Search Results (480)

Parkinson’s disease (PD) is a neurodegenerative disorder characterized by the aggregation of Lewy bodies, composed of the protein α-synuclein, and the degeneration of dopaminergic (DA) neurons in the substantia nigra pars compacta. The management of PD seeks to mitigate motor symptoms by substituting diminished endogenous dopamine; nevertheless, it does not halt disease progression. Various animal models have been employed to elucidate the etiology of PD and to discover disease-modifying treatments. Zebrafish serve as a PD model owing to their capacity for high-throughput screening. This review presents updates on the currently available zebrafish models of PD, encompassing both chemically induced and genetically based models, and discusses their advantages and limitations. This review also delineates numerous investigative strategies that utilize the zebrafish PD model and summarizes the findings of previous studies. Taken together, further studies, including the investigation of the regeneration mechanism of DA neurons, neurobehavioral testing of adult zebrafish reflecting PD-associated neurocognitive impairment, and a reliable gene-based model providing precise gene knockout and reproducibility, may assist in elucidating the critical pathways that trigger PD and its progression, alongside potential targets to hinder this progression. Full article

Neuromuscular and neurodegenerative (NMND) disorders are diseases that cause progressive damage to the central nervous system leaving patients with symptoms that negatively affect everyday living with death almost inevitable. These include amyotrophic lateral sclerosis (ALS), Lewy body dementia (LBD), and Parkinson’s disease (PD) with cases expected to increase in the future. Intranasally administered stem cell-derived exosomes/secretome have been seen as potential therapeutic options for these disorders in preclinical animal models. This study sought to observe the efficacy of mesenchymal stem cell-derived exosomes/secretome in patients with ALS, LBD, and PD. Based off these preclinical studies, we conducted a case-controlled series experiment with 86 patients with ALS, LBD, or PD, with the independent variable being the treatment and the dependent variable being the clinical response. These patients were recruited and given intranasal instillations of various MSC-derived exosome/secretome products. Subsequent treatments were given to patients who did not have a response to one product. Patients were followed up at one week, one, two, three, and six months post-treatment. Historical external controls were used for comparison to clinical outcomes. There were no serious adverse events in any patient. A total of 67 of 86 (77%) patients showed a positive clinical response to at least one product. Outcomes were strongly associated with greater treatment frequency for ALS and LBD. Intranasal administration of MSC-derived exosome/secretome products were safe, and most patients showed overall improvement with at least one product. Some patients also saw a substantial decrease in the rate of decline compared to historical controls. These results also give rise to the hypothesis: do MSC-derived exosomes/secretome treatments show efficacy in other NMND disorders? The primary limitation of this study is the 6-month follow-up. Full article

Neurodegenerative diseases are among the most consequential disorders of later life, not only because of their increasing prevalence, rising from approximately 1–2% at age 65 to over 30% by age 85, but also because they develop within the broader clinical context of ageing, multimorbidity, frailty, and polypharmacy. In older adults, these conditions rarely present as isolated and static diagnostic entities; rather, they unfold as dynamic clinical trajectories involving the progressive interaction of cognitive decline, behavioural-neuropsychiatric symptoms, and extrapyramidal-motor dysfunction. In this review, we propose a trajectory-based framework for the interpretation and management of major neurodegenerative disorders in later life, including Alzheimer’s disease, frontotemporal dementia, Parkinson’s disease and Parkinson’s disease dementia, dementia with Lewy bodies, and vascular cognitive impairment. Building on a conceptual model organized around three major symptom spheres: cognitive, behavioural-neuropsychiatric, and extrapyramidal-motor, we argue that each disorder can be understood according to the relative predominance and temporal evolution of these domains. Alzheimer’s disease is typically cognition-led, frontotemporal dementia behaviour-led, and Parkinsonian syndromes motor-led, whereas dementia with Lewy bodies shows early multidomain convergence across all three spheres simultaneously. Vascular and mixed dementias follow more heterogeneous trajectories shaped by lesion burden, network disruption, and copathology. This framework has direct implications for diagnosis, prognostic stratification, and treatment selection, because interventions targeting one sphere may destabilize another and generate prescription cascades, delirium, or functional decline. We further discuss how biomarker-based diagnosis, disease-modifying therapies, non-pharmacological interventions, multidisciplinary care, deprescribing strategies, and palliative planning can be integrated within a trajectory-based approach. Interpreting neurodegeneration through clinical trajectories rather than diagnostic labels alone offers a more realistic and therapeutically useful model for precision geriatric neurology across the full course of disease. Full article

