Search Results (1,741)

Juvenile hormone (JH) analog insecticides are widely used in pest management because of their ability to disrupt insect growth and metamorphosis; however, the molecular mechanisms linking endocrine disruption to metabolic dysregulation remain incompletely understood. In addition to their established roles in diapause and developmental regulation, JH signaling pathways have also been implicated in carbohydrate and lipid metabolism. In the present study, we investigated the effects of two JH analogs, pyriproxyfen and hydroprene, on the migratory locust, Locusta migratoria, with particular emphasis on lipid metabolic regulation and the function of midgut-enriched fatty acid-binding protein gene (Mg-FABP). Bioassays were performed to evaluate insecticidal activity, and transcriptomic analyses were conducted to identify differentially expressed genes associated with endocrine signaling and lipid metabolism. Functional characterization of Mg-FABP was further performed using RNA interference (RNAi) and Oil Red O staining assays. In addition, the tertiary structure of LmMg-FABP was predicted using AlphaFold 3, and molecular docking analyses were carried out to investigate its interactions with fatty acid ligands. Both pyriproxyfen and hydroprene caused approximately 70% mortality in locust nymphs and induced significant transcriptional changes in pathways related to hormone signaling and lipid metabolism. Transcriptomic analysis revealed pronounced downregulation of Mg-FABP following JH analog exposure. RNAi-mediated silencing of Mg-FABP significantly reduced lipid droplet accumulation in the fat body, indicating that Mg-FABP plays an essential role in lipid transport and metabolic homeostasis in L. migratoria. Structural analyses further demonstrated that LmMg-FABP possesses a conserved tertiary structure highly similar to FABP homologs from other insect species. Molecular docking identified key amino acid residues involved in fatty acid binding and suggested that hydrophobic interactions are critical for ligand stabilization within the binding cavity. Collectively, our findings demonstrate that pyriproxyfen and hydroprene disrupt insect development not only through endocrine imbalance but also through perturbation of Mg-FABP-associated lipid metabolic pathways. This study provides new mechanistic insight into the coordinated interaction between hormonal signaling and lipid metabolism during JH analog exposure and identifies FABP-mediated lipid transport as a potential molecular target for the development of more selective insect growth regulators. Full article

Background: Antiretroviral resistance-associated mutations, within the broader context of HIV-1 genetic variability, represent a growing challenge for HIV-1 control, highlighting the need for continuous molecular surveillance and mechanistic understanding of drug resistance. This study aimed to characterize mutations in the pol gene associated with resistance to protease inhibitors and to explore their structural implications. Methods: Viral RNA was extracted from plasma samples of HIV-positive patients, and a 266 bp fragment of the HIV-1 pol gene was amplified by RT-PCR and sequenced using the Sanger method. Sequences showing ≥98% homology were aligned and analyzed using MEGA v11 and the Stanford HIV Drug Resistance Database to identify resistance-associated mutations, while viral subtypes were determined using COMET, jpHMM-HIV, and STAR tools. Amino acid sequences were used for structural modeling with AlphaFold, followed by molecular docking with Nelfinavir using the CB-Dock2 server. Results: Four samples exhibited resistance-associated profiles, including high-level, intermediate, and low-level resistance, with one isolate showing high-level resistance to multiple protease inhibitors. Structural analyses revealed that Nelfinavir preferentially binds to alternative hydrophobic cavities rather than the canonical catalytic site, lacking direct interactions with the Asp25/Asp25′ dyad. Conclusions: These findings suggest a structural mechanism of resistance based on non-canonical ligand binding that may impair effective protease inhibition. Full article

Per- and polyfluoroalkyl substances (PFASs) are persistent environmental contaminants whose mobility in soil and groundwater is strongly controlled by adsorption and desorption processes. In saturated clay-rich soils, these processes are complex because PFASs interact with hydrated mineral surfaces, organic matter, metal oxides, exchangeable cations, and pore-water constituents. This review synthesizes the current literature on PFAS adsorption and desorption in saturated soils, with an emphasis on clay mineralogy, mineral–water interfaces, pore-water chemistry, and electrochemical double layer (EDL) effects. PFAS retention is influenced by molecular properties such as chain length, functional head group, and charge state, as well as soil properties such as organic carbon content, clay mineral type, surface charge, cation exchange capacity, and Fe/Al oxide content. Longer-chain PFASs and sulfonate-based compounds generally show stronger retention, while shorter-chain PFASs tend to remain more mobile. This review focuses particularly on how an EDL affects PFAS behavior in saturated clay systems. Unlike dry clay surfaces, saturated clay surfaces are covered by structured water, exchangeable ions, and diffuse counterion layers. These hydrated interfacial conditions influence how closely anionic PFASs can approach negatively charged clay surfaces, how dissolved cations reduce electrostatic repulsion or promote cation-mediated binding, and how effectively short-range interactions such as hydrophobic association, van der Waals forces, hydrogen bonding, and surface association contribute to adsorption. Desorption is also emphasized because adsorption does not necessarily represent permanent immobilization. Changes in pH, ionic strength, cation composition, dissolved organic matter, or competing solutes can weaken retention and promote PFAS release. Overall, PFAS mobility in saturated clay-rich soils should be interpreted as a coupled interfacial process rather than simple partitioning to soil solids. Future work should better connect molecular-scale mechanisms, EDL behavior, adsorption–desorption experiments, and saturated transport studies to improve predictions of PFAS retention and long-term groundwater release. Full article

