Identification of metabolic pathways and key genes associated with atypical parkinsonism using a systems biology approach.

Atypical parkinsonism (AP) is a group of complex neurodegenerative disorders with marked clinical and pathophysiological heterogeneity. The use of systems biology tools may contribute to the characterization of hub-bottleneck genes, and the identification of its biological pathways to broaden the understanding of the bases of these disorders. A systematic search was performed on the DisGeNET database, which integrates data from expert curated repositories, GWAS catalogues, animal models and the scientific literature. The tools STRING 11.0 and Cytoscape 3.8.2 were used for analysis of protein-protein interaction (PPI) network. The PPI network topography analyses were performed using the CytoHubba 0.1 plugin for Cytoscape. The hub and bottleneck genes were inserted into 4 different sets on the InteractiveVenn. Additional functional enrichment analyses were performed to identify Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways and gene ontology for a described set of genes. The systematic search in the DisGeNET database identified 485 genes involved with Atypical Parkinsonism. Superimposing these genes, we detected a total of 31 hub-bottleneck genes. Moreover, our functional enrichment analyses demonstrated the involvement of these hub-bottleneck genes in 3 major KEGG pathways. We identified 31 highly interconnected hub-bottleneck genes through a systems biology approach, which may play a key role in the pathogenesis of atypical parkinsonism. The functional enrichment analyses showed that these genes are involved in several biological processes and pathways, such as the glial cell development, glial cell activation and cognition, pathways were related to Alzheimer disease and Parkinson disease. As a hypothesis, we highlight as possible key genes for AP the MAPT (microtubule associated protein tau), APOE (apolipoprotein E), SNCA (synuclein alpha) and APP (amyloid beta precursor protein) genes.

Clinical correlates of fear of falling in progressive supranuclear palsy and multiple system atrophy.

BACKGROUND AND PURPOSE: Clinical correlates of fear of falling (FoF) are scarcely studied in patients with progressive supranuclear palsy (PSP) and multiple system atrophy (MSA). This study was undertaken to evaluate the clinical correlates of FoF in PSP and MSA. METHODS: This cross-sectional study features motor, cognitive, and psychiatric assessment and longitudinal evaluation of falls and FoF at 6-month follow-up. RESULTS: Twenty-one patients with PSP-parkinsonism, 22 patients with MSA (13 parkinsonian type and nine cerebellar type), and 22 healthy controls were evaluated; 76.2% of patients with PSP and 86.4% of patients with MSA had FoF regardless of falls. Berg Balance Scale (p < 0.001), Tinetti Mobility Test (p < 0.01), Beck Anxiety Inventory (p = 0.001), and Beck Depression Inventory-II (p = 0.01) correlated with FoF in patients with PSP and MSA, whereas Timed Up and Go test (p = 0.01) and Starkstein Apathy Scale correlated only in MSA (p = 0.04). CONCLUSIONS: Mobility, balance, and gait performance as well as anxiety and depression in PSP and MSA, and apathy in MSA, were determinants of FoF. These findings underline the importance of a multidisciplinary approach to FoF in neurodegenerative atypical parkinsonism.

Further evidence for a distinctive atypical degenerative parkinsonism in the Caribbean: A new cluster in the French West Indian Island of Martinique.

BACKGROUND: A high prevalence of an atypical levodopa-resistant parkinsonism has been reported in the Caribbean island of Guadeloupe. These seminal observations have not been replicated or extended to neighbouring populations who share genetic and environmental characteristics. METHODS: To further characterise this atypical parkinsonism we prospectively investigated 305 consecutive patients with neurodegenerative parkinsonism in a community-based population from Guadeloupe and Martinique, a neighbouring French Caribbean island where the population has similar environmental and genetic backgrounds. The aims of this study were to confirm the frequency of atypical parkinsonism within this cohort and to precisely define its clinical phenotype. RESULTS: A high frequency (66%) of atypical parkinsonism was identified in both Guadeloupe and Martinique. The clinical phenotype consisted of a levodopa-resistant parkinsonism with postural instability (72%), early dementia (58%), dysautonomia (58%), rapid-eye-movement sleep behavioural disorder (53%), hallucinations (43%), and supranuclear gaze palsy (29%). A low educational level was identified as a major risk factor for developing atypical parkinsonism (p < .001). CONCLUSION: Our findings support the existence of a distinctive atypical parkinsonism - Caribbean Parkinsonism - within the French Caribbean Islands. This could either correspond to a single entity or reflect a propensity for developing more widespread and rapidly progressive lesions in Caribbean patients with parkinsonism. In both cases, genetic susceptibility and/or environmental exposure may be involved.

