Search Results (1,043)

Significant progress has been made in developing cell-based drug delivery systems that utilize the intrinsic biological properties of various cell types—erythrocytes, leukocytes, platelets, stem cells, and even spermatozoa—to improve drug targeting, bioavailability, and biocompatibility. This review presents an integrative analysis of the latest advances in cell-based drug delivery systems, focusing on their design, pharmacokinetics, cellular interactions, and therapeutic potential. We specifically focus on hybrid microrobots and membrane-coated nanocarriers as emerging biohybrid platforms. Despite these advances, translation to the clinical phase remains constrained by persistent limitations, such as immune clearance, loss of membrane integrity during cargo loading, limited tissue penetration of carrier cells, and manufacturing challenges. Finally, we highlight future directions, including CAR-cell combinations and artificial cell engineering, that promise to expand the clinical utility of cell-based drug delivery systems in oncology, infectious diseases, and regenerative medicine. Full article

Polymers and polymer composites offer versatile possibilities for engineering the physico-chemical properties of materials on micro- and macroscopic scales. This review provides an overview of polymeric and polymer-decorated particles that can serve as drug-delivery vectors: linear polymers, star polymers, diblock-copolymer micelles, polymer-grafted nanoparticles, polymersomes, stealth liposomes, microgels, and biomolecular condensates. The physico-chemical interactions between the delivery vectors and biological cells range from chemical interactions on the molecular scale to deformation energies on the particle scale. The focus of this review is on the structure and elastic properties of these particles, as well as their circulation in blood and cellular uptake. Furthermore, the effects of polymer decoration in vivo (e.g., of glycosylated plasma membranes, cortical cytoskeletal networks, and naturally occurring condensates) on drug delivery are discussed. Full article

The accelerating threat of antimicrobial resistance (AMR) demands transformative strategies that go beyond conventional antibiotic therapies. Nanoparticles (NPs) have emerged as versatile antimicrobial agents, offering a combination of physical, chemical, and immunological mechanisms to combat multidrug-resistant (MDR) pathogens. Their small size, surface tunability, and ability to disrupt microbial membranes, generate reactive oxygen species (ROS), and deliver antibiotics directly to infection sites position them as powerful tools for infection control. This narrative review explores the major classes, mechanisms of action, and biomedical applications of antimicrobial NPs—including their roles in wound healing, implant coatings, targeted drug delivery, inhalation-based therapies, and the treatment of intracellular infections. We also highlight the current landscape of clinical trials and evolving regulatory frameworks that govern the translation of these technologies into clinical practice. A distinctive feature of this review is its focus on the interplay between NPs and the human microbiota—an emerging frontier with significant implications for therapeutic efficacy and safety. Addressing this bidirectional interaction is essential for developing microbiota-informed, safe-by-design nanomedicines. Despite promising advances, challenges such as scalability, regulatory standardization, and long-term biosafety remain. With interdisciplinary collaboration and continued innovation, antimicrobial NPs could reshape the future of infectious disease treatment and help curb the growing tide of AMR. Full article

P-glycoprotein (Pgp) plays a significant role in the disposition of cardiac glycoside (CG) drugs across the cell membrane. The relatively narrow therapeutic indices of these drugs, coupled with the co-administration of drugs that inhibit Pgp’s transport mechanism, often cause an increased level of CG in the patient’s plasma, resulting in fatal arrhythmia. Therefore, understanding the underlying mechanism of the CG–Pgp interaction is necessary to circumvent Pgp-mediated transport and effectively design next-generation CGs. In this study, we conducted a comparative analysis to examine the interaction with Pgp and further understand the Pgp-mediated transport of digoxin, digitoxin, digoxigenin, and digitoxigenin. Through the drug-induced kinetic studies of Pgp, our findings suggest that each of the four drugs tested has a single binding site within Pgp. The CG–Pgp binding studies demonstrated that digoxin, digitoxin, and digoxigenin had relatively higher binding affinities. The CG-mediated conformational changes in Pgp indicated that each of the drugs shifts Pgp to an “outward-open” conformation in a nucleotide-dependent manner. STDD NMR indicated that the protons within the δ-lactone ring and the tri-D-digitoxose sugar moieties (glycones) predominantly interact with Pgp. Finally, a model was proposed for CG-induced Pgp-mediated ATP hydrolysis and transport by integrating our data with previously published Pgp-mediated CG transport results. Full article

