Amyotrophic Lateral Sclerosis: Recent Considerations for Diagnosis, Pathogenesis and Therapy

A special issue of Brain Sciences (ISSN 2076-3425). This special issue belongs to the section "Neuromuscular and Movement Disorders".

Deadline for manuscript submissions: closed (15 September 2024) | Viewed by 5265

Special Issue Editor


E-Mail Website
Guest Editor
Division of Neurology, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
Interests: ALS; motor cortex; corticomotoneuronal system; preclinical
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

Amyotrophic lateral sclerosis (ALS/MND) is a unique type of human neurodegeneration disease characterised by various phenotypes, including frontotemporal dementia. These are predicated by genetic, environmental, lifestyle and epigenetic influences. However, no naturally occurring or induced animal models truly recapitulate this human disease. ALS has a preclinical period of variable length, likely extending to years or decades, and at clinical onset, the cellular cascades associated with neuronal death are irreversible. Therefore, there is a need for biomarkers to identify preclinical disease. C9ORF72, SOD1, FUS and TARDBP are causative genes accounting for <10% of ALS, and the identification of “risk genes” (>70) contributing to sporadic ALS in association with environmental and lifestyle factors is necessary. Epigenetic modification fine-tunes gene expression in response to the environment, and epigenetic profile alterations may occur in the offspring of exposed individuals with intergenerational inheritance. Extra-nuclear aggregation of TDP-43 is a hallmark of ALS, and evidence indicates that it spreads cortico-fugally, intricately related to the corticomotoneuronal system, suggesting that ALS is a primary brain disease. ALS is increasingly studied using patient-derived iPSCs to investigate early stages of the disease, model risk factors, apply gene editing using CRISPR and explore new therapies.

Prof. Dr. Andrew Eisen
Guest Editor

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Brain Sciences is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2200 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • amyotrophic lateral sclerosis
  • genes
  • environment
  • epigenome
  • TDP-43
  • phenotypes

Benefits of Publishing in a Special Issue

  • Ease of navigation: Grouping papers by topic helps scholars navigate broad scope journals more efficiently.
  • Greater discoverability: Special Issues support the reach and impact of scientific research. Articles in Special Issues are more discoverable and cited more frequently.
  • Expansion of research network: Special Issues facilitate connections among authors, fostering scientific collaborations.
  • External promotion: Articles in Special Issues are often promoted through the journal's social media, increasing their visibility.
  • e-Book format: Special Issues with more than 10 articles can be published as dedicated e-books, ensuring wide and rapid dissemination.

Further information on MDPI's Special Issue polices can be found here.

Published Papers (4 papers)

Order results
Result details
Select all
Export citation of selected articles as:

Research

Jump to: Review

20 pages, 4256 KiB  
Article
Clinical, Cortical, Subcortical, and White Matter Features of Right Temporal Variant FTD
by Jana Kleinerova, Mary Clare McKenna, Martha Finnegan, Asya Tacheva, Angela Garcia-Gallardo, Rayan Mohammed, Ee Ling Tan, Foteini Christidi, Orla Hardiman, Siobhan Hutchinson and Peter Bede
Brain Sci. 2024, 14(8), 806; https://doi.org/10.3390/brainsci14080806 - 11 Aug 2024
Viewed by 923
Abstract
The distinct clinical and radiological characteristics of right temporal variant FTD have only been recently recognized. Methods: Eight patients with right temporal variant FTD were prospectively recruited and underwent a standardised neuropsychological assessment, clinical MRI, and quantitative neuroimaging. Results: Our voxelwise grey analyses [...] Read more.
The distinct clinical and radiological characteristics of right temporal variant FTD have only been recently recognized. Methods: Eight patients with right temporal variant FTD were prospectively recruited and underwent a standardised neuropsychological assessment, clinical MRI, and quantitative neuroimaging. Results: Our voxelwise grey analyses captured bilateral anterior and mesial temporal grey matter atrophy with a clear right-sided predominance. Bilateral hippocampal involvement was also observed, as well as disease burden in the right insular and opercula regions. White matter integrity alterations were also bilateral in anterior temporal and sub-insular regions with a clear right-hemispheric predominance. Extra-temporal white matter alterations have also been observed in orbitofrontal and parietal regions. Significant bilateral but right-predominant thalamus, putamen, hippocampus, and amygdala atrophy was identified based on subcortical segmentation. The clinical profile of our patients was dominated by progressive indifference, decline in motivation, loss of interest in previously cherished activities, incremental social withdrawal, difficulty recognising people, progressive language deficits, increasingly rigid routines, and repetitive behaviours. Conclusions: Right temporal variant FTD has an insidious onset and may be mistaken for depression at symptom onset. It manifests in a combination of apathy, language, and behavioural features. Quantitative MR imaging captures a characteristic bilateral but right-predominant temporal imaging signature with extra-temporal frontal and parietal involvement. Full article
Show Figures

