Produced by the mitochondria and endoplasmic reticulum, neurosteroids such as allopregnanolone are neuroprotective molecules that influence various neuronal functions and regulate neuroinflammation. They are reduced in neurodegenerative diseases, while in the Wobbler mouse model, allopregnanolone and its precursor progesterone showed protective effects on motor neuron degeneration. This single-center case-control study included 37 patients with amyotrophic lateral sclerosis (ALS) and 28 healthy controls. Cerebrospinal fluid (CSF) neurosteroid levels were quantified using liquid chromatography–electrospray tandem mass spectrometry and compared between the two cohorts. Neurosteroid concentrations have been correlated with neuroinflammation and neurodegeneration biomarkers detected through an automated immunoassay, along with disease features and progression. Pregnenolone, progesterone, allopregnanolone, pregnanolone, and testosterone levels were significantly lower in ALS patients’ CSF compared to healthy controls. A significant inverse correlation was found between neurofilament and neurosteroid levels. Neurosteroid concentrations did not correlate with disease progression, phenotype, genotype, or survival prediction. Our study suggests the independence of the disease features and its progression, from the dysregulation of neurosteroids in ALS patients’ CSF. This neurosteroid reduction may relate to disease pathogenesis or be a consequence of disease-related processes, warranting further research. The inverse correlation between neurosteroids and neurofilament levels may indicate a failure of compensatory neuroprotective mechanisms against neurodegeneration.

Mitochondrial dysfunction is a key pathological hallmark in amyotrophic lateral sclerosis (ALS), yet the role of circulating cell-free mitochondrial DNA (Cf-mtDNA) as a biomarker remains unclear. This study aimed to investigate serum Cf-mtDNA levels in ALS patients compared to healthy controls and explore its associations with disease biomarkers, clinical progression, and survival. We conducted a case–control study measuring Cf-mtDNA levels in serum samples from 54 ALS patients and 36 age- and sex-matched healthy controls using quantitative droplet digital PCR. Correlations between Cf-mtDNA levels and clinical features, neurofilament concentrations, inflammatory indices, and survival were assessed. The average Cf-mtDNA level in ALS patients was 2,426,315 copies/mL of serum (IQR: 865000–2475000), compared to 1,885,667 copies/mL of serum (IQR: 394250–2492500) in controls (p = 0.308). ROC analysis yielded an AUC of 0.595 (95% CI: 0.468–0.721), indicating very limited discriminant ability. Cf-mtDNA levels were inversely correlated with serum creatinine concentrations (r = –0.335, p = 0.018), but showed no significant associations with ALS phenotype, disease staging, neurofilaments, inflammatory indices, or survival. These findings suggest that, in a predominantly sporadic ALS cohort, serum Cf-mtDNA may not serve as a standalone diagnostic or prognostic biomarker, in contrast to previous reports. Methodological differences, cohort composition, and genetic heterogeneity may account for these discrepancies. Our results underscore the importance of further large-scale, longitudinal studies incorporating genetic stratification and multi-biomarker approaches to better elucidate the role of Cf-mtDNA in ALS pathophysiology.

ALS is characterized by a highly heterogeneous course, ranging from slow and uncomplicated to rapid progression with severe extra-motor manifestations. This study investigated ALS-related hospitalizations and their connection to clinical aspects, comorbidities, and prognosis. We performed a retrospective cohort study including patients residing in Modena, Italy, newly diagnosed between 2007 and 2017 and followed up until 31 December 2022. Data were obtained from the Emilia Romagna ALS registry, regional hospitals, and medical records. Among the 249 patients, there were 492 hospital admissions, excluding those for diagnostic purposes; 63% of the patients had at least one hospitalization post-diagnosis, with an average stay of 19.90 ± 23.68 days. Younger patients were more likely to be hospitalized multiple times and experienced longer stays (44.23 ± 51.71 days if <65 years; 26.46 ± 36.02 days if older, p < 0.001). Patients who were hospitalized at least once more frequently underwent gastrostomy (64.97%) or non-invasive (66.24%) and invasive (46.50%) ventilation compared to those never hospitalized (21.74%, 31.52%, 13.04%, respectively, p < 0.001 for all). Emergency procedures led to longer hospitalizations (62.84 ± 48.91 days for non-invasive ventilation in emergencies vs. 39.88 ± 46.46 days electively, p = 0.012). Tracheostomy-free survival was not affected by hospitalizations. In conclusion, younger ALS patients undergo frequent and prolonged hospitalizations, especially after emergency interventions, although these do not correlate with reduced survival.

Type 2 diabetes mellitus (T2DM) as a comorbidity in amyotrophic lateral sclerosis (ALS) has sparked interest for its potential impact on disease expression and prognosis. In this retrospective cohort study, we investigated the prevalence and clinical correlates of T2DM in a large cohort of patients from the ALS registry of a Northern Italy region, Emilia Romagna, established in 2009. Out of 1756 ALS patients enrolled up to 2021, 145 were affected by T2DM (diALS). Patients with diALS were older than those without T2DM (ndALS) (71.56 vs. 65.76 years, p < 0.001), had a higher body mass index (25.63 vs. 24.23, p < 0.001), but experienced greater weight loss at diagnosis (6.87% vs. 5.44%, p < 0.007). Respiratory onset (6.2% vs. 2.6%, p = 0.013) and respiratory phenotype (4.2% vs. 1.4%, p = 0.04) were more frequent among diALS. Coherently, diALS presented a lower forced vital capacity (74.9% vs. 87.9%, p ≤ 0.001) and more frequently adopted Non-Invasive Ventilation (NIV) (50.35% vs. 37.61%, p = 0.003), with significant influence on time to NIV (HR 1.71, 95% CI 1.07–2.74, p = 0.024). Exploring genetic background, among all the genes examined C9ORF72 emerged as underrepresented among diALS (7.64% in ndALS vs. 0% in diALS, p = 0.039). In conclusion, we confirmed a more severe respiratory dysfunction in diALS, suggesting a specific frailty in respiratory muscles, together with some peculiar clinical features consistent with the previous literature data, such as a later onset. The lower prevalence of C9ORF72 expansion in this population may hint towards a specific role of the gene in metabolism and inflammation, granting more space to non-genetic causes, warranting further studies for confirmation.