Background/Objectives: The evaluation of cognition is central to many neurological conditions, including traumatic brain injury, Alzheimer’s disease, Lewy body disease, frontotemporal degeneration, and vascular disorders. In clinical practice, particularly in aging populations, cognitive complaints often arise in the context of mixed neurological processes, requiring careful integration of cognitive and non-cognitive findings. Despite this, there remains limited clarity regarding the respective roles of neurologists and clinical neuropsychologists and the distinction between cognitive and neuropsychological assessments, terms that are often used interchangeably despite important differences in methodology and scope. This lack of a shared framework has practical consequences. Cognitive test results, when interpreted in isolation for diagnosis, may be misconstrued as comprehensive measures of brain function, particularly when non-cognitive neurological features such as motor, cerebellar, or vestibular abnormalities should have been considered (but were not). Methods: In this narrative review, we synthesize clinical guidelines, consensus statements, regulatory sources, and representative empirical literature to articulate a competence-based framework in which cognitive assessment is a medically integrated process incorporating history, functional evaluation, neurological examination, and the targeted use of standardized neuropsychological instruments. Results: Neurologists are trained to establish medical diagnoses and integrate cognitive findings into the context of neurological disease, while neuropsychologists contribute detailed psychometric characterization, culturally and demographically informed interpretation, cognitive phenotyping, functional characterization, and validity assessment in complex clinical and medicolegal contexts. Although neuropsychologists are qualified to diagnose neurocognitive disorders using standardized diagnostic criteria, attribution to specific neurological etiologies requires a comprehensive medical evaluation that extends beyond cognitive testing alone. Conclusions: We outline a tiered approach to evaluation that aligns assessment methods with clinical questions and supports accurate diagnosis, interdisciplinary collaboration, and patient-centered care. Full article

Parkinson’s disease (PD) is a prevalent neurodegenerative disorder, characterized by the loss of dopaminergic neurons in the substantia nigra pars compacta and the accumulation of Lewy bodies. Over recent decades, various cellular mechanisms underlying PD have been elucidated, including autophagy, mitochondrial dysfunction, neuroinflammation, and axonal transport. Among them, axonal transport plays a critical role in maintaining the dynamic homeostasis of proteins, membrane-bound organelles, and cellular metabolism within neurons. Unfortunately, a comprehensive overview of axonal transport in PD remains absent. In this review, we synthesized the current literature on axonal transport in PD, leveraging neurotoxic and genetic models to explore the causes and consequences of axonal transport alterations in PD. Through this summary, we aim to deepen our understanding of PD pathogenesis and provide potential therapeutic targets for intervention. Full article

Psychotic symptoms, including delusions and hallucinations, frequently complicate the course of Alzheimer’s disease (AD), dementia with Lewy bodies (DLB), Parkinson’s disease dementia (PDD), and frontotemporal dementia (FTD). Their presence accelerates decline, worsens outcomes, and complicates management. Cognitive screening in such patients is essential yet challenging due to attentional fluctuation, impaired insight, and diagnostic overlap. Addenbrooke’s Cognitive Examination III (ACE-III) is a multidomain tool with higher sensitivity than the MMSE. Evidence indicates that ACE-III captures disorder-specific cognitive-psychotic profiles: memory impairment in AD with delusions of theft, visuospatial and attentional deficits in DLB with hallucinations, or executive dysfunction in FTD with paranoid ideation. Mini-ACE (M-ACE), a shorter derivative, is useful in acute psychiatric or advanced dementia settings. This review synthesizes evidence on ACE-III and M-ACE in psychosis-related neurodegeneration, highlights their role in differentiating from primary psychiatric psychoses, and identifies knowledge gaps, particularly in atypical AD variants, mixed dementia, and autosomal dominant AD. ACE-III emerges as a practical and informative tool, but psychosis-specific normative data and longitudinal studies are needed. Full article

