Association Between Dietary Intake and Function in Amyotrophic Lateral Sclerosis

Amyotrophic lateral sclerosis (ALS), cancer, autoimmunity and metabolic disorders: An unsolved tantalizing challenge

Amyotrophic lateral sclerosis (ALS) commonly referred to as motor neurone disease, is a neurodegenerative disease of unknown pathogenesis that progresses rapidly and has attracted an increased amount of scholarly interest in recent years. The current conception of amyotrophic lateral sclerosis has transitioned into a more complex theory in which individual genetic risk, ageing and environmental factors interact, leading to disease onset in subjects in whom the sum of these factors reach a determined threshold. Based on this conceptualization, the environmental conditions, particularly those that are potentially modifiable, are becoming increasingly relevant. In this review, the current integrative model of the disease is discussed. In addition, we explore the role of cancer, autoimmunity and metabolic diseases as examples of novel, non-genetic and environmental factors. Together with the potential triggers or perpetuating pathogenic mechanisms along with new insights into potential lines of future research are provided. LINKED ARTICLES: This article is part of a themed issue on Neurochemistry in Japan. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v178.6/issuetoc.

Association Between Vitamins and Amyotrophic Lateral Sclerosis: A Center-Based Survey in Mainland China

To date, conflicting results about the role of vitamins in amyotrophic lateral sclerosis (ALS) have been reported along with a lack of systematic studies on all types of serum vitamins in patients with ALS. Moreover, extensive studies have been conducted on vitamins in other neurodegenerative diseases; however, whether serum vitamin alterations in ALS are similar to those in other neurodegenerative diseases remains unclear. Therefore, we performed a study involving a large Chinese cohort of patients with ALS to address this gap. In this study, 202 patients with ALS, 214 with a neurodegenerative disease that mimicked ALS (mimics), and 208 healthy controls were enrolled. Serum vitamins of all subjects were examined under fasting state in Clinical Laboratory. As a result, we found that higher vitamin A and E levels and lower vitamin B2, B9, and C levels were in patients with ALS compared to healthy controls, and that high vitamin A and E levels, and low vitamin B2, B9, and C levels were associated with an increased risk for ALS. In addition, serum vitamin C was lower in early-onset ALS patients compared to those in late-onset ALS patients; however, there was no significant correlation between serum vitamins and age at onset, sites at onset, disease duration, or disease severity of ALS. We also found that patients with ALS showed similar vitamin alterations to mimics, with the exception of vitamin E. In summary, our study adds information to the literature on the role of vitamins in ALS and provides support for clinical guidance regarding dietary changes and vitamin supplements in patients with ALS.

From basic research to the clinic: innovative therapies for ALS and FTD in the pipeline

Amyotrophic lateral sclerosis (ALS) and Frontotemporal Degeneration (FTD) are neurodegenerative disorders, related by deterioration of motor and cognitive functions and short survival. Aside from cases with an inherited pathogenic mutation, the causes of the disorders are still largely unknown and no effective treatment currently exists. It has been shown that FTD may coexist with ALS and this overlap occurs at clinical, genetic, and molecular levels. In this work, we review the main pathological aspects of these complex diseases and discuss how the integration of the novel pathogenic molecular insights and the analysis of molecular interaction networks among all the genetic players represents a critical step to shed light on discovering novel therapeutic strategies and possibly tailoring personalized medicine approaches to specific ALS and FTD patients.

Potential Preventive Strategies for Amyotrophic Lateral Sclerosis

It may seem useless to propose preventive measures for a disease without established pathogenesis and successful therapy, such as amyotrophic lateral sclerosis (ALS). However, we will show that ALS shares essential molecular mechanisms with aging and that established anti-aging strategies, such as healthy diet or individually adjusted exercise, may be successfully applied to ameliorate the condition of ALS patients. These strategies might be applied for prevention if persons at ALS risk could be identified early enough. Recent research advances indicate that this may happen soon.

