Search Results (9,358)

The ongoing emergence of New Psychoactive Substances represents a growing threat to public health, as newly synthesized compounds continuously enter the illicit drug market, evading standard detection methods and challenging regulatory frameworks. Among New Psychoactive Substances, nitazenes are potent non-fentanyl opioids associated with severe cases of intoxication. This study evaluated the genotoxic potential of metodesnitazene and etodesnitazene in the human TK6 cell line. Cells were exposed to increasing concentrations of studied compounds, with and without S9 metabolic activation system. Preliminary assessments and micronuclei frequency analyses were performed by flow cytometry in at least three independent experiments. Metodesnitazene induced an increase in micronuclei frequency starting from 12.5 μM (p < 0.05), whereas etodesnitazene induced an effect only at 50 μM. Metabolic activation increases micronuclei formation at higher concentrations of metodesnitazene 25 μM, but did not substantially affect the response to etodesnitazene. Both compounds also induced intracellular reactive oxygen species production, measured through a chemiluminescent-based bioassay, suggesting oxidative stress as a potential contributing mechanism. These findings highlight the need for compound-specific toxicological profiling to better anticipate the acute and long-term risks associated with nitazene consumption. Full article

Background: Polymeric drug-eluting films are promising platforms for local antibacterial delivery, but their release profiles depend strongly on the permeability and morphology of the barrier layer. Here, the previously proposed concept of additively manufactured PLACE (Printed Layered Adjustable Cargo Encapsulation) coatings was extended from "single orifice"-defined release toward porosity-assisted barrier control. Two conventional water-soluble porogens, polyethylene glycol (PEG) and polyvinylpyrrolidone (PVP), were compared with poly(2-ethyl-2-oxazoline) (PEOx), a hydrophilic polymer proposed as an alternative to PEG in biomedical formulations, but whose use as a leachable porogen has received little attention. Methods: Each porogen was introduced into the upper PLGA barrier of multilayer PLACE films. The resulting films were characterized for film formation, post-hydration morphology by SEM, release of methylene blue and vancomycin, and antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA). Results/Conclusions: PEG was poorly compatible with PLGA and mainly produced surface-localized defects rather than a barrier with controlled permeability suitable for prolonged delivery. PVP K17 provided sustained release at 10 wt.%, whereas 20 wt.% PVP caused burst-dominated release and stronger morphological disruption. PEOx formed developed porosity at lower loading and produced release regimes ranging from several days to approximately two weeks. Vancomycin-loaded films containing 5 wt.% PEOx enabled near-complete release over two weeks while preserving film integrity and showed pronounced early anti-MRSA activity. These results identify porogen selection as a key formulation step and support PEOx as a useful porogen for early high-output antibacterial PLACE coatings. Full article

Background/Objectives: Microtubule-targeting agents represent a pillar of cancer chemotherapy; however, their clinical utility is constrained by significant toxicity, pharmacokinetic instability, and susceptibility to multidrug resistance transporters. This study aimed to explore the impact of replacing substituted phenyl rings with a naphthalene moiety in sulfonamide-based colchicine-site ligands, with the goal of identifying new antiproliferative candidates with improved profiles. Methods: We designed, synthesized, and evaluated a library of 35 naphthalene sulfonamides bearing varied aryl groups and sulfonamide nitrogen substituents. We assessed the antiproliferative activity against multiple cancer cell lines. Mechanistic studies, including fluorescence microscopy, cell cycle analysis, and cell death assays, were performed to evaluate the effect of these compounds on microtubule polymerization dynamics and cell fate. Molecular docking and in silico pharmacokinetic profiling were carried out to support the proposed binding mode at the colchicine site and to assess drug-likeness. Results: Exclusively, compounds bearing a trimethoxyphenyl group showed antiproliferative activity in the submicromolar range, thus identifying it as a structural requirement. The most potent compound (2) reached double-digit nanomolar IC₅₀ values (67–104 nM) across multiple cancer cell lines. Microscopy confirmed intracellular disruption of microtubule polymerization. Unlike colchicine, these compounds did not induce canonical mitotic arrest but instead triggered apoptotic cell death. In silico analyses supported binding at the colchicine site and revealed favorable predicted pharmacokinetic properties. Conclusions: The naphthalene sulfonamides described herein demonstrate potent antiproliferative activity through a distinct mechanism compared to colchicine, and their favorable in silico profiles position them as promising candidates for further development as antitumor agents. Full article

