35 research outputs found

    Myeloid cell iron uptake pathways and paramagnetic rim formation in multiple sclerosis

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    In multiple sclerosis (MS), sustained inflammatory activity can be visualized by iron-sensitive magnetic resonance imaging (MRI) at the edges of chronic lesions. These paramagnetic rim lesions (PRLs) are associated with clinical worsening, although the cell type-specific and molecular pathways of iron uptake and metabolism are not well known. We studied two postmortem cohorts: an exploratory formalin-fixed paraffin-embedded (FFPE) tissue cohort of 18 controls and 24 MS cases and a confirmatory snap-frozen cohort of 6 controls and 14 MS cases. Besides myelin and non-heme iron imaging, the haptoglobin-hemoglobin scavenger receptor CD163, the iron-metabolizing markers HMOX1 and HAMP as well as immune-related markers P2RY12, CD68, C1QA and IL10 were visualized in myeloid cell (MC) subtypes at RNA and protein levels across different MS lesion areas. In addition, we studied PRLs in vivo in a cohort of 98 people with MS (pwMS) via iron-sensitive 3 T MRI and haptoglobin genotyping by PCR. CSF samples were available from 38 pwMS for soluble CD163 (sCD163) protein level measurements by ELISA. In postmortem tissues, we observed that iron uptake was linked to rim-associated C1QA-expressing MC subtypes, characterized by upregulation of CD163, HMOX1, HAMP and, conversely, downregulation of P2RY12. We found that pwMS with [Formula: see text] 4 PRLs had higher sCD163 levels in the CSF than pwMS with [Formula: see text] 3 PRLs with sCD163 correlating with the number of PRLs. The number of PRLs was associated with clinical worsening but not with age, sex or haptoglobin genotype of pwMS. However, pwMS with Hp2-1/Hp2-2 haplotypes had higher clinical disability scores than pwMS with Hp1-1. In summary, we observed upregulation of the CD163-HMOX1-HAMP axis in MC subtypes at chronic active lesion rims, suggesting haptoglobin-bound hemoglobin but not transferrin-bound iron as a critical source for MC-associated iron uptake in MS. The correlation of CSF-associated sCD163 with PRL counts in MS highlights the relevance of CD163-mediated iron uptake via haptoglobin-bound hemoglobin. Also, while Hp haplotypes had no noticeable influence on PRL counts, pwMS carriers of a Hp2 allele might have a higher risk to experience clinical worsening

    Distributed changes of the functional connectome in patients with glioblastoma

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    Glioblastoma might have widespread effects on the neural organization and cognitive function, and even focal lesions may be associated with distributed functional alterations. However, functional changes do not necessarily follow obvious anatomical patterns and the current understanding of this interrelation is limited. In this study, we used resting-state functional magnetic resonance imaging to evaluate changes in global functional connectivity patterns in 15 patients with glioblastoma. For six patients we followed longitudinal trajectories of their functional connectome and structural tumour evolution using bi-monthly follow-up scans throughout treatment and disease progression. In all patients, unilateral tumour lesions were associated with inter-hemispherically symmetric network alterations, and functional proximity of tumour location was stronger linked to distributed network deterioration than anatomical distance. In the longitudinal subcohort of six patients, we observed patterns of network alterations with initial transient deterioration followed by recovery at first follow-up, and local network deterioration to precede structural tumour recurrence by two months. In summary, the impact of focal glioblastoma lesions on the functional connectome is global and linked to functional proximity rather than anatomical distance to tumour regions. Our findings further suggest a relevance for functional network trajectories as a possible means supporting early detection of tumour recurrence

    Non‐interventional, prospective, observational study on spasticity‐associated symptom control with nabiximols as add‐on therapy in patients with multiple sclerosis spasticity in Austria

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    Abstract Background and purpose Randomized controlled trials and observational studies of nabiximols oromucosal spray in patients with multiple sclerosis (MS) spasticity have shown improvement in a range of associated symptoms (pain, spasms, fatigue, bladder dysfunction, and sleep disturbances). This study evaluated the effectiveness and tolerability of add‐on nabiximols in the routine management of patients with MS spasticity in Austria, with a focus on spasticity‐associated symptoms. Methods This was an open, prospective, multicenter, observational, non‐interventional study of patients with MS spasticity receiving add‐on treatment with nabiximols oromucosal spray. Main endpoints were patient‐reported changes from baseline in the frequency (counts) or severity (mean Numerical Rating Scale [NRS] scores) of spasticity‐associated symptoms, and patient‐reported changes from baseline in impairment of daily activities due to spasticity, after 1 and 3 months of nabiximols treatment. No analyses were conducted for statistical significance. Results There were 55 patients in the effectiveness population, and 62 in the safety population. Patients reported clinically relevant reductions from baseline to month 3 in the average number of spasms/day (−68.2%) and number of urinary incontinence episodes (−69.3%) in the week prior to the clinic visit, and reductions in mean 0−10 NRS scores for sleep impairment (−47.2%), fatigue (−26.4%), pain (40.4%), and spasticity severity (39.0%). There was no change from baseline in daily activity impairment due to spasticity. The majority of patients were at least partly satisfied with add‐on nabiximols for spasticity‐associated symptoms. There were 31 adverse events (27 treatment related) reported in 19 patients, with no new safety signals. Conclusions Add‐on nabiximols improved the severity of MS spasticity and a range of spasticity‐associated symptoms during real‐world use in Austria. Nabiximols is an option for patients with MS spasticity who fail first‐line oral antispasticity treatment

    Exome-sequence analyses of four multi-incident multiple sclerosis families

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    Multiple sclerosis (MS) is an inflammatory demyelinating disease of the Central Nervous System (CNS). Currently, it is estimated that 30–40% of the phenotypic variability of MS can be explained by genetic factors. However, low susceptibility variants identified through Genome Wide Association Study (GWAS) were calculated to explain about 50% of the heritability. Whether familial high-risk variants also contribute to heritability is a subject of controversy. In the last few years, several familial variants have been nominated, but none of them have been unequivocally confirmed. One reason for this may be that genetic heterogeneity and reduced penetrance are hindering detection. Sequencing a large number of MS families is needed to answer this question. In this study, we performed whole exome sequencing in four multi-case families, of which at least three affected individuals per family were analyzed. We identified a total of 138 rare variants segregating with disease in each of the families. Although no single variant showed convincing evidence for disease causation, some genes seemed particularly interesting based on their biological function. The main aim of this study was to provide a complete list of all rare segregating variants to provide the possibility for other researchers to cross-check familial candidate genes in an unbiased manner
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