Biointerphases最新文献

Bioactive herbal extracts have garnered significant attention due to their multitarget regulation and low toxicity, yet their clinical applications are limited by poor solubility, low bioavailability, and insufficient targeting. This review systematically summarizes the pharmacological properties of terpenoids, alkaloids, flavonoids, polysaccharides, and other components, and explores their synergistic integration with biomaterials such as nanoparticle delivery systems, microneedles, and hydrogels. Functionalized nanocarriers enhance the stability and targeting efficiency of paclitaxel, berberine, and other bioactive herbal extracts. Microneedle technology leverages physical penetration and sustained-release mechanisms to achieve efficient transdermal delivery of bioactive herbal extracts (e.g., aconitine, curcumin, and similar agents). Smart hydrogels incorporating active molecules (e.g., baicalin and icariin) achieve spatiotemporal precision in wound healing and osteoarthritis treatment through pH-/enzyme-/reactive oxygen species-responsive release mechanisms. Additionally, the combination of herbal extracts with stents or bone cement expands their potential in cardiovascular and bone regeneration applications. While these integrated systems demonstrate synergistic effects in antitumor, anti-inflammatory, and tissue repair, challenges remain in scalable manufacturing, in vivo metabolic mechanisms, and long-term biosafety. Future research should integrate smart biomaterial designs and multiomics analysis to establish a comprehensive "component-carrier-efficacy" development framework, advancing the convergence of bioactive herbal extracts and modern medical science.

The disruption of protein structures by denaturants such as urea is well-documented, although the underlying molecular mechanisms are not yet fully understood. In this study, we employed molecular dynamics simulations to examine the effects of urea on the structural stability of bovine serum albumin (BSA) at concentrations ranging from 0 to 5M. Our results reveal that urea induces a dehydration-rehydration cycle by displacing and partially substituting water molecules in BSA's hydration shell. At lower concentrations, urea decreases protein-water hydrogen bonding while enhancing protein-urea interactions. At higher concentrations, urea tends to aggregate, which limits direct interactions with the protein, promotes rehydration, and leads to alterations in the tertiary structure, although the secondary structure remains largely preserved. These findings offer mechanistic insights into urea-induced protein denaturation and stability.

An immunological atomic force microscopy technique was used to recognize fibrinogen adsorption and functional activity on polyurethane biomaterial surfaces in the presence of other proteins. The amount of fibrinogen adsorbed on surfaces as recognized by an antifibrinogen polyclonal antibody when in competitive adsorption with human serum albumin (HSA) or human IgG was found to be related to the molar ratio of proteins. A significant decrease in fibrinogen adsorption was observed only when the fraction of smaller proteins reached a threshold value, dependent on smaller protein properties. The functional activity of fibrinogen was measured by a monoclonal antibody recognizing a region containing the dodecapeptide sequence located at the C-terminus of the γ-chain, γ-400-411. Results show that the presence of smaller proteins affected the conformational structure of fibrinogen and increased the availability of platelet binding sites in fibrinogen adsorbed on surfaces. Platelet adhesion was performed on polyurethane surfaces, which were competitively preadsorbed with fibrinogen and HSA. Platelet adhesion correlated well with the functional activity of fibrinogen, measured after competitive adsorption on surfaces. The work suggests that platelet adhesion is not necessarily determined by the amount of adsorbed fibrinogen but is related to the activity of fibrinogen as measured by the availability of the platelet binding sites in the fibrinogen, γ-chain dodecapeptide.

