Search Results (889)

Background/Objectives: Cigarette smoke (CS) drives pathogenesis across the spectrum of chronic respiratory disorders, exerting its detrimental effects primarily through oxidative stress and programmed cell death. Scutellarein (Scu), a botanical-origin flavonoid enriched in respiratory therapeutics-oriented Chinese medicinal herbs, demonstrates established anti-inflammatory applications. This study systematically evaluated the protective roles of Scu against CS-induced lung injury and explored the underlying mechanisms. Methods: Subacute CS-exposed mice were used to evaluate the therapeutic effects of Scu on lung injury. Immunofluorescence and quantitative PCR were used to examine the expression levels of junctional proteins and proinflammatory mediators. Apoptotic cell death was quantified using Annexin V-FITC/7-AAD staining. Transepithelial electrical resistance and dextran permeability assay were used to access the barrier integrity in alveolar epithelial MLE-12 cells. Western blotting was used to detect the changes in the signal pathway. Results: In CS-exposed mice, Scu administration dose-dependently reduced histopathological scores, pulmonary edema, changes in the alveolar structure, and inflammatory cell infiltration. In MLE-12 cells, Scu significantly suppressed cigarette smoke condensate (CSC)-induced inflammatory mediators, oxidative stress, caspase-3 activation, and apoptosis and preserved CSC-suppressed tight junction protein expression and barrier disruption. Scu also rescued CSC-altered expression levels of Hrk, Ecscr, and Myo5b and mitigated the CSC-suppressed PI3K/AKT/mTOR pathway. Conclusions: Scu alleviates CS-induced subacute lung injury through its antioxidant, anti-apoptotic effects to maintain epithelial barrier integrity likely via the mitigation of the CSC-suppressed PI3K/AKT/mTOR pathway. Full article

The rising global incidence of Candida parapsilosis infections is increasingly complicated by antifungal resistance, resulting in frequent therapeutic failure. This study investigated the potential of the natural compound catechin to enhance the efficacy of fluconazole through synergistic interaction. We evaluated the susceptibility of C. parapsilosis clinical isolates and a reference strain to combinations of catechin and fluconazole using standardized microbiological assays and molecular techniques. In vivo efficacy was assessed using the Galleria mellonella infection model. Mechanistic studies included the measurement of intracellular reactive oxygen species (ROS) production and plasma membrane permeability. Catechin alone caused growth retardation in all strains. However, the combination of catechin and fluconazole resulted in complete growth inhibition of the reference strain and significant growth reduction in azole-resistant clinical isolates. While the combination slightly increased intracellular ROS production, no significant changes in plasma membrane permeability or membrane potential were observed. Notably, catechin induced the expression of the resistance-associated genes CpTAC1 and CpCDR1B in resistant isolates. In vivo experiments demonstrated that catechin significantly reduced mortality in G. mellonella larvae infected with C. parapsilosis. These findings suggest that catechin is a promising candidate for developing synergistic antifungal therapies against resistant Candida species. Full article

Inflammatory bowel disease (IBD) involves chronic inflammation and disruption of the intestinal barrier, often accompanied by alterations in gut microbiota composition. This study examined the protective potential of a prebiotic mixture extract (PME) prepared from Vigna radiata (mung bean), Vigna angularis (red bean), and Foeniculum vulgare (fennel) using the HT-29 cell and colitis animal model. PME exhibited concentration-dependent antioxidant activity, with greater radical-scavenging capacity in the ABTS assay than in the DPPH assay. In LPS-stimulated HT-29 epithelial cells, PME reduced the mRNA expression of inflammation-associated genes (TNF-α, IL-1β, NF-κB) and upregulated tight junction markers (CLDN1 and OCLN), demonstrating its anti-inflammatory and supportive effects on the intestinal barrier. Vitexin, a C-glycosylated flavonoid, was detected in PME and is expected to mediate these protective effects. In a DSS-induced colitis mouse model, PME administration alleviated disease severity by increasing colon length, reducing serum levels of inflammatory cytokines and COX-2/PGE2, and restoring intestinal permeability. Furthermore, PME modulated the gut microbiota by enhancing beneficial bacteria such as Bifidobacterium and Faecalibaculum while suppressing inflammation-associated taxa, including Escherichia, Bacteroides, and Mucispirillum. These improvements collectively suggest that PME reinforces epithelial barrier integrity and promotes intestinal homeostasis through both anti-inflammatory and microbiota-regulating actions. Full article

