Clinical disease stage related changes of serological factors in amyotrophic lateral sclerosis

Role of uric acid in neurodegenerative diseases, focusing on Alzheimer and Parkinson disease: A new perspective

Neurodegenerative diseases (NDs) such as Alzheimer disease (AD) and Parkinson disease (PD) are group of diseases affecting the central nervous system (CNS) characterized by progressive neurodegenerations and cognitive impairment. Findings from different studies highlighted the beneficial and detrimental effects of serum uric acid on the development and progression of NDs. Therefore, this mini-review aims to discuss the beneficial and detrimental effects of uric on NDs. The neuroprotective effect of uric acid is mainly related to the antioxidant effect of uric acid which alleviates oxidative stress-induced neurodegeneration in AD and PD. However, long-term effect of hyperuricemia prompts for the development and progression of cognitive impairment. Hyperuricemia is associated with cognitive impairment and dementia, and gout increases dementia risk. In addition, hyperuricemia can cause cerebral vascular injury which is a risk factor for vascular dementia and cognitive impairment. Taken together, the relationship between uric acid and NDs risk remains conflicting. Hence, preclinical and clinical studies are indicated in this regard.

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.

The Impact of Serum Uric Acid on the Progression of Amyotrophic Lateral Sclerosis in Adults Aged 18 and Older: A Systematic Review

We have conducted this review to see if serum uric acid (UA) is associated with slowing amyotrophic lateral sclerosis (ALS) progression in adult patients who are at least 18 years old. Understanding the effects of this biomarker for future use is critical because of its easy accessibility. This systematic review paper examined five previous years of recent studies and reports, published in English and limited to human investigations from the Cochrane, PubMed, and Google Scholar databases. Using instruments for assessing the eligibility and quality of systematic and narrative reviews, we narrowed our search to 11 reports that show evidence of a positive association between high blood uric acid and the progression of ALS. However, this claim still needs confirmation by future studies to confirm that possibility. The results of this systematic review may provide a strong foundation for future studies on this biomarker, demonstrating the significance of blood uric acid levels in ALS and highlighting the necessity of using that biomarker to track the disease's progression.

Serum uric acid level predicts the progression of amyotrophic lateral sclerosis following treatment with edaravone

Introduction

Uric acid and edaravone might exert a neuroprotective effect in amyotrophic lateral sclerosis (ALS) by reducing oxidative stress. We analyzed whether the treatment effect of edaravone is pronounced in patients whose uric acid level increased after the treatment with edaravone.

Materials and methods

Forty patients with ALS who underwent treatment with edaravone were included. Baseline uric acid level and the rate of decline in uric acid after edaravone treatment were recorded. The rate of change of ALS functional rating scale-revised (ΔALSFRS-R/month) was calculated based on baseline ALSFRS-R score and ALSFRS-R score 6–24 weeks after the treatment.

Results

The serum uric acid levels decreased after treatment in 26 (65%) patients and increased in 12 (30%) patients. The ΔALSFRS-R/month was significantly faster in patients whose uric acid decreased (median 1.5 [Q1–Q3, 0.7–3.1]) than in patients whose uric acid increased (0.2 [0–1.0], p = 0.021). A high baseline uric acid level and low rate of decline in uric acid was associated with slower disease progression after adjusting for age, initial symptoms, and riluzole administration (p = 0.030 and p = 0.041, respectively).

Discussion

High baseline values and low rate of decline in uric acid may predict slow disease progression in ALS patients treated with edaravone.

Unraveling the complex interplay between genes, environment, and climate in ALS

Various genetic and environmental risk factors have been implicated in the pathogenesis of amyotrophic lateral sclerosis (ALS). Despite this, the cause of most ALS cases remains obscure. In this review, we describe the current evidence implicating genetic and environmental factors in motor neuron degeneration. While the risk exerted by many environmental factors may appear small, their effect could be magnified by the presence of a genetic predisposition. We postulate that gene-environment interactions account for at least a portion of the unknown etiology in ALS. Climate underlies multiple environmental factors, some of which have been implied in ALS etiology, and the impact of global temperature increase on the gene-environment interactions should be carefully monitored. We describe the main concepts underlying such interactions. Although a lack of large cohorts with detailed genetic and environmental information hampers the search for gene-environment interactions, newer algorithms and machine learning approaches offer an opportunity to break this stalemate. Understanding how genetic and environmental factors interact to cause ALS may ultimately pave the way towards precision medicine becoming an integral part of ALS care.

