Search Results (56)

Introduction: Glioblastoma (GBM) is the most aggressive primary tumor of the central nervous system and is highly resistant to temozolomide (TMZ). Rutin is a potent antioxidant with immunomodulatory and anti-glioma effects in vitro, although its mechanisms of action remain incompletely understood. This study investigated the effects of rutin on morphology, viability, redox balance, and pro-tumoral signaling in GBM 2D cultures and 3D spheroids, as well as its association with TMZ sensitivity. Methods: GL15 and U343 human GBM cell lines and primary astrocytes were treated with rutin (5–30 μM) and/or TMZ (125–4000 μM). Cell metabolic activity and viability were assessed by MTT, PI/DiOC18(3) or PI/Hoechst. Cell migration was assessed from spheroid-derived cells, and extracellular matrix (ECM) components (fibronectin and laminin) were evaluated by immunofluorescence. Intracellular reactive oxygen species (ROS) were measured by DCFH-DA fluorescence. IL-6, STAT3, NOS2, and IDO1 gene expression were determined by RT-qPCR, and protein expression of MMP2, fibronectin, STAT3, PI3K, and AKT by Western blotting. Nitric oxide (NO) and L-kynurenine levels were quantified in the supernatant by colorimetric assays. Results: Rutin reduced cell viability and enhanced TMZ cytotoxicity in both 2D and 3D cultures, while exerting selective effects by increasing metabolic activity and attenuating TMZ-induced effects in non-tumoral primary astrocytes. In 3D spheroids, rutin affected structural organization and reduced spheroid-derived cell migration, accompanied by changes in ECM components, including MMP2, fibronectin, and laminin. Rutin decreased intracellular ROS levels and suppressed the TMZ-induced increase in ROS and NOS signaling. These effects were accompanied by modulation of IL-6/STAT3 signaling, along with reduced STAT3, PI3K, and AKT protein levels. Rutin also modulated immunometabolic parameters, including extracellular L-kynurenine and nitric oxide levels, and enhanced TMZ responsiveness following pre-sensitization. Conclusions: Rutin enhances TMZ responsiveness by modulating interconnected pro-tumoral mechanisms, including redox balance, pro-survival signaling, ECM remodeling and migratory behavior, and immunometabolic pathways linked to chemoresistance, supporting its potential as an adjuvant therapeutic strategy. Full article

Astrocytes play a crucial role in maintaining neuronal microenvironment homeostasis and regulating synaptic plasticity within the hippocampus. Magnoflorine (MGN), a naturally occurring isoquinoline alkaloid, has demonstrated biological activity in the central nervous system. However, its effects on astroglial cells remain poorly understood. The present study aimed to evaluate the impact of acute and chronic administration of MGN (10 and 20 mg/kg body weight) on the morphology and morphometric parameters of GFAP-positive astrocytes in the CA1 field of the mouse hippocampus. Immunohistochemical and morphometric analyses were performed in the oriens layer (SO), pyramidal layer (SP), radiate layer (SR), and lacunose-molecular layer (SLM). MGN significantly modulated astrocyte density, cell size, and the number of processes in a dose-, time-, and layer-dependent manner. A heterogeneous and layer-specific astroglial response was particularly evident following chronic administration of the tested compound. Together with the observed lack of significant differences in analysed parameters, decreases were mainly detected after administration of the low MGN dose, whereas the 20 mg/kg dose induced primarily increased structural complexity. Thus, the direction of changes was not uniform across all layers. The most prominent changes were detected in the SLM layer. Overall, MGN modulated astrocyte morphology and reactivity in a context-dependent manner. These findings indicate a modulatory influence of MGN on astroglial structural plasticity rather than a uniform directional effect. Although the observed changes may be associated with alterations in astroglia-mediated mechanisms involved in maintaining neuronal homeostasis and responses to stress, their functional significance requires further investigation. Full article

Astrocytes are now recognized as active and essential participants in neural circuit function, extending far beyond their traditional roles as passive support cells. Emerging evidence highlights their critical involvement in synaptic modulation, information processing, and complex behaviors, making them key targets for understanding cognitive dysfunction in psychiatric disorders. This narrative review synthesizes current findings from rodent models to elucidate the relationship between astrocytic networks and multidomain cognitive performance. We first outline the morphological and physiological features of astrocytes, followed by a comprehensive overview of the modern experimental toolkit, including observational markers and advanced interventional strategies. Next, we evaluate commonly used behavioral assays that capture distinct cognitive domains, ranging from basic spatial and recognition memory to higher-order executive functions, cognitive flexibility, and social cognition. By integrating recent experimental evidence, we detail the specific mechanistic pathways, such as intracellular calcium signaling, gliotransmission, and neuroinflammatory reactivity, through which astrocytes directly govern these cognitive processes. Finally, we highlight critical knowledge gaps stemming from methodological limitations, arguing for the integration of more ethologically relevant, high-throughput behavioral tasks alongside highly specific targeting tools to better capture the functional heterogeneity of astrocytes in cognitive health and disease. Full article

