Low Hemolysis Rate Research Articles

Fucoidan/collagen composite coating on magnesium alloy for better corrosion resistance and pro-endothelialization potential

Magnesium alloy stents (MAS) have broad application prospects in the treatment of cardiovascular diseases. However, poor corrosion resistance and biocompatibility greatly limit the clinical application of MAS. In this work, the coating consisting of MgF2 layer, polydopamine layer, fucoidan and collagen IV was constructed on Mg-Zn-Y-Nd (ZE21B) alloy to improve its corrosion resistance and pro-endothelialization potential. The fucoidan and collagen IV in the coating could obviously enhance the hemocompatibility and pro-endothelialization potential respectively. Compared with bare ZE21B alloy, the fucoidan/collagen composite coating modified ZE21B alloy possessed lower corrosion current density and better corrosion resistance. Moreover, the modified ZE21B alloy exhibited relatively low hemolysis rate, fibrinogen adsorption and platelet adhesion in the blood experiments, suggesting the improved hemocompatibility. Furthermore, the modified ZE21B alloy favorably supported the adhesion and proliferation of vascular endothelial cells (ECs) and effectively regulated the phenotype of smooth muscle cells (SMCs), thus improving the pro-endothelialization potential of vascular stent materials. The fucoidan/collagen composite coating can significantly improve the corrosion resistance and pro-endothelialization potential of ZE21B alloy, showing great potential in the development of degradable MAS.

Comprehensive biosafety assessment of Ag-ZnO/talc nanomaterials: Implications for antibacterial applications

Given the global proliferation of pathogenic microorganisms, there exists a pressing imperative to cultivate efficacious nanomaterials possessing antimicrobial attributes, thereby impeding the transmission of infectious diseases. Clay-based nanoparticles, due to their inherent properties, serve as optimal candidates for the creation of innovative antimicrobial agents, particularly for coating materials. In this study, ZnO nanoparticles were synthesized on talc surfaces and doped with Ag+, yielding an effective antimicrobial composite (Ag-ZnO/talc). The primary aim was to comprehensively evaluate the antimicrobial effectiveness, material compatibility, and biosafety of Ag-ZnO/talc, as well as its potential applications in antibacterial coatings. The finding underscored the remarkable antibacterial properties of Ag-ZnO/talc composites, chiefly through the generation of reactive oxygen species, leading to impairment of the bacterial membrane and leakage of nucleic acid content. A biosafety evaluation indicated minimal cytotoxicity, a low hemolysis rate, and negligible skin tissue reactions, thereby suggesting its suitability for human application. Furthermore, the incorporation of the antimicrobial agent Ag-ZnO/talc did not significantly alter the physicochemical characteristics of the coating, while maintaining an enduring antimicrobial effect for a duration of two months. These findings establish the potential of clay-based antimicrobials for effective and safe application in coatings, facilitating the development of antimicrobial coatings in diverse industrial and public health environments.

Preparation, properties and in vitro osteogensis of self-reinforcing injectable hydrogel

As an attractive biomaterial for bone reconstruction, injectable biomaterials have many prominent characteristics such as good biocompatibility and bone-filling ability. However, there are weak as load-bearing scaffolds. In this study, polyvinyl alcohol (PVA) and bioactive glass (BAG) were interpenetrated into sodium alginate (SA) network to obtain self-enhanced injectable hydrogel. The optimum ratio of PVA/SA/BAG hydrogel was determined based on injectability, gelation time and chemical characterization. Results showed that the selected ratio had the shortest gelation time of 3.5min, and the hydrogel had a rough surface and good coagulation property. The hydrogel was capable of carrying 1kg of weight by mineralization for 14 d The compressive strength, compressive modulus, and fracture energy of the hydrogel reached 0.12MPa, 0.376MPa and 17.750kJ m−2, respectively. Meanwhile, the hydrogel had high moisture content and dissolution rate, and it was sensitive to temperature and ionic strength. Hydroxyapatite was generated on the hydrogel surface, and the hydrogel pores increased, and the pore size enlarged. The biocompatibility of PVA/SA/BAG hydrogel was analyzed using hemolysis and cytotoxicity assays. Results revealed its good biocompatibility with low hemolysis rate and no cytotoxicity to MC3T3-E1 cells. The hydrogel was also found to promote the differentiation of MC3T3-E1 cells with significantly increased in ALP activity and expression of relevant differentiation factors. In vitro mineralization assay showed an increase in calcium nodules and calcification area, indicating the ability of hydrogel to promote mineralization MC3T3-E1 cells. These findings indicated that PVA/SA/BAG hydrogel had potential uses in the field of irregular bone-defect repair due to its injectability, cytocompatibility, and tailorable functionality.

