300 research outputs found

    Quo vadis motor neuron disease?

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    Motor neuron disease (MND), also known as amyotrophic lateral sclerosis, is a relentlessly progressive neurodegenerative condition that is invariably fatal, usually within 3 to 5 years of diagnosis. The aetio-pathogenesis of MND remains unresolved and no effective treatments exist. The only Food and Drug Administration approved disease modifying therapy is riluzole, a glutamate antagonist, which prolongs survival by up to 3 mo. Current management is largely symptomatic/supportive. There is therefore a desperate and unmet clinical need for discovery of disease mechanisms to guide novel therapeutic strategy. In this review, we start by introducing the organizational anatomy of the motor system, before providing a clinical overview of its dysfunction specifically in MND. We then summarize insights gained from pathological, genetic and animal models and conclude by speculating on optimal strategies to drive the step change in discovery, which is so desperately needed in this arena

    Stress-Specific Spatiotemporal Responses of RNA-Binding Proteins in Human Stem-Cell-Derived Motor Neurons

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    RNA-binding proteins (RBPs) have been shown to play a key role in the pathogenesis of a variety of neurodegenerative disorders. Amyotrophic lateral sclerosis (ALS) is an exemplar neurodegenerative disease characterised by rapid progression and relatively selective motor neuron loss. Nuclear-to-cytoplasmic mislocalisation and accumulation of RBPs have been identified as a pathological hallmark of the disease, yet the spatiotemporal responses of RBPs to different extrinsic stressors in human neurons remain incompletely understood. Here, we used healthy induced pluripotent stem cell (iPSC)-derived motor neurons to model how different types of cellular stress affect the nucleocytoplasmic localisation of key ALS-linked RBPs. We found that osmotic stress robustly induced nuclear loss of TDP-43, SPFQ, FUS, hnRNPA1 and hnRNPK, with characteristic changes in nucleocytoplasmic localisation in an RBP-dependent manner. Interestingly, we found that RBPs displayed stress-dependent characteristics, with unique responses to both heat and oxidative stress. Alongside nucleocytoplasmic protein distribution changes, we identified the formation of stress- and RBP-specific nuclear and cytoplasmic foci. Furthermore, the kinetics of nuclear relocalisation upon recovery from extrinsic stressors was also found to be both stress- and RBP-specific. Importantly, these experiments specifically highlight TDP-43 and FUS, two of the most recognised RBPs in ALS pathogenesis, as exhibiting delayed nuclear relocalisation following stress in healthy human motor neurons as compared to SFPQ, hnRNPA1 and hnRNPK. Notably, ALS-causing valosin containing protein (VCP) mutations did not disrupt the relocalisation dynamics of TDP-43 or FUS in human motor neurons following stress. An increased duration of TDP-43 and FUS within the cytoplasm after stress may render the environment more aggregation-prone, which may be poorly tolerated in the context of ALS and related neurodegenerative disorders. In summary, our study addresses stress-specific spatiotemporal responses of neurodegeneration-related RBPs in human motor neurons. The insights into the nucleocytoplasmic dynamics of RBPs provided here may be informative for future studies examining both disease mechanisms and therapeutic strategy

    The translational potential of human induced pluripotent stem cells for clinical neurology: The translational potential of hiPSCs in neurology

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    The induced pluripotent state represents a decade-old Nobel prize-winning discovery. Human-induced pluripotent stem cells (hiPSCs) are generated by the nuclear reprogramming of any somatic cell using a variety of established but evolving methods. This approach offers medical science unparalleled experimental opportunity to model an individual patient's disease "in a dish." HiPSCs permit developmentally rationalized directed differentiation into any cell type, which express donor cell mutation(s) at pathophysiological levels and thus hold considerable potential for disease modeling, drug discovery, and potentially cell-based therapies. This review will focus on the translational potential of hiPSCs in clinical neurology and the importance of integrating this approach with complementary model systems to increase the translational yield of preclinical testing for the benefit of patients. This strategy is particularly important given the expected increase in prevalence of neurodegenerative disease, which poses a major burden to global health over the coming decades