Cytochrome P450 (CYP450) enzymes play an essential role in the metabolism of drugs, particularly in phase I metabolic reactions. In this article, we present a comprehensive review of fifteen selected enzymes belonging to the CYP450 family. The enzymes included in this analysis are CYP7A1, CYP3A4, CYP3A5, CYP2D6, CYP2E1, CYP2C8, CYP2C18, CYP2C9, CYP2C19, CYP2B6, CYP2A6, CYP2A13, CYP1B1, CYP1A1, and CYP1A2. We examined the influence of natural, polymorphic variations within their primary amino acid sequences on their enzymatic function and mechanisms of action. To begin, we compiled a dataset of naturally occurring polymorphic variants for these enzymes. This was achieved through a detailed analysis of entries in the UniProt database, as well as an extensive review of the current scientific literature. For each variant, we included commentary regarding its potential impact on enzyme activity or drug response, based on evidence observed in in vitro experiments, in vivo studies, or clinical trials. Particular emphasis was placed on how such polymorphisms might alter the metabolism of xenobiotics, thereby potentially affecting pharmacological outcomes. In this respect, the work represents the first comprehensive source in the scientific literature that systematically gathers and organizes data on CYP450 polymorphisms, including an assessment of their potential significance in processes mediated by these enzymes. A more detailed comparison of the polymorphism-related in vitro studies is devoted to CYP3A4, an enzyme that displays the largest fraction of clinically significant polymorphs. Secondly, we aimed to establish possible molecular explanations for why specific polymorphisms exhibit clinically or experimentally observable effects. To explore this, we performed a qualitative structural analysis of the enzymes, focusing on shared structural characteristics among the examined members of the CYP450 family. The results of this analysis demonstrate that there is no single universal mechanism by which polymorphisms influence the function of CYP450 enzymes. Instead, the mechanisms vary and may include alterations in the orientation of the enzyme within the lipid membrane, changes affecting the association or dissociation of substrates and products at the active site, structural stabilization or destabilization of the enzyme’s reactive centers, modifications in the way the enzyme interacts with its ligand, or alterations in the character of the interface involved in contact with its redox partner (electron transfer protein). Furthermore, among the polymorphisms that significantly impact enzyme function, mutations involving the substitution of arginine residues for other amino acids appear to be overrepresented. Full article

Isoeugenol is a phenylpropanoid that is commonly found in essential oils and has been commonly used as a flavoring agent in the culinary field and an anesthetic in fish. Yet despite its similarity to well-known eugenol, there is a lack of data regarding how isoeugenol would directly modulate neuronal excitability to interfere with pain signaling. Here, we studied the effects of isoeugenol on voltage-activated Na⁺ currents (I_Na) as a means of starting to close the gap regarding the inhibitory properties of isoeugenol on neuronal excitability. We used rat dorsal root ganglia neurons under whole cell voltage clamp for the isolation of I_Na.. We show that isoeugenol effectively inhibits I_Na fully, reversibly, and in a dose-dependent manner. Our detailed analysis also indicates the direct interaction of isoeugenol with voltage-gated Na⁺ channels (VGSC) is likely state-dependent, as the inhibitory activity is enhanced by membrane depolarization. This effect is beneficial for pain management, as the drug would act more effectively as neuronal activity is promoted by membrane depolarization. Our data indicates a direct inhibition of VGSC by isoeugenol might constitute the main mechanism whereby this phenylpropanoid produces analgesia. This study serves as a basis for future approaches to deeply investigate the therapeutic potential of this drug or its derivatives. Full article

