Search Results (578)

Epidermal growth factor receptor variant III (EGFRvIII) is a constitutively active EGFR deletion variant found in a subset of glioblastomas (GB). Its association with stem-like tumor populations is well documented, but the outcome of EGFRvIII expression may vary with the developmental and molecular state of the recipient cell. Here, we used human induced pluripotent stem cell (iPSC)-derived, glial fibrillary acidic protein (GFAP)-negative-induced neural stem cells (iNSCs) to explore how this receptor variant affects a defined neural stem/progenitor background. EGFRvIII was introduced either constitutively by lentiviral transduction or through a doxycycline-responsive Tet-On system. Both experimental approaches were associated with remodeling of the neural stem/progenitor marker profile, with reduced SRY-box transcription factor 2 (SOX2) expression in the inducible model and significant reductions in both SOX2 and nestin in the constitutive model. Constitutive expression was also associated with increased senescence-associated β-galactosidase (SA-β-Gal) activity, while doxycycline induction produced a distinct change in cell-number dynamics at low doxycycline concentration. Thus, in this experimental setting, EGFRvIII was linked to substantial remodeling of the SOX2+/nestin+ marker profile. These observations do not define a differentiation pathway, prove cellular senescence or malignant transformation, or identify the cell of origin of EGFRvIII-positive GB. Rather, they support the view that the cellular response to EGFRvIII should be considered in relation to the specific neural-glioblastoma precursor context. Full article

Olfactory dysfunction is an early non-cognitive feature of Alzheimer’s disease (AD), but smell impairment has traditionally been used mainly as a behavioral marker. This review examines the emerging use of the olfactory cleft as an accessible source of living neuronal, epithelial, progenitor, and immune cells for studying AD pathobiology. Histopathological and patient-derived culture studies have reported amyloid-β, tau, oxidative-stress, mitochondrial, biometal, and transcriptional abnormalities in olfactory tissue. More recent endoscopically guided brush sampling with single-cell profiling has identified activated memory CD8 T-cell states, inflammatory myeloid programs, and neuronal metabolic changes, including in cognitively unimpaired individuals with abnormal cerebrospinal-fluid amyloid biomarkers. These findings support olfactory-cleft sampling as a research platform for investigating early neural–immune changes, but current evidence is based on small, largely cross-sectional cohorts and does not establish disease specificity, causality, or prognostic utility. Longitudinal multicenter studies integrating olfactory-tissue profiling with established fluid, imaging, genetic, cognitive, and olfactory biomarkers are required before clinical translation. Full article

Pre-B-cell leukemia transcription factor 3 (PBX3) is a TALE homeodomain protein involved in neural development, but its function in oligodendrocyte (OL) differentiation has remained unexplored. Here, we show that PBX3 expression is dynamically regulated during OL lineage progression, with peak expression in the corpus callosum at P14, corresponding to the onset of active myelination. In cultured primary oligodendrocyte precursor cells (OPCs), PBX3 expression peaked at OL-1DIV, an early stage of in vitro differentiation. Using OL lineage-specific Pbx3 conditional knockout mice, we found that Pbx3 deletion reduced the density of SOX10⁺ OL lineage cells and CC1⁺ mature OLs in the corpus callosum at P14 and P27, accompanied by decreased MBP expression. Notably, these deficits were largely resolved by P50, indicating an age-dependent rather than absolute requirement for PBX3. EdU labeling revealed reduced OPC proliferation in Pbx3 cKO mice, though the Olig1-Cre driver used for conditional deletion is active in early neural progenitors, and thus contributions from reduced OPC specification or generation cannot be excluded. Consistently, siRNA-mediated Pbx3 knockdown in primary OPCs impaired differentiation and reduced MBP expression in vitro. Collectively, our findings identify PBX3 as a positive regulator of OL differentiation during early postnatal development, with a temporally restricted requirement, and provide insights into the transcriptional control of CNS myelination. Full article