Synucleinopathies, including Parkinson’s disease and dementia with Lewy bodies, are characterized by progressive α-synuclein (α-Syn) aggregation accompanied by chronic neuroinflammatory changes. However, the mechanistic relationship between disrupted proteostasis and inflammatory signaling remains incompletely defined and may vary across disease stages and clinical subtypes. Lysophospholipids (LPLs) are bioactive lipids derived from membrane phospholipids that participate in diverse cellular processes. These functions are primarily mediated through G protein-coupled receptor (GPCR) signaling, but may also involve direct effects on membrane organization and biophysical properties. In addition to receptor-mediated pathways, the surrounding lipid environment may influence protein behavior, although its role in neurodegenerative processes remains to be fully elucidated. Within this framework, LPLs can be considered not only as signaling molecules but also as modulators of the cellular environment in which proteostasis and inflammatory responses occur. In this review, we adopt a lipid-centered perspective in which LPLs occupy an interface between lipid signaling, protein aggregation, and neuroinflammation. Rather than acting as a single initiating factor, altered lipid metabolism is likely to contribute through multiple interconnected pathways. Although current evidence is largely derived from preclinical studies, it supports a role for lipid-related mechanisms, particularly in early stages of synucleinopathy. Full article

Vascular dementia (VaD) is a type of dementia caused by cerebrovascular factors, which can arise from both ischemic cerebrovascular disease and hemorrhagic cerebrovascular disease. The incidence rate of VaD is second only to Alzheimer’s disease and dementia with Lewy bodies. Currently, there are no effective drugs specifically targeting VaD, making the discovery of new therapeutic targets of great significance. This article provides an overview of the research progress on VaD, with a focus on elucidating its pathogenesis, aiming to identify targets that play a regulatory role in the mechanism. Finally, our attention is drawn to the transcription factor E2F1. Through research, it has been found that E2F1 is involved in biological processes such as cell cycle regulation and apoptosis and plays a certain role in neurodegenerative diseases and ischemic encephalopathy. It also participates in the pathogenesis of vascular dementia, suggesting that E2F1 is a key regulatory molecule for VaD and may become a potential pharmacological therapeutic target, which warrants further in-depth research. Full article

Atypical Parkinsonisms are a diverse group of diseases associated with multiple pathologies, including synucleinopathies and tauopathies. Atypical Parkinsonisms include progressive supranuclear palsy, corticobasal degeneration, multiple system atrophy, and dementia with Lewy bodies. The examination of these diseases is complicated due to their overlapping clinical manifestations. Hence, tools enabling reliable supplementary assessment of atypical Parkinsonisms are needed. The most common methods involve neuroimaging; however, these evaluations generally involve basic magnetic resonance imaging and indicate possible morphological changes. Less attention is given to disease background assessment. Biochemical assessment enables a more detailed examination of the factors impacting neurodegenerative processes. The features that may impact the pathophysiology of these diseases include metabolic abnormalities, excessive inflammation, and environmental factors. In this context, proteomic evaluation, as analyzed in this article, could partly address the insufficiently described aspects of the unclear pathological mechanisms related to atypical Parkinsonisms. Full article

Neurodegenerative diseases, including Alzheimer’s Disease (AD), Parkinson’s Disease (PD), Lewy Body Disease (LBD), and related dementias, represent a global health challenge, particularly in aging populations. The simultaneous occurrence of neurodegenerative diseases in an aging population suggests a potential link between causative proteins. Such neurodegenerative proteins, including amyloid-β (Aβ), τ-protein (tau), α-synuclein, TAR DNA-binding protein 43 (TDP-43), and Fused in Sarcoma (FUS), share key characteristics of intrinsically disordered proteins (IDPs), which can explain promiscuous physical interactions, cross-seeding, co-occurrence, pathological synergy, and shared upstream and downstream mechanisms. This review synthesizes current evidence on (1) shared biophysical features of neurodegeneration-associated proteins, (2) mechanisms driving mixed neuropathology, (3) therapeutic implications of disorder-driven interactions, and (4) key unresolved questions shaping future research. By framing neurodegeneration as a network of interacting, disorder-driven proteinopathies rather than isolated entities, this perspective highlights the need for integrative, systems-level approaches to better understand disease heterogeneity and to identify novel targets for intervention. Full article

