Nervous System Pathology Research Articles

Case report: Polymorphous low-grade neuroepithelial tumor of the young and supratentorial ependymoma diagnosed in an adult male

Polymorphous low-grade neuroepithelial tumor of the young (PLNTY) is a rare central nervous system (CNS) pathology predominantly observed in the pediatric population. Ependymomas also exhibit a peak incidence in early childhood, with rare presentations after early adulthood. In this report, we describe a rare case of a 41-year-old man diagnosed sequentially with a polymorphous low-grade neuroepithelial tumor of the young, followed by a supratentorial ependymoma within a year. He underwent tumor resection for both tumors, as well as adjuvant radiation therapy for the ependymoma. Despite these interventions, he ultimately succumbed to tumor progression and postoperative complications. Currently, no genetic syndromes are known to link these two primary CNS tumors. Two commonalities at the chromosomal and cellular level include histone gene H3F3A mutations and positive glial fibrillary acidic protein staining on immunohistochemistry. To the best of our knowledge, this unique dual pathology has not been previously described in the literature, making this case an avenue for further investigation and research into connections between these two distinct CNS pathologies.

Recent advances in neuro-ophthalmology.

This review article represents a collaborative effort across continents, bringing together the latest developments in neuro-ophthalmology with a focus on innovative diagnostic and therapeutic modalities that are shaping the future of the field. Among the most significant advancements is the rise of optical coherence tomography (OCT), now recognized as an indispensable tool in neuro-ophthalmological research, providing unparalleled insights into optic nerve and central nervous system pathologies. Gene therapy, particularly for conditions such as Leber's hereditary optic neuropathy, marks a new frontier in personalized medicine, offering hope for previously untreatable conditions. The article also examines the transformative role of telemedicine and artificial intelligence (AI) in clinical practice, which are revolutionizing patient care and enhancing diagnostic precision. Furthermore, it highlights the impact of novel serological biomarkers on the understanding and management of immune-mediated optic neuritis, and discusses the introduction of new therapeutic agents like Tocilizumab and Teprotumumab, which are redefining treatment paradigms. Collectively, these advancements reflect the profound influence of modern medicine on neuro-ophthalmology, paving the way for improved patient outcomes and fostering new avenues for research and clinical practice.

Diaphragmatic Paralysis Following Chest Tube Insertion in an Infant

Diaphragmatic paralysis (DP) can occur due to central nervous system pathology or peripheral nerve injury. Direct injury to the phrenic nerve after intercostal chest drain (ICD) insertion for treatment of pneumothorax is an infrequent complication. We present a 4-month-old baby, ex-preterm 27 weeks, who was admitted to a tertiary care hospital pediatric intensive care unit in Muscat, Oman, in 2023 with severe respiratory syncytial virus bronchiolitis and required intubation and mechanical ventilation (MV). His illness was complicated by right-side pneumothorax that required ICD insertion. Post-extubation, he had persistent tachypnea with the inability to be weaned from noninvasive ventilation (NIV). Chest x-ray (CXR) and fluoroscopy showed a high right diaphragm dome with paradoxical movements. He improved dramatically after the plication of the right diaphragm and was discharged home on the 9th day after the plication.

Zinc signaling controls astrocyte-dependent synapse modulation via the PAF receptor pathway.