Climate change is increasing the frequency and intensity of extreme heat events, raising concern about prenatal thermal exposure as a potential risk factor for fetal brain development and offspring neurodevelopment. This systematic review aimed to synthesize evidence on prenatal heat exposure, placental inflammatory or stress-response pathways, and fetal or offspring neurodevelopmental outcomes, while evaluating the placenta–brain axis as a proposed mechanistic hypothesis rather than an established causal pathway. A systematic literature search was conducted in PubMed/MEDLINE, Scopus, Web of Science, Google Scholar, and Embase from database inception to 30 June 2026. Human observational studies, animal experiments, and in vitro mechanistic studies were included when they examined prenatal thermal exposure in relation to either placental function and stress-response mechanisms or fetal-brain and offspring neurodevelopmental outcomes. Ambient environmental heat, infectious fever, behavioral or exogenous heat exposure, experimental maternal hyperthermia, and direct cellular or organoid thermal stimulation were considered separately because these exposures are not biologically equivalent. Across the included studies, distinct prenatal thermal exposures—including ambient environmental heat, infectious fever, behavioral or exogenous heating, and experimentally induced hyperthermia—were associated with congenital central nervous system anomalies, including neural tube defects, as well as later outcomes such as neurodevelopmental delay, language impairment, autism spectrum disorder, cerebral palsy, and altered child-brain morphology. The strongest and most consistent early-pregnancy signal concerned neural tube defects during the periconceptional and neurulation periods, whereas evidence for later neurodevelopmental outcomes identified more heterogeneous susceptibility windows across gestation. Experimental evidence suggested alterations in placental barrier function, glucocorticoid and serotonin-related signaling, inflammatory and oxidative pathways, myelination, apoptosis, and neural-progenitor development. However, only one included experimental study jointly assessed maternal heat stress, placental alterations, and fetal-brain-related outcomes, while the human studies did not measure placental mediators or perform mediation analyses. Evidence from non-heat inflammatory studies therefore provides only indirect mechanistic context. Overall, prenatal heat exposure may contribute to neurodevelopmental vulnerability through multiple direct and indirect pathways, including a biologically plausible but unproven placenta–brain framework. Prospective studies integrating individual-level heat assessment, placental biomarkers, standardized fetal-brain imaging, and longitudinal neurodevelopmental follow-up are required to test this hypothesis. Full article

Background: Glioblastoma is a primary aggressive brain tumor, with an average survival rate of ~14.6 months. The low therapeutic benefit of current treatments is in part due to glioblastoma-initiating cells hijacking microglia/macrophages to support tumor growth, prompting the development of multitargeted therapeutic approaches. One such therapeutic target is transcription factor Nrf2. High Nrf2 activity is associated with high-grade tumors, and high Nrf2 levels in microglia/macrophages lead to polarization toward an immunosuppressive profile, supporting glioblastoma progression and therapy resistance. Interestingly, however, sulforaphane (SFN), an isothiocyanate found in cruciferous vegetables and a potent Nrf2 activator, has anti-carcinogenic effects in multiple animal models. Methods: We utilized the zebrafish glioblastoma initiation model of human AKT1 overexpression in neuronal progenitors to capture the intermediate progenitor-cell-like state of glioblastoma-initiating/pre-neoplastic cells and evaluated the therapeutic potential of SFN and VVD130037, an Nrf2 inhibitor currently in clinical trials. Results: Initial findings suggest that SFN, individually and in combination with VVD130037, had the potential to decrease the levels of AKT1. Surprisingly, VVD130037 tended to increase AKT1. The pAKT1 levels also increased in Nrf2-deficient human cells. Moreover, failure to activate Nrf2 in neural progenitors in response to SFN, while a preliminary observation that warrants further investigation, suggests that the decrease in AKT1 was not potentially mediated by Nrf2 activation. The combined effect of SFN and VVD130037 on AKT1 was particularly strong in irf8-/- mutant larvae, which lack a microglia/macrophage population, indicating the existence of a non-tumorigenic cell population(s) sensitive to changes in Nrf2 activity. Conclusions: AKT1 inhibition in glioblastoma-initiating cells by the phytochemical SFN, combined with Nrf2 inhibition in the surrounding cells, may impede glioma progression. Full article