    The microglial component of amyotrophic lateral sclerosis

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    Microglia are the primary immune cells of the CNS, carrying out key homeostatic roles and undergoing context-dependent and temporally regulated changes in response to injury and neurodegenerative diseases. Microglia have been implicated in playing a role in amyotrophic lateral sclerosis (ALS), a neurodegenerative disease characterized by extensive motor neuron loss leading to paralysis and premature death. However, as the pathomechansims of ALS are increasingly recognized to involve a multitude of different cell types, it has been difficult to delineate the specific contribution of microglia to disease. Here, we review the literature of microglial involvement in ALS and discuss the evidence for the neurotoxic and neuroprotective pathways that have been attributed to microglia in this disease. We also discuss accumulating evidence for spatiotemporal regulation of microglial activation in this context. A deeper understanding of the role of microglia in the ‘cellular phase’ of ALS is crucial in the development of mechanistically rationalized therapies

    Decoding the relationship between ageing and amyotrophic lateral sclerosis: a cellular perspective

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    With an ageing population comes an inevitable increase in the prevalence of age-associated neurodegenerative diseases, such as amyotrophic lateral sclerosis (ALS), a relentlessly progressive and universally fatal disease characterized by the degeneration of upper and lower motor neurons within the brain and spinal cord. Indeed, the physiological process of ageing causes a variety of molecular and cellular phenotypes. With dysfunction at the neuromuscular junction implicated as a key pathological mechanism in ALS, and each lower motor unit cell type vulnerable to its own set of age-related phenotypes, the effects of ageing might in fact prove a prerequisite to ALS, rendering the cells susceptible to disease-specific mechanisms. Moreover, we discuss evidence for overlap between age and ALS-associated hallmarks, potentially implicating cell type-specific ageing as a key contributor to this multifactorial and complex disease. With a dearth of disease-modifying therapy currently available for ALS patients and a substantial failure in bench to bedside translation of other potential therapies, the unification of research in ageing and ALS requires high fidelity models to better recapitulate age-related human disease and will ultimately yield more reliable candidate therapeutics for patients, with the aim of enhancing healthspan and life expectancy

    Region-specific vulnerability in neurodegeneration: lessons from normal ageing

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    A number of age-associated neurodegenerative diseases, including Alzheimer’s disease (AD), Parkinson’s disease (PD) and amyotrophic lateral sclerosis (ALS), possess a shared characteristic of region-specific neurodegeneration. However, the mechanisms which determine why particular regions within the nervous system are selectively vulnerable to neurodegeneration, whilst others remain relatively unaffected throughout disease progression, remain elusive. Here, we review how regional susceptibility to the ubiquitous physiological phenomenon of normal ageing might underlie the vulnerability of these same regions to neurodegeneration, highlighting three regions archetypally associated with AD, PD and ALS (the hippocampus, substantia nigra pars compacta and ventral spinal cord, respectively), as especially prone to age-related alterations. Placing particular emphasis on these three regions, we comprehensively explore differential regional susceptibility to nervous system tissue, cellular and molecular level ageing to provide an integrated perspective on why age-related neurodegenerative diseases exhibit region-selective vulnerability. Combining these principles with increasingly recognised differences between chronological and biological ageing (termed differential or ‘delta’ ageing) might ultimately guide therapeutic approaches for these devastating neurodegenerative diseases, for which a paucity of disease modifying and/or life promoting treatments currently exist

    The interplay of rna binding proteins, oxidative stress and mitochondrial dysfunction in als

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    RNA binding proteins fulfil a wide number of roles in gene expression. Multiple mechanisms of RNA binding protein dysregulation have been implicated in the pathomechanisms of several neurodegenerative diseases including amyotrophic lateral sclerosis (ALS). Oxidative stress and mitochondrial dysfunction also play important roles in these diseases. In this review, we high-light the mechanistic interplay between RNA binding protein dysregulation, oxidative stress and mitochondrial dysfunction in ALS. We also discuss different potential therapeutic strategies targeting these pathways