White-nose syndrome (WNS) is an infectious disease of bats caused by the psychrophilic fungus Pseudogymnoascus destructans. Phenazine-1-carboxylic acid (PCA) is a microbial secondary metabolite with broad-spectrum antifungal activity. Previous studies show that PCA suppresses the growth of P. destructans at low concentrations, yet its mechanism remains unclear. Here, we evaluated the in vitro antifungal activity of PCA. We then investigated its potential mechanism using physiological and biochemical assays, as well as integrated transcriptomic and metabolomic analyses. PCA showed effective antifungal activity against P. destructans (EC₅₀ = 32.9 μg/mL). Physiological and biochemical assays indicated that PCA perturbed cell wall organization and increased membrane permeability, leading to leakage of intracellular contents. It also induced oxidative stress, DNA damage, and apoptosis. Multi-omics integration revealed that PCA markedly perturbed cell wall and membrane metabolism, virulence factor expression, and energy metabolism. It provoked oxidative stress while downregulating genes involved in the cell cycle, DNA replication, and repair. Together, these findings delineate the inhibitory effects of PCA on P. destructans in vitro, provide initial mechanistic insights into its antifungal action, and suggest that PCA merits further evaluation as a possible component of environmentally compatible strategies for WNS management. Full article

Background/Objectives: The pathogenesis of ulcerative colitis (UC) is complex, and there is an urgent need for effective therapeutic agents with low side effects. Recent studies highlight the critical roles of abnormal bile acid (BA) metabolism and gut microbiota dysbiosis in UC progression. However, there is a significant knowledge gap about the relation between BA and gut microbiota. The BA derivative T3K exerts good anti-UC effect, and its mechanism is still unknown. In this study, we investigate how its anti-UC mechanism is involved in the modulation of the gut microbiota-BA axis and BA metabolism. Methods: Gene expression microarray GSE92415 of UC from the Gene Expression Omnibus was used to analyze BA metabolism. DSS-induced colitis mouse model, Caco-2 and IEC6 cells were used to confirm the anti-UC of T3K using intestinal permeability assay with FITC, Western-blot, immunohistochemical staining, immunofluorescenc and so on in vitro and in vivo. The changes in bile acid and microbiota were measured by 16S rRNA sequencing and bile acid analysis combined with pseudo-germ-free (PGF) models and fecal microbiota transplantation (FMT). Results: T3K demonstrated strong therapeutic effects, including reduced weight loss, lower disease activity index (DAI), and increased colon length. T3K also enhanced the expression of Occludin and Mucin2, and restored gut barrier integrity. Furthermore, T3K improved intestinal dysbiosis and abnormal BA metabolism in colitis mice. Through PGF models and FMT, we confirmed that T3K modulates BA metabolism via the gut microbiota. T3K specifically promotes the growth of beneficial bacteria, such as Akkermansia muciniphila, increases levels of hydrophilic BAs like muricholic acid (MCA), lithocholic acid (LCA) and its derivatives isoLCA and then repairs damaged intestinal mucosa. Conclusions: Bile acid derivative T3K, as a potential anti-UC candidate, effectively restores gut barrier integrity and then ameliorates colitis by improving gut microbiota composition and regulating BA metabolism, including increasing hydrophilic BAs. Full article

Onion (Allium cepa L.) peels represent a major agro-industrial by-product and are a rich source of polyphenols, with recognized antioxidant properties. This study compared the polyphenolic profile of two onion cultivars peels: red “Rossa di Tropea” and yellow “Recas”. Their digestive stability, intestinal bioavailability, and antioxidant activity were evaluated. Hydroalcoholic extracts were characterized by HPLC-DAD, subjected to a static gastrointestinal digestion model, and assessed for transport across differentiated Caco-2 monolayers. Antioxidant properties were determined using DPPH, FRAP, Cellular Antioxidant Activity (CAA), and intracellular glutathione (GSH) assays. Red peels contained a higher total polyphenol content (28.44 mg/g DW) than yellow peels (15.61 mg/g DW), including anthocyanins uniquely present in the red cultivar. Digestive stability varied markedly between cultivars, with yellow peels showing greater intestinal recovery (72.7%) than red peels (49.1%). Glycosylated flavonols were more stable and exhibited moderate intestinal transport (Papp = 1.1–9.9 × 10⁻⁶ cm·s⁻¹), whereas quercetin aglycone showed low permeability. Red peel extracts demonstrated stronger chemical antioxidant activity, while yellow peels were more effective in cell-based assays, displaying higher CAA values and inducing a pronounced increase in intracellular GSH. Overall, onion peel extracts exhibit promising antioxidant and biological properties. However, their limited bioavailability highlights the need for formulation strategies to enhance gastrointestinal stability and intestinal uptake, supporting their potential use as sustainable functional ingredients. Full article

