Search Results (159)

Background: Progressive supranuclear palsy (PSP) is a primary 4-repeat tauopathy in which neurodegeneration may be accompanied by neuroinflammatory and peripheral immune alterations. Whether peripheral inflammatory activity reflects structural degeneration within vulnerable brain networks remains unclear. Methods: This retrospective case–control study included 12 patients with PSP and 12 patients with Parkinson’s disease (PD). Automated volumetric analysis of 3-Tesla MRI was performed using volBrain 2.0. Blood-derived inflammatory indices included neutrophil-to-lymphocyte ratio (NLR), monocyte-to-lymphocyte ratio (MLR), systemic inflammation response index (SIRI), and red blood cell distribution with coefficient of variation (RDW-CV). Results: Patients with PSP showed significantly lower normalized superior frontal gyrus and pallidal volumes than patients with PD. Within the PSP group, higher values of selected blood-derived inflammatory indices were associated with lower frontal network volumes. After adjustment for age, MLR was inversely associated with the composite Frontal Network Score (partial r = −0.7333, p = 0.0067, FDR q = 0.020). The strongest regional association was observed between SIRI and medial frontal cortex volume (rho = −0.748, p = 0.0051); however, regional associations did not remain significant after FDR correction. Conclusions: Peripheral inflammatory markers were associated with MRI-derived measures of frontal network degeneration in PSP. The association between MLR and the composite Frontal Network Score supports a link between systemic immune alterations and network-level neurodegeneration in PSP. Full article

Wearable inertial measurement units (IMUs) offer an accessible alternative to optical motion capture (MoCap) gait analysis, but their performance in Progressive Supranuclear Palsy (PSP) requires validation. We assessed the concurrent validity of IMU-derived versus MoCap-derived gait metrics and static postural sway in 30 patients with PSP using Bland–Altman analysis, Intraclass Correlation Coefficients (ICC), and Spearman rank correlations. Finally, we assessed equivalence using the Two one-sided tests (TOST) procedure. Multivariable linear regression was used to determine whether clinical severity, as measured by the PSP Rating Scale (PSPRS), independently predicted absolute IMU measurement error while controlling for patient age and gait velocity. IMUs demonstrated excellent between-system agreement for parameters such as cadence (100.76 ± 11.42 vs. 100.52 ± 11.59) and cycle time (1.21 ± 0.15 vs. 1.22 ± 0.15; ICC > 0.98), despite a systematic underestimation of gait velocity (p < 0.05). Agreement significantly diminished for micro-phases (e.g., single/double support times) and spatial asymmetry. Interestingly, the TOST procedure revealed that only sagittal and transverse trunk kinematics were equivalent between systems, with all other measures failing to find equivalency. For static sway, the IMU demonstrated strong rank-order correspondence for tracking relative postural instability (ρ = 0.82, p < 0.05). Multivariable analysis revealed that higher PSPRS scores are independently associated with greater between-system discrepancies in support phases and pelvic and trunk kinematics (p < 0.05), irrespective of reduced gait speed. These findings highlight the need to develop disease-specific algorithms, rather than relying on normative commercial models, to establish reliable digital biomarkers for monitoring progressive motor decline. Full article

Background/Objectives: Evidence suggests that inflammation contributes to the pathogenesis of neurodegenerative disorders. The utility of blood-derived inflammatory biomarkers in differentiating neurodegenerative disorders remains incompletely understood. The aim of this study was to compare peripheral inflammatory markers in patients with essential tremor (ET), Parkinson’s disease (PD), progressive supranuclear palsy (PSP), and control participants. Methods: This retrospective study included 44 patients with ET, 47 with PD, 44 with PSP, and 45 control participants. The neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), monocyte-to-lymphocyte ratio (MLR), systemic immune-inflammation index (SII), systemic inflammation response index (SIRI), and aggregate index of systemic inflammation (AISI) were calculated from routine complete blood counts. Between-group comparisons were performed using the Kruskal–Wallis test, with a Holm correction across the six indices. The effect sizes were also estimated. Results: The PLR was the only inflammatory marker that significantly differentiated the analyzed groups (p = 0.045), with the highest value observed in PSP patients and the lowest in ET patients. A post hoc analysis indicated different PLR values in PSP than in ET patients (Cliff’s delta = 0.336, small-to-moderate effect). However, the overall association did not remain statistically significant after Holm correction across the six indices (adjusted p = 0.268), and the diagnostic group was not independently associated with PLR after adjustment for age and sex. No statistically significant differences were observed for the NLR, MLR, SII, SIRI, or AISI. Nevertheless, PSP patients consistently exhibited the highest median values of the NLR, SII, and AISI, whereas ET patients generally showed lower inflammatory marker levels. Conclusions: PLR was the only inflammatory marker that significantly differentiated the analyzed groups and was the highest among patients with PSP. The observed trends suggest a tendency toward greater peripheral immune activation in PSP compared with PD and ET. Larger prospective studies incorporating both inflammatory and neurodegenerative biomarkers are warranted to validate these findings. Full article

