STAC3 binding to CaV1.1 II-III loop is nonessential but critically supports skeletal muscle excitation-contraction coupling.

Skeletal muscle excitation-contraction (EC) coupling depends on the direct coupling between CaV1.1 on the sarcolemma and ryanodine receptor (RyR1) on the sarcoplasmic reticulum. A key regulator of this process is STAC3, a protein essential for both the functional expression of CaV1.

Nusinersen corrects L-arginine deficiency in the cerebrospinal fluid of patients with severe spinal muscular atrophy.

Spinal Muscular Atrophy (SMA) is a progressive neuromuscular disorder caused by homozygous loss of the survival motor neuron 1 (SMN1) gene, leading to reduced SMN protein expression. Increasing evidence implicates neurotransmission deficits in the pathophysiology of SMA. In particular, alterations in neuroactive amino acids involved in glutamatergic neurotransmission have recently been identified in both the cerebrospinal fluid (CSF) of SMApatients and the spinal cord of SMNΔ7 mouse models.

Missense variants in cause myo-tubulinopathies.

Tubulinopathies encompass a wide spectrum of disorders resulting from variants in genes encoding α- and β-tubulins, the key components of microtubules. While previous studies have linked or dominantly inherited missense variants to neurodegenerative phenotypes, including amyotrophic lateral sclerosis, frontotemporal dementia, hereditary spastic ataxia, and more recently, an isolated report of congenital myopathy, the full phenotypic and genotypic spectrum of -related disorders remains incompletely characterised. In this multi-centre study, we identified 13 novel missense variants in 31 individuals from 19 unrelated families.

Spinal Muscular Atrophy Functional Composite Score Revised (SMA-FCR) in Untreated and Nusinersen-Treated Patient Cohorts.

Background And Objectives: The Spinal Muscular Atrophy Functional Composite (SMA-FC) combines scores from the Hammersmith Functional Motor Scale Expanded (HFMSE), Upper Limb Module (ULM), and Six-Minute Walk Test (6MWT) into a single score and removes the floor and ceiling effects of the HFMSE. Our objective was to evaluate a revised version of the SMA-FC (SMA-FCR) by including the Revised ULM (RULM) in untreated and nusinersen-treated SMA.

Methods: We included participants with HFMSE, RULM, and 6MWT data at the same visit.

Longitudinal Assessment of 4-Year HFMSE Changes in SMA II and III Patients Treated With Nusinersen.

Background: The aim of this international retrospective study was to assess 4-year change using the Hammersmith Functional Motor Scale Expanded (HFMSE) in individuals with type II and III spinal muscular atrophy (SMA) treated with nusinersen and to establish predictors of HFMSE changes.

Methods: Individuals with type II or III SMA, and at least 4 years of nusinersen-only treatment were included. All were assessed using the HFMSE.

Genotype variability in early-onset Hereditary Spastic Paraplegia: a single-center study.

Hereditary spastic paraplegias (HSPs) are genetically and clinically heterogeneous, slowly progressive neurological disorders characterized by primary involvement of the corticospinal tracts. The early-onset forms of HSP (EO-HSP) are often defined as "cerebral palsy mimics" since symptoms begin in infancy and manifest as spastic di- or tetraplegia and possible neurodevelopmental disorder. The rarity and heterogeneity of these disorders make their diagnosis challenging.

Clinical validity of congenital myopathy genes determined by the ClinGen Congenital Myopathies Expert Panel.

Background: Congenital myopathies are a group of neuromuscular disorders that typically present at birth or early childhood with hypotonia and non-progressive or slowly progressive muscle weakness. They are classically subclassified by characteristic structural changes and histopathological findings in skeletal muscle. Variants in over 40 genes have been described to date in patients with various forms of congenital myopathy with overlapping phenotypic and histological features, which poses a challenge for laboratories and clinicians in interpreting genetic findings.

