Biodegradable Electrospun Nonwovens Releasing Propolis as a Promising Dressing Material for Burn Wound Treatment

Biotransformation and metabolite activity analysis of flavonoids from propolis in vivo

Propolis is a natural resinous compound produced by bees, mixed with their saliva and wax, and has a range of biological benefits, including antioxidant and anti-inflammatory effects. This article reviews the in vivo transformation of propolis flavonoids and their potential influence on drug efficacy. Despite propolis is widely used, there is little research on how the active ingredients of propolis change in the body and how they interact with drugs. Future research will focus on these interactions and the metabolic fate of propolis in vivo.

Sodium alginate-based nanofibers loaded with Capparis Sepiaria plant extract for wound healing

Burn wounds are associated with infections, drug resistance, allergic reactions, odour, bleeding, excess exudates, and scars, requiring prolonged hospital stay. It is crucial to develop wound dressings that can effectively combat allergic reactions and drug resistance, inhibit infections, and absorb excess exudates to accelerate wound healing. To overcome the above-mentioned problems associated with burn wounds, SA/PVA/PLGA/Capparis sepiaria and SA/PVA/Capparis sepiaria nanofibers incorporated with Capparis sepiaria plant extract were prepared using an electrospinning technique. Fourier-transform infrared spectroscopy confirmed the successful incorporation of the extract into the nanofibers without any interaction between the extract and the polymers. The nanofibers displayed porous morphology and a rough surface suitable for cellular adhesion and proliferation. SA/PVA/PLGA/Capparis sepiaria and SA/PVA/Capparis sepiaria nanofibers demonstrated significant antibacterial effects against wound infection-associated bacterial strains: Pseudomonas aeruginosa, Enterococcus faecalis, Mycobaterium smegmatis, Escherichia coli, Enterobacter cloacae, Proteus vulgaris, and Staphylococcus aureus. Cytocompatibility studies using HaCaT cells revealed the non-toxicity of the nanofibers. SA/PVA/PLGA/Capparis sepiaria and SA/PVA/Capparis sepiaria nanofibers exhibited hemostatic properties, resulting from the synergistic effect of the plant extract and polymers. The in vitro scratch wound healing assay showed that the SA/PVA/Capparis sepiaria nanofiber wound-healing capability is more than the plant extract and a commercially available wound dressing. The wound-healing potential of SA/PVA/Capparis sepiaria nanofiber is attributed to the synergistic effect of the phytochemicals present in the extract, their porosity, and the ECM-mimicking structure of the nanofibers. The findings suggest that the electrospun nanofibers loaded with Capparis sepiaria extract are promising wound dressings that should be explored for burn wounds.

Recent Progress of Electrospun Nanofiber Dressing in the Promotion of Wound Healing

The nanofiber materials of three-dimensional spatial structure synthesized by electrospun have the characteristics of high porosity, high specific surface area, and high similarity to the natural extracellular matrix (ECM) of the human body. These are beneficial for absorbing wound exudate, effectively blocking the invasion of external bacteria, and promoting cell respiration and proliferation, which provides an ideal microenvironment for wound healing. Moreover, electrospun nanofiber dressings can flexibly load drugs according to the condition of the wound, further promoting wound healing. Recently, electrospun nanofiber materials have shown promising application prospects as medical dressings in clinical. Based on current research, this article reviewed the development history of wound dressings and the principles of electrospun technology. Subsequently, based on the types of base material, polymer-based electrospun nanofiber dressing and electrospun nanofiber dressing containing drug-releasing factors were discussed. Furthermore, the application of electrospun nanofiber dressing on skin tissue is highlighted. This review aims to provide a detailed overview of the current research on electrospun nanomaterials for wound healing, addressing challenges and suggesting future research directions to advance the field of electrospun dressings in wound healing.

