Muscle Involvement in Amyotrophic Lateral Sclerosis: Understanding the Pathogenesis and Advancing Therapeutics

HAP/ClpP-mediated disaggregation and degradation of Mutant SOD1 aggregates: A potential therapeutic strategy for Amyotrophic lateral sclerosis (ALS)

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease marked by the accumulation of misfolded Cu/Zn superoxide dismutase (SOD1) protein aggregates in motor neurons, leading to progressive motor dysfunction and ultimately death. While the molecular chaperone heat shock protein 104 (Hsp104) has been shown to reduce protein misfolding by disaggregating protein aggregates, fully degrading these disaggregated proteins remains a significant challenge. In this study, we have investigated the effects of Hsp104 and its hyperactive variant, HAP, in combination with caseinolytic protease P (CIpP), on the disaggregation and degradation of SOD1 aggregates. Using laser confocal microscopy, fluorescence loss in photobleaching (FLIP), and biomolecular fluorescence complementation (BiFC)-fluorescence resonance energy transfer (FRET) assays, we demonstrate that Hsp104 effectively disaggregates SOD1 aggregates across 14 different G93 mutants, classified based on the properties of substituted amino acids, thus restoring protein mobility. Notably, the HAP/CIpP system not only disaggregates ALS-associated SOD1G93A aggregates but also promotes their proteolytic degradation, as evidenced by a significant reduction in high-order oligomers observed through BiFC and FRET assays. This dual mechanism of action presents. the HAP/CIpP system holds significant therapeutic potential for ALS and other neurodegenerative diseases characterized by protein aggregates, as it enables both effective disaggregation and degradation of toxic protein aggregates, thereby maintaining protein homeostasis.

Synergistic Effects of Riluzole and Sodium Butyrate on Barrier Function and Disease Progression of Amyotrophic Lateral Sclerosis Through the Gut-Neuron Axis

Emerging evidence has shown that gut-brain barrier dysfunction occurs at the early stages of ALS. Previous studies demonstrated that sodium butyrate significantly prolonged the life span of ALS mice. Riluzole is the first FDA-approved drug for ALS treatment. We hypothesize that Riluzole and sodium butyrate combined treatment further decreases aggregation of the h-SOD1G93A, restores the gut-brain barrier function, and delays ALS progression. SOD1G93A mice (9-10-week-old) were treated with Riluzole (10 mg/kg, I.P. daily), sodium butyrate (2% in drinking water), or Riluzole and sodium butyrate combination for 6 weeks. The Riluzole/butyrate combination showed a significantly longer rotarod time, increased grip strength, and enhanced intestinal barrier, as compared with Riluzole or sodium butyrate-only treatment. More reduction of h-SOD1G93A aggregation was observed in the colon, spinal cord lumbar, and brain cortex with Riluzole and sodium butyrate combination, compared with Riluzole or sodium butyrate-only treatment. Tight junction proteins (ZO-1 and Claudin-5) significantly increased in the colon, spinal cord lumbar, and brain cortex of mice with Riluzole and sodium butyrate treatment. The Riluzole and sodium butyrate combination reduced serum lipopolysaccharides and h-SOD1G93A aggregation, and inflammatory cytokines more than those in Riluzole or sodium butyrate-only treatment. Overall, Riluzole and sodium butyrate treatment is more effective than either Riluzole or sodium butyrate-only in delaying ALS progress. It provides a potential therapeutic strategy and mechanism by restoring barrier function through the gut-brain axis for ALS.

Nutritional Interventions in Amyotrophic Lateral Sclerosis: From Ketogenic Diet and Neuroprotective Nutrients to the Microbiota-Gut-Brain Axis Regulation

Amyotrophic lateral sclerosis (ALS) is a complex neurodegenerative disease with significant challenges in diagnosis and treatment. Recent research has highlighted the complex nature of ALS, encompassing behavioral impairments in addition to its neurological manifestations. While several medications have been approved to slow disease progression, ongoing research is focused on identifying new therapeutic targets. The current review focuses on emerging therapeutic strategies and personalized approaches aimed at improving patient outcomes. Recent advancements highlight the importance of targeting additional pathways such as mitochondrial dysfunction and neuroinflammation to develop more effective treatments. Personalized medicine, including genetic testing and biomarkers, is proving valuable in stratifying patients and tailoring treatment options. Complementary therapies, such as nutritional interventions like the ketogenic diet and microbiome modulation, also show promise. This review emphasizes the need for a multidisciplinary approach that integrates early diagnosis, targeted treatments, and supportive care to address the multisystemic nature of ALS and improve the quality of life for patients.

