Search Results (6,130)

Although the parental recombinant protein rLj-RGD3 exhibits antitumor activity, it carries immunogenicity risks owing to its large molecular size (13.5 kDa). We generated a genetically truncated mutant, rLj-RGD4 (6.27 kDa, four RGD motifs), which inhibited B16 melanoma cell proliferation, migration, and invasion in vitro. However, the in vivo efficacy and mechanisms of action remain unclear. Here, B16 xenograft mice were treated with rLj-RGD4 (5, 10, and 20 μg/kg i.p. daily for 14 days). Tumor growth was measured, and histopathology/apoptosis was evaluated using hematoxylin and eosin (HE), Masson’s dye, Hoechst, and TUNEL staining. Apoptotic pathways (mitochondrial, death receptor, and MAPK) were analyzed via Western blotting, whereas endocytosis mechanisms were explored using inhibitors (filipin III, NaN₃, cytochalasin D), and EGFR (epidermal growth factor receptor) interactions via fluorescence co-localization and phosphoprotein assays. The results demonstrated dose-dependent tumor growth inhibition (21.60–89.26% volume reduction, 41.03–86.51% weight reduction), with histological evidence of tissue loosening, fibrosis, and apoptosis. rLj-RGD4 induced apoptosis by activating the mitochondrial (Bax/Bcl-2 upregulation), death receptor (caspase-8 activation), and MAPK (JNK/p38 phosphorylation) pathways. Internalization was blocked by NaN₃ and cytochalasin D, indicating actin-dependent macropinocytosis. Direct EGFR binding was confirmed, accompanied by reduced EGFR expression and the inhibition of FAK/AKT/Src signaling. In conclusion, rLj-RGD4 exerts potent in vivo antitumor activity via two mechanisms: induction of multi-pathway apoptosis and EGFR-targeted suppression of pro-survival signaling. RGD4 exerts its antitumor function in vivo by targeting and co-internalizing with EGFR. Full article

Biliverdin (BV) and bilirubin (BR) are established endogenous antioxidants and immune modulators in other organ systems; however, their roles in the male genital tract remain undefined. The aim of this study was to quantify both bile pigments in human seminal plasma using a fluorescent protein biosensor and to examine their associations with basic semen parameters. We analyzed forty-two semen samples from men undergoing infertility evaluation. Biliverdin predominated over bilirubin in 88.1% of samples. Biliverdin concentration ranged from 51.8 to 611.2 nM, whereas bilirubin ranged from 19.7 to 240.7 nM. The mean total amounts per ejaculate were 1054 pmol for biliverdin and 280 pmol for bilirubin. The total amount of bilirubin in the ejaculate was positively correlated with total sperm count (Rs = 0.47; p = 0.028), whereas biliverdin showed no significant association (Rs = 0.21; p = 0.723). Oligozoospermic samples had significantly lower bilirubin concentrations (p < 0.001) and lower total bilirubin amounts (p < 0.005). Teratozoospermic samples exhibited significantly higher biliverdin concentrations (p < 0.05). This study provides the first simultaneous quantification of biliverdin and unconjugated bilirubin in human seminal plasma and identifies distinct associations with sperm quality. These findings suggest that bile pigments may reflect localized redox-related processes in the male genital tract and may influence male fertility potential. Full article

Elaeagnus mollis oilseed (EMO) meal is a protein-rich by-product that may serve as a novel source of food-derived α-glucosidase inhibitory peptides. This study aimed to obtain EMO peptide fractions with enhanced α-glucosidase inhibition and to clarify the activity, stability and mechanism of the most active fraction. Fourteen proteases were compared, and 3.350 acidic protease was selected to establish an optimized hydrolysis process. The resulting EMO hydrolysate showed an IC₅₀ of 9.11 mg/mL against α-glucosidase and no detectable cytotoxicity towards HEK-293T cells at 0.1–12.0 mg/mL. Ultrafiltration yielded four fractions, among which the 3–10 kDa fraction exhibited the highest inhibition and maintained substantial activity under acidic pH (2–6), −20–50 °C, NaCl ≤ 5% and simulated gastrointestinal digestion. Kinetic analysis indicated mixed-type inhibition, while fluorescence, circular dichroism and molecular docking suggested that peptides in this fraction bind near the catalytic site of α-glucosidase and induce local conformational changes. These findings support EMO-derived 3–10 kDa peptides as stable, non-cytotoxic α-glucosidase inhibitors with potential as functional ingredients for dietary management of type 2 diabetes. Full article