Mitochondrial electron transport chain (ETC) dysfunction is a major driver of bioenergetic failure, redox imbalance, and drug toxicity, yet strategies to restore oxidative phosphorylation under ETC blockade remain limited. Redox-active small molecules could, in principle, shuttle electrons from NADH to distal ETC components and oxygen, thereby modulating both respiration and reactive oxygen species (ROS) formation. Here, we show that the enzyme-independent redox cycler phenazine methosulfate (PMS) rewires mitochondrial redox circuits and restores respiration in human glioblastoma cells and cell-free systems under ETC inhibition. At subtoxic concentrations, PMS acutely increased oxygen consumption and mitochondrial superoxide generation via NADH–PMS–O₂ redox cycling, while restoring mitochondrial membrane potential and ATP synthesis under ETC blockade, and shifting metabolism away from glycolytic lactate production. This profile is consistent with a protective redox-bypass role, distinct from the pro-apoptotic effects reported following high-dose, prolonged PMS exposure. The PMS-driven restoration of electron flow, mitochondrial membrane potential, and respiratory ATP synthesis under inhibition of Complex I (rotenone), III (antimycin A and myxothiazol), and/or IV (cyanide) is consistent with direct cytochrome c reduction, as demonstrated herein, and engagement of multiple ETC redox centers, including coenzyme Q₁₀. In metformin-treated cells, PMS reversed suppression of respiration and lactate accumulation, outperforming existing redox-bypass strategies. These findings identify PMS-driven redox cycling as a previously unrecognized chemical redox-bypass mechanism that both regenerates mitochondrial bioenergetics and reshapes ROS production, suggesting a potential approach to counteract drug- and toxin-induced mitochondrial dysfunction and to exploit redox vulnerabilities in cancer. Full article

Background/Objectives: Atrasentan is a selective endothelin A receptor antagonist (SERA) developed as a potential therapy for chronic renal diseases, including diabetic nephropathy and immunoglobulin A nephropathy. Despite this potential, understanding its metabolic bioactivation is essential for assessing the risks of drug-induced liver injury (DILI). However, the metabolic profile of atrasentan remains poorly characterized, and the mechanisms underlying its potential hepatotoxicity remain underexplored. Therefore, this study aims to investigate the metabolic pathways of atrasentan in human liver microsomes (HLMs) in the presence of nicotinamide adenine dinucleotide phosphate (NADP⁺), uridine diphosphate glucuronic acid (UDPGA), or glutathione (GSH). Methods: A liquid chromatography–high resolution mass spectrometry (LC-HRMS) coupled with a feature-based molecular networking approach was used to characterize metabolites. Characterization of the major metabolites was achieved through cytochrome P450 (P450) phenotyping with human recombinant P450 isoforms. Results: A total of eighteen metabolites were characterized through phase I and II metabolic reactions, including demethylenation, N-dealkylation, O-demethylation, hydroxylation, dehydrogenation, and glucuronidation. Atrasentan acyl glucuronide (M8) was confirmed as the predominant metabolite, and we also putatively annotated a catechol intermediate (M5) and its corresponding GSH conjugate (M15). Characterizing the GSH conjugate (M15) indicates that catechol intermediate (M5) can be further oxidized to a reactive ortho-quinone intermediate, which is subsequently trapped by GSH, suggesting the potential for a bioactivation mechanism. Reaction phenotyping demonstrated that the formation of M5 is catalyzed almost exclusively by the CYP3A subfamily. However, its direct translation to in vivo oxidative stress or covalent protein binding requires further studies. Conclusions: These findings demonstrate that feature-based molecular networking is a valuable strategy for metabolite characterization, underscoring the urgent need for further in vivo metabolism studies to definitively assess hepatotoxic risks associated with these reactive metabolites. Full article