Plasma creatinine and oxidative stress biomarkers in amyotrophic lateral sclerosis

Objective: To determine the associations between plasma creatinine (PCr), plasma uric acid (PUA), and urinary oxidative stress (OS) biomarkers with the ALSFRS-R at baseline and survival in a large epidemiological cohort study (ALS COSMOS) with a well-phenotyped patient population (N = 355).Methods: Fasting plasma and first void urine samples were obtained. PCr, PUA, urinary 8-oxo-deoxy guanosine (8-oxodG), and 15-F_2t-isoprostane (IsoP) were analyzed at baseline, near the midpoint of follow-up, and at the final blood draw (before death or withdrawal from study). We estimated associations between these biomarkers and the ALSFRS-R at baseline and survival.Results: At baseline, PCr correlated with ALSFRS-R (Spearman r = 0.30), percent (%) FVC (r = 0.20), PUA (r = 0.37), and 8-oxodG (r = -0.13, all p < 0.05). Baseline PCr significantly predicted survival (adjusted hazard ratio 0.28, p < 0.001). Time to death from baseline was shortest for those in the lowest two PCr quartiles relative to the highest two quartiles. PCr and ALSFRS-R values were significantly correlated at all three time points (baseline: r = 0.29, midpoint: r = 0.23, final: r = 0.38, all p < 0.001). PCr and PUA significantly declined over time, whereas OS biomarkers significantly increased over time.Conclusions: To date, PCr predicted survival the best, compared to PUA, 8-oxodG, and IsoP. Although PCr represents the degree of muscle mass, it may also represent complex biochemical changes in ALS. Because the field has no reliable prognostic biomarkers, the importance of PCr warrants further investigation through clinical studies in ALS.

A Quantile-Based g-Computation Approach to Addressing the Effects of Exposure Mixtures

BACKGROUND

Exposure mixtures frequently occur in data across many domains, particularly in the fields of environmental and nutritional epidemiology. Various strategies have arisen to answer questions about exposure mixtures, including methods such as weighted quantile sum (WQS) regression that estimate a joint effect of the mixture components.

OBJECTIVES

We demonstrate a new approach to estimating the joint effects of a mixture: quantile g-computation. This approach combines the inferential simplicity of WQS regression with the flexibility of g-computation, a method of causal effect estimation. We use simulations to examine whether quantile g-computation and WQS regression can accurately and precisely estimate the effects of mixtures in a variety of common scenarios.

METHODS

We examine the bias, confidence interval (CI) coverage, and bias-variance tradeoff of quantile g-computation and WQS regression and how these quantities are impacted by the presence of noncausal exposures, exposure correlation, unmeasured confounding, and nonlinearity of exposure effects.

RESULTS

Quantile g-computation, unlike WQS regression, allows inference on mixture effects that is unbiased with appropriate CI coverage at sample sizes typically encountered in epidemiologic studies and when the assumptions of WQS regression are not met. Further, WQS regression can magnify bias from unmeasured confounding that might occur if important components of the mixture are omitted from the analysis.

DISCUSSION

Unlike inferential approaches that examine the effects of individual exposures while holding other exposures constant, methods like quantile g-computation that can estimate the effect of a mixture are essential for understanding the effects of potential public health actions that act on exposure sources. Our approach may serve to help bridge gaps between epidemiologic analysis and interventions such as regulations on industrial emissions or mining processes, dietary changes, or consumer behavioral changes that act on multiple exposures simultaneously. https://doi.org/10.1289/EHP5838.

The effects of diet and sex in amyotrophic lateral sclerosis

Amyotrophic lateral sclerosis (ALS) is a devastating neurodegenerative disease with no known cure. Approximately 90% of ALS cases are sporadic, suggesting there are multiple contributing factors that influence the disease risk, onset, and progression. Diet and sex are two factors that have been reported to alter ALS risk, onset and progression in humans and in animal models, providing potential modifiers of disease. Several epidemiological studies have identified diets that positively affect ALS patients, including various high-calorie fat or sugar-based diets, while animal models have been developed to test how these diets are working on a molecular level. These diets may offset the metabolic alterations that occur in ALS, such as hypermetabolism, lowered body mass index(BMI), and hyperlipidemia. Sex-dependent differences have also come forth from large-scale epidemiological studies as well as mouse-model studies. In addition, sex hormones have been shown to affect disease risk or progression. Herein, studies on the effects of diet and sex on ALS risk, onset, and progression will be reviewed. Understanding these diet- and sex-dependent outcomes may lead to optimized patient-specific therapies for ALS.