Actual needs of patients with amyotrophic lateral sclerosis: a qualitative study from Wuhan, China

BACKGROUND

Amyotrophic Lateral Sclerosis (ALS) is a progressive and fatal neurodegenerative disorder that significantly impacts individuals and families. Previous research on ALS has predominantly focused on its pathophysiology, genetic factors, and potential therapeutic interventions. While these aspects are essential for understanding and treating the disease, there has been a growing recognition of the importance of studying patients' actual needs. Understanding these needs is vital for developing patient-centered care models that can enhance the well-being of ALS patients. However, existing studies on patients' needs are often limited in scope. Many are conducted in Western countries, and the results may not be directly applicable to patients in other cultural and socioeconomic contexts. China, with its large population and diverse cultural, economic, and healthcare landscapes, presents a unique setting for studying ALS patients' needs. At the same time, traditional Chinese medicine (TCM) practices are deeply ingrained in their healthcare system and may affect the way people with ALS seek treatment and manage their condition. Therefore, these differences may lead to differences in the actual needs of ALS patients in China. In conclusion, this qualitative study on the actual needs of ALS patients in China aims to bridge the gap in the existing research. By exploring these needs, it can provide valuable insights for healthcare providers, policymakers, and researchers, ultimately contributing to the improvement of care and quality of life for ALS patients in China.

METHOD

We carried out a qualitative study using an empirical phenomenological approach. Individual in-depth interviews were performed among 22 people with ALS from the motor neuron disease rehabilitation center of a tertiary Chinese medicine hospital in China, and the interview content was analyzed qualitatively. Interview recordings were converted to text content by NVivo 11.0 software and analyzed using Colaizzi's phenomenological method.

RESULT

Three main themes were identified in this study: (1) Demand for healthcare services, (2) Emotional requirements, (3) Functional requirements. In addition, 8 sub-themes were extracted as the actual needs of ALS patients.

CONCLUSION

This study is based on the real experience of ALS patients after diagnosis, and a deep understanding of these experiences can explore the actual needs of patients from many aspects and give reasonable advice and help. Given the particularity of the disease and the uncertainty of treatment, patients will have practical needs for relevant medical support, emotional requirements, physical functions, and other aspects during the period of illness, and the corresponding support is an effective measure to reduce the burden on patients.

Muscle-specific Bet1L knockdown induces neuromuscular denervation, motor neuron degeneration, and motor dysfunction in a rat model of familial ALS

Amyotrophic lateral sclerosis (ALS) is a neuromuscular disease characterized by specific loss of motor neurons in the spinal cord and brain stem. Although ALS has historically been characterized as a motor neuron disease, there is evidence that motor neurons degenerate in a retrograde manner, beginning in the periphery at the neuromuscular junctions (NMJs) and skeletal muscle. We recently reported a vesicle trafficking protein Bet1L (Bet1 Golgi Vesicular Membrane Trafficking Protein Like) as a new molecule possibly linked to NMJ degeneration in ALS. In this study, we tested the hypothesis that Bet1L gene silencing in skeletal muscle could influence NMJ integrity, motor neuron function, and survival in a rat model of familial ALS (SOD1G93A transgenic). Small interfering RNA (siRNA) targeting the Bet1L gene was injected on a weekly basis into the hindlimb muscle of pre-symptomatic ALS and wild-type (WT) rats. After 3 weeks, intramuscular Bet1L siRNA injection significantly increased the number of denervated NMJs in the injected muscle. Bet1L knockdown decreased motor neuron size in the lumbar spinal cord, which innervated the siRNA-injected hindlimb. Impaired motor function was identified in the hindlimbs of Bet1L siRNA-injected rats. Notably, the effects of Bet1L knockdown on NMJ and motor neuron degeneration were more significant in ALS rats when compared to WT rats. Together, Bet1L knockdown induces denervation of NMJs, but also this knockdown accelerates the disease progression in ALS. Our results provide new evidence to support the potential roles of Bet1L as a key molecule in NMJ maintenance and ALS pathogenesis.