Background/Objectives: Bursera bipinnata (DC.) Engl. resin (locally known as “copal blanco”) is traditionally used in Mexican ethnomedicine to treat infected wounds and skin inflammation, but the bioactive constituents underlying these effects remain largely uncharacterized. This study aimed to identify the compounds responsible for the wound-healing properties of the resin through bioactivity-guided fractionation and to evaluate their anti-inflammatory and antibacterial activities as complementary mechanisms supporting tissue repair. Methods: Crude resin (1.2–5.0 mg/mL) was assayed for anti-inflammatory activity in the TPA-induced ear-edema model in BALB/c mice, for antibacterial activity (MIC) against six clinically relevant strains, and for wound-healing activity in a murine excisional model with pirfenidone (PFD) as the reference drug (n = 5 per group). Bioactivity-guided fractionation followed by spectroscopic elucidation (¹H- and ¹³C-NMR, IR, EI-MS) led to the isolation of five constituents. Stigmasterol, the most active compound, was subsequently evaluated in an LPS-induced systemic inflammation model (oral administration, 20 mg/kg/day × 3 days) to characterize its immunomodulatory profile (TNF-α, IL-1β, IL-6, IFN-γ, IL-10) and in the wound-healing model to quantify local IL-6, IL-10 and TGF-β1 in skin homogenates. Results: The crude resin (5.0 mg/mL) achieved 99.63% wound closure at day 12 and a 49.08% reduction in TPA-induced ear edema, comparable to indomethacin (55.76%). The resin displayed selective antibacterial activity against Streptococcus pyogenes (MIC 125 µg/mL) and Salmonella typhimurium (MIC 250 µg/mL). Bioactivity-guided fractionation yielded the phytosterol stigmasterol (1), three lupane-type triterpenoids (lupeol acetate (2), lupenone (3), 3-epilupeol (5)), and the sesquiterpenoid caryophyllene oxide (4). At an equimolar 1 µM concentration, stigmasterol (1) shortened the mean wound-healing time to 10.3 ± 0.4 days, comparable to pirfenidone, and was associated with attenuation of systemic TNF-α, IL-1β and IL-6 peaks and with sustained local IL-10 and TGF-β1 expression. Histological assessment confirmed accelerated re-epithelialization and improved collagen organization. The resin was non-irritant in the OECD 404 acute dermal test (Primary Irritation Index = 0.00). Conclusions: These findings provide pharmacological evidence supporting the traditional use of B. bipinnata resin for wound healing. Stigmasterol (1), together with the lupane-type triterpenoids lupenone (3) and 3-epilupeol (5), were identified as key bioactive constituents. The data are consistent with a coordinated immunomodulation, in which stigmasterol is associated with reduced systemic pro-inflammatory signalling and increased local IL-10/TGF-β1 expression, an interpretation that should be confirmed in chronic and impaired wound-healing models. Full article

Background: Macrophage pyroptosis contributes substantially to sepsis-induced lung injury, yet effective therapeutic strategies remain limited. This study aimed to determine the protective effects of meloxicam, a non-steroidal anti-inflammatory drug, and the underlying mechanisms in this context. Methods:In vivo, CLP mice were treated with meloxicam (20 mg/kg). In vitro, LPS-primed macrophages were stimulated with ATP or nigericin in the presence or absence of meloxicam. Levels of pyroptosis-associated proteins (cleaved Caspase-1, mature IL-1β, GSDMD-NT), NLRP3 inflammasome assembly, and the CBP/TXNIP/p38 signaling axis were assessed by Western blot. Mitochondrial membrane potential (ΔΨm) and intracellular ROS were measured. Overexpression of COX-2, TXNIP, and CBP was also performed. Results: Meloxicam significantly improved survival, reduced lung injury, and suppressed pyroptosis-associated proteins in CLP mice. In vitro, meloxicam dose-dependently enhanced macrophage viability and reduced LDH, IL-1β, and IL-18 release. The protective effects of meloxicam were mediated by inhibition of NLRP3 inflammasome priming and assembly, disruption of NLRP3-ASC-pro-Caspase-1 complex formation, and suppression of ASC oligomerization. Meloxicam also inhibited the CBP/TXNIP/p38 axis, an effect reversed by TXNIP or CBP overexpression. Furthermore, meloxicam restored ΔΨm and reduced ROS accumulation; these effects were abrogated by the ROS inducer imiquimod. Importantly, the anti-pyroptotic effects of meloxicam were independent of COX-2 inhibition. Conclusions: These findings expand the pharmacological profile of meloxicam and support its repurposing as a therapeutic agent for sepsis-associated lung injury. Full article

