Increased Fibroblast Metabolic Activity of Collagen Scaffolds via the Addition of Propolis Nanoparticles

A Combination of Anatolian Propolis and Curcumin Protects Fibroblasts Against Beclomethasone (Nazal Steroid)-Induced Oxidative Stress by Modulating IL-25, MMP-2, VEGF, and FGF-2 Expressions

Background: Nasal steroids are commonly prescribed in ear, nose, and throat clinics. It is observed that the use of nasal steroids is increasing due to the prevalence of allergic rhinitis. Because beclomethasone (BCM) toxicity is low, it is highly preferred in allergic rhinitis. The rate of toxicity increases with the increase in the duration and dose of BCM use. However, the protective mechanism of Anatolian propolis (AP) and curcumin (Cur) against BCM toxicity has not been fully explained. Aim: The study evaluates the potential BCM-induced toxicity effect on VEGF, MMP-2, IL-25, and IL-10 parameters after Cur and AP treatment. Materials and Methods: Cell viability, oxidative stress, and gene expression were used for toxicity evaluation. Results: AP 2.5 mg/mL and Cur 16 µg/mL show high viability and antioxidant capacity. BCM increased the levels of IL-25, IL-10, and MMP-2, and a decrease was detected in the expression levels of FGF-2 and VEGF. Conclusions: AP and Cur show effective healing, and AP has been shown to improve inflammation more effectively than Cur. However, the combination of AP and Cur significantly improved the induced toxicity effects.

An Advanced Combinatorial System from Vitis vinifera Leaves and Propolis Enhances Antioxidants' Skin Delivery and Fibroblasts Functionality

Background/Objectives: Vine leaves are a bulky by-product that are disposed of and treated as waste in the wine production process. In the present study polyphenols from vine leaves were extracted and simultaneously encapsulated in a new delivery system consisting of liposomes and cyclodextrins. This system was further combined with propolis polyphenols encapsulated in cyclodextrins, resulting in a colloidal suspension for the release of antioxidants in a time-controlled way, the rate of which depends on the ratio of the materials. The result is a raw material that exhibits antioxidant and ECM protective effects when administered in skin fibroblasts (NHDFs). Methods: The antioxidant and ECM promoting efficacy of the produced raw material was assessed by the Folin-Ciocalteu method, DPPH assay, and in cellulo assays in fibroblasts, such as the cell viability assay, scratch assay, cell migration assay, gene expression analysis, and immunofluorescence analysis, for the detection, visualization, and quantification of collagen-I, collagen-IIIa, and elastin signals and collagenase assay. Results: Treatment of NHDFs with the combinatorial delivery system promoted collagen and elastin synthesis and deposition in normal conditions and, upon induced external stress, as assessed by in vitro transcriptomic and proteomic analysis. A significant inhibition of collagenase was also observed, suggesting a multitargeted efficacy of the active ingredients also by preventing collagen degradation. Conclusions: Therefore, this liposome-cyclodextrin encapsulated polyphenol complex represents a novel bioactive ingredient with promising skin applications.

The effect of caffeic acid on tendon healing in rats with an Achilles tendon injury model

OBJECTIVES

This study aims to examine the effect of caffeic acid on tendon healing histopathologically and biomechanically in rats with an Achilles tendon injury model.

MATERIALS AND METHODS

Twenty male Wistar-albino rats were used in this study. The rats were divided into two groups as the experimental group and control group. All rats underwent a bilateral achillotomy injury model and then surgical repair. Postoperatively, for four weeks, the experimental group was given intraperitoneal caffeic acid (100 mg/kg/day suspended in saline), while the control group was given only intraperitoneal saline. At the end of four weeks, after sacrificing each rat, right Achilles tendons were subjected to biomechanical analysis and the Achilles tendons were subjected to histopathological analysis. Bonar and Movin scores were used for histopathological analysis. In biomechanical analysis, tensile test was applied to Achilles tendons until rupture. For each tendon, failure load, displacement, cross-sectional area, maximum energy, total energy, length, stiffness, ultimate stress and strain parameters were recorded.

