Search Results (14,398)

The efficacy of postbiotics varies significantly between different strains and preparation processes. We aimed at evaluating the effect of an innovative postbiotic product (iPB) generated through the sequential fermentation of Lacticaseibacillus rhamnosus GG and Lacticaseibacillus paracasei NPB-01, compared to single-strain postbiotics, on epithelial barrier integrity and innate immunity in human enterocytes using a Caco-2-cell-based experimental model by measuring human enterocyte proliferation and differentiation (lactase expression), tight junction proteins (occludin and zonula occludens 1, ZO-1), and mucus protein Mucin-2 (Muc-2) expression. The modulatory action on the major innate immunity peptide, Human Beta-Defensin 2 (HBD-2), production was also assessed. The iPB exposure resulted in a higher up-regulation of human enterocyte proliferation and differentiation, as suggested by higher lactase expression, and of occludin, ZO-1, and MUC2 expression compared with the single-strain postbiotics, suggesting a beneficial synergistic action in modulating the epithelial gut barrier. Furthermore, iPB induced a higher production of HBD-2, suggesting a synergistic enhancement of innate immune response. Our findings suggested that the sequential fermentation process could act as a biotechnological catalyst, optimizing the gut-barrier-protective properties and the immunomodulatory action of Lacticaseibacillus strains. This study introduces iPB as a high-performance postbiotic candidate for the prevention and management of conditions characterized by alterations in epithelial gut barrier and innate immunity. Full article

Acute kidney injury (AKI), a life-threatening disorder marked by abrupt renal dysfunction, is increasingly recognized as a global healthcare challenge. It not only triggers immediate organ dysfunction but also heightens long-term risks of chronic kidney disease (CKD). The senescence of proximal tubular epithelial cells (PTECs) has a major impact on the occurrence and development of AKI. This review systematically analyzes existing evidence, which suggests that the senescence of PTECs may have a dual effect. Acute cellular senescence typically mitigates uncontrolled replication of damaged cells by inducing cell cycle arrest, thereby limiting the further expansion of tissue damage. In contrast, the pathological retention of chronic senescent cells and the excessive production of the senescence-associated secretory phenotype (SASP) exacerbate the local inflammatory response and the process of fibrosis, accelerating the transformation of AKI into CKD. Despite incomplete elucidation of the spatiotemporal mechanisms governing the transition from acute to chronic cellular senescence, therapeutic interventions can be precisely targeted to specific disease stages based on their characteristic progression dynamics. This review summarizes the intervention strategies applicable at different stages of AKI, including prevention, early induction of senescence, senoreverse, senolysis, and senomorphics. Additionally, we highlight potential therapeutic targets to provide a theoretical basis for optimizing clinical management. Full article

Macrophages are highly plastic cells of the tumor microenvironment, and although classically activated M1 macrophages are generally regarded as anti-tumor effectors, their prolonged cytotoxic activity may also promote tumor adaptation. In this study, we investigated whether sustained exposure of prostate cancer cells to cytotoxic M1-like macrophages results in the selection of tumor cell populations with enhanced malignant properties. Macrophage-resistant derivatives of the human prostate cancer cell lines PC3 and DU145 were generated by repeated co-culture with cytotoxic THP-1-derived macrophages and characterized in vitro and in vivo. Macrophage-selected tumor cells showed increased proliferative activity and enhanced clonogenic survival. In vivo, these cells formed larger xenograft tumors with more aggressive histopathological features. At the same time, their migratory activity was not significantly increased, although they displayed partial epithelial–mesenchymal transition-like changes, including increased vimentin expression without a marked loss of epithelial markers. Transcriptomic profiling revealed coordinated inflammatory and adaptive reprogramming, characterized by the enrichment of cytokine- and immune-response pathways together with the suppression of metabolic and differentiation-associated programs. These changes were accompanied by the selective activation of p38 MAPK signaling, while sensitivity to paclitaxel remained unchanged. Taken together, the results indicate that macrophage cytotoxicity may act as a selective pressure promoting the emergence of inflammation-adapted tumor cell variants with increased malignant potential, supporting re-evaluation of the role of M1-like macrophages in tumor progression. Full article