A threefold increase in SAR performance for magnetic hyperthermia by compositional tuning in zinc-substituted iron oxide superparamagnetic nanoparticles with superior biocompatibility

In this work, we report a ultrahigh specific absorption rate (SAR) performance in Zn-substituted magnetite superparamagnetic (SPM) nanoparticles (NPs) for potential application in magnetic hyperthermia (MHT)-based cancer treatment. Although MHT shows promise in cancer therapy, challenges such as low heating performance, agglomeration of magnetic nanoparticles (MNPs) in blood veins, cytotoxicity, and hemocompatibility have hindered clinical uses. To overcome these challenges, we adopted a reverse-micelles based coprecipitation synthesis approach to prevent MNPs agglomeration and optimized the substitution of Zn ions in magnetite to enhance heating performance. Calorimetric measurements showed SAR values of 118 W/g and 181 W/g for magnetite NPs using the initial slope method (ISM) and Box Lucas method (BLM), respectively. Through our compositional optimizations, we achieved a significant increase in SAR value by consciously substituting Zn2+ ions in the magnetite lattice. Specifically, we obtained SAR values of 325 W/g and 579 W/g (>300% increase) for Zn0.3Fe2.7O4 MNPs using ISM and BLM, respectively. This enhancement can be attributed to improved saturation magnetization (174–257 kA/m) and magneto-crystalline anisotropy (12–24 kJ/m3). The increase in saturation magnetization in the magnetite MNPs can be explained by the higher magnetic moment resulting from increased Zn concentration up to ZnxFe3-xO4(x = 0.3), strengthening the JAB interaction. However, further increases in Zn concentration lead to a decrease in saturation magnetization due to non-collinearity, as described by the Yafet-Kittle model. Our optimized MNPs exhibit improved heating performance, enabling the use of lower MNPs concentrations for cancer treatment, reducing potential toxicity effects. Biocompatibility investigations demonstrated a low hemolysis rate (<5%) in a hemolysis assay with red blood cells and high cytocompatibility (>92% cell viability) in MTT assays for all compositions, confirming their potential suitability for clinical applications. This study offers a promising approach to enhance SAR performance, addressing MHT-based cancer treatment challenges, and improving clinical suitability.

An improved blood hemorrhaging treatment using diatoms frustules, by alternating Ca and light levels in cultures

Hemorrhage control requires hemostatic materials that are both effective and biocompatible. Among these, diatom biosilica (DBs) could significantly improve hemorrhage control, but it induces hemolysis (the hemolysis rate > 5%). Thus, the purpose of this study was to explore the influence of Ca2+ biomineralization on DBs for developing fast hemostatic materials with a low hemolysis rate. Here, CaCl2 was added to the diatom medium under high light (cool white, fluorescent lamps, 67.5 µmol m−2 s−1), producing Ca-DBs-3 with a particle size of 40–50 μm and a Ca2+ content of Ca-DBs-3 obtained from the higher concentration CaCl2 group (6.7 mmol L−1) of 0.16%. The liquid absorption capacity of Ca-DBs-3 was 30.43 ± 0.57 times its dry weight; the in vitro clotting time was comparable to QuikClot® zeolite; the hemostatic time and blood loss using the rat tail amputation model were 36.40 ± 2.52 s and 0.39 ± 0.12 g, which were 40.72% and 19.50% of QuikClot® zeolite, respectively. Ca-DBs-3 showed no apparent toxicity to L929 cells (cell viability > 80%) and was non-hemolysis (the hemolysis rate < 2%). This study prepared Ca-DBs-3 with a rapid hemostatic effect and good biocompatibility, providing a path to develop diatom biosilica hemostatic materials.