Plasma Uric Acid Helps Predict Cognitive Impairment in Patients With Amyotrophic Lateral Sclerosis

Objective: Uric acid as an antioxidant plays an important role in neurodegenerative disease. Our objective is to investigate the relationship between plasma uric acid and cognitive impairment in patients with amyotrophic lateral sclerosis (ALS).

Methods: In this cross-sectional study, 124 ALS patients were screened by the Edinburgh Cognitive and Behavioral Screen (ECAS) and classified according to the revised Strong's criteria. Additionally, based on total ECAS cut-off score patients were categorized into those with cognitive impairment (ALS-cie) and those without cognitive impairment (ALS-ncie), and clinical data and uric acid level were compared between the two groups. Parameters with significant differences were further included in a multivariate linear regression analysis with ECAS score as a dependent variable. Hold-out validation was performed to evaluate the fitness of regression model.

Results: Up to 60% of ALS patients showed cognitive or/and behavioral impairment. The ALS-cie group had lower education level (p < 0.001), older age at symptom onset (p = 0.001), older age at testing (p = 0.001), and lower plasma uric acid (p = 0.01). Multivariate analysis showed increased uric acid (β = 0.214, p = 0.01), lower age at testing (β = −0.378, p < 0.001), and higher education level (β = 0.424, p < 0.001) could predict higher ECAS score (F = 19.104, R² = 0.381, p < 0.0001). Validation analysis showed that predicted ECAS score was significantly correlated with raw ECAS score in both the training set (rs = 0.621, p < 0.001) and the testing set (rs = 0.666, p < 0.001).

Conclusions: Cognitive impairment was a common feature in our Chinese ALS patients. Plasma uric acid might help evaluate the risk of cognitive impairment in ALS patients when combined with education level and age at testing.

Milano-Torino Staging and Long-Term Survival in Chinese Patients with Amyotrophic Lateral Sclerosis

(1) Background: The aim of this longitudinal study was to evaluate the association between disease progression according to the Milano–Torino staging (MITOS) system and long-term survival in Chinese patients with amyotrophic lateral sclerosis (ALS). We also examined factors affecting MITOS progression. (2) Methods: Patients were enrolled and underwent follow-up at 6, 12, 18, and 24 months, and their demographic and clinical data, including the Milano–Torino stage, Amyotrophic Lateral Sclerosis Functional Rating Scale—Revised (ALSFRS-R) score and neuropsychiatric data, were evaluated. The sensitivity and specificity of predicting survival outcomes based on MITOS progression and ALSFRS-R score decline from baseline to 6 months were compared. The associations between MITOS progression from baseline to 6 months and survival outcome at 12, 18 and 24 months were examined, and factors associated with disease progression were evaluated with subgroup analyses. (3) Results: Among the 100 patients included, 74% were in stage 0 at baseline, and approximately 95% progressed to a higher stage of the MITOS system at 24 months. MITOS progression from baseline to 6 months and ALSFRS-R decline showed comparable value for predicting survival at 12, 18, and 24 months. MITOS progression from baseline to 6 months is strongly associated with death outcomes. Older age at onset and increased depression and anxiety scores may be related to disease progression. (4) Conclusions: MITOS progression during the early disease course could serve as a prognostic marker of long-term survival and may have utility in clinical trials. Age at onset and diagnosis and neuropsychiatric factors might be associated with disease progression.

