Search Results (1,887)

Neurodegenerative diseases (NDs), such as Alzheimer’s disease (AD), Parkinson’s disease (PD), Amyotrophic lateral sclerosis (ALS), and Huntington’s disease (HD), involve the gradual loss of structure or function of neurons in the nervous system and are an increasing threat to the aging population worldwide. Although these disorders have different clinical features which affect cognition, movement and other vital body functions, they share key underlying molecular and cellular processes. This starts with protein misfolding and aggregation, mitochondrial dysfunction, oxidative stress, dysregulated protein homeostasis, neuroinflammation, and disrupted cell death pathways. Recent findings have added disease-specific processes, like amyloid-β and tau aggregates in AD, α-synuclein aggregation and mitophagy failure in PD’s, TDP-43-related impaired RNA metabolism in ALS, and mutant huntingtin causing transcription aberrations in HD. Protein interactome network analysis showed mechanistic crosstalk between pathogenic proteins of AD and PD. New evidence highlights how lysosomal dysfunction, endoplasmic reticulum stress, and microglial activation, act as a common axis in neurodegeneration. Advancements in genomics and epigenomics have found shared genetic risk loci and regulatory processes that affect how diseases develop and progress. Simultaneously, new biomarkers like circulating microRNAs, exosome-related pathological proteins, neurofilament light chain, inflammatory cytokines, and microglial activation markers are powering early diagnosis tools and disease variations. New imaging techniques also allow for the identification of protein aggregations before symptoms appear. Overall, these findings are accelerating targeted treatments and personalized medicine aimed at disease progression. This review highlights current insights into the molecular mechanisms of NDs and discusses new biomarkers and treatment targets that help future diagnostic and treatment strategies. Full article

Vitamin D has long been recognized for its role in calcium homeostasis and bone metabolism; however, it is now emerging as an important regulator of central nervous system (CNS) function. Recent evidence suggests that vitamin D signaling contributes to the pathogenesis and progression of several neurodegenerative disorders. Vitamin D exerts neuroprotective effects through multiple mechanisms, including regulation of calcium homeostasis, modulation of immune responses, reduction in oxidative stress, stimulation of neurotrophic factors, and maintenance of blood–brain barrier (BBB) integrity. Vitamin D receptors and metabolizing enzymes are widely distributed across several brain regions, highlighting their direct involvement in neuronal function. This review summarizes the biosynthesis, metabolism, and signaling pathways of vitamin D. It explores its role in neurodegenerative diseases such as Alzheimer’s disease (AD), Parkinson’s disease (PD), multiple sclerosis (MS), amyotrophic lateral sclerosis (ALS), stroke, and traumatic brain injury (TBI). Evidence from experimental and clinical studies indicates that vitamin D deficiency is associated with an increased risk and severity of these conditions, while supplementation may provide therapeutic benefits. Full article

Neurodegenerative diseases are characterized by the accumulation of misfolded and aggregation-prone proteins, reflecting a failure of proteostasis. The ubiquitin–proteasome system (UPS), a major pathway for selective intracellular protein degradation, is essential for maintaining neuronal protein homeostasis. Proteasome dysfunction has been implicated in several major neurodegenerative disorders, including Alzheimer’s disease (AD), Parkinson’s disease (PD), amyotrophic lateral sclerosis (ALS), and Huntington’s disease (HD), although its extent and mechanisms vary across disease contexts. In this review, we examine current evidence for proteasome dysfunction in neurodegeneration and discuss how disease-associated proteins impair proteasome function through direct inhibition, defective substrate processing, and sequestration into protein aggregates. We also address the contribution of oxidative stress, neuroinflammation, and aging to proteasome dysregulation. Finally, we highlight emerging therapeutic strategies aimed at restoring proteasome function, including pharmacological activation, modulation of proteasome assembly and stability, and targeted protein degradation approaches. Understanding the context-dependent nature of proteasome dysfunction will be important for developing effective proteostasis-based therapies. Full article