Background/Objectives: Progressive supranuclear palsy (PSP) and Parkinson’s disease (PD) share several clinical manifestations, which may complicate differential diagnosis. The aim of this study was to evaluate whether automated volumetric measurements of the pallidum and ventral diencephalon can differentiate PSP from PD. Methods: Thirty-two patients were included, comprising 20 patients with PD and 12 patients with PSP. All participants underwent 3-T brain magnetic resonance imaging. Automated segmentation and volumetric analysis were performed using the vol2Brain pipeline. Absolute and normalized volumes of the pallidum and ventral diencephalon were compared between groups. Receiver operating characteristic (ROC) analysis was used to assess diagnostic performance. Results: Patients with PSP demonstrated lower pallidal and ventral diencephalic volumes than patients with PD. Differences were observed for both absolute and normalized volumetric measurements (all p ≤ 0.002). Total pallidal volume showed the highest diagnostic performance, with an area under the ROC curve (AUC) of 0.958, sensitivity of 85%, and specificity of 100%. Total ventral diencephalon volume also differentiated PSP from PD, yielding an AUC of 0.829, seNsitivity of 70%, and specificity of 92%. Conclusions: Pallidal and ventral diencephalic volumes differed between patients with PSP and PD. Automated measurements of pallidal and ventral diencephalic volumes may complement conventional MRI findings in patients with parkinsonian syndromes. Further studies are needed to validate these findings in larger cohorts. Full article

Introduction: Progressive supranuclear palsy (PSP) is an atypical Parkinsonian disorder characterized by a range of clinical phenotypes, reflecting its multiple subtypes. As a result, accurate diagnosis during life remains challenging, underscoring the need for reliable biomarkers. The present narrative review aims to evaluate whether dopamine transporter single-photon emission computed tomography (DaT-SPECT) can serve as a biomarker in the assessment of PSP. Methods: The database search identified 31 original research articles relevant to our study objective. Of these, 17 studies included PSP patients and utilized DaT-SPECT as the sole molecular imaging modality; 9 studies combined DaT-SPECT with at least one additional molecular imaging technique; and 5 studies integrated DaT-SPECT with a laboratory-based biomarker of neurodegenerative disease. Results: DaT-SPECT appears to demonstrate low specificity and variable sensitivity for PSP across studies. Discussion: Combining DaT-SPECT with other diagnostic biomarkers, especially brain magnetic resonance imaging and other nuclear imaging modalities, may improve diagnostic accuracy, especially given its relatively low specificity for PSP. Nevertheless, these initially promising findings need to be validated in large, multicenter studies that include and clearly define multiple, autopsy-confirmed PSP subtypes. Full article

Tauopathies, including Alzheimer’s disease (AD), progressive supranuclear palsy (PSP), corticobasal degeneration (CBD), and frontotemporal lobar degeneration with tau pathology, are unified by pathogenic tau misfolding, post-translational modification, aggregation, and network-level spread. Yet decades of drug development that predominantly pursued single nodes (e.g., one kinase, one aggregation inhibitor, one monoclonal antibody epitope) have repeatedly delivered late-stage disappointments, underscoring a central lesson: tauopathy behaves less like a linear pathway and more like a coupled system of proteostasis failure, neuroinflammation, synaptic-mitochondrial stress, and metabolic dysregulation. This review examines rhizomes (notably Zingiberaceae genera such as Curcuma, Zingiber, Alpinia, Kaempferia, and Boesenbergia) as chemically diverse “multi-target platforms” whose bioactives can engage several tau-relevant nodes simultaneously. We synthesise evidence across tau phosphorylation (GSK-3β/CDK5 and upstream stress signalling), tau aggregation and seeding, autophagy-lysosome and proteasome pathways, redox-mitochondrial resilience, neuroinflammatory circuits (NF-κB/NLRP3), and neuro-metabolic signalling (insulin-PI3K-AKT, AMPK-mTOR). A translational lens is applied throughout, focusing on drug-likeness and CNS multiparameter optimisation; BBB permeability and efflux; metabolism and bioavailability constraints; and formulation strategies (nanoparticles, phytosomes, engineered exosomes) that may render rhizome-derived scaffolds more clinically plausible. We conclude that rhizomes offer credible mechanistic hypotheses for tau modulation, but progress depends on rigorous standardisation, realistic exposure matching, biomarker-driven study design, and a shift from “single-compound optimism” to network pharmacology with translational discipline. 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