The retinal pigment epithelium (RPE) is a long-lived, highly polarised epithelial monolayer that performs essential functions in retinal homeostasis, including outer blood–retina barrier maintenance, visual cycle activity, metabolic exchange, phagocytic clearance of photoreceptor outer segments, and regulation of oxidative and immune balance. Because RPE cells persist for decades under conditions of sustained oxidative, metabolic, and phagocytic stress, this tissue provides a valuable model for examining how long-lived post-mitotic cells preserve function over time and how age-related dysfunction emerges when that balance weakens. Although much of the current literature on RPE ageing has been shaped by age-related macular degeneration (AMD), age-dependent change in the RPE should not be understood solely as a preclinical stage of disease. Rather, the ageing RPE offers a broader framework for studying cellular maintenance under chronic physiological load. In this review, we synthesise current evidence on RPE ageing across four interrelated domains: structural remodelling, mitochondrial and metabolic imbalance, proteostatic and lysosomal burden, and chronic inflammatory dysregulation. Across these processes, ageing in the RPE is expressed less as widespread cell loss than as progressive decline in cellular organisation, buffering capacity, and functional precision. Structural irregularity, altered mitochondrial regulation, incomplete degradative clearance, and persistent low-grade inflammatory signalling together reduce the ability of the RPE to maintain long-term homeostasis and increase vulnerability to age-related retinal dysfunction. We further argue that ageing in the RPE is best understood not as abrupt failure of isolated pathways, but as gradual loss of system coherence among interacting homeostatic systems that remain active while operating under increasing constraint. This view helps integrate diverse cellular and molecular findings and highlights the RPE as an informative model for understanding ageing in long-lived post-mitotic tissues. Full article

Weaning impairs intestinal function and growth performance in piglets. This study evaluated a fermented herbal formulation (FHF) composed of five bioactive herbal ingredients—Radix isatidis, Folium isatidis, Radix scutellariae, Fructus forsythiae, and Radix glycyrrhizae—fermented with Enterococcus faecium and Saccharomyces cerevisiae and characterized by flavonoids, phenolic acids, and hydroxylated fatty acids, using the porcine intestinal epithelial cell line (IPEC-J2) and weaned piglets. In vitro, IPEC-J2 cells were pretreated with FHF extract (100–1000 μg/mL) for 3 h prior to lipopolysaccharide (LPS) challenge. In vivo, 72 piglets were weaned at 32 days of age and, after a 3-day post-weaning adaptation period, entered a 35-day feeding trial. The piglets were then randomly assigned to three treatment groups: control (basal diet), A1 (basal diet + 0.4% FHF), and A2 (basal diet + 0.6% FHF during days 1–18, followed by 0.3% FHF during days 19–35). FHF dose-dependently alleviated the LPS-induced decrease in cell viability and suppressed IL-6, IL-8, IL-1β, and TNF-α expression. In piglets, the A2 group showed higher final body weight, average daily gain (ADG), and average daily feed intake (ADFI), lower feed conversion ratio (FCR), and a lower diarrhea rate than the control group. FHF also improved intestinal morphology, reduced serum TNF-α and diamine oxidase (DAO) levels, increased jejunal tight junction protein expression, enriched Limosilactobacillus and Lactobacillus, and elevated acetic and butyric acids. FHF improved intestinal health and growth performance in weaned piglets, with the A2 group showing the best overall efficacy. Full article

Background/Objectives: MSS-CRC comprises a heterogeneous group of tumors generally considered “immune cold” due to limited neoantigen generation and T-cell exclusion or inactivation. Current evidence indicates that the composition of T and B immune cells within the tumor microenvironment represents a prognostically relevant factor, significantly associated with both tumor expression profiles and molecular subtypes. Methods: We conducted an exploratory analysis to identify prognostically relevant immune cell components in this group of tumors and to investigate corresponding differences in RNA-based bulk expression and high-resolution spatial transcriptomic profiles. Results: A total of 254 localized mismatch repair-proficient colorectal cancer cases were evaluated. Our findings revealed PD-L1 expression as a robust independent prognostic biomarker associated with favorable outcomes in this specific population. Bulk RNA expression analysis showed that PD-L1-negative tumors exhibited an expression profile consistent with abundant cancer-associated fibroblast infiltration, increased matrix stiffness, and impaired immune activation—features consistent with tumor progression and poorer clinical outcomes. In contrast, PD-L1-positive tumors displayed stromal programs enriched in immune activation and controlled remodeling, consistent with an immunologically active microenvironment. Spatial transcriptomics added an additional layer of evidence, revealing that epithelial to mesenchymal transition-related programs can dominate stromal niches in PD-L1-negative tumors, particularly within macrophage-enriched stromal regions. Conclusions: Our observations suggest an association between PD-L1 expression on immune cells and immune-activated versus mesenchymal-dominant states, potentially occurring within macrophage-enriched stromal niches. These results provide insight into the biological mechanisms underlying disease progression and highlight tumor-associated macrophages as a potential therapeutic target to overcome immune resistance, particularly in PD-L1-negative MSS-CRC tumors. Full article

