Alzheimer disease (AD) is a widespread neurodegenerative disorder. It is pathologically marked by the deposition of β-amyloid (Aβ) plaques and a high phosphorylation level of tau proteins, resulting in neurofibrillary tangle development, cognitive decline, and neuronal loss. Previous studies showed the correlation between AD and pyroptosis, an inflammasome-mediated programmed cell death. It was reported that Aβ and tau deposits may activate the NOD-like receptor pyrin domain-3 (NLRP3) and inflammasome-caspase-1-gasdermin D (GSDMD) pathway. This leads to cell membrane rupture and discharge of IL-1β and IL-18 cytokines that initiate neuroinflammation. However, there is still a lack of research on therapeutic approaches that target the pyroptotic pathway in AD. This review documents recent research on the regulatory function of miRNAs in regulating the NLRP3/caspase-1/GSDMD pathways and their potential to lessen pyroptosis-induced neuronal damage. We also address novel platforms for delivering antipyroptotic drugs and miRNA modulators across the blood-brain barrier using nanotechnology, such as engineered nanocarriers and exosome-like nanoparticles. These approaches have a promising therapeutic implication as potential treatment options for AD by combining molecular regulation and nanomedicine.

Adult-onset neuronal intranuclear inclusion disease (NIID) is a neurodegenerative disease that is pathologically characterized by eosinophilic hyaline intranuclear inclusions, mainly in astrocytes, and cerebral white matter degeneration. However, the pathogenesis underlying these neuropathological findings remains unclear. We previously reported an autopsy case of adult-onset NIID with characteristic perivascular findings. In that case, the perivascular areas were preserved despite cerebral white matter damage but dense glial fibrillary acidic protein-immunoreactive astrocytic processes were observed around the blood vessels. The present study examined 2 additional cases and confirmed that the above findings were common in patients with adult-onset NIID. To investigate the underlying pathophysiology behind these findings, immunohistochemistry was performed for proteins located in the astrocytic end-feet. In the cerebral white matter of all NIID cases, there was an altered distribution of aquaporin 4 (AQP4) with increased AQP4-immunopositive areas compared to control cases. These results suggest that the interaction between astrocytes and blood vessels, particularly involving water homeostasis, may be impaired in the cerebral white matter of patients with NIID.

Oncometabolite production plays a key role in the development and progression of isocitrate dehydrogenase-mutant gliomas. The aberrant gain-of-function activity of the mutant isocitrate dehydrogenase protein results in the production of the oncometabolite D-2-hydroxyglutarate, which in turn promotes DNA hypermethylation and gliomagenesis through several mechanisms. Rare gliomas in patients with fumarate hydratase deficiency syndrome share many morphologic and molecular features with isocitrate dehydrogenase-mutant gliomas, with the oncometabolites succinate and 2-succinocysteine similarly thought to promote global DNA hypermethylation. Like isocitrate dehydrogenase and fumarate hydratase, succinate dehydrogenase is also a member of the citric acid cycle that additionally participates in oxidative phosphorylation. While succinate dehydrogenase deficiency has been implicated in familial tumor syndromes, it has not yet been associated with glial neoplasms. Here we report 3 cases of diffuse glioma with succinate dehydrogenase deficiency that show many similarities with isocitrate dehydrogenase-mutant gliomas. We propose that succinate dehydrogenase deficiency with accumulation of the oncometabolite succinate can promote gliomagenesis in a similar manner as seen in isocitrate dehydrogenase-mutant and fumarate hydratase-deficient gliomas, and we discuss the proposed mechanisms that may lead to tumor formation.

Azetidine 2-carboxylic acid (Aze) is consumed by humans and can be misincorporated in place of proline (Pro) in myelin basic protein (MBP). In systemically treated mice Aze induced distinct oligodendroglial (OL) alterations mimicking those in multiple sclerosis (MS) patient normal-appearing white matter. Here, Aze induced an unfolded protein response (UPR), cytoplasmic MBP aggregation, apoptosis and tumor necrosis factor secretion in the human OL lineage MO13.3 cell line. These alterations were counteracted by equimolar Pro suggesting that they are due to Aze substitution for Pro in OL proteins. Gene set enrichment analysis demonstrated extensive Aze-induced alterations of cell cycle, cytoskeletal, organelle, transport, developmental, inflammation-associated and myelination pathways that are altered in OL in MS patients and in toxin and inflammatory MS animal models. These data provide mechanistic support for the hypothesis that Aze protein misincorporation during early life myelinogenesis might over time result in a progressive UPR culminating in a pro-inflammatory/immunomodulatory phenotype, intracytoplasmic MBP aggregation, accelerated senescence and apoptosis in OL. This could occur prior to and independent of an external immune stimulus such as a viral infection. Aze-induced pathological alterations might enhance subsequent antiviral and autoimmune responses and contribute to MS susceptibility, lesion pathogenesis, remyelination failure, neurodegeneration and clinical progression.