Astrocytes are important regulators of neuronal development and activity. Their activation plays a key role in the response to many central nervous system (CNS) pathologies. However, reactive astrocytes are a double-edged sword as their chronic or excessive activation may negatively impact CNS physiology, for example, via abnormal modulation of synaptogenesis and synapse function. Accordingly, astrocyte activation has been linked to neurodegenerative and neurodevelopmental disorders. Therefore, the attenuation of astrocyte activation may be an important approach for preventing and treating these disorders. Since zinc deficiency has been consistently linked to increased pro-inflammatory signaling, we aimed to identify cellular zinc-dependent signaling pathways that may lead to astrocyte activation using techniques such as immunocytochemistry and protein biochemistry to detect astrocyte GFAP expression, fluorescent imaging to detect oxidative stress levels in activated astrocytes, cytokine profiling, and analysis of primary neurons subjected to astrocyte secretomes. Our results reveal a so far not well-described pathway in astrocytes, the platelet activation factor receptor (PAFR) pathway, as a critical zinc-dependent signaling pathway that is sufficient to control astrocyte reactivity. Low zinc levels activate PAFR signaling-driven crosstalk between astrocytes and neurons, which alters excitatory synapse formation during development in a PAFR-dependent manner. We conclude that zinc is a crucial signaling ion involved in astrocyte activation and an important dietary factor that controls astrocytic pro-inflammatory processes. Thus, targeting zinc homeostasis may be an important approach in several neuroinflammatory conditions.

Neuroimmunology frontiers: Unveiling immune mechanisms in central nervous system repair and pathology

Neuroimmunology frontiers: Unveiling immune mechanisms in central nervous system repair and pathology

Dark Microglia Are Abundant in Normal Postnatal Development, where they Remodel Synapses via Phagocytosis and Trogocytosis, and Are Dependent on TREM2.

This study examined dark microglia-a state linked to central nervous system pathology and neurodegeneration-during postnatal development in the mouse ventral hippocampus, finding that dark microglia interact with blood vessels and synapses and perform trogocytosis of pre-synaptic axon terminals. Furthermore, we found that dark microglia in development notably expressed C-type lectin domain family 7 member A (CLEC7a), lipoprotein lipase (LPL) and triggering receptor expressed on myeloid cells 2 (TREM2) and required TREM2, differently from other microglia, suggesting a link between their role in remodeling during development and central nervous system pathology. Together, these results point towards a previously under-appreciated role for dark microglia in synaptic pruning and plasticity during normal postnatal development.

Torque teno virus (TTV) Infection in Patients with Encephalitis

Torque teno virus (TTV) is a ssDNA orphan virus belonging to the Anelloviridae family, but some recent studies suggested its possible involvement in central nervous system (CNS) pathology. We analyzed serum and cerebrospinal fluid samples (CSF) from 109 patients with encephalitis for TTV infection using serological and molecular testing, virus quantitative measurement, and next-generation sequencing-based (NGS) phylogenetic analysis. TTV noncoding region (UTR) and/or open reading frame 1 (ORF-1) sequences were detected in serum of 86 (79%) patients and in nine (8%) patients in CSF. Five of the latter patients were coinfected with various entero- and herpesviruses. Anti-TTV-IgG were detected in 80 (73.4%) sera and in two (1.8%) CSF samples, while anti-TTV-IgM were present in three (2.8%) sera and in none of the CSFs. Phylogenic analysis of CSF-derived TTV ORF-1 sequences revealed the presence of three unique variants in one patient. TTV was quantified in five CSF-serum pairs: in two patients viral loads were similar, and in three serum TTV loads were approximately one log higher. Our results suggest at least an occasional replication of TTV in CNS. However, whether TTV could be the cause of encephalitis requires further studies.

Choroid Plexus Pathophysiology.

This review examines the crucial roles of the choroid plexus (ChP) in central nervous system (CNS) pathology, emphasizing its involvement in disease mechanisms and therapeutic potential. Structural changes in the human ChP have been reported across various diseases in case reports and descriptive work, but studies have yet to pin down the physiological relevance of these changes. We highlight primary pathologies of the ChP, as well as their significance in neurologic disorders, including stroke, hydrocephalus, infectious diseases, and neurodegeneration. Synthesizing recent research, this review positions the ChP as a critical player in CNS homeostasis and pathology, advocating for enhanced focus on its mechanisms to unlock new diagnostic and treatment strategies and ultimately improve patient outcomes in CNS diseases. Whether acting as a principal driver of disease, a gateway for pathogens into the CNS, or an orchestrator of neuroimmune processes, the ChP holds tremendous promise as a therapeutic target to attenuate a multitude of CNS conditions.

