Serum C-Reactive Protein as a Prognostic Biomarker in Amyotrophic Lateral Sclerosis

Proximity extension assay reveals serum inflammatory biomarkers in two amyotrophic lateral sclerosis cohorts

Amyotrophic lateral sclerosis (ALS) is a rare neurodegenerative disease with both clinical and hereditary heterogeneity. Inflammation has been suggested to play an important role in ALS pathophysiology. In this study, we aimed to identify serum inflammatory alterations and develop effective inflammatory biomarkers to assist in the diagnosis of ALS. Through proximity extension assay (PEA), we investigated serum inflammatory alterations in two ALS cohorts compared with healthy controls (HCs), including sporadic ALS patients and genetic ALS patients. We found that CHIT1, OSM, SIRT2, CDCP1 and 5 other factors were significantly increased in sporadic ALS patients in both cohorts and that SIRT2, CDCP1 and 6 other factors were different between genetic ALS patients and HCs. Using XGBoost and binary logistic regression analysis, we developed a two-serum protein diagnostic panel (CHIT1 and CDCP1), and the area under the curve (AUC) was 0.904 in the original cohort and 0.907 in the replication cohort. Based on Mendelian Randomization (MR), OSM and SIRT2 are significantly associated with the risk of ALS. In conclusion, our study revealed a consistent and replicable serum inflammatory profile and developed a biomarker panel that can differentiate ALS patients from HCs in two cohorts, which may play an important role in advancing our current understanding of the inflammatory process and identifying novel therapeutic strategies for ALS patients.

Routine blood biochemical biomarkers in amyotrophic lateral sclerosis: Systematic review and cohort analysis

Introduction: Blood biochemical biomarkers, including urate, creatinine, albumin, and creatine kinase, have been shown to be useful in ALS. To provide further information about the roles of these four biomarkers roles we performed a systematic review. In addition, we also performed a new study of the role of these biomarkers in predicting survival, using data from our local ALS cohort. Methods: (1) Using established databases and other sources, we searched for papers about the use of urate, creatinine, albumin, and creatine kinase as biomarkers in ALS. Included articles were reviewed for information about biomarker levels in ALS and controls, association with markers of functional decline, and survival. (2) For our local ALS cohort, we performed survival analysis, Cox-proportionate-hazard ratio and ROC curves to investigate the use of these biomarkers in predicting survival. Results: (1) For systematic review, 104 papers were included. There was some variability in the findings. For urate, there was evidence of decreased levels in ALS, with higher levels associated ith longer survival. For creatinine, there was evidence of decreased levels in ALS, and higher levels correlated with longer survival. For albumin, some reports of reduced levels in ALS, but no consistent association with survival. For creatine kinase, some reports of increased levels in ALS, with inconsistent association with survival. (2) For the local ALS cohort there was evidence that urate and creatinine were associated with survival, but no significant association with survival. There was less evidence for albumin and CK. Discussion: This study provides support for further studies of these readily available biochemical measurement as bioamerkers in ALS.

Elevated Serum MCP-2 and TARC Associated With Increased Risk of Death in Guamanian ALS Patients

BACKGROUND

This study explores the relationship between inflammation and longevity in a high-incidence focus of amyotrophic lateral sclerosis (ALS) in post-WWII Guam. Characteristics of this focus include the sudden appearance of the disease in high numbers and the unusually long lifespan (without medical interventions) seen in some cases. We used bio-banked specimens to evaluate the relationship between serum immunoregulators and survival time.

METHODS

We evaluated sera from 69 Guam ALS cases collected within 2 years of symptom onset by NIH researchers from 1950 to 1983 for 11 immunoregulators via ELISA (CRP, eotaxin-1, RANTES, IL-6, IL-8, IL-10, IFN-γ, IP-10, MCP-1, MCP-2 and TARC). Factor analysis identified two factors responsible for ~68% of the variation in the data. We estimated Cox proportional hazards models to identify immunoregulators associated with time to death.

RESULTS

Each 10-unit increase in factor 2 cytokines (MCP-2 and TARC) was associated with a 38% increase in the risk of death (HR: 1.38; 95% CI: 1.19, 1.65; p: 0.00).

DISCUSSION

Like sporadic ALS cases worldwide, inflammation is associated with a shortened lifespan in Guamanian ALS; more specifically, our findings suggest serum levels of MCP-2 and TARC at onset may predict disease duration. Further investigation is needed to determine the role of these immunoregulators in disease prognosis and as targets for diagnostic and therapeutic interventions.

Cortical thickness correlated with peripheral inflammatory cytokines in amyotrophic lateral sclerosis

Introduction

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.

Methods

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.

Results

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.

Conclusion

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.

Changes in immuno-inflammatory and antioxidant biomarkers in serum and cerebrospinal fluid of dogs with distemper

Canine distemper virus (CDV) causes a multisystemic disease with central nervous system involvement in dogs. Little is known about the role of immuno-inflammatory and redox-state biomarkers in the pathogenesis and diagnosis of naturally occurring CDV infection. Thus, the objectives of this study were: 1) to evaluate the potential differences in a profile of cytokines/chemokines, and inflammatory and redox-status biomarkers in serum between dogs with CDV-infection and healthy dogs, and 2) possible correlations between serum/blood and cerebrospinal fluid (CSF) of these biomarkers in dogs with CDV-infection. Two groups of dogs were designed: 10 with CDV-infection, and 10 healthy. A total of 13 cytokines/chemokines, 3 inflammatory (C-reactive protein [CRP], haptoglobin [Hp], and butyrylcholinesterase [BChE]) and 3 antioxidants of redox status (cupric reducing antioxidant capacity [CUPRAC], Thiol, and ferric reducing ability of plasma [FRAP]) were analyzed in serum and CSF samples. Serum IL-7, IL-8, MCP-1, CRP, Hp, FRAP and Thiol levels were higher (P < 0.05) in dogs with CDV compared to controls. There were significant (P < 0.05) correlations only in IL-6 and MCP-1 between CSF and serum. In conclusion, deregulated immune response, raised inflammation, and imbalances of redox homeostasis and antioxidant defense status may play role in the pathophysiological mechanism of neurological form of CDV-infection. The combination of clinical features and cytokine biomarkers (IL-7, IL-8 and MCP-1) might facilitate clinical diagnosis for neural involvement in dogs with CDV. Some cytokine/chemokine (IL-6 and MCP-1) in CSF are highly correlated with those of serum, indicating that serum samples could reflect the possible changes of these analytes in CSF.

Prognostic Value of Systemic Inflammation, Nutritional Status and Sarcopenia in Patients With Amyotrophic Lateral Sclerosis

BACKGROUND

Nutritional status, systemic inflammatory responses and muscle mass are associated with the prognosis of patients with amyotrophic lateral sclerosis (ALS). However, the optimal biomarker for predicting prognosis remains unclear. This study aimed to identify the optimal indicators of survival among the nutrition-based, inflammation-based and muscle mass-related markers for ALS patients.

METHODS

We enrolled ALS patients from January 2014 to December 2019. Experienced neurologists followed up with the participants until January 2022. This study included a total of 17 nutritional, systemic inflammatory or muscle mass-related indicators. Maximally selected rank statistics determined the cut-off points for these indicators. Kaplan-Meier estimation was used to assess survival. Uni- and multivariate Cox proportional hazards models were used to determine the effects of indicators on survival. Finally, time-dependent receiver operating characteristic (time-ROC) curves and the C-index were calculated to evaluate the predictive efficacy of different indicators.

RESULTS

A total of 506 patients with ALS were enrolled in this study, including 288 males (56.9%) and 218 females (43.1%), with a mean age of 54.2 ± 10.5 years. Among these ALS patients, 334 cases (68.0%) either died or underwent tracheotomy. In univariate Cox proportional hazards regression, 11 indicators were significantly associated with ALS survival (p < 0.05). And systemic immune inflammation (SII), platelet-to-lymphocyte ratio (PLR), modified geriatric nutritional risk index (mGNRI), creatinine and sarcopenia index (SI, (creatinine/cystatin C) × 100) were determined as independent predictors (p < 0.05) in multivariate Cox proportional hazards regression. A higher SI predicted longer survival (hazard ratio, 0.59; 95% confidence interval [CI], 0.46-0.76; p < 0.001). The results of time-ROC and C-index analyses indicated that SI had the best predictive efficacy for ALS survival, with a C-index of 0.65 (95% CI, 0.54-0.75) for 1-year, 0.61 (95% CI, 0.57-0.65) for 3-year and 0.59 (95% CI, 0.55-0.62) for 5-year survival. Across different subgroups, SI had the highest C-index in men and women, limb onset and aged < 60 year ALS patients, compared with other indicators. However, cystatin C was the best indicator for predicting the survival of ALS patients with bulbar onset, whereas the prognostic nutritional index (PNI) was the best for those aged ≥60 years.

CONCLUSIONS

The serum SI demonstrates superior prognostic ability compared to other inflammation-based, nutrition-based and muscle mass-related indicators for patients with ALS. Given its simplicity and availability, it is well suited for clinical use in evaluating the prognosis of ALS patients.