The effect of addition of K2ZrF6 on the structures and properties of AZ31 magnesium alloy MAO coating

It is a challenge to improve the corrosion rate and blood compatibility of biomedical magnesium alloy implants in human body. Scanning electron microscope (SEM), energy dispersive spectrometer (EDS) and X-ray diffraction (XRD) were used to study the Properties of K2ZrF6 modified AZ31 magnesium alloy composite coating. The corrosion behavior of the sample in simulated body fluid (SBF) was evaluated by hydrogen evolution corrosion, potentiodynamic polarization cur ve and electrochemical impedance spectroscopy. The results show that the corrosion resistance of magnesium alloy is significantly improved by composite coating. The wettability test shows that K2ZrF6 greatly improves the biocompatibility of MAO coating on magnesium alloy. The hemolysis test shows that the composite coating makes magnesium alloy have low hemolysis rate. The increase of PH value and magnesium ion concentration in solution caused by corrosion of magnesium alloy can be adjusted by adding K2ZrF6. The corrosion resistance mechanism of MAO coating on K2ZrF6 modified magnesium alloy was discussed. In this experiment, the optimum amount of K2ZrF6 is 4 g/L.

Biofunctionalized Decellularized Tissue-Engineered Heart Valve with Mesoporous Silica Nanoparticles for Controlled Release of VEGF and RunX2-siRNA against Calcification.

The goal of tissue-engineered heart valves (TEHV) is to replace normal heart valves and overcome the shortcomings of heart valve replacement commonly used in clinical practice. However, calcification of TEHV is the major bottleneck to break for both clinical workers and researchers. Endothelialization of TEHV plays a crucial role in delaying valve calcification by reducing platelet adhesion and covering the calcified spots. In the present study, we loaded RunX2-siRNA and VEGF into mesoporous silica nanoparticles and investigated the properties of anti-calcification and endothelialization in vitro. Then, the mesoporous silica nanoparticle was immobilized on the decellularized porcine aortic valve (DPAV) by layer self-assembly and investigated the anti-calcification and endothelialization. Our results demonstrated that the mesoporous silica nanoparticles delivery vehicle demonstrated good biocompatibility, and a stable release of RunX2-siRNA and VEGF. The hybrid decellularized valve exhibited a low hemolysis rate and promoted endothelial cell proliferation and adhesion while silencing RunX2 gene expression in valve interstitial cells, and the hybrid decellularized valve showed good mechanical properties. Finally, the in vivo experiment showed that the mesoporous silica nanoparticles delivery vehicle could enhance the endothelialization of the hybrid valve. In summary, we constructed a delivery system based on mesoporous silica to biofunctionalized TEHV scaffold for endothelialization and anti-calcification.

Eco-friendly cellulose-based hydrogel functionalized by NIR-responsive multimodal antibacterial polymeric ionic liquid as platform for promoting wound healing

With the trend of sustainable development and the complex medical environment, there is a strong demand for multimodal antibacterial cellulose wound dressing (MACD) with photothermal therapy (PTT). Herein, a novel MACD fabrication strategy with PTT was proposed and implemented through graft polymerization of an imidazolium ionic liquid monomer containing iron complex anion structure. The fabricated hydrogels exhibited excellent antibacterial properties because of the efficient photothermal conversion ability (68.67 %) of ionic liquids and the intrinsic structural characteristic of quaternary ammonium salts. The antibacterial ratio of cellulosic hydrogel dressings to S. aureus and E. coli could reach 99.57 % and 99.16 %, respectively. Additionally, the fabricated hydrogels demonstrated extremely low hemolysis rates (<5 %) and excellent cell viability (~>85 %). Furthermore, in vivo antibacterial experimental results proved that the fabricated antibacterial dressings could significantly accelerate wound healing. Therefore, the proposed strategy would provide a new method of designing and preparing high-performance cellulose wound dressings.

A multi-crosslinking strategy of organic and inorganic compound bio-adhesive polysaccharide-based hydrogel for wound hemostasis

Polysaccharides are naturally occurring polymers with exceptional biodegradable and biocompatible qualities that are used as hemostatic agents. In this study, photoinduced CC bond network and dynamic bond network binding was used to give polysaccharide-based hydrogels the requisite mechanical strength and tissue adhesion. The designed hydrogel was composed of modified carboxymethyl chitosan (CMCS-MA) and oxidized dextran (OD), and introduced hydrogen bond network through tannic acid (TA) doping. Halloysite nanotubes (HNTs) were also added, and the effects of various doping amount on the performance of the hydrogel were examined, in order to enhance the hemostatic property of hydrogel. Experiments on vitro degradation and swelling demonstrated the strong structural stability of hydrogels. The hydrogel has improved tissue adhesion strength, with a maximum adhesion strength of 157.9 kPa, and demonstrated improved compressive strength, with a maximum compressive strength of 80.9 kPa. Meanwhile, the hydrogel had a low hemolysis rate and had no inhibition on cell proliferation. The created hydrogel exhibited a significant aggregation effect on platelets and a reduced blood clotting index (BCI). Importantly, the hydrogel can quickly adhere to seal the wound and has good hemostatic effect in vivo. Our work successfully prepared a polysaccharide-based bio-adhesive hydrogel dressing with stable structure, appropriate mechanical strength, and good hemostatic properties.