Numerous modern scientific studies have demonstrated that animal venoms harbor a wealth of diverse anticancer active components, serving as a valuable resource for the development of natural antitumor drugs. AI-based computation and prediction models enable rapid screening of extensive active peptides. In this study, the anticancer activity of seven peptides was predicted using our previous deep learning model. Further verification experiments confirmed that Lpep3 can selectively and efficiently inhibit the growth of leukemia cells. Electron microscopy observations revealed cell shrinkage in morphology and honeycomb-like perforations on the cell membrane in the treated group. It is hypothesized that high-concentration peptides disrupt the cell membrane and increase cell permeability, which was confirmed by trypan blue staining and Calcein-AM/PI double-staining assays. Lpep3 induces the release of lactate dehydrogenase (LDH) and ATP in a concentration-dependent manner, further suggesting that this peptide disrupts the cell membrane. In addition, although Lpep3 does not affect the cell cycle of MV-4-11, it can induce cell apoptosis. Western blotting and RT-qPCR results showed that compared with the control group, the expression levels of Bax were upregulated, while the expression level of Bcl-2 protein was downregulated in the Lpep3 group. In vivo experiments demonstrated that Lpep3 has good biological safety, and compared with the control group, the Lpep3 group could inhibit the growth of tumor cells in mice. Collectively, Lpep3 is characterized by high potency and specificity and may serve as a promising lead compound for the development of anti-leukemia drugs. Full article

Background/Objectives: Respiratory tract infections (RTIs) remain a leading cause of morbidity worldwide and are frequently associated with the emergence of multidrug-resistant pathogens. In this context, natural compounds represent a valuable source of novel antimicrobial and immunomodulatory agents. The present study aimed to evaluate the antibacterial, anti-inflammatory, and antioxidant activities of Protegol, a natural food supplement enriched in bioactive phytochemicals including hydroalcoholic extracts of propolis and hedge mustard (Sisymbrium officinale (L.) Scop.) aerial parts, together with honey, against clinically relevant bacterial strains and in cellular models of inflammation and oxidative stress. Furthermore, the ability of the multi-herbal formulation to alter the permeability of the bacterial cell wall was assessed. Methods: The antibacterial properties of Protegol were evaluated by determining its minimum inhibitory (MIC) and minimum bactericidal concentrations (MBC) against a panel of Gram-positive and Gram-negative bacteria, using the broth microdilution method. Cell wall permeability was investigated through the propidium iodide (PI) uptake assay. The anti-inflammatory potential was investigated in LPS-stimulated RAW 264.7 macrophages by measuring nitric oxide (NO) production with the Griess assay. The antioxidant activity was evaluated in BALB/3T3 fibroblasts exposed to hydrogen peroxide, using the DCFH-DA assay. Results: Protegol exhibited a broad-spectrum antibacterial effect, with MIC values ranging from 1.5 to 6.2 mg/mL and MBC values between 3.1 and 12.4 mg/mL. The strongest activity was observed against Staphylococcus aureus and Streptococcus pyogenes, including clinical isolates, while moderate efficacy was detected against resistant Klebsiella pneumoniae strains. PI uptake assays confirmed a dose-dependent disruption of bacterial membrane integrity, supporting a direct effect of Protegol on cell wall permeability. In macrophages, Protegol significantly and dose-dependently reduced NO release, lowering production to 44% at the highest concentration tested. In BALB/3T3 cells, Protegol markedly decreased ROS accumulation to 24% at the same concentration. Conclusions: Overall, the findings support the potential of Protegol as a natural adjuvant to the conventional therapies for respiratory tract health by counteracting bacterial pathogens, reducing inflammation, and mitigating oxidative stress, thereby supporting host defense mechanisms in the context of respiratory tract infections. Full article