Nonfat dry milk (NFDM) powder was produced by spray drying a pulsed electric field (PEF)-treated solution of 48% (m/m) evaporated skim milk (ESM) that was treated with a field strength of 20 kV/cm and specific energy of 15 kJ/L at 150 L/h. PEF treatment induced reduction to particle size for whey proteins by 8.4% and casein micelles by 11.1% and increased conductivity by 10.6%. The PEF-treated ESM solution was less viscous than the non-PEF control (14.5% lower) and sedimentation was reduced by 40%. Increases to the tapped density (1.9%), solubility (4.7%), and emulsification stability (60%) of the NFDM were observed after PEF treatment. Evaluation of protein structure indicated no modification to the secondary structure, while minor changes to the tertiary structure were observed with increased fluorescence intensity and decreased transition temperatures. The reduction in casein micelle size for the PEF-treated ESM may be associated with the movement of minerals to the aqueous solvent. This study is the first to apply PEF technology to a highly concentrated ESM solution using a continuous flow commercial PEF system. The results of this study suggest that PEF technology may be beneficial to improving the dairy processing efficiency of ESM and product quality for NFDM. Full article

Lipid nanodiscs are synthetic nanoparticles capable of solubilizing lipophilic drugs and have been shown to improve the potency of the antifungal Amphotericin B (AmphB) against various fungal pathogens. In this study, the SpyCatcher–SpyTag covalent labeling system was used to couple AmphB-loaded Apolipoprotein A1 (ApoA1) lipid nanodiscs to the receptor domain of Dectin-1, which binds to β-1,3/1,6 glucans present in many fungal cell walls. Denaturing protein gel electrophoresis demonstrated that ApoA1-SpyTag003 lipid nanodiscs could be covalently labeled with SpyCatcher003-Dectin-1-superfolder GFP (sfGFP). In microtiter growth assays with Saccharomyces cerevisiae, Dectin-1 AmphB nanodiscs displayed an IC₅₀ 1.5-fold lower than uncoupled AmphB nanodiscs and 2.8-fold lower than AmphB-only controls. Nanodiscs without AmphB and SpyCatcher003-Dectin-1-sfGFP themselves did not inhibit yeast growth. Fluorescence microscopy showed that SpyCatcher003-Dectin-1-sfGFP binds to yeast cell walls and accumulated at hot spots, matching the budding scar enrichment pattern previously described for other Dectin-1 fusion proteins. Together these results indicate that Dectin-1 fusions can target AmphB-loaded lipid nanodiscs to fungal cell walls and improve drug delivery. The results here establish the use of a modular SpyCatcher–SpyTag coupling system for targeting drug-loaded lipid nanodiscs to different cells or tissues, thereby increasing drug retention at infection sites, increasing drug potency, and reducing harmful side-effects. Full article

Serum contains diverse proteins whose concentrations vary with pathological conditions such as cancer, liver disease, neurological disorder, and infections. Conventional methods like serum protein electrophoresis (SPEP) and enzyme-linked immunosorbent assay (ELISA) are gold standards for protein identification; however, they are time-consuming and can miss abnormal serum protein levels. Inspired by chemical nose sensing based on selective sensor–analyte interactions, we synthesized five pyrene-conjugated fluorescent polymers (PFPs) with distinct side-chain head groups to construct a multichannel fluorescence sensor array. These polymers were screened for sensitivity to changes in serum protein levels using linear discriminant analysis (LDA), a machine learning method. This process led to the successful discovery of two PFPs that effectively detect protein level fluctuations. These PFPs provided a sensitive sensor array capable of generating a high-content response pattern (fingerprint) with six fluorescence channels. This sensor array successfully discriminated protein level fluctuations in serum with 98% jackknife classification accuracy and 95% unknown identification accuracy. This polymer sensor array holds strong potential as a diagnostic tool for serum-based samples and can be extended to other applications related to protein identification. Full article