Streptococcus canis is an opportunistic pathogen that colonises the mucosal surfaces and skin of its host. Though predominantly a veterinary pathogen affecting cats and dogs, S. canis has also been identified as the causative agent in severe human disease. IdeC is a secreted cysteine protease of S. canis that has a high specificity for IgG, cleaving at the hinge region. We show here that the protein binds back to the surface of the bacteria. Additionally, the protein contains a conserved Arg-Gly-Asp (RGD) motif, the minimal peptide sequence required for integrin binding. Several bacterial proteins containing RGD motifs have been implicated in adhesion and invasion of host cells. This RGD motif along with the ability of IdeC to bind back to the bacterial surface after secretion is the basis for this study into a potential secondary function of IdeC in adhesion and/or invasion. We used protein-coated latex beads to investigate the interaction of IdeC with epithelial and endothelial cells and, further, the extent to which the RGD motif is involved in this interaction by utilising an RGD->RGE recombinant protein. We also report here that the deletion of IdeC in S. canis results in a significant reduction in invasion into epithelial cells. Full article

Epilepsy is associated with impaired reproductive function and testicular pathologies. Intermittent fasting (IF) is a nonpharmacological metabolic intervention with anti-inflammatory and antioxidant effects. This study investigated the protective effects of IF on testicular damage in a genetic absence epilepsy rat model (GAERS), focusing on histomorphology, oxidative stress parameters, and hormonal profiles. Testicular tissues from Wistar control (WC), Wistar + IF (WIF), GAERS control (GC), and GAERS + IF (GIF) groups (total n = 20; 5 rats per group) were evaluated using hematoxylin and eosin and Periodic Acid–Schiff staining. Apoptosis and spermatogenic cell integrity were assessed using caspase-3, P-element-induced wimpy testis (PIWI), and Deleted in Azoospermia-Like (DAZL) immunohistochemistry. Johnsen’s score, seminiferous tubule diameter, and epithelial thickness were quantified. Oxidative stress markers, including catalase, malondialdehyde, glutathione, myeloperoxidase, and superoxide dismutase, were measured using spectrophotometric methods, and serum testosterone, luteinizing hormone (LH), and follicle-stimulating hormone (FSH) levels were determined using ELISA kits. The GC group showed significantly reduced Johnsen scores, tubular diameters, and epithelial thickness, along with disrupted basement membrane integrity and increased caspase-3 immunoreactivity. IF significantly improved histological parameters, restored basement membrane integrity, reduced apoptosis, and increased PIWI and DAZL expression in the GIF group. IF also ameliorated oxidative stress and elevated reproductive hormone levels, indicating positive modulation of the hypothalamic–pituitary–gonadal axis. In conclusion, IF reduces oxidative stress and preserves seminiferous tubules and hormonal function in genetic absence epilepsy, highlighting its potential as a supportive nonpharmacological approach to protect male reproductive health. Full article

Background/Objectives: Developing novel strategies to combat respiratory infections caused by multidrug-resistant “priority pathogens” like the ESKAPEE Pseudomonas aeruginosa and Staphylococcus aureus is an urgent priority. Methods: We investigated two shortened variants of the proline-rich antimicrobial peptide (PrAMP) B7-005, B7-006 (15-mer) and B7-007 (13-mer). Evaluation included MIC assays against laboratory and clinical multidrug-resistant isolates, mechanistic studies of membrane permeabilization, cytotoxicity testing on BEAS-2B bronchial epithelial cells, and proteolytic stability assays in human elastase and sputum. Results: Despite their reduced size, lower positive charge, and decreased proline content, both variants retained full antimicrobial activity against clinical pathogens with consistent MIC values ≤ 25 µM. These variants exhibit membrane permeabilization in P. aeruginosa but may also relay on a hybrid mode of action involving also intracellular targets. Notably, B7-006 and B7-007 displayed low cytotoxicity compared to the lytic peptide BMAP-18. While B7-007 showed greater susceptibility to proteolytic degradation than its parent B7-005, it preserved partial integrity during the initial hours of exposure. Conclusions: Overall, these findings demonstrate that the B7 scaffold tolerates substantial truncation while preserving potency and selectivity, identifying a minimal 13-amino-acid active core. This work provides critical insights into structure–activity relationships and supports the development of compact, mechanistically versatile antimicrobial peptides to address the growing threat of multidrug-resistant respiratory pathogens. Full article