A bacteriostatic hemostatic dressing prepared from l-glutamine-modified chitosan, tannic acid-modified gelatin and oxidized dextran

In this study, porous hemostatic sponges (CGS1, CGS2 and CGS3) with proper absorption (38–43×) and air permeability (2214 g/m2·day) were prepared from l-glutamine-modified chitosan (CG), tannic acid-modified gelatin (GTA), and oxidized dextran (ODEX) by Schiff base crosslinking reaction. Among them, CGS2 was proved to have high porosity (88.98 %), durable water retention (>6 h), strong antibacterial activity, proper mechanical quality, and suitable tissue adhesion. In addition, CGS2 had good biocompatibility, mainly manifested in low hemolysis rate (<0.4 %), low cytotoxicity (relative cell activity>90 %), and good biodegradability in vitro. The hemostatic time and blood loss in CGS2 group were much lower than those in commercial gelatin sponge group in three animal injury models. Moreover, the activated partial thromboplastin time (APTT) and the prothrombin time (PT) results indicated that CGS2 promoted coagulation by activating the endogenous coagulation pathway. These results suggested that CGS2 had great potential for rapid hemostasis and avoidance of wound infection.

A Novel NQO1 Enzyme-Responsive Polyurethane Nanocarrier for Redox-Triggered Intracellular Drug Release.

The design of nano-drug delivery vehicles responsive to tumor microenvironment stimuli has become a crucial aspect in developing cancer therapy in recent years. Among them, the enzyme-responsive nano-drug delivery system is particularly effective, as it utilizes tumor-specific and highly expressed enzymes as precise targets, leading to increased drug release at the target sites, reduced nonspecific release, and improved efficacy while minimizing toxic side effects on normal tissues. NAD(P)H:quinone oxidoreductase 1 (NQO1) is an important reductase associated with cancer and is overexpressed in some cancer cells, particularly in lung and breast cancer. Thus, the design of nanocarriers with high selectivity and responsiveness to NQO1 is of great significance for tumor diagnosis and treatment. It has been reported that under physiological conditions, NQO1 can specifically reduce the trimethyl-locked benzoquinone structure through a two-electron reduction, resulting in rapid lactonization via an enzymatic reaction. Based on this, a novel reduction-sensitive polyurethane (PEG-PTU-PEG) block copolymer was designed and synthesized by copolymerizing diisocyanate, a reduction-sensitive monomer (TMBQ), and poly(ethylene glycol). The successful synthesis of monomers and polymers was verified by nuclear magnetic resonance (1H NMR) and gel permeation chromatography (GPC). Then, the PEG-PTU-PEG micelles were successfully prepared by self-assembly, and their reductive dissociation behavior in the presence of Na2S2O4 was verified by dynamic light scattering (DLS), 1H NMR, and GPC. Next, the model drug doxorubicin (DOX) was encapsulated into the hydrophobic core of this polyurethane micelles by microemulsion method. It was observed that the drug-loaded micelles could also achieve a redox response and rapidly release the encapsulated substances. In vitro cell experiments demonstrated that PEG-PTU-PEG micelles had good biocompatibility and a low hemolysis rate (<5%). Furthermore, in the presence of an NQO1 enzyme inhibitor (dicoumarol), lower drug release from micelles was observed in A549 and 4T1 cells by both fluorescence microscopy and flow cytometry assays, but not in NIH-3T3 control cells. Predictably, DOX-loaded micelles also showed lower cytotoxicity in 4T1 cells in the presence of NQO1 enzyme inhibitors. These results indicate that drug-loaded polyurethane micelles could accomplish specific drug release in the reducing environment in the presence of NQO1 enzymes. Therefore, this study provides a new option for the construction of polyurethane nanocarriers for precise targeting and reductive release, which could benefit the intracellular drug-specific release and precision therapy of tumors.

