Skin Wound Healing Process and New Emerging Technologies for Skin Wound Care and Regeneration

Phytochemical Characterization and Assessment of the Wound Healing Properties of Three Eurasian Propolis

OBJECTIVES

The objective of this study is to evaluate the wound healing potential of Eurasian propolis by analyzing the phytochemical profile and the biological effects of three representative propolis samples.

METHODS

Specific colorimetric assays were used to estimate the total phenolic and flavonoid contents and the triterpenoids content. Some of the main components of Eurasian propolis (pinocembrin, pinobanksin, CAPE, chrysin and galangin) were analyzed using HPLC-DAD. Scavenging activity and total antioxidant capacity were assessed through DPPH and ORAC assays, respectively. Human keratinocyte, fibroblast, and monocytic cell lines were used for the biological in vitro analyses. The direct wound healing properties were tested through scratching assays and ELISA kits for the assessment of the production of growth factors (FGF-7, Latency Associated Peptide-LAP), while the indirect effects were evaluated through the estimation of the levels of MMP9, IL-1β, IL-8, and TNF-α using ELISA kits together with a cell-free test on the inhibition capacity on collagenases. Network Pharmacology analysis was employed to further explore possible mechanisms of the action of propolis on the healing process.

RESULTS

The analyses confirmed the high phenolic content of Eurasian propolis (142.50-211.30 mg GAE/g), dominated by flavonoids (95.50-196.80 mg Galangin Equivalents/g), and terpenes (431.50-650.00 mg β-sitosterol Equivalents/g), while also verifying the significant antioxidant (4.9-8.9 mM/g Trolox Equivalents) and antiradical (DPPH IC50 26.1-54.4 μg/mL) activities. The samples showed indirect wound healing properties by mitigating inflammation and remodeling (reduced IL-1β and MMP9) and potentially modulating the immune response (upregulated IL-8). In vitro studies confirmed these effects, demonstrating decreased MMP9 production and collagenase inhibition when cells were co-treated with propolis and a stressor. Propolis also suppressed IL-1β release in fibroblasts, although its impact on TNF-α was inconclusive. Notably, co-treatment upregulated IL-8 in monocytes, suggesting a potential immunomodulatory role.

CONCLUSIONS

Eurasian propolis may not directly stimulate cell proliferation during wound healing. Its anti-inflammatory and immunomodulatory properties could indicate an indirect contribution in helping the process.

3D Bilayered Hydrogel and Nanofiber Multifunctional Sponge Dressing: An Efficacious Healing Agent for Chronic Wound Healing

Chronic wound management using biomaterial-based dressings has significantly impacted the standard and efficiency of wound healing. However, various available wound healing aids are ineffective in treating deep open injuries and chronic wounds such as diabetic wounds. Herein, we developed a 3D bilayered multifunctional sponge, which addresses the structural and functional issues faced by biomaterial dressings in treating deep and chronic wounds. The 3D bilayered sponge consists of a hydrogel base functionalized with wound healing peptide (Tylotoin)-carrying nanoparticles and topped with a nanofiber layer functionalized with an antimicrobial peptide (LLKKK18). The 3D bilayered sponge, with its highly porous, elastic, and enhanced fluid absorption ability, makes it a suitable wound treatment aid. The developed multifunctional 3D sponge shows antibacterial action and promotes a microenvironment similar to the extracellular matrix (ECM) in regulating dermal cell survival and migration. Study in a full-thickness skin defect diabetic mouse model has shown that the developed 3D bilayered sponge accelerated wound closure and promoted functional skin regeneration through reduced inflammation, faster granulation tissue formation, re-epithelialization, neovascularization, and skin appendage restoration, which make the developed 3D bilayered multifunctional sponge an efficient and advanced chronic wound management aid with potential for future clinical application.

Current advances in the development of microRNA-integrated tissue engineering strategies: a cornerstone of regenerative medicine

Regenerative medicine is an innovative scientific field focused on repairing, replacing, or regenerating damaged tissues and organs to restore their normal functions. A central aspect of this research arena relies on the use of tissue-engineered scaffolds, which serve as structural supports that mimic the extracellular matrix, providing an environment that orchestrates cell growth and tissue formation. Remarkably, the therapeutic efficacy of these scaffolds can be improved by harnessing the properties of other molecules or compounds that have crucial roles in healing and regeneration pathways, such as phytochemicals, enzymes, transcription factors, and non-coding RNAs (ncRNAs). In particular, microRNAs (miRNAs) are a class of tiny (20-24 nt), highly conserved ncRNAs that play a critical role in the regulation of gene expression at the post-transcriptional level. Accordingly, miRNAs are involved in a myriad of biological processes, including cell differentiation, proliferation, and apoptosis, as well as tissue regeneration, angiogenesis, and osteogenesis. On this basis, over the past years, a number of research studies have demonstrated that miRNAs can be integrated into tissue-engineered scaffolds to create advanced therapeutic platforms that precisely modulate cellular behavior and offer a controlled and targeted release of miRNAs to optimize tissue repair and regeneration. Therefore, in this current review, we discuss the most recent advances in the development of miRNA-loaded tissue-engineered scaffolds and provide an overview of the future outlooks that should be aborded in this area of study in order to lay the groundwork for the clinical translation of these tissue engineering approaches.

Epidermal Growth Factor Intralesional Delivery in Chronic Wounds: The Pioneer and Standalone Technique for Reversing Wound Chronicity and Promoting Sustainable Healing

The early expectations about growth factors' (GFs') discovery as an undisputed therapeutic solution for chronic wounds progressively eclipsed when they failed to accelerate acute wound closure and restore the healing trajectory of stagnant ulcers. Critical knowledge about chronic wound biology and GF pharmacology was a conundrum at that time. Diabetes undermines keratinocytes' and fibroblasts' physiology, impairing skin healing abilities. Diabetic ulcers, as other chronic wounds, are characterized by hyperinflammation, unbalanced proteolytic activity, catabolism, and free radical cytotoxicity. This hostile scenario for the chemical stability, integrity, and functionality of GFs led to the conclusion that topical administration may jeopardize GFs' clinical effectiveness. Epidermal growth factor (EGF) has a proximal position in tissues homeostasis by activating survival and mitogenic pathways from embryonic life to adulthood. Seminal experiments disclosed unprecedented pharmacological bounties of parenterally administered EGF. Accordingly, the experience accumulated for more than 20 years of EGF intralesional infiltration of diabetic wound bottoms and edges has translated into sustained healing responses, such as low recurrences and amputation rates. This delivery route, in addition to being safe and tolerated, has shown to restore a variety of circulating biochemical markers ordinarily disturbed in diabetic conditions. EGF infiltration triggers a cascade of local fibroblast reactions, supporting its molecular integrity, prolonged mean residence time, and ultimately eliciting its receptor trafficking and nuclear translocation. The intralesional delivery route seems to warrant that EGF reaches wound fibroblasts' epigenetic core, mitigating the consequences of metabolic memory imprinting.

