Search Results (21,419)

Background/Objectives: Cell-free DNA (cfDNA) is released into the circulation during inflammation-driven cellular injury and regulated cell death. Elevated cfDNA concentrations have been reported in several clinical settings, including chronic kidney disease, hemodialysis, and peritoneal dialysis (PD). We previously demonstrated that PD-related peritonitis induces an increase in circulating cfDNA; however, the mechanisms underlying cfDNA generation remained unclear. This study aimed (i) to confirm peritoneal cfDNA variation following peritonitis in PD patients, and (ii) to elucidate the apoptotic pathways responsible for cfDNA release. Methods: Fifty-four PD patients were enrolled and stratified into the following groups: Group A—no history of peritonitis (n = 25); Group B—remote peritonitis > 3 months prior (n = 21); Group C—recent peritonitis < 3 months prior (n = 8). cfDNA was quantified by qPCR. Apoptosis was assessed qualitatively by DNA laddering and quantitatively using ELISA assays for Caspase-3, Caspase-8 and Caspase-9. Results: cfDNA levels were significantly higher in patients with recent peritonitis compared to both other groups (p < 0.01). DNA laddering showed enhanced nucleosomal fragmentation, consistent with apoptosis. Caspase-3 concentrations were markedly increased in recent peritonitis (<3 months) and significantly correlated with cfDNA levels (ρ = 0.511, p < 0.01). Both Caspase-8 and Caspase-9 correlated with Caspase-3 (ρ = 0.57 and ρ = 0.47, respectively), indicating engagement of both extrinsic and intrinsic apoptotic pathways. Conclusions: In conclusion, peritoneal cfDNA in PD patients with peritonitis originates primarily from apoptosis and reflects dual-pathway caspase activation. cfDNA and Caspase-3 progressively decline with longer time elapsed from peritonitis, supporting their potential use as biomarkers for inflammatory activity and membrane recovery. Full article

Metal ion-based chemo-immunotherapy is often limited by rigid intracellular metal homeostasis, insufficient reactive oxygen species (ROS) accumulation, and an immunosuppressive tumor microenvironment (TME). To overcome these limitations, we engineered an ATP-responsive, core–shell bimetallic nanoreactor (Cu/ZIF@PDA, termed CZP) featuring a precisely controlled ~25 nm biomimetic polydopamine (PDA) coating. Triggered by elevated tumoral ATP levels, CZP undergoes coordination-induced disassembly and promotes oxidative stress amplification. Specifically, the PDA shell acts as a superoxide dismutase (SOD) mimetic to continuously supply H₂O₂, fueling Cu²⁺-mediated Fenton-like reactions to unleash highly toxic hydroxyl radicals (•OH) while aggressively depleting the intracellular glutathione (GSH) pool. This irreversible oxidative damage, coupled with Zn²⁺-induced mitochondrial dysfunction, triggers profound mitochondrial DNA (mtDNA) leakage. Crucially, this cytosolic DNA robustly activates the cGAS-STING signaling axis, driving a massive surge in immunogenic cell death (ICD) and significantly promoting dendritic cell (DC) maturation. Furthermore, CZP markedly inhibited primary tumor growth in vivo and showed protection in a tumor re-challenge model, accompanied by enhanced dendritic cell maturation. These findings support the potential of this ATP-responsive bimetallic nanoplatform to promote antitumor immune activation. Full article