Fabrazyme (agalsidase beta) is a therapeutic enzyme whose clinical efficacy is contingent upon its complex N-glycosylation patterns. Nevertheless, comprehensive glycosylation profiling remains challenging due to high site-specific heterogeneity. To address this, three orthogonal liquid chromatography–mass spectrometry (LC-MS) approaches were employed: (1) released N-glycan analysis with fluorescence detection and MS annotation, (2) site-specific glycopeptide mapping, and (3) intact protein MS. The released glycan profiling method was validated for reproducibility, intermediate precision, and inter-laboratory transferability, thereby enabling reliable separation and quantification of neutral, phosphorylated, and sialylated species. Glycopeptide mapping revealed distinct site-specific distributions: N108 was found to predominantly carry sialylated complex glycans; N161 was enriched in phosphorylated oligomannose structures; and N184 displayed the highest heterogeneity, including bisphosphorylated and sialylated glycans. Intact protein analysis was performed on both intact and desialylated Fabrazyme, thereby enabling confirmation of glycan assignments. Desialylation reduced spectral complexity, thereby facilitating accurate mass matching with a combinatorial library generated from glycopeptide-level data. The complementary use of these three analytical levels provides a comprehensive view of Fabrazyme glycosylation, offering a robust reference for quality control and biosimilar development. Full article

Protein glycation is a nonenzymatic modification that links sugar chemistry to molecular aging and chronic disease. Sequential reactions involving Schiff bases, Amadori products, and reactive α dicarbonyl intermediates generate advanced glycation end products (AGEs) that irreversibly alter protein structure and function. AGEs also act as ligands for the receptor for advanced glycation end products (RAGE), initiating oxidative stress, inflammation, and tissue remodeling. This review synthesizes the molecular pathways of AGE formation, their structural diversity, and the biological factors influencing glycation kinetics. Advances in analytical detection methods—including fluorescence spectroscopy, LC–MS/MS, and immunochemical approaches—are highlighted for their role in monitoring AGE accumulation. Particular attention is given to the contribution of glycation to diabetes, cardiovascular disease, neurodegeneration, and cancer, alongside emerging therapeutic strategies to limit AGE formation or block AGE–RAGE signaling. Glycation thus represents a central mechanism in human disease pathogenesis and an emerging therapeutic frontier. Full article

Bisphenol A (BPA) has long been used in plastics, resins, and food packaging materials; however, extensive research has demonstrated its reproductive, developmental, and endocrine-disrupting effects. Consequently, BPA has been increasingly restricted and replaced with structural analogues. Among these, tetramethyl bisphenol F (TMBPF) has emerged as one of the most widely used substitutes, particularly in epoxy resins and food-can coatings. Although initially regarded as a safer alternative, accumulating evidence suggests that TMBPF may exert multiple toxicological effects, raising concerns about its potential developmental neurotoxicity. The present study aimed to investigate the neurodevelopmental effects of TMBPF using both in vitro and in vivo approaches. First, a developmental neurotoxicity assay employing Sox1−GFP mouse embryonic stem cells was used to evaluate cytotoxicity using the cell counting kit-8 assay and neural differentiation based on green fluorescent protein (GFP) fluorescence intensity. The results indicated developmental neurotoxic potential according to the established discrimination index. Subsequently, pregnant and lactating mice were exposed to TMBPF daily from gestational day 10.5 to postnatal day 20, and their offspring were assessed for behavioral performance as well as changes in the expression of neurodevelopment-related genes in the brain. Behavioral analyses encompassed multiple domains, including memory and learning, social behavior, anxiety-related responses, and spontaneous locomotor activity, suggesting alterations in these functional outcomes. Molecular analyses further demonstrated changes associated with dopaminergic and cholinergic signaling, synaptic plasticity, neuronal activity markers, neuropeptides, and inflammatory pathways. Collectively, these findings provide the first evidence in a mammalian model that maternal exposure to TMBPF may influence offspring neurodevelopment. These findings suggest potential implications for human exposure to TMBPF, particularly through food-contact materials, and warrant further mechanistic and dose–response studies. Full article