Primary cilia are non-motile sensory organelles that detect extracellular signals; disruptions in their functions are linked to neurodevelopmental disorders. Because cilia lengths can rapidly change in response to stressors, they are important for both plasticity and brain homeostasis. Accurate measurement of ciliary length is therefore essential but the absence of standardized methods and the variability introduced by different techniques can compromise measurement reliability and precision. To address this challenge, our study employed two distinct methods to estimate the length of primary cilia in hippocampal subregions in mice. We compared stereology-based 3D quantification, which is considered a methodological gold standard due to its unbiased sampling design and correction for tissue shrinkage, with 3D reconstruction to measure primary cilia length. 3D reconstruction imaging used a 100× oil-immersion objective. With neuronal cilia typically ∼2-10 µm long in hippocampus, a 1-µm z-step provided multiple optical sections per cilium thereby ensuring full structural visualization. Our findings show that both methods allow simple and equally precise measurements of neuronal primary cilia length in hippocampal subregions. Their strong agreement provides researchers with reliable tools for studying primary cilia on immunohistochemically stained sections and supports a consistent methodological framework for investigating cilia dynamics.

Microglia and astrocytes are essential glial cells in the CNS that play key roles in brain development, homeostasis, and disease. While immortalized cell lines are convenient, they lack the physiological relevance of primary cells, highlighting the need for reliable human-based isolation protocols. This systematic review synthesizes 21 studies describing methods for isolating and culturing primary human microglia and astrocytes from adult surgical resections, postmortem tissues, and fetal brains. Using the Human Brain Cell Atlas v1.0 single-nuclei RNA-Seq dataset and voxel-wise mapping on the MNI152 template, we provide a spatial transcriptomic context for region-specific glial isolation. We critically assess tissue dissociation techniques, enrichment strategies, and culture conditions, including substrate coatings and growth factors. Additionally, we summarize phenotypic and functional assays used for characterization including surface marker expression, phagocytosis, and cytokine profiling. Despite variability across protocols, we propose an optimized, spatially informed workflow to reproducibly isolate viable, pure glial populations from human brain tissues. This approach supports New Approach Methodologies and the 3Rs-Replacement, Reduction, and Refinement by promoting ethical, human-relevant in vitro models. Our framework advances glial cell-based systems, improving the translational relevance of neurodegenerative and neuroinflammatory disease research and aligns with multiple United Nations Sustainable Development Goals through responsible scientific practices.

Conventional CSF markers often fail to distinguish immune-mediated neurologic disorders (IMNDs) from non-immune-mediated neurologic disorders (N-IMNDs). We performed multiparametric flow cytometric profiling of CSF T-cell developmental subsets in 37 IMND patients and 10 N-IMND controls to identify IMND-associated T-cell signatures. CSF CD8+ T-cells were detectable in 86% (32/37) of IMND patients versus 0% (0/10) of N-IMND controls (Padj < .001). Among CD8+ T-cell-positive IMND cases, effector memory (CD45RA-CCR7-, median, 65.0%; IQR, 45.5%-73.5%) and terminally differentiated effector memory T-cells (TEMRA, CD45RA+CCR7-, median, 35.0%; IQR, 0%-49.5%) predominated. Hierarchical clustering demonstrated significant separation between IMND and N-IMND driven by CD8+ T-cell subset profiles (R2 = 0.165, P = .001), whereas CD4+ T-cell subsets showed no disease-associated clustering. Paired blood-CSF analysis in 6 treatment-naïve IMND patients revealed compartmentalized enrichment of CD8+ effector memory (blood median 19.2%; IQR, 6.4%-26.9%; CSF median 47.3%; IQR, 42.2%-53.7%; P = .031), confirming CNS-restricted CD8+ T-cell activation. These findings identify CSF CD8+ effector memory profiles as a potential biomarker distinguishing IMNDs from N-IMNDs that may complement conventional biomarkers for CNS autoimmunity.

Convincing evidence suggests that FoxO signaling (FS) dysfunction is associated with cancer progression and tumorigenesis but its effect on the tumor microenvironment (TME) and immunotherapy response remains unclear. Here, we retrieved FS-related genes from the KEGG database, first analyzing their differential expression in 31 TCGA cancer types with matched Genotype-Tissue Expression (GTEx) normal tissue data. We then calculated FS scores via ssGSEA for 33 TCGA cancer types, systematically exploring their prognostic value and correlations with TME characteristics and immunotherapy response. High FS scores were consistently associated with an immunosuppressive TME and poorer OS across multiple tumor types. Analysis of the IMvigor210 immunotherapy cohort further revealed elevated FS scores correlated with anti-PD-1 treatment resistance. Focusing on gliomas, we identified FS-based molecular subtypes and constructed a PCA score that robustly predicted glioma prognosis and immune checkpoint inhibitor response. External validation was achieved in independent CGGA and GEO cohorts. Our findings indicate that FS is a key modulator of the immunosuppressive TME and support FS and PCA scores as potential prognostic and immunotherapeutic biomarkers for gliomas with their clinical utility pending experimental validation.