Background: The immunologically cold nature and immunosuppressive tumor microenvironment (TME) of intrahepatic cholangiocarcinoma (ICC) contribute to its poor prognosis. This study aims to identify novel biomarkers related to prognosis and TME in ICC. Methods: We first identified the high expression of m6A reader insulin-like growth factor 2 mRNA binding protein 2 (IGF2BP2) in ICC through bioinformatics screening. Subsequently, a retrospective study was conducted on 224 ICC patients who had undergone radical resection. The expression levels of IGF2BP2 and programmed death ligand 1 (PD-L1) were detected in a tissue microarray (TMA) using immunohistochemistry (IHC). The co-localization of IGF2BP2, PD-L1, programmed cell death protein 1 (PD-1), and CD8⁺T cells was evaluated by multiple immunofluorescence techniques. Results: IHC confirmed a significant upregulation of IGF2BP2 in tumor tissues compared with normal bile duct epithelia (p < 0.05). IGF2BP2 expression was positively correlated with PD-L1 expression (TPS R = 0.215, p = 0.016; CPS R = 0.295, p = 0.008). High IGF2BP2 expression was associated with increased PD-L1/PD-1 positivity and reduced CD8⁺T cell infiltration. Kaplan–Meier analysis revealed significantly worse 3-year overall survival (OS: 20.56% vs. 29.91%, p = 0.0291) and recurrence-free survival (RFS: 9.72% vs. 18.56%, p = 0.0372) in the IGF2BP2-high group. Multivariate analysis identified IGF2BP2 as an independent risk factor for both OS (HR = 1.683, p = 0.044) and RFS (HR = 1.946, p = 0.042). Conclusions: IGF2BP2, as a potential biomarker and independent prognostic factor for ICC, is associated with increased PD-L1 expression. Full article

Neurodegenerative disorders (NDs), such as Alzheimer’s and Parkinson’s diseases (AD and PD), despite having different main neuropathological hallmarks, share several interconnected aetiologic mechanisms and lack effective disease-modifying treatments. The multifactorial nature of these diseases has encouraged the development of new drugs such as multi-target-directed ligands (MTDLs). In this work, an anti-AD drug (rivastigmine, RIV) was fused and conjugated with a series of antioxidant scaffolds to obtain a small library of RIV–antiox hybrids. In addition to inhibitory activity towards both cholinesterases, these hybrids exhibited radical scavenging activity, inhibition of Aβ aggregation, and neuroprotection against cell death induced in AD models. The relevant anti-AD properties already found for these hybrids challenged us to also assess their capacity to modulate and interfere with ROS-associated harmful dysfunctions, namely in the dysregulation of biometal ions (Fe³⁺, Cu²⁺, and Zn²⁺) and upregulation of monoamine oxidases (MAOs). In particular, the capacity of the hybrids for metal chelation and inhibition of Cu-induced Aβ aggregation and MAO isoforms was evaluated, as well as their neuroprotection capacity in cell models of PD. Overall, some of these RIV hybrids appear as lead compounds for the development of novel multifunctional agents against NDs. Full article

Tumor oxygenation is a key determinant of cancer biology and treatment response, correlating with angiogenesis, recurrence, and malignant progression. Hypoxia is a defining feature of glioblastoma (GBM) and adult diffuse gliomas, generating low-oxygen niches that promote invasion, stem-like states, immune suppression, and resistance to radiotherapy and temozolomide, contributing to poor outcomes. Measuring tissue partial pressure of oxygen (pO₂) and mapping its spatial heterogeneity can, therefore, inform mechanistic understanding and therapeutic development, including hypoxia-activated prodrugs, hypoxia-responsive gene therapy, and optimized radiotherapy planning. Although direct pO₂ assessment is challenging, invasive probes and multimodal imaging can characterize regional hypoxia pre-operatively, support patient stratification, monitor treatment effects, and improve outcome prediction. This review summarizes oxygen dynamics in GBM; analyzes causes of hypoxia (rapid growth outpacing supply, diffusion-limited hypoxia, and abnormal/chaotic vasculature); compares methods to quantify oxygenation from direct measurements to noninvasive imaging surrogates; and evaluates preclinical and clinical strategies that target hypoxia to enhance standard therapy, including barriers to translation. We further integrate oxygenation with cell signaling and redox biology: oxygen gradients are transduced via hypoxia-inducible factor programs and redox-sensitive pathways (NRF2/KEAP1, NOX-derived ROS, nitric oxide/S-nitrosylation, and sulfur metabolic routes), shaping mesenchymal-like transitions and cell-death programs such as ferroptosis. Framing oxygenation as both a microenvironmental and redox-signaling variable positions oxygen imaging as an entry point to biomarker-guided therapies that exploit oxidative vulnerabilities. Full article