Progressive supranuclear palsy-Richardson’s syndrome (PSP-RS) is a primary 4R tauopathy in which early axonal dysfunction may precede overt neurodegeneration; however, the mechanisms linking Tau dysregulation to cytoskeletal vulnerability remain poorly defined. Here, we generated induced pluripotent stem cell (iPSC)-derived midbrain dopaminergic neurons from individuals with sporadic PSP-RS and matched healthy controls and performed integrated transcriptomic and proteomic analyses. PSP-RS neurons exhibited coordinated suppression of dopaminergic and synaptic programs alongside activation of cytoskeletal remodeling and stress-related pathways. These changes were accompanied by increased Tau phosphorylation, neurofilament accumulation, and structural alterations of the axonal compartment, consistent with an early axonopathic phenotype. Notably, mechanistic target of rapamycin (mTOR) signaling significantly increased. Pharmacological inhibition of mTOR reduced Tau phosphorylation and neurofilament levels, indicating that mTOR activity contributes to the maintenance of cytoskeletal imbalance. In conclusion, our findings support a model in which early cytoskeletal dysfunction in PSP-RS arises from the convergence of Tau dysregulation, impaired structural homeostasis, and altered signaling pathways. Rather than acting as a primary driver, mTOR appears to function as a pathogenic amplifier that sustains axonal stress. This study provides a human cellular framework to investigate early axonopathic mechanisms in sporadic PSP-RS. Full article

Cerebrospinal fluid (CSF) biomarkers for neurodegenerative diseases have been extensively studied over the years. However, CSF samples are routinely centrifuged, and the resulting sediment or pellet is typically discarded to remove cellular debris and high-density particles. This standard practice raises a critical question: Could these discarded sediments harbour potential biomarkers? The aim of the present study is to demonstrate that CSF sediments contain specific brain-derived components and thus to substantiate the possible presence of biomarkers within these sediments. To this end, we analysed post-mortem CSF samples of one patient with neuropathologically confirmed Alzheimer’s disease (AD) and one patient with confirmed progressive supranuclear palsy (PSP). CSF pellets were studied using transmission and scanning electron microscopy techniques (TEM and SEM, respectively), along with compositional analysis through SEM combined with energy-dispersive X-ray spectroscopy (SEM-EDX), as well as immunofluorescence and histochemical analyses on semithin pellet sections. We observed that, among others, CSF pellets contain brain-derived structures such as wasteosomes and psammoma bodies. Furthermore, we also found disease-relevant proteins, including tau and Aβ42 in the AD sediment and tau in the PSP sediment. Although further studies are required, the study of CSF pellets could open new avenues for biomarker discovery in neurodegenerative diseases. Full article

Mild behavioral impairment (MBI) is a clinical syndrome characterized by the late-life onset and persistence of neuropsychiatric symptoms (NPSs), representing a change from longstanding behavior or personality and considered a potential prodrome of neurodegenerative disease. MBI is classified into five domains: decreased motivation, affective dysregulation, impulse dyscontrol, social inappropriateness, and psychotic symptoms. In this narrative review, we synthesize clinical, neuroanatomical, and molecular evidence linking MBI to the spectrum of tauopathies, including Alzheimer’s disease (AD), frontotemporal spectrum disorders (FTSDs), and primary four-repeat tauopathies such as progressive supranuclear palsy (PSP) and corticobasal degeneration (CBD). Emerging evidence suggests that early behavioral symptoms associated with MBI may reflect the selective vulnerability of frontolimbic, salience, default mode, and frontostriatal networks to tau-mediated neurodegeneration. Mechanistically, converging findings support roles for tau-related synaptic dysfunction, including synaptotoxic soluble tau species, cytoskeletal and axonal transport disruption, monoaminergic neurotransmitter imbalance in brainstem systems, and neuroinflammatory and glial pathways. We also highlight genotype-related behavioral profiles in genetic frontotemporal lobar degeneration and discuss how scalable blood-based biomarkers, including neurofilament light chain, glial fibrillary acidic protein, and plasma phospho-tau species, may complement MBI-based phenotyping for differential diagnosis and prognostic stratification in clinical research. Full article