Phenylketonuria, a congenital metabolic defect, has been identified as a consequence of the formation of toxic l-phenylalanine fibrillar self-assembly under millimolar concentration in blood. Here, we have studied the influence of l-phenylalanine on the model lipid membrane like 1,2-diacyl-sn-glycero-phosphocholine and 1,2-dimyristoyl-sn-glycero-3-phosphocholine in the aqueous medium with millimolar concentration. The bilayers of the phospholipid vesicles are deformed after the interaction with phenylalanine, which is monitored through the fluorescence lifetime imaging microscopic study. The rigidity and shape of the phospholipid vesicles are recovered after the introduction of a short hydrocarbon chain containing imidazolium ionic liquid, 1-ethyl-3-methylimidazolium hexafluorophosphate ([C2mim]PF6). The long-chain imidazolium ionic liquid, 1-methyl-3-nonylimidazolium hexafluorophosphate (C9mim]PF6), further distorted, fused, and decreased the rigidity of the vesicle bilayer.

Bacterial motility is essential for navigating heterogeneous environments like soil, where it plays a key role in nutrient cycling, bioremediation, and overall soil health. Despite its importance, the interplay between bacterial motility and soil microstructures-such as the effects of physical confinement and interfacial interactions-remains underexplored. In this study, we investigated the motility of Escherichia coli bacteria in aqueous micro-environments with three different natural soil samples and examined how the particle size, void fraction, and proximity to soil particles affect bacterial motility and movement patterns by quantitatively analyzing bacterial trajectories, velocities, and directional changes. We observed that bacterial velocity decreased significantly in soil micro-environments, showing a strong positive correlation with the soil particle size and a negative correlation with the void fraction of the soil samples. Additionally, bacteria in soil micro-environments showed rapid and dramatic directional changes, and the rate of directional changes of bacteria was negatively correlated with the particle size. These results were further validated with synthetic micro-environments with glass microspheres. As the density of microspheres increased, the translational velocity of bacteria decreased while the directional changes increased. This study enhances our understanding of how the soil type, porosity, and particle proximity impact bacterial movement and is expected to contribute to a better understanding of bacterial activities on soil health and management.

Exosomes are one of the extracellular vesicles that are secreted by almost all cell types and body fluids. Because they are nanosized (30-200 nm), they can be used as natural nanovesicles. Exosomes have recently been preferred for their low immunogenicity and toxicity features for cell-free therapy, nano-drug carriers, and regenerative medicine. Rapid and appropriate exosome isolation has become increasingly critical due to its extensive application area. In this study, we isolated the MCF-7 cell exosomes using a biological membrane that works for nanoparticle isolation. Our results showed that the number of exosomes was 2 × 106 particles per ml in the cell line media, with a peak size of 110 nm. The proposed technique has features such as simplifying the operative procedures, low cost, and high efficiency. In addition, this technique did not use high-cost reactants, and it was not time-consuming. Additionally, no further procedure was necessary, and the amount of hand manipulation was minimal.

G-quadruplexes (G4) have been proposed as an alternative target for cancer therapy, as the folding of DNA sequences into stabilized G4 in the cancer microenvironment affects key biological functions. The antimalarial drugs, hydroxychloroquine (HCQ) and chloroquine (CQ), are in the clinical trial stage for cancer therapy and have been found to fold DNA sequences into the stabilized G4 even in the absence of KCl salt. In this study, the role of loop nucleobases in terms of chemical nature, number, and location in the HCQ-/CQ-induced folding of DNA sequences into G4 in the absence of KCl has been investigated systematically. The data indicate that both drugs selectively induce the folding of DNA sequences into G-quadruplexes (G4) that contain thymine loop nucleobases. The folding tendency of DNA sequences into stabilized G4 decreases with the increase in the thymine loop nucleobases. Moreover, DNA sequences with fewer thymine loop nucleobases tend to fold into stable G4 when the thymine residues are present at the terminal positions, whereas sequences with more thymine loop nucleobases show higher G4 folding propensity when these bases are located at the central loop. These findings are important in understanding the anticancer effect of antimalarial drugs.