Ruminants are unique among living mammals in possessing paired bony cranial appendages in the form of horns, pronghorns, antlers, or ossicones. This review summarizes current knowledge on the structure, development, function, and evolution of these appendages and integrates recent findings from genomics, transcriptomics, and single-cell analyses. Two competing hypotheses have been proposed to explain their origin. According to the independent-origin hypothesis, horns, pronghorns, antlers, and ossicones evolved separately in different pecoran lineages, possibly through repeated recruitment of similar developmental capacities of the frontal region of the skull. According to the common-origin hypothesis, these appendages derive from a single ancestral osseous cranial structure that was subsequently modified in different lineages. Comparative anatomy and developmental data reveal major differences among the four types of appendages, including dermally ossifying horn cores in bovids, annually regenerated antlers arising from frontal bone pedicles in cervids, deciduous keratin sheaths in pronghorns, and skin-covered ossicones in giraffids. The fossil record does not currently resolve these hypotheses, because the main appendage types are first documented within a relatively short early Miocene interval and transitional forms remain unknown. In contrast, molecular and cellular studies identify shared developmental pathways, cranial neural crest-derived progenitors, and conserved regulatory genes, including RXFP2, ALX1, SOX9, and components of Wnt signaling, which are consistent with a shared developmental module. We conclude that the homology of pecoran cranial appendages remains unresolved and that further paleontological, developmental, and comparative molecular studies are required to determine whether these structures share a common evolutionary origin or instead represent convergent recruitment of similar developmental programs. Full article

Posterior axis development during mammalian embryogenesis is driven by transient progenitor states that give rise to neural and mesodermal lineages, including neuromesodermal progenitors (NMPs). In vitro derivation of posterior progenitor populations from human pluripotent stem cells (hPSCs) has relied on modulation of Wnt and FGF signaling; however, these approaches frequently generate heterogeneous and unstable cell populations. Here, we investigated whether sodium butyrate (NaB) supplementation could promote a posteriorly biased intermediate state without extensive extracellular signaling control. We show that NaB, a histone deacetylase inhibitor, promotes the induction of posterior pre-neural progenitors (PNPs) characterized by co-expression of CDX2 and SOX2, together with suppression of SOX1. Transcriptomic analyses revealed that NaB-treated cells exhibit a posteriorly enriched PNPs with restrained anterior neural differentiation, transient early TBXT induction, and progressive activation of posterior HOX genes, consistent with an incompletely caudalized intermediate rather than a fully specified NMP population. Importantly, these PNPs remained responsive to canonical neural tube patterning cues, including retinoic acid and smoothened agonists, enabling further differentiation toward ventral spinal cord lineages. Collectively, our findings demonstrate that NaB supplementation supports posterior PNPs from hPSCs, providing a simple and reproducible platform for modeling early posterior neural development in vitro. Full article

The tree shrew is a small mammal characterized by a short gestation period, a relatively short lifespan, and low maintenance costs. It exhibits a close genetic relationship with primates and humans. The tree shrew possesses an eight-layered neocortex, limited cortical gyrification, an expanded subventricular zone, and sensory, visual, and motor cortices that resemble those of primates, along with comparable neurotransmitter systems, cognitive potential, and neural flexibility. These features render it a promising animal model for neurological disease research. A comprehensive understanding of its brain morphology, neural projections, neural circuits, and neuronal diversity is crucial both in terms of elucidating normal brain function and in order to establish this species as a reliable model in investigations of the mechanisms underlying neural injury and neurodegenerative diseases. Currently, studies on tree shrew brain development remain limited. This review presents a comprehensive summary of two-dimensional (2D) and three-dimensional (3D) comparative anatomical studies based on brain region localization, histological section staining, and MRI-derived brain imaging data in the tree shrew. It also analyzes the developmental characteristics of neural progenitor cells in this species. Furthermore, the review compares brain atlases of mice, non-human primates (NHPs), humans, and tree shrews generated using single-cell sequencing and spatial transcriptomic technologies. Finally, it outlines future research directions that emphasize the importance of integrating morphology and functional neuroimaging data with multi-omics data to construct a multimodal, four-dimensional (4D) brain development atlas of the tree shrew. Full article

