Early immune system changes in amyotrophic lateral sclerosis correlate with later disease progression.

Amyotrophic lateral sclerosis (ALS) is a fatal and incurable neurodegenerative disease with few therapeutic options. However, the immune system, including natural killer (NK) cells, is linked to ALS progression and may constitute a viable therapeutic ALS target. Tofacitinib is an FDA-approved immunomodulating small molecule which suppresses immune cell function by blocking proinflammatory cytokine signaling. This includes the cytokine IL-15 which is the primary cytokine associated with NK cell function and proliferation. However, the impact of tofacitinib on NK activation and cytotoxicity has not been thoroughly investigated, particularly in ALS. We therefore tested the ability of tofacitinib to suppress cytotoxicity and cytokine production in an NK cell line and in primary NK cells derived from control and ALS participants. We also investigated whether tofacitinib protected ALS neurons from NK cell cytotoxicity. Finally, we conducted a comprehensive pharmacokinetic study of tofacitinib in mice and tested the feasibility of administration formulated in chow. Success was assessed through the impact of tofacitinib on peripheral NK cell levels in mice. We found tofacitinib suppressed IL-15-induced activation as measured by STAT1 phosphorylation, cytotoxicity, pro-inflammatory gene expression, and pro-inflammatory cytokine secretion in both an NK cell line and primary NK cells. Furthermore, tofacitinib protected ALS neurons from NK cell-mediated cytotoxicity. In mice, we found tofacitinib bioavailability was 37% in both male and female mice; using these data we formulated mouse containing low and high doses of tofacitinib and found that the drug suppressed peripheral NK cell levels in a dose-dependent manner. These results demonstrate that tofacitinib can suppress NK cell function and may be a viable therapeutic strategy for ALS.

Muscle changes in amyotrophic lateral sclerosis: A longitudinal ultrasonography study

Amyotrophic lateral sclerosis (ALS) lacks reliable biomarkers to predict disease trajectories or guide therapeutic strategies. Sirtuin 2 (SIRT2), a NAD+-dependent deacetylase implicated in cytoskeletal destabilization and neuroinflammatory pathways in preclinical ALS models, represents a promising yet unvalidated biomarker candidate. We aimed to translate preclinical findings by validating SIRT2's role in ALS. A cross-sectional cohort study was conducted, comparing serum SIRT2 levels, measured via enzyme-linked immunosorbent assay (ELISA), between 182 ALS patients and 65 healthy controls. Clinical progression rates were derived from the ALS Functional Rating Scale-Revised (ALSFRS-R), and cognitive function was assessed using the Mini-Mental State Examination (MMSE) and Edinburgh Cognitive and Behavioral ALS Screen (ECAS). SIRT2 levels were significantly elevated in ALS patients versus controls, though diagnostic accuracy was modest (AUC = 0.620). Furthermore, SIRT2 levels showed a weak but significant positive correlation with disease progression rate (r = 0.182, p = 0.014) and inverse correlations with cognitive scores on both MMSE (r = -0.250, p = 0.032) and ECAS (r = -0.286, p = 0.031). Notably, SIRT2 demonstrated a limited but detectable ability to stratify patients into fast- and slow-progressing subgroups (AUC = 0.635). These findings provide preliminary clinical evidence linking elevated serum SIRT2 to disease progression and cognitive impairment in ALS, thereby supporting its role in disease heterogeneity. This work lends clinical support to preclinical insights, suggesting SIRT2 may aid in prognosis prediction and may represent a potential therapeutic target, necessitating further studies.

Background: Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease that is ultimately fatal but characterized by substantial phenotypic heterogeneity, which is known to impact long-term course and survival. This study investigated clinical determinants of disease progression and outcome in a large cohort of patients with ALS. Methods: Retrospective analysis included comprehensive data from 625 patients who attended a tertiary ALS centre at least twice. Patients were stratified according to five distinct clinical phenotypes: classical ALS; bulbar ALS; ALS with frontotemporal dementia (ALS-FTD); upper motor neuron predominant (UMNP); and lower motor neuron predominant (LMNP). Results: This study confirmed higher age at symptom onset, shorter latency to diagnosis and more rapid decline in the revised ALS Functional Rating Scale sum score as predictors of poor prognosis. Hazard ratios for shorter survival were higher in patients with ALS-FTD versus classical ALS, and in patients with versus without chronic obstructive pulmonary disease (COPD). Mean survival was longest in the UMNP phenotype group. Conclusions: This study confirmed established predictors of shorter survival in ALS and showed that concomitant COPD in particular relates to poor outcome.