Poly(ethylene glycol)-block-poly(ε-caprolactone) (PEG-b-PCL) copolymer micelles have emerged as promising drug delivery systems for enhancing the solubility and bioavailability of poorly water-soluble benzimidazole drugs. In this study, we prepared and characterized PEG-b-PCL micelles to encapsulate poorly water-soluble anthelmintics such as albendazole (ABZ) and fenbendazole (FBZ), with a focus on comparing their encapsulation behaviour, release profiles, and biological activity in cancer therapy. Drug-loaded micelles were analysed using dynamic light scattering (DLS), which revealed uniform nanosized micelles with a narrow polydispersity index (PDI). The morphology and size of both empty and drug-loaded micelles were examined using transmission electron microscopy (TEM), confirming that the micelles were spherical and consistent in size. Both drugs were efficiently encapsulated within the micellar core, demonstrating a high loading capacity. The release profiles of PEG-b-PCL micelles containing albendazole (ABZ) and fenbendazole (FBZ) at pH 7.4 were also evaluated. FBZ exhibited slower release kinetics compared to ABZ, likely due to its higher lipophilicity and stronger interactions with the hydrophobic PCL core, resulting in enhanced retention within the micelles. In contrast, ABZ had faster release kinetics. Finally, the in vitro MTT assays performed on the highly invasive triple-negative breast cancer (TNBC) cell line revealed the potential of these micelles as effective drug delivery systems. Full article

Neuroinflammation in multiple sclerosis (MS) is driven by the infiltration of myelin-reactive T cells into the central nervous system (CNS). Interferon-β (IFN-β) is one of the earliest disease-modifying treatments (DMTs) approved for MS and remains widely used in special populations (pregnant and elderly patients) owing to its favorable safety profile. However, the exact mechanism of action of this drug and reliable biomarkers of treatment response remain unclear. Transcriptomic profiling and data integration approaches offer powerful tools for investigating complex patterns of regulation and molecular mechanisms underlying therapeutic efficacy. In this study, we performed an integrative analysis of openly available transcriptomic datasets to characterize IFN-β-induced gene expression changes in MS patients. By combining data from large independent cohorts, we identified a 43-gene transcriptional signature consistently associated with IFN-β treatment across disease stages, including progressive MS. To explore the relevance of this signature, we cross-referenced the 43-gene signature with publicly available expression quantitative trait loci (eQTL) datasets to determine whether these genes could be influenced by known MS-associated risk variants highlighting Interferon-Induced Transmembrane Protein 3 (IFITM3) as a candidate molecular mediator of MS. This integrative approach provides new insights into IFN-β-driven immune modulation and supports the development of therapeutic strategies for MS. Full article

Postoperative delirium (POD) is an acute, reversible neurocognitive disorder characterized by confusion and altered consciousness. With the improvement in research methodologies and the introduction of innovative clinical drugs in recent years, a growing number of randomized controlled trials have been conducted. This article aims to conduct a comprehensive review of the efficacy of general anesthetics—including propofol, ciprofol, sevoflurane, ketamine, esketamine, dexmedetomidine, benzodiazepines, opioids, and lidocaine—in preventing and managing POD, based on randomized controlled trials published in the past five years. Propofol has advantages in preventing POD in pediatric patients. However, its efficacy compared with inhalational anesthetics still requires individualized evaluation in elderly patients. The novel drugs ciprofol and remimazolam exhibit favorable safety profiles and do not increase the risk of POD. The efficacy of dexmedetomidine shows variability across patient populations and surgical types. In addition, specific opioid drugs and lidocaine also demonstrate preventive potential when administered in a standardized manner. Full article