Astrocytes undergo pronounced reactivity during traumatic brain injury (TBI); however, the temporal dynamics of this response and the signaling mechanisms regulating astrocyte proliferation remain incompletely defined. In this study, we characterized the spatiotemporal profile of astrocyte reactivity and proliferation in the hippocampus during TBI and investigated the involvement of mammalian target of rapamycin complex 1 (mTORC1) signaling in these processes. Using a mouse model of TBI, we found that injury triggered a rapid astrocytic response in the hippocampus, characterized by increased glial fibrillary acidic protein (GFAP) expression and morphological hypertrophy as early as 4 h post-injury. Astrocyte proliferation emerged subsequently, peaked during the acute phase (48 and 72 h), and declined to baseline levels at 7 days post-trauma, indicating a transient proliferative response during TBI. Concurrently, mTORC1 signaling was robustly activated in reactive astrocytes in the hippocampus and was specifically associated with proliferative reactive astrocytes during injury. Pharmacological inhibition of mTORC1 signaling with rapamycin significantly reduced reactive astrocyte proliferation during TBI without altering astrocytic hypertrophy. Together, these findings demonstrate that TBI induces a rapid but transient astrocyte activation and proliferation response in the hippocampus and that mTORC1 activation is required for the proliferation, but not the hypertrophic activation, of reactive astrocytes during traumatic brain injury. Full article

Background: Apigenin, as a flavonoid, can be protective against oxidative damage in hypoxic events due to its antioxidant properties. Here, we have investigated the neuroprotective effects of apigenin in an ex vivo model of ischemic damage, using cerebellar slices from postnatal day (P)8–12 reporter mice to identify oligodendrocytes (SOX10-EGFP) and astrocytes (GFAP-EGFP). Methods: Apigenin (10 and 20 μM) was administered preventively at 60 min prior to and during inducing ischemic damage by oxygen and glucose deprivation (OGD); controls were maintained with glucose and normoxia (OGN). Results: OGD induced a marked retraction of oligodendroglial processes without reducing the oligodendrocyte number. This structural disruption was prevented by apigenin; notably, 10 μM apigenin blocked process retraction, whereas 20 μM did not, indicating a dose-dependent effect on the oligodendroglial morphology. Consistent with this, MBP and NF70 immunofluorescence analyses of axonal myelination demonstrated that OGD caused a significant loss of myelin sheaths, and this was prevented by pre-treatment with apigenin. In addition, apigenin prevented astrocyte reactivity induced by OGD, as assessed by increased GFAP-EGFP expression and decreased expression of glutamine synthetase. Moreover, immunofluorescence for calbindin indicated that apigenin protected Purkinje neurons from ischemic damage. Conclusions: These results demonstrate that apigenin is neuroprotective in ischemia and this is associated with modulation of astrocyte reactivity and maintenance of oligodendrocyte and myelin integrity. Full article

Retinal astrocytes reside mainly in the nerve fiber layer and are central to shaping retinal vessels and maintaining neurovascular balance. Derived from the optic nerve head, they spread across the inner retina to form a meshwork that both supports and instructs the emerging superficial vascular plexus. Immature astrocytes supply vascular endothelial growth factor-A(VEGF-A) to guide endothelial sprouting, while signals from growing vessels promote astrocyte maturation and strengthen the blood–retinal barrier. In disorders such as diabetic retinopathy and neovascular age-related macular degeneration, these cells show marked plasticity. Reactive astrogliosis can sustain VEGF and inflammation, favoring fragile, leaky neovessels, whereas alternative astrocyte states help reinforce barrier function and release anti-angiogenic factors. Located at the core of the neurovascular unit, astrocytes communicate continuously with endothelial cells, pericytes and neurons. This review integrates data from single-cell profiling and advanced imaging to outline astrocyte development, morphology and key signaling pathways (VEGF, PDGF, Wnt/Norrin, Eph/ephrin), and considers how tuning astrocyte polarization might be exploited to preserve retinal vascular integrity. Full article

