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Movement Disorders Clinical Practice Apr 2021Neuroimaging has been used to support a diagnosis of possible multiple system atrophy (MSA). Only blood pressure changes upon standing are included in the second... (Review)
Review
BACKGROUND
Neuroimaging has been used to support a diagnosis of possible multiple system atrophy (MSA). Only blood pressure changes upon standing are included in the second consensus criteria but other autonomic function tests (AFT) are also useful to diagnose widespread and progressive autonomic failure typical of MSA. Additional diagnostic tools are of interest to improve accuracy of MSA diagnosis.
OBJECTIVES
To assess the utility of diagnostic tools beyond brain imaging and AFT in enhancing a laboratory-supported diagnosis of MSA to support the upcoming revision of the consensus criteria.
METHODS
The International Parkinson and Movement Disorders Society MSA Study Group (MoDiMSA) performed a systematic review of original papers on biomarkers, sleep studies, genetic, neuroendocrine, neurophysiological, neuropsychological and other tests including olfactory testing and acute levodopa challenge test published before August 2019.
RESULTS
Evaluation of history of levodopa responsiveness and olfaction is useful in patients in whom MSA-parkinsonian subtype is suspected. Neuropsychological testing is useful to exclude dementia at time of diagnosis. Applicability of sphincter EMG is limited. When MSA-cerebellar subtype is suspected, a screening for the common causes of adult-onset progressive ataxia is useful, including spinocerebellar ataxias in selected patients. Diagnosing stridor and REM sleep behavior disorder is useful in both MSA subtypes. However, none of these tools are validated in large longitudinal cohorts of postmortem confirmed MSA cases.
CONCLUSIONS
Despite limited evidence, additional laboratory work-up of patients with possible MSA beyond imaging and AFT should be considered to optimize the clinical diagnostic accuracy.
PubMed: 33816659
DOI: 10.1002/mdc3.13158 -
Frontiers in Neuroscience 2021Iron has been increasingly implicated in the pathology of neurodegenerative diseases. In the past decade, development of the new magnetic resonance imaging technique,...
Iron has been increasingly implicated in the pathology of neurodegenerative diseases. In the past decade, development of the new magnetic resonance imaging technique, quantitative susceptibility mapping (QSM), has enabled for the more comprehensive investigation of iron distribution in the brain. The aim of this systematic review was to provide a synthesis of the findings from existing QSM studies in neurodegenerative diseases. We identified 80 records by searching MEDLINE, Embase, Scopus, and PsycInfo databases. The disorders investigated in these studies included Alzheimer's disease, Parkinson's disease, amyotrophic lateral sclerosis, Wilson's disease, Huntington's disease, Friedreich's ataxia, spinocerebellar ataxia, Fabry disease, myotonic dystrophy, pantothenate-kinase-associated neurodegeneration, and mitochondrial membrane protein-associated neurodegeneration. As a general pattern, QSM revealed increased magnetic susceptibility (suggestive of increased iron content) in the brain regions associated with the pathology of each disorder, such as the amygdala and caudate nucleus in Alzheimer's disease, the substantia nigra in Parkinson's disease, motor cortex in amyotrophic lateral sclerosis, basal ganglia in Huntington's disease, and cerebellar dentate nucleus in Friedreich's ataxia. Furthermore, the increased magnetic susceptibility correlated with disease duration and severity of clinical features in some disorders. Although the number of studies is still limited in most of the neurodegenerative diseases, the existing evidence suggests that QSM can be a promising tool in the investigation of neurodegeneration.
PubMed: 33679303
DOI: 10.3389/fnins.2021.618435 -
Cerebellum & Ataxias Feb 2021Spinocerebellar ataxia is a hereditary neurodegenerative disease characterized by changes in balance, locomotion and motor coordination. Stem cell therapies are... (Review)
Review
BACKGROUND
Spinocerebellar ataxia is a hereditary neurodegenerative disease characterized by changes in balance, locomotion and motor coordination. Stem cell therapies are currently being investigated as an alternative to delay the evolution of the disease, and some experimental studies have investigated the effect of stem cell treatment on spinocerebellar ataxia.
OBJECTIVES
The aim of this review was to investigate whether the application of stem cells produced an effect on functional recovery in individuals with spinocerebellar ataxia.
METHODS
The studies included in this review investigated the efficacy and safety of a protocol for the application of mesenchymal stem cells extracted from umbilical cord and adipose tissue. Two studies used intrathecal route for application and one study used intravenous route.
RESULTS
Studies have shown clinical improvement in the scores of the ICARS (International Cooperative Ataxia Rating Scale), ADL (Activities of Daily Living Scale), BBS (Berg Balance Scale) and SARA (Scale for the Assessment and Rating of Ataxia), but lacked statistical significance.