Marburg virus (MARV), a highly pathogenic member of the Filoviridae family, causes severe hemorrhagic fever with a high case fatality rate and currently lacks effective therapeutics. The viral entry process, mediated by the interaction between the MARV glycoprotein (GP) and host receptor C-type lectin domain family 4 member M (CLEC4M) (L-SIGN), represents a critical target for early-stage intervention. The active compounds from BindingDB and the decoy from DUDE were used. The RDKit was used for feature engineering. Machine learning models were trained on an initial dataset consisting of 56 active chemicals and 1232 decoys. Among the tested algorithms, the Random Forest model demonstrated superior performance, achieving the highest discriminative ability (AUC = 0.93, MCC = 0.88) on the test set. Virtual screening of 11,032 phytochemicals resulted in 120 predicted actives, of which 42 compounds satisfied drug-likeness criteria. Subsequent molecular docking identified three lead compounds (PubChem IDs: 42608095, 5281601, and 11243993) with moderate-to-promising binding affinities (−6.3 to −6.5 kcal/mol) toward the CLEC4M binding site. ADMET analysis revealed favorable pharmacokinetic and toxicity profiles for the selected lead compounds. DFT calculations of the three compounds highlighted their electronic stability and reactive nature, indicating that PubChem IDs 42608095 and 5281601 possess particularly stable electronic properties conducive to favorable target interactions. Combining machine learning models with molecular docking and Molecular Dynamics (MD) simulations worked well in finding promising phytochemical inhibitors. The MM/GBSA binding free energy calculations further confirmed binding affinities, with values of −10.83 and −11.08 kcal/mol, respectively, suggesting favorable complex stability. These findings provide a pathway for developing new antiviral agents against MARV, pending further experimental validation and optimization. Full article

Background/Objectives: Colistin is a complex polymyxin antibiotic with a narrow therapeutic window and significant interindividual pharmacokinetic variability, necessitating precise concentration monitoring. Current analytical methods often utilize colistin mixtures or require large sample volumes, potentially limiting the precision and resolution of individual component quantification. This study aimed to develop a sensitive and component-specific bioanalytical assay for the simultaneous quantification of colistin A and colistin B in human plasma. Methods: A liquid chromatography–tandem mass spectrometry (LC–MS/MS) method was developed using pure, component-specific reference standards to ensure rigorous independent quantification of each component. Analytes were efficiently extracted from a small volume of plasma (50 µL) using solid-phase extraction. Chromatographic separation was achieved on a C18 column with a total runtime of 4 min, and detection was performed using negative-ion multiple reaction monitoring (MRM). Results: Calibration curves showed excellent linearity over a range of 0.1–20 µg/mL for both colistin A and B (R² > 0.99). The precision (%CV ≤ 8.8%) and accuracy (86.4–105.7%) for both components met the predefined regulatory criteria. This method was clinically validated using 60 plasma samples from 15 patients, demonstrating its applicability for capturing individual concentration–time profiles within the clinically relevant range (0.323–19.579 µg/mL for colistin A and 0.065–6.132 µg/mL for colistin B). Conclusions: This validated bioanalytical assay enables precise clinical pharmacokinetic assessments in a high-throughput workflow using a small plasma volume. Therefore, it serves as a practical tool for therapeutic drug monitoring (TDM)-guided dose optimization and further clinical investigations of colistin therapy. Full article

Background/Objectives: Lipid-based nanocarriers have emerged as promising systems for improving the delivery of poorly soluble drugs by enhancing stability, bioavailability, and controlled release. This work aimed to formulate solid lipid nanoparticles (SLN) and nanostructured lipid carriers (NLC) containing ciprofloxacin (CIP) using solvent-free procedures. Methods: The systems were extensively characterized using dynamic light scattering (DLS), transmission electron microscopy (TEM), and atomic force microscopy (AFM) to study the nanoparticles in the solid state. Furthermore, in vitro drug release was evaluated, and mathematical modeling was applied to analyze the resulting release kinetics. Additionally, storage stability was assessed at 4 °C and 25 °C over a period of 8 months. Results: The results indicated that SLN with an average size of ~50 nm (SLN 50) and NLC with mean diameters of ~25, 50, and 100 nm (NLC 25, NLC 50 and NLC 100 respectively) were successfully prepared. DLS measurements showed narrow particle size distributions (PdI ≤ 0.2) and negative zeta potentials ranging from −3.7 to −7.7 mV. Encapsulation efficiencies were remarkably high for most systems, reaching ~98% for SLN 50, NLC 50, and NLC 100, while the smallest formulation (NLC 25) showed a lower efficiency (~80%). Both TEM and AFM confirmed the formation of spherical nanoscale structures consistent with the sizes determined by DLS. Release studies revealed a strong influence of particle size on kinetics: NLC 25 exhibited rapid release (~95% within 30 min), whereas NLC 100 showed a sustained profile (<20% after 6 h). Dissolution profiles were accurately described by the Lumped-Gonzo kinetic model (R² > 0.98), enabling estimation of dissolution efficiency. Conclusions: These findings confirm that lipid-based nanocarriers can be engineered to precisely control CIP release. Full article