Alphaviruses are mosquito-borne viruses that can infect the central nervous system (CNS) and cause encephalomyelitis, which is a rare but dangerous complication from infection. In mice, this can be studied in a model of infection with Sindbis virus (SINV), which infects neurons and causes neurological disease. Due to the non-renewable nature of neurons, the immune response in the CNS is specialized to prevent neuronal damage or death, even if they are infected. Therefore, insights into the nuances of antiviral immunity in the CNS provide a better understanding of disease pathogenesis and mechanisms of recovery. Type I interferons (IFNs) are critically important for survival; they are an innate antiviral defense mechanism that consists mainly of IFNα and IFNβ. Although both use the same receptor, type-specific differences between IFNα and IFNβ have been described in other contexts. To this end, Ifnb^−/− mice were used to elucidate the role of IFNβ in recovery from alphavirus encephalomyelitis. IFNβ-deficient mice have intact IFNα expression and downstream signaling, but symptomatic disease occurs earlier and is more severe. This is accompanied by increased virus replication in the early stages of infection. Microgliosis is reduced in Ifnb^−/− mice compared to wildtype, but inflammatory cytokine/chemokine levels are higher and associated with alterations in monocyte and NK cell recruitment into the CNS. Ifnb^−/− mice have no deficiencies in the expression of factors known to be required for viral clearance. Therefore, IFNβ modulates the early stages of the immune response and facilitates restriction of virus replication, contributing to delayed disease onset. Full article

This study investigates the mechanism of cell death associated with discharge plasma treatment from the perspective of electrical energy injection, using equivalent circuit network analysis to represent cells, buffer solutions, and well plates as electrical components. Our analysis demonstrated that the observed cell death cannot be adequately explained by a One-Step Model, which assumes that cell death occurs when the total injected electrical energy simply reaches a specific threshold. Accordingly, we proposed a Two-Step Model that explicitly incorporates biological tolerance to external stimuli. In this model, a stimulus accumulates only when the instantaneous power exceeds a primary threshold, and cell death is induced only when this accumulated stimulus surpasses a secondary threshold of energy. The proposed Two-Step Model successfully reproduced the experimental cell death data. These findings suggest that plasma-induced cell death is not a simple physical destruction process governed solely by cumulative energy, but instead reflects a biologically regulated response characterized by a specific power-dependent tolerance. Consequently, this Two-Step Model could provide a theoretical foundation for future optimization of delivery conditions for macromolecules such as messenger RNA (mRNA). Full article

Neonatal hypoxic ischemic encephalopathy (HIE) is a common birth complication that can cause death or lifelong disabling conditions like cerebral palsy, epilepsy, and autism. It is well established that maternal infection and inflammation are significant risk factors for HIE but reasons for this increase in neurological risk to the offspring remain unknown. Inflammation or infection are associated with epigenetic changes and may contribute to the increased risk of neurodevelopmental disability in exposed offspring. Here, we analyzed and compared DNA methylation patterns in brain monocytes isolated from control, maternal immune activation (MIA), and an inflammation sensitized HIE (IS-HIE) CF-1 mouse model at postnatal day 7. We found that maternal inflammation induced significant methylation differences in neonates relative to control samples in both MIA and IS-HIE samples with no significant differences identified between the MIA and IS-HIE groups. MIA samples showed hypermethylation at loci involving craniofacial development and transcription factors important for regulating neurodevelopment and immune function. MIA samples also demonstrated significant hypermethylation at multiple mitochondrial genome CpGs. These findings suggest that maternal inflammation induces epigenetic alterations in fetal brain immune cells that are detectable in neonates. These changes may contribute to heightened neurodevelopmental risk in offspring following hypoxic injury, highlighting potential molecular pathways for future therapeutic targeting. Full article