Background: Accurate assessment of drug cytotoxicity in vitro is essential for preclinical evaluation of anticancer agents. Methodological parameters such as cell density and solvent concentrations can significantly influence the reproducibility and reliability of cell-based assay results. Objective: This study aims to optimize cell seeding density and evaluate the cytotoxic effects of common solvents (DMSO and ethanol) on different cancer cell lines, complemented by in silico analysis to elucidate underlying mechanisms. Materials and Methods: Six cancer cell lines (HepG2, Huh7, HT29, SW480, MCF-7, and MDA-MB-231) were seeded at different densities to determine the optimal cell seeding number ideal for cell viability assay at 24, 48, and 72 h. The cytotoxicity of DMSO and ethanol was assessed in these cell lines using an MTT assay at multiple time points. In silico docking studies were conducted to investigate the interactions between solvents and key proteins involved in apoptosis, membrane function, and metabolism. Results: A cell density of 2000 cells per well yielded consistent linear viability across cell lines and time points. DMSO at 0.3125% showed minimal cytotoxicity across all cell lines (except MCF-7) and time points; the cytotoxic effect at higher concentrations is variable depending on cell type and exposure duration. Ethanol exhibited rapid and concentration-dependent cytotoxicity, reducing viability by more than 30% at as low as 0.3125% concentration after 24 h. Docking analyses revealed that DMSO binds specifically to apoptotic and membrane proteins, suggesting a role in inducing apoptosis. In contrast, ethanol primarily interacts with metabolic proteins, consistent with its effect on membrane disruption and rapid cell death. Conclusion: DMSO at 0.3125% is a good choice as a solvent since it has low toxicity in most tested cell lines; however, the safe concentration limit is dependent on cell type and exposure duration. Ethanol exhibited higher cytotoxicity, necessitating careful concentration management. The in silico analysis supports these findings, indicating that DMSO interacts with apoptosis-related proteins, whereas ethanol primarily affects metabolic processes. These results highlight the importance of precise cell density optimization and solvents for reliable cytotoxicity assessment in cell-based assays. Full article

Objective: Visceral leishmaniasis (VL), a Neglected Tropical Disease caused by Leishmania donovani, remains insufficiently addressed by current therapies due to high toxicity, poor efficacy, and immunosuppressive complications. This study aimed to identify and characterize repurposed drugs that simultaneously target parasite-encoded and host-associated mechanisms essential for VL pathogenesis. Methods: Two complementary in silico drug repurposing strategies were employed. The first method utilized electron–ion interaction potential (EIIP) screening followed by molecular docking and molecular dynamics (MD) simulations targeting two L. donovani proteins: Rab5a and pteridine reductase 1 (PTR1). The second approach employed network-based drug repurposing using the Drugst.One platform, prioritizing candidates via STAT3-associated gene networks. Predicted drug–target complexes were validated by 100 ns MD simulations, and pharmacokinetic parameters were assessed via ADMET profiling using QikProp v7.0 and SwissADME web server. Results: Entecavir and valganciclovir showed strong binding to Rab5a and PTR1, respectively, with Glide Scores of −9.36 and −9.10 kcal/mol, and corresponding MM-GBSA ΔG_bind values of −14.00 and −13.25 kcal/mol, confirming their stable interactions and repurposing potential. Network-based analysis identified nifuroxazide as the top candidate targeting the host JAK2/TYK2–STAT3 axis, with high stability confirmed in MD simulations. Nifuroxazide also displayed the most favorable ADMET profile, including oral bioavailability, membrane permeability, and absence of PAINS alerts. Conclusions: This study highlights the potential of guanine analogs such as entecavir and valganciclovir, and the nitrofuran derivative nifuroxazide, as promising multi-target drug repurposing candidates for VL. Their mechanisms support a dual strategy targeting both parasite biology and host immunoregulation, warranting further preclinical investigation. Full article

Caffeine is a widely consumed psychoactive compound known to influence drug metabolism and efficacy through interactions with key enzymes such as cytochrome P450 3A4 (CYP3A4). This study investigates the molecular impact of caffeine on the binding behavior of imatinib, a first-line BCR-ABL tyrosine kinase inhibitor, using molecular docking simulations. Structural optimization and lipophilicity analyses were conducted using HyperChem, while docking was performed with HEX software (Version 8.0.0) against the CYP3A4 receptor (PDB ID: 1W0E). Two administration scenarios were evaluated: concurrent caffeine–imatinib complex formation and sequential administration with caffeine pre-bound to CYP3A4. The caffeine–imatinib complex exhibited a predicted increase in lipophilicity (logP = 3.09) compared to imatinib alone (logP = −1.29), which may indicate the potential for enhanced membrane permeability and tissue distribution. Docking simulations revealed stronger binding affinity of the complex to CYP3A4 (−350.53 kcal/mol) compared to individual compounds, and improved imatinib binding when CYP3A4 was pre-complexed with caffeine (−294.14 kcal/mol vs. −288.19 kcal/mol). Frontier molecular orbital analysis indicated increased reactivity of the complex (ΔE = 7.74 eV), supporting the hypothesis of altered pharmacodynamic behavior. These findings suggest that caffeine may modulate imatinib’s metabolic profile and therapeutic efficacy by enhancing receptor binding and altering drug distribution. The study underscores the importance of evaluating dietary components during drug development and therapeutic planning, particularly for agents metabolized by CYP3A4. Full article