DCTN1-related neurodegeneration: Perry syndrome and beyond.

Perry syndrome (PS) is a rare hereditary neurodegenerative disease characterized by autosomal dominant parkinsonism, psychiatric symptoms, weight loss, central hypoventilation, and distinct TDP-43 pathology. The mutated causative gene for PS is DCTN1, which encodes the dynactin subunit p150Glued. Dynactin is a motor protein involved in axonal transport; the p150Glued subunit has a critical role in the overall function. Since the discovery of DCTN1 in PS, it has been increasingly recognized that DCTN1 mutations can exhibit more diverse phenotypes than previously thought. Progressive supranuclear palsy- and/or frontotemporal dementia-like phenotypes have been associated with the PS phenotypes. In addition, DCTN1 mutations were identified in a family with motor-neuron disease before the discovery in PS. In this review, we analyze the clinical and genetic aspects of DCTN1-related neurodegeneration and discuss its pathogenesis. We also describe three families with PS, Canadian, Polish, and Brazilian. DCTN1 mutation was newly identified in two of them, the Canadian and Polish families. The Canadian family was first described in late 1970's but was never genetically tested. We recently had the opportunity to evaluate this family and to test the gene status of an affected family member. The Polish family is newly identified and is the first PS family in Poland. Although still rare, DCTN1-related neurodegeneration needs to be considered in a differential diagnosis of parkinsonian disorders, frontotemporal dementia, and motor-neuron diseases, especially if there is family history.

Corticobasal syndrome: a diagnostic conundrum / O enigmático diagnóstico da síndrome Corticobasal

ABSTRACT Corticobasal syndrome (CBS) is an atypical parkinsonian syndrome of great interest to movement disorder specialists and behavioral neurologists. Although originally considered a primary motor disorder, it is now also recognized as a cognitive disorder, usually presenting cognitive deficits before the onset of motor symptoms. The term CBS denotes the clinical phenotype and is associated with a heterogeneous spectrum of pathologies. Given that disease-modifying agents are targeting the pathologic process, new diagnostic methods and biomarkers are being developed to predict the underlying pathology. The heterogeneity of this syndrome in terms of clinical, radiological, neuropsychological and pathological aspects poses the main challenge for evaluation.

RESUMO A síndrome corticobasal é classificada dentro do grupo das síndromes parkinsonianas atípicas, e atualmente desperta interesse em neurologistas especialistas em distúrbios do movimento e neurologia cognitiva e comportamental. Inicialmente considerada como uma síndrome tipicamente motora, hoje se reconhece a importância dos achados cognitivos na apresentação, podendo ocorrer mesmo na ausência de alterações motoras. Tal designação refere-se à síndrome clínica e é associada a várias patologias subjacentes. Tendo em vista que drogas modificadoras da doença estão focando na patologia de base, novos métodos diagnósticos de imagem e outros biomarcadores estão sendo desenvolvidos para predizer o processo patológico específico antemortem. A heterogeneidade clínica e patológica desta entidade, portanto, é o maior desafio a ser desvendado.

Corticobasal syndrome: A diagnostic conundrum.

Corticobasal syndrome (CBS) is an atypical parkinsonian syndrome of great interest to movement disorder specialists and behavioral neurologists. Although originally considered a primary motor disorder, it is now also recognized as a cognitive disorder, usually presenting cognitive deficits before the onset of motor symptoms. The term CBS denotes the clinical phenotype and is associated with a heterogeneous spectrum of pathologies. Given that disease-modifying agents are targeting the pathologic process, new diagnostic methods and biomarkers are being developed to predict the underlying pathology. The heterogeneity of this syndrome in terms of clinical, radiological, neuropsychological and pathological aspects poses the main challenge for evaluation.

A síndrome corticobasal é classificada dentro do grupo das síndromes parkinsonianas atípicas, e atualmente desperta interesse em neurologistas especialistas em distúrbios do movimento e neurologia cognitiva e comportamental. Inicialmente considerada como uma síndrome tipicamente motora, hoje se reconhece a importância dos achados cognitivos na apresentação, podendo ocorrer mesmo na ausência de alterações motoras. Tal designação refere-se à síndrome clínica e é associada a várias patologias subjacentes. Tendo em vista que drogas modificadoras da doença estão focando na patologia de base, novos métodos diagnósticos de imagem e outros biomarcadores estão sendo desenvolvidos para predizer o processo patológico específico antemortem. A heterogeneidade clínica e patológica desta entidade, portanto, é o maior desafio a ser desvendado.

