scholarly journals Emerging Mechanisms Underpinning Neurophysiological Impairments in C9ORF72 Repeat Expansion-Mediated Amyotrophic Lateral Sclerosis/Frontotemporal Dementia

2021 ◽  
Vol 15 ◽  
Author(s):  
Iris-Stefania Pasniceanu ◽  
Manpreet Singh Atwal ◽  
Cleide Dos Santos Souza ◽  
Laura Ferraiuolo ◽  
Matthew R. Livesey
Keyword(s):  
Amyotrophic Lateral Sclerosis ◽  
Frontotemporal Dementia ◽  
Motor Neurons ◽  
Molecular Mechanisms ◽  
Repeat Expansion ◽  
Neuronal Function ◽  
Repeat Expansion Mutation ◽  
Expansion Mutation ◽  
The Impact ◽  
Lateral Sclerosis

Amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) are characterized by degeneration of upper and lower motor neurons and neurons of the prefrontal cortex. The emergence of the C9ORF72 hexanucleotide repeat expansion mutation as the leading genetic cause of ALS and FTD has led to a progressive understanding of the multiple cellular pathways leading to neuronal degeneration. Disturbances in neuronal function represent a major subset of these mechanisms and because such functional perturbations precede degeneration, it is likely that impaired neuronal function in ALS/FTD plays an active role in pathogenesis. This is supported by the fact that ALS/FTD patients consistently present with neurophysiological impairments prior to any apparent degeneration. In this review we summarize how the discovery of the C9ORF72 repeat expansion mutation has contributed to the current understanding of neuronal dysfunction in ALS/FTD. Here, we discuss the impact of the repeat expansion on neuronal function in relation to intrinsic excitability, synaptic, network and ion channel properties, highlighting evidence of conserved and divergent pathophysiological impacts between cortical and motor neurons and the influence of non-neuronal cells. We further highlight the emerging association between these dysfunctional properties with molecular mechanisms of the C9ORF72 mutation that appear to include roles for both, haploinsufficiency of the C9ORF72 protein and aberrantly generated dipeptide repeat protein species. Finally, we suggest that relating key pathological observations in C9ORF72 repeat expansion ALS/FTD patients to the mechanistic impact of the C9ORF72 repeat expansion on neuronal function will lead to an improved understanding of how neurophysiological dysfunction impacts upon pathogenesis.

Analysis of known amyotrophic lateral sclerosis and frontotemporal dementia genes reveals a substantial genetic burden in patients manifesting both diseases not carrying the C9orf72 expansion mutation

2017 ◽  
Vol 89 (2) ◽  
pp. 162-168 ◽  
Author(s):  
Oriol Dols-Icardo ◽  
Alberto García-Redondo ◽  
Ricardo Rojas-García ◽  
Daniel Borrego-Hernández ◽  
Ignacio Illán-Gala ◽  
...  
Keyword(s):  
Amyotrophic Lateral Sclerosis ◽  
Frontotemporal Dementia ◽  
Pathogenic Mutation ◽  
Genetic Alterations ◽  
Repeat Expansion ◽  
Chromosome 9 ◽  
Systematic Screening ◽  
Expansion Mutation ◽  
Genetic Burden ◽  
Lateral Sclerosis

Amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) are part of a clinical, pathological and genetic continuum.ObjectivesThe purpose of the present study was to assess the mutation burden that is present in patients with concurrent ALS and FTD (ALS/FTD) not carrying the chromosome 9 open reading frame 72 (C9orf72) hexanucleotide repeat expansion, the most important genetic cause in both diseases.MethodsFrom an initial group of 973 patients with ALS, we retrospectively selected those patients fulfilling diagnostic criteria of concomitant ALS and FTD lacking the repeat expansion mutation in C9orf72. Our final study group consisted of 54 patients clinically diagnosed with ALS/FTD (16 with available postmortem neuropathological diagnosis). Data from whole exome sequencing were used to screen for mutations in known ALS and/or FTD genes.ResultsWe identified 11 patients carrying a probable pathogenic mutation, representing an overall mutation frequency of 20.4%. TBK1 was the most important genetic cause of ALS/FTD (n=5; 9.3%). The second most common mutated gene was SQSTM1, with three mutation carriers (one of them also harboured a TBK1 mutation). We also detected probable pathogenic genetic alterations in TAF15, VCP and TARDBP and possible pathogenic mutations in FIG4 and ERBB4.ConclusionOur results indicate a high genetic burden underlying the co-occurrence of ALS and FTD and expand the phenotype associated with TAF15, FIG4 and ERBB4 to FTD. A systematic screening of ALS and FTD genes could be indicated in patients manifesting both diseases without the C9orf72 expansion mutation, regardless of family history of disease.

scholarly journals Immune Signaling Kinases in Amyotrophic Lateral Sclerosis (ALS) and Frontotemporal Dementia (FTD)

2021 ◽  
Vol 22 (24) ◽  
pp. 13280
Author(s):  
Raquel García-García ◽  
Laura Martín-Herrero ◽  
Laura Blanca-Pariente ◽  
Jesús Pérez-Cabello ◽  
Cintia Roodveldt
Keyword(s):  
Amyotrophic Lateral Sclerosis ◽  
Frontotemporal Dementia ◽  
Motor Neurons ◽  
Molecular Mechanisms ◽  
Neurodegenerative Disorder ◽  
Therapeutic Potential ◽  
Neuronal Loss ◽  
Immune Signaling ◽  
Health And Disease ◽  
Lateral Sclerosis

Amyotrophic lateral sclerosis (ALS) is the most common neurodegenerative disorder of motor neurons in adults, with a median survival of 3–5 years after appearance of symptoms, and with no curative treatment currently available. Frontotemporal dementia (FTD) is also an adult-onset neurodegenerative disease, displaying not only clinical overlap with ALS, but also significant similarities at genetic and pathologic levels. Apart from the progressive loss of neurons and the accumulation of protein inclusions in certain cells and tissues, both disorders are characterized by chronic inflammation mediated by activated microglia and astrocytes, with an early and critical impact of neurodegeneration along the disease course. Despite the progress made in the last two decades in our knowledge around these disorders, the underlying molecular mechanisms of such non-cell autonomous neuronal loss still need to be clarified. In particular, immune signaling kinases are currently thought to have a key role in determining the neuroprotective or neurodegenerative nature of the central and peripheral immune states in health and disease. This review provides a comprehensive and updated view of the proposed mechanisms, therapeutic potential, and ongoing clinical trials of immune-related kinases that have been linked to ALS and/or FTD, by covering the more established TBK1, RIPK1/3, RACK I, and EPHA4 kinases, as well as other emerging players in ALS and FTD immune signaling.

scholarly journals Coexistence of neuronal intranuclear inclusion disease and amyotrophic lateral sclerosis: an autopsy case

BMC Neurology ◽  
2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Atsuhiko Sugiyama ◽  
Takahiro Takeda ◽  
Mizuho Koide ◽  
Hajime Yokota ◽  
Hiroki Mukai ◽  
...  
Keyword(s):  
Amyotrophic Lateral Sclerosis ◽  
Motor Neurons ◽  
Brain Mri ◽  
Brain Magnetic Resonance Imaging ◽  
Repeat Expansion ◽  
Cerebellar Hemisphere ◽  
Intranuclear Inclusions ◽  
Intranuclear Inclusion ◽  
Neuronal Intranuclear Inclusion ◽  
Lateral Sclerosis