Mounting acaricide resistance in Tetranychus mexicanus (McGregor) (Acari: Tetranychidae), among the most damaging phytophagous mites in tropical and subtropical crops, has intensified the search for botanical alternatives. An oil-in-water nanoemulsion of Thymus vulgaris essential oil (TVEO-NE) was developed and evaluated for lethal and sublethal effects on adult females of T. mexicanus. TVEO, composed mainly of thymol (45%) and p-cymene (37%), was formulated by low-energy emulsification yielding stable dispersions (~200 nm; PDI < 0.25; zeta potential of −22.2 mV). At 30.0 mg a.i./mL, TVEO-NE caused 68.3% corrected mortality at 72 h and suppressed fecundity by ~44–52%; vehicle controls exerted only moderate effects, identifying the essential oil as the primary bioactive driver. Morphological examination revealed collapse of female idiosomata and disruption of excretory pellet architecture, corroborating the bioassay data. Molecular docking against a cathepsin L homology model revealed that thymol and p-cymene interact exclusively via hydrophobic contacts and display substantially lower ChemPLP fitness scores than the reference cysteine protease inhibitor E64, indicating weak predicted binding affinity and arguing against enzyme inhibition as the primary mechanism. Taken together, bioassay, morphological, and docking are consistent with supporting membrane partitioning as a plausible primary mode of action, positioning TVEO-based nanoemulsions as promising botanical tools for T. mexicanus management. Full article

Biokinetic complexities (plastic sorption, protein binding, and cellular accumulation) may cause large discrepancies between nominal and biologically effective concentrations of test compounds assessed by new approach methods (NAMs). This case study was performed to explore a generally applicable workflow that addresses biokinetic complexities in the context of NAM-based hazard testing for next-generation risk assessment (NGRA). The pesticide tebufenpyrad (TEBU) is a challenging test compound, as it (i) is hydrophobic, (ii) has an intracellular target (mitochondrial respiration), and (iii) is acting at low concentrations (susceptible to biokinetic complexities). In the newly established NeuriTox-M neurotoxicity assay, based on human dopaminergic (LUHMES) neuron cultures, TEBU showed toxic effects at 20 nM. Mass spectrometric analyses of various experimental setups showed that a large fraction (75% to >90%) of TEBU was adsorbed to plastic. This effect was strongly attenuated by albumin in the medium. Cells, cultured on plastic, were considered unsuitable to assess cellular uptake. Therefore, alternatives were explored: when cells were used as suspension cultures (3% v/v) in albumin-containing medium, analysis worked best. Under such conditions, the concentration ratio (cells/medium) of TEBU was around 10. Data from an in vitro distribution (VIVD) model were in good agreement with the measurements. VIVD predicted the unbound medium TEBU concentration (C_u) to be 2–3 orders of magnitude below the nominal concentration and the total cellular concentration to be 10–100-fold above. Standard cell culture assays showed that the medium albumin content indeed altered the TEBU toxicity threshold. More such studies are needed to embed biokinetics information into NGRA. Full article

Blue honeysuckle (Lonicera caerulea L.) is a polyphenol-rich berry increasingly recognized as a functional food ingredient for postprandial glycemic management. However, it remains unclear whether its polyphenols can modulate intestinal glucose transport in addition to inhibiting carbohydrate-digesting enzymes. In this study, blue honeysuckle polyphenol extract (BHPE) was characterized by UPLC-QTOF-MS/MS, and its effects on α-glucosidase activity and intestinal glucose transport were evaluated using enzyme kinetics, fluorescence quenching, molecular docking, and differentiated Caco-2 monolayers. A total of 24 phenolic compounds were tentatively identified, with anthocyanins and chlorogenic acid derivatives as the major constituents. BHPE exhibited a mixed-type, static-quenching inhibition of α-glucosidase (IC₅₀ = 75.05 μg/mL). Furthermore, molecular docking revealed that key constituents, including cyanidin-3-O-glucoside, chlorogenic acid, and proanthocyanidin B1, bind the enzyme via hydrogen bonding and hydrophobic interactions. In Caco-2 cell monolayers, BHPE reduced glucose transport by up to 51.56% under simulated postprandial conditions and coordinately downregulated SGLT1 and GLUT2 mRNA expression to 0.58- and 0.51-fold, respectively. These findings extend the bioactivity profile of blue honeysuckle polyphenols from enzyme-level inhibition to functional regulation at the intestinal epithelial barrier, highlighting their potential as multi-target natural ingredients for the attenuation of postprandial hyperglycemia. Full article