Introduction: Vaccination against COVID-19 has been crucial in controlling the pandemic. While side effects are typically mild, rare neurological complications have been reported. This is a case series of ten patients who reported of persistent fasciculations after COVID-19 vaccination. Methods: We describe the clinical presentation and diagnostic work-up of ten patients with new-onset fasciculations in temporal proximity to COVID-19 vaccination. Patients with prior SARS-CoV-2 infection or known alternative causes of fasciculations were excluded. Routine clinical data, including neurological examination, laboratory results, and electrophysiology (electromyography and nerve conduction studies), were analyzed. Results: Ten patients (5 male, 5 female; mean age 42.4 years) reported fasciculations beginning within 6 h to 13 days post-vaccination and persisting for 2–12 months at the time of presentation. Fasciculations were accompanied by additional symptoms such as paresthesia and fatigue. Laboratory results were mostly unremarkable; two patients had positive myositis antibodies without clinical correlates. Electrophysiology was unremarkable in six patients, while fasciculation potentials were detected in four patients. Nine were diagnosed with probable benign fasciculation syndrome (BFS), and one met diagnostic criteria for amyotrophic lateral sclerosis (ALS). Discussion: In this small, retrospective case series, most cases of post-vaccination fasciculations were benign and compatible with BFS. Whether BFS onset was causally linked to vaccination or due to a nocebo effect remains unclear. One patient was diagnosed with ALS, though a causal link remains speculative given the study’s limitations and rarity of similar reports. Larger, prospective studies are needed to validate these observations and explore underlying pathophysiological mechanisms. Full article

The GGGGCC hexanucleotide repeat expansion (HRE) in C9ORF72 was recognized as the most common genetic cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). Repeat-associated non-AUG (RAN) translation of the expanded repeat generated dipeptide repeat proteins (DPRs), which disrupted multiple cellular processes and contributed to neurodegeneration. Emerging evidence indicated that disease pathogenesis involved both gain-of-function (GOF) and loss-of-function (LOF) mechanisms. DPR-mediated GOF toxicity induced ribosomal dysfunction, nucleolar stress, proteostatic impairment, and neuronal injury, whereas C9ORF72 LOF disrupted lysosomal and autophagic pathways in microglia, impairing the immune homeostasis. Neuronal injury further promoted the release of damage-associated signals that triggered secondary microglial activations and chronic neuroinflammations. This review summarized current knowledge of DPR biology, microglial dysfunction, and their contributions to disease progression in C9ORF72-associated ALS/FTD. Therapeutic strategies targeting repeated RNA, DPR productions, proteostasis, autophagy, and neuroinflammatory pathways were also discussed. In addition, the potentials of fluid biomarkers, including cerebrospinal fluid poly (GP) and blood neurofilament light chain (NfL), for diagnosis, disease monitoring, and therapeutic assessment were shown. Together, these findings provided important insights into disease mechanisms and potential avenues for improved clinical management. Full article

Patients with neurodegenerative diseases such as amyotrophic lateral sclerosis (ALS) frequently lose the ability to communicate through speech or writing. However, their cognitive and sensory functions are often relatively preserved. In Japan, the traditional method known as kuchimoji (mouth-based character communication) enables character-by-character communication using mouth shapes. This method relies heavily on caregiver skill and is challenging to implement consistently. This study introduces KUCHIMOJI, a Japanese text input system that uses mouth-shape recognition to support independent augmentative and alternative communication (AAC) without caregiver assistance. The system employs a lightweight convolutional neural network (MobileNetV2) to classify six mouth shapes. These shapes correspond to five vowels and a closed-lip state. To accommodate diverse user conditions, a multimodal input framework is designed. It supports three operation modes: facial-image-based signal input, button-based input, and key-based direct input. As an initial feasibility study, experiments with ten healthy participants were conducted to evaluate text entry performance in terms of text entry speed (TES) and miss entry rate (MER). Results indicate that the system achieves average input speeds of 3.86, 5.32, and 11.35 characters per minute (cpm) for the facial-image, button, and key-based modes, respectively. It maintains low error rates (2.96–5.05%). These findings suggest that the system offers a flexible trade-off between speed and accuracy depending on the input modality. The proposed approach provides a practical, low-cost, non-contact communication solution. This underscores its potential forpractical assistive communication applications. Full article

Amyotrophic lateral sclerosis (ALS) remains an intractable motor neuron (MN) disease with a growing patient population and few effective treatments. Here, we review how extracellular phosphoglycerate kinase 1 (ePgk1) improves neurite outgrowth of MNs (NOMN) and axonal growth, both in vitro and in vivo. Our group first elucidated a novel non-canonical function of ePgk1 as a cross-tissue mediator between nerve and muscle tissues. We then discovered that neural membranous Enolase 2 (Eno2) serves as a receptor of ligand ePgk1 and that ePgk1-Eno2 interaction suppresses the Rac1-GTP/p-Pak1-T423/p-P38-T180/pMK2-T334/p-Limk1-S323 axis, reducing p-Cofilin and promoting NOMN and axonal growth, finally suggesting that the 419th aspartic acid residue of Eno2 mediates this interaction. In a crucial preclinical step, we truncated two short 16-amino-acid derivatives from Pgk1, FD-1/-2, each mediating neuroprotection comparable to that of full-length 417-amino-acid Pgk1 in ALS animal models, in terms of improvements of innervated neuromuscular junction, MN cell bodies, motor performance, and endpoint prolongation. In this context, we also discuss the opposite function driven by Eno1-plasminogen interaction and by Eno2-ePgk1 interaction; the latter results in unfavorable for tumorigenesis. Unlike intracellular Pgk1 roles, ePgk1 is an extracellular factor with anti-angiogenic properties, further positioning ePgk1 and its FD-1/-2 as promising protein/peptide drugs for ALS treatment. Full article

