78 research outputs found

    The role of inclusions in ALS pathogenesis

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    Amyotrophic lateral sclerosis (ALS) is a devastating neurodegenerative disease that primarily afflicts motor neurons, leading to paralysis and death within 3 to 5 years after diagnosis. Genetic studies have uncovered multiple genetic defects causing familial forms of ALS and mutations occurring in proteins with a variety of functions, including RNA metabolism (TDP43, FUS) and oxygen free radical homeostasis (SOD1). A commonality among all ALS forms is the presence of intracellular inclusions that primarily consist of insoluble protein aggregates. These inclusions indicate that protein aggregation is a central pathogenic event shared by multiple ALS forms. The research of the present thesis focuses on the role of protein aggregation and inclusion formation in two types of ALS: 1) ALS caused by mutations in the superoxide dismutase 1 (SOD1) gene (ALS1); and 2) ALS caused by mutations in the vesicle-associated membrane protein (VAMP)-associated protein B (VAPB) gene (ALS8)

    Amyotrophic lateral sclerosis (ALS)-associated VAPB-P56S inclusions represent an ER quality control compartment

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    BACKGROUND: Protein aggregation and the formation of intracellular inclusions are a central feature of many neurodegenerative disorders, but precise knowledge about their pathogenic role is lacking in most instances. Here we have characterized inclusions formed in transgenic mice carrying the P56S mutant form of VAPB that causes various motor neuron syndromes including ALS8.RESULTS: Inclusions in motor neurons of VAPB-P56S transgenic mice are characterized by the presence of smooth ER-like tubular profiles, and are immunoreactive for factors that operate in the ER associated degradation (ERAD) pathway, including p97/VCP, Derlin-1, and the ER membrane chaperone BAP31. The presence of these inclusions does not correlate with signs of axonal and neuronal degeneration, and axotomy leads to their gradual disappearance, indicating that they represent reversible structures. Inhibition of the proteasome and knockdown of the ER membrane chaperone BAP31 increased the size of mutant VAPB inclusions in primary neuron cultures, while knockdown of TEB4, an ERAD ubiquitin-protein ligase, reduced their size. Mutant VAPB did not codistribute with mutant forms of seipin that are associated with an autosomal dominant motor neuron disease, and accumulate in a protective ER derived compartment termed ERPO (ER protective organelle) in neurons.CONCLUSIONS: The data indicate that the VAPB-P56S inclusions represent a novel reversible ER quality control compartment that is formed when the amount of mutant VAPB exceeds the capacity of the ERAD pathway and that isolates misfolded and aggregated VAPB from the rest of the ER. The presence of this quality control compartment reveals an additional level of flexibility of neurons to cope with misfolded protein stress in the ER

    Suffering in long-term cancer survivors: An evaluation of the PRISM-R2 in a population-based cohort

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    The Pictorial Representation of Illness and Self Measure-Revised 2 (PRISM-R2) has been developed as generic measure to assess suffering. The aim of this study was to evaluate the ability of this instrument to identify long-term cancer survivors with high levels of suffering who may need additional support. 1299 cancer survivors completed the PRISM-R2, the Short Form Health Survey (SF-36), and the Quality of Life-Cancer Survivors questionnaire (QoL-CS). The PRISM-R2 distinguishes between the Self-Illness Separation (SIS) and Illness Perception Measure (IPM), both measuring aspects of suffering. 112 (9%) cancer survivors reported high suffering according to IPM. This group had a higher cancer stage at diagnosis, more cancer recurrences, more comorbidities, and were lower educated compared to people reporting less suffering. The PRISM-R2 could explain substantial amounts of variance (10-14%) in the psychological aspects of the SF-36 and QoL-CS. The IPM also discriminated statistically and clinically significant between high- and low-health status. The PRISM-R2 proved to be able to discriminate between individuals with good and deteriorated levels of QoL. Further evaluation of its validity and screening potential is recommended

    The impact of disease progression on perceived health status and quality of life of long-term cancer survivors