Antioxidant Alternatives in the Treatment of Amyotrophic Lateral Sclerosis: A Comprehensive Review

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease that produces a selective loss of the motor neurons of the spinal cord, brain stem and motor cortex. Oxidative stress (OS) associated with mitochondrial dysfunction and the deterioration of the electron transport chain has been shown to be a factor that contributes to neurodegeneration and plays a potential role in the pathogenesis of ALS. The regions of the central nervous system affected have high levels of reactive oxygen species (ROS) and reduced antioxidant defenses. Scientific studies propose treatment with antioxidants to combat the characteristic OS and the regeneration of nicotinamide adenine dinucleotide (NAD+) levels by the use of precursors. This review examines the possible roles of nicotinamide riboside and pterostilbene as therapeutic strategies in ALS.

Metabolic Alteration and Amyotrophic Lateral Sclerosis Outcome: A Systematic Review

Background: The development of strategies that could not only efficiently detect the onset of Amyotrophic Lateral Sclerosis (ALS), a fatal neurodegenerative disorder with no cure but also predict its development and evaluate therapeutic intervention would be of great value. In this respect, the metabolic status of ALS patients has called attention. Hence, this study aimed to investigate the potential correlation between changes in ALS's metabolic parameters with the disease outcome in a systematic review. Methods: The manuscripts were manually searched within different databases (PubMed, Web of Science and Cochrane). The inclusion criteria were original articles and reviews about individuals with ALS and its survival, disease prognosis and metabolism (weight, cholesterol, hypertension, BMI, and glycaemia). The authors also established three different exclusion criteria: studies including ALS and other degenerative disorders, works including animal models and published before the year 2000. Results: In total, 29 papers were selected. From all manuscripts, only 82.8% ensured the participation of sALS patients. Also, 27.6% of selected studies described the presence of a genetic mutation. Regarding ALS prognosis, patient's age, the age of ALS onset, ALS duration and survival, <50% of the papers addressed these issues. Specifically, regarding metabolism, 65.5% of articles mentioned BMI, 20.7% mentioned any data concerning hypertension, 6.89% cardiovascular risk, 10.3% obesity, 13.78% diabetes and 10.3% glycaemia. Concerning lipid metabolism, more results were gathered, but still, they did not suffice to establish a correlation with ALS development. Conclusions: Altogether, the authors concluded that available information is not enough to establish a link between ALS and metabolism. In reality, less than half of the manuscripts evaluated show an association between both factors. Nonetheless, it is worth mentioning that metabolism does influence ALS, but not in a unique manner. There is a debate about patients' hypo- and hypermetabolism. Thus, to provide a reliable record, a public policy in which all research and clinical centers might assess the parameters discussed herein is suggested. Accordingly, this systematic review attempts to provide a comprehensible database to facilitate multicentered collaboration, validation, and clinical translation.

Effect of nutrition on neurodegenerative diseases. A systematic review

Neurodegenerative diseases are characterized by the progressive functional loss of neurons in the brain, causing cognitive impairment and motoneuron disability. Although multifactorial interactions are evident, nutrition plays an essential role in the pathogenesis and evolution of these diseases. A systematic literature search was performed, and the prevalence of studies evaluated the effect of the Mediterranean diet (MeDiet), nutritional support, EPA and DHA, and vitamins on memory and cognition impairment. The data showed that malnutrition and low body mass index (BMI) is correlated with the higher development of dementia and mortality. MeDiet, nutritional support, and calorie-controlled diets play a protective effect against cognitive decline, Alzheimer's disease (AD), Parkinson disease (PD) while malnutrition and insulin resistance represent significant risk factors. Malnutrition activates also the gut-microbiota-brain axis dysfunction that exacerbate neurogenerative process. Omega-3 and -6, and the vitamins supplementation seem to be less effective in protecting neuron degeneration. Insulin activity is a prevalent factor contributing to brain health while malnutrition correlated with the higher development of dementia and mortality.