Mitochondrial microRNAs: Key Drivers in Unraveling Neurodegenerative Diseases

MicroRNAs (miRNAs) are a class of small non-coding RNAs (ncRNAs) crucial for regulating gene expression at the post-transcriptional level. Recent evidence has shown that miRNAs are also found in mitochondria, organelles that produce energy in the cell. These mitochondrial miRNAs, also known as mitomiRs, are essential for regulating mitochondrial function and metabolism. MitomiRs can originate from the nucleus, following traditional miRNA biogenesis pathways, or potentially from mitochondrial DNA, allowing them to directly affect gene expression and cellular energy dynamics within the mitochondrion. While miRNAs have been extensively investigated, the function and involvement of mitomiRs in the development of neurodegenerative disorders like Alzheimer's disease, Parkinson's disease, and amyotrophic lateral sclerosis remain to be elucidated. This review aims to discuss findings on the role of mitomiRs in such diseases and their potential as therapeutic targets, as well as to highlight future research directions.

New perspectives of the role of skeletal muscle derived extracellular vesicles in the pathogenesis of amyotrophic lateral sclerosis: the 'dying back' hypothesis

Amyotrophic lateral sclerosis (ALS), is a progressive neurodegenerative disease that affects nerve cells in the brain and the spinal cord, and is characterized by muscle weakness, paralysis and ultimately, respiratory failure. The exact causes of ALS are not understood, though it is believed to combine genetic and environmental factors. Until now, it was admitted that motor neurons (MN) in the brain and spinal cord degenerate, leading to muscle weakness and paralysis. However, as ALS symptoms typically begin with muscle weakness or stiffness, a new hypothesis has recently emerged to explain the development of the pathology, that is, the 'dying back hypothesis', suggesting that this degeneration starts at the connections between MN and muscles, resulting in the loss of muscle function. Over time, this damage extends along the length of the MN, ultimately affecting their cell bodies in the spinal cord and brain. While the dying back hypothesis provides a potential framework for understanding the progression of ALS, the exact mechanisms underlying the disease remain complex and not fully understood. In this review, we are positioning the role of extracellular vesicles as new actors in ALS development.

From Brain to Muscle: The Role of Muscle Tissue in Neurodegenerative Disorders

Neurodegenerative diseases (NDs), like amyotrophic lateral sclerosis (ALS), Alzheimer's disease (AD), and Parkinson's disease (PD), primarily affect the central nervous system, leading to progressive neuronal loss and motor and cognitive dysfunction. However, recent studies have revealed that muscle tissue also plays a significant role in these diseases. ALS is characterized by severe muscle wasting as a result of motor neuron degeneration, as well as alterations in gene expression, protein aggregation, and oxidative stress. Muscle atrophy and mitochondrial dysfunction are also observed in AD, which may exacerbate cognitive decline due to systemic metabolic dysregulation. PD patients exhibit muscle fiber atrophy, altered muscle composition, and α-synuclein aggregation within muscle cells, contributing to motor symptoms and disease progression. Systemic inflammation and impaired protein degradation pathways are common among these disorders, highlighting muscle tissue as a key player in disease progression. Understanding these muscle-related changes offers potential therapeutic avenues, such as targeting mitochondrial function, reducing inflammation, and promoting muscle regeneration with exercise and pharmacological interventions. This review emphasizes the importance of considering an integrative approach to neurodegenerative disease research, considering both central and peripheral pathological mechanisms, in order to develop more effective treatments and improve patient outcomes.

Edaravone: A Possible Treatment for Acute Lung Injury

Despite technological advances in science and medicine, acute lung injury (ALI) is still associated with high mortality rates in the ICU. Therefore, finding novel drugs and treatment approaches is crucial to preventing ALI. Drug repurposing is a common practice in clinical research, primarily for drugs that have previously received approval for use in patients, to investigate novel uses of drugs and therapies. One such medication is edaravone, which is a highly effective free-radical scavenger that also has anti-inflammatory, anti-apoptotic, antioxidant, and anti-fibrotic effects. Both basic and clinical studies have shown that edaravone can treat different types of lung injury through its distinct properties. Edaravone exhibits significant protective benefits and holds promising clinical treatment potential for ALI caused by diverse factors, thereby offering a novel approach to treating ALI. This study aims to provide new insights and treatment options for ALI by reviewing both basic and clinical research on the use of edaravone. The focus is on evaluating the effectiveness of edaravone in treating ALI caused by various factors.

Insights into Dysregulated Neurological Biomarkers in Cancer

The link between neurodegenerative diseases (NDs) and cancer has generated greater interest in biomedical research, with decades of global studies investigating neurodegenerative biomarkers in cancer to better understand possible connections. Tau, amyloid-β, α-synuclein, SOD1, TDP-43, and other proteins associated with nervous system diseases have also been identified in various types of solid and malignant tumors, suggesting a potential overlap in pathological processes. In this review, we aim to provide an overview of current evidence on the role of these proteins in cancer, specifically examining their effects on cell proliferation, apoptosis, chemoresistance, and tumor progression. Additionally, we discuss the diagnostic and therapeutic implications of this interconnection, emphasizing the importance of further research to completely comprehend the clinical implications of these proteins in tumors. Finally, we explore the challenges and opportunities in targeting these proteins for the development of new targeted anticancer therapies, providing insight into how to integrate knowledge of NDs in oncology research.

