the gene were not ruled out, our results suggest that mutations in the coding region of the alpha-synuclein gene are unlikely to contribute to the pathogenesis of MSA.

Topics: Aged; Aged, 80 and over; alpha-Synuclein; Base Sequence; Cadaver; Humans; Middle Aged; Molecular Sequence Data; Multiple System Atrophy; Mutation; Nerve Tissue Proteins; Reverse Transcriptase Polymerase Chain Reaction; RNA; Synucleins

Glial cytoplasmic inclusions (GCI) are the hallmark of multiple system atrophy (MSA), a rare movement disorder frequently associated with autonomic dysfunction. In this study of 21 cases of MSA, GCI were consistently immunoreactive for alpha-synuclein and double-immunostained for ubiquitin and oligodendroglial markers, but not glial fibrillary acidic protein. No statistically significant difference was found in the density of GCI in various brain regions in the two forms of MSA, striatonigral degeneration (SND) and olivopontocerebellar atrophy (OPCA). Postmortem brain samples from 9 cases of MSA were fractionated according to solubility in buffer, Triton-X 100, sodium dodecyl sulfate (SDS), and formic acid, and alpha-synuclein immunoreactivity was measured in Western blots. Total alpha-synuclein immunoreactivity was increased in MSA compared to controls, with no statistically significant difference between SND and OPCA. Most of the increase was due to alpha-synuclein in SDS fractions. In controls this fraction had little or no immunoreactivity. In 7 cases and 4 controls correlations were investigated between quantitative neuropathology and biochemical properties of alpha-synuclein. Surprisingly, the amount of SDS-soluble alpha-synuclein correlated poorly with the number of GCI in adjacent sections. Furthermore, areas with few or no GCI unexpectedly had abundant SDS-soluble alpha-synuclein. These findings provide evidence that modifications of alpha-synuclein in MSA may be more widespread than obvious histopathology. Moreover, these alterations may constitute a biochemical signature for the synucleinopathies.

Topics: Aged; Aged, 80 and over; alpha-Synuclein; Antibody Specificity; Antigens, Differentiation; Basal Ganglia; Brain; Cell Compartmentation; Female; Humans; Immunoblotting; Immunohistochemistry; Inclusion Bodies; Male; Middle Aged; Multiple System Atrophy; Nerve Tissue Proteins; Neuroglia; Putamen; Subcellular Fractions; Synucleins; Tissue Distribution; Ubiquitins

Immunohistochemical studies have shown that oligodendroglial inclusions in multiple system atrophy contain alpha-synuclein, a synaptic protein also found in Lewy bodies in Parkinson's disease. We have now used density gradient enrichment and an anti-alpha-synuclein immunomagnetic technique to isolate pure and morphologically intact oligodendroglial inclusions from brain white matter of patients dying with multiple system atrophy. Filamentous inclusion structures were obtained only from multiple system atrophy tissue, but not from normal brain tissues, or from multiple system atrophy tissue processed without anti-alpha-synuclein antibody. We confirmed the purity and morphology of isolated inclusions by electron microscopy. The inclusions comprised multiple protein bands after separation by polyacrylamide gel electrophoresis. Immunoblotting demonstrated that these proteins included alpha-synuclein, alphaB-crystallin, tubulins, ubiquitin, and prominent, possibly truncated alpha-synuclein species as high-molecular-weight aggregates. Our study provides the first biochemical evidence that oligodendroglial inclusion filaments consist of multiple protein components, suggesting that these inclusions may form as a result of multiprotein interactions with alpha-synuclein.

Topics: Aged; alpha-Synuclein; Biotinylation; Brain; Cell Fractionation; Centrifugation, Density Gradient; Crystallins; Female; Humans; Immunoblotting; Immunomagnetic Separation; Inclusion Bodies; Microscopy, Electron; Middle Aged; Multiple System Atrophy; Nerve Tissue Proteins; Neuroglia; Synucleins; Tubulin; Ubiquitins

A family of homologous proteins known as alpha-, beta-, and gamma-synuclein are abundantly expressed in brain, especially in the presynaptic terminal of neurons. Although the precise function of these proteins remains unknown, alpha-synuclein has been implicated in synaptic plasticity associated with avian song learning as well as in the pathogenesis of Parkinson's disease (PD), dementia with LBs (DLB), some forms of Alzheimer's disease (AD), and multiple system atrophy (MSA). Since olfactory dysfunction is a common feature of these disorders and the olfactory receptor neurons (ORNs) of the olfactory epithelium (OE) regenerate throughout the lifespan, we used antibodies specific for alpha-, beta-, and gamma-synucleins to examine the olfactory mucosa of patients with PD, DLB, AD, MSA, and controls without a neurological disorder. Although antibodies to alpha- and beta-synucleins detected abnormal dystrophic neurites in the OE of patients with neurodegenerative disorders, similar pathology was also seen in the OE of controls. More significantly, we show here for the first time that alpha-, beta-, and gamma-synucleins are differentially expressed in cells of the OE and respiratory epithelium and that alpha-synuclein is the most abundant synuclein in the olfactory mucosa, where it is prominently expressed in ORNs. Moreover, alpha- and gamma-synucleins also were prominent in the OE basal cells, which include the progenitor cells of the ORNs in the OE. Thus, our data on synuclein expression within the OE may signify that synuclein plays a role in the regeneration and plasticity of ORNs in the adult human OE.