Lower creatinine-to-cystatin c ratio associated with increased risk of incident amyotrophic lateral sclerosis in the prospective UK biobank cohort

Reduced muscle mass has been associated with the progression and prognosis of amyotrophic lateral sclerosis (ALS). However, it remains unclear whether decreased muscle mass is a risk factor for ALS or a consequence of motor neuron degeneration. Recently, serum creatinine-to-cystatin C ratio (CCR) have emerged as promising biomarkers for assessing muscle mass. We aimed to explore the association between CCR and the incidence of ALS using data from the UK Biobank. Between 2006 and 2010, 446,945 participants were included in the baseline. CCR was calculated as the ratio of serum creatinine to cystatin C. Cox regression models were used to analyze the relationship between CCR and ALS incidence. Furthermore, subgroup analyses were conducted to investigate potential covariates in these relationships. After adjusting for all covariates, the multivariate Cox regression analysis revealed a significant association between decreased CCR and an increased risk of ALS (hazard ratio (HR) = 0.990, 95% confidence interval (CI): 0.982-0.999, P = 0.026). Participants were stratified into groups based on CCR tertiles. Compared with participants in the highest tertiles of CCR, those in the lowest (HR = 1.388, 95% CI: 1.032-1.866, P = 0.030) and medium tertiles (HR = 1.348, 95% CI: 1.045-1.739, P = 0.021) had an increased risk of ALS incidence. Subgroup analysis showed that the relationship between CCR and ALS incidence was particularly significant among participants aged < 65 years (CCR tertile 1: HR = 1.916, 95% CI: 1.366-2.688, P < 0.001; CCR tertile 2: HR = 1.699, 95% CI: 1.267-2.278, P < 0.001). The present results demonstrate that lower CCR is significantly associated with a higher risk of ALS.

Elevated peripheral inflammation is associated with choroid plexus enlargement in independent sporadic amyotrophic lateral sclerosis cohorts

BACKGROUND

Using neuroimaging techniques, growing evidence has suggested that the choroid plexus (CP) volume is enlarged in multiple neurodegenerative diseases, including amyotrophic lateral sclerosis (ALS). Notably, the CP has been suggested to play an important role in inflammation-induced CNS damage under disease conditions. However, to our knowledge, no study has investigated the relationships between peripheral inflammation and CP volume in sporadic ALS patients. Thus, in this study, we aimed to verify CP enlargement and explore its association with peripheral inflammation in vivo in independent ALS cohorts.

METHODS

Based on structural MRI data, CP volume was measured using Gaussian mixture models and further manually corrected in two independent cohorts of sporadic ALS patients and healthy controls (HCs). Serum inflammatory protein levels were measured using a novel high-sensitivity Olink proximity extension assay (PEA) technique. Xtreme gradient boosting (XGBoost) was used to explore the contribution of peripheral inflammatory factors to CP enlargement. Then, partial correlation analyses were performed.

RESULTS

CP volumes were significantly higher in ALS patients than in HCs in the independent cohorts. Compared with HCs, serum levels of CRP, IL-6, CXCL10, and 35 other inflammatory factors were significantly increased in ALS patients. Using the XGBoost approach, we established a model-based importance of features, and the top three predictors of CP volume in ALS patients were CRP, IL-6, and CXCL10 (with gains of 0.24, 0.18, and 0.15, respectively). Correlation analyses revealed that CRP, IL-6, and CXCL10 were significantly associated with CP volume in ALS patients (r = 0.462 ∼ 0.636, p < 0.001).

CONCLUSION

Our study is the first to reveal a consistent and replicable contribution of peripheral inflammation to CP enlargement in vivo in sporadic ALS patients. Given that CP enlargement has been recently detected in other brain diseases, these findings should consider extending to other disease conditions with a peripheral inflammatory component.

Amyotrophic Lateral Sclerosis: Insights and New Prospects in Disease Pathophysiology, Biomarkers and Therapies

Amyotrophic Lateral Sclerosis (ALS) is a severe neurodegenerative disorder marked by the gradual loss of motor neurons, leading to significant disability and eventual death. Despite ongoing research, there are still limited treatment options, underscoring the need for a deeper understanding of the disease's complex mechanisms and the identification of new therapeutic targets. This review provides a thorough examination of ALS, covering its epidemiology, pathology, and clinical features. It investigates the key molecular mechanisms, such as protein aggregation, neuroinflammation, oxidative stress, and excitotoxicity that contribute to motor neuron degeneration. The role of biomarkers is highlighted for their importance in early diagnosis and disease monitoring. Additionally, the review explores emerging therapeutic approaches, including inhibitors of protein aggregation, neuroinflammation modulators, antioxidant therapies, gene therapy, and stem cell-based treatments. The advantages and challenges of these strategies are discussed, with an emphasis on the potential for precision medicine to tailor treatments to individual patient needs. Overall, this review aims to provide a comprehensive overview of the current state of ALS research and suggest future directions for developing effective therapies.

Prognostic clinical and biological markers for amyotrophic lateral sclerosis disease progression: validation and implications for clinical trial design and analysis

BACKGROUND

With increasing recognition of the value of incorporating prognostic markers into amyotrophic lateral sclerosis (ALS) trial design and analysis plans, there is a pressing need to understand which among the prevailing clinical and biochemical markers have real value, and how they can be optimally used.

METHODS

A subset of patients with ALS recruited through the multi-center Phenotype-Genotype-Biomarker study (clinicaltrials.gov: NCT02327845) was identified as "trial-like" based on meeting common trial eligibility criteria. Clinical phenotyping was performed by evaluators trained in relevant assessments. Serum neurofilament light (NfL) and phosphorylated neurofilament heavy (pNfH), urinary p75ECD, plasma microRNA-181, and an array of biochemical and clinical measures were evaluated for their prognostic value. Associations with functional progression were estimated by random-slopes mixed models of ALS functional rating scale-revised (ALSFRS-R) score. Associations with survival were estimated by log-rank test and Cox proportional hazards regression. Potential sample size savings from adjusting for given biomarkers in a hypothetical trial were estimated.

FINDINGS

Baseline serum NfL is a powerful prognostic biomarker, predicting survival and ALSFRS-R rate of decline. Serum NfL <40 pg/mL and >100 pg/mL correspond to future ALSFRS-R slopes of ∼0.5 and ∼1.5 points/month, respectively. Serum NfL also adds value to the best available clinical predictors, encapsulated by the European Network to Cure ALS (ENCALS) predictor score. In models of functional decline, the addition of NfL yields ∼25% sample size saving above those achieved by inclusion of either clinical predictors or ENCALS score alone. The prognostic value of serum pNfH, urinary p75ECD, and plasma miR-181ab is more limited.

INTERPRETATION

Among the multitude of biomarkers considered, only blood NfL adds value to the ENCALS prediction model and should be incorporated into analysis plans for all ongoing and future ALS trials. Defined thresholds of NfL might also be used in trial design, for enrichment or stratified randomisation, to improve trial efficiency.

FUNDING

NIH (U01-NS107027, U54-NS092091). ALSA (16-TACL-242).

The role of ALDH2 rs671 polymorphism and C-reactive protein in the phenotypes of male ALS patients

Background

The aldehyde dehydrogenase 2 (ALDH2) rs671 (A) allele has been implicated in neurodegeneration, potentially through oxidative and inflammatory pathways. The study aims to investigate the effects of the ALDH2 rs671 (A) allele and high sensitivity C-reactive protein (hs-CRP) on the clinical phenotypes of amyotrophic lateral sclerosis (ALS) in male and female patients.

Methods

Clinical data and ALDH2 rs671 genotype of 143 ALS patients, including 85 males and 58 females, were collected from January 2018 to December 2022. All patients underwent assessment using the Chinese version of the Edinburgh Cognitive and Behavioral ALS Screen (ECAS). Complete blood count and metabolic profiles were measured. Clinical and laboratory parameters were compared between carriers and non-carriers of the rs671 (A) allele in males and females, respectively. The significant parameters and rs671 (A) Allele were included in multivariate linear regression models to identify potential contributors to motor and cognitive impairment. Mediation analysis was employed to evaluate any mediation effects.

Results

Male patients carrying rs671 (A) allele exhibited higher levels of hs-CRP than non-carriers (1.70 mg/L vs. 0.50 mg/L, p = 0.006). The rs671 (A) allele was identified as an independent risk factor for faster disease progression only in male patients (β = 0.274, 95% CI = 0.048-0.499, p = 0.018). The effect of the rs671 (A) allele on the executive function in male patients was fully mediated by hs-CRP (Indirect effect = -1.790, 95% CI = -4.555--0.225). No effects of the rs671 (A) allele or hs-CRP were observed in female ALS patients. The effects of the ALDH2 rs671 (A) allele and the mediating role of hs-CRP in male patients remained significant in the sensitivity analyses.

Conclusion

The ALDH2 rs671 (A) allele contributed to faster disease progression and hs-CRP mediated cognitive impairment in male ALS patients.

Establishment of a novel amyotrophic lateral sclerosis patient (TARDBP N345K/+)-derived brain microvascular endothelial cell model reveals defective Wnt/β-catenin signaling: investigating diffusion barrier dysfunction and immune cell interaction

Amyotrophic lateral sclerosis (ALS) is a major neurodegenerative disease for which there is currently no curative treatment. The blood-brain barrier (BBB), multiple physiological functions formed by mainly specialized brain microvascular endothelial cells (BMECs), serves as a gatekeeper to protect the central nervous system (CNS) from harmful molecules in the blood and aberrant immune cell infiltration. The accumulation of evidence indicating that alterations in the peripheral milieu can contribute to neurodegeneration within the CNS suggests that the BBB may be a previously overlooked factor in the pathogenesis of ALS. Animal models suggest BBB breakdown may precede neurodegeneration and link BBB alteration to the disease progression or even onset. However, the lack of a useful patient-derived model hampers understanding the pathomechanisms of BBB dysfunction and the development of BBB-targeted therapies. In this study, we differentiated BMEC-like cells from human induced pluripotent stem cells (hiPSCs) derived from ALS patients to investigate BMEC functions in ALS patients. TARDBP N345K/+ carrying patient-derived BMEC-like cells exhibited increased permeability to small molecules due to loss of tight junction in the absence of neurodegeneration or neuroinflammation, highlighting that BMEC abnormalities in ALS are not merely secondary consequences of disease progression. Furthermore, they exhibited increased expression of cell surface adhesion molecules like ICAM-1 and VCAM-1, leading to enhanced immune cell adhesion. BMEC-like cells derived from hiPSCs with other types of TARDBP gene mutations (TARDBP K263E/K263E and TARDBP G295S/G295S) introduced by genome editing technology did not show such BMEC dysfunction compared to the isogenic control. Interestingly, transactive response DNA-binding protein 43 (TDP-43) was mislocalized to cytoplasm in TARDBP N345K/+ carrying model. Wnt/β-catenin signaling was downregulated in the ALS patient (TARDBP N345K/+)-derived BMEC-like cells and its activation rescued the leaky barrier phenotype and settled down VCAM-1 expressions. These results indicate that TARDBP N345K/+ carrying model recapitulated BMEC abnormalities reported in brain samples of ALS patients. This novel patient-derived BMEC-like cell is useful for the further analysis of the involvement of vascular barrier dysfunctions in the pathogenesis of ALS and for promoting therapeutic drug discovery targeting BMEC.