Electrical stimulation: a novel therapeutic strategy to heal biological wounds

Electrical stimulation (ES) has emerged as a powerful therapeutic modality for enhancing biological wound healing. This non-invasive technique utilizes low-level electrical currents to promote tissue regeneration and expedite the wound healing process. ES has been shown to accelerate wound closure, reduce inflammation, enhance angiogenesis, and modulate cell migration and proliferation through various mechanisms. The principle goal of wound management is the rapid recovery of the anatomical continuity of the skin, to prevent infections from the external environment and maintain homeostasis conditions inside. ES at the wound site is a compelling strategy for skin wound repair. Several ES applications are described in medical literature like AC, DC, and PC to improve cutaneous perfusion and accelerate wound healing. This review aimed to evaluate the primary factors and provides an overview of the potential benefits and mechanisms of ES in wound healing, and its ability to stimulate cellular responses, promote tissue regeneration, and improve overall healing outcomes. We also shed light on the application of ES which holds excellent promise as an adjunct therapy for various types of wounds, including chronic wounds, diabetic ulcers, and surgical incisions.

Development and Biocompatibility Assessment of Decellularized Porcine Uterine Extracellular Matrix-Derived Grafts

Biomaterials derived from biological matrices have been widely investigated due to their great therapeutic potential in regenerative medicine, since they are able to induce cell proliferation, tissue remodeling, and angiogenesis in situ. In this context, highly vascularized and proliferative tissues, such as the uterine wall, present an interesting source to produce acellular matrices that can be used as bioactive materials to induce tissue regeneration. Therefore, this study aimed to establish an optimized protocol to generate decellularized uterine scaffolds (dUT), characterizing their structural, compositional, and biomechanical properties. In addition, in vitro performance and in vivo biocompatibility were also evaluated to verify their potential applications for tissue repair. Results showed that the protocol was efficient to promote cell removal, and dUT general structure and extracellular matrix composition remained preserved compared with native tissue. In addition, the scaffolds were cytocompatible, allowing cell growth and survival. In terms of biocompatibility, the matrices did not induce any signs of immune rejection in vivo in a model of subcutaneous implantation in immunocompetent rats, demonstrating an indication of tissue integration after 30 days of implantation. In summary, these findings suggest that dUT scaffolds could be explored as a biomaterial for regenerative purposes, which is beyond the studies in the reproductive field.

The Angiogenic Repertoire of Stem Cell Extracellular Vesicles: Demystifying the Molecular Underpinnings for Wound Healing Applications

Stem cells-derived extracellular vesicles (SC-EVs) have emerged as promising therapeutic agents for wound repair, recapitulating the biological effects of parent cells while mitigating immunogenic and tumorigenic risks. These EVs orchestrate wound healing processes, notably through modulating angiogenesis-a critical event in tissue revascularization and regeneration. This study provides a comprehensive overview of the multifaceted mechanisms underpinning the pro-angiogenic capacity of EVs from various stem cell sources within the wound microenvironment. By elucidating the molecular intricacies governing their angiogenic prowess, we aim to unravel the mechanistic repertoire underlying their remarkable potential to accelerate wound healing. Additionally, methods to enhance the angiogenic effects of SC-EVs, current limitations, and future perspectives are highlighted, emphasizing the significant potential of this rapidly advancing field in revolutionizing wound healing strategies.

Revealing the molecular mechanisms in wound healing and the effects of different physiological factors including diabetes, age, and stress

Wounds are the common fates in various microbial infections and physical damages including accidents, surgery, and burns. In response, a healthy body with a potent immune system heals that particular site within optimal time by following the coagulation, inflammation, proliferation, and remodeling phenomenon. However, certain malfunctions in the body due to various diseases particularly diabetes and other physiological factors like age, stress, etc., prolong the process of wound healing through various mechanisms including the Akt, Polyol, and Hexosamine pathways. The current review thoroughly explains the wound types, normal wound healing mechanisms, and the immune system's role. Moreover, the mechanistic role of diabetes is also elaborated comprehensively.

Accelerated, injectable, self-healing, scarless wound dressings using rGO reinforced dextran/chitosan hydrogels incorporated with PDA-loaded asiaticoside

The process of wound healing is intricate and complex, necessitating the intricate coordination of various cell types and bioactive molecules. Despite significant advances, challenges persist in achieving accelerated healing and minimizing scar formation. Herein, a multifunctional hydrogel engineered via dynamic Schiff base crosslinking between oxidized dextran and quaternized chitosan, reinforced with reduced graphene oxide (rGO) is reported. The resulting OQG hydrogels demonstrated injectability to aid in conforming to irregular wound geometries, rapid self-healing to maintain structural integrity and adhesion for intimate integration with wound beds. Moreover, the developed hydrogels possessed antioxidant and antibacterial activities, mitigating inflammation and preventing infection. The incorporation of conductive rGO further facilitated the transmission of endogenous electrical signals, stimulating cell migration and tissue regeneration. In addition, the polydopamine-encapsulated asiaticoside (AC@PDA) nanoparticles were encapsulated in OQG hydrogels to reduce scar formation during in vivo evaluations. In vitro results confirmed the histocompatibility of the hydrogels to promote cell migration. The recovery of the full-thickness rat wounds revealed that these designed OQG hydrogels with the incorporation of AC@PDA nanoparticles could accelerate wound healing, reduce inflammation, facilitate angiogenesis, and minimize scarring when implemented. This multifunctional hydrogel system offers a promising strategy for enhanced wound management and scarless tissue regeneration, addressing the multifaceted challenges in wound care.

Production and Characterization of Electrospun Chitosan, Nanochitosan and Hyaluronic Acid Membranes for Skin Wound Healing

The development of new wound dressings made from biomaterials, which offer a better cost-benefit ratio and accelerate the healing process, is increasing nowadays. Various biopolymers can be electrospun to form functional membranes for wound healing. Therefore, in this study, chitosan and nanochitosan membranes with or without hyaluronic acid were prepared using the electrospinning technique, characterized and evaluated in the healing of skin wounds in rats. Chitosan and nanochitosan solutions, with or without hyaluronic acid, were prepared at concentrations of 1%-4% using PEO (polyethylene oxide) and subjected to the electrospinning process to obtain membranes characterized by scanning electron microscopy (SEM), mechanical tests, and antimicrobial activity. The healing effect of the membranes was evaluated by monitoring the area of the lesions, contraction of the wounds, histologic analysis, and induction of pro-inflammatory cytokine (IL-1 α and TNF-α) production in rats. The nanochitosan and nanochitosan membranes with hyaluronic acid achieved greater fiber diameter and uniformity, resistance, elasticity, and thermal stability, in addition to good adhesion to the wound bed and permeation capacity. Despite not presenting antimicrobial activity in vitro, they contributed to the production of pro-inflammatory interleukins in the animals tested, provided physical protection, reduced the wound area more markedly until the seventh day of the evaluation, with an acceleration of the healing process and especially when functionalized with hyaluronic acid. These results indicate that the membranes may be promising for accelerating the healing process of chronic wounds in humans.

Hydrogels with Antioxidant Microparticles Systems Based on Hyaluronic Acid for Regenerative Wound Healing

This research focuses on the synthesis of hydrogels exhibiting enhanced antioxidant properties derived from hyaluronic acid (HA) and poly(ethylene brassylate-co-squaric acid) (PEBSA), a copolymacrolactone that have the ability to be used in drug delivery applications. Quercetin (Q), a bioflavonoid with strong antioxidant properties, is employed as a bioactive compound. The biomolecule is encapsulated in the polymeric network using different entrapment techniques, including the initial formation of a complex between PEBSA and Q, which is demonstrated through the dynamic light scattering technique. Fourier transform infrared spectroscopy (FT-IR) and rheological studies confirm the formation of the hydrogels, revealing the occurrence of physical interactions between the synthetic polymer and the polysaccharide. Moreover, the hydrogels demonstrate biocompatible properties after direct contact with the HDFa cell line and antioxidant properties, as revealed by DPPH tests.

