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Scientific Reports Jun 2024Disrupted proteome homeostasis (proteostasis) in amyotrophic lateral sclerosis (ALS) has been a major focus of research in the past two decades. However, the...
Disrupted proteome homeostasis (proteostasis) in amyotrophic lateral sclerosis (ALS) has been a major focus of research in the past two decades. However, the proteostasis processes that become disturbed in ALS are not fully understood. Obtaining more detailed knowledge of proteostasis disruption in association with different ALS-causing mutations will improve our understanding of ALS pathophysiology and may identify novel therapeutic targets and strategies for ALS patients. Here we describe the development and use of a novel high-content analysis (HCA) assay to investigate proteostasis disturbances caused by the expression of several ALS-causing gene variants. This assay involves the use of conformationally-destabilised mutants of firefly luciferase (Fluc) to examine protein folding/re-folding capacity in NSC-34 cells expressing ALS-associated mutations in the genes encoding superoxide dismutase-1 (SOD1) and cyclin F (CCNF). We demonstrate that these Fluc isoforms can be used in high-throughput format to report on reductions in the activity of the chaperone network that result from the expression of SOD1, providing multiplexed information at single-cell resolution. In addition to SOD1 and CCNF, NSC-34 models of ALS-associated TDP-43, FUS, UBQLN2, OPTN, VCP and VAPB mutants were generated that could be screened using this assay in future work. For ALS-associated mutant proteins that do cause reductions in protein quality control capacity, such as SOD1, this assay has potential to be applied in drug screening studies to identify candidate compounds that can ameliorate this deficiency.
Topics: Amyotrophic Lateral Sclerosis; Proteostasis; Humans; Superoxide Dismutase-1; Protein Folding; Mutation; Cell Line; Mice; Animals
PubMed: 38879591
DOI: 10.1038/s41598-024-64366-0 -
Respiratory Physiology & Neurobiology Jun 2024Assessing cough effectiveness, using Cough Peak Flow, is crucial for patients with Neuromuscular Diseases, such as Amyotrophic Lateral Sclerosis. Impaired cough function...
Assessing cough effectiveness, using Cough Peak Flow, is crucial for patients with Neuromuscular Diseases, such as Amyotrophic Lateral Sclerosis. Impaired cough function can contribute to respiratory decline and failure. The goal of the study is to determine the correlation between diaphragmatic excursion and cough expiratory phase, potentially utilizing ultrasonographic indices to estimate Cough Peak Flow in these patients. Twenty-two patients were enrolled in this study. The upward displacement of the diaphragm was measured with ultrasonography during voluntary cough expiration and Cough Peak Flow was simultaneously measured. A multivariable linear regression model was built to quantify the association between Cough Peak Flow and diaphragm expiratory excursion. There is significative relationship between Cough Peak Flow and diaphragm excursion with a Pearson's r coefficient of 0.86 observed in the patients group. Multiple linear regression analysis for Cough Peak Flow (Adjusted R = 0.86) revealed significant associations between Cough Peak Flow and expiratory excursion (adjusted β-coefficient: 64.78, 95 %, CI: 51.50-78.07, p<0.001) and sex (adjusted β-coefficient: -69.06; 95 % CI: -109.98 to -28.15, p=0.001). Our results predict the cough effectiveness by using M-mode diaphragmatic sonography with a potentially significant impact on therapeutic choices.
PubMed: 38879100
DOI: 10.1016/j.resp.2024.104299 -
Developmental Cell Jun 2024Amyotrophic lateral sclerosis (ALS) is a rapidly progressing, highly heterogeneous neurodegenerative disease, underscoring the importance of obtaining information to...
Amyotrophic lateral sclerosis (ALS) is a rapidly progressing, highly heterogeneous neurodegenerative disease, underscoring the importance of obtaining information to personalize clinical decisions quickly after diagnosis. Here, we investigated whether ALS-relevant signatures can be detected directly from biopsied patient fibroblasts. We profiled familial ALS (fALS) fibroblasts, representing a range of mutations in the fused in sarcoma (FUS) gene and ages of onset. To differentiate FUS fALS and healthy control fibroblasts, machine-learning classifiers were trained separately on high-content imaging and transcriptional profiles. "Molecular ALS phenotype" scores, derived from these classifiers, captured a spectrum from disease to health. Interestingly, these scores negatively correlated with age of onset, identified several pre-symptomatic individuals and sporadic ALS (sALS) patients with FUS-like fibroblasts, and quantified "movement" of FUS fALS and "FUS-like" sALS toward health upon FUS ASO treatment. Taken together, these findings provide evidence that non-neuronal patient fibroblasts can be used for rapid, personalized assessment in ALS.
