Progressive supranuclear palsy (PSP) is a tauopathic atypical parkinsonian syndrome. Recent studies suggest that inflammation may play a role in PSP pathogenesis, highlighting markers like the neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and cytokines such as IL-1β and IL-6. This study aimed to assess the relationship between peripheral inflammatory markers and psychological abnormalities in PSP-RS and PSP-P patients. The study included 24 participants: 12 with PSP-RS, 12 with PSP-P, and 12 controls. Cognitive function was assessed using the Montreal Cognitive Assessment (MoCA); however, the executive functions were evaluated using the Frontal Assessment Battery (FAB), while inflammatory markers such as IL-1β, IL6, NLR, and PLR were measured. The parameter correlation was executed using Spearman’s correlation (rs). The analysis revealed significant negative correlations between NLR and MoCA (rs = −0.48), as well as between PLR and MoCA (rs = −0.60). The negative correlation between IL-1β and MoCA was statistically significant but relatively weak. This study highlights the relevance of inflammatory markers such as NLR and PLR in reflecting cognitive decline in PSP patients, with IL-1β potentially playing a protective role in cognitive function.

Background/Objectives: Atypical parkinsonian syndromes (APSs) are a group of neurodegenerative disorders that differ from idiopathic Parkinson’s disease (IPD) in their clinical presentation, underlying pathology, and response to treatment. APSs include conditions such as multiple system atrophy (MSA), progressive supranuclear palsy (PSP), corticobasal syndrome (CBS), and dementia with Lewy bodies (DLB). These disorders are characterized by a combination of parkinsonian features and additional symptoms, such as autonomic dysfunction, supranuclear gaze palsy, and asymmetric motor symptoms. Many hypotheses attempt to explain the causes of neurodegeneration in APSs, including interactions between environmental toxins, tau or α-synuclein pathology, oxidative stress, microglial activation, and vascular factors. While extensive research has been conducted on APSs, there is a limited understanding of the symmetry in these diseases, particularly in MSA. Neuroimaging studies have revealed metabolic, structural, and functional abnormalities that contribute to the asymmetry in APSs. The asymmetry in CBS is possibly caused by a variable reduction in striatal D2 receptor binding, as demonstrated in single-photon emission computed tomography (SPECT) examinations, which may explain the disease’s asymmetric manifestation and poor response to dopaminergic therapy. In PSP, clinical dysfunction correlates with white matter tract degeneration in the superior cerebellar peduncles and corpus callosum. MSA often involves atrophy in the pons, putamen, and cerebellum, with clinical symmetry potentially depending on the symmetry of the atrophy. The aim of this review is to present the study findings on potential symmetry as a tool for determining potential neuropsychological disturbances and properly diagnosing APSs to lessen the misdiagnosis rate. Methods: A comprehensive review of the academic literature was conducted using the medical literature available in PubMed. Appropriate studies were evaluated and examined based on patient characteristics and clinical and imaging examination outcomes in the context of potential asymmetry. Results: Among over 1000 patients whose data were collected, PSP-RS was symmetrical in approximately 84% ± 3% of cases, with S-CBD showing similar results. PSP-P was symmetrical in about 53–55% of cases, while PSP-CBS was symmetrical in fewer than half of the cases. MSA-C was symmetrical in around 40% of cases. It appears that MSA-P exhibits symmetry in about 15–35% of cases. CBS, according to the criteria, is a disease with an asymmetrical clinical presentation in 90–99% of cases. Similar results were obtained via imaging methods, but transcranial sonography produced different results. Conclusions: Determining neurodegeneration symmetry may help identify functional deficits and improve diagnostic accuracy. Patients with significant asymmetry in neurodegeneration may exhibit different neuropsychological symptoms based on their individual brain lateralization, impacting their cognitive functioning and quality of life.

Introduction: Progressive supranuclear palsy (PSP) and corticobasal syndrome (CBS) are tauopathic atypical parkinsonisms. Given their overlap in terms of clinical manifestation, there is growing interest in the mechanisms leading to these entities.Materials and methods: In total, 71 patients were included in the study, 19 of whom were clinically diagnosed with CBS, 37 with PSP, and 15 with Parkinson's disease (PD). The mean ages of the participants were 72.8, 72.9, and 64.0 years, respectively, and the disease duration varied from 3 to 6 years. Each individual underwent blood collection. Morphological and biochemical evaluation of blood samples was performed to analyze the neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and neutrophil-to-high-density lipoprotein ratio (NHR). A single-photon emission computed tomography (SPECT) with technetium-99m hexamethylpropyleneamine oxime (⁹⁹Tc-HMPAO) tracer was used to assess perfusion in two regions of interest (ROI): the thalamus and insula. Using Pearson correlation to assess the linear relationship between NHR and perfusion in the insula and thalamus for CBS, PSP, and PD patients, the authors intended to verify possible correlations between NLR, PLR, and NHR and perfusion in the indicated ROIs.Results: The study revealed a negative linear correlation between NHR and perfusion of both the left (Insula L; R = −0.59) and right (Insula R; R = −0.58) insula regions. Similar to the insula, a linear correlation between NHR and activity in both the left (Thalamus L) and right (Thalamus R) thalamus regions in CBS subjects with a relatively stronger correlation in the right thalamus (R = −0.64 vs. R = −0.58) was found. These observations were not confirmed in PSP and PD patients.Conclusion: Simultaneously using non-specific parameters for peripheral inflammation (NLR, PLR, and NHR) and perfusion, SPECT may be an interesting beginning point for further analysis of inflammatory disease mechanisms. To the best of our knowledge, this is the first study to address the potential correlation between the peripheral neuroinflammatory markers NLR, PLR, and NHR and perfusion disturbances in particular ROIs.