6:2 chlorinated polyfluoroalkyl ether sulfonic acid (F-53B), a substitute for perfluorooctane sulfonate (PFOS), is widely used as a mist suppressant in the electroplating industry. With the implementation of PFOS regulations, the use of F-53B has correspondingly increased, and it is now detected in various environmental matrices. However, toxicological information on F-53B remains incomplete and insufficient for environmental risk assessment. In this study, we systematically investigated, for the first time, the toxicity and underlying mechanisms of action of F-53B to Escherichia coli. The results showed that the 24 h half-maximal growth inhibition concentration (IC₅₀) of F-53B was 23.56 mg/L, suggesting that F-53B may exhibit higher toxicity to E. coli than PFOS. Analyses of cell surface hydrophobicity, membrane permeability, membrane composition, and scanning electron microscopy (SEM) images showed that F-53B adsorbed onto the cell surface, altered membrane properties, and ultimately disrupted cell morphology. Increased intracellular levels of reactive oxygen species (ROS) and malondialdehyde (MDA), along with decreased activities of superoxide dismutase (SOD) and catalase (CAT), indicated enhanced oxidative stress induced by F-53B in E. coli. Furthermore, the alkaline comet assay demonstrated that F-53B exposure caused DNA damage. Taken together, the toxicity of F-53B to E. coli can be attributed to cell morphological disruption, oxidative stress, and DNA damage, ultimately leading to cellular inactivation or death. These findings advance our understanding of the cytotoxicity of F-53B in microorganisms. Full article

Protein–protein interactions (PPIs) are fundamental to viral replication, regulating transcription, assembly, and genome packaging. Despite their biological importance, few FDA-approved therapeutics directly target these complexes. The split luciferase complementation assay (SLCA) is a quantitative bioluminescence system to measure protein–protein interactions in vitro after the proteins in question have been fused in-frame to N and C luciferase fragments. The SLCA can be performed both in vitro using purified protein components and in live cells, as the luciferase substrate luciferin is cell-permeable, allowing detection of protein interactions in intact cells. Assay performance, however, depends on the expression level and stability of the fusion proteins used. SLCA has been successfully applied to target Rev–Rev interactions in human immunodeficiency virus type 1 (HIV-1) for high-throughput small-molecule screening, establishing a proof-of-concept to target other parts of the viral life cycle. The system can be extended to other pathogens that currently do not have specific antiviral therapies such as HIV-1 Tat–cyclin T1, Capsid dimerization in Dengue virus, capsid interactions in equine encephalitis viruses, capsid assembly in Epstein–Barr virus, and nucleoprotein oligomerization in rabies virus. These applications demonstrate how the assay’s ability to quantify multimeric structural interactions is essential to viral replication, providing an avenue to identify small-molecule inhibitors that prevent viral replication and spread. Although there are challenges to protein stability and assay optimization, the sensitivity and adaptability of the SLCA has broader implications in virology to accelerate antiviral drug development. Full article

The reduced graphene oxide (rGO) combination in association with the single-walled carbon nanotubes (SWCNTs) in a dispersion minimizes the number of carbon particles to obtain a hydrogel with the same level of specific conductivity. When developing neuroimplants intended to restore damaged neural networks or modulate pain transmission, biocompatibility and the permeability of stimulating currents are key requirements. The specific conductivity of the resulting hydrogels with the addition of different carbon nanoparticles was 19 mS/cm (1-SWCNTs), 17 mS/cm (2-rGO), and 35 mS/cm (3-SWCNTs/rGO). The results confirm the possibility of regulating the degradation time. Colorimetric assay for assessing cell metabolic activity (MTT) assay using the Neuro 2A cell line showed sufficient biocompatibility for the amount of SWCNTs and rGO used. Full article

Background/Objectives: Drug efflux pumps represent a significant challenge that contributes to the development of antibiotic resistance in bacteria. This research aimed to evaluate the flavonoids apigenin, chrysin, glycitein, and hesperetin for their potential to inhibit efflux pumps in drug-resistant Escherichia coli. Method: The antibacterial activity of the flavonoids was assessed using minimum inhibitory concentration (MIC) and modulation assays. Dye accumulation and efflux assays were performed to evaluate effects on efflux pump function, while membrane permeability and biofilm formation assays were also conducted. Molecular docking was used to examine interactions between the flavonoids and the AcrB efflux transporter. Results: Although the flavonoids showed limited intrinsic antibacterial activity, they enhanced the effectiveness of erythromycin, ciprofloxacin, and clarithromycin against drug-resistant E. coli. Apigenin and hesperetin significantly increased dye accumulation and reduced dye efflux, indicating interference with substrate translocation through efflux pumps. All compounds exhibited no effect on inner membrane permeability, while apigenin, chrysin, and glycitein inhibited biofilm formation. Docking results showed that apigenin and chrysin bind favorably within the distal binding pocket of AcrB, forming hydrophobic and π–π interactions with key aromatic residues such as Phe610 and Phe628, with binding affinities of –8.8 to –8.9 kcal/mol. Conclusions: The results suggest that apigenin and chrysin have promising efflux-pump inhibitory potential in drug-resistant E. coli, supporting their possible role as adjuvants to improve antibiotic efficacy. Full article