The Cumulative Risk of Chemical and Nonchemical Exposures on Birth Outcomes in Healthy Women: The Fetal Growth Study

Metals, stress, and sociodemographics are commonly studied separately for their effects on birth outcomes, yet often jointly contribute to adverse outcomes. This study analyzes two methods for measuring cumulative risk to understand how maternal chemical and nonchemical stressors may contribute to small for gestational age (SGA). SGA was calculated using sex-specific fetal growth curves for infants of pregnant mothers (n = 2562) enrolled in the National Institute of Child Health and Human Development (NICHD) Fetal Growth Study. The exposures (maternal lead, mercury, cadmium, Cohen's perceived stress, Edinburgh depression scores, race/ethnicity, income, and education) were grouped into three domains: metals, psychosocial stress, and sociodemographics. In Method 1 we created cumulative risk scores using tertiles. Method 2 employed weighted quantile sum (WQS) regression. For each method, logistic models were built with three exposure domains individually and race/ethnicity, adjusting for age, parity, pregnancy weight gain, and marital status. The adjusted effect of overall cumulative risk with three domains, was also modeled using each method. Sociodemographics was the only exposure associated with SGA in unadjusted models ((odds ratio) OR: 1.35, 95% (confidence interval) CI: 1.08, 1.68). The three cumulative variables in adjusted models were not significant individually, but the overall index was associated with SGA (OR: 1.17, 95% CI: 1.02, 1.35). In the WQS model, only the sociodemographics domain was significantly associated with SGA. Sociodemographics tended to be the strongest risk factor for SGA in both risk score and WQS models.

Gut microbiota in ALS: possible role in pathogenesis?

Introduction: The gut microbiota has important roles in maintaining human health. The microbiota and its metabolic byproducts could play a role in the pathogenesis of neurodegenerative diseases, including amyotrophic lateral sclerosis (ALS). Areas covered: The authors evaluate the methods of assessing the gut microbiota, and also review how the gut microbiota affects the various physiological functions of the gut. The authors then consider how gut dysbiosis could theoretically affect the pathogenesis of ALS. They present the current evidence regarding the composition of the gut microbiota in ALS and in rodent models of ALS. Finally, the authors review therapies that could improve gut dysbiosis in the context of ALS. Expert opinion: Currently reported studies suggest some instances of gut dysbiosis in ALS patients and mouse models; however, these studies are limited, and more information with well-controlled larger datasets is required to make a definitive judgment about the role of the gut microbiota in ALS pathogenesis. Overall this is an emerging field that is worthy of further investigation. The authors advocate for larger studies using modern metagenomic techniques to address the current knowledge gaps.

Association between exposure to a mixture of phenols, pesticides, and phthalates and obesity: Comparison of three statistical models

BACKGROUND

The evaluation of the chemical impact on human health is usually constrained to the analysis of the health effects of exposure to a single chemical or a group of similar chemicals at one time. The effects of chemical mixtures are seldom analyzed. In this study, we applied three statistical models to assess the association between the exposure to a mixture of seven xenobiotics (three phthalate metabolites, two phenols, and two pesticides) and obesity.

METHODS

Urinary levels of environmental phenols, pesticides, and phthalate metabolites were measured in adults who participated in the U.S.-based National Health and Nutrition Examination Survey (NHANES) from 2013 to 2014. Body examination was conducted to determine obesity. We fitted multivariable models, using generalized linear (here both logistic and linear) regression, weighted quantile sum (WQS) regression, and Bayesian kernel machine regression (BKMR) models to estimate the association between chemical exposures and obesity.