Umbilical cord-derived Platelet-Rich Plasma (ucPRP) promotes corneal regeneration, yet the underlying cellular mechanisms remain incompletely understood. This study evaluated the effects of ucPRP on corneal epithelial cell physiology and wound healing dynamics. In scratch assays, ucPRP treatment significantly accelerated wound closure by enhancing cell migration and proliferation. Confocal microscopy using Fluo-3 demonstrated that ucPRP induces transient increases in intracellular calcium (Ca²⁺), suggesting the activation of upstream signaling events. Furthermore, treated cells exhibited increased membrane permeability to water and hydrogen peroxide (H₂O₂), which correlated with upregulation of Aquaporin-1 (AQP1). Since AQP1 facilitates cell motility, its upregulation links fluid transport mechanisms to the observed regenerative phenotype. These findings suggest that ucPRP drives corneal re-epithelialization by modulating Ca²⁺ signaling and increasing AQP1 expression, supporting its therapeutic utility in ocular surface repair. Full article

Sucralose is one of the most widely used non-nutritive sweeteners and has long been considered metabolically inert and safe within established acceptable daily intake levels. However, emerging evidence suggests that chronic exposure to sucralose may alter gut microbial composition, epithelial barrier function, mucosal inflammation, and immune responses. This review examines current experimental and clinical evidence on the effects of sucralose on the gut–immune axis, with particular attention to its potential implications for colitis and colorectal cancer (CRC). Preclinical studies indicate that sucralose may reduce beneficial short-chain fatty acid-producing taxa, alter microbial metabolic pathways, disrupt epithelial barrier-related molecules, and promote inflammatory and immune changes associated with colitis severity and inflammation-driven tumorigenesis. Experimental evidence also suggests that sucralose may impair CD8⁺ T-cell fitness and reduce responsiveness to immune checkpoint inhibitors through microbiome-dependent mechanisms involving altered arginine and citrulline metabolism. Human studies further indicate that sucralose can modify gut and oral microbiome composition and influence metabolic responses, although these effects appear heterogeneous and context-dependent. Overall, the current literature suggests that sucralose may act as a modifier of microbiome–immune interactions in susceptible settings, but most mechanistic evidence remains preclinical, and human data are still insufficient to establish causality. These findings highlight the need for prospective studies to determine whether sucralose-associated microbial and immune alterations translate into clinically meaningful effects in colitis, CRC, and immunotherapy response. Full article

Trained immunity is a concept that is currently in development and refers to the long-term functional reprogramming of innate immune cells in response to microbial or inflammatory stimuli. This process serves a dual purpose in the gastrointestinal tract, contributing to chronic inflammatory conditions like inflammatory bowel disease and maintaining host defense. The production of pro-inflammatory mediators is augmented by epigenetic and metabolic changes that are induced by the persistent activation of innate immune cells, which is triggered by microbial components and damage-associated signals. Although this increased responsiveness may initially be protective, sustained activation leads to tissue damage, epithelial barrier dysfunction, and chronic inflammation. These mechanisms are significant contributors to colorectal carcinogenesis, particularly in colitis-associated cancer. Through the activation of oncogenic signaling pathways, the establishment of a pro-tumorigenic microenvironment, and an increase in oxidative stress, trained immunity also influences tumor development. Additionally, the systemic reprogramming of hematopoietic progenitor cells has the potential to exacerbate inflammation and facilitate the progression of tumors. The identification of epigenetic and metabolic biomarkers associated with trained immunity can lead to novel diagnostic opportunities. Targeting metabolic and epigenetic pathways, as well as regulating the intestinal microbiota, is a promising therapeutic approach that could enhance the effectiveness of treatments for colorectal cancer while minimizing adverse effects on the immune system. Nevertheless, it is necessary to maintain a delicate equilibrium to suppress pathological inflammation without compromising protective immune responses. In general, trained immunity may represent a potentially relevant mechanistic link between chronic inflammation and colorectal cancer; however, its role remains context-dependent and not yet fully defined. Full article

In vitro cell barrier models have been increasingly integrated into pharmaceutical and academic research pipelines to evaluate drug safety and drug delivery due to a shift towards New Approach Methodologies (NAMs) in research and regulatory safety assessment. Such models require reliable and interpretable functional readouts. Bioimpedance-based monitoring, particularly transepithelial/endothelial electrical resistance (TEER), is a widely adopted readout due to its non-invasive and real-time capabilities. However, substantial variability arises from differences in measurement settings, frequency selection, electrode configuration, impedance measuring techniques, and data analysis strategies. In numerous studies, TEER is approximated from single-frequency impedance magnitude measurements, which do not isolate the resistive component associated with tight junction-mediated paracellular transport but instead reflect the combined response of a coupled electrochemical system. This review clarifies impedance measuring techniques and systematically analyzes impedance-based measurement and analysis strategies for in vitro biological cell barrier integrity. We compare mono-frequency and broadband acquisition approaches, examine the influence of electrode–electrolyte interfaces, electrode geometry, and culture configuration, and evaluate equivalent circuit modeling and phase-resolved electrical impedance spectroscopy (EIS). Based on this comparison, we propose a three-level analytical hierarchy adapted to experimental objectives and instrumentation constraints. We conclude that phase-informed impedance analysis and harmonized reporting are essential to improve measurement reproducibility, inter-platform comparability, and integration of impedance-derived cell barrier assessment within NAMs-oriented research workflows. Full article