Diagnosis of atypical parkinsonian syndromes (APS), including progressive supranuclear palsy (PSP) and multiple system atrophy (MSA), rely on clinical criteria that often result in misclassification or delayed confirmation. Cerebrospinal fluid (CSF) metabolomics offers the potential to identify disease-specific biochemical “fingerprints”. The aim of the study is to identify CSF metabolomic biomarkers that distinguish PSP and MSA from each other and from non-neurodegenerative controls. Targeted mass spectrometry-based metabolomics was performed on CSF samples from 30 patients with MSA, 41 with PSP, and 30 age- and sex-matched non-neurodegenerative controls. Global metabolomic profiles showed no clear group separation. Both PSP and MSA showed elevated gut-derived metabolites p-cresyl sulfate and deoxycholic acid versus controls. In PSP, decreased cortisone and increased hexosylceramide d18:1/24:1 were observed, whereas in MSA, dihydroxyphenylalanine was elevated alongside homoarginine and creatinine. In the direct comparison of APS, levels of α-aminoadipic acid were increased in PSP compared to MSA. Pathway analysis highlighted disrupted glycerophospholipid metabolism in both APS disorders. Distinct metabolite panels mainly combining membrane-associated lipids, gut-derived and neurotransmitter-related metabolites demonstrated high diagnostic accuracy for distinguishing PSP and MSA from control groups (AUC = 0.95 for PSP and AUC = 0.98 for MSA), while a separate panel showed moderate performance in differentiating PSP from MSA (AUC = 0.85). Distinct but partially overlapping CSF metabolomic profiles characterize PSP and MSA. These metabolomic fingerprints highlight gut–brain axis involvement, alterations in cell membrane-related lipid metabolism, and disease-specific changes in neurotransmitter-related metabolites. Further, a panel of these metabolites showed strong potential as diagnostic biomarkers. Full article

Transcranial sonography is one of the methods of examination used in atypical parkinsonian syndromes. The assessment is not indicated in the diagnostic criteria of entities in this group e.g., Progressive Supranuclear Palsy, Corticobasal Degeneration, Multiple System Atrophy and Dementia with Lewy Bodies. Atypical parkinsonisms are a group of diseases affected by diverse pathologies including alpha-synuclein or tau among others. Recently broader attention was brought to less common atypical parkinsonisms as Perry syndrome. Atypical parkinsonisms are related to poor response to levodopa treatment, rapid deterioration and unfavorable prognosis. Additionally, the entities often overlap in terms of clinical manifestation, especially in the early stages. Though atypical parkinsonisms are affected by the lack of possibility of obtaining definite in vivo diagnosis, growing interest is associated to supplementary evaluations including neuroimaging. Among these methods could be mentioned magnetic resonance imaging, positron emission tomography, single photon emission computed tomography and transcranial sonography. Transcranial sonography is associated with high accessibility and low cost. The goal of this paper is to highlight the strengths and weaknesses of transcranial sonography in the examination of atypical parkinsonisms. Full article

Parkinson’s disease (PD) is a heterogeneous clinical syndrome representing the final stage of a complex and long-lasting neurodegenerative process that involves not only dysfunction of the dopaminergic system but also impairments in other neurotransmitter systems. The diversity of the clinical presentation of PD, together with the existence of Parkinsonian syndromes and atypical Parkinsonism—such as multiple system atrophy (MSA), progressive supranuclear palsy (PSP), and dementia with Lewy bodies (DLB)—has important implications for rehabilitation outcomes and underscores the need for individualized, stage-dependent therapeutic approaches. Juggling is a complex motor activity that integrates cognitive, visuomotor, and balance processes, requiring a high level of concentration, precision, and motor adaptation. In recent years, there has been growing interest in this form of activity as a potential tool for supporting neuroplasticity, cognitive functions, and neurological rehabilitation. The aim of this review was to summarize current scientific evidence on the effects of juggling training on cognitive functions, visuomotor coordination, and balance, as well as to discuss the potential benefits of combining it with controlled hypoxia in patients with Parkinson’s disease (PD). This narrative review additionally considers how disease heterogeneity and stage of progression may influence the effectiveness of such multimodal interventions. This paper reviews the literature concerning the neurophysiological basis of learning to juggle and the mechanisms of brain plasticity, including increases in gray matter volume, improvements in white matter integrity, and reorganization of neuronal networks in motor and associative regions. Attention is drawn to the synergistic potential of combining juggling training with exposure to moderate, controlled hypoxia, which may induce an adaptive response involving the transcription factor HIF-1α, enhance the expression of brain-derived neurotrophic factor (BDNF), and promote angiogenesis and mitochondrial biogenesis. Although juggling and hypoxia are not directly related to training stimuli, both interventions activate overlapping and complementary neuroplastic pathways, providing a conceptual rationale for their parallel consideration and potential integration within future rehabilitation protocols. Juggling delivers task-specific motor–cognitive learning, whereas hypoxia may amplify molecular plasticity signaling, potentially enhancing responsiveness to motor interventions, particularly in patients at early stages of PD when compensatory mechanisms and neuroplastic capacity are relatively preserved. Findings from existing studies suggest that juggling under controlled hypoxic conditions may represent an innovative, safe, and multimodal form of training that supports both cognitive and motor components. Such effects may be particularly relevant in patients at early stages of PD, when compensatory mechanisms and neuroplastic potential are relatively preserved. Such an intervention may contribute to improvements in balance, attention, executive functions, and cognitive flexibility, which is particularly relevant in the context of rehabilitation for patients with neurodegenerative diseases. Importantly, to date, no randomized clinical trials have directly examined juggling performed under controlled hypoxic conditions in PD. Therefore, the present concept should be regarded as translational and exploratory, integrating evidence from juggling-induced neuroplasticity and hypoxia-related physiological adaptations. In this context, the proposed approach represents a proof-of-concept framework for future multimodal interventions rather than an established therapeutic strategy. Available evidence suggests that combining complex sensorimotor skill training with physiological modulation of the internal environment may constitute a novel direction in PD rehabilitation, extending beyond conventional exercise-based models. Despite promising reports, further well-designed clinical studies are needed to determine the optimal training parameters (frequency, intensity, duration, and degree of hypoxia), to evaluate the long-term sustainability of therapeutic effects, and to account for the heterogeneity of PD and related Parkinsonian disorders. Full article