Electrospinning-netting of spider-inspired polycaprolactone/collagen nanofiber-nets incorporated with Propolis extract for enhanced wound healing applications

Nanofibers hold significant promise for wound healing applications, but their potential is limited by their large diameter. To overcome this limitation, the development of nanofibrous systems with refined nanonets (approximately 20 nm in diameter) represents a notable improvement. In this study, a composite of polycaprolactone/collagen (PCLC) nano-fiber/nets (NFNs) was fabricated using benign solvents (acetic acid and formic acid) via the electro-spinning/netting (ESN) technique, harnessing the regenerative potential of collagen as a biological macromolecule. Additionally, to enhance the natural attributes of the NFNs structure, Propolis extract, renowned for its wound healing properties, was incorporated. Five ESN solutions were prepared: PCL, PCLC, PCLC/Pro 5 %, PCLC/Pro 10 %, and PCLC/Pro 15 %. NaCl salt was introduced into all ESN solutions to improve nanonets formation. FE-SEM imaging demonstrated successful nano-net formation in all ESN solutions except for the PCL formulation. The fabricated scaffolds exhibited spider-like nanonets with the addition of collagen and further enhanced nano-net formation with Propolis incorporation. Trunk nanofibers showed filamentous structures without any beads, with an average diameter of 164-728 nm, while the diameter of branched fibers (nanonets) was approximately 20 nm. WVTR values of the NFNs were comparable to commercial dressings such as Tegaderm. The results also demonstrated the potent cytoprotective effects of Propolis-loaded NFNs in a dose-dependent manner. Furthermore, the viability of HFF-2 cells after 72 h of culture on PCLC NFNs significantly increased compared to PCL nanofibers. The highest cell viability was observed in PCLC/Pro 15 % nanofibers after 24, 48, and 72 h of cell culture, indicating the proliferative effect of Propolis extract in nanoformulated form. Additionally, the scaffolds exhibited a hemocompatibility of <3 %, further highlighting their potential in wound healing therapeutics.

Propolis-Loaded Poly(lactic-co-glycolic Acid) Nanofibers: An In Vitro Study

Nanofibers have high potential through their high porosity, small pore sizes, lightweight materials, and their ability to mimic the extracellular matrix structure for use in the manufacture of wound dressings for wound treatment. In this study, poly(lactic-co-glycolic acid) (PLGA) nanofibers were produced by electrospinning. Propolis was loaded into the PLGA nanofibers by the dropping method. The average diameters and effects of propolis loading on the morphology of 37.5, 50, and 100% propolis-loaded PLGA nanofibers (PLGA-P37.5, PLGA-P50, and PLGA-P100) were evaluated by scanning electron microscopy (SEM). The successful loading of propolis into PLGA nanofibers was confirmed with Fourier transform infrared spectroscopy (FTIR) analysis. In vitro propolis release was examined at physiological pH. The antioxidant activity of propolis-loaded nanofibers was studied with 2,2-diphenyl-1-picrylhydrazyl (DPPH). Antimicrobial activities of the nanofibers against Escherichia coli, Staphylococcus aureus and Candida albicans strains were determined by the disk diffusion method. Consequently, PLGA-P50 and PLGA-P100 showed high antimicrobial activity on S. aureus and C. albicans. Cell viability was tested by 3-[4,5-dimethylthiazole-2-yl]-2,5-diphenyltetrazolium bromide (MTT) assay, and propolis-loaded PLGA nanofibers were found to be biocompatible with human fibroblast cells. In the wound scratch assay, propolis-loaded nanofibers supported wound closure with cell migration and proliferation. Thus, in vitro wound closure properties of propolis-loaded PLGA nanofibers were evaluated for the first time in the literature.

Therapeutic potential of propolis in alleviating inflammatory response and promoting wound healing in skin burn

Burns can cause inflammation and delayed healing, necessitating alternative therapies due to the limitations of conventional treatments. Propolis, a natural bee-produced substance, has shown promise in facilitating burn healing. This literature review provides a comprehensive overview of propolis' mechanisms of action, wound-healing properties, and its application in treating skin burns. Propolis contains bioactive compounds with antimicrobial, antioxidant, and anti-inflammatory properties, making it a promising candidate for managing skin burn injuries. It helps prevent infections, neutralize harmful free radicals, and promote a well-balanced inflammatory response. Moreover, propolis aids in wound closure, tissue regeneration, collagen synthesis, cellular proliferation, and angiogenesis, contributing to tissue regeneration and remodeling. The article discusses various propolis extracts, extraction methods, chemical composition, and optimized formulations like ointments and creams for burn wound treatment. Considerations regarding dosage and safety are addressed. Further research is needed to fully understand propolis' mechanisms, determine optimal formulations, and establish suitable clinical dosages. Nevertheless, propolis' natural origin and demonstrated benefits make it a compelling avenue for burn care exploration, potentially complementing existing therapies and improving burn management outcomes.