Spinal cord injury (SCI) remains a major clinical challenge due to the limited regenerative capacity of the central nervous system (CNS). Effective scaffolds for repair must combine mechanical compatibility with host tissue, controlled degradation matching the time course of regeneration, and microarchitectural features that promote neuronal survival. Electrospun nanofibrous scaffolds mimic the structural and mechanical features of the extracellular matrix, providing critical cues for neuronal adhesion and glial modulation in neural regeneration. Here, we fabricated biodegradable poly(lactic acid)/poly(ε-caprolactone) (PLA/PCL) scaffolds using a dichloromethane/tetrahydrofuran (DCM/THF) solvent system to induce surface porosity via solvent-driven phase separation. The DCM/THF solvent system formulation produced nanofibers with porous surfaces and increased area for cell interaction. PLA/PCL scaffolds showed a Young’s modulus of ~26 MPa and sustained degradation, particularly under oxidative conditions simulating the post-injury microenvironment. In vitro, these scaffolds enhanced neuronal density up to fivefold and maintained ~80% viability over 10 days in primary neuron–glia cultures. Morphometric analysis revealed that DCM/THF-based scaffolds supported astrocytes with preserved process complexity and reduced circularity, indicative of a less reactive morphology. In contrast, scaffolds fabricated with 1,1,1,3,3,3-hexafluoro-2-propanol (HFIP) displayed reduced bioactivity and promoted morphological features associated with astrocyte reactivity, including cell rounding and process retraction. These findings demonstrate that solvent-driven control of scaffold microarchitecture is a powerful strategy to enhance neuronal integration and modulate glial morphology, positioning DCM/THF-processed PLA/PCL scaffolds as a promising platform for CNS tissue engineering. Full article

Background/Objective: Parkinson’s disease (PD) has long been viewed from a neurocentric perspective; however, increasing evidence indicates that glial dysfunction also contributes to dopaminergic neurodegeneration. Although neurotoxic glial phenotypes have been described in amyotrophic lateral sclerosis and Alzheimer’s disease in vivo models, it remains unclear whether similar states arise in the pathological milieu of PD. This study aimed to determine whether glial cells with intrinsic neurotoxic properties emerge in the substantia nigra pars compacta (SNpc) in a PD context. Methods: The classical 6-hydroxydopamine rat model was used to obtain glial cultures from the ipsilateral, toxin-damaged SNpc. These cultures were characterized by quantifying cell number and morphology, as well as by assessing the expression of glial markers. Their neurotoxic potential was evaluated in vitro through co-cultures with PC12 cells, and in vivo by transplanting the isolated cells into the SNpc of naïve rats. Assessments included PC12 cell survival, and integrity of the nigrostriatal pathway and motor performance in the cylinder test. Results: Ipsilateral SNpc cultures yielded 25-fold more cells than contralateral controls. Cultured cells co-expressed astrocytic and microglial markers, thus defining a population of damage-derived reactive glia (DDRG). When co-cultured, DDRG reduced PC12 cell survival, whereas control glial cells showed no neurotoxic effects. In vivo, DDRG transplantation induced a dose-dependent loss of dopaminergic neurons and motor impairments, while vehicle and control glia produced no detectable effects. Conclusions: Our findings suggest that glial cells emerging from a neuroinflammatory/neurodegenerative environment in the SNpc may contribute to dopaminergic neuron loss. Within the context of the experimental PD model used, DDRG appears to represent a glial population with potential pathogenic relevance and may constitute a candidate target for further investigation as a therapeutic strategy in Parkinson’s disease. Full article