Topics: Adult; Aged; Aged, 80 and over; alpha-Synuclein; Alzheimer Disease; Female; gamma-Synuclein; Humans; Immunohistochemistry; Male; Middle Aged; Multiple System Atrophy; Nerve Tissue Proteins; Neurodegenerative Diseases; Olfactory Mucosa; Parkinson Disease; Phosphoproteins; Synucleins

Lewy bodies in Parkinson' s disease (PD) are strongly immunoreactive with antibodies against alpha-synuclein, which is mutated in some familial cases of the disease. We carried out immunohistochemical examinations of the brains of multiple system atrophy (MSA) patients using anti-alpha-synuclein antibodies. Strong alpha-synuclein immunoreactivity was found in glial cytoplasmic inclusions (GCIs), which are of oligodendroglial origin and occur exclusively in MSA. Alpha-synuclein-immunoreactive neuronal cytoplasmic inclusions (NCIs) were also found occasionally in the substantia nigra, pontine and inferior olivary nuclei, and dentate fascia. These findings indicate that alpha-synuclein is also a major component of GCIs and NCIs in MSA and strongly suggest that alpha-synuclein aggregation is a common process in certain neurodegenerative diseases, including PD and MSA.

Topics: Aged; Aged, 80 and over; alpha-Synuclein; Brain; Brain Stem; Cerebellum; Humans; Immunohistochemistry; Lewy Bodies; Middle Aged; Multiple System Atrophy; Nerve Tissue Proteins; Neuroglia; Synucleins; Ubiquitins

Topics: alpha-Synuclein; Brain Stem; Coloring Agents; Dementia; Humans; Inclusion Bodies; Lewy Bodies; Motor Neuron Disease; Multiple System Atrophy; Nerve Tissue Proteins; Neurites; Neuroglia; Neurons; Parkinson Disease; Phosphoproteins; Silver; Synucleins

Alpha-synuclein forms the major component of Lewy bodies and Lewy neurites, the defining neuropathological characteristics of Parkinson's disease and dementia with Lewy bodies. Here we show that alpha-synuclein is also the major component of the filamentous inclusions of multiple system atrophy which comprises several neurodegenerative diseases with a shared filamentous pathology in nerve cells and glial cells. These findings provide an unexpected link between multiple system atrophy and Lewy body disorders and establish that alpha-synucleinopathies constitute a major class of human neurodegenerative disorder.

Topics: Adult; Aged; Aged, 80 and over; alpha-Synuclein; Cerebellum; Dementia; Frontal Lobe; Humans; Immunohistochemistry; Lewy Bodies; Middle Aged; Multiple System Atrophy; Nerve Tissue Proteins; Parkinson Disease; Pons; Synucleins

Recently, alpha-synuclein was shown to be a structural component of the filaments in Lewy bodies (LBs) of Parkinson's disease (PD), dementia with LBs (DLB) as well as the LB variant of Alzheimer's disease, and this suggests that alpha-synuclein could play a mechanistic role in the pathogenesis of these disorders. To determine whether alpha-synuclein is a building block of inclusions in other neurodegenerative movement disorders, we examined brains from patients with multiple system atrophy (MSA) and detected alpha-synuclein, but not beta- or gamma-synuclein, in glial cytoplasmic inclusions (GCIs) throughout the MSA brain. In MSA white matter, alpha-synuclein-positive GCIs were restricted to oligodendrocytes, and alpha-synuclein was localized to the filaments in GCIs by immunoelectron microscopy. Finally, we demonstrated that insoluble alpha-synuclein accumulated selectively in MSA white matter with alpha-synuclein-positive GCIs. Taken together with evidence that LBs contain insoluble alpha-synuclein, our data suggest that a reduction in the solubility of alpha-synuclein may induce this protein to form filaments that aggregate into cytoplasmic inclusions, which contribute to the dysfunction or death of glial cells as well as neurons in neurodegenerative disorders with different phenotypes.

Topics: Actin Cytoskeleton; Adult; Aged; Aged, 80 and over; alpha-Synuclein; Antibodies; Female; gamma-Synuclein; Humans; Inclusion Bodies; Male; Middle Aged; Multiple System Atrophy; Myelin Sheath; Nerve Tissue Proteins; Neuroglia; Oligodendroglia; Solubility; Synucleins

Recently, we have shown that the precursor of the non-Abeta component of Alzheimer's disease amyloid (NACP), also known as alpha-synuclein, is a major component of Lewy bodies (LBs) as well as neuronal and glial cytoplasmic inclusions in multiple system atrophy (MSA). To elucidate whether the accumulation of NACP is specific to LB disease and MSA, we further studied 83 autopsied cases with various neurological disorders, using anti-NACP antibodies. In LB disease, NACP immunoreactivity was present in all of the LBs and Lewy neurites in both the central and peripheral nervous systems, the pale bodies in the substantia nigra, and dystrophic neurites in the hippocampal CA2/3 region. Immunoelectron microscopy revealed that the reaction product was localized within filamentous structures and associated granular structures. In MSA, NACP immunoreactivity was found in the intracytoplasmic inclusions of both neuronal and oligodendroglial cells, neuronal intranuclear inclusions, and swollen neuronal processes. No NACP immunoreactivity was found in a variety of other neuronal or glial inclusions in other disorders, including Alzheimer's disease, Pick's disease, progressive supranuclear palsy, corticobasal degeneration, motor neuron disease and triplet-repeat diseases. These findings strongly suggest that the accumulation of NACP is a cytopathological feature common to LB disease and MSA.

Topics: alpha-Synuclein; Cellular Senescence; Humans; Immunohistochemistry; Lewy Bodies; Microscopy, Immunoelectron; Multiple System Atrophy; Nerve Degeneration; Nerve Tissue Proteins; Nervous System Diseases; Parkinson Disease; Synucleins