The Pacific oyster (Crassostrea gigas) is well known for its pronounced umami taste. Here the interaction between the T1R1/T1R3 taste receptor and three oyster-based peptides, namely, FLNQDEEAR (FR-9), EEFLK (EK-5), and FNKEE (FE-5), was investigated via molecular docking and molecular dynamics (MD) simulations, as well as molecular mechanics Poisson–Boltzmann surface area (MM–PBSA) and residue–residue contact score (RRCS) analyses. A full-length human T1R1/T1R3 heterodimer was constructed with AlphaFold3. MD simulations indicated that the binding of FR-9 led to a large structural fluctuation, a large radius of gyration, and a large solvent accessible surface; on the contrary, FE-5 yielded the most stable receptor–ligand complex. The MM-PBSA analysis showed that the binding free energies of the three peptides were in the order of FR-9 > EK-5 > FE-5. The RRCS analysis indicated that RRCS values per residue were in the order of FR-9 < EK-5 < FE-5, in line with the reported umami score, and that the highest taste score of FE-5 originated from the hydrophobic interactions between Glu301 (receptor) and Phe1 (ligand) as well as the salt bridges between arginine (Arg277 and Arg307, receptor) and glutamic acid (Glu4 and Glu5, ligand) residues. These findings show that structural stability and residue contact density were more informative than binding affinity for distinguishing the taste intensity of umami peptides. Full article

Background/Objectives: The present study estimated the potential therapeutic effects of Borassus flabellifer immature endosperm extract (BFE) on the metabolic disorders of diabetes and hypothyroidism using a mixed research design. Methods: Characterization of phytochemicals via GC-MS demonstrated a highly abundant list of bioactive compounds, and it encompassed phenolic derivatives, methylxanthines, fatty acids, and inositol-related compounds. Molecular docking indicated that the major phytoconstituents showed positive binding affinities to the most vital metabolism and endocrine receptors, namely, TRβ1, PPARγ, and AMP-activated protein kinase (AMPK). Notably, both compounds C1 and C2 were highly affined towards TRβ1 (−7.8 and −7.6 kcal/mol), which is attributed to interactions in the active site through hydrogen bonding and hydrophobic responses, which means that the identified compounds were found to have good predicted interactions with some metabolic- and thyroid-associated targets and could be used to form preliminary hypotheses for further mechanistic studies. The in vivo data showed that the disease-induced groups were marked by hyperglycemia, imbalance in thyroid hormones, and dyslipidemia, as well as liver, kidney, and heart dysfunction. BFE caused significant decreases in these changes, which were also observed through improvements in fasting blood glucose, T3, T4, and TSH; partial restoration of lipid profiles; and dampening of liver and kidney injury signalers. The cardiac risk indices were also reduced significantly after BFE administration. Positive changes in body weight gain, feed ratio, and metabolic ratio further reflected better physiological stability. Results: These findings were corroborated by histopathological analysis, which showed that the tissue architecture of the pancreas, liver, kidney, and heart had significantly recovered in the study. BFE still showed constant therapeutic activity even though the magnitude of response was attenuated when combined disease conditions were used. Conclusions: Comprehensively, the results indicate that BFE potentially plays a role in the amelioration of metabolic and endocrine abnormalities of diabetic and hypothyroid conditions. These observations should be regarded as hypothesis-generating, as further mechanistic and translational studies are needed to substantiate their biological relevance. Full article