Cumulative reports of psychiatric and neurological outcomes due to synthetic cathinones continue to raise public concern. However, the understanding of the neurotoxic mechanism of action is still poorly understood, particularly for the under-explored αPHP, one of the main MDPV derivatives. In particular, the effects of this synthetic drug on neural stem/progenitor cell cultures are still unknown. Therefore, in the proposed in vitro study, the effects of increasing αPHP concentrations (50–2000 μM) on cell morphology, neuronal/glial differentiation, cell death pathways, and ultrastructure have been evaluated after exposure in murine 2D NSPCs and 3D neurospheres using complementary techniques, i.e., phase contrast microscopy, immunocytochemistry, confocal microscopy, and transmission electron microscopy. We observed that αPHP was able to induce a dose-dependent neurotoxic and neuromodulatory effect in murine 2D NSPC cultures and a 3D neurosphere model, affecting neuronal/glial differentiation, activating the apoptotic pathway, and inducing morphological and ultrastructural changes. The present study could pave the way for a broadened knowledge of synthetic cathinone (SCs) toxicology, needed to establish the right treatment for novel psychoactive substance (NPS) exposure and the possible consequences for public health. Full article

Huntington’s disease (HD) has traditionally been conceptualized as a neuron-centric disorder primarily attributed to cell-autonomous toxicity of mutant huntingtin (mHTT) in striatal medium spiny neurons. However, this framework inadequately explains the prolonged presymptomatic phase, selective network vulnerability, early non-motor manifestations, and limited success of neuron-targeted therapeutic interventions. Accumulating evidence from molecular biology, transcriptomics, neuroimaging, and preclinical therapeutics supports a reframing of HD as a disorder of neuroglial systems dysfunction. We synthesize data demonstrating that astrocytes, microglia, and oligodendrocyte lineage cells are not passive bystanders but play direct and interactive roles in HD pathogenesis through defined molecular mechanisms. Expression of mHTT in glial populations impairs synaptic homeostasis, metabolic coupling, immune resolution, and myelin integrity, generating self-amplifying pathological feedback loops that destabilize neural circuits long before overt neuronal death. Critically, we evaluate glial replacement therapy as a potential disease-modifying strategy. Preclinical studies demonstrate that transplantation of healthy human glial progenitor cells substantially ameliorates motor, cognitive, and neuropathological deficits in multiple HD models through oligodendroglial remyelination and lactate-mediated metabolic support, despite persistent neuronal mHTT expression. Effective HD therapy will likely require strategies that jointly target the genetic cause and the dysfunctional neuroglial microenvironment. By integrating systems neuroscience with glial biology and translational strategy, this review defines a neuroglial framework for HD that opens a plausible path toward meaningful disease modification and positions HD as a model disorder for glial-centric interventions in neurodegeneration. Full article