Candida albicans is a ubiquitous commensal fungus that may be lethal once it gains access to the bloodstream, following a breach in protective barriers such as skin or gut lining. Intravenous injection of C. albicans (4.5 × 10⁴ yeasts/gm of mouse) leads reproducibly to systemic infection with a median survival of about 75 h. We studied the effects of two human innate immune effectors on the course of systemic infections. The soluble human pentraxin serum amyloid P component (hSAP) retards death in murine disseminated candidiasis. In contrast, another soluble pentraxin, human C-reactive protein (hCRP), hastens death. To examine the pathological basis for these differences, necropsies were performed, and the right kidney was removed for study. Candidiasis caused abundant collagen deposition (the precursor to fibrosis) and loss of contrast between the kidney medulla and cortex. Daily administration of subcutaneous hSAP following the intravenous injection of C. albicans preserved the discrete histological difference between cortex and medulla and lessened host collagen deposition. Yeasts and hyphae within abscesses were decorated with hSAP. Contrastingly, kidneys from animals administered C. albicans and hCRP showed extensive collagen deposition and loss of the boundary between the cortex and the medulla of the kidney. hCRP did not bind to fungi but bound to damaged tissue surrounding abscesses, leading to a more destructive infection with loss of tissue. Staining cells with antibodies to CD45 (to detect T-lymphocytes, myelocytes, monocytes, and macrophages) and antibodies to Ly-6G (neutrophils, and granulocytes) showed that hSAP retarded infiltration of inflammatory cells into diseased areas. The results are consistent with the hypothesis that early administration of hSAP represses the migration of inflammatory cells, dampens the production of collagen by fibroblasts, and dampens the overall immune response of the host to infection. In doing so, hSAP prolonged life, whereas hCRP facilitated the infectious process and hastened death. Full article

Vascular diseases impose a heavy global burden, yet existing therapies have limitations, necessitating novel drug targets. Ferroptosis, an iron-dependent, lipid peroxidation-driven form of cell death, acts not only as an initiator of metabolic collapse but also as a sterile inflammatory trigger by releasing damage-associated molecular patterns (DAMPs) and activating pro-inflammatory pathways. In this paper, we propose the “ferroptosis–inflammation circuit” as a self-amplifying loop where ferroptosis fuels inflammation and the inflammatory microenvironment reciprocally promotes ferroptosis via cell type-specific mechanisms. Although ferroptosis in cardiovascular diseases has been reviewed, its immunopathological role in specific vascular diseases and how macrophages, neutrophils, T cells, and vascular cells collaboratively drive pathology through this circuit remains underexplored. The unique perspective of this review is a systematic focus on the dynamic interplay between ferroptosis and immune responses within the vascular wall, moving beyond static metabolic descriptions. We synthesize evidence linking ferroptosis to atherosclerosis, pulmonary hypertension, stroke, aneurysms, and aortic dissection, emphasizing its immunological dimension across cell types. By defining the ferroptosis–inflammation circuit and its cell type-specific patterns, we reposition ferroptosis as a core pathological hub that couples metabolic dysregulation, immune activation, and vascular remodeling. Understanding this circuit may open novel therapeutic avenues for targeting the ferroptosis–immune interface. Full article

Background/Objectives: Lung cancer (LC) remains the leading cause of cancer-related death worldwide, despite advances in systemic and targeted therapies. A mechanism of survival of tumor cells is metabolic reprogramming, characterized by increased glucose uptake, aerobic glycolysis, and alterations in mitochondrial function. These adaptations seem to support tumor growth, immune evasion, and therapeutic resistance. In parallel, supportive care and specifically nutritional interventions have become essential components of modern oncology. The interplay between metabolic reprogramming and targeted nutritional strategies represents a promising area of investigation that bridges tumor biology with supportive care, aiming to enhance both therapeutic efficacy and patient quality of life. Methods: This narrative review explores the biological and pathophysiological rationale for the ketogenic diet (KD) as a possible complementary intervention in LC management and summarizes the published preclinical and clinical data supporting this rationale. Results: We discuss key aspects of tumor metabolism, including the Warburg effect, glucose dependency, oxidative stress regulation, fatty acid metabolism, lactate cycling and tumor microenvironment interactions, with particular emphasis on how carbohydrate restriction and ketosis may exacerbate mitochondrial dysfunction in cancer cells and modulate inflammatory pathways. Furthermore, we summarize available preclinical and clinical evidence evaluating the KD in oncology and, more specifically, in LC, focusing on feasibility, safety, metabolic effects, and potential synergy with chemotherapy, radiotherapy, and immunotherapy. Conclusions: While preclinical models suggest enhanced treatment efficacy, clinical data remain limited and heterogeneous, with patient adherence representing a major challenge. Further well-designed longitudinal studies are required to clarify the therapeutic role of the ketogenic diet in lung cancer. Full article