PubMed: 38878774
DOI: 10.1016/j.devcel.2024.05.011 -
Cell Death & Disease Jun 2024A CAG repeat sequence in the ATXN2 gene encodes a polyglutamine (polyQ) tract within the ataxin-2 (ATXN2) protein, showcasing a complex landscape of functions that have... (Review)
Review
A CAG repeat sequence in the ATXN2 gene encodes a polyglutamine (polyQ) tract within the ataxin-2 (ATXN2) protein, showcasing a complex landscape of functions that have been progressively unveiled over recent decades. Despite significant progresses in the field, a comprehensive overview of the mechanisms governed by ATXN2 remains elusive. This multifaceted protein emerges as a key player in RNA metabolism, stress granules dynamics, endocytosis, calcium signaling, and the regulation of the circadian rhythm. The CAG overexpansion within the ATXN2 gene produces a protein with an extended poly(Q) tract, inducing consequential alterations in conformational dynamics which confer a toxic gain and/or partial loss of function. Although overexpanded ATXN2 is predominantly linked to spinocerebellar ataxia type 2 (SCA2), intermediate expansions are also implicated in amyotrophic lateral sclerosis (ALS) and parkinsonism. While the molecular intricacies await full elucidation, SCA2 presents ATXN2-associated pathological features, encompassing autophagy impairment, RNA-mediated toxicity, heightened oxidative stress, and disruption of calcium homeostasis. Presently, SCA2 remains incurable, with patients reliant on symptomatic and supportive treatments. In the pursuit of therapeutic solutions, various studies have explored avenues ranging from pharmacological drugs to advanced therapies, including cell or gene-based approaches. These endeavours aim to address the root causes or counteract distinct pathological features of SCA2. This review is intended to provide an updated compendium of ATXN2 functions, delineate the associated pathological mechanisms, and present current perspectives on the development of innovative therapeutic strategies.
Topics: Humans; Ataxin-2; Peptides; Animals; Amyotrophic Lateral Sclerosis; Spinocerebellar Ataxias
PubMed: 38877004
DOI: 10.1038/s41419-024-06812-5 -
Stem Cell Reports Jun 2024Induced pluripotent stem cell (iPSC)-derived motor neurons (MNs) from patients with amyotrophic lateral sclerosis (ALS) and the C9ORF72 hexanucleotide repeat expansion...
Induced pluripotent stem cell (iPSC)-derived motor neurons (MNs) from patients with amyotrophic lateral sclerosis (ALS) and the C9ORF72 hexanucleotide repeat expansion (HRE) have multiple cellular phenotypes, but which of these accurately reflect the biology underlying the cell-specific vulnerability of ALS is uncertain. We therefore compared phenotypes due to the C9ORF72 HRE in MNs with sensory neurons (SNs), which are relatively spared in ALS. The iPSC models were able to partially reproduce the differential gene expression seen between adult SNs and MNs. We demonstrated that the typical hallmarks of C9ORF72-ALS, including RNA foci and dipeptide formation, as well as specific axonal transport defects, occurred equally in MNs and SNs, suggesting that these in vitro phenotypes are not sufficient to explain the cell-type selectivity of ALS in isolation.
PubMed: 38876108
DOI: 10.1016/j.stemcr.2024.05.008 -
HGG Advances Jun 2024The high heritability of amyotrophic lateral sclerosis (ALS) contrasts with its low molecular diagnosis rate post-genetic testing, pointing to potential undiscovered...