Perivascular space (PVS) dysfunction may potentially contribute to the development and progression of amyotrophic lateral sclerosis (ALS). This study investigated the clinical relevance of PVS dysfunction in ALS. Two PVS parameters were quantified in patients with ALS: (i) the enlarged perivascular space (ePVS) score and (ii) the diffusion tensor image analysis along the perivascular space (DTI-ALPS) index. These parameters were analysed in relation to the clinical, structural and prognostic features of ALS. The study included 55 patients with ALS (33 men; mean age, 61.38 ± 10.95 years). The DTI-ALPS index was markedly reduced in the patients compared to age- and gender-matched controls, and there were no differences in ePVS scores between the two groups. The ePVS total score was positively correlated with the ALS progression, as measured by the monthly change in the revised ALS functional rating scale. The ePVS basal ganglia regional score was inversely correlated with muscle strength. Additionally, both the ePVS score and the DTI-ALPS index were associated with regional grey matter volumes of the superior frontal gyrus and middle frontal gyrus, and the DTI-ALPS index was associated with diffusion parameters of the corticostriatal and corticothalamic tracts. This study underscores the importance of PVS dysfunction in ALS according to the ePVS and a reduced DTI-ALPS index, which were respectively associated with disease progression, neurological deficits, including reduced muscle strength, and cortical and subcortical structural changes.

The monitoring of progression in amyotrophic lateral sclerosis (ALS) relies on clinical outcome measures that take months to interpret, such as revised ALS functional rating scale (ALSFRS-R) score, with no approved biomarkers. A number of clinical studies have documented the involvement of oxidative stress in ALS pathology. Pertinent to this, we propose to evaluate oxidation-reduction potential (ORP) of cerebrospinal fluid (CSF) as a potential indicator of ALS progression. The case-control study included 24 patients with neurological non-neurodegenerative disorders (controls) and 82 ALS patients with different degrees of disease (ALSFRS-R score: 21-47). ORP was significantly higher in ALS patients than controls. It was not dependent on age or gender. A strong negative correlation was found between ORP and ALSFRS-R score for all patients and patients with spinal onset. In other words, ORP increased with ALS progression. No correlation was found for the subset of patients with bulbar onset, most likely because of the physical distance between neurodegenerative loci and the site of CSF collection. These results lead to the hypothesis that ORP of CSF has a potential as monitoring biomarker in ALS, particularly in the cohort of patients with spinal onset. Antioxid. Redox Signal. 28, 1570-1575.

Metabolic abnormalities play a pivotal role in the pathogenesis of amyotrophic lateral sclerosis (ALS). Metabolic syndrome (MetS), a cluster of metabolic disorders, is highly prevalent among the elderly. However, the association between MetS and clinical characteristics, disease progression, and survival in ALS remains unclear. We included 529 ALS patients and collected demographic, clinical, and hematological data, including blood glucose, HbA1c, and lipid profiles. Patients were followed longitudinally. MetS was defined according to the criteria of the Chinese Diabetes Society. Multivariate logistic regression, Kaplan-Meier survival analysis, and Cox proportional hazards models were used to analyze. Compared to ALS patients without MetS, those with MetS had higher proportion of lower limb onset (44.3% vs. 24.6%, P < 0.001), and a faster disease progression rate (0.60 vs. 0.55, P = 0.022). After adjusting for confounders, MetS and hypertension were significantly associated with fast disease progression (OR = 1.808, 95% CI: 1.048-3.120, P = 0.033; OR = 2.615, 95% CI: 1.358-5.035, P = 0.004), and remained significant after multiple correction. Interaction analysis revealed significant interactions between glucose intolerance and dyslipidemia (P = 0.038), and between glucose intolerance and BMI (P = 0.040), but lost significance after multiple correction. There was no significant difference in survival between ALS patients with and without MetS. After adjusting for confounders, there was no significant association between MetS and the risk of death. MetS, particularly in the presence of hypertension, was associated with fast disease progression in ALS, though not with survival. These suggest metabolic dysfunction may influence ALS progression and warrant further investigation.