Malassezia are commensal lipid dependent yeasts which can cause opportunistic skin infection. Topical imidazole antifungals such as clotrimazole and ketoconazole are the frontline treatment. However, the tendency of fungal infections to recur, combined with the emergence of multi-azole-resistant Malassezia isolates means that many patients have used these antifungal treatments repeatedly or for extended durations with limited efficacy. While the impact of single azole treatments has been studied, the ability of specific azoles to induce cross-resistance is unclear. Understanding the effect of prior exposure of one treatment on susceptibility to other antifungals is important in the selection of the appropriate treatment to avoid driving the evolution of greater resistance. We previously identified drug transporters from the ATP-Binding Cassette (ABC) and Major Facilitator Superfamily (MFS) to be upregulated on extended exposure to clotrimazole. In this study, we investigated the effect of extended clotrimazole, ketoconazole and fluconazole exposure on antifungal cross-resistance profiles and examined the expression of the MFS transporters OPT1 and FLR1 in resistance emergence. We observed that treatment with clotrimazole was associated with increased cross-resistance to other antifungals. Ketoconazole treatment caused elevated MICs in all tested antifungals that did not decrease after drug removal. These findings advance our understanding of fungal adaptive resistance mechanisms and inform improved antifungal strategies to mitigate resistance development. Full article

As part of efforts to identify genes associated with Trichomonas vaginalis resistance to 5-nitroimidazole drugs, thirty cryopreserved T. vaginalis isolates were revived and grown using Diamond’s TYM medium. Minimum lethal concentrations (MLCs) for metronidazole (MTZ), tinidazole (TDZ), and secnidazole (SEC) were determined using a drug susceptibility assay. Transcriptome profiling was performed for 15 MTZ-sensitive (MTZ-S, MLC < 50 µg/mL) and 15 MTZ-resistant (MTZ-R, MLC ≥ 50 µg/mL) isolates using next-generation RNA sequencing. Bioinformatics analyses identified differentially expressed genes (DEGs). Among the MTZ-R isolates, six exhibited low MLCs of 50 µg/mL, five had intermediate MLCs between 100 and 200 µg/mL, and four had high MLCs ≥ 400 µg/mL. Differential gene expression analysis identified 28, 140, and 73 significantly altered genes in low-, intermediate-, and high-level MTZ resistance groups, respectively, with predominantly upregulated expression patterns. The SEC-resistant (SEC-R) isolates exhibited 136 differentially expressed genes, whereas the TDZ-resistant (TDZ-R) isolates showed minimal transcriptional changes. Focused analyses of iron transport pathways revealed reduced expression of ZIP-family iron import genes, particularly TvZIP4 (TVAG_273550), the strongest predictor of resistance in elastic-net modeling (AUC = 0.795). Resistant isolates also demonstrated coordinated upregulation of iron–sulfur cluster assembly and hydrogenosomal protein-import pathways. Weighted gene co-expression network analysis (WGCNA) identified multiple resistance-associated transcriptional modules correlated with MTZ and SEC MLCs. A comparative transcriptomic–proteomic analysis revealed concordant upregulation of iron–sulfur cluster machinery but discordant regulation of hydrogenosomal cargo proteins, likely supporting a post-transcriptional restriction model. These findings provide a broader mechanistic framework for understanding 5-nitroimidazole resistance in T. vaginalis and identifying candidate biomarkers and pathways that may support future therapeutic and diagnostic development. Full article