CONCLUSIONS
There was low evidence for recommending stem cell therapy in individuals with spinocerebellar ataxia, and no statistical difference was observed for improving functional recovery of patients. Further studies are needed with different designs, largest sample sizes and placebo control, to fully understand anticipated outcomes of cellular therapy for spinocerebellar ataxia.
PubMed: 33632326
DOI: 10.1186/s40673-021-00130-8 -
Brain Sciences Apr 2020The accumulation of abnormal protein aggregates represents a universal hallmark of neurodegenerative diseases (NDDs). Post-translational modifications (PTMs) regulate... (Review)
Review
The accumulation of abnormal protein aggregates represents a universal hallmark of neurodegenerative diseases (NDDs). Post-translational modifications (PTMs) regulate protein structure and function. Dysregulated PTMs may influence the propensity for protein aggregation in NDD-proteinopathies. To investigate this, we systematically reviewed the literature to evaluate effects of PTMs on aggregation propensity for major proteins linked to the pathogenesis and/or progression of NDDs. A search of PubMed, MEDLINE, EMBASE, and Web of Science Core Collection was conducted to retrieve studies that investigated an association between PTMs and protein aggregation in seven NDDs: Alzheimer's disease (AD), Parkinson's disease (PD), Huntington's disease (HD), amyotrophic lateral sclerosis (ALS), spinocerebellar ataxias, transmissible spongiform encephalopathy, and multiple sclerosis. Together, 1222 studies were identified, of which 69 met eligibility criteria. We identified that the following PTMs, in isolation or combination, potentially act as modulators of proteinopathy in NDDs: isoaspartate formation in Aβ, phosphorylation of Aβ or tau in AD; acetylation, 4-hydroxy-2-neonal modification, -GlcNAcylation or phosphorylation of α-synuclein in PD; acetylation or phosphorylation of TAR DNA-binding protein-43 in ALS, and SUMOylation of superoxide dismutase-1 in ALS; and phosphorylation of huntingtin in HD. The potential pharmacological manipulation of these aggregation-modulating PTMs represents an as-yet untapped source of therapy to treat NDDs.
PubMed: 32290481
DOI: 10.3390/brainsci10040232 -
Movement Disorders Clinical Practice Feb 2020
PubMed: 32071950
DOI: 10.1002/mdc3.12877 -
Movement Disorders Clinical Practice Feb 2020
PubMed: 32071949
DOI: 10.1002/mdc3.12878 -
Frontiers in Neuroscience 2019Hereditary spastic paraplegia (HSP) and hereditary ataxia (HA) are two groups of disorders characterized, respectively, by progressive dysfunction or degeneration of the...
Hereditary spastic paraplegia (HSP) and hereditary ataxia (HA) are two groups of disorders characterized, respectively, by progressive dysfunction or degeneration of the pyramidal tracts (HSP) and of the Purkinje cells and spinocerebellar tracts (HA). Although HSP and HA are generally shown to have distinct clinical-genetic profiles, in several cases the clinical presentation, the causative genes, and the cellular pathways and mechanisms involved overlap between the two forms. Genetic analyses in humans in combination with and studies using model systems have greatly expanded our knowledge of spinocerebellar degenerative disorders. In this review, we focus on the zebrafish (), a vertebrate model widely used in biomedical research since its overall nervous system organization is similar to that of humans. A critical analysis of the literature suggests that zebrafish could serve as a powerful experimental tool for molecular and genetic dissection of both HA and HSP. The zebrafish, found to be very useful for demonstrating the causal relationship between defect and mutation, also offers a useful platform to exploit for the development of therapies.
PubMed: 31920481
DOI: 10.3389/fnins.2019.01311 -
Movement Disorders Clinical Practice Sep 2019The frequency and presentation of each of the most common forms of spinocerebellar ataxias (SCAs) varies widely. In the case of the Americas, this diversity is... (Review)
Review
BACKGROUND
The frequency and presentation of each of the most common forms of spinocerebellar ataxias (SCAs) varies widely. In the case of the Americas, this diversity is particularly dynamic given additional social, demographic, and cultural characteristics.
OBJECTIVE
To describe the regional prevalence and clinical phenotypes of SCAs throughout the continent.
METHODS
A literature search was performed in both MEDLINE and LILACS databases. The research was broadened to include the screening of reference lists of systematic review articles for additional studies. Investigations dating from the earliest available through 2019. Only studies in English, Portuguese, and Spanish were included. We analyzed publications with genetically confirmed cases only, ranging from robust samples with epidemiological data to case reports and case series from each country or regions.