Prognostic Clinical and Biological Markers for Amyotrophic Lateral Sclerosis Disease Progression: Validation and Implications for Clinical Trial Design and Analysis

Background

With increasing recognition of the value of incorporating prognostic markers into amyotrophic lateral sclerosis (ALS) trial design and analysis plans, there is a pressing need to understand which among the prevailing clinical and biochemical markers have real value, and how they can be optimally used.

Methods

A subset of patients with ALS recruited through the multi-center Phenotype-Genotype-Biomarker study (clinicaltrials.gov: NCT02327845) was identified as "trial-like" based on meeting common trial eligibility criteria. Clinical phenotyping was performed by evaluators trained in relevant assessments. Serum neurofilament light (NfL) and phosphorylated neurofilament heavy (pNfH), urinary p75ECD, plasma microRNA-181, and an array of biochemical and clinical measures were evaluated for their prognostic value. Associations with functional progression were estimated by random-slopes mixed models of ALS functional rating scale-revised (ALSFRS-R) score. Associations with survival were estimated by log-rank test and Cox proportional hazards regression. Potential sample size savings from adjusting for given biomarkers in a hypothetical trial were estimated.

Findings

Baseline serum NfL is a powerful prognostic biomarker, predicting survival and ALSFRS-R rate of decline. Serum NfL <40pg/ml and >100pg/ml correspond to future ALSFRS-R slopes of ~0.5 and 1.5 points/month, respectively. Serum NfL also adds value to the best available clinical predictors, encapsulated by the European Network to Cure ALS (ENCALS) predictor score. In models of functional decline, the addition of NfL yields ~25% sample size saving above those achieved by inclusion of either clinical predictors or ENCALS score alone. The prognostic value of serum pNfH, urinary p75ECD, and plasma miR-181ab is more limited.

Interpretation

Among the multitude of biomarkers considered, only blood NfL adds value to the ENCALS prediction model and should be incorporated into analysis plans for all ongoing and future ALS trials. Defined thresholds of NfL might also be used in trial design, for enrichment or stratified randomisation, to improve trial efficiency.

Funding

NIH (U01-NS107027, U54-NS092091). ALSA (16-TACL-242).

Meta-analysis of differential gene expression in lower motor neurons isolated by laser capture microdissection from post-mortem ALS spinal cords

Introduction

ALS is a fatal neurodegenerative disease for which underlying mechanisms are incompletely understood. The motor neuron is a central player in ALS pathogenesis but different transcriptome signatures have been derived from bulk analysis of post-mortem tissue and iPSC-derived motor neurons (iPSC-MNs).

Methods

This study performed a meta-analysis of six gene expression studies (microarray and RNA-seq) in which laser capture microdissection (LCM) was used to isolate lower motor neurons from post-mortem spinal cords of ALS and control (CTL) subjects. Differentially expressed genes (DEGs) with consistent ALS versus CTL expression differences across studies were identified.

Results

The analysis identified 222 ALS-increased DEGs (FDR <0.10, SMD >0.80) and 278 ALS-decreased DEGs (FDR <0.10, SMD < -0.80). ALS-increased DEGs were linked to PI3K-AKT signaling, innate immunity, inflammation, motor neuron differentiation and extracellular matrix. ALS-decreased DEGs were associated with the ubiquitin-proteosome system, microtubules, axon growth, RNA-binding proteins and synaptic membrane. ALS-decreased DEG mRNAs frequently interacted with RNA-binding proteins (e.g., FUS, HuR). The complete set of DEGs (increased and decreased) overlapped significantly with genes near ALS-associated SNP loci (p < 0.01). Transcription factor target motifs with increased proximity to ALS-increased DEGs were identified, most notably DNA elements predicted to interact with forkhead transcription factors (e.g., FOXP1) and motor neuron and pancreas homeobox 1 (MNX1). Some of these DNA elements overlie ALS-associated SNPs within known enhancers and are predicted to have genotype-dependent MNX1 interactions. DEGs were compared to those identified from SOD1-G93A mice and bulk spinal cord segments or iPSC-MNs from ALS patients. There was good correspondence with transcriptome changes from SOD1-G93A mice (r ≤ 0.408) but most DEGs were not differentially expressed in bulk spinal cords or iPSC-MNs and transcriptome-wide effect size correlations were weak (bulk tissue: r ≤ 0.207, iPSC-MN: r ≤ 0.037).

Conclusion

This study defines a robust transcriptome signature from LCM-based motor neuron studies of post-mortem tissue from ALS and CTL subjects. This signature differs from those obtained from analysis of bulk spinal cord segments and iPSC-MNs. Results provide insight into mechanisms underlying gene dysregulation in ALS and highlight connections between these mechanisms, ALS genetics, and motor neuron biology.

Unraveling the Heterogeneity of ALS-A Call to Redefine Patient Stratification for Better Outcomes in Clinical Trials

Despite tremendous efforts in basic research and a growing number of clinical trials aiming to find effective treatments, amyotrophic lateral sclerosis (ALS) remains an incurable disease. One possible reason for the lack of effective causative treatment options is that ALS may not be a single disease entity but rather may represent a clinical syndrome, with diverse genetic and molecular causes, histopathological alterations, and subsequent clinical presentations contributing to its complexity and variability among individuals. Defining a way to subcluster ALS patients is becoming a central endeavor in the field. Identifying specific clusters and applying them in clinical trials could enable the development of more effective treatments. This review aims to summarize the available data on heterogeneity in ALS with regard to various aspects, e.g., clinical, genetic, and molecular.

Immune-mediated diseases are associated with a higher risk of ALS incidence: a prospective cohort study from the UK Biobank

Objective

The occurrence of immune-mediated diseases (IMDs) in amyotrophic lateral sclerosis (ALS) patients is widely reported. However, whether IMDs and ALS is a simple coexistence or if there exists causal relationships between the two has been a subject of great interest to researchers.

Methods

A total of 454,444 participants from the prospective cohort of UK Biobank were recruited to investigate the longitudinal association between IMDs and ALS. Previously any IMDs and organ specific IMDs were analyzed in relation to the following incident ALS by Cox-proportional hazard models. Subgroup analyses were performed to explore the covariates of these relationships.

Results

After adjusting for potential covariates, the multivariate analysis showed that any IMDs were associated with an increased risk of ALS incidence (HR:1.42, 95%CI:1.03-1.94). IMDs of the endocrine-system and the intestinal-system were associated with increased risk of ALS incidence (endocrine-system IMDs: HR:3.01, 95%CI:1.49-6.06; intestinal system IMDs: HR:2.07, 95%CI: 1.14-3.77). Subgroup analyses revealed that immune burden, including IMD duration and the severity of inflammation had specific effects on the IMD-ALS association. In participants with IMD duration≥10 years or CRP≥1.3mg/L or females, previous IMDs increased the risk of incident ALS; however, in participants with IMD duration <10 years or CRP<1.3mg/L or males, IMDs had no effect on incident ALS.

Interpretation

Our study provides evidence that previous any IMDs and endocrine-system and the intestinal-system specific IMDs are associated with an increased risk of developing ALS in females, but not in males.

Supplementation of probiotic Bifidobacterium breve Bif11 reverses neurobehavioural deficits, inflammatory changes and oxidative stress in Parkinson's disease model

Human gut microbiota are thought to affect different physiological processes in the body, including brain functions. Gut dysbiosis has been linked to the progression of Parkinson's disease (PD) and thus, restoring the healthy gut microbiota with supplementation of putative probiotic strains can confer some benefits in PD. In the current study, we explored the neuroprotective potential of Bifidobacterium breve Bif11 supplementation in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine hydrochloride (MPTP) treated female Sprague Dawley rats. This study investigated the behavioural, molecular and biochemical parameters in the MPTP rat model. A pharmacological intervention of Bif11 at doses of 1 × 1010 CFU and 2 × 1010 CFU for 21 days was found to attenuate the cognitive and motor changes in the MPTP rat model. Furthermore, it also increased the tyrosine hydroxylase levels, reduced pro-inflammatory markers and decreased oxidative and nitrosative stress in the mid brain of MPTP-lesioned rats. Bif11 supplementation even restored the levels of short-chain fatty acids and decreased intestinal epithelial permeability in MPTP-induced PD model rats. In summary, these findings demonstrate that B. breve Bif11 has the potential to ameliorate symptoms of PD. However, this therapy needs to be further investigated with in-depth mechanistic insights in the future for the treatment of PD.