Quercetin, a naturally occurring flavonoid, exhibits antiproliferative and pro-apoptotic effects across various cancer models. Topotecan, a topoisomerase I inhibitor, is used in the treatment of retinoblastoma; however, its clinical utility is limited by dose-dependent toxicity. This study aimed to investigate whether quercetin is associated with enhanced topotecan-induced cytotoxicity in retinoblastoma and to explore the underlying mechanisms under both two-dimensional (2D) and three-dimensional (3D) conditions. Cell viability was assessed using the MTT assay, and drug interactions were evaluated using the combination index (CI) based on the Chou–Talalay method. Apoptosis was analyzed by Annexin V-FITC/PI staining and flow cytometry. Reactive oxygen species (ROS) levels and mitochondrial membrane potential were evaluated using fluorometric methods, and N-acetyl-L-cysteine (NAC) was used for functional modulation of oxidative stress. Three-dimensional tumor spheroid models were used to assess treatment effects under conditions that partially recapitulate tumor architecture. Gene expression levels of apoptosis-related markers and PI3K/Akt/mTOR pathway components were analyzed by quantitative real-time polymerase chain reaction (qRT-PCR). The combination of quercetin and topotecan was associated with synergistic cytotoxic effects in Y79 cells (CI < 1), accompanied by increased ROS levels, mitochondrial membrane depolarization, and elevated apoptotic cell death. NAC co-treatment partially attenuated ROS levels and restored cell viability. In 3D spheroid models, combination treatment induced structural disruption, reduced viability, and increased cell death, effects that were partially reversed by NAC. Gene expression analysis revealed upregulation of pro-apoptotic genes and downregulation of survival-related genes, along with increased PTEN expression. Quercetin is associated with enhanced topotecan-induced cytotoxicity in retinoblastoma cells under both 2D and 3D conditions. These effects were associated with ROS-associated cellular stress, mitochondrial dysfunction, and modulation of apoptotic and survival-related pathways. The partial rescue by NAC supports a contributory, but not exclusive, role of oxidative stress. These findings should be interpreted within a preclinical context and suggest that quercetin may represent a potential adjunct strategy warranting further validation in translational and in vivo models. Full article

Air pollution remains a critical environmental and public health threat, particularly in highly populated urban areas such as the Lisbon Metropolitan Area (LMA). This study provides a refined and detailed assessment of the spatial distribution of air pollution and associated attributable mortality across the LMA. High-resolution (1 km²) annual mean concentrations of key pollutants (PM_2.5, PM₁₀ and NO₂) for 2022 and 2023 were estimated by integrating outputs from the URBAIR dispersion model with ground-based monitoring observations using advanced geostatistical data-fusion techniques. Air pollutant concentrations were combined with gridded population data and age-stratified baseline mortality rates within a Geographic Information System framework to quantify spatial variations in health impacts. Using the World Health Organization AirQ+ framework and established concentration–response functions, we estimated a total of 3195 air-pollution-attributable deaths across the Lisbon Metropolitan Area (LMA) in 2022, increasing to 4010 deaths in 2023. Fine particulate matter (PM_2.5) was identified as the dominant contributor, accounting for more than 40% of the total health burden. At a high spatial resolution (1 km² grid), estimated mortality exhibited substantial variability, ranging from 0 to 29 deaths per cell in 2022 and from 0 to 36 deaths per cell in 2023. These results highlight the importance of fine-scale spatial analysis, revealing intra-urban disparities that are not captured by aggregated estimates of total attributable mortality. The proposed methodological framework, integrating dispersion modelling, data fusion, and spatially explicit health impact assessment at fine spatial scales, provides a robust and transferable approach to support evidence-based air quality management and urban health policy development in European metropolitan contexts. This integrated approach enhances comparability, improves exposure assessment accuracy, and strengthens the scientific basis for designing targeted mitigation strategies that could prevent hundreds of premature deaths annually while addressing documented spatial inequalities in pollution exposure. Full article

