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Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disorder affecting motor neurons, with a typical lifespan of 3-5 years. Altered metabolism is a key feature of ALS that strongly influences prognosis, with an increase in whole body energy expenditure and changes in skeletal muscle metabolism, including greater reliance on fat oxidation. Dyslipidaemia has been described in ALS as part of the metabolic dysregulation, but its role in the pathophysiology of the disease remains controversial. Among the lipids, cholesterol is of particular interest as a vital component of cell membranes, playing a key role in signal transduction and mitochondrial function in muscle. The aim of this study was to investigate whether motor dysfunction in ALS might be associated with dysregulation of muscle cholesterol metabolism. We determined cholesterol content and analysed the expression of key determinants of the cholesterol metabolism pathway in muscle biopsies from 13 ALS patients and 10 asymptomatic ALS-mutation gene carriers compared to 16 control subjects. Using human control primary myotubes, we investigated the potential contribution of cholesterol dyshomeostasis to reliance on mitochondrial fatty acid. We found that cholesterol accumulates in the skeletal muscle of ALS patients and that cholesterol overload significantly correlates with disease severity evaluated by the Revised ALS Functional Rating Scale. These defects are associated with overexpression of the genes of the lysosomal cholesterol transporters Niemann-Pick type C1 (NPC1) and 2 (NPC2), which are required for cholesterol transfer from late endosomes/lysosomes to cellular membranes. Most notably, a significant increase in NPC2 mRNA levels could be detected in muscle samples from asymptomatic ALS-mutation carriers, long before disease onset. We found that filipin-stained unesterified cholesterol accumulated in the lysosomal compartment in ALS muscle samples, suggesting dysfunction of the NPC1/2 system. Accordingly, we report here that experimental NPC1 inhibition or lysosomal pH alteration in human primary myotubes was sufficient to induce the overexpression of NPC1 and NPC2 mRNA. Finally, acute NPC1 inhibition in human control myotubes induced a shift towards a preferential use of fatty acids, thus reproducing the metabolic defect characteristic of ALS muscle. We conclude that cholesterol homeostasis is dysregulated in ALS muscle from the presymptomatic stage. Targeting NPC1/2 dysfunction may be a new therapeutic strategy for ALS to restore muscle energy metabolism and slow motor symptom progression., (© The Author(s) 2024. Published by Oxford University Press on behalf of the Guarantors of Brain.)

Background: Thoracic disc herniation is relatively uncommon, accounting for less than 1% of all spinal herniations. Although most often asymptomatic, they may represent a rare cause of spinal cord ischemia., Case Report: We report the case of a healthy 43-year-old North African male who presented with a Brown-Sequard syndrome revealing a spinal cord ischemia caused by a thoracic disc extrusion. The initial MRI revealed a calcified disc extrusion at the level of T5-T6 without significant spinal cord compression or signal abnormality. A pattern consistent with a medullary ischemia only appeared 48 h later. The patient was treated conservatively with Aspirin and Heparin, which were discontinued later because of a negative cardiovascular work-up. The calcified disc extrusion, which was later recognized as the cause of the ischemia, decreased spontaneously over time and the patient recovered within a few months., Conclusions: Our case highlights the challenge in diagnosing and managing this uncommon condition. We propose a literature review showing the different therapeutic strategies and their corresponding clinical outcomes., (© 2023. The Author(s).)