Concentration-Dependent Effects of MXene Nanocomposite-Loaded Carboxymethyl Cellulose on Wound Healing

Nanoparticles (NPs) have emerged as a promising solution for many biomedical applications. Although not all particles have antimicrobial or regenerative properties, certain NPs show promise in enhancing wound healing by promoting tissue regeneration, reducing inflammation, and preventing infection. Integrating various NPs can further enhance these effects. Herein, the zinc oxide (ZnO)-MXene-Ag nanocomposite was prepared, and the conjugation of its three components was confirmed through scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) mapping analysis. In vitro analysis using the agar well diffusion technique demonstrated that ZnO-MXene-Ag nanocomposite exhibited high antimicrobial efficacy, significantly inhibiting Escherichia coli, Salmonella, and Candida albicans, and showing enhanced potency when combined with tetracycline, resulting in a 2.6-fold increase against Staphylococcus and a 2.4-fold increase against Pseudomonas. The efficacy of nanocomposite-loaded carboxymethyl cellulose (CMC) gel on wound healing was investigated using varying concentrations (0, 1, 5, and 10 mg/mL). Wound healing was monitored over 21 days, with results indicating that wounds treated with 1 mg/mL ZnO-MXene-Ag gel exhibited superior healing compared to the control group (0 mg/mL), with significant improvements noted from Day 3 onward. Conversely, higher concentrations (10 mg/mL) resulted in reduced healing efficiency, particularly notable on Day 15. In conclusion, the ZnO-MXene-Ag nanocomposite-loaded CMC gel is a promising agent for enhanced wound healing and antimicrobial applications. These findings highlight the importance of optimizing NP concentration to maximize therapeutic benefits while minimizing potential cytotoxicity.

Enhancing cellular affinity for skin disorders: Electrospun polyurethane/collagen nanofiber mats coated with phytoceramides

Although the use of thermoplastic polyurethane (Tpu) nanofiber mats as wound dressings is of great interest due to their mechanical properties, they are hindered by their poor wettability and bioavailability. In this study, we aimed to improve the cellular affinity of Tpu nanofiber mats for skin disorders by incorporating extracted collagen (Col) from tendons and physically mixed with a layer of phytoceramides (Phyto) to produce TpuCol@X-Phyto mats in which the weight % of Phyto relatively to the weight of the solution was X = 0.5, 1.0, or 1.5 wt% via facile electrospinning approach. The collective observations strongly indicate the successful incorporation and retention of Phyto within the TpuCol architecture. An increase in the Phyto concentration decreased the water contact angle from 69.4° ± 3.47° to 57.9° ± 2.89°, demonstrating improvement in the hydrophilicity of Tpu and binary blend TpuCol nanofiber mats. The mechanical property of 1.0 wt% Phyto aligns with practical requirements owing to the presence of two hydroxyl groups and the amide linkage likely contributing to various hydrogen bonds, providing mechanical strength to the channel structure and a degree of rigidity essential for transmitting mechanical stress. The proliferation of human skin fibroblast (HSF) peaked significantly 100 % with TpuCol@X-Phyto mats coated for X =1.0 and 1.5 wt% of Phyto. Electrospun scaffolds with the highest Phyto content have shown the lowest degree of hemolysis, demonstrating the high level of compatibility between them and blood. The TpuCol@1.5Phyto mat also demonstrated higher efficacy in antibacterial and antioxidant activities, achieving a rate of DPPH radical scavenging of 83.3 % for this latter property. The most notable wound closure among all tested formulations was attributed to higher Phyto. Thus, the developed TpuCol@1.5Phyto nanofiber formula exhibited enhanced healing in an in vitro epidermal model.

The role of adipose tissue-derived stromal cells, macrophages and bioscaffolds in cutaneous wound repair

Skin healing is a complex and dynamic physiological process that follows mechanical alteration of the skin barrier. Under normal conditions, this complex process can be divided into at least three continuous and overlapping phases: an inflammatory reaction, a proliferative phase that leads to tissue reconstruction and a phase of tissue remodeling. Macrophages critically contribute to the physiological cascade for tissue repair. In fact, as the inflammatory phase progresses, macrophage gene expression gradually shifts from pro-inflammatory M1-like to pro-resolutive M2-like characteristics, which is critical for entry into the repair phase. A dysregulation in this macrophage' shift phenotype leads to the persistence of the inflammatory phase. Mesenchymal stromal cells and specifically the MSC-derived from adipose tissue (ADSCs) are more and more use to treat inflammatory diseases and several studies have demonstrated that ADSCs promote the wound healing thanks to their neoangiogenic, immunomodulant and regenerative properties. In several studies, ADSCs and macrophages have been injected directly into the wound bed, but the delivery of exogenous cells directly to the wound raise the problem of cell engraftment and preservation of pro-resolutive phenotype and viability of the cells. Complementary approaches have therefore been explored, such as the use of biomaterials enriched with therapeutic cell to improve cell survival and function. This review will present a background of the current scaffold models, using adipose derived stromal-cells and macrophage as therapeutic cells for wound healing, through a discussion on the potential impact for future applications in skin regeneration. According to the PRISMA statement, we resumed data from investigations reporting the use ADSCs and bioscaffolds and data from macrophages behavior with functional biomaterials in wound healing models. In the era of tissue engineering, functional biomaterials, that can maintain cell delivery and cellular viability, have had a profound impact on the development of dressings for the treatment of chronic wounds. Promising results have been showed in pre-clinical reports using ADSCs- and macrophages-based scaffolds to accelerate and to improve the quality of the cutaneous healing.

Quercus glauca Acorn Seed Coat Extract Promotes Wound Re-Epithelialization by Facilitating Fibroblast Migration and Inhibiting Dermal Inflammation

The skin, recognized as the largest organ in the human body, serves a vital function in safeguarding against external threats. Severe damage to the skin can pose significant risks to human health. There is an urgent requirement for safe and effective therapies for wound healing. While phytotherapy has been widely utilized for various health conditions, the potential of Quercus glauca in promoting wound healing has not been thoroughly explored. Q. glauca is a cultivated crop known for its abundance of bioactive compounds. This study examined the wound-healing properties of Quercus glauca acorn seed coat water extract (QGASE). The findings from the study suggest that QGASE promotes wound closure in HF cells by upregulating essential markers related to the wound-healing process. Additionally, QGASE demonstrates antioxidant effects, mitigating oxidative stress and aiding in recovery from injuries induced by H2O2. In vivo experiments provide additional substantiation supporting the efficacy of QGASE in enhancing wound healing. The collective results indicate that QGASE may be a promising candidate for the development of innovative therapeutic strategies aimed at enhancing skin wound repair.