Abstract Background Neuronal intranuclear inclusion disease (NIID) is a rare neurodegenerative disease. Pathologically, it is characterized by eosinophilic hyaline intranuclear inclusions in the cells of the visceral organs as well as central, peripheral, and autonomic nervous system cells. Recently, a GGC repeat expansion in the NOTCH2NLC gene has been identified as the etiopathological agent of NIID. Interestingly, this GGC repeat expansion was also reported in some patients with a clinical diagnosis of amyotrophic lateral sclerosis (ALS). However, there are no autopsy-confirmed cases of concurrent NIID and ALS. Case presentation A 60-year-old Taiwanese woman reported a four-month history of progressive weakness beginning in the right foot that spread to all four extremities. She was diagnosed with ALS because she met the revised El Escorial diagnostic criteria for definite ALS with upper and lower motor neuron involvement in the cervical, thoracic, and lumbosacral regions. She died of respiratory failure at 22 months from ALS onset, at the age of 62 years. Brain magnetic resonance imaging (MRI) revealed lesions in the medial part of the cerebellar hemisphere, right beside the vermis (paravermal lesions). The subclinical neuropathy, indicated by a nerve conduction study (NCS), prompted a potential diagnosis of NIID. Antemortem skin biopsy and autopsy confirmed the coexistence of pathology consistent with both ALS and NIID. We observed neither eccentric distribution of p62-positive intranuclear inclusions in the areas with abundant large motor neurons nor cytopathological coexistence of ALS and NIID pathology in motor neurons. This finding suggested that ALS and NIID developed independently in this patient. Conclusions We describe a case of concurrent NIID and ALS discovered during an autopsy. Abnormal brain MRI findings, including paravermal lesions, could indicate the coexistence of NIID even in patients with ALS showing characteristic clinical phenotypes.

scholarly journals The Emerging Role of DNA Damage in the Pathogenesis of the C9orf72 Repeat Expansion in Amyotrophic Lateral Sclerosis

2018 ◽  
Vol 19 (10) ◽  
pp. 3137 ◽  
Author(s):  
Anna Konopka ◽  
Julie Atkin
Keyword(s):  
Dna Damage ◽  
Amyotrophic Lateral Sclerosis ◽  
Motor Neurons ◽  
Repeat Expansion ◽  
Chromosome 9 ◽  
Gene Encoding ◽  
C9orf72 Repeat Expansion ◽  
Reading Frame ◽  
Early Onset Dementia ◽  
Lateral Sclerosis

Amyotrophic lateral sclerosis (ALS) is a fatal, rapidly progressing neurodegenerative disease affecting motor neurons, and frontotemporal dementia (FTD) is a behavioural disorder resulting in early-onset dementia. Hexanucleotide (G4C2) repeat expansions in the gene encoding chromosome 9 open reading frame 72 (C9orf72) are the major cause of familial forms of both ALS (~40%) and FTD (~20%) worldwide. The C9orf72 repeat expansion is known to form abnormal nuclei acid structures, such as hairpins, G-quadruplexes, and R-loops, which are increasingly associated with human diseases involving microsatellite repeats. These configurations form during normal cellular processes, but if they persist they also damage DNA, and hence are a serious threat to genome integrity. It is unclear how the repeat expansion in C9orf72 causes ALS, but recent evidence implicates DNA damage in neurodegeneration. This may arise from abnormal nucleic acid structures, the greatly expanded C9orf72 RNA, or by repeat-associated non-ATG (RAN) translation, which generates toxic dipeptide repeat proteins. In this review, we detail recent advances implicating DNA damage in C9orf72-ALS. Furthermore, we also discuss increasing evidence that targeting these aberrant C9orf72 confirmations may have therapeutic value for ALS, thus revealing new avenues for drug discovery for this disorder.

scholarly journals Frontotemporal dementia and amyotrophic lateral sclerosis: Revisiting one of the first case reports with neuropathological examination

2014 ◽  
Vol 8 (1) ◽  
pp. 83-86 ◽  
Author(s):  
Ricardo Nitrini
Keyword(s):  
Amyotrophic Lateral Sclerosis ◽  
Frontotemporal Dementia ◽  
Motor Neurons ◽  
Case Reports ◽  
Rare Event ◽  
Motor Impairments ◽  
Late 20Th Century ◽  
First Case ◽  
Lateral Sclerosis ◽  
Neuropathological Examination