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    Introduction The number of cancer survivors experiencing disease progression (DP) is increasing with the number of cancer survivors. However, little is known whether DP affects health-related quality of life (HRQL) of long-term cancer survivors. We aimed therefore to compare the health status (HS) and HRQL of DP and disease-free (DF) survivors up to 15 years after initial diagnosis. Methods 232 cancer survivors with DP identified through the Eindhoven Cancer Registry were matched with 232 DF survivors of similar demographic and clinical characteristics. Patients completed generic HS (SF-36) and cancer-specific HRQL (QOL-CS) questionnaires 5-15 years after diagnosis. Results Compared with DF survivors, DP survivors exhibited significantly lower scores on all SF-36 and QOL-CS (except spiritual well-being) dimensions. DF survivors had better scores than the normative population on all SF-36 dimensions. Among survivors with DP, those with short survival (<5 years) had significantly poorer HS scores on all dimensions except bodily pain compared with the normative population. Comparatively, the long survival (≄5 years) DP group had better HRQL than the short DP group but poorer HRQL than the normative population. In multivariate analyses, DP and DF survival time were independently associated with aspects of HS and HRQL in cancer survivors. Discussions/Conclusions DP cancer survivors have poorer long-term HS and HRQL compared with DF survivors. However, there is suggestion that HS and HRQL does improve over time following DP. Implication for Cancer Survivors Although DP survivors report poorer long-term HRQL compared with DF cancer survivors, results suggest that time can attenuate the distress of DP on HRQL. Psycho-educational programs could help to increase patients' sense of empowerment and personal control should DP occur

    Cardiometabolic effects of genetic upregulation of the interleukin 1 receptor antagonist: a Mendelian randomisation analysis

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    Background To investigate potential cardiovascular and other effects of long-term pharmacological interleukin 1 (IL-1) inhibition, we studied genetic variants that produce inhibition of IL-1, a master regulator of inflammation. Methods We created a genetic score combining the effects of alleles of two common variants (rs6743376 and rs1542176) that are located upstream of IL1RN, the gene encoding the IL-1 receptor antagonist (IL-1Ra; an endogenous inhibitor of both IL-1 alpha and IL-1 beta); both alleles increase soluble IL-1Ra protein concentration. We compared effects on inflammation biomarkers of this genetic score with those of anakinra, the recombinant form of IL-1Ra, which has previously been studied in randomised trials of rheumatoid arthritis and other inflammatory disorders. In primary analyses, we investigated the score in relation to rheumatoid arthritis and four cardiometabolic diseases (type 2 diabetes, coronary heart disease, ischaemic stroke, and abdominal aortic aneurysm; 453 411 total participants). In exploratory analyses, we studied the relation of the score to many disease traits and to 24 other disorders of proposed relevance to IL-1 signalling (746 171 total participants). Findings For each IL1RN minor allele inherited, serum concentrations of IL-1Ra increased by 0.22 SD (95% CI 0.18-0.25; 12.5%; p=9.3 x 10(-33)), concentrations of interleukin 6 decreased by 0.02 SD (-0.04 to -0.01; -1,7%; p=3.5 x 10(-3)), and concentrations of C-reactive protein decreased by 0.03 SD (-0.04 to -0.02; -3.4%; p=7.7 x 10(-14)). We noted the effects of the genetic score on these inflammation biomarkers to be directionally concordant with those of anakinra. The allele count of the genetic score had roughly log-linear, dose-dependent associations with both IL-1Ra concentration and risk of coronary heart disease. For people who carried four IL-1Ra-raising alleles, the odds ratio for coronary heart disease was 1.15 (1.08-1.22; p=1.8 x 10(-6)) compared with people who carried no IL-1Ra-raising alleles; the per-allele odds ratio for coronary heart disease was 1.03 (1.02-1.04; p=3.9 x 10(-10)). Perallele odds ratios were 0.97 (0.95-0.99; p=9.9 x 10(-4)) for rheumatoid arthritis, 0.99 (0.97-1.01; p=0.47) for type 2 diabetes, 1.00 (0.98-1.02; p=0.92) for ischaemic stroke, and 1.08 (1.04-1.12; p=1.8 x 10(-5)) for abdominal aortic aneurysm. In exploratory analyses, we observed per-allele increases in concentrations of proatherogenic lipids, including LDL-cholesterol, but no clear evidence of association for blood pressure, glycaemic traits, or any of the 24 other disorders studied. Modelling suggested that the observed increase in LDL-cholesterol could account for about a third of the association observed between the genetic score and increased coronary risk. Interpretation Human genetic data suggest that long-term dual IL-1 alpha/beta inhibition could increase cardiovascular risk and, conversely, reduce the risk of development of rheumatoid arthritis. The cardiovascular risk might, in part, be mediated through an increase in proatherogenic lipid concentrations. Copyright (C) The Interleukin 1 Genetics Consortium. Open Access article distributed under the terms of CC-BY-NC-ND