Downregulating carnitine palmitoyl transferase 1 affects disease progression in the SOD1 G93A mouse model of ALS

Amyotrophic lateral sclerosis (ALS) is a fatal motor neuron disease characterized by death of motor neurons. The etiology and pathogenesis remains elusive despite decades of intensive research. Herein, we report that dysregulated metabolism plays a central role in the SOD1 G93A mouse model mimicking ALS. Specifically, we report that the activity of carnitine palmitoyl transferase 1 (CPT1) lipid metabolism is associated with disease progression. Downregulation of CPT1 activity by pharmacological and genetic methods results in amelioration of disease symptoms, inflammation, oxidative stress and mitochondrial function, whereas upregulation by high-fat diet or corticosterone results in a more aggressive disease progression. Finally, we show that downregulating CPT1 shifts the gut microbiota communities towards a protective phenotype in SOD1 G93A mice. These findings reveal that metabolism, and specifically CPT1 lipid metabolism plays a central role in the SOD1 G93A mouse model and shows that CPT1 might be a therapeutic target in ALS.

Intuitive Staging Correlates With King's Clinical Stage

Background: Clinical stage in amyotrophic lateral sclerosis (ALS) can be assigned using King's staging with a simple protocol based on the number of CNS regions involved and the presence of significant nutritional or respiratory failure. It is important that the assigned clinical stage matches expectations, and generally corresponds with how a health care professional would intuitively stage the patient. We therefore investigated the relationship between King's clinical ALS stage and ALS stage as intuitively assigned by health care professionals. Methods: We wrote 17 case vignettes describing people with ALS at different disease stages from very early limited disease involvement through to severe, multi-domain disease. During two workshops, we asked health care professionals to intuitively stage the vignettes and compared the answers with the actual King's clinical ALS stage. Results: There was a good correlation between King's clinical ALS stage and intuitively assigned stage, with a Spearman's Rank correlation coefficient of 0.64 (p < 0.001). There was no difference in the intuitive stages assigned by practitioners of different types or at different levels of experience. Conclusions: Across a spectrum of ALS scenarios, King's clinical ALS stage corresponds to intuitive ALS stage as assigned by a range of health care professionals.

Serum Uric Acid Levels Predict Mortality Risk in Male Amyotrophic Lateral Sclerosis Patients

Objective: To explore the associations between serum uric acid levels with survival in male and female ALS patients. Methods: A longitudinal cohort study was carried out including 313 sporadic and 16 familial ALS patients with repeated serum uric acid measurements. Multivariate Cox regression models were used to evaluate the survival-related factors. Results: There were 207 male and 122 female, and the mean age of onset was 55.7 ± 11.2 years old. The male patients had significantly higher baseline uric acid levels than that in female patients (342.4 ± 91.4 vs. 279.3 ± 71.4 μmol/L; p < 0.0001). The uric acid levels were inversely associated with the decline rate of ALSFRS-R per month (ΔALSFRS-R). After multivariate Cox regression analysis, a survival advantage was found in male, but not female, with higher serum uric acid levels. In males, a shorter diagnostic delay (≤10 m), lower BMI at baseline (≤18.70 kg/m²), faster disease progression (ΔALSFRS-R > 0.63), and lower baseline uric acid levels (≤292 μmol/L, HR: 1.936; 95% CI: 1.334-2.810) were associated with a shorter survival. During follow-up, the serum uric acid levels were not significantly altered over time. Conclusion: There is an inverse correlation between baseline serum uric acid levels and risk of death, prominently in male ALS patients.

Serum Creatinine Protects Against Amyotrophic Lateral Sclerosis: a Mendelian Randomization Study

Association between serum creatinine (sCr) and amyotrophic lateral sclerosis (ALS) has been reported in previous observational studies, but results are at risk of confounding bias and reverse causation. Therefore, whether such association is casual remains unclear. Herein, we performed a two-sample Mendelian randomization study to evaluate the causal relationship between sCr and ALS in both European and East Asian populations. Our analysis was conducted using summary statistics from genome-wide association studies with 358,072 individuals for sCr and 80,610 individuals for ALS in European population, and 142,097 individuals for sCr and 4,084 individuals for ALS in East Asian population. The inverse-variance weighted method was used to estimate the casual-effect of sCr on ALS in both populations, and other MR methods were also performed as sensitivity analyses. We found evidence that genetically predicted sCr was inversely associated with risk of ALS (OR, 0.92; 95% CI, 0.85-0.99; P = 0.028) in European population. However, there was no strong evidence for a causal relationship between sCr and ALS in East Asian population (OR, 0.92; 95% CI, 0.84-1.01; P = 0.084). This study provides evidence that sCr protects against ALS in European population but not in East Asian population.