The Wahls diet is a modified Paleolithic diet that emphasizes dark green leafy vegetables, colorful fruits, high-quality animal proteins, and omega-3 polyunsaturated fatty acids, while limiting grains, legumes, dairy products, sugar, and processed foods containing proinflammatory omega-6 fatty acids. The Wahls diet may reduce inflammation, oxidative stress, and mitochondrial dysfunction and has plausible mechanisms for slowing amyotrophic lateral sclerosis (ALS) progression. However, research on its dietary components in the ALS animal models has yielded conflicting results. Though multiple cohort studies suggest high carotenoids, omega-3 fatty acids and fruit intake are associated with reduced ALS risks, neither the diet nor its components has been demonstrated to slow down ALS progression in case studies or clinical trials. On the contrary, the Wahls diet, a restrictive, low-carbohydrate and low glycemic index diet, caused an average weight loss of 7.2% BMI in multiple sclerosis clinical trials, which is a significant concern for people living with amyotrophic lateral sclerosis (PALS) as weight loss is associated with faster ALS progression and shorter survival. Considering the above, we cannot endorse the Wahls diet for slowing ALS progression.

Neuroinflammation is increasingly recognized as an important mediator of disease progression in patients with amyotrophic lateral sclerosis (ALS), and is characterized by reactive central nervous system (CNS) microglia and astroglia as well as infiltrating peripheral monocytes and lymphocytes. Anti-inflammatory and neuroprotective factors sustain the early phase of the disease whereas inflammation becomes proinflammatory and neurotoxic as disease progression accelerates. Initially, motor neurons sustain injuries through multiple mechanisms resulting from harmful mutations causing disruptions of critical intracellular pathways. Injured motor neurons release distress signal(s), which induce inflammatory processes produced by surrounding glial cells in the CNS as well as peripheral innate and adaptive immune cells. This review will focus on mechanisms of neuroinflammation and their essential contributions in ALS pathogenesis. Regulatory T lymphocytes (Tregs) are a subpopulation of immunosuppressive T lymphocytes that become reduced and dysfunctional as the disease progresses in ALS patients. Their degree of dysfunction correlates with the extent and rapidity of the disease. Treg numbers are boosted in transgenic mutant SOD1 (mSOD1) mice through the passive transfer of Tregs or through treatment with an interleukin-2/ interleukin-2 monoclonal antibody complex and rapamycin. Treating the transgenic mice with either of these modalities delays disease progression and prolongs survival. In addition, Treg function is restored when dysfunctional Tregs are isolated from ALS patients and expanded ex vivo in the presence of interleukin-2 and rapamycin. Based on these findings, a first-in-human phase 1 trial has been completed in which expanded autologous Tregs were infused back into ALS patients as a potential treatment. The infusions were safe and shown to 'hit target' by enhancing both Treg numbers and suppressive functions. A delicate balance between anti-inflammatory and proinflammatory factors modulates the rates of disease progression and survival times in ALS. Tipping the balance toward the anti-inflammatory mediators shows promise in slowing the progression of this devastating disease.

Amyotrophic lateral sclerosis (ALS) is a deadly neurodegenerative disease where the immune system contributes to progression, though the underlying immune mechanisms are unclear. Natural killer (NK) cells likely play a critical role in disease progression: they are responsible for dispatching damaged cells, and during ALS they accumulate in the CNS and increase the rate of neuronal death. Thus, we hypothesize that NK cells are more cytotoxic in ALS patients than in healthy controls. To test this, primary NK cells were isolated from the blood of control and ALS patients and co-cultured for four hours at a 1:1 ratio with K-562 cancer cells. K-562 cell death was measured via e500 viability dye staining and used to quantify NK cell cytotoxicity. Surprisingly, we found that NK cell cytotoxicity was significantly reduced in ALS NK cells compared to healthy controls. Next, using flow cytometry, we measured a battery of peripheral inflammatory markers and correlated these measures with NK cell cytotoxicity to identify immune pathways impacting NK cell cytotoxicity. Unsurprisingly, in healthy control patients there was significant correlation between NK cell markers and NK cell cytotoxicity. However, these correlations were absent in ALS patients. Together, these data suggest that NK cell cytotoxicity is downregulated in ALS, likely as a mechanism to slow NK cell-mediated damage to motor neurons, though further studies will be required to elucidate the underlying mechanisms.