Italian validation of the SMA independence scale-upper limb module.

Spinal muscular atrophy (SMA) is a progressive disorder caused by SMN1 mutations. While therapies have changed its course, current motor scales often miss aspects. This study aimed to validate the Italian SMA Independence Scale (SMAIS-ULM) for reliability, applicability, and expansion across diverse SMA phenotypes.

Opinion of the Italian Association of Myology on Ataluren for the Treatment of Nonsense Mutation Duchenne Muscular Dystrophy.

The Italian Duchenne muscular dystrophy expert clinicians, gathered in the Italian Association of Myology (AIM), intend to express a position against the suspension of the Marketing Authorization of ataluren (Translarna) for the treatment of nonsense mutation Duchenne muscular dystrophy. The marketing authorization has been recently withdrawn by the European Commission following a recommendation from the Committee for Medicinal Products for Human Use of the European Medicines Agency. This negative recommendation was based on the fact that three randomized controlled trials of ataluren in nonsense mutation Duchenne muscular dystrophy (007, 020, and 041) have failed to show statistically significant differencs in favor of the treatment in the selected primary outcomes for each individual study, i.

Myostatin Levels in SMA Following Disease-Modifying Treatments: A Multi-Center Study.

Objective: This study investigated myostatin levels in SMA patients receiving disease-modifying therapies (DMTs) to understand their relationship with treatment duration and functional status.

Methods: Our study includes both cross-sectional and longitudinal analyses of myostatin levels in treated SMA patients. The longitudinal cohort included 46 treatment-naive patients assessed at baseline and 12 months post-treatment.

Patients on treatment with risdiplam in Italy: challenges in the interpretation of the real-world data.

Aims: (i) provide a snapshot from a large cohort of Italian patients with SMA on risdiplam in the real-world setting; (ii) identify any differences in the cohorts before and after commercial drug approval considering the different eligibility access criteria (iii) describe preliminary data on adherence to treatment and reasons for shifting from nusinersen to risdiplam.

Methods: Charts from patients on risdiplam were retrospectively reviewed. Results were then compared between patients accessing the drug during an initial restricted compassionate use program (cohort 1) and those after commercial approval, with no restrictions (cohort 2).

Dysregulated balance of D- and L-amino acids modulating glutamatergic neurotransmission in severe spinal muscular atrophy.

Spinal muscular atrophy (SMA) is a neuromuscular disorder caused by reduced expression of the survival motor neuron (SMN) protein. In addition to motor neuron survival, SMN deficiency affects the integrity and function of afferent synapses that provide glutamatergic excitatory drive essential for motor neuron firing and muscle contraction. However, it is unknown whether deficits in the metabolism of excitatory amino acids and their precursors contribute to neuronal dysfunction in SMA.

Three Cases of Spinocerebellar Ataxia Type 2 (SCA2) and Pediatric Literature Review: Do Not Forget Trinucleotide Repeat Disorders in Childhood-Onset Progressive Ataxia.

: Childhood-onset progressive ataxias are rare neurodegenerative disorders characterized by cerebellar signs, sometimes associated with other neurological or extra-neurological features. The autosomal dominant forms, known as spinocerebellar ataxias (SCAs), linked to trinucleotide (i.e.

Congenital Ataxia with Progressive Cerebellar Atrophy, Camptodactyly, and Hypertrichosis: A Novel Recognizable Phenotype for NALCN Heterozygous Variants.

Background: Non-selective sodium leak channel (NALCN) protein encoded by the gene is of key importance for neuronal cell excitability. Previous reports showed that biallelic pathogenic variants cause infantile hypotonia with psychomotor retardation and characteristic facies 1 (IHPRF1) while monoallelic variants lead to congenital contractures of the limbs and face, hypotonia, and developmental delay (CLIFAHDD). In our work, we aimed to expand the heterozygous -related clinical spectrum, presenting two affected individuals and a literature review.