Aberrations of biochemical indicators in amyotrophic lateral sclerosis: a systematic review and meta-analysis

Accumulating evidence has suggested that the pathological changes in amyotrophic lateral sclerosis (ALS) are not only confined to the central nervous system but also occur in the peripheral circulating system. Here, we performed a meta-analysis based on the PubMed, EMBASE, EBSCO, and CNKI databases, to find out biochemical indicators associated with energy metabolism, iron homeostasis, and muscle injury that are altered in ALS patients and their correlations with ALS phenotypes. Forty-six studies covering 17 biochemical indicators, representing 5454 ALS patients and 7986 control subjects, were included in this meta-analysis. Four indicators, including fasting blood glucose level (weighted mean difference [WMD] = 0.13, 95% CI [0.06–0.21], p = 0.001), serum ferritin level (WMD = 63.42, 95% CI [48.12–78.73], p < 0.001), transferrin saturation coefficient level (WMD = 2.79, 95% CI [1.52–4.05], p < 0.001), and creatine kinase level (WMD = 80.29, 95% CI [32.90–127.67], p < 0.001), were significantly higher in the ALS patients, whereas the total iron-binding capacity (WMD = − 2.42, 95% CI [− 3.93, − 0.90], p = 0.002) was significantly lower in ALS patients than in the control subjects. In contrast, the other 12 candidates did not show significant differences between ALS patients and controls. Moreover, pooled hazard ratios (HR) showed significantly reduced survival (HR = 1.38, 95% CI [1.02–1.88], p = 0.039) of ALS patients with elevated serum ferritin levels. These findings suggest that abnormalities in energy metabolism and disruption of iron homeostasis are involved in the pathogenesis of ALS. In addition, the serum ferritin level is negatively associated with the overall survival of ALS patients.

Creatine kinase in the diagnosis and prognostic prediction of amyotrophic lateral sclerosis: a retrospective case-control study

Creatine kinase is a muscle enzyme that has been reported at various levels in different studies involving patients with amyotrophic lateral sclerosis. In the present retrospective case-control study, we included 582 patients with amyotrophic lateral sclerosis and 582 age- and sex-matched healthy controls. All amyotrophic lateral sclerosis participants received treatment in the Department of Neurology, West China Hospital, China, between May 2008 and December 2018. Serum creatine kinase levels in patients with amyotrophic lateral sclerosis were significantly higher than those in healthy controls. Subgroup analysis revealed that serum creatine kinase levels in men were higher than those in women in both amyotrophic lateral sclerosis patients and healthy controls. Compared with patients with bulbar-onset amyotrophic lateral sclerosis, patients with limb-onset amyotrophic lateral sclerosis had higher creatine kinase levels. Spearman's correlation analysis revealed that serum creatine kinase levels were not correlated with body mass index, Amyotrophic Lateral Sclerosis Functional Rating Scale-Revised score, or progression rate. After adjusting for prognostic covariates, higher log creatine kinase values were correlated with higher overall survival in the amyotrophic lateral sclerosis patients. We also investigated the longitudinal changes in serum creatine kinase levels in 81 amyotrophic lateral sclerosis patients; serum creatine kinase levels were decreased at the second blood test, which was sampled at least 6 months after the first blood test. Together, our results suggest that serum creatine kinase levels can be used as an independent factor for predicting the prognosis of amyotrophic lateral sclerosis patients. This study received ethical approval from the Ethics Committee of West China Hospital, China (approval No. 2015(236)) on December 23, 2015.

Correlational Analysis of ALS Progression and Serum NfL Measured by Simoa Assay in Chinese Patients

Background: Neurofilament light chain (NFL) was believed to be a promising biomarker for the diagnosis of Amyotrophic lateral sclerosis (ALS) and disease burden evaluation.

Objective: To determine the serum NFL level and its clinical relevance, including its association with disease severity [evaluated by the ALS Functional Rating Scale–revised (ALSFRS-r) score and King's College staging system] and progression (evaluated by the disease progression rate (DPR) and diagnostic delay), in ALS patients in China.