Amino-rich nanofiber membrane with favorable hemocompatibility for highly efficient removal of bilirubin from plasma

Bilirubin is a serious toxin in the blood of liver failure patients, and the development of bilirubin adsorbent with high removal efficiency, excellent hemocompatibility is crucial to improve the efficacy of hemoperfusion therapy. Herein, PAN/PEI nanofiber membrane (NFM) with amino-rich and smooth surface structure was prepared through a more facile co-blended electrospun method. During simulated adsorption experiments in vitro, PAN/PEI NFMs exhibited a high adsorption capacity of 142.79 mg g−1 for free bilirubin at clinical bilirubin concentration (100 mg L-1) in patients with liver failure. In addition, the bilirubin removal efficiency in static adsorption exceeded 96% when the PAN/PEI NFMs addition was greater than 120 mg. In particular, PAN/PEI NFMs displayed excellent hemocompatibility, presented a low hemolysis rate (0.4%), favorable anti-adhesion properties for hemocyte and plasma protein, and had no significant effect on coagulation. The development of this facile method promotes the feasibility of nanofibrous membranes for the treatment of hyperbilirubinemia with significant implications for improving therapeutic efficacy.

Research of Dynamic Corrosion Behavior, Microstructure, and Biocompatibility of Mg–Zn–Ca–Zr Alloys in Simulated Body Fluid Solution Induced by Zn Element Addition

Herein, the effect of Zn (2,3,4 and 5 wt%) addition on the microstructure, corrosion behavior, and biocompatibility of Mg‐xZn‐0.5Ca‐0.4Zr alloys is discussed by micromorphology, immersion/electrochemical, and cytotoxicity experiments. The results reveal that all as‐cast samples with a duplex morphology consist of Mg7Zn3 phase and α‐Mg matrix. With the addition of Zn element, the quantities of Mg7Zn3 phase increase gradually; while its micromorphology obviously changes from dot‐like to network shape, the average grain size decreases gradually. In addition, corrosion mechanism demonstrates that all as‐cast alloys suffer from microgalvanic corrosion between eutectic Mg7Zn3 and α‐Mg substrate due to potential difference of |ΔE| = 180 mV. However, the strip‐shape Mg7Zn3 contained in the Mg–4Zn–0.5Ca–0.4Zr alloy and compared with dot‐like\network shape phase can effectively hinder the spreading of corrosion from one grain to another, which causes Mg–4Zn–0.5Ca–0.4Zr to exhibit superior corrosion resistance. In addition, the biocompatibility conducted by methyl‐thiazolyl‐tetrazolium method via L929 cells reveals that as‐cast Mg–4Zn–0.5Ca–0.4Zr alloy is confirmed with low hemolysis rate (H% = 2.5%) and excellent proliferation capability (P% &gt; 100%), which suggest that Mg–4Zn–0.5Ca–0.4Zr may be a good candidate for implant application.

Metal-polyphenol polymer modified polydopamine for chemo-photothermal therapy.

Chemotherapy combined with photothermal therapy (PTT) is a new way to improve the curative effect of cancer treatment. Here, we developed a multifunctional nanoparticle, namely PTX@mPDA@Fe-GA with the loading of a chemotherapeutic drug paclitaxel (PTX) for targeted and synergistic chemotherapy/photothermal therapy in lung cancer. Fe-gallic acid (Fe-GA) was coated on the surface of mesoporous polydopamine (mPDA) nanoparticles, and then the PTX was placed in the mesopores. The drug release of the loaded PTX exhibited pH- and thermal-dual responsive manner. Both mPDA and Fe-GA have high photothermal conversion ability and play a role in photothermal therapy. In addition, the results revealed that mPDA@Fe-GA had excellent biocompatibility and low hemolysis rate. The PTX-loaded mPDA@Fe-GA not only has excellent killing effect on lung cancer cells (A549) in vitro, but also can significantly suppress the growth of A549 subcutaneous tumor in nude mice. In a nutshell, the developed multifunctional nanoparticles integrate photothermal therapy and efficient chemotherapeutic drug delivery, providing new therapeutic ideas in the fight against lung cancer.