Mechanical properties of the extracellular matrix (ECM) modulate cell-substrate interactions and influence cellular behaviors such as contractility, migration, and proliferation. Although the effects of substrate stiffness on mechanobiology have been well studied, the role of ECM viscoelasticity in fibrotic progression remains less understood. To examine how viscoelasticity affects the biophysical properties and regulates signaling of human mammary fibroblasts, we engineered elastic (E) and viscoelastic (VE) polyacrylamide hydrogels with comparable storage moduli (∼14.52 ± 1.03 kPa) but distinctly different loss moduli; mean loss moduli for VE gels was 36.9% higher at 0.05 Hz than E gels. Fibroblasts cultured on E hydrogels spread extensively (2428.93 ± 864.71 μm2), developed prominent stress fibers with higher zyxin intensity, and generated higher traction stresses (2931.57 ± 1732.61 Pa). In contrast, fibroblasts on VE substrates had 54.2% smaller focal adhesion areas, exhibited 51.8% lower critical adhesion strengths, and generated 21% lower traction stresses (p < 0.001). These substrates also promoted migration and showed enhanced proliferation with reduced Yes-associated protein (YAP) activity, suggesting a mechanotransduction shift that may involve alternative signaling pathways. In contrast, E substrates showed YAP nuclear translocation, consistent with greater cytoskeletal tension and contractility. These findings highlight the importance of energy dissipation mechanisms in regulating fibroblast function on substrates mimicking the fibrotic milieu. Our results demonstrate that tuning the ECM viscoelasticity is a useful strategy to regulate cell behaviors in tissue-engineered scaffolds and develop better disease modeling for regenerative medicine.

Syntheses of gold-manganese oxide nanocomposites were attempted by a redox-mediated growth method under varying mild reaction conditions with amino acid as a stabilization agent; finally, the nanocomposites were applied for superoxide dismutase (SOD)-mimic activity. Growth reaction was performed by the reduction of Au(III) with Mn(0) powder on the surface of citrate-stabilized gold nanoparticles as seeds. Variable reaction conditions were attempted to monitor the effect of the pH and, finally, optimized based on the critical properties of the nanocomposites including their long-term stability. In a neutral medium, tryptophan-stabilized Au-Mn3O4 nanocomposites were obtained. Stable Au-Mn2O3 nanocomposites were formed at basic pH in the presence of hydrophobic amino acids. The present work elucidates the role of amino acids, especially tryptophan, in stabilizing gold-manganese oxide nanocomposites. The effect of crystalline vs. the amorphous nature of Mn3O4 sheets in the tryptophan-stabilized nanocomposites was evaluated in SOD-mimetic applications. The IC50 values for the newly synthesized Au-Mn3O4 nanocomposites with crystalline or amorphous Mn3O4 sheets at room temperature were found to be 125 times and 25 times better with respect to the reported Mn3O4 nanoparticles synthesized after calcination at 600 °C. These results provide useful insights into the synthesis of gold-manganese oxide nanocomposites with tunable properties and their potential applications in the growing field of nanozymes.

Forces acting between an atomic force microscopy silicon nitride cantilever and the bacterial surface biopolymers of Escherichia coli or Pseudomonas putida were spatially probed in water. The interactions were fitted to a model of steric repulsion to estimate the bacterial surface biopolymer brush length and grafting density. The forces were further fitted to a Hertz model of contact mechanics modified by Sneddon et al. to quantify Young's modulus of elasticity for the cells. Contour plots of the quantified properties described above (i.e., the bacterial surface biopolymer brush length and grafting density, and Young's modulus of elasticity for the cells) based on the location coordinates on the bacterial surfaces were generated. Our contour plots indicated the bacterial cells organize their biopolymers uniquely to help them survive in the environment. Specifically, our results showed that the perimeter of a bacterial cell is characterized by a more flexible as well as longer biopolymer brush compared to those estimated at the center top of the cell. These results suggest that bacteria are likely to use their longer brushes on the edges to facilitate their adhesion by bridging surfaces. Also, they maintain their structural reinforcement by developing higher densities of grafted biopolymers and hence higher elasticities at their centers. Moreover, a stronger linear relationship was observed between the brush thicknesses and the grafting densities for the collapsed brush at the center of the cells when compared to the perimeter of the cells.