Effects of tofersen treatment in patients with SOD1-ALS in a "real-world" setting - a 12-month multicenter cohort study from the German early access program

Background

In April 2023, the antisense oligonucleotide tofersen was approved by the U.S. Food and Drug Administration (FDA) for treatment of SOD1-amyotrophic lateral sclerosis (ALS), after a decrease of neurofilament light chain (NfL) levels had been demonstrated.

Methods

Between 03/2022 and 04/2023, 24 patients with SOD1-ALS from ten German ALS reference centers were followed-up until the cut-off date for ALS functional rating scale revised (ALSFRS-R), progression rate (loss of ALSFRS-R/month), NfL, phosphorylated neurofilament heavy chain (pNfH) in cerebrospinal fluid (CSF), and adverse events.

Findings

During the observation period, median ALSFRS-R decreased from 38.0 (IQR 32.0-42.0) to 35.0 (IQR 29.0-42.0), corresponding to a median progression rate of 0.11 (IQR -0.09 to 0.32) points of ALSFRS-R lost per month. Median serum NfL declined from 78.0 pg/ml (IQR 37.0-147.0 pg/ml; n = 23) to 36.0 pg/ml (IQR 22.0-65.0 pg/ml; n = 23; p = 0.02), median pNfH in CSF from 2226 pg/ml (IQR 1061-6138 pg/ml; n = 18) to 1151 pg/ml (IQR 521-2360 pg/ml; n = 18; p = 0.02). In the CSF, we detected a pleocytosis in 73% of patients (11 of 15) and an intrathecal immunoglobulin synthesis (IgG, IgM, or IgA) in 9 out of 10 patients. Two drug-related serious adverse events were reported.

Interpretation

Consistent with the VALOR study and its Open Label Extension (OLE), our results confirm a reduction of NfL serum levels, and moreover show a reduction of pNfH in CSF. The therapy was safe, as no persistent symptoms were observed. Pleocytosis and Ig synthesis in CSF with clinical symptoms related to myeloradiculitis in two patients, indicate the potential of an autoimmune reaction.

Funding

No funding was received towards this study.

The value of routine blood work-up in clinical stratification and prognosis of patients with amyotrophic lateral sclerosis

BACKGROUND

There is an unmet need in amyotrophic lateral sclerosis (ALS) to provide specific biomarkers for the disease. Due to their easy availability, we aimed to investigate whether routine blood parameters provide useful clues for phenotypic classification and disease prognosis.

METHODS

We analyzed a large inpatient cohort of 836 ALS patients who underwent deep phenotyping with evaluation of the clinical and neurophysiological burden of upper (UMN) and lower (LMN) motor neuron signs. Disability and progression rate were measured through the revised ALS Functional Rating Scale (ALSFRS-R) and its changes during time. Cox regression analysis was performed to assess survival associations.

RESULTS

Creatinine significantly correlated with LMN damage (r = 0.38), active (r = 0.18) and chronic (r = 0.24) denervation and baseline ALSFRS-R (r = 0.33). Creatine kinase (CK), alanine (ALT) and aspartate (AST) transaminases correlated with active (r = 0.35, r = 0.27, r = 0.24) and chronic (r = 0.37, r = 0.20, r = 0.19) denervation, while albumin and C-reactive protein significantly correlated with LMN score (r = 0.20 and r = 0.17). Disease progression rate showed correlations with chloride (r = -0.19) and potassium levels (r = -0.16). After adjustment for known prognostic factors, total protein [HR 0.70 (95% CI 0.57-0.86)], creatinine [HR 0.86 (95% CI 0.81-0.92)], chloride [HR 0.95 (95% CI 0.92-0.99)], lactate dehydrogenase [HR 0.99 (95% CI 0.99-0.99)], and AST [HR 1.02 (95% CI 1.01-1.02)] were independently associated with survival.

CONCLUSIONS

Creatinine is a reliable biomarker for ALS, associated with clinical features, disability and survival. Markers of nutrition/inflammation may offer additional prognostic information and partially correlate with clinical features. AST and chloride could further assist in predicting progression rate and survival.

Eosinophils at diagnosis are elevated in amyotrophic lateral sclerosis

Introduction

Amyotrophic lateral sclerosis (ALS) is a rare, devastating neurodegenerative disease that affects upper and lower motor neurons. To date, no effective treatment or reliable biomarker for ALS has been developed. In recent years, many factors have been proposed as possible biomarkers of ALS; however, no consensus has been reached. Therefore, a reliable biomarker is urgently needed. Eosinophils may play a crucial role in healthy humans and diseases, and serve as a biomarker for many chronic diseases.

Methods

Routine blood test results were collected from 66 healthy controls and 59 patients with ALS. The percentages and total numbers of each cell population were analyzed, and the correlation between these indicators and patient ALS functional rating scale-revised (ALSFRS-R) score or disease progression rate (ΔFS score) was analyzed.

Results

Compared to healthy controls, the number of blood leukocytes, neutrophils, monocytes, and basophils was significantly decreased in patients with ALS (p = 0.002, p = 0.001, p = 0.049, and p < 0.0001, respectively). There was an increase in the number of eosinophils (p < 0.0001), but no difference in the number of lymphocytes between patients with ALS and healthy controls was found (p = 0.563). Compared to healthy controls, the percentage of neutrophils was decreased and the percentage of lymphocytes and eosinophils was increased in patients with ALS (p = 0.01, p = 0.012, and p = 0.001, respectively). There was no difference between patients with ALS and healthy controls in the percentage of monocytes and basophils (p = 0.622 and p = 0.09, respectively). However, only the percentage and number of eosinophils had a correlation with the ΔFS score. Further multivariate analysis revealed a significant correlation between the disease duration, eosinophil count and percentage, and the disease progression rate (p < 0.0001, p = 0.048, and p = 0.023, respectively). The neutrophil-to-eosinophil ratio (NER), lymphocyte-to-eosinophil ratio (LER), and monocyte-to-eosinophil ratio (MER) were significantly lower in patients with ALS than in healthy controls. However, only the LER was significantly correlated with the ΔFS score.

Conclusion

These observations implicate neutrophils, lymphocytes, and eosinophils as important factors, and increasing eosinophil counts were negatively correlated with the ΔFS score in patients with ALS.

Association Between Fat Depletion and Prognosis of Amyotrophic Lateral Sclerosis: CT-Based Body Composition Analysis

OBJECTIVE

The purpose of this study was to present the results of our investigation of the prognostic value of adipopenia and sarcopenia in patients with amyotrophic lateral sclerosis (ALS).

METHODS

Consecutive patients with ALS with abdominal computed tomography (CT) were retrospectively identified at a single tertiary hospital between January 2010 and July 2021. Deep learning-based volumetric CT body composition analysis software was used to obtain abdominal waist fat volume, fat attenuation, and skeletal muscle area at the L3 level, then normalized to the fat volume index (FVI) and skeletal muscle index (SMI). Adipopenia and sarcopenia were defined as the sex-specific lowest quartile and SMI reference values, respectively. The associations of CT-derived body composition parameters with clinical variables, such as body mass index (BMI) and creatinine, were evaluated by Pearson correlation analyses, and associations with survival were assessed using the multivariable Cox regression analysis.

RESULTS

Eighty subjects (40 men, 65.5 ± 9.4 years of age) were investigated (median interval between disease onset and CT examination = 25 months). The mean BMI at the CT examination was 20.3 ± 4.3 kg/m2 . The BMI showed a positive correlation with both FVI (R = 0.70, p < 0.001) and SMI (R = 0.63, p < 0.001), and the serum creatinine level was associated with SMI (R = 0.68, p < 0.001). After adjusting for sex, age, King's stage, BMI, creatinine, progression rate, and sarcopenia, adipopenia was associated with shorter survival (hazard ratio [HR] = 5.94, 95% confidence interval [CI] = 1.01, 35.0, p = 0.049). In a subgroup analysis for subjects with nutritional failure (stage 4a), the HR of adipopenia was 15.1 (95% CI = 2.45, 93.4, p = 0.003).

INTERPRETATION

Deep learning-based CT-derived adipopenia in patients with ALS is an independent poor prognostic factor for survival. ANN NEUROL 2023;94:1116-1125.

From Recognition to Remedy: The Significance of Biomarkers in Neurodegenerative Disease Pathology

With the inexorable aging of the global populace, neurodegenerative diseases (NDs) like Alzheimer's disease (AD), Parkinson's disease (PD), and amyotrophic lateral sclerosis (ALS) pose escalating challenges, which are underscored by their socioeconomic repercussions. A pivotal aspect in addressing these challenges lies in the elucidation and application of biomarkers for timely diagnosis, vigilant monitoring, and effective treatment modalities. This review delineates the quintessence of biomarkers in the realm of NDs, elucidating various classifications and their indispensable roles. Particularly, the quest for novel biomarkers in AD, transcending traditional markers in PD, and the frontier of biomarker research in ALS are scrutinized. Emergent susceptibility and trait markers herald a new era of personalized medicine, promising enhanced treatment initiation especially in cases of SOD1-ALS. The discourse extends to diagnostic and state markers, revolutionizing early detection and monitoring, alongside progression markers that unveil the trajectory of NDs, propelling forward the potential for tailored interventions. The synergy between burgeoning technologies and innovative techniques like -omics, histologic assessments, and imaging is spotlighted, underscoring their pivotal roles in biomarker discovery. Reflecting on the progress hitherto, the review underscores the exigent need for multidisciplinary collaborations to surmount the challenges ahead, accelerate biomarker discovery, and herald a new epoch of understanding and managing NDs. Through a panoramic lens, this article endeavors to provide a comprehensive insight into the burgeoning field of biomarkers in NDs, spotlighting the promise they hold in transforming the diagnostic landscape, enhancing disease management, and illuminating the pathway toward efficacious therapeutic interventions.