Ionic Liquids (IL) are a unique class of molten salts, with specific formulations exhibiting antimicrobial properties. Several recent studies have highlighted the ability of ILs to form micelles, permeabilize the plasma membrane, and destabilize cellular structure, ultimately initiating cell death. Moreover, while these membrane-destabilizing properties are cytotoxic to most cellular organisms at high concentrations, their membrane destabilization capability at lower concentrations may lead to improvements in drug delivery for combinatorial therapies against specific microbes. Work presented in this study aimed to identify a synergistic relationship between ILs, 1-n-Hexyl-3-methylimidazolium chloride (HMIM[Cl]) and 1-Methyl-3-n-octylimidazolium chloride (OMIM[Cl]), and antifungal drugs (AF), Clotrimazole, Ketoconazole, Fluconazole, and Itraconazole, with the hypothesis that in a combinatory setting there should be improved AF efficacy against model fungal organisms: S. boulardii, S. cerevisiae, S. pombe, and C. albicans. Several complementary assays were used to identify the combined effects of IL + AF treatment, including Kirby–Bauer tests and minimum inhibitory concentrations (MIC) assays to establish antimicrobial effects, and flow cytometry to evaluate cell wall permeability. Finally, we demonstrate that at low concentrations, the ILs tested in this study are capable of improving the effectiveness of current antifungal compounds at concentrations not cytotoxic to human cells. Full article

The increasing demand for eco-friendly and functional packaging materials has driven research on biodegradable materials incorporating bioactive compounds. In this study, kefiran-based films (K; 3%) were developed and incorporated with grape pomace extract (GPE) at different concentrations (3K-0.5GPE, 3K-1.0GPE, and 3K-1.5GPE). The films were characterized based on their physicochemical, mechanical, antioxidant, and antimicrobial properties. It was found that the incorporation of GPE into the films increased the L*, a*, b*, and ΔE values, as well as the thickness, and improved UV radiation protection. FT-IR analysis revealed interactions between kefiran and the phenolic compounds of GPE, without altering the polymer structure. In addition, an increase in tensile strength and elongation at break was observed, evidencing a plasticizing effect of GPE, which also increased the water vapor permeability of 3K-1.5GPE. Solubility was not affected by the incorporation of GPE into the films. Regarding bioactive properties, the addition of GPE increased antioxidant activity and total phenolics. Antimicrobial assays showed activity only for the 3K-0.5GPE film against Listeria monocytogenes, with no activity against Escherichia coli. Overall, kefiran-based films containing GPE exhibit characteristics that position them as potential alternatives for sustainable, bioactive food packaging materials, thereby promoting the valorization of by-products from the wine industry. Full article

Background: The combination of manganese porphyrins (MnPs) and ascorbate (ASC) represents a promising redox-based therapeutic approach for selectively targeting cancer cells. We investigated the cytotoxic effects of two structurally distinct MnPs (MnTPPS and MnF₂BMet) with differing lipophilicity and potential membrane permeability in combination with ASC. Methods: Cancer cell lines (MCF-7, PANC-1, U87, T98G, AT-2) and normal human dermal fibroblasts (HDFs) were treated with MnTPPS and MnF₂BMet in the absence or presence of ASC. Viability, migration potential, and intracellular oxidative stress were assessed using single-cell methods. Results: MnPs alone exhibited no intrinsic cytostatic or cytotoxic activity, as confirmed by proliferation, viability, and motility assays. When combined with ASC, both MnTPPS and MnF₂BMet significantly enhanced ASC-induced oxidative stress, leading to lipid peroxidation, glutathione depletion, mitochondrial dysfunction, and cell membrane disruption. Time-lapse microscopy revealed rapid necrotic cell death under co-treatment. Catalase fully abolished cytotoxicity, indicating the essential role of hydrogen peroxide. In contrast, dehydroascorbate (DHA), which increases intracellular ASC levels, did not induce the same toxicity, suggesting that extracellular ROS generation contributes predominantly to the observed effects. Normal fibroblasts were minimally affected, supporting the MnPs–ASC system’s selectivity toward cancer cells. Conclusions: MnTPPS and MnF₂BMet enhance extracellular oxidation of ascorbate and subsequent ROS production, leading to selective oxidative-stress-mediated cancer cell death. This study supports the potential of MnPs–ASC redox catalysis as a complementary oxidative-stress-based anticancer strategy and highlights the need for further mechanistic and structure–activity investigations. Full article