Background: Rabies is a highly fatal zoonotic disease that causes approximately 59,000 human deaths worldwide each year. Current inactivated rabies vaccines require multiple doses and are associated with high costs. The full-length rabies virus glycoprotein (RVG), a membrane protein, exhibits substantial instability in its trimeric structure during recombinant expression. This instability makes it difficult to obtain high-purity, correctly folded antigens. Objectives: This study focuses on the preparation of a full-length recombinant RVG subunit vaccine candidate expressed in a glycoengineered Pichia pastoris system with mammalian-like glycosylation. Methods: The full-length RVG gene (including the transmembrane domain and cytoplasmic tail) from the Challenge Virus Standard-11 (CVS-11) strain was codon-optimized and inserted into the pPICZαA vector to construct the recombinant expression plasmid pPICZαA-RVG. The plasmid was transformed into glycoengineered Pichia pastoris X33-7 (low-mannose type) by electroporation for inducible expression. The target protein was purified by nickel affinity chromatography, anion-exchange chromatography, and Superdex-200 size-exclusion chromatography. The structural characteristics of the purified protein were analyzed by dynamic light scattering (DLS) and transmission electron microscopy (TEM). The purified antigen was formulated with the adjuvants AS03 or MF59. BALB/c mice (n = 5 per group) were immunized intramuscularly following a four-dose schedule (days 0, 7, 14, and 28). Antigen-specific IgG antibody titers were measured by ELISA, and neutralizing antibody titers were determined using the rapid fluorescent focus inhibition test (RFFIT). Results: Glycoengineered Pichia pastoris yeast strains expressing wild-type RVG (RVG-WT) or a mutant variant (RVG-M6: R84S, R199S, H270P, R279S, K300S, and R463S) were successfully constructed. The purified RVG antigen formed nanoparticles with an average particle size of approximately 75 nm. Immunized mice generated robust RVG-specific IgG responses, with titers reaching approximately 6.31 × 10⁵ for RVG-WT after the fourth immunization, compared to 3.16 × 10³ for RVG-M6 and 5.62 × 10³ for the RVG-WT-PEG control. Two weeks after the fourth immunization, RVG-WT formulated with AS03 or MF59 induced significant neutralizing antibody responses compared with the control group (p < 0.0001 and p < 0.01, respectively). The neutralizing antibody titers reached 1:79.43 in the AS03 group and 1:33.11 in the MF59 group, whereas the WT-PEG + AS03 control group showed a low titer of 1:3.72. In contrast, RVG-M6 formulated with MF59 failed to induce detectable neutralizing antibodies (1:3.02). Furthermore, RVG-WT + AS03 induced significantly higher neutralizing antibody responses than the WT-PEG + AS03 control group (p < 0.0001), and a significant difference was also observed between the RVG-WT + MF59 and RVG-M6 + MF59 groups (p < 0.01). Conclusions: The glycoengineered Pichia pastoris expression system successfully produced uniform full-length rabies virus glycoprotein nanoparticles with high purity. When formulated with the AS03 adjuvant, RVG-WT induced high-titer neutralizing antibodies in mice, suggesting a promising strategy for the development of recombinant subunit vaccines against rabies. However, this study is limited by the absence of challenge studies and validation in target animal species, which will be further investigated in future work. Full article

Biofouling remains a critical challenge in membrane bioreactors (MBR), which is primarily caused by the production of extracellular polymeric substances (EPS) as an initial step in biofilm formation. This still limits their widespread application in wastewater treatment. In the past decades, much research has been carried out to understand and consequently reduce biofouling in MBR. More recent studies have focused primarily on inhibiting the release of EPS by applying quorum quenching (QQ) to control biofouling in MBR. This study presents the first investigation of the QQ potential of Rubellimicrobium mesophilum and its effects on biofilm inhibition by EPS reduction, which is demonstrated for MBR operated with submerged flat sheet (PTFE, PS) and hollow fibre polyvinylidene fluoride (PVDF) membranes operated in parallel for 114 days. The QQ effect has a significant impact on the reduction in biofilm thickness on PTFE membranes by 45% and on PS membranes by about 47%, respectively. Additionally, the performance of PVDF was improved by 287.5%. Similarly, the total protein concentration on the PTFE membranes was reduced by 57%, while on the PS membranes, the reduction was 78%. In mixed liquor, protein reduction was 55%, indicating its effectiveness in controlling biofouling over extended operation. The biofilm formation was monitored by measuring the biofilm thickness via fluorescence microscopy and by analyzing the protein and sugar content of the developing biofilm and of the mixed liquor. All parameters indicated decreasing biofilm formation with increasing amounts of entrapped QQ bacteria, while the removal efficiency of organic compounds and ammonia remained similar between all MBRs. Full article