    Moving beyond neurons: the role of cell type-specific gene regulation in Parkinson's disease heritability

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    Parkinson’s disease (PD), with its characteristic loss of nigrostriatal dopaminergic neurons and deposition of α-synuclein in neurons, is often considered a neuronal disorder. However, in recent years substantial evidence has emerged to implicate glial cell types, such as astrocytes and microglia. In this study, we used stratified LD score regression and expression-weighted cell-type enrichment together with several brain-related and cell-type-specific genomic annotations to connect human genomic PD findings to specific brain cell types. We found that PD heritability attributable to common variation does not enrich in global and regional brain annotations or brain-related cell-type-specific annotations. Likewise, we found no enrichment of PD susceptibility genes in brain-related cell types. In contrast, we demonstrated a significant enrichment of PD heritability in a curated lysosomal gene set highly expressed in astrocytic, microglial, and oligodendrocyte subtypes, and in LoF-intolerant genes, which were found highly expressed in almost all tested cellular subtypes. Our results suggest that PD risk loci do not lie in specific cell types or individual brain regions, but rather in global cellular processes detectable across several cell types

    Trapping in irradiated p-on-n silicon sensors at fluences anticipated at the HL-LHC outer tracker

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    The degradation of signal in silicon sensors is studied under conditions expected at the CERN High-Luminosity LHC. 200 ÎŒ\mum thick n-type silicon sensors are irradiated with protons of different energies to fluences of up to 3⋅10153 \cdot 10^{15} neq/cm2^2. Pulsed red laser light with a wavelength of 672 nm is used to generate electron-hole pairs in the sensors. The induced signals are used to determine the charge collection efficiencies separately for electrons and holes drifting through the sensor. The effective trapping rates are extracted by comparing the results to simulation. The electric field is simulated using Synopsys device simulation assuming two effective defects. The generation and drift of charge carriers are simulated in an independent simulation based on PixelAV. The effective trapping rates are determined from the measured charge collection efficiencies and the simulated and measured time-resolved current pulses are compared. The effective trapping rates determined for both electrons and holes are about 50% smaller than those obtained using standard extrapolations of studies at low fluences and suggests an improved tracker performance over initial expectations

    Genome-wide bidirectional CRISPR screens identify mucins as host factors modulating SARS-CoV-2 infection

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    Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes a range of symptoms in infected individuals, from mild respiratory illness to acute respiratory distress syndrome. A systematic understanding of host factors influencing viral infection is critical to elucidate SARS-CoV-2–host interactions and the progression of Coronavirus disease 2019 (COVID-19). Here, we conducted genome-wide CRISPR knockout and activation screens in human lung epithelial cells with endogenous expression of the SARS-CoV-2 entry factors ACE2 and TMPRSS2. We uncovered proviral and antiviral factors across highly interconnected host pathways, including clathrin transport, inflammatory signaling, cell-cycle regulation, and transcriptional and epigenetic regulation. We further identified mucins, a family of high molecular weight glycoproteins, as a prominent viral restriction network that inhibits SARS-CoV-2 infection in vitro and in murine models. These mucins also inhibit infection of diverse respiratory viruses. This functional landscape of SARS-CoV-2 host factors provides a physiologically relevant starting point for new host-directed therapeutics and highlights airway mucins as a host defense mechanism
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