Background and Objectives: Spinal muscular atrophy (SMA) is mainly caused by homozygous SMN1 gene deletions on 5q13. Non-5q SMA patients' series are lacking, and the diagnostic yield of next-generation sequencing (NGS) is largely unknown. The aim of this study was to describe the clinical and genetic landscape of non-5q SMA and evaluate the performance of neuropathy gene panels in these disorders., Methods: Description of patients with non-5q SMA followed in the different neuromuscular reference centers in France as well as in London, United Kingdom. Patients without a genetic diagnosis had undergone at least a neuropathy or large neuromuscular gene panel., Results: Seventy-one patients from 65 different families were included, mostly sporadic cases (60.6%). At presentation, 21 patients (29.6%) showed exclusive proximal weakness (P-SMA), 35 (49.3%) showed associated distal weakness (PD-SMA), and 15 (21.1%) a scapuloperoneal phenotype (SP-SMA). Thirty-two patients (45.1%) had a genetic diagnosis: BICD2 (n = 9), DYNC1H1 (n = 7), TRPV4 (n = 4), VCP , HSBP1 , AR (n = 2), VRK1 , DNAJB2 , MORC2 , ASAH1 , HEXB , and unexpectedly, COL6A3 (n = 1). The genetic diagnostic yield was lowest in P-SMA (6/21, 28.6%) compared with PD-SMA (16/35, 45.7%) and SP-SMA (10/15, 66.7%). An earlier disease onset and a family history of the disease or consanguinity were independent predictors of a positive genetic diagnosis. Neuropathy gene panels were performed in 59 patients with a 32.2% diagnostic yield (19/59). In 13 additional patients, a genetic diagnosis was achieved through individual gene sequencing or an alternative neuromuscular NGS., Discussion: Non-5q SMA is genetically heterogeneous, and neuropathy gene panels achieve a molecular diagnosis in one-third of the patients. The diagnostic yield can be increased by sequencing of other neuromuscular and neurometabolic genes. Nevertheless, there is an unmet need to cluster these patients to aid in the identification of new genes., Competing Interests: The authors report no relevant disclosures. Go to Neurology.org/NG for full disclosures., (Copyright © 2023 The Author(s). Published by Wolters Kluwer Health, Inc. on behalf of the American Academy of Neurology.)

Background: CAG-repeat expansions in Ataxin 2 ( ATXN2 ) are known to cause spinocerebellar ataxia type 2 (SCA2), but CAA interrupted expansions may also result in autosomal dominant Parkinson's disease (AD PD). However, because of technical limitations, such expansions are not explored in whole exome sequencing (WES) data., Objectives: To identify ATXN2 expansions using WES data from PD cases., Methods: We explored WES data from a cohort of 477 index cases with PD using ExpansionHunter (Illumina DRAGEN Bio-IT Platform, San Diego, CA). Putative expansions were confirmed by combining polymerase chain reaction and fragment length analysis followed by sub-cloning and sequencing methods., Results: Using ExpansionHunter, we identified three patients from two families with AD PD carrying either ATXN2 22/39 or 22/37 repeats, both interrupted by four CAA repeats., Conclusion: These findings demonstrate the usefulness of WES to detect pathogenic CAG repeat expansions, which were found in 1.7% of AD PD in the ATXN2 gene in our exome dataset., (© 2023 The Authors. Movement Disorders Clinical Practice published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.)

Background: The cause of the motor neuron (MN) death that drives terminal pathology in amyotrophic lateral sclerosis (ALS) remains unknown, and it is thought that the cellular environment of the MN may play a key role in MN survival. Several lines of evidence implicate vesicles in ALS, including that extracellular vesicles may carry toxic elements from astrocytes towards MNs, and that pathological proteins have been identified in circulating extracellular vesicles of sporadic ALS patients. Because MN degeneration at the neuromuscular junction is a feature of ALS, and muscle is a vesicle-secretory tissue, we hypothesized that muscle vesicles may be involved in ALS pathology., Methods: Sporadic ALS patients were confirmed to be ALS according to El Escorial criteria and were genotyped to test for classic gene mutations associated with ALS, and physical function was assessed using the ALSFRS-R score. Muscle biopsies of either mildly affected deltoids of ALS patients (n = 27) or deltoids of aged-matched healthy subjects (n = 30) were used for extraction of muscle stem cells, to perform immunohistology, or for electron microscopy. Muscle stem cells were characterized by immunostaining, RT-qPCR, and transcriptomic analysis. Secreted muscle vesicles were characterized by proteomic analysis, Western blot, NanoSight, and electron microscopy. The effects of muscle vesicles isolated from the culture medium of ALS and healthy myotubes were tested on healthy human-derived iPSC MNs and on healthy human myotubes, with untreated cells used as controls., Results: An accumulation of multivesicular bodies was observed in muscle biopsies of sporadic ALS patients by immunostaining and electron microscopy. Study of muscle biopsies and biopsy-derived denervation-naïve differentiated muscle stem cells (myotubes) revealed a consistent disease signature in ALS myotubes, including intracellular accumulation of exosome-like vesicles and disruption of RNA-processing. Compared with vesicles from healthy control myotubes, when administered to healthy MNs the vesicles of ALS myotubes induced shortened, less branched neurites, cell death, and disrupted localization of RNA and RNA-processing proteins. The RNA-processing protein FUS and a majority of its binding partners were present in ALS muscle vesicles, and toxicity was dependent on the expression level of FUS in recipient cells. Toxicity to recipient MNs was abolished by anti-CD63 immuno-blocking of vesicle uptake., Conclusions: ALS muscle vesicles are shown to be toxic to MNs, which establishes the skeletal muscle as a potential source of vesicle-mediated toxicity in ALS., (© 2022 The Authors. Journal of Cachexia, Sarcopenia and Muscle published by John Wiley & Sons Ltd on behalf of Society on Sarcopenia, Cachexia and Wasting Disorders.)