Copper Nanoparticle Loaded Electrospun Patches for Infected Wound Treatment: From Development to In-Vivo Application

This study investigates the development and application of electrospun wound dressings based on polylactic acid (PLA) nanofibers, chitosan, and copper nanoparticles (CuNPs) for the treatment of purulent skin wounds. The materials were evaluated for their structural, antibacterial, and wound healing properties using an animal model. PLA/Ch-CuNPs demonstrated the most significant antibacterial activity against Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa, surpassing the other tested materials. The integration of CuNPs into the nanofiber matrices not only enhanced the antimicrobial efficacy but also maintained the structural integrity and biocompatibility of the dressings. In vivo experiments using a rat model showed that PLA/Ch-CuNPs facilitated faster wound healing with reduced exudative and inflammatory responses compared to PLA alone or PLA-CuNPs. Histological and immunohistochemical assessments revealed that the combination of PLA, chitosan, and CuNPs mitigated the inflammatory processes and promoted tissue regeneration more effectively. However, this study identified potential toxicity related to copper ions, emphasizing the need for careful optimization of CuNP concentrations. These findings suggest that PLA/Ch-CuNPs could serve as a potent, cost-effective wound dressing with broad-spectrum antibacterial properties, addressing the challenge of antibiotic-resistant infections and enhancing wound healing outcomes.

A review of biopolymer-based hydrogels and IoT integration for enhanced diabetes diagnosis, management, and treatment

The prevalence of diabetes has been increasing globally, necessitating innovative approaches beyond conventional blood sugar monitoring and insulin control. Diabetes is associated with complex health complications, including cardiovascular diseases. Continuous Glucose Monitoring (CGM) devices, though automated, have limitations such as irreversibility and interference with bodily fluids. Hydrogel technologies provide non-invasive alternatives to traditional methods, addressing the limitations of current approaches. This review explores hydrogels as macromolecular biopolymeric materials capable of absorbing and retaining a substantial amount of water within their structure. Due to their high-water absorption properties, these macromolecules are utilized as coating materials for wound care and diabetes management. The study emphasizes the need for early diagnosis and monitoring, especially during the COVID-19 pandemic, where heightened attention to diabetic patients is crucial. Additionally, the article examines the role of the Internet of Things (IoT) and machine learning-based systems in enhancing diabetes management effectiveness. By leveraging these technologies, there is potential to revolutionize diabetes care, providing more personalized and proactive solutions. This review explores cutting-edge hydrogel-based systems as a promising avenue for diabetes diagnosis, management, and treatment, highlighting key biopolymers and technological integrations.

A review of polysaccharide hydrogels as materials for skin repair and wound dressing: Construction, functionalization and challenges

Hydrogels can imitate the extracellular matrix, therefore facilitating the creation of an ideal healing environment for wounds. Consequently, they are popular as a material choice for wound dressings. Polysaccharides have been widely used in wound dressings due to their good biocompatibility and degradability. In this study, we first discuss skin and wound physiology before summarizing the methods for producing hydrogels from polysaccharides and their derivatized. These include not just normal polysaccharides like chitosan, cellulose, and alginate, but also Chinese medicinal polysaccharides with therapeutic properties. Then, strategies for causing hydrogel production from polysaccharides or their derivatives are briefly explained. Finally, the functions of hydrogel dressings are reviewed, including antibacterial, antioxidant, and adhesive properties, as well as the methods for achieving these properties. Furthermore, current issues and concerns are discussed, with the goal of providing fresh paths for the development of future wound dressings.

Wound Healing and Acute Dermal Toxicity Studies of Ludwigia octovalvis (Jacq.) P. H. Raven (Onagraceae) in Sprague-Dawley Rats

Introduction

The aerial part of Ludwigia octovalvis has been used traditionally in some parts of Asia for the management of wounds owing to the presence of phytochemicals such as tannins, flavonoids, and triterpenoids among others. The incidence of wounds, their associated complications, and the cost of wound care are on the increase globally, therefore, the need to develop alternative wound care agents. The aim of this study was to scientifically investigate the wound healing potential of the ethanolic extract of L. octovalvis using the excision wound healing model in rats and also carry out an acute dermal toxicity investigation of the plant extract.

Method

A 70% ethanol extract of L. octovalvis was prepared for the wound healing activity using the excision wound healing model in Sprague-Dawley rats. Aqueous creams (1, 3, and 10%) were prepared and topically applied to the wounds once daily according to the groups of animals. The wounds were assessed for rates of wound closure on days 3, 5, 7, 9, and 11. Re-epithelialization periods were also determined. Sections of wound tissues obtained on day 13 were subjected to histological investigations. An acute dermal toxicity of the plant extract was investigated.

Results

L. octovalvis treatment (1, 3, and 10%) exhibited a mean percentage wound contraction range of 85.36 ± 7.22-94.14 ± 2.23 on day 11. The extract exhibited re-epithelialization periods of 17.3 ± 1.2, 19.8 ± 2.6, and 16.0 ± 1.7 days for the 1, 3, and 10% extract creams, respectively, whereas the cream-only and 1% silver sulfadiazine treatments resulted in a re-epithelialization period of greater than 28 days. Histopathological investigation revealed enhanced fibroblast infiltration and collagen deposition in the treatment groups. No adverse reaction was observed in the acute dermal toxicity study.

Conclusions

Extract of L. octovalvis exhibited wound healing by enhancing wound contraction, re-epithelialization, fibroblast infiltration, and collagen deposition at the wound site. The extract did not exhibit any toxic reaction in the acute dermal toxicity study.

Fabrication of fiber-particle structures by electrospinning/electrospray combination as an intrinsic antioxidant and oxygen-releasing wound dressing

In this study, we employed a combination of electrospinning and electrospray techniques to fabricate wound dressings with a particle-fiber structure, providing dual characteristics of oxygen-releasing and intrinsic antioxidant properties, simultaneously. The electrospun part of the dressing was prepared from a blend of polycaprolactone/gallic acid-grafted-gelatin (GA-g-GE), enabling intrinsic ROS scavenging. To the best of our knowledge, this is the first time that PCL/GA-g-GE was fabricated by electrospinning. Furthermore, polyvinyl pyrrolidone (PVP) microparticles, containing calcium peroxide nanoparticles (CNPs), were considered as the oxygen production agent through the electrospray part. The CNP content was 1% and 3% w/w of PVP while biopolymer:PCL was 10% w/w. The fabricated structures were characterized in terms of fiber/particle morphology, elemental analysis, oxygen release behavior, ROS inhibition capacity, and water contact angle assessments. The covalent bonding of gallic acid to gelatin was confirmed by 1H-NMR, UV spectroscopy, and FTIR. According to the SEM results, the morphology of the prepared PCL/biopolymer fibers was bead-free and with a uniform average diameter. The analysis of released oxygen showed that by increasing the weight percentage of CNPs from 1 to 3 wt%, the amount of released oxygen increased from 120 mmHg to 195 mmHg in 24 h, which remained almost constant until 72 h. The obtained DPPH assay results revealed that the introduction of GA-g-GE into the fibrous structure could significantly improve the antioxidant properties of wound dressing compared to the control group without CNPs and modified gelatine. In vitro, the fabricated wound dressings were evaluated in terms of biocompatibility and the potential of the dressing to protect human dermal fibroblasts under oxidative stress and hypoxia conditions by an MTT assay. The presence of GA-g-GE led to remarkable protection of the cells against oxidative stress and hypoxia conditions. In vivo studies revealed that the incorporation of intrinsic ROS inhibition and oxygen-releasing properties could significantly accelerate the wound closure rate during the experimental period (7, 14, and 21 days). Additionally, histopathological investigations in terms of H&E and Masson's trichrome staining showed that the incorporation of the two mentioned capabilities remarkably facilitated the wound-healing process.