Motoneurons are under strong pressure to maintain stable motor output throughout an individual life, through homeostatic regulation of their electrical properties. Dysregulated spinal motoneuron excitability has long been implicated in the pathogenesis of amyotrophic lateral sclerosis (ALS). Recent work in SOD1^G93A mice suggests that the homeostatic response of motoneurons becomes dysregulated as cellular processes are disrupted by the disease, causing fluctuations in motoneuron electrical properties. Yet, few studies directly test whether ALS motoneurons respond differently than wild-type motoneurons to a common chronic perturbation. Here, we used in vivo electrophysiology to test whether motoneurons from pre-symptomatic SOD1^G93A mice modulate excitability differently than wild-type motoneurons in response to the same homeostatic perturbation: chronic inhibition exerted by the benzodiazepine diazepam. Using linear mixed-effects statistical models, we assessed whether diazepam treatment differentially modulated passive properties, firing behavior, spike properties, and/or synaptic inputs in SOD1^G93A versus wild-type motoneurons. We identified a significant genotype × treatment interaction effect selectively for properties related to passive membrane integration and spike initiation, including membrane time constant, peak input resistance, and recruitment current. In contrast, firing gain, spike waveform characteristics, and synaptic inputs were largely unaffected. These findings indicate that sustained inhibitory perturbation selectively triggered overactive intrinsic compensatory mechanisms in SOD1^G93A motoneurons rather than inducing widespread changes in firing or synaptic transmission. Together, our results provide direct evidence for over-active homeostatic control of motoneuron excitability and support a view of motoneuron dysfunction in ALS as a problem of altered feedback regulation rather than simply hyper- or hypo-excitability. Full article

Neuroinflammation plays a central role in the onset and progression of neurodegenerative disorders. Several disease-modifying therapies have been developed to target neuroinflammatory pathways in specific disorders. However, their ability to stop disease progression or restore neuronal and mitochondrial homeostasis remains limited. This is still a major unmet clinical need. In this context, mesenchymal stromal cell (MSC)-derived Extracellular Vesicles (EVs) have emerged as a promising cell-free therapeutic strategy due to their ability to modulate immune responses and promote neuroprotection through the delivery of bioactive cargo. Recent evidence has identified a distinct subset of EVs, known as mitochondrial EVs (mito-EVs), which carry mitochondrial DNA, proteins, and functional components. These vesicles may uniquely influence cellular bioenergetics, redox balance, and neuroinflammatory signaling, offering additional therapeutic potential compared to conventional MSC-EVs. This review summarizes the role of MSC-derived EVs in neuroinflammatory disorders, with a particular focus on mito-EVs. It also discusses preconditioning strategies to enhance EV efficacy, including hypoxic, inflammatory, pharmacological priming and genetic engineering approaches. Finally, we critically evaluate current preclinical evidence regarding the treatment of major neurodegenerative disorders, including Alzheimer’s disease, Parkinson’s disease, Multiple Sclerosis, and Amyotrophic Lateral Sclerosis, as well as Traumatic Injury, highlighting the key challenges for clinical translation. Full article

Extracellular vesicles (EVs) have emerged as key mediators of intercellular communication in the brain, with glial cell-derived EVs increasingly recognized for their roles in maintaining brain homeostasis and contributing to the progression of neurodegenerative diseases. By transferring a diverse cargo of bioactive molecules, including proteins, RNAs, and organelles, EVs influence recipient cell behavior and overall brain function. In neurodegenerative conditions, glial EVs can either propagate pathogenic signals or deliver neuroprotective and regenerative cues, depending on their cellular origin and molecular composition. This context-dependent heterogeneity highlights the need for physiologically relevant human models to investigate EVs biology. Human induced pluripotent stem cell (iPSC)-derived glial models provide a disease-relevant platform, as they recapitulate key pathological features of Alzheimer’s disease (AD), Parkinson’s disease (PD) and amyotrophic lateral sclerosis (ALS). When further integrated with brain organoid platforms, these iPSC-based systems enable the generation of three-dimensional environments that closely resemble in vivo EVs dynamics. Importantly, glial EVs can modulate cellular pathways involved in neuronal survival and function. Indeed, their potential to interact with and, under specific experimental conditions, traverse the blood–brain barrier (BBB) has contributed to growing interest in their application for biomarker discovery and therapeutic development. Engineered and patient-specific EVs derived from iPSCs are emerging as promising tools for targeted, cell type-specific, therapeutic approaches, although their clinical applicability still requires further validation. This review discusses the emerging evidence supporting the dual role of iPSC-derived glial EVs in health and disease, underscores the translational potential of iPSC-based platforms for mechanistic studies, and outlines their promise as precision medicine tools for diagnostics and therapy. Full article