RESULTS

According to Bonar and Movin scoring, the experimental group had lower scoring values than the control group (p=0.002 and p=0.002, respectively). Bonar scoring parameters were analyzed separately. Vascularity, collagen, and ground substance scores were lower in the experimental group compared to the control group (p=0.001, p=0.003, and p=0.047, respectively). No significant difference was found for tenocyte (p=0.064). In biomechanical analysis, failure load, displacement, ultimate stress, strain, and stiffness values were found to be higher in the experimental group compared to the control group (p=0.049, p=0.005, p=0.028, p=0.021, and p=0.049, respectively).

CONCLUSION

The caffeic acid contributed positively to tendon healing histopathologically and biomechanically in rats with an Achilles tendon injury model.

Effects of Propolis Impregnation on Polylactic Acid (PLA) Scaffolds Loaded with Wollastonite Particles against Staphylococcus aureus, Staphylococcus epidermidis, and Their Coculture for Potential Medical Devices

Several diseases and injuries cause irreversible damage to bone tissues, which may require partial or total regeneration or replacement. Tissue engineering suggests developing substitutes that may contribute to the repair or regeneration process by using three-dimensional lattices (scaffolds) to create functional bone tissues. Herein, scaffolds comprising polylactic acid and wollastonite particles enriched with propolis extracts from the Arauca region of Colombia were developed as gyroid triply periodic minimal surfaces using fused deposition modeling. The propolis extracts exhibited antibacterial activity against Staphylococcus aureus (ATCC 25175) and Staphylococcus epidermidis (ATCC 12228), which cause osteomyelitis. The scaffolds were characterized using scanning electron microscopy, Fourier-transform infrared spectroscopy, differential scanning calorimetry, contact angle, swelling, and degradation. Their mechanical properties were assessed using static and dynamic tests. Cell viability/proliferation assay was conducted using hDP-MSC cultures, while their bactericidal properties against monospecies cultures (S. aureus and S. epidermidis) and cocultures were evaluated. The wollastonite particles did not affect the physical, mechanical, or thermal properties of the scaffolds. The contact angle results showed that there were no substantial differences in the hydrophobicity between scaffolds with and without particles. Scaffolds containing wollastonite particles suffered less degradation than those produced using PLA alone. A representative result of the cyclic tests at F_max = 450 N showed that the maximum strain reached after 8000 cycles is well below the yield strain (i.e., <7.5%), thereby indicating that even under these stringent conditions, these scaffolds will be able to work properly. The scaffolds impregnated with propolis showed a lower % of cell viability using hDP-MSCs on the 3rd day, but these values increased on the 7th day. These scaffolds exhibited antibacterial activity against the monospecies cultures of S. aureus and S. epidermidis and their cocultures. The samples without propolis loads did not show inhibition halos, whereas those loaded with EEP exhibited halos of 17.42 ± 0.2 mm against S. aureus and 12.9 ± 0.5 mm against S. epidermidis. These results made the scaffolds possible bone substitutes that exert control over species with a proliferative capacity for the biofilm-formation processes required for typical severe infectious processes.

Development of 3D-Printed Collagen Scaffolds with In-Situ Synthesis of Silver Nanoparticles