A polysaccharide/chitin hydrogel wound dressing from a Periplanattica americana residue: coagulation, antioxidant activity, and wound healing properties

Pharmaceuticals derived from the raw materials of Periplanattica americana have been applied for wound healing, liver disease treatment, and antitumor therapy. However, the resulting residues of P. americana have not been well exploited. We found that P. americana residues comprised high amounts of chitin (PC) and polysaccharides (PAP) exhibit good biological activity. Compared to shrimp-derived chitin, PC has a smaller molecular weight (Mv), lower crystallinity, and looser molecular structure, demonstrating stronger antioxidant activity and degradability. After adding the PAP, the PC solution rapidly lost fluidity and formed a hydrogel (P/PCGEL) that had antioxidation, biodegradability, and injectability properties and exhibited rapid coagulation, good water absorption and retention, and a low hemolysis rate (HR). In vivo studies reported that the P/PCGEL reduced edema during burns, accelerated collagen synthesis and deposition, reduced reactive oxygen species (ROS) levels, and increased superoxide dismutase (SOD) levels, thereby reducing the inflammatory response, avoiding oxidative stress, and effectively promoting wound healing. Furthermore, the P/PCGEL demonstrated good biocompatibility, rapid biodegradation, and injectability, thereby reducing the risk of trauma and infection engendered by repeated wound opening and dressing changes. These properties also demonstrated the potential application for this hydrogel in preparing injectable hydrogel excipients. Hence, this study provided a hydrogel-formed wound dressing comprising pure natural ingredients and offering convenient administration, economic availability, and strong tissue repair ability.

Brigatinib-repurposed chemo-photodynamic therapy nanoplatform via effective apoptosis against colorectal cancer

Colorectal cancer (CRC), a malignancy with a relatively high fatality rate, still poses a growing global public health challenge due to the lack of well-established and effective treatment strategies. Brigatinib, an ALK inhibitor approved for the treatment of ALK-positive NSCLC, has been repurposed to suppress the growth of ALK-negative CRC cells via sustained endoplasmic reticulum (ER) stress. Moreover, the photosensitizer Chlorine e6 (Ce6) exhibits a high singlet oxygen quantum yield, which promote the generation of reactive oxygen species (ROS) to exacerbate ER stress and function synergistically with chemotherapeutics. However, the clinical application of both brigatinib and Ce6 is limited by their poor water solubility. Therefore, a repurposed chemo-photodynamic therapy nanoplatform (BCT NPs) utilizing d-α-tocopheryl polyethylene glycol 1000 succinate (TPGS) as a nanocarrier for the codelivery of the chemotherapeutics brigatinib and photosensitizer Ce6 is developed, which is capable of disrupting redox homeostasis and enhancing ER stress against CRC. The developed nanoplatform successfully addressed therapeutic drug solubility, improved brigatinib biocompatibility with a lower hemolysis rate, and demonstrated satisfactory CRC suppression effects in vitro and in vivo. Overall, BCT NPs provide a promising strategy to construct repurposed and versatile nanoplatforms against CRC.

Analysis of the toxicological and pharmacokinetic profile of Kaempferol-3-O-β-D-(6"-E-p-coumaryl) glucopyranoside - Tiliroside: in silico, in vitro and ex vivo assay.

Tiliroside is a glycosidic flavonoid present in many plants species including Helicteres velutina K. Schum (Malvaceae sensu lato), commonly known in Brazil as "pitó". This molecule has been shown to have many biological activities, however no study has been carried out to investigate the toxicity of this substance. The present work aimed to evaluate the possible cellular toxicity in silico, in vitro and ex-vivo of the kaempferol-3-O-β-D-(6"-E-p-coumaroyl) glucopyranoside (tiliroside), through chemical structure analysis, toxicity assessment and predictive bioactive properties, using human samples for in vitro and ex-vivo tests. The in silico analysis suggests that tiliroside exhibited great absorption index when penetrating biological membranes. In addition, it also displayed considerable potential for cellular protection against free radicals, and anticarcinogenic, antioxidant, antineoplastic, anti-inflammatory, anti-hemorrhagic and antithrombotic activities. The assessment of the hemolytic and genotoxic effects of tiliroside showed low hemolysis rates in red blood cells and absence of cellular toxicity in the oral mucosa cells. The data obtained indicate that this molecule could be a promising therapeutic approach as a possible new drug with biotechnological potential.