RNA-binding proteins (RBPs) are essential regulators of all aspects of RNA metabolism, including splicing, stability, localisation, translation, and degradation. Through their ability to recognise specific cis-elements in target transcripts, often via RNA-recognition motifs or other conserved domains, RBPs enable rapid cellular adaptation to stress and maintain proteostasis, particularly in post-mitotic tissues with limited transcriptional flexibility. Accumulating evidence positions RBPs as both modulators and drivers of the molecular hallmarks of ageing, including genomic instability, loss of proteostasis, mitochondrial dysfunction, cellular senescence, and chronic inflammation. This review synthesises peer-reviewed studies on the multifaceted roles of RNA-binding proteins in organismal ageing and age-related diseases. Key themes include the tissue- and age-dependent changes in expression of turnover and translation regulatory RBPs such as HuR (ELAVL1), AUF1 (HNRNPD), TIA-1, and tristetraprolin (ZFP36), which alter the stability of mRNAs encoding cell-cycle regulators, pro-inflammatory cytokines, and stress-response proteins. Systematic downregulation of core splicing factors, including PTBP1 and several heterogeneous nuclear ribonucleoproteins, drives widespread senescence-associated splicing alterations in pathways governing cell division, autophagy, DNA repair, and mitochondrial function, suggesting a causal contribution to the senescent phenotype. Prion-like RBPs such as TDP-43 and FUS exhibit age-dependent mislocalisation, nuclear depletion, and cytoplasmic aggregation, contributing to splicing defects, impaired RNA transport, and neurodegeneration in amyotrophic lateral sclerosis, frontotemporal dementia, and limbic-predominant age-related TDP-43 encephalopathy. Interactions between RBPs and non-coding RNAs, together with disrupted liquid–liquid phase separation dynamics, further exacerbate age-related decline. By integrating mechanistic studies from cellular and animal models with observations in human cohorts, this review underscores RBPs as central nodes linking multiple ageing hallmarks and highlights their potential as biomarkers and therapeutic targets to promote healthy ageing. Limitations of current models and priorities for future translational research are discussed. Full article

Cell replacement therapy is a promising investigational approach for Parkinson’s disease (PD), a neurodegenerative disorder characterized by progressive loss of dopaminergic neurons in the substantia nigra. Although current PD therapies provide symptomatic relief, none halt or reverse disease progression. Early transplantation studies using fetal dopaminergic neurons provided proof of concept for PD cell replacement, with recent efforts focusing on pluripotent stem cell-derived dopaminergic progenitors that are now entering clinical testing. These strategies face challenges, however, including immune compatibility, tumorigenic risk, and the need for controlled differentiation and functional integration. Multi-lineage differentiating stress-enduring (Muse) cells are endogenous, non-tumorigenic pluripotent-like stem cells that home to sites of tissue injury and differentiate in response to the host microenvironment. A targeted literature search of PubMed and Scopus, however, did not identify prior reviews specifically addressing Muse cells in the context of PD, highlighting a gap in the literature. Here, we examine current limitations of established cell-replacement approaches and consider whether Muse cells may represent a mechanistically distinct cell source. Early clinical studies of Muse cell therapy in stroke and amyotrophic lateral sclerosis suggest an encouraging safety profile and preliminary signals of potential therapeutic benefit, although these findings are based on small, early-stage trials and require confirmation. The evidence supporting Muse cell therapy in PD is currently limited to a single preclinical animal study, supported by mechanistic in vitro findings and indirect evidence from other neurologic disease models; therefore, its relevance to PD remains to be established, and current evidence is insufficient to support conclusions regarding clinical efficacy. Together, these observations provide a rationale for further targeted preclinical investigation and support the systematic evaluation of Muse cells as a mechanistically distinct candidate for regenerative therapy in PD. Full article