ABSTRACT The occurrence of dementia in amyotrophic lateral sclerosis (ALS) was only widely recognized in the late 20th century. Hitherto, it was believed that dementia was a rare event due to the fortuitous association with other diseases. In 1924, Kostantin Nikolaevich Tretiakoff and Moacyr de Freitas Amorim reported a case of dementia with features of frontotemporal dementia (FTD) that preceded the motor signs of ALS. Neuropathological examination confirmed ALS and found no signs of other dementia-causing diseases. The authors hypothesized that dementia was part of ALS and recommended the search for signs of involvement of motor neurons in cases of dementia with an ill-defined clinical picture, a practice currently accepted in the investigation of cases of FTD. This was one of the first descriptions of dementia preceding the motor impairments of ALS and was published in Portuguese and French in Memórias do Hospício de Juquery.

scholarly journals Spatiotemporal Dynamics of Molecular Pathology in Amyotrophic Lateral Sclerosis

2018 ◽  
Author(s):  
Silas Maniatis ◽  
Tarmo Äijö ◽  
Sanja Vickovic ◽  
Catherine Braine ◽  
Kristy Kang ◽  
...  
Keyword(s):  
Amyotrophic Lateral Sclerosis ◽  
Motor Neuron ◽  
Motor Neurons ◽  
Molecular Mechanisms ◽  
Early Time ◽  
Spatiotemporal Dynamics ◽  
Course Of Disease ◽  
Molecular Events ◽  
Als Patients ◽  
Lateral Sclerosis

AbstractParalysis occurring in amyotrophic lateral sclerosis (ALS) results from denervation of skeletal muscle as a consequence of motor neuron degeneration. Interactions between motor neurons and glia contribute to motor neuron loss, but the spatiotemporal ordering of molecular events that drive these processes in intact spinal tissue remains poorly understood. Here, we use spatial transcriptomics to obtain gene expression measurements of mouse spinal cords over the course of disease, as well as of postmortem tissue from ALS patients, to characterize the underlying molecular mechanisms in ALS. We identify novel pathway dynamics, regional differences between microglia and astrocyte populations at early time-points, and discern perturbations in several transcriptional pathways shared between murine models of ALS and human postmortem spinal cords.One Sentence SummaryAnalysis of the ALS spinal cord using Spatial Transcriptomics reveals spatiotemporal dynamics of disease driven gene regulation.

scholarly journals Spatiotemporal dynamics of molecular pathology in amyotrophic lateral sclerosis

Science ◽  
2019 ◽  
Vol 364 (6435) ◽  
pp. 89-93 ◽  
Author(s):  
Silas Maniatis ◽  
Tarmo Äijö ◽  
Sanja Vickovic ◽  
Catherine Braine ◽  
Kristy Kang ◽  
...  
Keyword(s):  
Amyotrophic Lateral Sclerosis ◽  
Motor Neuron ◽  
Motor Neurons ◽  
Molecular Mechanisms ◽  
Early Time ◽  
Course Of Disease ◽  
Molecular Events ◽  
Motor Neuron Loss ◽  
Als Patients ◽  
Lateral Sclerosis

Paralysis occurring in amyotrophic lateral sclerosis (ALS) results from denervation of skeletal muscle as a consequence of motor neuron degeneration. Interactions between motor neurons and glia contribute to motor neuron loss, but the spatiotemporal ordering of molecular events that drive these processes in intact spinal tissue remains poorly understood. Here, we use spatial transcriptomics to obtain gene expression measurements of mouse spinal cords over the course of disease, as well as of postmortem tissue from ALS patients, to characterize the underlying molecular mechanisms in ALS. We identify pathway dynamics, distinguish regional differences between microglia and astrocyte populations at early time points, and discern perturbations in several transcriptional pathways shared between murine models of ALS and human postmortem spinal cords.

Sign in / Sign up

Export Citation Format

Share Document