Cognitive impairment in multiple system atrophy - changing concepts / Comprometimento cognitivo na atrofia de múltiplos sistemas - mudando os conceitos

Multiple system atrophy (MSA) is characterized by a variable combination of cerebellar ataxia, parkinsonism and pyramidal signs associated with autonomic failure. Classically, cognitive impairment was not considered a clinical feature of MSA and dementia was pointed out as an exclusion diagnostic criteria. Based on comprehensive neuropsychological assessment, cognitive impairment was found to be a frequent feature in MSA, and clinically-defined dementia is now reported in 14-16% of cases. This article reviews the current data on cognitive impairment in MSA along with its neuropsychological profile and pathophysiology.

A Atrofia de Múltiplos Sistemas (AMS) é caracterizada por uma combinação variável de ataxia cerebelar, parkinsonismo e sinais piramidais, associados à disfunção autonômica. Classicamente, o comprometimento cognitivo não é considerado como manifestação clínica da AMS e a demência é apontada como um critério de exclusão para o diagnóstico. Baseado na avaliação neuropsicológica ampla, o comprometimento neuropsicológico revelou-se frequente na AMS e a presença de demência é atualmente descrita em 14-16% dos casos. Este artigo revisa os dados atuais sobre o comprometimento cognitivo na AMS, seu perfil neuropsicológico e fisiopatologia.

Cognitive impairment in multiple system atrophy: Changing concepts.

Multiple system atrophy (MSA) is characterized by a variable combination of cerebellar ataxia, parkinsonism and pyramidal signs associated with autonomic failure. Classically, cognitive impairment was not considered a clinical feature of MSA and dementia was pointed out as an exclusion diagnostic criteria. Based on comprehensive neuropsychological assessment, cognitive impairment was found to be a frequent feature in MSA, and clinically-defined dementia is now reported in 14-16% of cases. This article reviews the current data on cognitive impairment in MSA along with its neuropsychological profile and pathophysiology.

A Atrofia de Múltiplos Sistemas (AMS) é caracterizada por uma combinação variável de ataxia cerebelar, parkinsonismo e sinais piramidais, associados à disfunção autonômica. Classicamente, o comprometimento cognitivo não é considerado como manifestação clínica da AMS e a demência é apontada como um critério de exclusão para o diagnóstico. Baseado na avaliação neuropsicológica ampla, o comprometimento neuropsicológico revelou-se frequente na AMS e a presença de demência é atualmente descrita em 14-16% dos casos. Este artigo revisa os dados atuais sobre o comprometimento cognitivo na AMS, seu perfil neuropsicológico e fisiopatologia.

Progressive supranuclear palsy: new concepts / Paralisia supranuclear progressiva: conceitos atuais

Progressive supranuclear palsy (PSP) is a distinctive form of neurodegenerative disease which affects the brainstem and basal ganglia. Patients present supranuclear ophthalmoplegia, postural instability and mild dementia. PSP is defined neuropathologically by the accumulation of neurofibrillary tangles in the subthalamic nucleus, pallidum, red nucleus, substantia nigra, striatum, pontine tegmentum, oculomotor nucleus, medulla and dentate nucleus. Over the last decade many lines of investigations have helped refine PSP in many aspects and it is the purpose of this review to help neurologists identify PSP, to better understand its pathophysiology and to provide a more focused, symptom-based treatment approach.

A paralisia supranuclear progressiva (PSP) é uma doença neurodegenerativa, que afeta principalmente o tronco cerebral e os núcleos da base. O quadro clínico se caracteriza por oftalmoparesia supranuclear, instabilidade postural e demência . Do ponto de vista anátomo-patológico, a PSP se caracteriza por acúmulo de emaranhados neurofibrilares no núcleo subtalâmico, globo pálido, núcleo rubro, substância negra, estriado, tegumento da ponte, núcleos oculomotores, bulbo e núcleo denteado. Nas últimas décadas, muitas linhas de pesquisa têm colaborado para redefinir a PSP em muitos aspectos. Os objetivos dessa revisão são auxiliar o neurologista geral na identificação da doença, compreensão da sua fisiopatologia, além de apresentar alternativas para seu tratamento sintomático.