Bletilla striata polysaccharide – waterborne polyurethane hydrogel as a wound dressing

Polysaccharides are widely used in biomedicine because of their unique biological activity, low costs, and easy-to-obtain. In this paper, Bletilla striata polysaccharide (BSP) was integrated into waterborne polyurethane (WPU) to prepare a series of WPU-BSP (WPUB) hydrogels. The hydrogels showed good compressive strength, water absorption and retention ability, which are favorable for wound healing. Among them, the WPUB4 gel has the best comprehensive performances, including a compressive strength of 1.07 MPa, a swelling rate of 16.3, a reasonable WVRT of 2013 g/m2/day, and a long water retention time. About the in vitro biocompatibility, moreover, the WPUB4 hydrogel has a low hemolysis rate of 2.47%, a hydroxyl radical clearance rate of 35.5%, and little cytotoxicity with cell viability of 101.4%. Most importantly, the WPUB hydrogel dressings showed excellent ability in promoting wound healing. Compared to the conventional gauze, the wound surface area of mice treated with WPUB hydrogel was significantly reduced on day 3 after surgery and the wounds were healed on day 7. The new skin had a thicker epidermis and more capillaries. The WPUB hydrogels integrating BSP are promising to function as wound dressings.

Chitosan/Sodium Alginate/Velvet Antler Blood Peptides Hydrogel Promotes Diabetic Wound Healing via Regulating Angiogenesis, Inflammatory Response and Skin Flora.

BackgroundDiabetic ulcer remains a clinical challenge due to impaired angiogenesis and persistent inflammation, requiring new alternative therapies to promote tissue regeneration.PurposeIn this study, chitosan/sodium alginate/velvet antler blood peptides (CS/SA/VBPs) hydrogel (CAVBPH) was fabricated and used in the treatment of skin wounds in type 2 diabetes mellitus (T2D) for the first time.MethodsVBPs were prepared by hydrolysis and ultrafiltration, and their sequences were identified using LC-MS/MS. The CAVBPH was further fabricated and characterized. A mouse model of T2D was induced by a high-sugar and high-fat diet (HSFD) and streptozotocin (STZ) injection. CAVBPH was applied topically to T2D wounds, and its effects on skin repair and potential biological mechanisms were analyzed by appearance observation, histopathological staining, bioinformatics analysis, Western blot, and 16S rRNA sequencing.ResultsVBPs had numerous short-chain active peptides, excellent antioxidant activity, and a low hemolysis rate. CAVBPH exhibited desirable biochemical properties and participated in the diabetic wound healing process by promoting cell proliferation (PCNA and α-SMA) and angiogenesis (capillaries and CD31) and alleviating inflammation (CD68). Mechanistically, the therapeutic effect of CAVBPH on chronic wounds might rely on activating the PI3K/AKT/mTOR/HIF-1α/VEGFA pathway and reversing the expression of inflammatory cytokines TNF-α and IL-1β. The results of 16S rRNA sequencing indicated that T2D significantly altered the diversity and structure of skin flora at the wound site. CAVBPH treatment elevated the relative abundance of beneficial microbes (e.g., Corynebacterium_1 and Lactobacillus) and reversed the structural imbalance of skin microbiota.ConclusionThese results indicate that CAVBPH is a promising wound dressing, and its repair effect on diabetic wounds by regulating angiogenesis, inflammatory response, and skin flora may depend on the rich small peptides in VBPs.

Quaternized chitosan/cellulose composites as enhanced hemostatic and antibacterial sponges for wound healing

It is essential to enhance our antibacterial arsenal in the first-aid hemostatic treatment due to the healing delay and even death from the bacteria-contaminated wounds. Herein, serial quaternized chitosan with varying degrees of substitution (QCSX) was prepared by glycidyl trimethyl ammonium chloride modification. Then the obtained QCSX was conjugated with dialdehyde cellulose (DAC) through Schiff base reaction to obtain the corresponding composite sponges (2QCSX-DAC). The surface morphology, chemical structures, and physical characters of mechanical measurement, water uptake behavior, porosity, and degradation tests were determined. Furthermore, in vitro and in vivo biological assays were performed. The obtained 2QCSX-DAC sponges exhibit abundant porous structures, moderate mechanical properties, excellent water uptake performance, and effective bactericidal rates against Staphylococcus aureus and Escherichia coli. Moreover, these porous composite sponges have superior blood coagulation abilities with the blood coagulation time reduced by 76.6% and 59.8% compared with blank control and Celox™ as well as low hemolysis rates (<5%). Meanwhile, 2QCS3-DAC had benign cytotoxicity of L929 cells in vitro and could accelerate the infected wound healing of rats at the early stage in vivo. Overall, this composite sponge appears to be a viable wound dressing for daily wound care in civilian hospitals and emergency hemostasis on battlefields.