Fruit and vegetable processing by-products, such as peels and pomace, are rich in antioxidant polyphenols and represent promising sources of functional ingredients, but how their galloyl-based polyphenols interact with starch remains insufficiently understood. In this study, corilagin with three non-free galloyl moieties and 1,2,3,4,6-O-pentagalloyl glucose with five free galloyl moieties were used as model polyphenols to clarify how galloyl moiety number and accessibility modulate their complexation with high-amylose maize starch (HAMS). Size-exclusion chromatography showed that both polyphenols preferentially complexed with amylose, while FTIR confirmed that complex formation occurred mainly through non-covalent interactions. The two polyphenols induced distinct changes in HAMS structure. Corilagin disrupted short-range order and produced no detectable crystalline structure, whereas 1,2,3,4,6-O-pentagalloyl glucose enhanced molecular order and induced V-type crystallization. Isothermal titration calorimetry revealed more binding sites but weaker affinity for corilagin, with thermodynamic signatures indicating hydrogen bonding and van der Waals interactions. By contrast, 1,2,3,4,6-O-pentagalloyl glucose showed stronger affinity and hydrophobic interaction-dominated binding. Molecular dynamics simulations further confirmed that 1,2,3,4,6-O-pentagalloyl glucose formed a more stable association with the amylose helix than corilagin. These results indicate that galloyl moiety characteristics markedly influence starch–polyphenol interaction mechanisms, providing guidance for the utilization of polyphenol-rich agro-processing by-products in functional starch-based foods. Full article

The Lysobacter capsici XL1 β-lytic protease (Blp) is a bacteriolytic enzyme that hydrolyzes peptide bonds in the interpeptide bridge of the peptidoglycan of Gram-positive bacteria, including antibiotic-resistant strains of pathogenic bacteria. The Blp has been extensively characterized. The only unexplored aspect is the mechanism by which this enzyme recognizes target cells. In this work, we demonstrated for the first time that the Blp structure contained a C-terminal subdomain that can be responsible for this interaction. Molecular modeling suggested a hydrophobic nature of the interaction between the Blp and peptidoglycan. Model mutant forms of the Blp, which have fewer hydrophobic areas in the C-terminal subdomain, also had fewer sites for potential interaction with the ligand. Wet lab experiments showed that these mutant Blp forms exhibited poorer binding to peptidoglycan and living Staphylococcus aureus 209P cells, resulting in decreased bacteriolytic and proteolytic activity. Amino acid residues N136 and Y160 in the C-terminal subdomain were identified and can be important for the interaction of the enzyme with target cells. Further research into the mechanism of target cell recognition by bacterial bacteriolytic proteases will enable the use of this knowledge to expand the specificity of action of these enzymes, including as antimicrobial agents for medical applications. Full article

Whey protein isolate (WPI) can assemble into supramolecular complexes with flavonoids via non-covalent interactions, although the underlying binding mechanisms remain not fully understood. In this work, the formation mechanism of the WPI–phloridzin (PHL) complex was systematically investigated using an integrated experimental and computational approach. High-performance liquid chromatography quantified the binding content of PHL as 1.3% (w/w). Isothermal titration calorimetry indicated that the process was entropy-driven and governed predominantly by hydrophobic and electrostatic interactions. Complementary circular dichroism spectroscopy and molecular dynamics simulations revealed that complexation induces modest conformational adjustments in the protein’s secondary structure. Collectively, this multi-scale analysis provides mechanistic insights into the dynamic formation of the WPI–PHL complex, offering theoretical insights into protein–flavonoid recognition. Full article

Background/Objectives: Chronic myeloid leukemia (CML) is primarily associated with the BCR:ABL1 fusion protein. Although tyrosine kinase inhibitors (TKIs) have markedly enhanced treatment outcomes, the development of agents with improved therapeutic characteristics remains necessary. The present work focused on the synthesis of a new series of thiazolone derivatives (F1-11) and the assessment of their anti-CML activity through inhibition of ABL tyrosine kinase (TK). Methods: The designed compounds were prepared through a multistep synthetic pathway involving the formation of a new chalcone intermediate (A), synthesis of a new pyrazoline carbothioamide intermediate (B), and cyclization with different aldehydes to produce the target new thiazolone derivatives (F1-11). Cytotoxic effects were investigated against K562 CML cells using the MTT assay. The lead compound was additionally evaluated in HL-60 AML cells and normal PBMCs. Apoptotic induction was analyzed using Annexin V/ethidium homodimer staining, whereas ABL TK inhibitory activity was measured through the ADP-Glo assay. Molecular docking studies were conducted to explore ligand interactions within the ATP-binding domain of ABL TK. Results: Among the synthesized molecules, F-4 demonstrated the strongest activity against K562 cells with an IC₅₀ value of 6.85 µM, close to that observed for imatinib (IC₅₀ = 5.20 µM). The compound showed reduced cytotoxicity toward HL-60 cells (IC₅₀ = 33.44 µM) and exhibited favorable selectivity toward PBMCs (SI = 13). Apoptosis studies revealed 51% early apoptotic cells and 43% late apoptotic cells following treatment. In the kinase assay, F-4 inhibited ABL TK activity by 39% at 10 µM and by 70% at 100 µM. Docking simulations suggested interactions with residues His361 and Asp381 in addition to nearby hydrophobic amino acids, although the interaction network was less extensive than that of imatinib. Conclusions: The findings identify F-4 as a promising new thiazolone-derived scaffold with selective anti-CML activity and notable ABL TK inhibitory potential. Additional structural optimization may further enhance its binding characteristics and therapeutic efficacy. Full article