Clinical features of dystonia in atypical parkinsonism / Características clínicas da distonia no parkinsonismo atípico

BACKGROUND: The association between Dystonia and Parkinson's disease (PD) has been well described especially for foot and hand dystonia. There is however few data on dystonic postures in patients with atypical parkinsonism. OBJECTIVE: To evaluate the frequency and pattern of dystonia in a group of patients with atypical parkinsonism (multiple system atrophy - MSA, progressive supranuclear palsy - PSP, and corticobasal degeneration - CBD) and to investigate whether dystonia could be the first presenting symptom at disease onset in those patients. METHOD: A total of 38 medical charts were reviewed (n=23/MSA group; n=7/CBD group; n=8/PSP group) and data values were described as means/standard deviations. The variables evaluated were sex, age at onset, disease duration, first symptom, clinical features of dystonia and other neurological signs, response to levodopatherapy, Hoehn&Yahr scale >3 after three years of disease, and magnetic resonance imaging findings. RESULTS: The overall frequency of dystonia in our sample was 50 percent with 30.4 percent (n=7) in the MSA group, 62.5 percent (n=5) in the PSP group, and 100 percent (n=8) in the CBD group. In none of these patients, dystonia was the first complaint. Several types of dystonia were found: camptocormia, retrocollis, anterocollis, blepharoespasm, oromandibular, and foot/hand dystonia. CONCLUSION: In our series, dystonia was a common feature in atypical parkinsonism (overall frequency of 50 percent) and it was part of the natural history although not the first symptom at disease onset. Neuroimaging abnormalities are not necessarily related to focal dystonia, and levodopa therapy did not influence the pattern of dystonia in our group of patients.

INTRODUÇÃO: A associação de distonia e doença de Parkinson (DP) já foi bem estabelecida, principalmente para distonia focal em pé ou mão. Entretanto, há poucos dados quanto a distonia em pacientes com parkinsonismo atípico. OBJETIVO: Avaliar a freqüência e o padrão da distonia em um grupo de pacientes com parkisnonismo atípico (atrofia de múltiplos sistemas - AMS; paralisia supranuclear progressiva - PSP; degeneração corticobasal - DCB) e investigar se a distonia pode ser a manifestação inicial neste grupo. MÉTODO: Um total de 38 prontuários médicos foi revisado (n=23/grupo AMS; n=8/grupo PSP; n=7/grupo PSP) e os dados foram apresentados em médias/desvios padrões. As variaveis avaliadas foram: sexo, idade de início, duração da doença, primeiro sintoma, características clínicas da distonia e outros sinais neurológicos, resposta ao tratamento com levodopa, escala de Hoehn & Yahr >3 em 3 anos de doença, e achados de ressonância magnética. RESULTADOS: A frequência total de distonia em nosso grupo foi 50 por cento, sendo 30,4 por cento (n=7) no grupo AMS, 62.5 por cento (n=5) no grupo PSP e 100 por cento (n=8) no grupo DCB. Em nenhum dos pacientes, distonia foi o primeiro sintoma. Várias apresentações de distonia foram observadas: camptocormia, anterocólis, retrocólis, distonia oromandibular, em pé e mão. CONCLUSÃO: Em nossa série, distonia foi uma característica comum em pacientes com parkinsonismo atípico (freqüência de 50 por cento) e fez parte da história natural em todos os grupos, embora não tenha sido o sintoma inicial em nenhum deles. Anormalidades no exame de neuroimagem não necessariamente estão relacionadas a distonia focal, e o tratamento com levodopa não influenciou o padrão da distonia em nosso grupo de pacientes.

Síntomas psiquiátricos de la parálisis supranuclear progresiva / Psychiatric Symptoms of Progressive Supranuclear Palsy

Introducción: Se presenta el caso de un paciente de 73 años, con diagnóstico de parálisis supranuclear progresiva (PSP), quien ingresa a la unidad de salud mental por presencia de síntomas psicóticos con poca respuesta al uso de antipsicóticos y medicación antiparkinsoniana. Objetivo: Revisar las principales alteraciones clínicas de los pacientes con este diagnóstico, las teorías etiopatológicas y las conductas que se deben seguir frente a esta entidad. Método: Reporte de caso. Desarrollo y conclusión: La PSP, aunque poco común, es de interés psiquiátrico, ya que cursa a menudo con síntomas psicóticos y es frecuentemente diagnosticada como una enfermedad psiquiátrica.

Introduction: This is a case report of a 73 year old man, with a diagnosis of progressive supranuclear palsy (PSP) who is admitted to a mental health unit with psychotic symptoms with little response to antipsychotic and antiparkinsonian medication. Objective: This case report emphasizes the clinical symptoms of patients with this diagnosis, the etiopathological theories and the most accurate treatment for this disease. Design: Case report. Development and conclusion: PSP, though rare, is of interest to psychiatry because of the common occurrence of psychiatric symptoms and the frequent misdiagnosis with psychiatric illness.