Amyotrophic lateral sclerosis (ALS) is a rare, devastating neurodegenerative disease that affects upper and lower motor neurons, resulting in muscle atrophy, spasticity, hyperreflexia, and paralysis. Inflammation plays an important role in the development of ALS, and associated with rapid disease progression. Current observational studies indicate the thinning of cortical thickness in patients with ALS is associated with rapid disease progression and cognitive changes. However, the effects of inflammatory cytokines on cortical thickness in patients with ALS are unclear. Here, we investigated the relationship between inflammatory cytokines and cortical thickness in patients with ALS. We evaluated 51 patients with ALS for inflammatory cytokines including interleukin (IL)-4, interferon (IFN)-α, IL-1β, IL-2, IL-5, IL-12, tumor necrosis factor (TNF)-α, IL-6, IL-10, IL-8, IL-17, and IFN-γ and analyzed the correlation between these indicators and the ALS functional rating scale-revised (ALSFRS-R) score or disease progression rate (ΔFS score). Twenty-six patients with ALS and 26 controls were studied using whole-cortex analysis, and post-hoc analyses were performed to examine the correlation between brain cortical thickness and ALSFRS-R or ΔFS scores. IL-4, IFN-α, IL-1β, and IL-2 levels were significantly correlated with ALSFRS-R scores, and the IL-2 level was significantly correlated with ΔFS scores. After controlling for age and sex, the ALS group had thinner cortexes in multiple clusters across the brain than the control group. Further analyses revealed that cortical thickness in the right superior temporal and lingual gyrus regions was inversely correlated with ΔFS scores. There was a significant positive correlation between the clusters in the right lingual cortex and IL-2 level. These results suggest cortical thickness was reduced in patients with ALS in motor and non-motor cortical areas. Inflammatory factors (especially IL-2) were correlated with cortical thickness, and both were related to the disease progression rate, suggesting IL-2 plays an important role in ALS.

Safety and efficacy of lithium in combination with riluzole for treatment of amyotrophic lateral sclerosis: a randomised, double-blind, placebo-controlled trial

Background: There are no reliable biomarkers that could evaluate the disease burden in amyotrophic lateral sclerosis (ALS). Objectives: The aim of our study is to evaluate the changes in cerebrospinal fluid (CSF) and serum neurofilament subunit L (NF-L) in patients with ALS and to analyze the correlations between the levels of NF-L and clinical parameters. Method: CSF and serum samples were obtained from 80 ALS patients and 40 controls. The levels of NF-L in CSF and serum were assessed, and disease progression parameters including duration, revised ALS Functional Rating Scale (ALSFRS-r) score, disease progression rate (DPR), upper motor neuron (UMN) score, and survival were analyzed by registered neurologists. All samples were measured using a commercial enzyme-linked immunosorbent assay. Statistical analyses were performed using Prism software. Results: Compared to the controls, the ALS patients displayed significantly increased levels of NF-L; these values were negatively correlated with the ALSFRS-r score and positively correlated with the decrease in ALSFRS-r score, DPR, and UMN score. There was no correlation between levels of NF-L and duration. In addition, the cumulative survival rate in ALS patients with a low level of NF-L was higher than in patients with a high level of NF-L. Conclusions: NF-L levels increased in CSF and serum of patients with ALS. NF-L may thus be a neurodegenerative biomarker for predicting ALS severity and progression, and the survival of patients with this disease.