Photo-Crosslinked Pro-Angiogenic Hydrogel Dressing for Wound Healing

Severe burns are one of the most devastating injuries, in which sustained inflammation and ischemia often delay the healing process. Pro-angiogenic growth factors such as vascular endothelial growth factor (VEGF) have been widely studied for promoting wound healing. However, the short half-life and instability of VEGF limit its clinical applications. In this study, we develop a photo-crosslinked hydrogel wound dressing from methacrylate hyaluronic acid (MeHA) bonded with a pro-angiogenic prominin-1-binding peptide (PR1P). The materials were extruded in wound bed and in situ formed a wound dressing via exposure to short-time ultraviolet radiation. The study shows that the PR1P-bonded hydrogel significantly improves VEGF recruitment, tubular formation, and cell migration in vitro. Swelling, Scanning Electron Microscope, and mechanical tests indicate the peptide does not affect the overall mechanical and physical properties of the hydrogels. For in vivo studies, the PR1P-bonded hydrogel dressing enhances neovascularization and accelerates wound closure in both deep second-degree burn and full-thickness excisional wound models. The Western blot assay shows such benefits can be related to the activation of the VEGF-Akt signaling pathway. These results suggest this photo-crosslinked hydrogel dressing efficiently promotes VEGF recruitment and angiogenesis in skin regeneration, indicating its potential for clinical applications in wound healing.

Evaluation of Biotechnological Active Peptides Secreted by Saccharomyces cerevisiae with Potential Skin Benefits

Biotechnological active peptides are gaining interest in the cosmetics industry due to their antimicrobial, anti-inflammatory, antioxidant, and anti-collagenase (ACE) effects, as well as wound healing properties, making them suitable for cosmetic formulations. The antimicrobial activity of peptides (2-10 kDa) secreted by Saccharomyces cerevisiae Ethanol-Red was evaluated against dermal pathogens using broth microdilution and challenge tests. ACE was assessed using a collagenase activity colorimetric assay, antioxidant activity via spectrophotometric monitoring of nitrotetrazolium blue chloride (NBT) reduction, and anti-inflammatory effects by quantifying TNF-α mRNA in lipopolysaccharides (LPS)-exposed dermal fibroblasts. Wound healing assays involved human fibroblasts, endothelial cells, and dermal keratinocytes. The peptides (2-10 kDa) exhibited antimicrobial activity against 10 dermal pathogens, with the Minimum Inhibitory Concentrations (MICs) ranging from 125 µg/mL for Staphylococcus aureus to 1000 µg/mL for Candida albicans and Streptococcus pyogenes. In the challenge test, peptides at their MICs reduced microbial counts significantly, fulfilling ISO 11930:2019 standards, except against Aspergillus brasiliensis. The peptides combined with MicrocareⓇ SB showed synergy, particularly against C. albicans and A. brasilensis. In vitro, the peptides inhibited collagenase activity by 41.8% and 94.5% at 250 and 1000 µg/mL, respectively, and demonstrated antioxidant capacity. Pre-incubation with peptides decreased TNF-α expression in fibroblasts, indicating anti-inflammatory effects. The peptides do not show to promote or inhibit the angiogenesis of endothelial cells, but are able to attenuate fibrosis, scar formation, and chronic inflammation during the final phases of the wound healing process. The peptides showed antimicrobial, antioxidant, ACE, and anti-inflammatory properties, highlighting their potential as multifunctional bioactive ingredients in skincare, warranting further optimization and exploration in cosmetic applications.

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.

Advancements in cell-based therapies for thermal burn wounds: a comprehensive systematic review of clinical trials outcomes

BACKGROUND

Burn trauma is one of the major causes of morbidity and mortality worldwide. The standard management of burn wounds consists of early debridement, dressing changes, surgical management, and split-thickness skin autografts (STSGs). However, there are limitations for the standard management that inclines us to find alternative treatment approaches, such as innovative cell-based therapies. We aimed to systematically review the different aspects of cell-based treatment approaches for burn wounds in clinical trials.

METHODS

A systematic search through PubMed, Medline, Embase, and Cochrane Library databases was carried out using a combination of keywords, including "Cell transplantation", "Fibroblast", "Keratinocyte", "Melanocyte", or "Stem Cell" with "Burn", "Burn wound", or "Burn injury". Firstly, titles and abstracts of the studies existing in these databases until "February 2024" were screened. Then, the selected studies were read thoroughly, and considering the inclusion and exclusion criteria, final articles were included in this systematic review. Moreover, a manual search was performed through the reference lists of the included studies to minimize the risk of missing reports.

RESULTS

Overall, 30 clinical trials with 970 patients were included in our study. Considering the type of cells, six studies used keratinocytes, nine used fibroblasts, eight used combined keratinocytes and fibroblasts, one study used combined keratinocytes and melanocytes, five used combined keratinocytes and fibroblasts and melanocytes, and one study used mesenchymal stem cells (MSCs). Evaluation of the preparation type in these studies showed that cultured method was used in 25 trials, and non-cultured method in 5 trials. Also, the graft type of 17 trials was allogeneic, and of 13 other trials was autologous.

CONCLUSIONS

Our study showed that employing cell-based therapies for the treatment of burn wounds have significant results in clinical studies and are promising approaches that can be considered as alternative treatments in many cases. However, choosing appropriate cell-based treatment for each burn wound is essential and depends on the situation of each patient.

Chitosan microflower-embedded gelatin sponges for advanced wound management and hemostatic applications

The study explored the antimicrobial, antibiofilm, and hemostatic properties of chitosan microflowers (CMF) in sponge form. The main objective was to enhance the preparation of CMF by employing varying quantities of calcium chloride (CaCl2) and tripolyphosphate (TPP). CMF was then combined with gelatin (GE) in different proportions to produce three sponge samples: CMF0@GE, CMF1@GE, and CMF2@GE. The CMF had a morphology like that of a flower and produced surfaces with a porous sponge-like structure. The antibacterial activity, as determined by the zone of inhibition (ZOI), increased with greater doses of CMF. Among the tested samples, CMF2@GE had the greatest activity against Pseudomonas aeruginosa, Klebsiella pneumoniae, Staphylococcus aureus, and Enterococcus faecium. CMF2@GE successfully suppressed biofilm formation, decreased clotting time to an average of 212.67 s, and exhibited excellent biocompatibility by preserving over 90 % viability of human skin fibroblast cells at dosages below 100 μg/mL. The results indicated that gelatin sponges filled with CMF have considerable promise as flexible medical instruments for wound healing and infection control.

Characterization of an Escherichia coli phage Tequatrovirus YZ2 and its application in bacterial wound infection

The increasing prevalence of drug-resistant Escherichia coli (E. coli) resulting from the excessive utilization of antibiotics necessitates the immediate exploration of alternative approaches to counteract pathogenic E. coli. Phages, with their unique antibacterial mechanisms, are considered promising candidates for treating bacterial infections. Herein, we isolated a lytic Escherichia phage Tequatrovirus YZ2 (phage YZ2), which belongs to the genus Tequatrovirus. The genome of phage YZ2 consists of 168,356 base pairs with a G + C content of 35.34% and 269 putative open reading frames (ORFs). Of these, 146 ORFs have been annotated as functional proteins associated with nucleotide metabolism, structure, transcription, DNA replication, translation, and lysis. In the mouse model of a skin wound infected by E. coli, phage YZ2 therapy significantly promoted the wound healing. Furthermore, histopathological analysis revealed reductions in IL-1β and TNF-α and increased VEGF levels, indicating the potential of phages as effective antimicrobial agents against E. coli infection.