RESULTS

Of 1269 individuals included in our final analysis, 38.5% had general obesity and 58.0% had abdominal obesity. In the logistic regression model established for each single chemical, bisphenol S (BPS), mono (carboxyoctyl) phthalate (MCOP), and mono (2-ethyl-5-carboxypentyl) phthalate (MECPP) were associated with both general and abdominal obesity (fourth vs. first quartile). In linear regression, MCOP was associated with BMI and waist circumference. In WQS regression analysis, the WQS index was significantly associated with both general obesity (OR = 1.63, 95% CI: 1.21-2.20) and abdominal obesity (OR = 1.66, 95% CI: 1.18-2.34). MCOP, bisphenol A (BPA), bisphenol S (BPS), and mono ethyl phthalate (MEP) were the most heavily weighing chemicals. In BKMR analysis, the overall effect of mixture was significantly associated with general obesity when all the chemicals were at their 60th percentile or above it, compared to all of them at their 50th percentile. MCOP, BPA, and BPS showed positive trends. By contrast, MECPP showed a flat and modest inverse trend.

CONCLUSION

When comparing results from these three models, MCOP, BPA, and BPS were identified as the most important factors associated with obesity. We recommend estimating the joint effects of chemical mixtures by applying diverse statistical methods and interpreting their results together, considering their advantages and disadvantages.

Disease-modifying effects of metabolic perturbations in ALS/FTLD

Amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD) are two fatal neurodegenerative disorders with considerable clinical, pathological and genetic overlap. Both disorders are characterized by the accumulation of pathological protein aggregates that contain a number of proteins, most notably TAR DNA binding protein 43 kDa (TDP-43). Surprisingly, recent clinical studies suggest that dyslipidemia, high body mass index, and type 2 diabetes mellitus are associated with better clinical outcomes in ALS. Moreover, ALS and FTLD patients have a significantly lower incidence of cardiovascular disease, supporting the idea that an unfavorable metabolic profile may be beneficial in ALS and FTLD. The two most widely studied ALS/FTLD models, super-oxide dismutase 1 (SOD1) and TAR DNA binding protein of 43 kDA (TDP-43), reveal metabolic dysfunction and a positive effect of metabolic strategies on disease onset and/or progression. In addition, molecular studies reveal a role for ALS/FTLD-associated proteins in the regulation of cellular and whole-body metabolism. Here, we systematically evaluate these observations and discuss how changes in cellular glucose/lipid metabolism may result in abnormal protein aggregations in ALS and FTLD, which may have important implications for new treatment strategies for ALS/FTLD and possibly other neurodegenerative conditions.

Epidemiology and diagnostic process of amyotrophic lateral sclerosis as distinct from myelopathy: 5-year cohort study of whole-population in South Korea

OBJECTIVE

To investigate the incidence, prevalence, and demographic factors of all amyotrophic lateral sclerosis (ALS) patients diagnosed in South Korea from 2011 to 2015, and to analyze cases misdiagnosed as myelopathy.

METHODS

The whole population registered under the Korean National Health Insurance Service (KNHIS) was applied. All 4551 patients who were registered as having ALS code from 2011 to 2015 were included. For all ALS patients, the incidence, prevalence, and demographic factors were assessed. Trends of diagnosis for myelopathy, and surgery prior to confirmation of ALS diagnosis were identified.

RESULTS

When the whole 48,135,715 KNHIS population enrolled in 2015, the incidence of ALS in 2015 was estimated to be 1.68 per 100,000 person-years, and the prevalence was 6.49 per 100,000 persons. Life expectancy of ALS can be calculated as 3.9 years after the diagnosis, and the mean age of diagnosis was 59.5 ± 13.1. A total of 1902 patients diagnosed with myelopathy before a diagnosis of ALS accounted for 0.13% of all myelopathy patients, and 41.8% of all ALS patients. It took an average of 471.7 d to confirm a diagnosis of ALS after the myelopathy diagnosis. Among the patients finally diagnosed with ALS, more patients underwent surgery for myelopathy (n = 263, 13.8%) than among patients who were diagnosed with myelopathy alone, and underwent surgery (n = 141,148, 9.8%).