Biomarker Profiles in Serum and CSF for Early Diagnosis of Selected Neurodegenerative Diseases

Biomarker research and justification for neurodegenerative illnesses have seen enormous efforts over the last ten years. Bio-fluid-based biomarkers have been believed to provide a better and easier approach to detecting biomarkers for diagnosing nervous system pathologies. Objectives: To evaluate the diagnostic potential of certain biomarkers in serum and cerebrospinal fluid to diagnose Alzheimer’s disease, Parkinson’s disease, and Huntington’s disease at an initial stage. Methods: 280 participants were taken and distributed into four groups, comprising, 70 patients with early-stage Alzheimer’s disease, 70 with early-stage Parkinson’s disease, 70 with early-stage Huntington’s disease, and 70 age-matched healthy controls. Blood and cerebrospinal fluid samples were drawn and medical history was taken from the patients. Serum and cerebrospinal fluid levels of amyloid-beta (Aβ42), total tau (t-tau), phosphorylated tau (p-tau), alpha-synuclein, huntingtin protein, and neuro-filament light chain were evaluated using enzyme-linked immunosorbent assays. Results: Alzheimer’s disease patients showed reduced serum Aβ42 (80.4 ± 15.6 pg/mL) and elevated t-tau (140.5 ± 18.2 pg/mL). Parkinson’s disease patients had raised serum alpha-synuclein (12.5 ± 2.3 ng/mL) and neuro-filament light chain. Huntington’s disease patients showed significant increases in serum huntingtin protein (8.2 ± 2.0 ng/mL). These profiles indicate efficacy in early diagnosis. Conclusions: It was concluded that Aβ42 and tau effectively detect Alzheimer’s disease, while Parkinson’s disease patients can be effectively diagnosed with Serum and cerebrospinal fluid levels of the neuro-filament light chain. Similarly, huntingtin protein and neuro-filament light chain are sensitive enough to detect Huntington’s disease at its early stages.

Scrambler therapy for treatment of poststroke pain

AbstractObjectiveStrokes involving sensory pathways can result in contralesional pain syndromes often refractory to pharmacologic interventions. Scrambler therapy (ST) is a noninvasive electroanalgesia device used to treat pain caused by peripheral neuropathy; however, data are scarce regarding its use in conditions secondary to central nervous system pathology. We evaluate the efficacy of ST to treat poststroke pain.MethodsTwenty patients with a history of prior stroke resulting in contralesional pain were randomized to receive ST or Sham as an adjunct to their stable medication regimen. Participants underwent 5 consecutive daily 40‐min sessions. The study was blinded to patient and assessor. Pain scores (0–10) were recorded at baseline, pre‐ and postsession, and 4 weeks after final treatment. Student's t‐tests compared differences in the mean change in pain score between groups immediately post‐treatment #5, and at 4‐weeks. The chi‐squared analysis compared the proportion of patients in each group with >50% pain reduction.ResultsParticipants randomized to ST had a mean change in pain score of −3.73 (SD 2.85) postintervention and −2.57 (SD 2.07) at 4 weeks, while the Sham group had a mean change in score of −0.94 (SD 1.36) and −0.25 (SD 0.84) (p between groups = 0.012, 0.004, respectively). Significantly more participants treated with ST reported a >50% reduction in pain immediately postintervention compared to Sham (70% vs. 10%, p = 0.006), but not at follow‐up (30% vs. 10%, p = ns).InterpretationST may effectively decrease poststroke pain compared to Sham. Larger studies are needed to evaluate confounders such as stroke location, time from stroke, and concomitant treatment with medications.

Lactylation: A Novel Post-Translational Modification with Clinical Implications in CNS Diseases.