Enhanced Mechanical Strength and Sustained Drug Release in Carrier-Free Silver-Coordinated Anthraquinone Natural Antibacterial Anti-Inflammatory Hydrogel for Infectious Wound Healing

The persistent challenge of healing infectious wounds and the rise of bacterial resistance represent significant hurdles in contemporary medicine. In this study, based on the natural small molecule drug Rhein self-assembly to form hydrogels and coordinate assembly with silver ions (Ag+), a sustained-release carrier-free hydrogel with compact structure is constructed to promote the repair of bacterial-infected wounds. As a broad-spectrum antimicrobial agent, Ag+ can avoid the problem of bacterial resistance caused by the abuse of traditional antibiotics. In addition, due to the slow-release properties of Rhein hydrogel, continuous effective concentration of Ag+ at the wound site can be ensured. The assembly of Ag+ and Rhein makes the hydrogel system with enhanced mechanical stability. More importantly, it is found that Rhein effectively promotes skin tissue regeneration and wound healing by reprogramming M1 macrophages into M2 macrophages. Further mechanism studies show that Rhein realizes its powerful anti-inflammatory activity through NRF2/HO-1 activation and NF-κB inhibition. Thus, the hydrogel system combines the excellent antibacterial properties of Ag+ with the excellent anti-inflammatory and tissue regeneration ability of Rhein, providing a new strategy for wound management with dual roles.

Exploring exudate viscosity: A rheological analysis of wound exudates

Exudate and its viscosity are critical in wound healing. Changes in viscosity can interfere with dressings properties as well as affect the diffusion of immune cells, nutrients, oxygen and bacteria. Current international standards for laboratory testing of wound dressings use a single low-viscosity solution, named as 'Test Solution A', which fails to simulate the diverse range of exudates encountered clinically. This study employs rheological analysis to characterise exudates viscosity, comparing cattle-derived samples to the test solution A. Results reveal non-Newtonian, shear-thinning behaviour in exudates, contrasting with the Newtonian behaviour of the test solution A. Although clinically classified as 'seropurulent', three exudate samples analysed at 37°C present with different viscosity at various shear rates, ranging from 30.8 (±14.7) to 6.5 (±1.9) mPas. Findings show that the current tests on dressings employing Test Solution A are missing the complexity of real exudates.

Sodium alginate-based multifunctional sandwich-like system for treating wound infections

Microbial colonization and development of infections in wounds is a sign of chronicity. The prevailing approach to manage and treat these wounds involves dressings. However, these often fail in effectively addressing infections, as they struggle to both absorb exudates and maintain optimal local moisture. The system here presented was conceptualized with a three-layer design: the outer layer made of a fibrous polycaprolactone (PCL) film, to act as a barrier for preventing microorganisms and impurities from reaching the wound; the intermediate layer formed of a sodium alginate (SA) hydrogel loaded with ampicillin (Amp) for fighting infections; and the inner layer comprised of a fibrous film of PCL and polyethylene glycol (PEG) for facilitating cell recognition and preventing wound adhesion. Thermal evaluations, degradation, wettability and release behavior testing confirmed the system resistance overtime. The sandwich demonstrated the capability for absorbing exudates (≈70 %) and exhibited a controlled release of Amp for up to 24 h. Antimicrobial testing was performed against Staphylococcus aureus and Escherichia coli, as representatives of Gram-positive and Gram-negative bacteria: >99 % elimination of bacteria. Cell cytotoxicity assessments showed high cytocompatibility levels, confirming the safety of the proposed sandwich system. Adhesion assays confirmed the system ease of detaching without mechanical effort (0.37 N). Data established the efficiency of the sandwich-like system, suggesting promising applications in infected wound care.

Advancements in employing two-dimensional nanomaterials for enhancing skin wound healing: a review of current practice

The two-dimensional nanomaterials are characterized by their ultra-thin structure, diverse chemical functional groups, and remarkable anisotropic properties. Since its discovery in 2004, graphene has attracted significant scientific interest due to its potential applications in various fields, including electronics, energy systems, and biomedicine. In medicine, graphene is used for designing smart drug delivery systems, especially for antibiotics, and biosensing. Skin trauma is a prevalent dermatological condition that increasingly contributes to morbidities and mortalities, thus representing a significant health burden. During tissue damage, rapid skin repair is crucial to prevent blood loss and infection. Therefore, drugs used for skin trauma must possess antimicrobial and anti-inflammatory properties. Two-dimensional (2D) nanomaterials possess remarkable physical, chemical, optical, and biological characteristics due to their uniform shape, increased surface area, and surface charge. Graphene and its derivatives, transition-metal dichalcogenides (TMDs), black phosphorous (BP), hexagonal boron nitride (h-BN), MXene, and metal-organic frameworks (MOFs) are among the commonly used 2D nanomaterials. Moreover, they exhibit antibacterial and anti-inflammatory properties. This review presents a comprehensive discussion of the clinical approaches employed for wound healing treatment and explores the applications of commonly used 2D nanomaterials to enhance wound healing outcomes.

Enhancing Wound Healing: A Comprehensive Review of Sericin and Chelidonium majus L. as Potential Dressings

Wound healing, a complex physiological process orchestrating intricate cellular and molecular events, seeks to restore tissue integrity. The burgeoning interest in leveraging the therapeutic potential of natural substances for advanced wound dressings is a recent phenomenon. Notably, Sericin, a silk-derived protein, and Chelidonium majus L. (C. majus), a botanical agent, have emerged as compelling candidates, providing a unique combination of natural elements that may revolutionize conventional wound care approaches. Sericin, renowned for its diverse properties, displays unique properties that accelerate the wound healing process. Simultaneously, C. majus, with its diverse pharmacological compounds, shows promise in reducing inflammation and promoting tissue regeneration. As the demand for innovative wound care solutions increases, understanding the therapeutic potential of natural products becomes imperative. This review synthesizes current knowledge on Sericin and C. majus, envisioning their future roles in advancing wound management strategies. The exploration of these natural substances as constituents of wound dressings provides a promising avenue for developing sustainable, effective, and biocompatible materials that could significantly impact the field of wound healing.

Chitosan based extruded nanofibrous bioscaffold for local delivery of mesenchymal stem cells to improve diabetic wound healing

BACKGROUND

Mesenchymal stem cells (MSCs)-based treatment strategy has shown promise in bolstering the healing process of chronic wounds in diabetic patients, who are at risk of amputation and mortality. To overcome the drawbacks of suboptimal cell retention and diminished cell viability at the injury site, a novel nanofibrous biomaterial-based scaffold was developed by using a controlled extrusion of a polymeric solution to deliver the cells (human adipose-derived MSCs (ADMSCs) and placenta-derived MSCs (PLMSCs)) locally to the animal model of diabetic ulcers.

METHODS

The physicochemical and biological properties of the nano-bioscaffold were characterized in terms of microscopic images, FTIR spectroscopy, tensile testing, degradation and swelling tests, contact angle measurements, MTT assay, and cell attachment evaluation. To evaluate the therapeutic efficacy, a study using an excisional wound model was conducted on diabetic rats.