Objective: The aim of this study was the comprehensive characterisation of longitudinal clinical, electrophysiological and neuroimaging measures in type III and IV adult spinal muscular atrophy (SMA) with a view to propose objective monitoring markers for future clinical trials., Methods: Fourteen type III or IV SMA patients underwent standardised assessments including muscle strength testing, functional evaluation (SMAFRS and MFM), MUNIX (abductor pollicis brevis, APB; abductor digiti minimi, ADM; deltoid; tibialis anterior, TA; trapezius) and quantitative cervical spinal cord MRI to appraise segmental grey and white matter atrophy. Patients underwent a follow-up assessment with the same protocol 24 months later. Longitudinal comparisons were conducted using the Wilcoxon-test for matched data. Responsiveness was estimated using standardized response means (SRM) and a composite score was generated based on the three most significant variables., Results: Significant functional decline was observed based on SMAFRS (p = 0.019), pinch and knee flexion strength (p = 0.030 and 0.027), MUNIX and MUSIX value in the ADM (p = 0.0006 and 0.043) and in TA muscle (p = 0.025). No significant differences were observed based on cervical MRI measures. A significant reduction was detected in the composite score (p = 0.0005, SRM = -1.52), which was the most responsive variable and required a smaller number of patients than single variables in the estimation of sample size for clinical trials., Conclusions: Quantitative strength testing, SMAFRS and MUNIX readily capture disease progression in adult SMA patients. Composite multimodal scores increase predictive value and may reduce sample size requirements in clinical trials.

ANXA11 mutations have previously been discovered in amyotrophic lateral sclerosis (ALS) motor neuron disease. To confirm the contribution of ANXA11 mutations to ALS, a large exome data set obtained from 330 French patients, including 150 familial ALS index cases and 180 sporadic ALS cases, was analyzed, leading to the identification of 3 rare ANXA11 variants in 5 patients. The novel p.L254V variant was associated with early onset sporadic ALS. The novel p.D40Y mutation and the p.G38R variant concerned patients with predominant pyramidal tract involvement and cognitive decline. Neuropathologic findings in a p.G38R carrier associated the presence of ALS typical inclusions within the spinal cord, massive degeneration of the lateral tracts, and type A frontotemporal lobar degeneration. This mutant form of annexin A11 accumulated in various brain regions and in spinal cord motor neurons, although its stability was decreased in patients' lymphoblasts. Because most ANXA11 inclusions were not colocalized with transactive response DNA-binding protein 43 or p62 deposits, ANXA11 aggregation does not seem mandatory to trigger neurodegeneration with additional participants/partner proteins that could intervene., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Due to the expanding use of non-invasive ventilation (NIV) in amyotrophic lateral sclerosis (ALS), the question of enteral nutrition is increasingly raised in NIV users ALS patients. Here, we aimed to determine the prognostic factors for survival after gastrostomy placement in routine NIV users, taking into consideration ventilator dependence. Ninety-two routine NIV users ALS patients, who underwent gastrostomy insertion for severe dysphagia and/or weight loss, were included. We used a Cox proportional hazards model to identify factors affecting survival and compared time from gastrostomy to death and 30-day mortality rate between dependent (daily use ≥ 16 h) and non-dependent NIV users. The hazard of death after gastrostomy was significantly affected by 3 factors: age at onset (HR 1.047, p = 0.006), body mass index < 20 kg/m 2 at the time of gastrostomy placement (HR 2.012, p = 0.016) and recurrent accumulation of airway secretions (HR 2.614, p = 0.001). Mean time from gastrostomy to death was significantly shorter in the dependent than in the non-dependent NIV users group (133 vs. 250 days, p = 0.04). The 30-day mortality rate was significantly higher in dependent NIV users (21.4% vs. 2.8%, p = 0.03). Pre-operative ventilator dependence and airway secretion accumulation are associated with worse prognosis and should be key decision-making criteria when considering gastrostomy tube placement in NIV users ALS patients.