Figure 1

17 pages, 1454 KiB  
Article
Creatine Kinase and Respiratory Decline in Amyotrophic Lateral Sclerosis
by João Pedro Correia, Marta Gromicho, Ana Catarina Pronto-Laborinho, Miguel Oliveira Santos and Mamede de Carvalho
Brain Sci. 2024, 14(7), 661; https://doi.org/10.3390/brainsci14070661 - 28 Jun 2024
Viewed by 620
Abstract
Respiratory dysfunction is an important hallmark of amyotrophic lateral sclerosis (ALS). Elevation of creatine kinase (CK) has been reported in 23–75% of ALS patients, but the underlying mechanisms remain unknown. This work aims to enlighten the role of CK as a prognostic factor [...] Read more.
Respiratory dysfunction is an important hallmark of amyotrophic lateral sclerosis (ALS). Elevation of creatine kinase (CK) has been reported in 23–75% of ALS patients, but the underlying mechanisms remain unknown. This work aims to enlighten the role of CK as a prognostic factor of respiratory dysfunction in ALS. A retrospective analysis of demographic and clinical variables, CK, functional decline per month (ΔFS), forced vital capacity (%FVC), and mean amplitude of the phrenic nerve compound motor action potential (pCMAP) in 319 ALS patients was conducted. These measurements were evaluated at study entry, and patients were followed from the moment of first observation until death or last follow-up visit. High CK values were defined as above the 90th percentile (CK ≥ P90) adjusted to sex. We analyzed survival and time to non-invasive ventilation (NIV) as proxies for respiratory impairment. Linear regression analysis revealed that high CK was associated with male sex (p < 0.001), spinal onset (p = 0.018), and FVC ≥ 80% (p = 0.038). CK was 23.4% higher in spinal-onset ALS patients (p < 0.001). High CK levels were not linked with an increased risk of death (p = 0.334) in Cox multivariate regression analysis. CK ≥ P90 (HR = 1.001, p = 0.038), shorter disease duration (HR = 0.937, p < 0.001), lower pCMAP (HR = 0.082, p < 0.001), and higher ΔFS (HR = 1.968, p < 0.001) were risk factors for respiratory failure. The association between high CK levels and poorer respiratory outcomes could derive from cellular metabolic stress or a specific phenotype associated with faster respiratory decline. Our study suggests that CK measurement at diagnosis should be more extensively investigated as a possible marker of poor respiratory outcome in future studies, including a larger population of patients. Full article
Show Figures