Propolis-loaded nanofiber scaffolds based on polyvinyl alcohol and polycaprolactone

Propolis-loaded electrospun nanofibers (PENs) have been regarded as promising candidates for biomedical purposes such as wound healing/dressing owing to their outstanding pharmacological and biological properties. This paper focuses on the development of electrospun nanofibers with optimum levels of propolis (PRP) and two polymer types (polycaprolactone (PCL) and polyvinyl alcohol (PVA)). Hence, response surface methodology (RSM) was employed to investigate the variation of the scaffold characteristics including porosity, average diameter, wettability, release, and tensile strength. For each response, a second-order polynomial model with a high coefficient of determination (R²) values ranging from 0.95 to 0.989 was developed using multiple linear regression analysis. The overall optimum region with the best characteristics was found to be at PCL/6% PRP and PVA/5% PRP. After selecting the optimal samples, the cytotoxicity assay showed no toxicity for the optimal concentrations of PRP. Furthermore, Fourier transform infrared (FTIR) spectra revealed that no new chemical functional groups were introduced in the PENs. Uniform fibers were found in the optimum samples without the appearance of a bead-like structure in the fibers. In conclusion, nanofibers containing the optimal concentration of PRP with suitable properties can be used in biomedical and tissue engineering.

Production and Anti-Inflammatory Performance of PVA Hydrogels Loaded with Curcumin Encapsulated in Octenyl Succinic Anhydride Modified Schizophyllan as Wound Dressings

Amphiphilic polysaccharides can be used as wall materials and applied to encapsulate hydrophobic active chemicals; moreover, there is significant demand for novel medical high-molecular-weight materials with various functions. In order to prepare amphiphilic schizophyllan (SPG), octenyl succinic anhydride (OSA) was chosen to synthesize OSA-modified schizophyllan (OSSPG) using an esterified reaction. The modification of OSSPG was demonstrated through FT-IR and thermal analysis. Moreover, it was found that OSSPG has a better capacity for loading curcumin, and the loading amount was 20 μg/mg, which was 2.6 times higher than that of SPG. In addition, a hydrogel made up of PVA, borax, and C-OSSPG (OSSPG loaded with curcumin) was prepared by means of the one-pot method, based on the biological effects of curcumin and the immune-activating properties of SPG. The mechanical properties and biological activity of the hydrogel were investigated. The experimental results show that the dynamic cross-linking of PVA and borax provided the C-OSSPG/BP hydrogel dressing with exceptional self-healing properties, and it was discovered that the C-OSSPG content increased the hydrogel's swelling and moisturizing properties. In fibroblast cell tests, the cells treated with hydrogel had survival rates of 80% or above. Furthermore, a hydrogel containing C-OSSPG could effectively promote cell migration. Due to the excellent anti-inflammatory properties of curcumin, the hydrogel also significantly reduces the generation of inflammatory factors, such as TNF-α and IL-6, and thus has a potential application as a wound dressing medicinal material.

Bilayer nanofibrous wound dressing prepared by electrospinning containing gallic acid and quercetin with improved biocompatibility, antibacterial, and antioxidant effects

OBJECTEIVES

The purpose of this study was to prepare an antibacterial, antioxidant, and biocompatible bilayer nanofibrous wound dressing by using electrospinning.

METHODS

The micromorphology and bilayer structure characteristics of the GA-Qe-PVP-PCL nanofibers were analyzed by SEM. The physicochemical characteristics were analyzed by XRD and FTIR. The uptake, mechanical properties, water contact angle, water vapor transmission and in vitro drug release were evaluated. In addition, the effect of antibacterial, antioxidant and biocompatability of the nanofibers were evaluated, respectively.