Method: Serum NFL levels were detected using the Single Molecule Array (Simoa) technology in 30 ALS patients and 20 healthy controls (HCs).

Results: There were significantly elevated levels of serum NFL in patients with ALS than in the HCs (P < 0.001). The serum NFL levels were significantly higher in rapidly progressive ALS and patients in Stage 3 than in slowly progressive ALS and patients in Stage 2 (P_DPR < 0.001, P_{Diagnosticdelay} = 0.019; P_stage= 0.033). Furthermore, the serum NFL levels negatively correlated with the diagnostic delay (R² = 0.23, P = 0.016), the ALSFRS-r score (R² = 0.15, P = 0.047) and disease duration (R² = 0.15, P = 0.034), and positively correlated with the DPR (R² = 0.42, P < 0.001).

Conclusions: The present study preliminarily investigated the diagnostic value of serum NFL and its clinical relevance in the Chinese ALS population using the ultrasensitive Simoa technology. The results demonstrated that the level of serum NFL may become a potential biomarker for ALS diagnosis and indicate disease severity and progression.

Lipid Profile in Patients With Amyotrophic Lateral Sclerosis: A Systematic Review and Meta-Analysis

Background: Studies have investigated the lipid profile in amyotrophic lateral sclerosis (ALS), including the levels of total cholesterol (TC), triglyceride (TG), high-density lipoprotein (HDL), and higher low-density lipoprotein (LDL), and the associations with mortality of ALS, but the results were inconsistent. Therefore, we conducted this meta-analysis to systematically answer this unsolved question.

Methods: We searched all the related studies that probed into the association between serum lipid levels and ALS based on PubMed, EMBASE, and Cochrane library from January 1990 to July 2020. The quality of the included studies was evaluated by using the Newcastle–Ottawa Scale (NOS). All the statistical analyses of this meta-analysis were performed using the Stata version 12.0 software.

Results: Fourteen studies with a total of 3,291 ALS patients and 3,367 controls were included. Among them, 10 studies compared the lipid profile between ALS patients and controls. The results indicated that compared with controls, ALS patients from both Europe and Asia had lower levels of TG and HDL, but the levels of TC and LDL were higher in ALS patients from Europe. However, after systemic analyses, the altered TC level was significant only in Asian ALS patients; the differences of other lipids were not significant. Concerning the effect of lipid profile on mortality of ALS, analyses of four cohort studies showed that the levels of all lipids were not associated with overall mortality in ALS.

Conclusion: The results of the present study showed that Asian ALS patients had lower TC levels than controls, and the levels of all lipids were not associated with mortality of ALS.

Serum creatinine levels in patients with amyotrophic lateral sclerosis: a systematic review and meta-analysis

BACKGROUND

Serum creatinine (Cr) is a biosynthetic product of creatine phosphate metabolism in muscles and is closely related to total muscle mass, but it is not easily affected by diet. Several studies have tried to explore the role of serum Cr levels in amyotrophic lateral sclerosis (ALS), but the results were inconsistent. Therefore, our study aims to explore the differences of serum Cr levels between ALS patients and controls and whether serum Cr at baseline is an independent predictor of survival. Methods: We searched all the related studies that probed into the association between Serum Cr levels and ALS based on PubMed, EMBASE and Cochrane library from October 1952 to February 2019. The quality of the included studies was evaluated by using Newcastle-Ottawa Scale (NOS), and all the statistical analysis of this meta-analysis was performed by Stata version 12.0. Results: Eight studies with a total of 11377 ALS patients and 937 controls were included. Among them, five studies indicated that ALS patients had lower serum Cr levels (SMD = -0.78, 95%CI [-0.97, -0.60]) compared to controls, and three studies showed that higher serum Cr levels in ALS patients were related to lower overall mortality (HR 0.89, 95%CI [0.80, 0.99]). Conclusion: The levels of serum Cr in ALS patients are significantly lower than those in controls, and they are inversely related to overall mortality in ALS patients. Therefore, the serum Cr, an easily accessible serological factor, may serve as a prognostic biomarker.