Neutrophils Are Associated with Higher Risk of Incident Amyotrophic Lateral Sclerosis in a BMI- and Age-Dependent Manner

OBJECTIVE

Peripheral immune markers have been associated with the progression and prognosis of amyotrophic lateral sclerosis (ALS). However, whether dysregulation of peripheral immunity is a risk factor for ALS or a consequence of motor neuron degeneration has not yet been clarified. We aimed to identify longitudinal associations between prediagnostic peripheral immunity and the risk of incident ALS.

METHODS

A total of 345,000 individuals from the UK Biobank between 2006 and 2010 were included at the baseline. The counts of peripheral immune markers (neutrophils, lymphocytes, monocytes, platelets, and CRP) and its derived metrics (neutrophil-to-lymphocyte ratio [NLR], platelet-to-lymphocyte ratio [PLR], lymphocyte-to-monocyte ratio [LMR], and systemic immune-inflammation index [SII]) were analyzed in relation to the following incident ALS by Cox proportional hazard models. Subgroup and interaction analyses were performed to explore the covariates of these relationships further.

RESULTS

After adjusting for all covariates, the multivariate analysis showed that high neutrophil counts and their derived metrics (NLR and SII) were associated with an increased risk of ALS incidence (per SD increment hazard ratio [HR] = 1.15, 95% confidence interval [CI] = 1.02-1.29 for neutrophils; HR = 1.15, 95% CI = 1.03-1.28 for NLR; and HR = 1.17, 95% CI = 1.05-1.30 for SII). Subgroup and interaction analyses revealed that body mass index (BMI) and age had specific effects on this association. In participants with BMI ≥ 25 or age < 65 years, higher neutrophil counts, and their metrics increased the risk of incident ALS; however, in participants with BMI < 25 or age ≥ 65 years, neutrophils had no effect on incident ALS.

INTERPRETATION

Our study provides evidence that increased neutrophil levels and neutrophil-derived metrics (NLR and SII) are associated with an increased risk of developing ALS. ANN NEUROL 2023;94:942-954.

Systemic inflammation and subsequent risk of amyotrophic lateral sclerosis: Prospective cohort study

BACKGROUND

While systemic inflammation has been implicated in the etiology of selected neurodegenerative disorders, its role in the development of amyotrophic lateral sclerosis (ALS), a condition with high case-fatality, is untested. Accordingly, we quantified the relationship of C-reactive protein (CRP), an acute-phase reactant and marker of systemic inflammation, with subsequent ALS occurrence.

METHODS

We used data from UK Biobank, a prospective cohort study of 502,649 participants who were aged 37 to 73 years when examined at research centers between 2006 and 2010. Venous blood was collected at baseline in the full cohort and assayed for CRP, and repeat measurement was made 3-7 years later in a representative subgroup (N = 14,514) enabling correction for regression dilution. ALS was ascertained via national hospitalization and mortality registries until 2021. We computed multivariable hazard ratios with accompanying 95% confidence intervals for log-transformed CRP expressed as standard deviation and tertiles.

RESULTS

In an analytical sample of 400,884 initially ALS-free individuals (218,203 women), a mean follow-up of 12 years gave rise to 231 hospitalizations and 223 deaths ascribed to ALS. After adjustment for covariates which included health behaviors, comorbidity, and socio-economic status, a one standard deviation higher log-CRP was associated with elevated rates of both ALS mortality (hazard ratios; 95% confidence intervals: 1.32; 1.13, 1.53) and hospitalizations (1.20; 1.00, 1.39). There was evidence of dose-response effects across tertiles of CRP for both outcomes (p for trend ≤ 0.05). Correction for regression dilution led to a strengthening of the relationship with CRP for both mortality (1.62; 1.27, 2.08) and hospitalizations (1.37; 1.05, 1.76).

CONCLUSIONS

Higher levels of CRP, a blood-based biomarker widely captured in clinical practice, is associated with moderately increased future risk of amyotrophic lateral sclerosis.

Rab Geranylgeranyltransferase Subunit Beta as a Potential Indicator to Assess the Progression of Amyotrophic Lateral Sclerosis

BACKGROUND

Currently, there is no effective treatment for amyotrophic lateral sclerosis (ALS), a devastating neurodegenerative disorder. Many biomarkers have been proposed, but because ALS is a clinically heterogeneous disease with an unclear etiology, biomarker discovery for ALS has been challenging due to the lack of specificity of these biomarkers. In recent years, the role of autophagy in the development and treatment of ALS has become a research hotspot. In our previous studies, we found that the expression of RabGGTase (low RABGGTB expression and no change in RABGGTA) is lower in the lumbar and thoracic regions of spinal cord motoneurons in SOD1G93A mice compared with WT (wild-type) mice groups, and upregulation of RABGGTB promoted prenylation modification of Rab7, which promoted autophagy to protect neurons by degrading SOD1. Given that RabGGTase is associated with autophagy and autophagy is associated with inflammation, and based on the above findings, since peripheral blood mononuclear cells are readily available from patients with ALS, we proposed to investigate the expression of RabGGTase in peripheral inflammatory cells.

METHODS

Information and venous blood were collected from 86 patients diagnosed with ALS between January 2021 and August 2023. Flow cytometry was used to detect the expression of RABGGTB in monocytes from peripheral blood samples collected from patients with ALS and healthy controls. Extracted peripheral blood mononuclear cells (PBMCs) were differentiated in vitro into macrophages, and then the expression of RABGGTB was detected by immunofluorescence. RABGGTB levels in patients with ALS were analyzed to determine their impact on disease progression.

RESULTS

Using flow cytometry in monocytes and immunofluorescence in macrophages, we found that RABGGTB expression in the ALS group was significantly higher than in the control group. Age, sex, original location, disease course, C-reactive protein (CRP), and interleukin-6 (IL-6) did not correlate with the ALS functional rating scale-revised (ALSFRS-R), whereas the RABGGTB level was significantly correlated with the ALSFRS-R. In addition, multivariate analysis revealed a significant correlation between RABGGTB and ALSFRS-R score. Further analysis revealed a significant correlation between RABGGTB expression levels and disease progression levels (ΔFS).

CONCLUSIONS

The RABGGTB level was significantly increased in patients with ALS compared with healthy controls. An elevated RABGGTB level in patients with ALS is associated with the rate of progression in ALS, suggesting that elevated RABGGTB levels in patients with ALS may serve as an indicator for tracking ALS progression.

Urinary biomarkers for amyotrophic lateral sclerosis: candidates, opportunities and considerations

Amyotrophic lateral sclerosis is a relentless neurodegenerative disease that is mostly fatal within 3-5 years and is diagnosed on evidence of progressive upper and lower motor neuron degeneration. Around 15% of those with amyotrophic lateral sclerosis also have frontotemporal degeneration, and gene mutations account for ∼10%. Amyotrophic lateral sclerosis is a variable heterogeneous disease, and it is becoming increasingly clear that numerous different disease processes culminate in the final degeneration of motor neurons. There is a profound need to clearly articulate and measure pathological process that occurs. Such information is needed to tailor treatments to individuals with amyotrophic lateral sclerosis according to an individual's pathological fingerprint. For new candidate therapies, there is also a need for methods to select patients according to expected treatment outcomes and measure the success, or not, of treatments. Biomarkers are essential tools to fulfil these needs, and urine is a rich source for candidate biofluid biomarkers. This review will describe promising candidate urinary biomarkers of amyotrophic lateral sclerosis and other possible urinary candidates in future areas of investigation as well as the limitations of urinary biomarkers.

C-Reactive Protein: Pathophysiology, Diagnosis, False Test Results and a Novel Diagnostic Algorithm for Clinicians

The current literature provides a body of evidence on C-Reactive Protein (CRP) and its potential role in inflammation. However, most pieces of evidence are sparse and controversial. This critical state-of-the-art monography provides all the crucial data on the potential biochemical properties of the protein, along with further evidence on its potential pathobiology, both for its pentameric and monomeric forms, including information for its ligands as well as the possible function of autoantibodies against the protein. Furthermore, the current evidence on its potential utility as a biomarker of various diseases is presented, of all cardiovascular, respiratory, hepatobiliary, gastrointestinal, pancreatic, renal, gynecological, andrological, dental, oral, otorhinolaryngological, ophthalmological, dermatological, musculoskeletal, neurological, mental, splenic, thyroid conditions, as well as infections, autoimmune-supposed conditions and neoplasms, including other possible factors that have been linked with elevated concentrations of that protein. Moreover, data on molecular diagnostics on CRP are discussed, and possible etiologies of false test results are highlighted. Additionally, this review evaluates all current pieces of evidence on CRP and systemic inflammation, and highlights future goals. Finally, a novel diagnostic algorithm to carefully assess the CRP level for a precise diagnosis of a medical condition is illustrated.

Neuroinflammatory Pathways in the ALS-FTD Continuum: A Focus on Genetic Variants

Amyotrophic Lateral Sclerosis (ALS) and Frontotemporal dementia (FDT) are progressive neurodegenerative disorders that, in several cases, overlap in clinical presentation, and genetic and pathological disease mechanisms. About 10-15% of ALS cases and up to 40% of FTD are familial, usually with dominant traits. ALS and FTD, in several cases, share common gene mutations, such as in C9ORF72, TARDBP, SQSTM-1, FUS, VCP, CHCHD10, and TBK-1. Also, several mechanisms are involved in ALS and FTD pathogenesis, such as protein misfolding, oxidative stress, and impaired axonal transport. In addition, neuroinflammation and neuroinflammatory cells, such as astrocytes, oligodendrocytes, microglia, and lymphocytes and, overall, the cellular microenvironment, have been proposed as pivotal players in the pathogenesis the ALS-FTD spectrum disorders. This review overviews the current evidence regarding neuroinflammatory markers in the ALS/FTD continuum, focusing on the neuroinflammatory pathways involved in the genetic cases, moving from post-mortem reports to in vivo biofluid and neuroimaging data. We further discuss the potential link between genetic and autoimmune disorders and potential therapeutic implications.