RESULTS

The SEM results showed that the GA-Qe-PVP-PCL nanofibers had a smooth surface, no beading phenomenon, and a prominent bilayer structure. The diameter and porosity of the drug-loading layer and waterproof support layer of the nanofibers were 842 ± 302 nm, 242 ± 50 nm, and 88.56 ± 1.67%, 94.49 ± 1.57%, respectively. Moreover, the water uptake, mechanical properties, water contact angle, and water vapor transmission showed ideal performance. The results of in vitro drug release indicated that GA and Qe were both released rapidly, which was conducive to accelerating wound healing. The GA-Qe-PVP-PCL nanofibers exhibited antibacterial effects against both bacteria as well as high antioxidant activity. Additionally, the GA-Qe-PVP-PCL nanofibers possessed good compatibility, could promote the proliferation, adhesion, and migration of L929 fibroblast cells.

CONCLUSION

The nanofibers we developed met the requirements of ideal materials for wound dressing, which makes the nanofibers the potential to be a wound dressing for wound care.

Nanostructured Electrospun Polycaprolactone-Propolis Mats Composed of Different Morphologies for Potential Use in Wound Healing

This study aimed to investigate different types of morphologies obtained using the electrospinning process to produce a material that enables wound healing while performing a controlled release. Using benign solvents, the authors prepared and characterised electrospun polycaprolactone mats loaded with propolis, a popular extract in traditional medicine with potential for skin repair. Different morphologies were obtained from distinct storage periods of the solution before electrospinning to investigate the effect of PCL hydrolysis (average diameters of fibres and beads: 159.2-280.5 nm and 1.9-5.6 μm, respectively). Phytochemical and FTIR analyses of the extract confirmed propolis composition. GPC and viscosity analyses showed a decrease in polymer molecular weight over the storage period (about a 70% reduction over 14 days) and confirmed that it was responsible for the nanostructure diversity. Moreover, propolis acted as a lubricant agent, affecting the spun solutions' viscosity and the thermal properties and hydrophilicity of the mats. All samples were within the value range of the water vapour transpiration rate of the commercial products (1263.08 to 2179.84 g/m²·day). Even though the presence of beads did not affect the propolis release pattern, an in vitro wound-healing assay showed that propolis-loaded mats composed of beaded fibres increased the cell migration process. Thus, these films could present the potential for use in wound dressing applications.

Research Progress on Therapeutic Effect and Mechanism of Propolis on Wound Healing

Propolis is a kind of reduct collected by bees from various plant sources. Because propolis is a mixture, it has a variety of biological activities, excellent anti-inflammatory and bactericidal effects. Especially in the treatment of infectious wounds, acute wounds, burns, and scalds and promoting wound healing, more and more scientists began to apply it to the research field of wound healing. The standard preparation of propolis combined with other compound components has a safer and less toxic effect in the treatment of trauma. In order to more effectively use propolis products in wound treatment. This paper reviews the effect and treatment mechanism of propolis on different types of wound healing, as well as the synergistic effect of propolis and other compounds, in order to provide ideas for the further exploration of the biological activity and pharmacological function of propolis in the future, as well as its in-depth development in the field of wound healing. It will also provide a theoretical reference for the further development and utilization of propolis.

Nonwoven Releasing Propolis as a Potential New Wound Healing Method-A Review

Wound healing poses a serious therapeutic problem. Methods which accelerate tissue regeneration and minimize or eliminate complications are constantly being sought. This paper is aimed at evaluation of the potential use of biodegradable polymer nonwovens releasing propolis as wound healing dressings, based on the literature data. Propolis is honeybee product with antioxidant, antibacterial, antifungal, anticancer, anti-inflammatory, analgesic, and regenerative properties. Controlled release of this substance throughout the healing should promote healing process, reduce the risk of wound infection, and improve aesthetic effect. The use of biodegradable aliphatic polyesters and polyester carbonates as a propolis carrier eliminates the problem of local drug administration and dressing changes. Well-known degradation processes and kinetics of the active substance release allows the selection of the material composition appropriate to the therapy. The electrospinning method allows the production of nonwovens that protect the wound against mechanical damage. Moreover, this processing technique enables adjusting product properties by modifying the production parameters. It can be concluded that biodegradable polymer dressings, releasing a propolis, may find potential application in the treatment of complicated wounds, as they may increase the effectiveness of treatment, as well as improve the patient’s life quality.