Parkinson’s disease (PD) is a common neurodegenerative disorder marked by progressive loss of dopaminergic neurons in the substantia nigra pars compacta and the accumulation of Lewy bodies, intracellular inclusions enriched in α-synuclein. Synphilin-1 interacts with α-synuclein, localizes to Lewy bodies, and has been implicated in inclusion formation and neuroprotection in cellular and animal models; however, its physiological function in vivo remains poorly defined. Here, we generated and characterized a synphilin-1 knockout (Sph-1 KO) mouse by targeted genetic deletion of the Sph-1 locus and performed a comprehensive phenotyping battery including behavioral testing as well as biochemical, histological, structural, and ultrastructural analyses. Sph-1 KO mice survived to nearly two years of age and showed normal body weight, lifespan, motor performance, learning and memory, anxiety-like behavior, attention, and gross brain morphology. Western blot analyses indicated that levels of α-synuclein and synaptic proteins were largely unchanged. While outer mitochondrial membrane proteins were unaffected, the mitochondrial matrix protein HSP60 was reduced, consistent with altered mitochondrial proteostasis in the absence of synphilin-1. Strikingly, histochemical analyses, magnetic resonance imaging, and electron microscopy revealed early-onset hydrocephalus in Sph-1 KO mice associated with severe loss and disorganization of motile ependymal cilia in the ventricular lining, a cell type that normally expresses high levels of synphilin-1. Ultrastructural and immunohistochemical analyses revealed disrupted ependymal architecture, mislocalization of acetylated α-tubulin to the cytoplasm, cellular swelling, and enlarged, aberrant mitochondria, whereas cortical neurons appeared largely structurally unaffected. Together, these findings identify synphilin-1 as a key regulator of microtubule organization and cytoskeletal/organelle homeostasis in ependymal cells, required to maintain motile ciliogenesis, cerebrospinal fluid flow, and ventricular integrity. This unexpected role for synphilin-1 in ciliated brain epithelia, along with a reduction in the critical mitochondrial chaperone HSP60, broadens our understanding of synphilin-1 biology and provides a new framework for its potential relevance to PD-associated pathology. Full article

Background and Objectives: Parkinson’s disease (PD) entails the progressive degeneration of dopaminergic neurons in the substantia nigra (SN), accompanied by α-synuclein (α-syn)-enriched Lewy bodies. ITGA7 mediates cell–extracellular matrix adhesion and modulates apoptosis, though its involvement in PD pathogenesis warrants further investigation. Although acupuncture demonstrates neuroprotective effects in PD models, its precise molecular mechanisms remain incompletely understood; therefore, in this study, we explored the relationship between ITGA7 and α-synuclein expression in an MPTP-induced PD mouse model to determine the association between LR3/GB34 acupuncture-induced changes in α-synuclein levels and ITGA7 modulation. Materials and Methods: In the in vivo model, MPTP-induced PD mice underwent immunohistochemistry, immunofluorescence, and Western blotting to assess ITGA7, α-synuclein, and TH levels in the SN and striatal tissues following LR3/GB34 acupuncture. In parallel, for the in vitro mechanistic study, SH-SY5Y neuroblastoma cells treated with MPP⁺ and transfected with ITGA7-siRNA were utilized to examine the involvement of apoptosis-related signaling pathways. Results: In the in vivo model, MPTP administration downregulated ITGA7 and upregulated α-synuclein in SN tissues. Similarly, in vitro exposure of SH-SY5Y cells to MPP⁺ yielded comparable results, revealing an inverse correlation between ITGA7 and α-synuclein. LR3/GB34 acupuncture treatment in the mouse model significantly increased ITGA7 and TH expression while reducing α-synuclein accumulation. To further understand the specific role of ITGA7 observed in these animal findings, we silenced ITGA7 in the MPP⁺-treated cellular model. ITGA7 silencing exacerbated the neurotoxic effects, leading to further TH downregulation, α-synuclein upregulation, Bcl-2 reduction, and Bax/Bcl-2 ratio elevation. Conclusions: Collectively, the histological preservation of dopaminergic neurons following LR3/GB34 acupuncture in the PD mouse model appears to be linked to ITGA7 upregulation. Furthermore, our in vitro findings implicate ITGA7 in the regulation of apoptosis-related signaling cascades, supporting its potential role in mitigating α-synuclein pathology. Full article