CONCLUSIONS

This whole-population nationwide demographic study confirmed the data from previous studies. Clinicians should consider the possibility of ALS when making a myelopathy diagnosis, especially if the symptoms are sufficiently severe to require surgery.

Functional and Endoscopic Indicators for Percutaneous Endoscopic Gastrostomy (PEG) in Amyotrophic Lateral Sclerosis Patients

(1) Background: Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative condition, whose bulbar involvement compromises language, swallowing, and airway protection. When oral nutrition is no longer adequate, percutaneous endoscopic gastroscopy (PEG) may be indicated. However, as exact timing is still debatable, we tried to find it. (2) Methods: A prospective cohort study was performed using fiber-optic endoscopic evaluation of swallowing (FEES), functional evaluation scales (ALS Functional Rating Scale-Revised (ALSFRS-R) and bulbar sub-score (ALSFRS-R-B)), lung function tests (like Forced Vital Capacity (FVC), Cough Peak Flow (CPF)) and anthropometric data. (3) Results: Twenty-three patients were enrolled (mean 65.4 ± 9.1 years, 60.9% males), 12 with spinal-onset. During the study period, 58 FEES were performed (1–4/patients). Even before formal PEG indication, suggestions were given to correct the alterations found. PEG was placed in 12 patients, on average 21.8 months after diagnosis (FVC = 69.9% ± 26.7%, ALSFRS-R-B = 7.7 ± 3.7, ALSFRS-R = 28.9 ± 12.3), and being 91.7% under ventilatory support. ALSFRS-R-B, CPF, FVC, and ALSFRS-R showed significant discriminant ability for PEG placement. Sensitivity and specificity were, respectively, ALSFRS-R-B ≤ 8 (100/90.9), CPF ≤ 205 (83.3), FVC ≤ 74 (83.3/74.2), and ALSFRS-R < 29 (83.3/65.1). (4) Conclusions: FEES provide additional information beyond formal PEG indication. ALSFRS-R-B score ≤ 8 was found as a best functional and noninvasive indicator for PEG placement in ALS patients.

The increasing importance of environmental conditions in amyotrophic lateral sclerosis

Amyotrophic lateral sclerosis (ALS) is the most common neurodegenerative disease affecting motor neurons (MNs). Although a small percentage of ALS has a familial origin, the vast majority of cases are sporadic in which genetic factors and environment interact with each other leading to disease onset in genetically predisposed individuals. In the current model of the disease, each individual has a determined genetic load, some degree of cell degeneration related to age and several risky environmental exposures. In this scenario, MN degeneration would occur when the sum of these factors reach a certain threshold. To date, an extensive list of environmental factors has been associated to ALS, including different categories, such as exposure to heavy metals and other toxicants, cyanotoxins or infectious agents. In addition, in recent years, lifestyle and other demographic parameters are gaining relevance in the genesis of the disease. Among them, physical activity, nutrition, body mass index, cardiovascular risk factors, autoimmune diseases and cancer are some of the conditions which have been related to the disease. In this review, we will discuss the potential mechanisms of environmental conditions in motor neuron degeneration. Understanding the role of each one of these factors as well as their interactions appears as a crucial step in order to develop new preventive, diagnostic and therapeutic approaches for ALS patients.

Association between macronutrient intake and amyotrophic lateral sclerosis prognosis

Objectives: Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease, and the nutritional state of ALS patients is associated with survival. The purpose of the present study was to investigate whether macronutrient intake at early stage of the disease was positively associated with survival and duration from symptom onset to death, tracheostomy, or non-invasive ventilation (NIV) in ALS.Methods: ALS patients diagnosed according to EI Escorial criteria were recruited from 2011 to 2016 and followed up until 2017, when they reached the endpoint of death, tracheostomy, or NIV use. Dietary intake was estimated based on a 24-hour recall conducted less than 2 years from symptom onset, and the survival time was defined as the duration from symptom onset to the endpoint.Results: ALS patients were categorized as short-term group (n=79) and long-term group (n=69) according to the mean survival time (33.03±14.01 months). Short-term survival was negatively associated with fat, protein, and meat intake, and positively associated with carbohydrate intake after adjustment for confounders. In addition, the survival time was positively associated with fat, protein, and meat intake but was not associated with carbohydrate intake.Discussion: The present study suggested that higher intake of fat and protein, particularly from meat at early stage of the disease, could prolong the survival of ALS patients. However, further clinical trials are necessary to confirm the beneficial effects of higher fat and protein intake on mortality in ALS patients.