ObjectiveElectrical impedance myography (EIM) is a promising biomarker for amyotrophic lateral sclerosis (ALS). A key issue is how best to utilise the complex high dimensional, multi-frequency data output by EIM to fully characterise the progression of disease. MethodsMuscle volume conduction properties were obtained from EIM recordings of the tongue across three electrode configurations and 14 input frequencies (76 Hz–625 kHz). Analyses of individual frequencies, averaged EIM spectra and non-negative tensor factorisation were undertaken. Longitudinal data were collected from 28 patients and 17 healthy volunteers at 3-monthly intervals for a maximum of 9 months. EIM was evaluated against the Amyotrophic Lateral Sclerosis Functional Rating Scale-Revised (ALSFRS-R) bulbar sub-score, tongue strength and an overall bulbar disease burden score. ResultsLongitudinal changes to individual patient EIM spectra demonstrated complex shifts in the spectral shape. At a group level, a clear pattern emerged over time, characterised by an increase in centre frequency and general shift to the right of the spectral shape. Tensor factorisation reduced the spectral data from a total of 168 data points per participant per recording to a single value which captured the complexity of the longitudinal data and which we call tensor EIM (T-EIM). The absolute change in tensor EIM significantly increased within 3 months and continued to do so over the 9-month study duration. In a hypothetical clinical trial scenario tensor EIM required fewer participants (n = 64 at 50% treatment effect), than single frequency measures (n range 87–802) or ALSFRS-R bulbar subscore (n = 298). ConclusionsChanges to tongue EIM spectra over time in ALS are complex. Tensor EIM captured and quantified disease progression and was more sensitive to changes than single frequency EIM measures and other biomarkers of bulbar disease. SignificanceObjective biomarkers for the assessment of bulbar disease in ALS are lacking. Tensor EIM enhances the biomarker potential of EIM data and can improve bulbar symptom monitoring in clinical trials.

Background and ObjectiveIn amyotrophic lateral sclerosis (ALS), progressive weakness significantly limits the ability to exercise. However, measurements of the impaired exercise function and their practical value to assess disease progression in ALS are scarce. Cardiopulmonary exercise testing (CPET) is a non-invasive accurate method used to comprehensively quantify exercise physiology in a variety of diseases. This study aimed to evaluate the clinical value of CPET and to explore its association with disease severity and prognosis prediction in ALS.MethodsA total of 319 participants were enrolled in this 3-year prospective study. After strict quality control, 109 patients with ALS and 150 age- and sex-matched healthy controls were included with comprehensive clinical assessment and follow-ups. The incremental ramp protocol for symptom-limited CPET was applied in both groups. The exercise physiology during peak effort exercise was systematically measured, including the overall aerobic capacity of exercise (VO2 peak) and the respective capacity of the exercise-involved organs [cardiac response (heart rate peak—HR peak), ventilatory efficiency (VE/VCO2 slope), breathing economy (VE/VO2 peak), and other relevant parameters]. Disease severity and progression were evaluated using recognized scales. Survival was monitored with regular follow-ups every 6 months.ResultsDecreased exercise capacity (VO2 peak < 16 ml/kg/min) occurred more frequently in patients with ALS than in controls (44.95% vs. 9.33%, p < 0.01). In patients with ALS, the average VO2 peak (16.16 ± 5.43 ml/kg/min) and HR peak [135 (112–153) bpm] were significantly lower (p < 0.01) than in controls [22.26 ± 7.09 ml/kg/min; 148 (135–164) bpm], but the VE/VCO2 slope was significantly higher [28.05 (25.03–32.16) vs. 26.72 (24.37–29.58); p = 0.03]. In patients with ALS, the VO2 peak and HR peak were significantly correlated with disease severity and progression scores (p < 0.05). Survival analyses revealed the VO2 peak and HR peak as protective indicators while the VE/VO2 peak as a detrimental indicator for the prognostic prediction in ALS (HR = 0.839, p = 0.001; HR = 0.967, p < 0.001; HR = 1.137, p = 0.028, respectively).ConclusionOur prospective study quantified the significantly decreased exercise capacity in ALS through non-invasive CPET. The impaired VO2 peak and HR peak closely correlated with disease severity and independently predicted a worse prognosis. Our findings identified the clinical value of CPET as an objective indicator of disease progression in ALS.