Background: With the increasing shift in drug design away from classical drug targets towards the modulation of protein-protein interactions, synthetic peptides are gaining increasing relevance. The synthesis and purification of peptides via solid-phase peptide synthesis (SPPS) strongly rely on trifluoroacetic acid (TFA) as a cleavage agent and ion-pairing reagent, respectively, resulting in peptides being obtained as TFA salts. Although TFA has excellent properties for peptide production, numerous studies highlight the negative impact of using peptides from TFA⁻ salts in biological assays. Methods: Investigated peptides were synthesized via SPPS and the TFA⁻ counterion was exchanged for Cl⁻ via freeze-drying in different concentrations of HCl. Detection and quantification of residual TFA⁻ were carried out via FT-IR, ¹⁹F-NMR, and HPLC using an evaporative light-scattering detector (ELSD). A liposomal fluorescence assay was used to test for the influence of the counterion on the peptides’ passive membrane permeability. Results: All TFA⁻ detection methods were successfully validated according to ICH guidelines. TFA⁻ removal with 10 mM HCl was determined to be the optimal condition. No impact on peptide purity was observed at all HCl concentrations. Influences on permeability coefficients depending on peptide sequence and salt form were found. Conclusions: This study presents a systematic investigation of the removal of TFA⁻ counterions from synthetic peptides and their replacement with Cl⁻ counterions. Detected counterion contents were used to understand the impact of sequence differences, especially positive charges, on the amount and potential localization of counterions. Our findings emphasize the importance of counterion quantification and specification in assays with synthetic peptides. Full article

The escalating global challenges of antimicrobial resistance (AMR) and cancer necessitate innovative therapeutic solutions from natural sources. This study investigated the multifaceted therapeutic potential of pigment-enriched plant extracts. We screened diverse plant extracts for antimicrobial and antibiofilm activity against multidrug-resistant bacteria and fungi. Hibiscus sabdariffa emerged as the most promising, demonstrating potent broad-spectrum antimicrobial and significant antibiofilm activity. Sub-inhibitory concentrations of H. sabdariffa robustly downregulated essential bacterial virulence genes and suppressed aflatoxin gene expression. Comprehensive chemical profiling via HPLC identified major anthocyanin glucosides, while GC-MS revealed diverse non-pigment bioactive compounds, including fatty acids and alcohols. Molecular docking suggested favorable interactions of key identified compounds (Cyanidin-3-O-glucoside and 1-Deoxy-d-arabitol) with E. coli outer membrane protein A (OmpA), indicating potential antiadhesive and antimicrobial mechanisms. Furthermore, H. sabdariffa exhibited selective cytotoxicity against MCF-7 breast cancer cells. These findings establish H. sabdariffa pigment-enriched extract as a highly promising, multi-functional source of novel therapeutics, highlighting its potential for simultaneously addressing drug resistance and cancer challenges through an integrated chemical, biological, and computational approach. Full article

This study used all-atom molecular dynamics simulations to investigate the structural dynamics of Ves a 1, a phospholipase from Vespa affinis venom, and its interactions within a lipid membrane environment, both alone and in the presence of the inhibitor voxilaprevir. Simulations conducted over 1 $\mathsf{\mu }$s for triplicate runs demonstrated system stability and convergence of structural properties. Our findings reveal that Ves a 1 engages in dynamic interactions with the lipid bilayer, involving key regions such as its lids, catalytic triad, and auxiliary site. The presence of voxilaprevir was observed to subtly alter these membrane interaction patterns and influence the enzyme’s catalytic area, reflecting the inhibitor’s impact within its physiological context. These results emphasize the crucial role of the lipid bilayer in shaping enzyme function and highlight voxilaprevir as a promising candidate for further inhibitor development, offering vital insights for rational drug design targeting membrane-associated proteins. Full article