Neuropeptide Y [NPY; encoded by the NPY gene] is a widely expressed 36-amino-acid neuropeptide that regulates neuronal function, vascular regulation, and immune regulation; its role in glioblastoma [GBM] remains incompletely characterized. We performed an integrative in silico multi-scale transcriptomic analysis combining bulk RNA-sequencing of IDH-wildtype GBM [n = 169] and lower-grade glioma [n = 510] surgical resections from TCGA, normal cortical tissue from GTEx [n = 207], and four independent GEO validation cohorts of surgical GBM and non-tumor brain specimens [GSE4290, GSE50161, GSE131928 scRNA-seq of ~20,426 cells from 28 patients, and GSE194329 10X Visium spatial transcriptomics from five patients], along with survival modeling, pathway enrichment, single-cell RNA sequencing, spatial transcriptomics, and cell–cell communication analysis. NPY and its principal receptor, NPY1R, were significantly downregulated in GBM, while genes associated with hypoxia, angiogenesis, invasion, and immune suppression were upregulated. Single-cell analysis showed that NPY-axis transcript expression was elevated in neural progenitor-like populations. In contrast, hypoxia and metabolic programs were concentrated in mesenchymal tumors and stromal compartments, indicating distinct cellular contexts. Spatial analysis revealed a weak and heterogeneous relationship between NPY and hypoxia signatures, with substantial inter-patient variability and no significant global spatial cross-correlation. These findings indicate that loss of NPY signaling is a consistent feature of GBM and is associated with hypoxia-driven tumor states, while the spatial relationship between NPY and hypoxia appears weak, heterogeneous, and patient-specific. Full article

Numerous central nervous system pathological conditions involve blood–brain barrier (BBB) disruption and the egress of immune cells in the brain. Controlling immune cell transmigration into the brain represents a potential therapeutic target. This study describes the application of a 3D human BBB spheroidal model that consists of six major brain cell types to test the transmigration of immune cells under normal and pathological conditions of inflammation and ischemia–reperfusion injury (IRI). The cell types in the BBB organoid include brain microvascular endothelial cells (HBMVECs) and pericytes at the spheroids’ surface, surrounding a core of astrocytes, microglia, oligodendrocytes, and neural progenitor cells. The model recapitulates the interaction of CD4⁺ T-cells and immunomodulators with HBMVECs at the BBB including changes in cell adhesion molecules expressed on their surface. This study demonstrated that the human 3D BBB model recapitulates many features of the barrier under normal and pathological conditions of inflammation and hypoxia-reperfusion injury. Proinflammatory cytokines and hypoxia disrupt the barrier and increase its permeability, decreasing the expression of tight junctions. Proinflammatory cytokines and reperfusion increase the expression of cell adhesion molecules and increase immune cell transmigration. Immune cell transmigration could be reduced with anti-cell adhesion molecule antibodies, further validating the model for studying neuroimmune interactions and for conducting high-throughput screening of therapeutic targets that modulate immune cell transmigration into the brain. Full article

Intercellular communication is crucial for the coordination of skeletal muscle development. However, the intricate signaling networks that regulate chicken myogenesis are not yet fully elucidated. In this study, we utilized CellChat analysis on single-cell and single-nucleus RNA sequencing data to systematically delineate cell–cell communication patterns across five critical developmental stages of chicken skeletal muscle: embryonic day 4 (E4), day 6 (E6), day 12 (E12), day 18 (E18), and post-hatch day 30 (P30). Our findings indicate that communication architectures are highly stage-specific, with mesenchymal cells acting as the predominant signaling hub during the early embryonic stages (E4–E6), whereas fibro-adipogenic progenitors become the principal communicators during mid-to-late embryogenesis (E12–E18). At E4, the communication network was relatively simple, comprising 51 ligand–receptor pairs primarily involving the neural cell adhesion molecule, slit guidance ligand, and midkine (MK) signaling pathways between myogenic progenitors and mesenchymal cells. By E6, the network had expanded significantly, encompassing 6237 ligand–receptor pairs across 51 signaling pathways, which coincided with the emergence of multiple myogenic lineages. Peak communication complexity was observed at E12, characterized by 11,675 ligand–receptor pairs and 61 signaling pathways, reflecting the secondary wave of myogenesis. Comparative analysis across developmental stages revealed key signaling transitions: the pleiotrophin and MK pathways were predominantly active during the early phase of myogenic commitment (E4–E6), whereas the collagen, laminin, and adhesion G protein-coupled receptor L pathways were more prominent during the secondary myogenesis phase (E6–E12). Notably, a significant shift in communication patterns was observed from E12 to E18, marked by a reduction in developmental pathway signaling and an increase in immune-related communications. By P30, the communication network had stabilized into a homeostatic state, centered on interactions among myofibers, stromal cells, and the vascular system. This comprehensive atlas of intercellular communication offers novel insights into the signaling dynamics underpinning chicken skeletal muscle development. Full article