Associations of Chinese visceral adiposity index and new-onset stroke in middle-aged and older Chinese adults: an observational study

BACKGROUND

Stroke represents the second most prevalent contributor to global mortality. The Chinese Visceral Adiposity Index (CVAI) serves as an established metric for assessing visceral adiposity in the Chinese population, exhibiting prognostic capabilities. This investigation aimed to explore the association of CVAI and new-onset stroke among middle-aged and older Chinese populations.

METHODS

The study employed data from the 2011 and 2018 China Health and Retirement Longitudinal Study (CHARLS) to assess the association of CVAI and the incidence of new-onset stroke. Utilizing a directed acyclic graph (DAG), 10 potential confounders were identified. Moreover, to explore the association between CVAI and new-onset stroke, three multifactor logistic regression models were constructed, accounting for the identified confounders and mitigating their influence on the findings.

RESULTS

The study comprised 7070 participants, among whom 417 (5.9%) experienced new-onset strokes. After controlling for confounding variables, regression analysis suggested that the new-onset stroke's highest risk was linked to the fourth quartile (Q4) of the CVAI, with an odds ratio (OR) of 2.33 and a 95% confidence interval (CI) of 1.67-3.28. The decision tree analysis demonstrated a heightened probability of new-onset stroke among hypertensive individuals with a CVAI equal to or greater than 83, coupled with a C-reactive protein level no less than 1.1 mg/l. Age seemed to have a moderating influence on the CVAI and new-onset stroke association, exhibiting a more prominent interaction effect in participants under 60 years.

CONCLUSIONS

In middle-aged and older Chinese populations, a linear relationship was discerned between CVAI and the probability of new-onset stroke. CVAI provides a predictive framework for stroke incidence in this demographic, laying the groundwork for more sophisticated risk prediction models that improve the precision and specificity of stroke risk evaluations.

Phase 1/2a clinical trial in ALS with ropinirole, a drug candidate identified by iPSC drug discovery

iPSC-based drug discovery led to a phase 1/2a trial of ropinirole in ALS. 20 participants with sporadic ALS received ropinirole or placebo for 24 weeks in the double-blind period to evaluate safety, tolerability, and therapeutic effects. Adverse events were similar in both groups. During the double-blind period, muscle strength and daily activity were maintained, but a decline in the ALSFRS-R, which assesses the functional status of ALS patients, was not different from that in the placebo group. However, in the open-label extension period, the ropinirole group showed significant suppression of ALSFRS-R decline and an additional 27.9 weeks of disease-progression-free survival. iPSC-derived motor neurons from participants showed dopamine D2 receptor expression and a potential involvement of the SREBP2-cholesterol pathway in therapeutic effects. Lipid peroxide represents a clinical surrogate marker to assess disease progression and drug efficacy. Limitations include small sample sizes and high attrition rates in the open-label extension period, requiring further validation.

Biofluid Biomarkers in the Prognosis of Amyotrophic Lateral Sclerosis: Recent Developments and Therapeutic Applications

Amyotrophic lateral sclerosis is a neurodegenerative disease characterized by the degeneration of motor neurons for which effective therapies are lacking. One of the most explored areas of research in ALS is the discovery and validation of biomarkers that can be applied to clinical practice and incorporated into the development of innovative therapies. The study of biomarkers requires an adequate theoretical and operational framework, highlighting the "fit-for-purpose" concept and distinguishing different types of biomarkers based on common terminology. In this review, we aim to discuss the current status of fluid-based prognostic and predictive biomarkers in ALS, with particular emphasis on those that are the most promising ones for clinical trial design and routine clinical practice. Neurofilaments in cerebrospinal fluid and blood are the main prognostic and pharmacodynamic biomarkers. Furthermore, several candidates exist covering various pathological aspects of the disease, such as immune, metabolic and muscle damage markers. Urine has been studied less often and should be explored for its possible advantages. New advances in the knowledge of cryptic exons introduce the possibility of discovering new biomarkers. Collaborative efforts, prospective studies and standardized procedures are needed to validate candidate biomarkers. A combined biomarkers panel can provide a more detailed disease status.

Systemic inflammation and subsequent risk of amyotrophic lateral sclerosis: prospective cohort study

Importance

While systemic inflammation has been implicated in the aetiology of selected neurodegenerative disorders, its role in the development of amyotrophic lateral sclerosis (ALS) is untested.

Objective

To quantify the relationship of C-reactive protein (CRP), an acute-phase reactant and marker of systemic inflammation, with ALS occurrence.

Design Setting Participants

UK Biobank, a prospective cohort study of 502,649 participants who were aged 37 to 73 years when examined at research centres between 2006 and 2010.

Exposure

Venous blood was collected at baseline in the full cohort and assayed for CRP. Repeat measurement was made 3-7 years later in a representative subgroup (N=14,514) enabling correction for regression dilution.

Main Outcomes and Measures

ALS as ascertained via national hospitalisation and mortality registries. We computed multi-variable hazard ratios with accompanying 95% confidence intervals for log-transformed CRP expressed as standard deviation and tertiles.

Results

In an analytical sample of 400,884 individuals (218,203 women), a mean follow-up of 12 years gave rise to 231 hospitalisations and 223 deaths ascribed to ALS. After adjustment for covariates which included health behaviours, comorbidity, and socio-economic status, a one standard deviation higher log-CRP was associated with elevated rates of both ALS mortality (hazard ratios; 95% confidence intervals: 1.32; 1.13, 1.53) and hospitalisations (1.20; 1.00, 1.39). There was evidence of dose-response effects across tertiles of CRP for both outcomes (p for trend≤0.05). Correction for regression dilution led to a strengthening of the relationship with CRP for both mortality (1.62; 1.27, 2.08) and hospitalisations (1.37; 1.05, 1.76) ascribed to ALS.

Conclusions and Relevance

Higher levels of CRP, a blood-based biomarker widely captured in clinical practice, were associated with a higher subsequent risk of ALS.

Key Points

Question: Is C-reactive protein (CRP), a marker of systemic inflammation widely used in clinical practice, associated with later risk of amyotrophic lateral sclerosis (ALS)?Findings: Following 11 years disease surveillance in 400,884 individuals (218,203 women), after adjustment for covariates and correction for regression dilution, a one standard deviation higher CRP levels were associations with both mortality (hazard ratio; 95% confidence interval: 1.62; 1.27, 2.08) and hospitalisations (1.37; 1.05, 1.76) ascribed to ALS.Meaning: In the present study, CRP has a dose-response relationship with the risk of later ALS.

Blood-CNS barrier dysfunction in amyotrophic lateral sclerosis: Proposed mechanisms and clinical implications

There is strong evidence for blood-brain and blood-spinal cord barrier dysfunction at the early stages of many neurodegenerative diseases, including amyotrophic lateral sclerosis (ALS). Since impairment of the blood-central nervous system barrier (BCNSB) occurs during the pre-symptomatic stages of ALS, the mechanisms underlying this pathology are likely also involved in the ALS disease process. In this review, we explore how drivers of ALS disease, particularly mitochondrial dysfunction, astrocyte pathology and neuroinflammation, may contribute to BCNSB impairment. Mitochondria are highly abundant in BCNSB tissue and mitochondrial dysfunction in ALS contributes to motor neuron death. Likewise, astrocytes adopt key physical, transport and metabolic functions at the barrier, many of which are impaired in ALS. Astrocytes also show raised expression of inflammatory markers in ALS and ablating ALS-causing transgenes in astrocytes slows disease progression. In addition, key drivers of neuroinflammation, including TAR DNA-binding protein 43 (TDP-43) pathology, matrix metalloproteinase activation and systemic inflammation, affect BCNSB integrity in ALS. Finally, we discuss the translational implications of BCNSB dysfunction in ALS, including the development of biomarkers for disease onset and progression, approaches aimed at restoring BCNSB integrity and in vitro modelling of the neurogliovascular system.

Neurogenetic motor disorders

Advances in the field of neurogenetics have practical applications in rapid diagnosis on blood and body fluids to extract DNA, obviating the need for invasive investigations. The ability to obtain a presymptomatic diagnosis through genetic screening and biomarkers can be a guide to life-saving disease-modifying therapy or enzyme replacement therapy to compensate for the deficient disease-causing enzyme. The benefits of a comprehensive neurogenetic evaluation extend to family members in whom identification of the causal gene defect ensures carrier detection and at-risk counseling for future generations. This chapter explores the many facets of the neurogenetic evaluation in adult and pediatric motor disorders as a primer for later chapters in this volume and a roadmap for the future applications of genetics in neurology.

Amyotrophic lateral sclerosis

The scientific landscape surrounding amyotrophic lateral sclerosis has shifted immensely with a number of well-defined ALS disease-causing genes, each with related phenotypical and cellular motor neuron processes that have come to light. Yet in spite of decades of research and clinical investigation, there is still no etiology for sporadic amyotrophic lateral sclerosis, and treatment options even for those with well-defined familial syndromes are still limited. This chapter provides a comprehensive review of the genetic basis of amyotrophic lateral sclerosis, highlighting factors that contribute to its heritability and phenotypic manifestations, and an overview of past, present, and upcoming therapeutic strategies.