Background: Dental caries remains one of the most prevalent oral diseases worldwide, largely driven by the virulence of Streptococcus mutans. Although plant phenolics from green tea and pomegranate are known for their antimicrobial properties, their molecular mechanisms of action against key S. mutans virulence targets remain insufficiently characterized. Aim: This study investigated the antibacterial and anti-virulence properties of Viroelixir, a phenolic-rich formulation derived from green tea (Camellia sinensis) and pomegranate (Punica granatum), against S. mutans, with particular emphasis on predictive molecular docking interactions with critical virulence-associated proteins. Methods: Viroelixir phytochemical composition was characterized by LC–MS using a C18 reverse-phase column and negative electrospray ionization mode. Antibacterial activity was evaluated using growth kinetics, agar plating, and crystal violet assays. Acidogenicity, hemolytic activity, and biofilm formation were assessed using pH modulation, hemolysis assays, SEM, and biofilm biomass quantification. Virulence gene expression was analyzed by RT-qPCR. In silico molecular docking was performed to explore potential interactions between major LC–MS-supported phenolic constituents and S. mutans virulence proteins, including glucosyltransferase B (GtfB), LuxS, and SpaP. Biocompatibility was evaluated in human gingival epithelial cells. Results: The LC-MS analysis revealed a complex mixture of phenolic compounds consistent with catechins and ellagitannins. Compound identification was considered tentative and based on mass spectral range and chromatographic behavior. Viroelixir significantly inhibited S. mutans growth, acid production, hemolytic activity, and biofilm formation in a concentration-dependent manner. Key virulence genes were markedly downregulated. Docking analyses suggested stable binding of selected phenolics—particularly punicalagin, catechin, and epigallocatechin—within the active sites of GtfB, LuxS, and SpaP. Importantly, Viroelixir showed no cytotoxic effects on gingival epithelial cells. Conclusions: Viroelixir exerts potent antibacterial and anti-virulence effects against S. mutans through a multi-target mechanism combining transcriptional suppression and predictive molecular inhibition of virulence proteins, supporting its potential as a safe, natural therapeutic for caries prevention. Full article

Antioxidant peptides show significant activity and can be developed into functional foods for treating chronic diseases. Cigarette smoke components can cause damage or even apoptosis of lung cells, eventually leading to chronic lung diseases. Therefore, this study aimed to investigate the protective effects and mechanisms of Skipjack tuna peptides against in vitro cigarette smoke extract (CSE)-induced chronic obstructive pulmonary disease (COPD). The results demonstrated that tuna peptides DVGRG (S1), PHPR (S5), GRVPR (S6), and SVTEV (S7) significantly enhanced the activities of SOD, CAT, and GSH-Px by upregulating the mRNA transcription levels of Keap1 and Nrf2, consequently reducing ROS and MDA levels in CSE-induced COPD model of MLE-12 cells. Molecular docking analysis revealed that S1, S6, and S7 competitively inhibited the Keap1-Nrf2 interaction by binding to the Kelch domain of Keap1, whereas S5 operated through a non-competitive mechanism. These peptides also downregulated p65 mRNA expression and upregulated IκBα mRNA expression, leading to a significant reduction in inflammatory cytokines of IL-1β, IL-6, and TNF-α, thereby alleviating inflammatory responses. Furthermore, these peptides significantly inhibited CSE-induced apoptosis by restoring mitochondrial membrane potential and upregulating the Bcl-2/Bax ratio. Additionally, S1, S5, S6, and S7 promoted MLE-12 cell migration in a concentration-dependent manner, suggesting a role in lung epithelial repair and regeneration. In conclusion, tuna peptides S1, S5, S6, and S7 exert antioxidant, anti-inflammatory, anti-apoptotic, and cell migration-promoting effects through the regulation of the Keap1/Nrf2 and NF-κB signaling pathways, as well as Bcl-2/Bax apoptotic balance, providing a promising strategy for mitigating CSE-induced lung injury. Full article