Copy number variants (CNVs) are genomic rearrangements that carry a substantial risk for neurodevelopmental and neuropsychiatric disorders. Among these, recurrent deletions and duplications at the 16p11.2 locus are robustly associated with autism spectrum disorders, schizophrenia, epilepsy, and related conditions, yet also display marked variability in penetrance and phenotypic expression. Accumulating evidence indicates that 16p11.2 gene dosage influences multiple stages of brain development, from early progenitor dynamics and neuronal migration to synaptic formation, refinement, and plasticity. However, how disruptions across these processes are integrated over time, and how they relate to the observed variability and incomplete penetrance, remains poorly understood. In this review, we summarize the current evidence on the impact of 16p11.2 CNVs on brain development, focusing on cellular and circuit-level processes that shape neural connectivity. We discuss how gene dosage imbalance influences early developmental trajectories, synaptic formation and pruning, interneuron maturation, and activity-dependent plasticity, and consider how these processes interact across developmental stages. We suggest a conceptual framework wherein 16p11.2 CNVs do not impose fixed pathogenic outcomes, but rather they contribute towards developmental constraints that shape the timing and stability of neural circuit development. Consequently, these constraints increase vulnerability to neurodevelopmental and psychiatric outcomes in a context-dependent manner. Full article

Accumulation of aggregated amyloid beta (Aβ) species is a defining pathological hallmark of Alzheimer’s disease and is associated with extensive neuronal structural abnormalities. Mild cognitive impairment (MCI), a transitional stage between normal aging and the onset of dementia, is thought to represent an early phase of this pathological continuum. Studies at the cellular level suggest that the conditions impair the maintenance of established neuronal processes/networks and restrict their capacity for elongation or re-elongation. They may also attenuate the activation and process extension of quiescent neural progenitor or stem-like cells. These early cellular changes precede overt neurodegeneration in neural tissue and are likely to contribute to cognitive decline. They highlight the importance of in vitro models for identifying molecular targets involved in recovery from disease. In this study, we investigated the effects of aggregated Aβ (25–35) on neuronal process elongation and associated intracellular events in the N1E-115 cell line, a widely used model of neuronal differentiation. Addition of aggregated Aβ to cultured N1E-115 cells attenuated process elongation in a concentration-dependent manner. This morphological impairment was accompanied by decreased expression of neuronal differentiation markers. In contrast, at the half-maximal inhibitory concentration for process elongation, long-term cultured cells did not exhibit apparent process retraction or degenerative morphology. This mild but progressive impairment, without extensive cell death, is consistent with the cellular features of early-stage conditions rather than advanced Alzheimer’s pathologies. Similar results were observed in primary cortical neurons. Aβ also decreased the level of GTP-bound Ras and phosphorylation of the downstream mitogen-activated protein kinase/extracellular signal-regulated kinase (MAPK/ERK). Furthermore, treatment with hesperetin, a bioactive flavonoid compound, recovered the Aβ-induced inhibition of neuronal process elongation. Hesperetin also restored Ras and MAPK/ERK states, suggesting that its effects are associated, at least in part, with modulation of signaling through Ras and MAPK/ERK. Our findings suggest that hesperetin may serve as a useful molecular probe for modulating early cellular responses associated with Alzheimer’s disease-related pathology. This in vitro model might serve as a useful platform for investigating the molecular target candidates involved in recovery from nervous system disorders. Full article