Inflammatory checkpoints in amyotrophic lateral sclerosis: From biomarkers to therapeutic targets

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease characterized by progressive motor neuron damage. Due to the complexity of the ALS, so far the etiology and underlying pathogenesis of sporadic ALS are not completely understood. Recently, many studies have emphasized the role of inflammatory networks, which are comprised of various inflammatory molecules and proteins in the pathogenesis of ALS. Inflammatory molecules and proteins may be used as independent predictors of patient survival and might be used in patient stratification and in evaluating the therapeutic response in clinical trials. This review article describes the latest advances in various inflammatory markers in ALS and its animal models. In particular, this review discusses the role of inflammatory molecule markers in the pathogenesis of the disease and their relationship with clinical parameters. We also highlight the advantages and disadvantages of applying inflammatory markers in clinical manifestations, animal studies, and drug clinical trials. Further, we summarize the potential application of some inflammatory biomarkers as new therapeutic targets and therapeutic strategies, which would perhaps expand the therapeutic interventions for ALS.

Biomarkers and molecular mechanisms of Amyotrophic Lateral Sclerosis

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease in adults involving non-demyelinating motor disorders. About 90% of ALS cases are sporadic, while 10-12% of cases are due to some genetic reasons. Mutations in superoxide dismutase 1 (SOD1), TAR, c9orf72 (chromosome 9 open reading frame 72) and VAPB genes are commonly found in ALS patients. Therefore, the mechanism of ALS development involves oxidative stress, endoplasmic reticulum stress, glutamate excitotoxicity and aggregation of proteins, neuro-inflammation and defective RNA function. Cholesterol and LDL/HDL levels are also associated with ALS development. As a result, sterols could be a suitable biomarker for this ailment. The main mechanisms of ALS development are reticulum stress, neuroinflammation and RNA metabolism. The multi-nature development of ALS makes it more challenging to pinpoint a treatment.

Label-free fibre optic Raman spectroscopy with bounded simplex-structured matrix factorization for the serial study of serum in amyotrophic lateral sclerosis

Amyotrophic lateral sclerosis (ALS) is an incurable neurodegenerative disease in urgent need of disease biomarkers for the assessment of promising therapeutic candidates in clinical trials. Raman spectroscopy is an attractive technique for identifying disease related molecular changes due to its simplicity. Here, we describe a fibre optic fluid cell for undertaking spontaneous Raman spectroscopy studies of human biofluids that is suitable for use away from a standard laboratory setting. Using this system, we examined serum obtained from patients with ALS at their first presentation to our centre (n = 66) and 4 months later (n = 27). We analysed Raman spectra using bounded simplex-structured matrix factorization (BSSMF), a generalisation of non-negative matrix factorisation which uses the distribution of the original data to limit the factorisation modes (spectral patterns). Biomarkers associated with ALS disease such as measures of symptom severity, respiratory function and inflammatory/immune pathways (C3/C-reactive protein) correlated with baseline Raman modes. Between visit spectral changes were highly significant (p = 0.0002) and were related to protein structure. Comparison of Raman data with established ALS biomarkers as a trial outcome measure demonstrated a reduction in required sample size with BSSMF Raman. Our portable, simple to use fibre optic system allied to BSSMF shows promise in the quantification of disease-related changes in ALS over short timescales.

Integrated evaluation of a panel of neurochemical biomarkers to optimize diagnosis and prognosis in amyotrophic lateral sclerosis

BACKGROUND AND PURPOSE

This study was undertaken to determine the diagnostic and prognostic value of a panel of serum biomarkers and to correlate their concentrations with several clinical parameters in a large cohort of patients with amyotrophic lateral sclerosis (ALS).

METHODS

One hundred forty-three consecutive patients with ALS and a control cohort consisting of 70 patients with other neurodegenerative disorders (DEG), 70 patients with ALS mimic disorders (ALSmd), and 45 healthy controls (HC) were included. Serum neurofilament light chain (NfL), ubiquitin carboxyl-terminal hydrolase isozyme L1 (UCHL1), glial fibrillary acidic protein (GFAP), and total tau protein levels were measured using ultrasensitive single molecule array.

RESULTS

NfL correlated with disease progression rate (p < 0.001) and with the measures of upper motor neuron burden (p < 0.001). NfL was higher in the ALS patients with classic and pyramidal phenotype. GFAP was raised in ALS with cognitive-behavioral impairment compared with ALS with normal cognition. NfL displayed the best diagnostic performance in discriminating ALS from HC (area under the curve [AUC] = 0.990), DEG (AUC = 0.946), and ALSmd (AUC = 0.850). UCHL1 performed well in distinguishing ALS from HC (AUC = 0.761), whereas it was not helpful in differentiating ALS from DEG and ALSmd. In multivariate analysis, NfL (p < 0.001) and UCHL1 (p = 0.038) were independent prognostic factors. Survival analysis combining NfL and UCHL1 effectively stratified patients with lower NfL levels (p < 0.001).

CONCLUSIONS

NfL is a useful biomarker for the diagnosis of ALS and the strongest predictor of survival. UCHL1 is an independent prognostic factor helpful in stratifying survival in patients with low NfL levels, likely to have slowly progressive disease. GFAP reflects extramotor involvement, namely cognitive impairment or frontotemporal dementia.

A phase I/IIa clinical trial of autologous hematopoietic stem cell transplantation in amyotrophic lateral sclerosis

OBJECTIVE

To verify the safety and potential effect on ALS progression of a low-intensity immunosuppressive regimen followed by autologous hematopoietic stem cell transplantation (aHSCT) in amyotrophic lateral sclerosis (ALS) patients.

METHODS

ALS eligible patients underwent a set of clinical and laboratory evaluations at T-4 (screening), T-1 (pre-treatment visit), and for the 12 consecutive months after treatment (T3, T6, T9, T12). We evaluated the tolerability of the procedure, its efficacy on clinical course and quality of life (QoL).

RESULTS

Eight of the 11 ALS patients enrolled received the established immunoablative protocol. The procedure was well tolerated and side effects were those expected. One patient died 4 months after the conditioning regimen and another patient underwent tracheotomy just before T3 for a sudden respiratory failure, but he is still alive 4 years after the procedure without being ventilated any more. A third patient died 10 months after conditioning. In the other cases, there was no statistical difference in all functional measures and QoL pre- and post-treatment; however, a transitory slopes' reduction of ALSFRS-R and seated SVC% after the conditioning procedures was reported. Moreover, although not statistically significant, trends of reduction of CD4 + and increment of CD8 + were found.

CONCLUSIONS

aHSCT was overall well tolerated, but it was not followed by any significant modification in disease progression. Considering the negative results of this small trial, further studies aimed to evaluate the possible efficacy of the aHSCT using a higher-intensity regimen should be carefully and with caution evaluated.

Association Between C-Reactive Protein and Risk of Amyotrophic Lateral Sclerosis: A Mendelian Randomization Study

Background: Until now, the relationship between C-reactive protein (CRP) levels and amyotrophic lateral sclerosis (ALS) risk has not been fully established. It is necessary to assess whether there is a causal relationship between C-reactive protein levels and ALS risk. Objective and Methods: We aimed to determine whether CRP has causal effects on risk of ALS. In this present study, summary-level data for ALS (20,806 cases and 59,804 controls) was obtained from large analyses of genome-wide association studies. For instrumental variables, 37 single nucleotide polymorphisms that had been previously identified to be related to CRP levels were used, including 4 SNPs of conservative CRP genetic variants and 33 SNPs of liberal CRP genetic variants. MR estimates were calculated using the inverse-variance weighted method, supplemented by MR-Egger, weighted median, and MR-PRESSO methods. Results: There was no significant causal relationship between genetically predicted CRP levels and ALS risk (OR = 1.123, 95% CI = 0.963-1.309, p = 0.139) and results for the conservative CRP instruments were consistent (OR = 0.964, 95% CI = 0.830-1.119, p = 0.628). Pleiotropic bias was not observed in this study. Conclusions: This study suggests that genetically predicted CRP levels may not be a causal risk factor for ALS.

C-reactive protein levels in patients with amyotrophic lateral sclerosis: A systematic review

INTRODUCTION

Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease affecting cortical and spinal motor neurons. There is a lack of optimal biomarkers to diagnose and prognosticate the ALS patients. C-reactive protein (CRP), an inflammatory marker, has shown promising results in ALS patients.

MATERIALS AND METHODS

PubMed, Embase, and Google Scholar databases were searched from 2000 to June 1, 2021 for suitable studies showing the relationship between CRP and ALS. The concentration of CRP levels was assessed between ALS patients and controls. Further, end outcomes like ALS functional rating scale (ALSFRS-R), survival status, and mortality risks were assessed in relation to CRP levels.

RESULTS

Eleven studies including five case-control, five cohorts, and one randomized control study were assessed. There were 2785 ALS patients and 3446 healthy controls. A significant increment in CRP levels among ALS patients in comparison with healthy controls were seen in most of the studies. ALSFRS-R and disease progression were found to be significantly correlated with CRP levels. Overall accuracy of CRP in CSF was 62% described in a single study.

CONCLUSION

Although CRP has shown promise as a prognostic biomarker, extensive cohort studies are required to assess its prognostic value and accuracy in diagnosing ALS taking into account the confounding factors.