The high heritability of amyotrophic lateral sclerosis (ALS) contrasts with its low molecular diagnosis rate post-genetic testing, pointing to potential undiscovered genetic factors. To aid the exploration of these factors, we introduced EpiOut, an algorithm to identify chromatin accessibility outliers that are regions exhibiting divergent accessibility from the population baseline in a single or few samples. Annotation of accessible regions with histone chromatin immunoprecipitation sequencing and Hi-C indicates that outliers are concentrated in functional loci, especially among promoters interacting with active enhancers. Across different omics levels, outliers are robustly replicated, and chromatin accessibility outliers are reliable predictors of gene expression outliers and aberrant protein levels. When promoter accessibility does not align with gene expression, our results indicate that molecular aberrations are more likely to be linked to post-transcriptional regulation rather than transcriptional regulation. Our findings demonstrate that the outlier detection paradigm can uncover dysregulated regions in rare diseases. EpiOut is available at github.com/uci-cbcl/EpiOut.
PubMed: 38872308
DOI: 10.1016/j.xhgg.2024.100318 -
CNS Neuroscience & Therapeutics Jun 2024Amyotrophic lateral sclerosis (ALS) is a severe neurodegenerative disease characterized by progressive death of upper and lower motor neurons, leading to generalized...
Arctigenin derivative A-1 ameliorates motor dysfunction and pathological manifestations in SOD1 transgenic mice via the AMPK/SIRT1/PGC-1α and AMPK/SIRT1/IL-1β/NF-κB pathways.
AIM
Amyotrophic lateral sclerosis (ALS) is a severe neurodegenerative disease characterized by progressive death of upper and lower motor neurons, leading to generalized muscle atrophy, paralysis, and even death. Mitochondrial damage and neuroinflammation play key roles in the pathogenesis of ALS. In the present study, the efficacy of A-1, a derivative of arctigenin with AMP-activated protein kinase (AMPK) and silent information regulator 1 (SIRT1) activation for ALS, was investigated.
METHODS
A-1 at 33.3 mg/kg was administrated in SOD1 transgenic mice orally from the 13th week for a 6-week treatment period. Motor ability was assessed before terminal anesthesia. Muscle atrophy and fibrosis, motor neurons, astrocytes, and microglia in the spinal cord were evaluated by H&E, Masson, Sirius Red, Nissl, and immunohistochemistry staining. Protein expression was detected with proteomics analysis, Western blotting, and ELISA. Mitochondrial adenosine triphosphate (ATP) and malondialdehyde (MDA) levels were measured using an assay kit.
RESULTS
A-1 administration in SOD1 mice enhanced mobility, decreased skeletal muscle atrophy and fibrosis, mitigated loss of spinal motor neurons, and reduced glial activation. Additionally, A-1 treatment improved mitochondrial function, evidenced by elevated ATP levels and increased expression of key mitochondrial-related proteins. The A-1 treatment group showed decreased levels of IL-1β, pIκBα/IκBα, and pNF-κB/NF-κB.
CONCLUSIONS
A-1 treatment reduced motor neuron loss, improved gastrocnemius atrophy, and delayed ALS progression through the AMPK/SIRT1/PGC-1α pathway, which promotes mitochondrial biogenesis. Furthermore, the AMPK/SIRT1/IL-1β/NF-κB pathway exerted neuroprotective effects by reducing neuroinflammation. These findings suggest A-1 as a promising therapeutic approach for ALS.
Topics: Animals; Mice, Transgenic; Sirtuin 1; Mice; NF-kappa B; AMP-Activated Protein Kinases; Furans; Amyotrophic Lateral Sclerosis; Interleukin-1beta; Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha; Lignans; Signal Transduction; Superoxide Dismutase-1; Male; Motor Neurons; Spinal Cord
PubMed: 38872258
DOI: 10.1111/cns.14692 -
Heliyon Jun 2024The timely introduction of non-invasive ventilation (NIV) is extremely relevant in the multidisciplinary management of patients affected by amyotrophic lateral sclerosis...
The timely introduction of non-invasive ventilation (NIV) is extremely relevant in the multidisciplinary management of patients affected by amyotrophic lateral sclerosis (ALS) and is based on the proper identification of red flags for early diaphragmatic exhaustion. Polygraphic sleep recording may provide insightful information on the ongoing respiratory impairment; in particular, atypical breathing patterns need to be recognized, as the application of current guidelines for sleep-related hypoxemia or sleep apnea may be insufficient for detecting early signs of diaphragmatic fatigue. We report the case of a 51-year-old man affected by ALS who was asymptomatic for breathing impairment, but whose nocturnal polysomnographic recording, despite not significant for obstructive sleep apnea nor for conventional hypoventilatory patterns, strongly suggested initial respiratory failure, as lately confirmed by the pulmonary follow-up. We discuss the advantages of including sleep recording in the clinical work-up of patients affected by ALS.