Background: Guanine-rich DNA regions can fold into G-quadruplex (G4) structures, which are prevalent in telomeres and oncogene promoters, making them attractive targets for anticancer therapeutics. Small molecules capable of selectively stabilizing G4 DNA can disrupt telomerase activity and oncogene expression, offering a promising strategy for cancer intervention. Methods: A rationally designed series of DPPZ–anhydride-conjugated ligands (1 and 2) and their corresponding quaternized derivatives (1-q and 2-q) were synthesized to investigate the combined effects of π-extension, bromine substitution, and cationic modification on DNA recognition. The synthetic strategy relied on the incorporation of a highly planar DPPZ–anhydride scaffold to enhance π-surface area, followed by selective quaternization to introduce permanent positive charge and reinforce electrostatic interactions with the DNA backbone. All compounds were fully characterized by NMR and spectroscopic methods. The DNA-binding properties of the ligands were systematically evaluated toward duplex (ds-DNA) and G-quadruplex (G4-DNA) structures using UV–Vis absorption titration, fluorescence intercalator displacement (FID) assays, and competitive dialysis experiments. Quaternization markedly enhanced intrinsic binding constants and significantly reduced DC₅₀ values, particularly for G4-DNA. While bromine substitution increased overall binding affinity, it did not substantially improve topology selectivity. Among the series, compound 1-q exhibited the most favorable balance between affinity and G4 selectivity. Results: The interaction of the compounds with BSA was quantified using Stern–Volmer quenching constants, which demonstrated a clear trend of enhanced quenching efficiency upon modification. The binding strength followed a descending order of 1-q > 2-q > 1 > 2, highlighting the superior performance of the first series over the second. These findings indicate that the structural features of 1-q facilitate a more robust interaction within the hydrophobic pockets of the protein. Conclusions: Overall, the results demonstrate that strategic π-conjugation combined with electrostatic reinforcement provides an effective approach for the development of topology-selective DNA-binding ligands. Full article

Gardenia jasminoides Ellis is a commercially important medicinal and ornamental plant; however, its functional genomics remain poorly understood because of the lack of efficient cell-based research tools. To address this limitation, we established an optimized method for isolating viable protoplasts from petal and mesophyll tissues of G. jasminoides and developed a polyethylene glycol (PEG)-mediated transient expression system. For petal protoplast isolation, the optimal enzyme combination consisted of 3.0% cellulase R-10 and 1.0% macerozyme R-10 supplemented with 0.5 M D-mannitol, yielding 5.26 × 10⁶ protoplasts per gram fresh weight (FW) with 80.63% viability. For mesophyll protoplast isolation, 1.5% cellulase R-10 and 0.5% macerozyme R-10 supplemented with 0.5 M D-mannitol produced 8.75 × 10⁶ protoplasts g⁻¹ FW with 84.55% viability. PEG-mediated transient transformation was optimized at 20% PEG4000 for petal protoplasts and 40% PEG4000 for mesophyll protoplasts, resulting in efficient GFP expression. This system was successfully applied to subcellular localization analyses of floral regulatory proteins (GjAP3, GjPI, and GjSEP) and defense-related proteins (GjNPR1 and GjTGA2), as well as to the validation of protein–protein interactions between GjSEP and GjPI and between GjNPR1 and GjTGA2 using bimolecular fluorescence complementation and yeast two-hybrid assays. Collectively, these results establish a reliable and species-specific protoplast-based platform for rapid functional characterization of genes in G. jasminoides, providing an effective tool for future studies on gene regulation, metabolic engineering, and molecular breeding in this horticultural plant species. Full article