Autoimmune cerebellar ataxia (ACA) associated with anti-Homer-3 antibodies is a rare but increasingly recognized immune-mediated neurological condition. It represents a potentially treatable cause of sporadic cerebellar syndrome and may clinically mimic primarily multiple system atrophy of the cerebellar type (MSA-C), and less frequently, other atypical parkinsonian disorders. Because of the significant clinical overlap with neurodegenerative diseases, particularly MSA-C, Homer-3–associated ACA may be underdiagnosed or misdiagnosed, delaying effective treatment. This narrative review synthesizes the currently available literature on anti-Homer-3 immunoglobulins, with a focus on their pathophysiological role, diagnostic utility, therapeutic response, and clinical differentiation from neurodegenerative conditions. Homer-3 is a postsynaptic scaffold protein expressed in Purkinje cells, where it plays a key role in calcium signaling through metabotropic glutamate receptor pathways. Antibodies against Homer-3 have been identified in patients with a wide range of neurological and neuropsychiatric symptoms, most commonly with subacute cerebellar ataxia. Neuroimaging in such cases frequently shows cerebellar atrophy or inflammation, and cerebrospinal fluid analysis often reveals inflammatory markers. The treatment with immunotherapy, particularly corticosteroids and intravenous immunoglobulins, which has showed encouraging results, however therapeutic outcomes can vary. The aim of this review is to collect and analyze all currently available data on anti-Homer-3–associated ACA, with the goal of raising clinical awareness and emphasizing the importance of early recognition and aggressive intervention.

Background: Research has associated chronic inflammation with the evolution of neurological and psychiatric disorders. Neurodegenerative diseases, including Parkinson’s Disease (PD), Alzheimer’s Disease (AD), and less common ones such as Progressive Supranuclear Palsy (PSP), are commonly linked to depression. However, the pathomechanisms and the role of neuroinflammation in these disorders remain unclear; therefore, interest is increasing in easily accessible inflammatory morphological assessments of blood samples, such as the neutrophil-to-lymphocyte ratio (NLR), the neutrophil-to-monocyte ratio (NMR), and the neutrophil-to-hemoglobin ratio (N/HGBR). Methods: The authors analyzed 15 age-matched controls and 21 patients with PSP; the PSP group was additionally divided into 11 patients without depression (PSP) and 10 with depression (Beck Depression Inventory [BDI] ≥ 14) (PSP-D). Results: In the PSP-D group, the level of N/HGBR was significantly lower than in the controls (p = 0.01), but there were no significant differences in any other neutrophil-derived parameters or comparisons of morphological blood assessment. Patients with PSP-D exhibited a marginally significant decrease in neutrophil levels compared to the controls. Conclusions: This is the first study highlighting the possible significance of peripheral inflammatory factors in patients with PSP affected by depression. It highlights possible tendencies in the area of non-specific inflammatory markers and suggests their relation to affective disorders in PSP.

Background/Objectives: Transferrin is a multi-task protein commonly known for binding iron; however, it is involved in multiple crucial processes, including antimicrobial activity, the growth of different cell types, differentiation, chemotaxis, the cell cycle, and cytoprotection. Vascular cell adhesion molecule 1 (VCAM-1) is a cell surface glycoprotein which participates in inflammation and the trans-endothelial movement of leukocytes. Neither transferrin nor VCAM-1 has been studied in the context of progressive supranuclear palsy (PSP) or corticobasal syndrome (CBS). This study aimed to evaluate the utility of transferrin and VCAM-1 assessment for the in vivo examination of tauopathic atypical Parkinsonian syndromes. Methods: This study included 10 patients with clinically probable PSP-RS, 10 with clinically probable PSP-P, and 8 with probable CBS. Patients’ blood and urine were collected and analyzed. Twenty-four serum samples (from twelve males and twelve females) were obtained from age-matched healthy volunteers. Peripheral blood inflammatory ratios, including the neutrophil-to-lymphocyte ratio, the platelet-to-lymphocyte ratio, the neutrophil-to-monocyte ratio, the neutrophil-to-high-density lipoprotein ratio, and the monocyte-to-high-density lipoprotein ratio, were calculated. VCAM-1 and transferrin concentrations were measured in the serum and urine. The urinary biomarker results are not included in the main analysis due to the absence of a control group. Results: The highest concentrations of transferrin in the serum were observed in patients with PSP-P, followed by PSP-RS and CBS. Statistically significant differences were found between PSP-P and healthy controls (p < 0.0001) and PSP-RS and healthy controls (p < 0.0001). The highest levels of serum VCAM-1 were observed in the PSP-P group. Significant differences were found between PSP-P and healthy controls (p < 0.0001), PSP-P and CBS (p < 0.001), and PSP-RS and healthy controls (p < 0.001). Serum VCAM-1 levels were negatively correlated with the NLR in CBS patients (p < 0.03; r = −0.74). Serum transferrin levels were negatively correlated with the NHR in CBS patients (p < 0.04; r = −0.64). ROC curve analyses were conducted to evaluate the diagnostic utility of serum transferrin and VCAM-1 in distinguishing tauopathic APS patients from controls. Transferrin showed excellent diagnostic performance, with an AUC of 0.975 (95% CI: 0.888–0.999; p < 0.0001), a sensitivity of 96.4%, and a specificity of 95.8% at the optimal cut-off (>503.0). VCAM-1 demonstrated good accuracy, with an AUC of 0.839 (95% CI: 0.711–0.926; p < 0.0001), a sensitivity of 75.0%, and a specificity of 91.7% at the optimal cut-off (>463.9). Conclusions: The obtained results indicate the potential role of transferrin and VCAM-1 in the pathogenesis of tauopathic APSs and highlight the need for further exploration in this field.