RESULTS
Overall, SCA3 is the most common form in the continent. Region-specific prevalence and ranking of the common forms vary. On the other hand, region-specific phenotypic variations were not consistently found based on the available literature analyzed, with the exception of the absence of epilepsy in SCA10 consistently described in a particular cluster of cases in South Brazil.
CONCLUSION
Systematic, multinational studies analyzing in detail the true frequencies of SCAs across the Americas as well as distinct clinical signs and clues of each form would be ideal to look for these potential variations.
PubMed: 31538086
DOI: 10.1002/mdc3.12822 -
Seizure Jul 2019TPP1 mutations have been identified in patients with variable phenotypes such as late infantile neuronal ceroid lipofuscinosis (LINCL), juvenile neuronal ceroid...
PURPOSE
TPP1 mutations have been identified in patients with variable phenotypes such as late infantile neuronal ceroid lipofuscinosis (LINCL), juvenile neuronal ceroid lipofuscinosis (JNCL), and spinocerebellar ataxia 7. However, the mechanism underlying phenotype variation is unknown. We screened TPP1 mutations in patients with epilepsies and analyzed the genotype-phenotype correlation to explain the phenotypic variations.
METHODS
We performed targeted next-generation sequencing in a cohort of 330 patients with epilepsies. All previously reported TPP1 mutations were systematically retrieved from the PubMed and NCL Mutation Database.
RESULTS
The homozygous missense TPP1 mutation c.646 G > A/ p.Val216Met was identified in a family with two affected siblings. The proband presented with seizures from three years of age, while no ataxia, cognitive regression, or visual abnormalities were observed. Further analysis of all reported TPP1 mutations revealed that the LINCL group had a significantly higher frequency of truncating and invariant splice-site mutations than the JNCL group. In contrast, the JNCL group had a higher frequency of variant splice-site mutations than LINCL. There was a significant correlation between phenotype severity and the frequency of destructive mutation.
CONCLUSION
This study suggested that the phenotype of mainly epilepsy can be included in the phenotypic spectrum of TPP1 mutations, which are candidate targets for genetic screening in patients with epilepsy. With the development of therapy techniques, early genetic diagnosis may enable the improvement of etiology-targeted treatments. The relationship between phenotype severity and the genotype of TPP1 mutations may help explain the phenotypic variations.
Topics: Aminopeptidases; Brain; Child; Child, Preschool; Cohort Studies; Dipeptidyl-Peptidases and Tripeptidyl-Peptidases; Epilepsy; Female; Genetic Association Studies; Humans; Male; Mutation, Missense; Neuronal Ceroid-Lipofuscinoses; Phenotype; Serine Proteases; Severity of Illness Index; Siblings; Tripeptidyl-Peptidase 1
PubMed: 31059981
DOI: 10.1016/j.seizure.2018.08.027 -
Neurology Mar 2018To systematically review evidence regarding ataxia treatment.
Comprehensive systematic review summary: Treatment of cerebellar motor dysfunction and ataxia: Report of the Guideline Development, Dissemination, and Implementation Subcommittee of the American Academy of Neurology.
OBJECTIVE
To systematically review evidence regarding ataxia treatment.
METHODS
A comprehensive systematic review was performed according to American Academy of Neurology methodology.
CONCLUSIONS
For patients with episodic ataxia type 2, 4-aminopyridine 15 mg/d probably reduces ataxia attack frequency over 3 months (1 Class I study). For patients with ataxia of mixed etiology, riluzole probably improves ataxia signs at 8 weeks (1 Class I study). For patients with Friedreich ataxia or spinocerebellar ataxia (SCA), riluzole probably improves ataxia signs at 12 months (1 Class I study). For patients with SCA type 3, valproic acid 1,200 mg/d possibly improves ataxia at 12 weeks. For patients with spinocerebellar degeneration, thyrotropin-releasing hormone possibly improves some ataxia signs over 10 to 14 days (1 Class II study). For patients with SCA type 3 who are ambulatory, lithium probably does not improve signs of ataxia over 48 weeks (1 Class I study). For patients with Friedreich ataxia, deferiprone possibly worsens ataxia signs over 6 months (1 Class II study). Data are insufficient to support or refute the use of numerous agents. For nonpharmacologic options, in patients with degenerative ataxias, 4-week inpatient rehabilitation probably improves ataxia and function (1 Class I study); transcranial magnetic stimulation possibly improves cerebellar motor signs at 21 days (1 Class II study). For patients with multiple sclerosis-associated ataxia, the addition of pressure splints possibly has no additional benefit compared with neuromuscular rehabilitation alone (1 Class II study). Data are insufficient to support or refute use of stochastic whole-body vibration therapy (1 Class III study).
Topics: Ataxia; Cerebellar Diseases; Humans
PubMed: 29440566
DOI: 10.1212/WNL.0000000000005055