Recent Advances in Studies on the Therapeutic Potential of Dietary Carotenoids in Neurodegenerative Diseases

Carotenoids, symmetrical tetraterpenes with a linear C40 hydrocarbon backbone, are natural pigment molecules produced by plants, algae, and fungi. Carotenoids have important functions in the organisms (including animals) that obtain them from food. Due to their characteristic structure, carotenoids have bioactive properties, such as antioxidant, anti-inflammatory, and autophagy-modulatory activities. Given the protective function of carotenoids, their levels in the human body have been significantly associated with the treatment and prevention of various diseases, including neurodegenerative diseases. In this paper, we review the latest studies on the effects of carotenoids on neurodegenerative diseases in humans. Furthermore, animal and cellular model studies on the beneficial effects of carotenoids on neurodegeneration are also reviewed. Finally, we discuss the possible mechanisms and limitations of carotenoids in the treatment and prevention of neurological diseases.

Pathogenic commonalities between spinal muscular atrophy and amyotrophic lateral sclerosis: Converging roads to therapeutic development

Spinal muscular atrophy (SMA) and amyotrophic lateral sclerosis (ALS) are the two most common motoneuron disorders, which share typical pathological hallmarks while remaining genetically distinct. Indeed, SMA is caused by deletions or mutations in the survival motor neuron 1 (SMN1) gene whilst ALS, albeit being mostly sporadic, can also be caused by mutations within genes, including superoxide dismutase 1 (SOD1), Fused in Sarcoma (FUS), TAR DNA-binding protein 43 (TDP-43) and chromosome 9 open reading frame 72 (C9ORF72). However, it has come to light that these two diseases may be more interlinked than previously thought. Indeed, it has recently been found that FUS directly interacts with an Smn-containing complex, mutant SOD1 perturbs Smn localization, Smn depletion aggravates disease progression of ALS mice, overexpression of SMN in ALS mice significantly improves their phenotype and lifespan, and duplications of SMN1 have been linked to sporadic ALS. Beyond genetic interactions, accumulating evidence further suggests that both diseases share common pathological identities such as intrinsic muscle defects, neuroinflammation, immune organ dysfunction, metabolic perturbations, defects in neuron excitability and selective motoneuron vulnerability. Identifying common molecular effectors that mediate shared pathologies in SMA and ALS would allow for the development of therapeutic strategies and targeted gene therapies that could potentially alleviate symptoms and be equally beneficial in both disorders. In the present review, we will examine our current knowledge of pathogenic commonalities between SMA and ALS, and discuss how furthering this understanding can lead to the establishment of novel therapeutic approaches with wide-reaching impact on multiple motoneuron diseases.

Exploring targets and therapies for amyotrophic lateral sclerosis: current insights into dietary interventions

A growing number of preclinical and human studies demonstrate a disease-modifying effect of nutritional state in amyotrophic lateral sclerosis (ALS). The management of optimal nutrition in ALS is complicated, as physiological, physical, and psychological effects of the disease need to be considered and addressed accordingly. In this regard, multidisciplinary care teams play an integral role in providing dietary guidance to ALS patients and their carers. However, with an increasing research focus on the use of dietary intervention strategies to manage disease symptoms and improve prognosis in ALS, many ALS patients are now seeking or are actively engaged in using complementary and alternative therapies that are dietary in nature. In this article, we review the aspects of appetite control, energy balance, and the physiological effects of ALS relative to their impact on overall nutrition. We then provide current insights into dietary interventions for ALS, considering the mechanisms of action of some of the common dietary interventions used in ALS, discussing their validity in the context of clinical trials.