Traumatic brain injury (TBI) often leads to long-lasting motor deficits, but the underlying cellular mechanisms still remain poorly understood. In this study, we examined glial and neuronal responses after focal cortical aspiration injury of the right hindlimb sensorimotor cortex in adult male rats. This is a model we have previously shown induces persistent gait asymmetry and postural deficits. Immunohistochemical analysis of activated microglia/macrophages (CD11b, IBA-1), astrocytes (GFAP), and neurons (NeuN) was performed bilaterally in the peri-lesional cortex at 3, 7, 14, 21, and 28 days post-injury (n = 3–6 per time point). The injury induced an early, sharply localized increase in CD11b-positive myeloid cells in the injured hemisphere, suggesting an activation of both resident microglia and infiltrating monocyte-derived cell. This was followed by a more sustained IBA-1-positive microglial activation that gradually extended contralaterally. Astrocytic activation showed a delayed but prolonged profile, rising ipsilaterally within the first week, peaking around two weeks, and becoming bilaterally elevated by four weeks. Sham-operated animals showed only basal glial immunoreactivity without signs of hypertrophy or reactive morphology at any time point. NeuN immunoreactivity remained stable across timepoints, suggesting preservation of neuronal soma labeling without evidence of overt secondary neuronal loss. These findings reveal a staged and spatially distinct glial response to focal cortical injury, with early myeloid activation, prolonged microglial reactivity, and delayed bilateral astrogliosis. Together, these findings are consistent with the possibility that persistent motor deficits after focal TBI arise from both primary tissue loss within the lesion core and peri-lesional glial remodeling, highlighting glial–neuronal interactions as a potential therapeutic target. Full article

Mild traumatic brain injury (mTBI) disrupts hippocampal network function through coordinated alterations in glial reactivity, synaptic integrity, and adult neurogenesis. Effective therapeutic approaches targeting these interconnected processes remain limited. Lipid-derived molecules capable of modulating these mTBI-induced disturbances are emerging as promising neuroprotective candidates. Here, we investigated the effects of N-stearidonylethanolamine (SDEA), an ω-3 ethanolamide, in a mouse model of mTBI. SDEA treatment attenuated astrocytic reactivity, restored Arc expression, and improved dendritic spine density and morphology in the CA1 hippocampal area. In the dentate gyrus, mTBI reduced Ki-67-indexed proliferation while leaving DCX-positive immature neurons unchanged, and SDEA partially rescued proliferative activity. These effects were accompanied by improvements in anxiety-like behavior and working-memory performance. Together, these findings demonstrate that SDEA modulates several key components of the glia-synapse-neurogenesis axis and supports functional recovery of hippocampal circuits following mTBI. These results suggest that ω-3 ethanolamides may represent promising candidates for multi-target therapeutic strategies in mTBI. Full article

The microglia, first identified by Pío del Río-Hortega, are resident macrophages in the CNS that aid in immune monitoring, synaptic remodeling, and tissue repair. Microglial biology’s dual functions in maintaining homeostasis and contributing to neurodegeneration are examined in this review, with a focus on neurodegenerative disease treatment targets. Methods: We reviewed microglial research using single-cell transcriptomics, molecular genetics, and neuroimmunology to analyze heterogeneity and activation states beyond the M1/M2 paradigm. Results: Microglia maintains homeostasis through phagocytosis, trophic factor production, and synaptic pruning. They acquire activated morphologies in pathological conditions, releasing proinflammatory cytokines and reactive oxygen species via NF-κB, MAPK, and NLRP3 signaling. Single-cell investigations show TREM2 and APOE-expressing disease-associated microglia (DAM) in neurodegenerative lesions. Microglial senescence, mitochondrial failure, and chronic inflammation result from Nrf2/Keap1 redox pathway malfunction in ageing. Microglial interactions with astrocytes via IL-1α, TNF-α, and C1q result in neurotoxic or neuroprotective A2 astrocytes, demonstrating linked glial responses. Microglial inflammatory or reparative responses are influenced by epigenetic and metabolic reprogramming, such as regulation of PGC-1α, SIRT1, and glycolytic flux. Microglia are essential to neuroprotection and neurodegeneration. TREM2 agonists, NLRP3 inhibitors, and epigenetic modulators can treat chronic neuroinflammation and restore CNS homeostasis in neurodegenerative illnesses by targeting microglial signaling pathways. Full article

Background/Objectives: Extracellular vesicles (EVs) are key mediators of intercellular communication and are implicated in the neuropathogenesis of HIV-associated brain injury (HABI). However, their direct effects on glial cells, particularly in the context of antiretroviral therapy (ART), remain incompletely understood. Methods: In this study, we investigated how EVs from naïve, Simian Immunodeficiency Virus (SIV)-infected, and SIV-infected ART-treated rhesus macaques impact primary mixed glial cultures. Results: Through multiple, sequential applications mimicking chronic exposure, we found that EVs from SIV-infected animals significantly reduced glial expansion and induced a simplified, reactive astrocyte morphology indicative of neuroinflammatory stress. In contrast, EVs from naïve animals supported glial health. EVs derived from ART-treated animals provided partial protection from SIV-induced effects, yet still suppressed glial proliferation and failed to fully restore normal morphology. Furthermore, cytokine profiling revealed that both SIV and SIV + ART EVs induced a sustained proinflammatory secretory phenotype, characterized by elevated IL-6, IL-8, and IFN-γ. Conclusions: Our findings demonstrate that systemically circulating EVs in SIV infection are potential drivers of glial dysfunction. The persistence of these pathogenic EV effects despite ART suggests a vesicle-mediated mechanism that may contribute to chronic neuroinflammation and cognitive impairment in virally suppressed individuals. Full article