Mitochondrial Dysfunction in Sporadic Amyotrophic Lateral Sclerosis Patients: Insights from High-Resolution Respirometry

Amyotrophic lateral sclerosis is a severe neurodegenerative disease whose exact cause is still unclear. Currently, research attention is turning to the mitochondrion as a critical organelle of energy metabolism. Current knowledge is sufficient to confirm the involvement of the mitochondria in the pathophysiology of the disease, since the mitochondria are involved in many processes in the cell; however, the exact mechanism of involvement is still unclear. We used peripheral blood mononuclear cells isolated from whole fresh blood from patients with amyotrophic lateral sclerosis for measurement and matched an age- and sex-matched set of healthy subjects. The group of patients consisted of patients examined and diagnosed at the neurological clinic of the University Hospital Martin. The set of controls consisted of healthy individuals who were actively searched, and controls were selected on the basis of age and sex. The group consisted of 26 patients with sporadic forms of ALS (13 women, 13 men), diagnosed based on the definitive criteria of El Escorial. The average age of patients was 54 years, and the average age of healthy controls was 56 years. We used a high-resolution O2K respirometry method, Oxygraph-2k, to measure mitochondrial respiration. Basal respiration was lower in patients by 29.48%, pyruvate-stimulated respiration (respiratory chain complex I) was lower by 29.26%, and maximal respiratory capacity was lower by 28.15%. The decrease in succinate-stimulated respiration (respiratory chain complex II) was 26.91%. Our data confirm changes in mitochondrial respiration in ALS patients, manifested by the reduced function of complex I and complex II of the respiratory chain. These defects are severe enough to confirm this disease's hypothesized mitochondrial damage. Therefore, research interest in the future should be directed towards a deeper understanding of the involvement of mitochondria and respiratory complexes in the pathophysiology of the disease. This understanding could develop new biomarkers in diagnostics and subsequent therapeutic interventions.

Prognostic value of geriatric nutritional risk index in patients with amyotrophic lateral sclerosis

BACKGROUND

The geriatric nutritional risk index (GNRI) is a prognostic indicator for several diseases, meanwhile, nutrition and inflammation play important roles in the disease progression of amyotrophic lateral sclerosis (ALS). However, the association between the GNRI and ALS remains unknown.

METHODS

443 patients diagnosed with ALS were divided into two groups based on the GNRI levels. Associations between GNRI and survival time were analyzed using Kaplan-Meier curves and compared by the log-rank test. Univariate and multivariate analyses were used to assess their prognostic values for survival time. Spearman correlation analysis was used to evaluate the correlation coefficients between GNRI and other clinical variables.

RESULTS

No significant differences were found in diagnostic delay between the two groups. The onset age and disease progression rate (DPR) were significantly lower in high GNRI group while forced vital capacity (FVC), revised version of the ALS functional rating scale (ALSFRS-R), serum albumin and body mass index (BMI) were significantly lower in low GNRI group. Lower GNRI levels were linked with shorter ALS patients' survival time by Kaplan-Meier curves. The univariate and multivariate analysis identified the onset age, gender, onset site, diagnostic delay, DRP and GNRI as predictors of survival time in patients with ALS.

CONCLUSION

Nutritional status was closely corelated with ALS progression. The GNRI may be used as a potential prognostic indictor for ALS patients.

Edaravone: A Novel Possible Drug for Cancer Treatment?

Despite significant advancements in understanding the causes and progression of tumors, cancer remains one of the leading causes of death worldwide. In light of advances in cancer therapy, there has been a growing interest in drug repurposing, which involves exploring new uses for medications that are already approved for clinical use. One such medication is edaravone, which is currently used to manage patients with cerebral infarction and amyotrophic lateral sclerosis. Due to its antioxidant and anti-inflammatory properties, edaravone has also been investigated for its potential activities in treating cancer, notably as an anti-proliferative and cytoprotective drug against side effects induced by traditional cancer therapies. This comprehensive review aims to provide updates on the various applications of edaravone in cancer therapy. It explores its potential as a standalone antitumor drug, either used alone or in combination with other medications, as well as its role as an adjuvant to mitigate the side effects of conventional anticancer treatments.