RESULTS

The SEM and AFM images of scaffolds revealed a network of uniform nanofibers with narrow diameters between 100-130 nm and surface roughness less than 5 nm, respectively. ADMSCs and PLMSCs had a typical spindle-shaped or fibroblast-like morphology when attached to the scaffold. Desired characteristics in terms of swelling, hydrophilicity, biodegradation rate, and biocompatibility were achieved with the CS70 formulation. The wound healing process was accelerated according to wound closure rate assay upon treatment with MSCs loaded scaffold resulting in increased re-epithelialization, neovascularization, and less inflammatory reaction. Our findings unequivocally demonstrated that the cell-loaded nano-bioscaffold exhibited more efficacy compared with its acellular counterpart. In summation, our study underscores the potential of this innovative cellular scaffold as a viable solution for enhancing the healing of diabetic ulcers.

CONCLUSION

The utilization of MSCs in a nanofibrous biomaterial framework demonstrates significant promise, providing a novel avenue for advancing wound care and diabetic ulcer management.

Exploring the underlying pharmacological, immunomodulatory, and anti-inflammatory mechanisms of phytochemicals against wounds: a molecular insight

BACKGROUND

Numerous cellular, humoral, and molecular processes are involved in the intricate process of wound healing.

PHARMACOLOGICAL RELEVANCE

Numerous bioactive substances, such as ß-sitosterol, tannic acid, gallic acid, protocatechuic acid, quercetin, ellagic acid, and pyrogallol, along with their pharmacokinetics and bioavailability, have been reviewed. These phytochemicals work together to promote angiogenesis, granulation, collagen synthesis, oxidative balance, extracellular matrix (ECM) formation, cell migration, proliferation, differentiation, and re-epithelialization during wound healing.

FINDINGS AND NOVELTY

To improve wound contraction, this review delves into how the application of each bioactive molecule mediates with the inflammatory, proliferative, and remodeling phases of wound healing to speed up the process. This review also reveals the underlying mechanisms of the phytochemicals against different stages of wound healing along with the differentiation of the in vitro evidence from the in vivo evidence There is growing interest in phytochemicals, or plant-derived compounds, due their potential health benefits. This calls for more scientific analysis and mechanistic research. The various pathways that these phytochemicals control/modulate to improve skin regeneration and wound healing are also briefly reviewed. The current review also elaborates the immunomodulatory modes of action of different phytochemicals during wound repair.

Ethnomedical Knowledge of Plants Used in Nonconventional Medicine for Wound Healing in Lubumbashi, Haut-Katanga Province, DR Congo

Medicinal plants used for wound healing in Lubumbashi have yet to be discovered. Inventory or profile of their taxa has yet to be established. The present study was carried out to survey the plants used in traditional medicine in Lubumbashi to treat wounds and to define their ethnomedical characteristics. The study was conducted between March 2021 and August 2022, using semistructured interview surveys of households (n = 2730), herbalists (n = 48), and traditional practitioners: TPs (n = 128).The 2,906 interviewed (sex ratio M/F = 0.9; mean age: 56 ± 3 years; and experience: 17 ± 4 years) provided information on 166 taxa, 130 used against chronic wounds, among which Securidaca longepedunculata was the top cited. Most of these taxa are shrubs (33%), belonging to 48 botanical families dominated by the Fabaceae (16%). They are indicated in 70 other pathologies. From these 166 taxa, 198 healing recipes are obtained, 11 combining more than one plant. In all these recipes, the leaf (>36%) is the most used part, and the poultice (>36%) is the most popular form of use. Twelve taxa are cited for the first time as medicinal plants, of which Agelanthus zizyphifolius has the highest consensus and Erigeron sumatrensis has the highest usual value. For the various plants used to treat wounds, some of which are specific to the region, further studies should focus on validating this traditional use.

Magneto-responsive biocomposites in wound healing: from characteristics to functions

The number of patients with non-healing wounds continuously increases, and has become a prominent societal issue that imposes a heavy burden on both patients and the entire healthcare system. Although traditional dressings play an important role in wound healing, the complexity and diversity of the healing process pose serious challenges in this field. Magneto-responsive biocomposites, with their excellent biocompatibility, remote spatiotemporal controllability, and unique convenience, demonstrate enticing advantages in the field of wound dressings. However, current research on magneto-responsive biocomposites as wound dressings lacks comprehensive and in-depth reviews, which to some extent, restricts the deeper understanding and further development of this field. Based on this, this paper reviews the latest advances in magnetic responsive wound dressings for wound healing. First, we review the process of skin wound healing and parameters for assessing repair progress. Then, we systematically discuss the preparation strategies and unique characteristics of magneto-responsive biocomposites, focusing on magneto-induced orientation, magneto-induced mechanical stimulation, and magnetocaloric effect. Subsequently, this review elaborates the multiple mechanisms of magneto-responsive biocomposites in promoting wound healing, including regulating cell behavior, enhancing electrical signal, controlling drug release, and accelerating tissue reconstruction. Finally, we further propose the development direction and future challenges of magnetic responsive biomaterials as wound dressings in clinical application.

Towards the development of sensation-enabled skin substitutes

Recent advances in cell and biofabrication technologies have contributed to the development of complex human organs. In particular, several skin substitutes are being generated using tissue engineering and regenerative medicine (TERM) technologies. However, recent studies mainly focus on the restoration of the dermis and epidermis layers rather than the regeneration of a fully functional innervated skin organ. Innervation is a critical step in functional tissue repair which has been overlooked in the current TERM studies. In the current study, we highlight the importance of sensation in the skin as the largest sensory organ in the human body. In large non-healing skin wounds, the skin sensation is severely diminished or completely lost and ultimately lead to chronic pain and wound healing process interruption. Current therapeutics for restoring skin sensation after trauma are limited. Recent regenerative medicine-based studies could successfully induce neural networks in skin substitutes, but the effectiveness of these technologies in enhancing sensory capability needs further investigation.

Spincare System Demonstrates Safety and Efficacy in Treating Partial-Thickness Burns

Partial-thickness burns are the most common form of burns, affecting the dermis and possibly resulting in scarring and infection. The Spincare System is a new device that uses electrospinning technology to create a temporary skin-like matrix that can be applied to wounds. This study evaluated the performance, safety, and efficacy of Spincare in treating superficial to partial-thickness burns not considered for surgery. A prospective single-arm, open-label, multicenter study was conducted in 3 adult burn units across Israel. Forty-four patients with superficial to intermediate burns of up to 10% of TBSA were enrolled. Spincare was applied to the wounds, and follow-up visits were performed on days 7, 14, and 21 and months 3 and 6 posttreatment. Thirty-one patients with 36 wounds completed the day 21 visit. The mean wound healing area on day 21 was 97.26 ± 9.41%, and the mean healing time was 12.8 ± 4.3 days. Only one moderate adverse event was observed concerning the treatment, and it is important to acknowledge the potential progression of this hypertrophic scar into a keloid. This study demonstrated that Spincare is a safe and effective device for treating superficial to intermediate partial-thickness burns. Spincare achieved rapid and complete wound healing with a low incidence of adverse events.