PubMed: 38868068
DOI: 10.1016/j.heliyon.2024.e32250 -
BMC Complementary Medicine and Therapies Jun 2024Traditional Chinese medicine (TCM) is widely used by patients with amyotrophic lateral sclerosis (ALS). However, their reasons and experience in using TCM have received...
BACKGROUND AND AIM
Traditional Chinese medicine (TCM) is widely used by patients with amyotrophic lateral sclerosis (ALS). However, their reasons and experience in using TCM have received insufficient attention. Therefore, we conducted a mixed method study to gain insights into this issue.
MATERIALS AND METHODS
This study was conducted on the basis of the China Amyotrophic Lateral Sclerosis Registry of Patients with Traditional Chinese Medicine (CARE-TCM). Data were collected from Dongzhimen Hospital through a mixed method approach, including a questionnaire and a semi-structured interview. Patients with ALS who were using TCM when they were initially registered with CARE-TCM and who had been followed-up for over six months were recruited. The questionnaires' outcomes were statistically outlined, and the interview transcripts were thematically analysed to identify themes and sub-themes.
RESULTS
Fifty-two and sixteen patients were included in the questionnaire and semi-structured interview groups, respectively. Patients used TCM with the hope of regulating their body holistically to improve nonmotor symptoms and quality of life (QOL). Those who recognised TCM as ineffective tended to discontinue it after a three-month trial period. Although quality was a major concern, herbal medicine (HM) was the most frequently used modality among all participants (n = 52), with the majority (n = 44, 84.6%) continuing to use it. Patients emphasised in-person consultations as a crucial part of TCM treatment. However, the disability caused by disease often made this interaction unattainable.
CONCLUSION
Nonmotor symptoms and QOL hold substantial importance for patients with ALS using TCM. HM is a more suitable modality than other TCM treatment modalities, but patients are facing challenges in seeking HM treatment. It is necessary to promote the implementation of hierarchical diagnosis and treatment, thus making TCM more accessible.
TRIAL REGISTRATION
ClinicalTrials.gov identifier: NCT04885374 (registered on May 13, 2021).
Topics: Humans; Amyotrophic Lateral Sclerosis; Medicine, Chinese Traditional; Female; Male; Middle Aged; Surveys and Questionnaires; Aged; China; Adult; Quality of Life; Qualitative Research
PubMed: 38867220
DOI: 10.1186/s12906-024-04513-2 -
Nature Communications Jun 2024Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease due to gradual motoneurons (MN) degeneration. Among the processes associated to ALS...
Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease due to gradual motoneurons (MN) degeneration. Among the processes associated to ALS pathogenesis, there is the formation of cytoplasmic inclusions produced by aggregation of mutant proteins, among which the RNA binding protein FUS. Here we show that, in neuronal cells and in iPSC-derived MN expressing mutant FUS, such inclusions are significantly reduced in number and dissolve faster when the RNA mA content is diminished. Interestingly, stress granules formed in ALS conditions showed a distinctive transcriptome with respect to control cells, which reverted to similar to control after mA downregulation. Notably, cells expressing mutant FUS were characterized by higher mA levels suggesting a possible link between mA homeostasis and pathological aggregates. Finally, we show that FUS inclusions are reduced also in patient-derived fibroblasts treated with STM-2457, an inhibitor of METTL3 activity, paving the way for its possible use for counteracting aggregate formation in ALS.
Topics: RNA-Binding Protein FUS; Amyotrophic Lateral Sclerosis; Humans; Motor Neurons; Induced Pluripotent Stem Cells; Cytoplasmic Granules; Fibroblasts; Adenosine; Methyltransferases; Mutation; Inclusion Bodies; Stress Granules; Transcriptome
PubMed: 38866783
DOI: 10.1038/s41467-024-49416-5