Lactate, an important metabolic product, provides energy to neural cells during energy depletion or high demand and acts as a signaling molecule in the central nervous system. Recent studies revealed that lactate-mediated protein lactylation regulates gene transcription and influences cell fate, metabolic processes, inflammation, and immune responses. This review comprehensively examines the regulatory roles and mechanisms of lactylation in neurodevelopment, neuropsychiatric disorders, brain tumors, and cerebrovascular diseases. This analysis indicates that lactylation has multifaceted effects on central nervous system function and pathology, particularly in hypoxia-induced brain damage. Highlighting its potential as a novel therapeutic target, lactylation may play a significant role in treating neurological diseases. By summarizing current findings, this review aims to provide insights and guide future research and clinical strategies for central nervous system disorders.

Emerging Role of Extracellular Vesicles as Biomarkers in Neurodegenerative Diseases and Their Clinical and Therapeutic Potential in Central Nervous System Pathologies.

The emerging role of extracellular vesicles (EVs) in central nervous system (CNS) diseases is gaining significant interest, particularly their applications as diagnostic biomarkers and therapeutic agents. EVs are involved in intercellular communication and are secreted by all cell types. They contain specific markers and a diverse cargo such as proteins, lipids, and nucleic acids, reflecting the physiological and pathological state of their originating cells. Their reduced immunogenicity and ability to cross the blood-brain barrier make them promising candidates for both biomarkers and therapeutic agents. In the context of CNS diseases, EVs have shown promise as biomarkers isolable from different body fluids, providing a non-invasive method for diagnosing CNS diseases and monitoring disease progression. This makes them useful for the early detection and monitoring of diseases such as Alzheimer's, Parkinson's, and amyotrophic lateral sclerosis, where specific alterations in EVs content can be detected. Additionally, EVs derived from stem cells show potential in promoting tissue regeneration and repairing damaged tissues. An evaluation has been conducted on the current clinical trials studying EVs for CNS diseases, focusing on their application, treatment protocols, and obtained results. This review aims to explore the potential of EVs as diagnostic markers and therapeutic carriers for CNS diseases, highlighting their significant advantages and ongoing clinical trials evaluating their efficacy.

Physcion Mitigates LPS-Induced Neuroinflammation, Oxidative Stress, and Memory Impairments via TLR-4/NF-кB Signaling in Adult Mice.

Alzheimer's disease (AD) is the most predominant cause of dementia, considered a progressive decline in cognitive function that ultimately leads to death. AD has posed a substantial challenge in the records of medical science over the past century, representing a predominant etiology of dementia with a high prevalence rate. Neuroinflammation is a common characteristic of various central nervous system (CNS) pathologies like AD, primarily mediated by specialized brain immune and inflammatory cells, such as astrocytes and microglia. The present study aims to elucidate the potential mechanism of physcion that mitigates LPS-induced gliosis and assesses oxidative stress in mice. Physcion reduced the reactivity of Iba-1- and GFAP-positive cells and decreased the level of inflammatory cytokines like TNF-α and IL-1β. Physcion also reversed the effect of LPS-induced oxidative stress by upregulating the expression of Nrf2 and HO-1. Moreover, physcion treatment reversed LPS-induced synaptic disorder by increasing the level of presynaptic protein SNAP-23 and postsynaptic protein PSD-95. Our findings may provide a contemporary theoretical framework for clinical investigations aimed at examining the pathogenic mechanisms and therapeutic approaches for neuroinflammation and AD.

Prospects for the Use of Thymoquinone (a Component of Nigella sativa) in the Prevention and Therapy of Neuropathologies

Black cumin and its component thymoquinone (TQ) are known as drugs with a wide range of pharmacological activities: immunomodulating, anti-inflammatory, antimicrobial, antiviral, antineoplastic properties. These drugs also have neuroprotective properties in neurodegenerative diseases (Alzheimer's, Parkinson's), ischaemia, epilepsy, encephalomyelitis, traumatic brain injury. The main mechanisms of action are antioxidant activity increased expression of neuroprotective genes and proteins with decreased activity of pro-inflammatory cytokines and the NF-кB pathway, which plays a key role in neuroinflammation. A separate section is devoted to the effects of black cumin and TQ on the course of depression, a common and socially significant illness. Reduced signs of depression and increased levels of a neuroprotective factor belonging to the neutrophin family (BDNF), a characteristic marker of depression, were described in 54 depressed patients. The review discusses the prospects for prevention and therapy with these drugs in central nervous system pathology.