Neurodegenerative diseases feature diverse pathological protein aggregates, including Lewy bodies in Alzheimer’s disease (AD) and skein-like filaments in amyotrophic lateral sclerosis (ALS). The physical mechanisms underlying this morphological diversity remain unclear. Here, we demonstrate that aggregation of the prion-like domain of hnRNPA1 (A1PrD), implicated in AD and ALS, is driven by solution composition and phase transition dynamics. Utilizing 3D timelapse and fluorescence lifetime imaging microscopy, we show that solution conditions modulate phase separation, gelation, and fibrillation, resulting in distinct structures such as fibril, gel, and starburst morphologies. Homotypic and heterotypic interactions between A1PrD and RNA were observed to shift the balance between pathological and physiological condensates. Importantly, amyloid-rich starbursts displayed prion-like infection capabilities toward amyloid-poor condensates. Our findings highlight how the interplay between solution composition and kinetic balances of liquid-liquid phase separation, gelation, and fibrillation shapes the diverse pathological aggregate morphologies characteristic of neurodegenerative diseases. Full article

The Benson Complex Figure Test (BCFT) is a neuropsychological tool designed to assess visuospatial construction and visual memory with lower complexity than traditional tests. This study evaluated its ability to differentiate between major dementia subtypes. In a retrospective cross-sectional analysis of 1428 participants from a Greek third-age day center (healthy participants [Controls]; patients diagnosed with Alzheimer’s disease dementia [ADD], Lewy body dementia [LBD], Frontotemporal dementia [FTD: behavioral variant (BV), non-fluent variant (NFV), semantic variant (SV)], Corticobasal dementia [CBD], Parkinson’s disease dementia [PDD], and mixed Cardiovascular dementia with Alzheimer’s disease [CVD/AD]), all participants completed the BCFT and the Mini-Mental State Examination (MMSE). Multinomial logistic regression, adjusted for age, sex, and education, revealed distinct BCFT profiles across dementia subtypes. Patients with CBD showed significantly lower copy scores than those with ADD (p = 0.006). The FTD-NFV group exhibited superior memory scores compared to all other dementia subtypes (p < 0.001). Poorer BCFT recognition performance was strongly associated with diagnoses of ADD (OR = 0.39, p = 0.012), FTD-BV (OR = 0.22, p = 0.025), and PDD (OR = 0.26, p < 0.001). Classification accuracy was highest for controls and ADD (sensitivity > 89%) but low for rarer subtypes (<25%), partly reflecting sample size limitations. In conclusion, the BCFT captures distinct visuospatial and memory profiles across dementia syndromes, supporting its potential utility in differential diagnosis, particularly for common subtypes such as ADD. Its simpler design may facilitate assessment in older adults, although validation in larger and more balanced cohorts is required for rarer dementias. Full article

Pareidolia is often framed as a viewer-side illusion: a tendency to perceive meaningful forms—especially faces—in ambiguous inputs. This Concept Paper argues that pareidolia can also be deliberately engineered and therefore provides a tractable entry point into the neurophysiology of visual creativity. We propose a unifying construct in which engineered pareidolia functions as externally scaffolded mental imagery: minimal visual constraints recruit internally generated templates and top-down inference while remaining anchored to sensory input. To strengthen theoretical rigor, we define necessary and sufficient features that distinguish this construct from adjacent accounts (scaffolded cognition; perceptual scaffolding; bistable perception). Using Arcimboldo’s composite portraits and Dürer’s embedded face in View of the Arco Valley, plus a canonical Renaissance example (Leonardo’s Bacchus/Saint John the Baptist), we outline distinct “design regimes” that modulate cue validity, attentional release, and interpretive switching. We then connect engineered pareidolia to creativity research by linking pareidolia design and detection to measurable constructs in divergent/creative perception, including but not limited to Torrance-style domains, and we propose feasible behavioral and neurophysiological paradigms that control for artistic skill and clinical status. Finally, we distinguish benign pareidolia from hallucination, discuss clinical resonance in dementia with Lewy bodies where pareidolia can be quantified, and outline an empirically testable research program that reframes pareidolia as a bridge between imagination, perception, and creativity. Full article