Background: In Parkinson’s disease (PD), a higher prevalence of polyneuropathy (PNP) is increasingly recognized, although the causal association is still under debate. In contrast, PNP in atypical parkinsonian syndromes (APS) has been insufficiently addressed, despite preliminary evidence suggesting elevated prevalence. Methods: Nerve conduction studies were performed on 13 patients with multiple system atrophy (MSA) and 9 patients with progressive supranuclear palsy (PSP) at baseline. PNP was diagnosed according to standard electrophysiological criteria after exclusion of common secondary causes. Comprehensive clinical evaluation included motor and non-motor assessments over two years of follow-up. Results: At baseline, PNP was present in 53.8% of MSA patients and 66.7% of PSP patients. MSA patients with PNP showed greater motor symptom severity (UPDRS III score; p = 0.046) and worse cognitive performance (MoCA; p = 0.044) compared to those without PNP. Over two years, a significant reduction in the tibial nerve amplitude was observed exclusively in MSA patients (p = 0.039), paralleling disease progression. Conclusions: This study provides the first longitudinal evaluation of clinical and electrophysiological PNP progression in MSA and PSP. A high comorbidity of PNP in patients with APS could contribute to motor and sensory impairments in these patients. Our findings indicate that PNP progression may reflect disease progression in MSA. Given the limited sample size, larger-scale longitudinal studies are needed to further investigate biomarker potential of PNP in APS and to clarify differences in peripheral nerve involvement between synucleinopathies and tauopathies. Full article

Background/Objectives: Clinical differentiation between Parkinson’s disease (PD) and atypical parkinsonism (AP) remains complex. Current diagnostic procedures helpful in their distinction lack specificity, making non-invasive tools like optical coherence tomography (OCT) crucial in evaluating possible retinal changes as potential biomarkers. Our study examined the thickness of the ganglion cell inner plexiform layer complex (GCIPL), peripapillary retinal nerve fiber layer (RNFL) and macular segments in individuals with PD, multiple system atrophy (MSA), progressive supranuclear palsy (PSP), and healthy controls (HC). The objective of our study was to determine if OCT analyses can effectively discriminate PD patients from HC and whether retinal thickness can distinguish typical PD patients from those with AP. Methods: Research was an observational, cross-sectional study. Multiple retinal layers measured with OCT of PD and AP patients were compared with age- and sex-matched HC. An intergroup assessment was conducted. Results: Patients with PD and PSP exhibit a thinner GCIPL compared to HC, with no difference observed in the MSA group. GCIPL thickness between investigational groups does not differentiate between PD and AP. The RNFL and central macula thickness were statistically significantly reduced in all patient groups compared to HC. The RNFL was thinner in PSP compared to PD. Nearly all inner and outer macular segments were thinner in the investigational groups compared to HC. The preservation of outer nasal segments distinguished HC from both typical and AP. Patients with PSP and PD differed in the thickness of all macular segments, being thinner in PSP patients. Conclusions: Thickness of multiple retinal layers and macular regions might serve as a distinguishing feature between PD, AP and HC. Full article