UV-irradiation method has grown as an alternative approach to in situ synthetize silver nanoparticles (AgNPs) for avoiding the use of toxic reducing agents. In this work, an antimicrobial material by in situ synthesizing AgNPs within 3D-printed collagen-based scaffolds (Col-Ag) was developed. By modifying the concentration of AgNO₃ (0.05 and 0.1 M) and UV irradiation time (2 h, 4 h, and 6 h), the morphology and size of the in situ prepared AgNPs could be controlled. As a result, star-like silver particles of around 23 ± 4 μm and spherical AgNPs of 220 ± 42 nm were obtained for Ag 0.05 M, while for Ag 0.1 M cubic particles from 0.3 to 1.0 μm and round silver precipitates of 3.0 ± 0.4 μm were formed in the surface of the scaffolds at different UV irradiation times. However, inside the material AgNPs of 10-28 nm were obtained. The DSC thermal analysis showed that a higher concentration of Ag stabilizes the 3D-printed collagen-based scaffolds, while a longer UV irradiation interval produces a decrease in the denaturation temperature of collagen. The enzymatic degradation assay also revealed that the in situ formed AgNPs act as stabilizing and reinforcement agent which also improve the swelling capacity of collagen-based material. Finally, antimicrobial activity of Col-Ag was studied, showing high bactericidal efficiency against Gram-negative (Escherichia coli) and Gram-positive (Staphylococcus aureus) bacteria. These results showed that the UV irradiation method was really attractive to modulate the size and shape of in situ synthesized AgNPs to develop antimicrobial 3D-printed collagen scaffolds with different thermal, swelling and degradation properties.

Liposomes encapsulating novel antimicrobial peptide Omiganan: Characterization and its pharmacodynamic evaluation in atopic dermatitis and psoriasis mice model

Omiganan is a novel 12 amino acid synthetic cationic peptide from the cathelicidin family. Omiganan possesses antimicrobial action against a wide range of microbes, including gram-positive and gram-negative bacteria and fungi. Omiganan mainly acts by depolarizing the cytoplasmic membrane, resulting in cellular disruption and death. Apart from its antimicrobial effect, Omiganan also has anti-inflammatory activity. The present investigation aimed to evaluate and compare the efficacy of Omiganan liposomal gel with conventional formulations (Omiganan gel and lotion) in atopic dermatitis (AD) and psoriasis mice animal models. Liposomes encapsulating Omiganan were prepared using the reverse-phase evaporation technique and incorporated into Carbopol 934P gel. The optimized Omiganan liposomes were then characterized for various physicochemical parameters such as vesicle size, shape and surface morphology, zeta-potential, rheological parameters, in-vitro drug release, ex-vivo skin permeation/deposition, in-vitro antimicrobial activity, proteolytic stability, and cellular toxicity and uptake studies. Liposomes exhibited 72 % encapsulation with 7.8 % loading efficacy, a vesicle size, and zeta potential of 120 nm and - 17.2 mv, respectively. Moreover, Omiganan liposomal gel demonstrated controlled release and a better permeation profile than conventional formulations. A substantial reduction in levels of pro-inflammatory cytokines and improvement in AD and psoriatic lesions were achieved by Omiganan liposomal gel compared to Omiganan gel and lotion-based formulations. The present study confirms that Omiganan liposomal formulation can be an effective, safe, and novel alternative treatment approach in atopic dermatitis and psoriasis.

From propolis to nanopropolis: An exemplary journey and a paradigm shift of a resinous substance produced by bees

Propolis, a natural resinous mixture produced by honey bees is poised with diverse biological activities. Owing to the presence of flavonoids, phenolic acids, terpenes, and sesquiterpenes, propolis has garnered versatile applications in pharmaceutical industry. The biopharmaceutical issues associated with propolis often beset its use as being too hydrophobic in nature; it is not absorbed in the body well. To combat the problem, various nanotechnological approaches for the development of novel drug delivery systems are generally applied to improve its bioavailability. This paradigm shift and transition of conventional propolis to nanopropolis are evident from the literature wherein a multitude of studies are available on nanopropolis with improved bioavailability profile. These approaches include preparation of gold nanoparticles, silver nanoparticles, magnetic nanoparticles, liposomes, liquid crystalline formulations, solid lipid nanoparticles, mesoporous silica nanoparticles, etc. Nanopropolis has further been explored to assess the potential benefits of propolis for the development of futuristic useful products such as sunscreens, creams, mouthwashes, toothpastes, and nutritional supplements with improved solubility, bioavailability, and penetration profiles. However, more high-quality clinical studies assessing the effects of propolis either alone or in combination with synthetic drugs as well as natural products are warranted and its safety needs to be firmly established.