Type I spinal muscular atrophy and disease modifying treatments: a nationwide study in children born since 2016.

Background: The advent of disease-modifying treatments (DMT) has changed natural history in 5q Spinal muscular atrophy (SMA). The aim of this study was to report survival and functional aspects in all the Italian type I children born since 2016.

Methods: The study included all symptomatic children with type I SMA born since January 1st, 2016, when DMTs became available in Italy.

Dysregulated balance of D- and L-amino acids modulating glutamatergic neurotransmission in severe spinal muscular atrophy.

Spinal muscular atrophy (SMA) is a neuromuscular disorder caused by reduced expression of the survival motor neuron (SMN) protein. In addition to motor neuron survival, SMN deficiency affects the integrity and function of afferent synapses that provide glutamatergic excitatory drive essential for motor neuron firing and muscle contraction. However, it is unknown whether deficits in the metabolism of excitatory amino acids and their precursors contribute to neuronal dysfunction in SMA.

Association between Reported Sleep Disorders and Behavioral Issues in Children with Myotonic Dystrophy Type 1-Results from a Retrospective Analysis in Italy.

Sleep disorders have been poorly described in congenital (CDM) and childhood (ChDM) myotonic dystrophy despite being highly burdensome. The aims of this study were to explore sleep disorders in a cohort of Italian CDM and ChDM and to assess their association with motor and respiratory function and disease-specific cognitive and behavioral assessments. This was an observational multicenter study.

De Novo GRID2 Variant as a Cause of Ataxia with Oculomotor Apraxia and Alpha-Fetoprotein Elevation.

Bi-allelic pathogenic variants in GRID2 have been initially associated to an autosomal recessive form of spinocerebellar ataxia, namely SCAR18. Subsequently, few monoallelic cases have been described. Here we present a new subject harboring a novel de novo heterozygous GRID2 missense variant presenting with progressive ataxia together with cerebellar atrophy and, for the first time, alpha-fetoprotein (AFP) elevation.

Upper limb function changes over 12 months in untreated SMA II and III individuals: an item-level analysis using the Revised Upper Limb Module.

The Revised upper limb module (RULM) has been increasingly used in clinical trials and in clinical settings. The aim of this study was to use the 'shift analysis' to assess the patterns of lost or gained abilities for each item on the RULM in an untreated cohort, stratified by SMA type, age, SMN2 copy number, and motor functional status. The analysis was performed on 222 12-month paired assessments from 129 individuals (115 assessment from type II and 107 from type III) who had at least two assessments at yearly intervals.

Proteomics profiling and machine learning in nusinersen-treated patients with spinal muscular atrophy.

Aim: The availability of disease-modifying therapies and newborn screening programs for spinal muscular atrophy (SMA) has generated an urgent need for reliable prognostic biomarkers to classify patients according to disease severity. We aim to identify cerebrospinal fluid (CSF) prognostic protein biomarkers in CSF samples of SMA patients collected at baseline (T0), and to describe proteomic profile changes and biological pathways influenced by nusinersen before the sixth nusinersen infusion (T302).

Methods: In this multicenter retrospective longitudinal study, we employed an untargeted liquid chromatography mass spectrometry (LC-MS)-based proteomic approach on CSF samples collected from 61 SMA patients treated with nusinersen (SMA1 n=19, SMA2 n=19, SMA3 n=23) at T0 at T302.

Parental diagnostic delay and developmental outcomes in congenital and childhood-onset myotonic dystrophy type 1.

Aim: To investigate the timing of type 1 myotonic dystrophy (DM1) diagnosis in parents of affected children and describe children's perinatal characteristics and developmental outcomes.

Method: This was a descriptive case series of children with congenital myotonic dystrophy (CDM) and childhood-onset myotonic dystrophy (ChDM). Parental timing of DM1 diagnosis and the perinatal, motor, and cognitive outcomes of paediatric patients were recorded.