Porcine blood meal-derived hydrolysate peptides and hemin are natural antioxidants, and the formation of peptide–hemin conjugates can synergistically improve antioxidant performance. Ultrasonic (US) treatment facilitates the binding of different molecules. Therefore, in this study, the effects of ultrasonic power treatments on the antioxidant activity and binding behavior of peptide–hemin conjugates were investigated. The spatial structure of the peptide–hemin conjugates was characterized using endogenous fluorescence spectroscopy, Fourier transform infrared (FT-IR) spectroscopy, and circular dichroism (CD) spectroscopy, respectively. The results demonstrated that the peptide–hemin binding rate reached the highest value of 91.63% at 400 W US power, with structural changes in conjugates from α-helix to random coil structures. Additionally, US treatment increased the surface hydrophobicity and reduced the enthalpy change in conjugates. The antioxidant capacity was greatly improved and peaked at 400 W US, where DPPH and ABTS radical scavenging rates exceeded 55% and 65%, respectively. This study provided a scientific basis for the high-value utilization of US treatment on porcine blood meal resources. Full article

Background: Helicobacter pylori is a globally prevalent gastric pathogen associated with chronic gastritis, peptic ulcer disease, and gastric adenocarcinoma. Its persistence within the gastric niche is strongly linked to biofilm formation, contributing to immune evasion and antibiotic therapy resistance. Methodology: In the present study, we investigated the antibiofilm potential of capsaicin, a natural phytochemical derived from Capsicum species, against H. pylori using experimental and computational approaches. Results: Capsaicin treatment significantly reduced biofilm biomass (up to 75.66 ± 4.00%), metabolic activity (up to 61.23 ± 6.88%), and cell surface hydrophobicity in a dose-dependent manner. Microscopic analyses revealed disrupted biofilm architecture and diminished extracellular polymeric substance at higher concentrations. Molecular docking analysis revealed that capsaicin interacts with target H. pylori proteins (GTP cyclohydrolase II, α-carbonic anhydrase, and urease) through stable hydrogen bonds and hydrophobic contacts. Molecular dynamics simulations further supported the stability of these complexes and demonstrated reduced structural fluctuations upon ligand binding. Free energy landscape analysis suggested ligand-induced conformational alterations in α-carbonic anhydrase, indicating possible structural effects associated with capsaicin interaction. Conclusions: Overall, the findings provide insight into the antibiofilm activity of capsaicin against H. pylori and highlight its potential as a natural adjunct strategy for combating biofilm-associated persistence and antimicrobial resistance. Full article

Sensors and biosensors designed for biomarker detection in biological samples often suffer from performance loss caused by surface fouling, interface blocking, and matrix interference. Although these effects are frequently discussed separately, in real sensing systems they are strongly interconnected and they determine analytical reliability, especially in body fluids like serum, plasma, whole blood, sweat, and other complex media. This review provides a practical and mechanism-oriented overview of how these processes originate, how they differ, and how they ultimately lead to signal drift, reduced sensitivity, false-positive responses, and shortened sensor lifetime. We first discuss the molecular origins of interface failure, including protein adsorption, conditioning film formation, nonspecific binding, ionic strength effects, pH fluctuations, viscosity-related diffusion changes, and electroactive interferents. The impact of these phenomena is then compared across major sensing platforms, including electrochemical, potentiometric, optical, capacitive sensors, field-effect transistors and wearable biosensors. A central part of this review focuses on practical prevention strategies already employed in real biomarker sensing platforms. These include hydration-driven antifouling coatings, zwitterionic and hydrogel interfaces, post-immobilization blocking with bovine serum albumin, mercaptohexanol and ethanolamine, ionophore and membrane engineering in ion-selective electrodes, hydrophobic solid-contact layers for water-layer suppression, regeneration workflows, membrane and microfluidic pre-treatment, and AI-assisted drift correction. By combining advances in materials engineering, surface chemistry, sample handling, and algorithmic correction, this review highlights strategies to improve sensor stability in complex biological fluids. Overall, it offers a practical guide for developing next-generation low-fouling, drift-resistant, and self-correcting sensing systems for reliable biomarker analysis at the point of care. Full article