Spastic paraplegia 80 (SPG80), caused by mutations in ubiquitin-associated protein 1 (UBAP1), is a pure form of juvenile-onset hereditary spastic paraplegia (HSP) and leads to progressive motor dysfunction. Despite recent advances in the molecular analyses of HSP, disease-modifying therapy has not been established for HSP including SPG80. In the present study, we evaluated the therapeutic potential of 4-phenylbutyric acid (4-PBA), a chemical chaperone and histone deacetylase inhibitor, in Ubap1 knock-in (KI) mice expressing a disease-associated truncated UBAP1 variant. We found that 4-PBA administration significantly improved the motor performance of KI mice in the rotarod and beam walk tests, with maximal benefits achieved when given during pre- or early-symptomatic stages. Partial efficacy was also observed when treatment began after symptom onset in KI mice. Furthermore, 4-PBA attenuated spinal microglial activation and partially restored microglial morphology, although astrocytic reactivity remained unchanged. These findings support 4-PBA as a candidate therapeutic compound for SPG80 and highlight the potential of proteostasis-targeted interventions in HSPs. Full article

Background: Severe damage to one side of the brain often leads to adverse consequences and can also cause widespread changes throughout the brain, especially in the contralateral area. Studying molecular changes in the contralateral cerebral hemisphere, especially with regard to genetic regulation, can help discover potential treatment strategies to promote recovery after severe brain trauma on one side. Methods: In our study, the right motor cortex was surgically removed to simulate severe unilateral brain injury, and changes in glial cells and synaptic structure in the contralateral cortex were subsequently assessed through immunohistological, morphological, and Western blot analyses. We conducted transcriptomic studies to explore changes in gene expression levels associated with the inflammatory response. Results: Seven days after corticotomy, levels of reactive astrocytes and hypertrophic microglia increased significantly in the experimental group, while synapsin-1 and PSD-95 levels in the contralateral motor cortex increased. These molecular changes are associated with structural changes, including destruction of dendritic structures and the encapsulation of astrocytes by synapses. Genome-wide transcriptome analysis showed a significant increase in gene pathways involved in inflammatory responses, synaptic activity, and nerve fiber regeneration in the contralateral cortex after corticorectomy. Key transcription factors such as NF-κB1, Rela, STAT3 and Jun were identified as potential regulators of these contralateral changes. Quantitative reverse transcription polymerase chain reaction (qRT-PCR) confirmed that the mRNA expression levels of Cacna1c, Tgfb1 and Slc2a1 genes related to STAT3, JUN, and NF-κB regulation significantly increased in the contralateral cortex of the experimental group. Conclusions: After unilateral brain damage occurs, changes in the contralateral cerebral hemisphere are closely related to processes involving inflammation and synaptic function. Full article

The habenula (Hb) of the epithalamus is formed of the medial (MHb) and lateral (LHb) parts. The improper functioning of the Hb may lead to depression and anxiety. The glutamate excitotoxicity is accompanied by astroglia reactivity and leads to the damage of nervous system structures. The aim of the study was to assess the influence of monosodium glutamate (MSG) administrated subcutaneously to rats in doses of 2 g/kg b.w. (I) and 4 g/kg b.w. (II), on astroglia in the MHb and LHb. Based on immunohistochemical reactions, the morphology, number of astrocytes immunoreactive for glial fibrillary acidic protein (GFAP-IR) and S100β protein (S100β-IR), and their surface area, perimeter, number and length of processes, and cytoplasmic-nuclear immunostaining intensity for the studied proteins were assessed. In the MHb of animals receiving MSG, especially at a high dose, hypertrophy and an increase in the number of GFAP-IR and S100β-IR cells were demonstrated. In the LHb, only hypertrophy of processes in S100β-positive glia was observed. The immunostaining intensity increased in GFAP-IR glia and decreased in S100β-IR cells only in animals from group I. The results revealed that astroglia respond to MSG depending on its dose and the Hb part. This different behavior of glia may indicate their different sensitivity and resistance to damaging factors. Full article