Green Approach to Develop Bee Pollen-Loaded Alginate Based Nanofibrous Mat

Green electrospun materials are gaining popularity in the quest for a more sustainable environment for human life. Bee pollen (BP) is a valuable apitherapeutic product and has many beneficial features such as antioxidant and antibacterial properties. Alginate is a natural and low-cost polymer. Both natural materials show good compatibility with human tissues for biomedical applications and have no toxic effect on the environment. In this study, bee pollen-loaded sodium alginate and polyvinyl alcohol (SA/PVA) nanofibrous mats were fabricated by the electrospinning technique. The green electrospun nanofibrous mats were analyzed by scanning electron microscopy (SEM), Fourier transforms infrared spectroscopy (FTIR), and differential scanning calorimeter (DSC). According to the findings of the study, the toxin-free electrospinning method is suitable for producing green nanomaterial. Because of the useful properties of the bee pollen and the favorable biocompatibility of the alginate fibers, the bee pollen-loaded SA/PVA electrospun mats have the potential for use in a variety of biomedical applications.

Electrospun paclitaxel delivery system based on PGCL/PLGA in local therapy combined with brachytherapy

The local administration of different drugs in anticancer therapy continue to attract attention. Thus, the idea of local delivery of cytostatics from nonwoven-structured polyesters seems to be highly desirable. It could reduce systemic drug levels and provide high local concentration of the chemotherapeutics at the tumor site and contribute to enhance the efficiency of the anticancer therapy. Poly(glycolide-ɛ-caprolactone) (PGCL) and poly(D,L-lactide-co-glycolide) (PLGA) synthesized with zirconium-based initiator have been used to prepare electrospun, drug-eluting patches since they possess very good fiber-forming ability. Well-known chemotherapeutic drug-paclitaxel has been loaded into fibrous structure as a model anticancer agent in order to obtain drug delivery systems for local administration. The drug dose in obtained nonwovens might be regulated by the thickness and total area of the implanted patches. Electrospinning of PGCL/PLGA blend allowed to obtain soft and flexible implantable materials. Flexibility has been important factor since it ensures convenient use when covering a tumor or filling a resection cavity. The effectiveness of designed nonwovens presented in the study has been tested in vivo on mouse model of breast cancer. The growth of the tumors was slowed down during in vivo study in comparison with drug-free nonwovens- The volume of the tumor was 40% lower. Drug-loaded electrospun systems implanted locally to the tumor site was further combined with brachytherapy which improved the effectiveness of the therapy in about 18%. Detailed analysis of the nonwovens before and during degradation process has been performed by means of Scanning Electron Microscopy, Differential Scanning Calorimetry, Nuclear Magnetic Resonance, Gel Permeation Chromatography, X-ray Diffraction. The molar mass changes of the nonwoven were quite rapid contrary to changes of comonomer unit content, thermal properties and morphology of the fiber.

Bee Venom in Wound Healing

Bee venom (BV), also known as api-toxin, is widely used in the treatment of different inflammatory diseases such as rheumatoid arthritis or multiple sclerosis. It is also known that BV can improve the wound healing process. BV plays a crucial role in the modulation of the different phases of wound repair. It possesses anti-inflammatory, antioxidant, antifungal, antiviral, antimicrobial and analgesic properties, all of which have a positive impact on the wound healing process. The mentioned process consists of four phases, i.e., hemostasis, inflammation, proliferation and remodeling. The impaired wound healing process constitutes a significant problem especially in diabetic patients, due to hypoxia state. It had been found that BV accelerated the wound healing in diabetic patients as well as in laboratory animals by impairing the caspase-3, caspase-8 and caspase-9 activity. Moreover, the activity of BV in wound healing is associated with regulating the expression of transforming growth factor (TGF-β1), vascular endothelial growth factor and increased collagen type I. BV stimulates the proliferation and migration of human epidermal keratinocytes and fibroblasts. In combination with polyvinyl alcohol and chitosan, BV significantly accelerates the wound healing process, increasing the hydroxyproline and glutathione and lowering the IL-6 level in wound tissues. The effect of BV on the wounds has been proved by numerous studies, which revealed that BV in the wound healing process brings about a curative effect and could be applied as a new potential treatment for wound repair. However, therapy with bee venom may induce allergic reactions, so it is necessary to assess the existence of the patient’s hypersensitivity to apitoxin before treatment.