    Chloroquine, the Coronavirus Crisis, and Neurodegeneration: A Perspective

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    On the verge of the ongoing coronavirus pandemic, in vitro data suggested that chloroquine, and its analog hydroxychloroquine, may be useful in controlling SARS-CoV-2 infection. Efforts are ongoing in order to test this hypothesis in clinical trials. Some studies demonstrated no evidence of efficacy, whereas in some cases results were retracted after reporting. Despite the lack of scientific validation, support for the use of these compounds continues from various influencers. At the cellular level, the lysosomotropic drug chloroquine accumulates in acidic organelles where it acts as an alkalizing agent with possible downstream effects on several cellular pathways. In this perspective, we discuss a possible modulatory role of these drugs in two shared features of neurodegenerative diseases, the cellular accumulation of aberrantly folded proteins and the contribution of neuroinflammation in this pathogenic process. Certainly, the decision on the use of chloroquine must be determined by its efficacy in the specific clinical situation. However, at an unprecedented time of a potential widespread use of chloroquine, we seek to raise awareness of its potential impact in ongoing clinical trials evaluating disease-modifying therapies in neurodegeneration

    Hubungan Pengetahuan Dengan Tingkat Kecemasan Pada Klien Pre Operasi Katarak Di Balai Kesehatan Mata Masyarakat (Bkmm) Manado

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    ; Cataracts are opacities in the lens or loss of transparency of the lens resulting in a decrease in visual acuity. Which may occur as a result of hydration (fluid replenishment) lens, lens protein denaturation, or both, someone who had a cataract becomes hazy or blurred vision. One treatment of cataracts is surgery or surgery that often cause anxiety. One of the measures to reduce the level of anxiety is to prepare mentally from the patient. This research is analytic survey with cross-sectional approach, namely the relationship of knowledge to the level of anxiety in the client pre cataract surgery. This study aimed to determine the relationship of knowledge to the level of anxiety in the client pre cataract surgery. This research was conducted in Community Eye Health Center on 09 June to June 23, 2014 with a population of 75 people and the sample in this study amounted to 42 respondents. How to sampling by means of accidental sampling by using a list of questions (questionnaire). Research results with chi-square test assay values obtained α of 0.001 is smaller than α = 0.05. This shows that there is a significant relationship between knowledge with clients preoperative anxiety levels cataract, conclusion of this study is found that respondents who do not have anxiety with both existing Knowledgeable 2 (4.8%), respondents who have mild anxiety with knowledge well there are 15 persons (35.7%), respondents who have moderate anxiety with good knowledge there are 10 persons (23.8%), it can be concluded health education can reduce anxiety and increase knowledge in the preoperative cataract patients. This study nursing profession is expected to provide input for the nursing profession in developing an understanding of the client overcome anxiety preoperative catarac

    Image-based deep learning reveals the responses of human motor neurons to stress and VCP-related ALS

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    OBJECTIVES: Although morphological attributes of cells and their substructures are recognized readouts of physiological or pathophysiological states, these have been relatively understudied in amyotrophic lateral sclerosis (ALS) research. MATERIALS AND METHODS: In this study, we integrate multichannel fluorescence high-content microscopy data with deep-learning imaging methods to reveal - directly from unsegmented images - novel neurite-associated morphological perturbations associated with (ALS-causing) VCP-mutant human motor neurons (MNs). RESULTS: Surprisingly, we reveal that previously unrecognized disease-relevant information is withheld in broadly used and often considered 'generic' biological markers of nuclei (DAPI) and neurons (β III-tubulin). Additionally, we identify changes within the information content of ALS-related RNA binding protein (RBP) immunofluorescence imaging that is captured in VCP-mutant MN cultures. Furthermore, by analysing MN cultures exposed to different extrinsic stressors, we show that heat stress recapitulates key aspects of ALS. CONCLUSIONS: Our study therefore reveals disease-relevant information contained in a range of both generic and more specific fluorescent markers, and establishes the use of image-based deep learning methods for rapid, automated and unbiased identification of biological hypotheses
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