Gender-specific microbial signatures in saliva: Unveiling the association between the oral microbiome and the pathogenesis of glioma

The intricate interplay between the human oral microbiome and systemic health is increasingly being recognized, particularly in the context of central nervous system pathologies such as glioblastoma. In this study, we aimed to elucidate gender-specific differences in the salivary microbiome of glioma patients by utilizing 16S rRNA sequencing data from publicly available salivary microbiome datasets. We conducted comprehensive bioinformatics analysis, encompassing quality control, noise reduction, species classification, and microbial community composition analysis at various taxonomic levels. Machine learning algorithms were employed to identify microbial signatures associated with glioma. When compared to healthy controls, our analysis revealed distinct differences in the salivary microbiota of glioma patients. Notably, the genera Leptotrichia and Atopobium exhibited significant variations in abundance between genders. Leptotrichia was prevalent in healthy females but exhibited a reduced abundance in female glioma patients. In contrast, Atopobium was more abundant in male glioma patients. These findings suggest that hormonal influences might play a role in shaping the salivary microbiome and its association with glioma. We utilized a combination of LASSO-logistic regression and random forest models for feature selection, and identified key microbial features that differentiated glioma patients from healthy controls. We developed a diagnostic model with high predictive accuracy and area under the curve and principal component analysis metrics confirmed its robustness. The analysis of microbial markers, including Atopobium and Leptotrichia, highlighted the potential of the salivary microbiota as a non-invasive biomarker for the diagnosis and prognosis of glioma. Our findings highlight significant gender-specific disparities in the salivary microbiome of patients with glioma, offering new insights into the pathogenesis of glioma and paving the way for innovative diagnostic and therapeutic strategies. The use of saliva as a diagnostic fluid, given its ease of collection and non-invasive nature, holds immense promise for monitoring systemic health and the trajectory of disease. Future research should focus on investigating the underlying mechanisms by which the salivary microbiome influences the development of glioma and identifying potential microbiome-targeted therapies to enhance the management of glioma.

Ghost cells: Wilder Penfield and the characterization of glia and glial pathology, 1924–1932

ABSTRACT Wilder Penfield is known for his contributions to the structure–function relationship of the brain and for the surgical treatment of focal epilepsy. Less well known are his contributions to the study of glial cells and his investigation of their role in human neuropathology. Penfield learned the gold and silver methods for staining neurons, glial cells, and their projections from Charles Sherrington and Pío del Río-Hortega. He and his colleague William Cone established a laboratory for the study of glial cells and human neuropathology using metallic stains, initially at the Presbyterian Hospital in New York City in 1925, and then at the Montreal Neurological Institute in 1928. Penfield, Cone, and their research fellows, building on the findings of Río-Hortega, confirmed the existence of oligodendrocytes and their relationship with myelin, and investigated the putative mesodermal origin of microglia. They discovered the reaction of oligodendrocytes to pathological stressors, and the phagocytic activity of microglia in human gliomas. In this article, we argue that Penfield’s studies of astrocytes, oligodendrocytes, and microglia, and their responses to craniocerebral trauma, epilepsy, malignant brain tumors, and other pathologies of the central nervous system inaugurated a new era in clinical neurocytology and neuropathology.

Expanding TBCE-related phenotype-novel variant causing rigid spine, eosinophilia, neutropenia, and nocturnal hypoxemia.