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disorder causing a progressive motor weakness of all voluntary muscles, whose progression challenges communication modalities such as handwriting or speech. The current study investigated whether ALS subjects can use Eye-On-Line (EOL), a novel eye-operated communication device allowing, after training, to voluntarily control smooth-pursuit eye-movements (SPEM) so as to eye-write in cursive. To that aim, ALS participants ( n = 12) with preserved eye-movements but impaired handwriting were trained during six on-site visits. The primary outcome of the study was the recognition of eye-written digits (0-9) from ALS and healthy control subjects by naïve "readers." Changes in oculomotor performance and the safety of EOL were also evaluated. At the end of the program, 69.4% of the eye-written digits from 11 ALS subjects were recognized by naïve readers, similar to the 67.3% found for eye-written digits from controls participants, with however, large inter-individual differences in both groups of "writers." Training with EOL was associated with a transient fatigue leading one ALS subject to drop out the study at the fifth visit. Otherwise, itching eyes was the most common adverse event (3 subjects). This study shows that, despite the impact of ALS on the motor system, most ALS participants could improve their mastering of eye-movements, so as to produce recognizable eye-written digits, although the eye-traces sometimes needed smoothing to ease digit legibility from both ALS subjects and control participants. The capability to endogenously and voluntarily generate eye-traces using EOL brings a novel way to communicate for disabled individuals, allowing creative personal and emotional expression.

Spinal muscular atrophy (SMA) type III and IV are autosomal recessive, slowly progressive lower motor neuron syndromes. Nevertheless, wider cerebral involvement has been consistently reported in mouse models. The objective of this study is the characterisation of spinal and cerebral pathology in adult forms of SMA using multimodal quantitative imaging., Methods: Twenty-five type III and IV adult SMA patients and 25 age-matched healthy controls were enrolled in a spinal cord and brain imaging study. Structural measures of grey and white matter involvement and diffusion parameters of white matter integrity were evaluated at each cervical spinal level. Whole-brain and region-of-interest analyses were also conducted in the brain to explore cortical thickness, grey matter density and tract-based white matter alterations., Results: In the spinal cord, considerable grey matter atrophy was detected between C2-C6 vertebral levels. In the brain, increased grey matter density was detected in motor and extra-motor regions of SMA patients. No white matter pathology was identified neither at brain and spinal level., Conclusions: Adult forms of SMA are associated with selective grey matter degeneration in the spinal cord with preserved white matter integrity. The observed increased grey matter density in the motor cortex may represent adaptive reorganisation., (Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.)