Proto-oncogenes in the RAS superfamily play dual roles in maintaining cellular homeostasis, such as regulating growth signals and contributing to cancer development through proliferation and deregulation. Activating proto-oncogenes in vitro transforms cells, underscoring their centrality in gene regulation and cellular networks. Despite decades of research, poor outcomes in advanced cancers reveal gaps in understanding Ras-driven mechanisms or therapeutic strategies. This narrative review examines RAS genes and Ras proteins in both housekeeping functions, such as cell growth, apoptosis, and protein trafficking, as well as in tumorigenesis, integrating insights from human (HRAS, KRAS, NRAS), mouse (Hras, Kras, Nras), and Drosophila melanogaster (ras) models. While RAS mutations are tightly linked to human tumors, the interplay between their standard and oncogenic functions remains complex. Even within the same tissue, distinct cancer pathways—such as the mitogen-activated protein kinase (MAPK) and phosphoinositide 3-kinase (PI3K) pathways—can drive varied disease courses, complicating treatment. Advanced-stage cancers add further challenges, including heterogeneity, protective microenvironments, drug resistance, and adaptive progression. This synthesis organizes current knowledge of RAS gene regulation and Ras protein function from genomic alterations and intracellular signaling to membrane dynamics and extracellular interactions, offering a layered perspective on the Ras pathway’s role in both housekeeping and tumorigenic contexts. Full article

Background and Objectives: VPS26A, a core component of the retromer complex, is pivotal to endosomal trafficking and membrane protein recycling. However, its expression profile, prognostic significance, and clinical relevance in liver hepatocellular carcinoma (LIHC) remain unexplored. This study investigates the prognostic potential of VPS26A by extensively analyzing publicly available LIHC-related databases. Materials and Methods: Multiple databases, including TIMER, UALCAN, HPA, GSCA, KM Plotter, OSlihc, MethSurv, miRNet, OncomiR, LinkedOmics, GeneMANIA, and STRING, were used to evaluate VPS26A expression patterns, prognostic implications, correlations with tumor-infiltrating immune cells (TIICs), epigenetic modifications, drug sensitivity, co-expression networks, and protein–protein interactions in LIHC. Results: VPS26A was significantly overexpressed at both the mRNA and protein levels in LIHC tissues compared to that in normal tissues. This upregulation was strongly associated with a poor prognosis. Furthermore, VPS26A expression was both positively and negatively correlated with various TIICs. Epigenetic analysis indicated that VPS26A is regulated by promoter and regional DNA methylation. Additionally, VPS26A influences the sensitivity of LIHC cells to a broad range of anticancer agents. Functional enrichment and co-expression analyses revealed that VPS26A serves as a central regulator of the LIHC transcriptomic landscape, with positively correlated gene sets linked to poor prognosis. Additionally, VPS26A contributes to the molecular architecture governing vesicular trafficking, with potential relevance to diseases involving defects in endosomal transport and autophagy. Notably, miRNAs targeting VPS26A-associated gene networks have emerged as potential prognostic biomarkers for LIHC. VPS26A was found to be integrated into a highly interconnected signaling network comprising proteins in cancer progression, immune regulation, and cellular metabolism. Conclusions: Overall, VPS26A may serve as a potential prognostic biomarker and therapeutic target in LIHC. This study provides novel insights into the molecular mechanisms underlying LIHC progression, and highlights the multifaceted role of VPS26A in tumor biology. Full article

Sphingolipids (SLs) are a class of bioactive lipids characterized by sphingoid bases (SBs) as their backbone structure. These molecules exhibit distinct cellular functions, including cell growth, apoptosis, senescence, migration, and inflammatory responses, by interacting with esterases, amidases, kinases, phosphatases, and membrane receptors. These interactions result in a highly interconnected network of enzymes and pathways, known as the sphingolipidome. Dysregulation within this network is implicated in the onset and progression of cardiovascular diseases, metabolic disorders, neurodegenerative disorders, autoimmune diseases, and various cancers. This review highlights the pharmacologically significant sphingoid-based medicinal agents in preclinical and clinical studies. These include myriocin, fingolimod, fenretinide, safingol, spisulosine (ES-285), jaspine B, D-e-MAPP, B13, and α-galactosylceramide. It covers enantioselective syntheses, drug development efforts, and advances in molecular modeling to facilitate an understanding of the binding interactions of these compounds with their biological targets. This review provides a comprehensive evaluation of chiral pool synthetic strategies, translational studies, and the pharmacological relevance of sphingolipid-based drug candidates, offering a pathway for future research in sphingolipid-based therapeutic development. Full article