Neutrophils-to-Lymphocyte Ratio Is Associated with Progression and Overall Survival in Amyotrophic Lateral Sclerosis

Background: Amyotrophic lateral sclerosis (ALS) is a devastating and untreatable motor neuron disease, with a 3–5-year survival from diagnosis. Possible prognostic serum biomarkers include albumin, C-reactive protein, ferritin, creatinine, uric acid, hemoglobin, potassium, sodium, calcium, glucose, and the neutrophil-to-lymphocyte ratio (NLR), a marker of subclinical inflammation. Objective: To ascertain the influence of NLR on ALS progression rate and survival. Methods: Cross-sectional multicenter study including 146 consecutive incident and prevalent patients (88 males), aged >18 years, diagnosed according to the El Escorial criteria. The exclusion criteria were: (1) patients with tracheostomy or receiving mechanical ventilation; (2) patients with percutaneous endoscopic gastrostomy; and (3) patients who did not sign the informed consent. The rate of disease progression (ΔFS score) represents the monthly decline of the ALSFRS-R score, and was computed as (48 − total ALSFRS-R at recruitment)/symptom duration in months. Patients were followed up to tracheotomy, death, or the end of the follow-up, whichever occurred first. To validate our findings, we used data retrieved from the Pooled Resource Open-Access ALS Clinical Trials (PRO-ACT) Database. Results: The median disease duration was 15 (range = 2–30) months. The mean ALSFRS-R score at recruitment was 35.8 ± 8.0 (range: 10–48), and the median ΔFS was 0.66 (range: 0–5.33). Age at onset, at diagnosis, and at recruitment were significantly lower in the lowest NLR tertile. NLR values positively correlated with ΔFS values (r = 0.28): the regression slope of NLR (log-values) was 0.60 (p < 0.001) before and 0.49 (p = 0.006) after adjustment for age at recruitment. The ΔFS score progressively increased from the lowest to the highest NLR tertile: 0.35 (IQR: 0.18–0.93), 0.62 (IQR: 0.25–1.09), and 0.86 (IQR: 0.53–1.92). Patients were followed for a median of 2 years. The mortality rate passed from 15.9 events per 100 person-years in patients belonging to the lowest NLR tertile to 52.8 in those in the highest tertile. The optimal cut-off value which best classified patients with the lowest and the highest mortality rate was set at the NLR value of 2.315. Indeed, the mortality rate of patients with an NLR value above such cut-off was twice the mortality rate of patients with a value below the cut-off (age adjusted hazard ratio (HR): 2.16, 95% confidence interval (CI): 1.32–3.53). In the PRO-ACT validation sample, patients with an NLR value above the cut-off consistently had a higher mortality rate than those with a value below the cut-off (age adjusted HR: 1.17, 95%CI: 1.01–1.35). Conclusions: NLR could be a candidate easy, fast, and low-cost marker of disease progression and survival in ALS. It may be associated with low-grade inflammation either as a direct mirror of the pathological process of disease progression, or as a consequence of neuronal death (reverse causation). However, prospective studies are needed to understand whether NLR changes during the course of the disease, before using it to monitor disease progression in ALS.

Phase 2B randomized controlled trial of NP001 in amyotrophic lateral sclerosis: pre‐specified and post‐hoc analyses

Introduction/Aims

ALS is a heterogeneous disease that may be complicated or in part driven by inflammation. NP001, a regulator of macrophage activation, was associated with slowing disease progression in those with higher levels of the plasma inflammatory marker C‐reactive protein (CRP) in phase 2A studies in ALS. Here, we evaluate the effects of NP001 in a phase 2B trial, and perform a post hoc analysis with combined data from the preceding phase 2A trial.

Methods

The phase 2B trial enrolled 138 participants within 3 y of symptom onset and with plasma hs‐CRP values >1.13 mg/L. They were randomized 1:1 to receive either placebo or NP001 for 6 mo. Change from baseline ALSFRS‐R scores was the primary efficacy endpoint. Secondary endpoints included vital capacity (VC) change from baseline and percentage of participants showing no decline of ALSFRS‐R score over 6 mo (non‐progressor).

Results

The phase 2B study did not show significant differences between placebo and active treatment with respect to change in ALSFRS‐R scores, or VC. The drug was safe and well tolerated. A post hoc analysis identified a 40‐ to 65‐y‐old subset in which NP001‐treated patients demonstrated slower declines in ALSFRS‐R score by 36% and VC loss by 51% compared with placebo. A greater number of non‐progressors were NP001‐treated compared with placebo (p = .004).

Discussion

Although the phase 2B trial failed to meet its primary endpoints, post hoc analyses identified a subgroup whose decline in ALSFRS‐R and VC scores were significantly slower than placebo. Further studies will be required to validate these findings.

Blood-based biomarkers of inflammation in amyotrophic lateral sclerosis

Amyotrophic Lateral Sclerosis (ALS) is a devastating neurodegenerative disease in which many processes are detected including (neuro)inflammation. Many drugs have been tested for ALS in clinical trials but most have failed to reach their primary endpoints. The development and inclusion of different types of biomarkers in diagnosis and clinical trials can assist in determining target engagement of a drug, in distinguishing between ALS and other diseases, and in predicting disease progression rate, drug responsiveness, or an adverse event. Ideally, among other characteristics, a biomarker in ALS correlates highly with a disease process in the central nervous system or with disease progression and is conveniently obtained in a peripheral tissue. Here, we describe the state of biomarkers of inflammation in ALS by focusing on peripherally detectable and cellular responses from blood cells, and provide new (combinatorial) directions for exploration that are now feasible due to technological advancements.

OUP accepted manuscript

The routine clinical integration of individualized objective markers of disease activity in those diagnosed with the neurodegenerative disorder amyotrophic lateral sclerosis is a key requirement for therapeutic development. A large, multicentre, clinic-based, longitudinal cohort was used to systematically appraise the leading candidate biofluid biomarkers in the stratification and potential therapeutic assessment of those with amyotrophic lateral sclerosis. Incident patients diagnosed with amyotrophic lateral sclerosis (n = 258), other neurological diseases (n = 80) and healthy control participants (n = 101), were recruited and followed at intervals of 3–6 months for up to 30 months. Cerebrospinal fluid neurofilament light chain and chitotriosidase 1 and blood neurofilament light chain, creatine kinase, ferritin, complement C3 and C4 and C-reactive protein were measured. Blood neurofilament light chain, creatine kinase, serum ferritin, C3 and cerebrospinal fluid neurofilament light chain and chitotriosidase 1 were all significantly elevated in amyotrophic lateral sclerosis patients. First-visit plasma neurofilament light chain level was additionally strongly associated with survival (hazard ratio for one standard deviation increase in log₁₀ plasma neurofilament light chain 2.99, 95% confidence interval 1.65–5.41, P = 0.016) and rate of disability progression, independent of other prognostic factors. A small increase in level was noted within the first 12 months after reported symptom onset (slope 0.031 log₁₀ units per month, 95% confidence interval 0.012–0.049, P = 0.006). Modelling the inclusion of plasma neurofilament light chain as a therapeutic trial outcome measure demonstrated that a significant reduction in sample size and earlier detection of disease-slowing is possible, compared with using the revised Amyotrophic Lateral Sclerosis Functional Rating Scale. This study provides strong evidence that blood neurofilament light chain levels outperform conventional measures of disease activity at the group level. The application of blood neurofilament light chain has the potential to radically reduce the duration and cost of therapeutic trials. It might also offer a first step towards the goal of more personalized objective disease activity monitoring for those living with amyotrophic lateral sclerosis.

Advancing mechanistic understanding and biomarker development in amyotrophic lateral sclerosis

INTRODUCTION

Proteomic analysis has contributed significantly to the study of the neurodegenerative disease amyotrophic lateral sclerosis (ALS). It has helped to define the pathological change common to nearly all cases, namely intracellular aggregates of phosphorylated TDP-43, shifting the focus of pathogenesis in ALS toward RNA biology. Proteomics has also uniquely underpinned the delineation of disease mechanisms in model systems and has been central to recent advances in human ALS biomarker development.

AREAS COVERED

The contribution of proteomics to understanding the cellular pathological changes, disease mechanisms, and biomarker development in ALS are covered.

EXPERT OPINION

Proteomics has delivered unique insights into the pathogenesis of ALS and advanced the goal of objective measurements of disease activity to improve therapeutic trials. Further developments in sensitivity and quantification are expected, with application to the presymptomatic phase of human disease offering the hope of prevention strategies.

Neutrophil-to-lymphocyte ratio in sporadic amyotrophic lateral sclerosis

The neutrophil-to-lymphocyte ratio (NLR) is considered a robust prognostic biomarker for predicting patient survival outcomes in many diseases. However, it remains unclear whether it can be used as a biomarker for amyotrophic lateral sclerosis (ALS). To correlate NLR with disease progression and survival in sporadic ALS, 1030 patients with ALS between January 2012 and December 2018 were included in this study. These patients were assigned into three groups according to their NLR values: Group 1 (NLR < 2, n = 544 [52.8%]), Group 2 (NLR = 2-3, n = 314 [30.5%]), and Group 3 (NLR > 3, n = 172 [16.7%]). All patients were followed up until April 2020. Patients in Group 3 had a significantly older onset age, a lower score on the Revised ALS Functional Rating Scale, and rapidly progressing disease conditions. Furthermore, faster disease progression rates were associated with higher NLR values (odds ratio = 1.211, 95% confidence interval [CI]: 1.090-1.346, P < 0.001) after adjusting for other risk factors. Compared with Groups 1 and 2, the survival time in Group 3 was significantly shorter (log-rank P = 0.002). The NLR value was considered an independent parameter for the prediction of survival in ALS patients after normalizing for all other potential parameters (hazard ratio [HR] = 1.079, 95% CI: 1.016-1.146, P = 0.014). The effects on ALS survival remained significant when adjusted for treatment (HR = 1.074, 95% CI: 1.012-1.141, P_trend = 0.019) or when considering the stratified NLR value (HR = 1.115, 95% CI: 1.009-1.232, P_trend = 0.033). Thus, the NLR may help to predict the rate of disease progression and survival in patients with sporadic ALS. The study was approved by the Institutional Ethics Committee of West China Hospital of Sichuan University, China (approval No. 2015 (236)) on December 23, 2015.