Study of motor asymmetry in ALS indicates an effect of limb dominance on onset and spread of weakness, and an important role for upper motor neurons

In amyotrophic lateral sclerosis (ALS), onset and spread of upper motor neuron (UMN) and lower motor neuron (LMN) dysfunction is typically asymmetric. Our aim was to investigate the relationship between limb dominance and the onset and spread of clinical UMN and LMN dysfunction in ALS. We studied 138 ALS subjects with unilateral and concordant limb dominance, from two tertiary centres. A questionnaire was used to determine the pattern of disease onset and spread. The clinical severity of UMN and LMN signs in each limb was quantified using a validated scoring system. Results showed that onset of weakness was more likely to occur in the dominant upper limb (p = 0.02). In subjects with initial weakness in a non-dominant limb, spread of weakness was more likely to be to the other limb on that side (p = 0.008). The relative distribution of upper limb UMN signs was affected by whether weakness first occurred on the dominant or non-dominant side (p = 0.03). These findings support limb dominance as a significant factor underlying onset and spread of ALS, with UMN processes playing an important role. The effect of limb dominance on the presentation of ALS may reflect underlying neuronal vulnerabilities, which become exposed by the disease

Clinical and electrophysiological examination of pinch strength in patients with amyotrophic lateral sclerosis

IntroductionThe split‐hand concept has highlighted the preferential wasting of the thenar side of the hand in amyotrophic lateral sclerosis (ALS). Our objective is to re‐explore pinch grip strength to assess whether it has the potential to be a practical biomarker of ALS.MethodsWe measured different pinch grip strengths (thumb, index and fifth) using a pinch gauge from both hands of 54 ALS patients and correlated this with the Medical Research Council (MRC) score, the upper‐limb component of the revised ALS functional rating scale (ALSFRS‐R) score, and compound muscle action potentials (CMAPs) that comprise the split‐hand index.ResultsPinch grip strength using any of the three fingers showed a positive correlation with its corresponding CMAP, MRC grading and upper‐limb ALSFRS‐R score. The thumb pinch showed the strongest correlation with the split‐hand index and MRC grading.DiscussionPinch grip strength test using a simple gauge deserves further study as a potentially practical biomarker of ALS

Monocytes and neutrophils are associated with clinical features in amyotrophic lateral sclerosis

Immunity has emerged as a key player in neurodegenerative diseases such as amyotrophic lateral sclerosis, with recent studies documenting aberrant immune changes in patients and animal models. A challenging aspect of amyotrophic lateral sclerosis research is the heterogeneous nature of the disease. Here, we investigate the associations between peripheral blood myeloid cell populations and clinical features characteristic of amyotrophic lateral sclerosis. Peripheral blood leukocytes from 23 healthy controls and 48 patients with amyotrophic lateral sclerosis were analysed to measure myeloid cell alterations. The proportion of monocytes (classical, intermediates and non-classical subpopulations) and neutrophils, as well as the expression of select surface markers, were quantitated using flow cytometry. Given the heterogeneous nature of amyotrophic lateral sclerosis, multivariable linear analyses were performed to investigate associations between patients’ myeloid profile and clinical features, such as the Revised Amyotrophic Lateral Sclerosis Functional Rating Scale, Bulbar subscore of the Revised Amyotrophic Lateral Sclerosis Functional Rating Scale, change in Revised Amyotrophic Lateral Sclerosis Functional Rating Scale over disease duration and respiratory function. We demonstrate a shift in monocyte subpopulations in patients with amyotrophic lateral sclerosis, with the ratio of classical to non-classical monocytes increased compared to healthy controls. In line with this, patients with a greater disease severity, as determined by a lower Revised Amyotrophic Lateral Sclerosis Functional Rating Scale score, had reduced non-classical monocytes. Interestingly, patients with greater bulbar involvement had a reduction in the proportions of classical, intermediate and non-classical monocyte populations. We also revealed several notable associations between myeloid marker expression and clinical features in amyotrophic lateral sclerosis. CD16 expression on neutrophils was increased in patients with greater disease severity and a faster rate of disease progression, whereas HLA-DR expression on all monocyte populations was elevated in patients with greater respiratory impairment. This study demonstrates that patients with amyotrophic lateral sclerosis with distinct clinical features have differential myeloid cell signatures. Identified cell populations and markers may be candidates for targeted mechanistic studies and immunomodulation therapies in amyotrophic lateral sclerosis

Red Flags for Maltese Adults with Congenital Heart Disease: Poorer Dental Care and Less Sports Participation Compared to Other European Patients-An APPROACH-IS Substudy.

Studies in recent years have explored lifestyle habits and health-risk behaviours in adult congenital heart disease (ACHD) patients when compared to controls. The aim of this study was to investigate differences in lifestyle habits between Maltese and other European ACHD patients. Data on alcohol consumption, cigarette smoking, substance misuse, dental care and physical activity collected in 2013-2015 during "Assessment of Patterns of Patient-Reported Outcomes in Adults with Congenital Heart disease-International Study" (APPROACH-IS) were analysed. Responses from 119 Maltese participants were compared to those of 1616 participants from Belgium, France, Italy, Norway, Sweden, Switzerland and the Netherlands. Significantly fewer Maltese patients with simple (Maltese 84.1% vs. European 97.5%, p < 0.001) and moderately complex CHD (Maltese 83.6% vs. European 97.4%, p < 0.001) brushed their teeth daily. Only 67.2% of Maltese with moderately complex disease had dental reviews in the previous year compared to 80.3% of Europeans (p = 0.02). Maltese patients with simple (Maltese 31.8% vs. European 56.1%, p = 0.002) and moderately complex lesions (Maltese 30.0% vs. European 59.2%, p < 0.001) performed less regular sport activities. Comparison by country showed Maltese patients to have significantly poorer tooth brushing and sports participation than patients from any other participating country. Alcohol consumption, cigarette smoking and substance misuse were not significantly different. This study highlights lifestyle aspects that Maltese ACHD patients need to improve on, which might not be evident upon comparing patients to non-CHD controls. These findings should also caution researchers against considering behaviours among patients in one country as necessarily representative of patients on the larger scale

Whole exome sequencing and DNA methylation analysis in a clinical amyotrophic lateral sclerosis cohort

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Impaired signaling for neuromuscular synaptic maintenance is a feature of Motor Neuron Disease

A central event in the pathogenesis of motor neuron disease (MND) is the loss of neuromuscular junctions (NMJs), yet the mechanisms that lead to this event in MND remain to be fully elucidated. Maintenance of the NMJ relies upon neural agrin (n-agrin) which, when released from the nerve terminal, activates the postsynaptic Muscle Specific Kinase (MuSK) signaling complex to stabilize clusters of acetylcholine receptors. Here, we report that muscle from MND patients has an increased proportion of slow fibers and muscle fibers with smaller diameter. Muscle cells cultured from MND biopsies failed to form large clusters of acetylcholine receptors in response to either non-MND human motor axons or n-agrin. Furthermore, levels of expression of MuSK, and MuSK-complex components: LRP4, Caveolin-3, and Dok7 differed between muscle cells cultured from MND patients compared to those from non-MND controls. To our knowledge, this is the first time a fault in the n-agrin-LRP4-MuSK signaling pathway has been identified in muscle from MND patients. Our results highlight the n-agrin-LRP4-MuSK signaling pathway as a potential therapeutic target to prolong muscle function in MND