Nuclear transport is a vital system that mediates movement of essential biomolecules between the nucleus and cytoplasm. It is tightly regulated by the Importin (IMP) superfamily to maintain separation of cellular compartments. Cellular stress in various forms, particularly oxidative, can suspend nuclear transport and lead to cell death. Prolonged oxidative stress manifests in myriad conditions, including cancer, viral infection and metabolic disease. An IMP protein, Importin-13 (IMP13), retains function under stress, while all other IMP family members tested to date do not. Phylogenetic and structural analysis revealed Transportin-3 (TNPO3) as the closest homologue of IMP13, suggesting it may also retain its function under stress. Subcellular localisation studies indicated that TNPO3 maintained its typical subcellular localisation, even in the presence of stress, unlike most IMP family members. Also, fluorescence recovery after photobleaching (FRAP) demonstrated that TNPO3 shuttling is unaffected under stress. Co-immunoprecipitation studies examining cargo binding revealed the capacity of TNPO3 to bind its cargo in the presence of stress. This demonstrated for the first time that TNPO3 retains functionality under stress conditions, in contrast to other IMPs, but similar to IMP13. Furthermore, both IMP13 and TNPO3 appear to protect against the potentially critical mislocalisation of Ran, a key molecule involved in the maintenance of the nuclear transport system. Full article

With the continuous expansion of Pleurotus ostreatus cultivation, substantial quantities of post-harvest spent mushroom substrate (SMS) are generated. Improper disposal of this organic waste poses potential threats to soil health, including contamination and ecological imbalance. Consequently, a rigorous safety assessment is indispensable to support the sustainable and agronomically viable utilization of SMS as a soil amendment. In this study, P. ostreatus SMS was subjected to sterilized and non-sterilized treatments, and a controlled co-culture system integrating P. ostreatus mycelium with wheat was established. This system facilitated a comprehensive evaluation of residual mycelium impacts on wheat growth and development at phenotypic, cytological, and non-targeted metabolomics (LC-MS) levels. Results demonstrated that direct field application of non-sterilized SMS severely compromised wheat performance, inducing root necrosis and significantly reducing grain set. Comparative experiments confirmed that non-sterilized SMS—not its sterilized counterpart—exerted pronounced phytotoxic effects, markedly inhibiting seedling growth and triggering wilting symptoms. To elucidate the temporal dynamics of mycelial interaction, wheat seedlings were inoculated with viable P. ostreatus mycelium and co-cultured for seven days. Under these conditions, the mean root length of the control group (10.82 cm) was approximately threefold that of the treatment group. Histopathological analysis revealed a progressive infection pattern initiating at the root apex and extending basipetally; prolonged exposure ultimately caused complete root system collapse. Scanning electron microscopy further showed extensive mycelial colonization on infected root surfaces, accompanied by characteristic cellular damage—including severe cell wall wrinkling and widespread cell death. LC-MS profiling identified 1867 annotated compounds. Comparative analysis revealed significant dysregulation of secondary metabolism, with 495 metabolites upregulated and 419 metabolites downregulated in the treatment group. Collectively, these findings provide robust evidence that unprocessed P. ostreatus SMS poses tangible agronomic risks upon direct soil application. This study establishes a critical scientific foundation for developing safe, evidence-based protocols for the valorization and integrated management of SMS. Full article