Effect of Propolis Paste and Mouthwash Formulation on Healing after Teeth Extraction in Periodontal Disease

This study investigated the antimicrobial effects of a mouthwash containing propolis and the effect of a propolis paste formulation on dental healing after teeth extraction in patients with periodontal disease. In the mouthwash experience, the population comprised 40 patients, which were divided as follows: the control mouthwash, 0.2% chlorhexidine (v/v) mouthwash, 2% (w/v) propolis mouthwash, and propolis + chlorhexidine mouthwash. The study of the propolis paste comprised a population of 60 patients with periodontal disease, and a total of 120 symmetric tooth extractions were performed. Propolis showed antimicrobial activity by itself, and especially with the chlorhexidine association. Three days after surgery in the teeth treated with control paste, only 13.4% had completely healed; however, with propolis paste, in 90% of the periodontal sockets, healing was complete. In addition, a reduction in Streptococci mutans and Lactobacilli cfu was observed with propolis, and especially with the association of chlorhexidine + propolis. Propolis mouthwash reduced bacterial proliferation, especially in association with chlorhexidine. Propolis paste is a viable alternative for socket healing after dental extraction. The knowledge gained from these findings will provide a foundation for similar propolis therapies in order to improve the healing process after dental surgery.

Exploration of Bioengineered Scaffolds Composed of Thermo-Responsive Polymers for Drug Delivery in Wound Healing

Innate and adaptive immune responses lead to wound healing by regulating a complex series of events promoting cellular cross-talk. An inflammatory response is presented with its characteristic clinical symptoms: heat, pain, redness, and swelling. Some smart thermo-responsive polymers like chitosan, polyvinylpyrrolidone, alginate, and poly(ε-caprolactone) can be used to create biocompatible and biodegradable scaffolds. These processed thermo-responsive biomaterials possess 3D architectures similar to human structures, providing physical support for cell growth and tissue regeneration. Furthermore, these structures are used as novel drug delivery systems. Locally heated tumors above the polymer lower the critical solution temperature and can induce its conversion into a hydrophobic form by an entropy-driven process, enhancing drug release. When the thermal stimulus is gone, drug release is reduced due to the swelling of the material. As a result, these systems can contribute to the wound healing process in accelerating tissue healing, avoiding large scar tissue, regulating the inflammatory response, and protecting from bacterial infections. This paper integrates the relevant reported contributions of bioengineered scaffolds composed of smart thermo-responsive polymers for drug delivery applications in wound healing. Therefore, we present a comprehensive review that aims to demonstrate these systems' capacity to provide spatially and temporally controlled release strategies for one or more drugs used in wound healing. In this sense, the novel manufacturing techniques of 3D printing and electrospinning are explored for the tuning of their physicochemical properties to adjust therapies according to patient convenience and reduce drug toxicity and side effects.

The Potential of Honeybee Products for Biomaterial Applications

The development of biomaterials required continuous improvements in their properties for new tissue engineering applications. Implants based on biocompatible materials and biomaterial-based dressings are susceptible to infection threat; moreover, target tissues can suffer injuring inflammation. The inclusion of nature-derived bioactive compounds usually offers a suitable strategy to expand or increase the functional properties of biomaterial scaffolds and can even promote tissue healing. Honey is traditionally known for its healing property and is a mixture of phytochemicals that have a proven reputation as antimicrobial, anti-inflammatory, and antioxidant agents. This review discusses on the potential of honey and other honeybee products for biomaterial improvements. Our study illustrates the available and most recent literature reporting the use of these natural products combined with different polymeric scaffolds, to provide original insights in wound healing and other tissue regenerative approaches.