Graphical abstract

Review

Jump to: Research

19 pages, 1609 KiB  
Review
Physiological Biomarkers of Upper Motor Neuron Dysfunction in ALS
by Aicee Dawn Calma, Mehdi van den Bos, Nathan Pavey, Cláudia Santos Silva, Parvathi Menon and Steve Vucic
Brain Sci. 2024, 14(8), 760; https://doi.org/10.3390/brainsci14080760 - 29 Jul 2024
Viewed by 813
Abstract
Upper motor neuron (UMN) dysfunction is an important feature of amyotrophic lateral sclerosis (ALS) for the diagnosis and understanding of pathogenesis. The identification of UMN signs forms the basis of ALS diagnosis, although may be difficult to discern, especially in the setting of [...] Read more.
Upper motor neuron (UMN) dysfunction is an important feature of amyotrophic lateral sclerosis (ALS) for the diagnosis and understanding of pathogenesis. The identification of UMN signs forms the basis of ALS diagnosis, although may be difficult to discern, especially in the setting of severe muscle weakness. Transcranial magnetic stimulation (TMS) techniques have yielded objective physiological biomarkers of UMN dysfunction in ALS, enabling the interrogation of cortical and subcortical neuronal networks with diagnostic, pathophysiological, and prognostic implications. Transcranial magnetic stimulation techniques have provided pertinent pathogenic insights and yielded novel diagnostic and prognostic biomarkers. Cortical hyperexcitability, as heralded by a reduction in short interval intracortical inhibition (SICI) and an increase in short interval intracortical facilitation (SICF), has been associated with lower motor neuron degeneration, patterns of disease evolution, as well as the development of specific ALS clinical features including the split hand phenomenon. Reduction in SICI has also emerged as a potential diagnostic aid in ALS. More recently, physiological distinct inhibitory and facilitatory cortical interneuronal circuits have been identified, which have been shown to contribute to ALS pathogenesis. The triple stimulation technique (TST) was shown to enhance the diagnostic utility of conventional TMS measures in detecting UMN dysfunction. Resting-state EEG is a novel neurophysiological technique developed for directly interrogating cortical neuronal networks in ALS, that have yielded potentially useful physiological biomarkers of UMN dysfunction. The present review discusses physiological biomarkers of UMN dysfunction in ALS, encompassing conventional and novel TMS techniques developed to interrogate the functional integrity of the corticomotoneuronal system, focusing on pathogenic, diagnostic, and prognostic utility. Full article
Show Figures

Graphical abstract

17 pages, 1705 KiB  
Review
Nanoplastics and Neurodegeneration in ALS
by Andrew Eisen, Erik P. Pioro, Stephen A. Goutman and Matthew C. Kiernan
Brain Sci. 2024, 14(5), 471; https://doi.org/10.3390/brainsci14050471 - 7 May 2024
Viewed by 2329
Abstract
Plastic production, which exceeds one million tons per year, is of global concern. The constituent low-density polymers enable spread over large distances and micro/nano particles (MNPLs) induce organ toxicity via digestion, inhalation, and skin contact. Particles have been documented in all human tissues [...] Read more.
Plastic production, which exceeds one million tons per year, is of global concern. The constituent low-density polymers enable spread over large distances and micro/nano particles (MNPLs) induce organ toxicity via digestion, inhalation, and skin contact. Particles have been documented in all human tissues including breast milk. MNPLs, especially weathered particles, can breach the blood–brain barrier, inducing neurotoxicity. This has been documented in non-human species, and in human-induced pluripotent stem cell lines. Within the brain, MNPLs initiate an inflammatory response with pro-inflammatory cytokine production, oxidative stress with generation of reactive oxygen species, and mitochondrial dysfunction. Glutamate and GABA neurotransmitter dysfunction also ensues with alteration of excitatory/inhibitory balance in favor of reduced inhibition and resultant neuro-excitation. Inflammation and cortical hyperexcitability are key abnormalities involved in the pathogenic cascade of amyotrophic lateral sclerosis (ALS) and are intricately related to the mislocalization and aggregation of TDP-43, a hallmark of ALS. Water and many foods contain MNPLs and in humans, ingestion is the main form of exposure. Digestion of plastics within the gut can alter their properties, rendering them more toxic, and they cause gut microbiome dysbiosis and a dysfunctional gut–brain axis. This is recognized as a trigger and/or aggravating factor for ALS. ALS is associated with a long (years or decades) preclinical period and neonates and infants are exposed to MNPLs through breast milk, milk substitutes, and toys. This endangers a time of intense neurogenesis and establishment of neuronal circuitry, setting the stage for development of neurodegeneration in later life. MNPL neurotoxicity should be considered as a yet unrecognized risk factor for ALS and related diseases. Full article
Show Figures

Figure 1

Back to TopTop