Background: Crimean-Congo hemorrhagic fever (CCHF) is a severe tick-borne viral disease with a high fatality rate, and no licensed vaccines are currently available. The nucleoprotein (NP) of the Crimean-Congo hemorrhagic fever virus (CCHFV) plays a critical role in viral replication and immune recognition, making it a promising target for vaccine development. This study aimed to design and evaluate a multiepitope recombinant DNA vaccine targeting the NP of CCHFV. Methods: Cytotoxic T lymphocyte (CTL) epitopes from the NP were predicted via immunoinformatics approaches and systematically assessed for antigenicity, allergenicity, toxicity, hydrophobicity, and global population coverage. The selected epitopes were incorporated into four DNA vaccine constructs driven by a cytomegalovirus promoter, adjuvanted with human β-defensin 3 (hBD3), and fused to the reporter protein mRuby3. The constructs were evaluated in vitro using a fluorescent reporter system designed to provide a readout of TCR signaling upon the co-culture of T lymphocytes with differentiated monocytic cells expressing antigens. In vivo immunogenicity and protective efficacy were assessed in BALB/c (exploratory pilot) and IFNAR^−/− mice, a highly susceptible model for viral infection. Cytokine responses were measured to assess immunogenicity. Results: In vitro assays showed predominantly antigen-independent T-cell activation, suggesting that nonspecific stimulation inherent to the reporter co-culture system likely obscured the detection of antigen-specific TCR signaling. In vivo analyses in BALB/c mice revealed that the constructs elicited only modest systemic cytokine profiles while CCHFV-specific IgG and IFN-γ secretion remained undetectable, indicating that antigen-specific T-cell and antibody responses were limited. In the IFNAR^−/− challenge model, several peptide groups achieved significant 2–3 log reductions in tissue viral RNA and infectious titers (p < 0.05 vs. sham). However, the observed viral modulations were insufficient to reach the protective threshold and did not translate to a survival benefit (0%). Conclusion: Despite a rational in silico foundation, the multiepitope DNA vaccine constructs demonstrated limitations in inducing potent, antigen-specific immunity across both mouse models. The lack of antigen-specific responses indicates limitations in epitope selection, construct design, and delivery strategies, requiring optimization of next-generation epitope-based vaccines. These findings highlight the complexity of translating computational epitope predictions into functional vaccines, and provide benchmark data as a framework to guide future optimizations. Full article

Homeobox protein MEIS2 has been strongly implicated in colorectal cancer (CRC) progression and metastatic potential, making its targeted inhibition a promising therapeutic strategy. However, recently developed MEIS inhibitors are limited by poor aqueous solubility, instability under physiological conditions, and insufficient intracellular accumulation, which restrict their clinical applicability. To overcome these challenges, a multifunctional hybrid nanoemulsome system was developed by integrating boron–silane-doped carbon dots (CDs) with chitosan via glutaraldehyde crosslinking, followed by emulsification with oleic acid and non-ionic surfactants (Span 80 and Tween 20/80) in the presence of a MEIS inhibitor (MEISi-2). The resulting composite exhibited high structural stability, excellent biocompatibility, and a drug encapsulation efficiency of 96.2%. Fourier-transform infrared spectroscopy (FTIR) and dynamic light scattering (DLS) analyses confirmed successful hybridization and the formation of nanoemulsions with an average particle size of approximately 320 nm following drug loading. The system demonstrated controlled drug release under physiological conditions. In vitro studies using HCT116 CRC and HaCaT healthy keratinocytes revealed effective cellular uptake and selective cytotoxicity. The intrinsic fluorescence properties of CDs enabled real-time monitoring of intracellular drug delivery via DAPI-channel imaging. Overall, this hybrid nanoemulsome platform provides a stable and efficient delivery system for MEIS inhibitors and represents a promising strategy for the treatment of CRC. Furthermore, this approach may be extended to other poorly soluble amphiphilic therapeutic agents. Full article