Background/Objectives: Spirituality is increasingly recognised as a core dimension of holistic and palliative care. Neurodegenerative diseases such as dementia, amyotrophic lateral sclerosis and Parkinson’s disease involve prolonged trajectories of loss, uncertainty and relational change, which may heighten spiritual and existential needs for patients, particularly among those involved in caregiving, such as family caregivers and, to a lesser extent, healthcare professionals. However, evidence on how spirituality is understood, experienced and addressed within neurodegenerative palliative care remains fragmented and conceptually heterogeneous. This scoping review aimed to map the literature on caregivers’ spiritual needs and challenges. Methods: A scoping review was conducted in accordance with the Joanna Briggs Institute (JBI) methodology for scoping reviews and the Preferred Reporting Items for Systematic Reviews and Meta Analyses extension for Scoping Reviews (PRISMA ScR). Searches were conducted across PubMed, Cumulative Index to Nursing and Allied Health Literature (CINAHL), APA PsycINFO, and Scopus, with no date or geographical restrictions. Grey literature was searched through Google Scholar and relevant organisational and policy sources in the field of palliative care and spirituality. Reference list screening of included studies and relevant reviews was also conducted. Quantitative, qualitative, and mixed methods studies published in English or Italian were included. Results: Twenty-four studies published between 2007 and 2025 were included. Findings were organised into three interconnected domains: spiritual needs, spiritual processes and spiritual care. Spirituality emerged as a dynamic, relational and context-dependent dimension of caregiving, encompassing meaning, identity, connection and coping with vulnerability and loss. Spiritual needs and processes were widely described, while spiritual care was inconsistently recognised within healthcare systems. Conceptual ambiguity, under-representation of end-of-life dementia and cultural imbalances were evident. The evidence predominantly focused on family caregivers, with limited representation of healthcare professionals. Conclusions: This scoping review highlights a persistent gap between caregivers’ lived spiritual experiences and system-level responses in neurodegenerative palliative care in caregiving contexts globally. The findings support integrated, caregiver-inclusive and culturally responsive approaches to spiritual care. Full article

Iron is an essential micronutrient that plays a central role in numerous biological processes. Despite its relatively low abundance in the human body, iron is particularly critical for brain function. Systemic and cerebral iron homeostasis is tightly regulated through coordinated mechanisms involving absorption, transport, storage, and recycling. Within the brain, iron metabolism is further controlled by the blood–brain barrier and specialized neural cell populations, including neurons, astrocytes, oligodendrocytes, and microglia. Iron is indispensable for neurodevelopment, supporting neurogenesis, myelination, and neurotransmitter synthesis. However, both iron deficiency and iron overload have detrimental consequences. Early-life iron deficiency disrupts neural development and leads to long-lasting cognitive, motor, and behavioral impairments, whereas excessive iron accumulation promotes oxidative stress, ferroptosis, and neuroinflammation. These mechanisms have been described to contribute to the pathogenesis of major neurodegenerative disorders, including Alzheimer’s disease, Parkinson’s disease, neurodegeneration with brain iron accumulation, and amyotrophic lateral sclerosis. This review first outlines systemic and brain iron metabolism, highlighting how neural cells regulate homeostasis. Next, it examines iron’s physiological roles, particularly in neurogenesis and neurodevelopment. Finally, it explores iron’s involvement in neurodegenerative diseases, emphasizing neuroinflammation as a primary mechanism of iron toxicity. Full article

Background and Objectives: Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease frequently associated with dysphagia and aspiration risk. This study aimed to investigate the relationship between clinical dysphagia assessment tools (EAT-10, GUSS, RSST, and sialorrhea severity) and videofluoroscopic swallowing study (VFSS) findings in patients with ALS. Materials and Methods: This retrospective observational study included 60 patients with ALS classified as spinal-onset (n = 38) or bulbar-onset (n = 22). Relationships between clinical assessments and VFSS findings were analysed using Spearman correlation analysis. Exploratory multivariable regression and receiver operating characteristic (ROC) analyses were performed to evaluate associations and aspiration risk discrimination. Results: Strong negative correlations were observed between PAS–Liquid and RSST and GUSS scores, whereas EAT-10 showed a strong positive correlation (all p < 0.001). ROC analyses demonstrated good discriminative ability for aspiration risk for GUSS (AUC = 0.89), RSST (AUC = 0.88), and EAT-10 (AUC = 0.82). Patients with bulbar-onset ALS demonstrated higher penetration–aspiration severity and lower functional oral intake. Conclusions: Clinical dysphagia assessment tools showed significant associations with instrumental swallowing findings in ALS. GUSS and RSST demonstrated good discriminative ability for aspiration risk and may be clinically useful bedside screening tools. However, instrumental swallowing assessment remains essential whenever feasible. Full article