Objective: Amyotrophic lateral sclerosis (ALS) is a fatal and progressive neurodegenerative disorder involving motor neurons of the cerebral cortex, brain stem and spinal cord. Besides the motor signs, cognitive disorders and apathy may be present and may impact the survival time. These elements are therefore to be taken into consideration for medical care because they can influence the disease evolution. The literature shows low psychopathological disorders in this population despite its poor prognosis. The main objective of this study is to explore the emotional feeling in apathetic and non-apathetic patients in relation to their anxiety and depressive symptoms., Methods: We included 152 patients at the day hospital for the follow-up of their illness, with an average age of 61±12.2 years. All filled the following self-administered questionnaires: EPN-31 (emotional feeling), HADS (for anxiety and depressive symptoms) and the Marin's apathy evaluation scale. Most of the patients (n=110) had also a cognitive assessment with the ALS-CBS scale., Results: 42% of patients could be considered as apathetic and they felt both positive and negative emotions whose frequency was related to the presence and intensity of anxiety and depressive symptoms. The only significant differences were that apathetic and anxious patients experienced more negative emotions including sadness, shame and anger than non-apathetic and anxious patients. Apathy was negatively correlated with cognitive functioning and survival time., Conclusions: These results highlighted the negative impact that apathy seemed to have on the evolution of this disease. However, apathetic patients didn't show emotional blunting and were able to name and feel positive and negative emotions; and even feel more negative emotions than non-apathetic patients when they were anxious. A better understanding of apathetic and no apathetic patients' emotional feelings should lead to a more personalized care for the ALS patients.

Objective: Objective of this study is the comprehensive characterisation of motor unit (MU) loss in type III and IV Spinal Muscular Atrophy (SMA) using motor unit number index (MUNIX), and evaluation of compensatory mechanisms based on MU size indices (MUSIX)., Methods: Nineteen type III and IV SMA patients and 16 gender- and age-matched healthy controls were recruited. Neuromuscular performance was evaluated by muscle strength testing and functional scales. Compound motor action potential (CMAP), MUNIX and MUSIX were studied in the abductor pollicis brevis (APB), abductor digiti minimi (ADM), deltoid, tibialis anterior and trapezius muscles. A composite MUNIX score was also calculated., Results: SMA patients exhibited significantly reduced MUNIX values (p < 0.05) in all muscles, while MUSIX was increased, suggesting active re-innervation. Significant correlations were identified between MUNIX/MUSIX and muscle strength. Similarly, composite MUNIX scores correlated with disability scores. Interestingly, in SMA patients MUNIX was much lower in the ADM than in the ABP, a pattern which is distinctly different from that observed in Amyotrophic Lateral Sclerosis., Conclusions: MUNIX is a sensitive measure of MU loss in adult forms of SMA and correlates with disability., Significance: MUNIX evaluation is a promising candidate biomarker for longitudinal studies and pharmacological trials in adult SMA patients., (Copyright © 2018 International Federation of Clinical Neurophysiology. Published by Elsevier B.V. All rights reserved.)

Introduction: Extrapyramidal deficits are poorly characterised in amyotrophic lateral sclerosis (ALS) despite their contribution to functional disability, increased fall risk and their quality-of-life implications. Given the concomitant pyramidal and cerebellar degeneration in ALS, the clinical assessment of extrapyramidal features is particularly challenging., Objective: The comprehensive characterisation of postural instability in ALS using standardised clinical assessments, gait analyses and computational neuroimaging tools in a prospective study design., Methods: Parameters of gait initiation in the anticipatory postural adjustment phase (APA) and execution phase (EP) were evaluated in ALS patients with and without postural instability and healthy controls. Clinical and gait analysis parameters were interpreted in the context of brain imaging findings., Results: ALS patients with postural instability exhibit impaired gait initiation with an altered APA phase, poor dynamic postural control and significantly decreased braking index. Consistent with their clinical profile, "unsteady" ALS patients have reduced caudate and brain stem volumes compared to "steady" ALS patients., Interpretation: Our findings highlight that the ALS functional rating scale (ALSFRS-r) does not account for extrapyramidal deficits, which are major contributors to gait impairment in a subset of ALS patients. Basal ganglia degeneration in ALS does not only contribute to cognitive and behavioural deficits, but also adds to the heterogeneity of motor disability.