We report three patients with the novel variant c.100 + 1G > A of the TBCE gene and describe the presented clinical phenotype in detail. We also systematically reviewed the literature for clinical similarities and dissimilarities among all known patients with pathogenic TBCE variants. The clinical phenotype observed in patients with pathogenic TBCE variants is broader than previously described. Homozygous carriers of the c.100 + 1G > A variant exhibit a markedly milder clinical course, with no deviations in the calcium-phosphate metabolism and central nervous system pathology in MRI studies. Additionally, two patients manifest highly specific symptoms such as a rigid spine, eosinophilia, neutropenia, and nocturnal hypoxemia. Furthermore, cryptorchidism was observed in male patients. The identification of the pathogenic c.100 + 1G > A variant has thus far been limited to patients of Central-Eastern European descent, suggesting a potential founder mutation in this population.

Metabolic Reprogramming of Astrocytes in Pathological Conditions: Implications for Neurodegenerative Diseases.

Astrocytes play a pivotal role in maintaining brain energy homeostasis, supporting neuronal function through glycolysis and lipid metabolism. This review explores the metabolic intricacies of astrocytes in both physiological and pathological conditions, highlighting their adaptive plasticity and diverse functions. Under normal conditions, astrocytes modulate synaptic activity, recycle neurotransmitters, and maintain the blood-brain barrier, ensuring a balanced energy supply and protection against oxidative stress. However, in response to central nervous system pathologies such as neurotrauma, stroke, infections, and neurodegenerative diseases like Alzheimer's and Huntington's disease, astrocytes undergo significant morphological, molecular, and metabolic changes. Reactive astrocytes upregulate glycolysis and fatty acid oxidation to meet increased energy demands, which can be protective in acute settings but may exacerbate chronic inflammation and disease progression. This review emphasizes the need for advanced molecular, genetic, and physiological tools to further understand astrocyte heterogeneity and their metabolic reprogramming in disease states.

Tumefactive Multiple Sclerosis: The Lethal Chameleon.

Tumefactive multiple sclerosis is an uncommon variant of multiple sclerosis that presents a substantial diagnostic challenge due to its potential to resemble the clinical and radiological characteristics of other central nervous system (CNS) pathologies, including neoplasms, granulomatous diseases, abscesses and vasculitis.Despite the fact that multimodal imaging studies may help narrow the differential diagnosis, a biopsy is often required to reach a definitive diagnosis and should not be delayed.Awareness of this condition among non-neurologists is critical since a timely and accurate diagnosis prompts aggressive immunomodulatory treatments that may delay a second demyelinating event or progression to clinically definite multiple sclerosis.

Effect of pseudorabies virus infection on NMDA receptor expression in mice and its role in immunosuppression

Pseudorabies virus (PRV), an α-herpesvirus, induces immunosuppression and can lead to severe neurological diseases. N-methyl-D-aspartate receptor (NMDAR), an important excitatory nerve receptor in the central nervous system, is linked to various nervous system pathologies. The link between NMDAR and PRV-induced neurological diseases has not been studied. In vivo studies revealed that PRV infection triggers a reduction in hippocampal NMDAR expression, mediated by inflammatory processes. Extensive hippocampal neuronal degeneration was found in mice on the 6th day by hematoxylin-eosin staining, which was strongly correlated with increased NMDAR protein expression. In vitro studies utilizing the CCK-8 assay demonstrated that treatment with an NMDAR antagonist significantly heightened the cytotoxic effects of PRV on T lymphocytes. Notably, NMDAR inhibition did not affect the replication ability of PRV. However, it facilitated the accumulation of pro-inflammatory cytokines in PRV-infected T cells and enhanced the transcription of the CD25 gene through the secretion of interleukin-2 (IL-2), consequently exacerbating immunosuppression. In this study, we found that NMDAR has functional activity in T lymphocytes and is crucial for the inflammatory and immune responses triggered by PRV infection. These discoveries highlight the significant role of NMDAR in PRV-induced neurological disease pathogenesis.