Development and characterization of three-dimensional antibacterial nanocomposite sponges of chitosan, silver nanoparticles and halloysite nanotubes

In this work, we developed novel nanocomposite three-dimensional (3D) scaffolds composed of chitosan (CTS), halloysite nanotubes (HNTs) and silver nanoparticles (AgNPs) with enhanced antimicrobial activity and fibroblast cell compatibility for their potential use in wound dressing applications. A stock CTS-HNT solution was obtained by mixing water-dispersed HNTs with CTS aqueous-acid solution, and then, AgNPs, in different concentrations, were synthesized in the CTS-HNT solution via a CTS-mediated in situ reduction method. Finally, freeze-gelation was used to obtain CTS-HNT-AgNP 3D porous scaffolds (sponges). Morphology analysis showed that synthesized AgNPs were spherical with an average diameter of 11 nm. HNTs' presence did not affect the AgNPs morphology or size but improved the mechanical properties of the scaffolds, where CTS-HNT sponges exhibited a 5 times larger compression stress than bare-CTS sponges. AgNPs in the scaffolds further increased their mechanical strength in correlation to the AgNP concentration, and conferred them improved antibacterial activity against Gram-negative and Gram-positive bacteria, inhibiting the planktonic proliferation and adhesion of bacteria in a AgNP concentration depending on manner. In vitro cell viability and immunofluorescence assays exhibited that human fibroblast (HF) culture was supported by the sponges, where HF retained their phenotype upon culture on the sponges. Present CTS-HNT-AgNP sponges showed promising mechanical, antibacterial and cytocompatibility properties to be used as potential scaffolds for wound dressing applications.

An Investigation into the Phytochemical Content and Antioxidant, Antidiabetic, and Wound-Healing Activities of Curculigo latifolia Found in Brunei Darussalam

This present study aimed to investigate the phytochemical content and antioxidant and antidiabetic activities of Curculigo latifolia leaves (CL) and C. latifolia roots (CR) found in Brunei Darussalam. Phytochemical screening showed that CL and CR extracts contain saponins, tannins, glycosides, and terpenoids. CR showed higher total phenolic content (TPC), but lower total flavonoid content (TFC) when compared to CL. The high TPC in CR contributed to its potent radical scavenging activity (RSA) against 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals and strong ferric reducing antioxidant power (FRAP). Additionally, CR exerted significant inhibition of ∝-glucosidase and ∝-amylase, suggesting a potential link between the chemical compounds and its antioxidant and antidiabetic effects. In the animal study of antihyperglycemic activity, treatment with 250 mg/kg body weight (b.w.) of the CL extract normalised the blood glucose levels and improved body weight gain of alloxan-induced diabetic rats within 14 weeks. Furthermore, our investigation into the wound-healing effects of young C. latifolia leaves (YCL) and matured C. latifolia leaves (MCL) showed a significant reduction in wound size on Day 3, 5, and 7 of the experimental study, indicating its wound-healing potential. Based on our findings, C. latifolia can be consumed as part of a balanced diet due to its antioxidant and antidiabetic properties.

Evaluation of viscoelastic parameters and photo-based assessment of newly developed dermal substitutes modified with thermostabilized fibroblast growth factor 2

BACKGROUND

The purpose of dermal substitutes is to mimic the basic properties of the extracellular matrix of human skin. The application of dermal substitutes to the defect reduces the formation of hypertrophic scars and improves the scar quality. This study aims to develop an original dermal substitute enriched with stable fibroblast growth factor 2 (FGF2-STAB®) and test it in an animal model.

METHODS

Dermal substitutes based on collagen/chitosan scaffolds or collagen/chitosan scaffolds with nanofibrous layer were prepared and enriched with FGF2-STAB® at concentrations of 0, 0.1, 1.0, and 10.0 µg ‧ cm-2. The performance of these dermal substitutes was tested in vivo on artificially formed skin defects in female swine. The outcomes were evaluated using cutometry at 3 and 6 months. In addition, visual appearance was assessed based on photos of the scars at 1-month, 3-month and 6-month follow-ups using Yeong scale and Visual Analog Scale.

RESULTS

The dermal substitute was fully integrated into all defects and all wounds healed successfully. FGF2-STAB®-enriched matrices yielded better results in cutometry compared to scaffolds without FGF2. Visual evaluation at 1, 3, and 6 months follow-ups detected no significant differences among groups. The FGF2-STAB® effectiveness in improving the elasticity of scar tissues was confirmed in the swine model. This effect was independently observed in the scaffolds with nanofibres as well as in the scaffolds without nanofibres.

CONCLUSION

The formation of scars with the best elasticity was exhibited by addition 1.0 µg ‧ cm-2of FGF2-STAB® into the scaffolds, although it had no significant effect on visual appearance at longer follow-ups. This study creates the basis for further translational studies of the developed product and its progression into the clinical phase of the research.

Films based on TEMPO-oxidized chitosan nanoparticles: Obtaining and potential application as wound dressings

A series of novel films based on TEMPO-oxidized chitosan nanoparticles were prepared by casting method. Fourier transform infrared spectroscopy (FTIR) was employed to ascertain the chemical structure of TEMPO-oxidized chitosan. The surface morphology of the TEMPO-oxidized chitosan nanoparticles was analyzed by atomic force microscopy (AFM). The physicochemical (area density, thickness, iodine sorption, roughness), functional (moisture sorption, liquid absorption capacity, weight loss upon contact with the liquid, and water vapor transmission rate), antibacterial, and antioxidant properties of films based on TEMPO-oxidized chitosan nanoparticles were also investigated. The physicochemical properties of the films varied widely: area density ranged from 77.83 ± 0.06 to184.46 ± 0.05 mg/cm2, thickness varied between 80.5 ± 1.6 and 200.5 ± 1.6 μm, iodine sorption spanned from 333.7 ± 2.1 to166.4 ± 2.2 mg I2/g, and roughness ranged from 4.1 ± 0.2 to 5.6 ± 0.3 nm. Similarly, the functional properties also varied significantly: moisture sorption ranged from 4.76 ± 0.03 to 9.62 ± 0.11 %, liquid absorption capacity was between 129.04 ± 0.24 and 159.33 ± 0.73 % after 24 h, weight loss upon contact with the liquid varied between 31.06 ± 0.35 and 45.88 ± 0.58 % after 24 h and water vapor transmission rate ranged from 1220.10 ± 2.91to1407.77 ± 5.22 g/m2 day. Despite the wide variations in physicochemical and functional properties, all films showed maximum bacterial reduction of Staphylococcus aureus and Escherichia coli, although they exhibited low antioxidant activity. The results suggest that the films could be effectively utilized as antibacterial wound dressings.

Bone marrow derived mesenchymal stem cells enriched PCL-gelatin nanofiber scaffold for improved wound healing

Electrospun nanofibers exhibit a significant potential in the synthesis of nanostructured materials, thereby offering a promising avenue for enhancing the efficacy of wound care. The present study aimed to investigate the wound-healing potential of two biomacromolecules, PCL-Gelatin nanofiber adhered with bone marrow-derived mesenchymal stem cells (BMSCs). Characterisation of the nanofiber revealed a mean fiber diameter ranging from 200 to 300 nm, with distinctive elemental peaks corresponding to polycaprolactone (PCL) and gelatin. Additionally, BMSCs derived from bone marrow were integrated into nanofibers, and their wound-regenerative potential was systematically evaluated through both in-vitro and in-vivo methodologies. In-vitro assessments substantiated that BMSC-incorporated nanofibers enhanced cell viability and crucial cellular processes such as adhesion, and proliferation. Subsequently, in-vivo studies were performed to demonstrate the wound-healing efficacy of nanofibers. It was observed that the rate of wound healing of BMSCs incorporated nanofibers surpassed both, nanofiber and BMSCs alone. Furthermore, histomorphological analysis revealed accelerated re-epithelization and improved wound contraction in BMSCs incorporated nanofiber group. The fabricated nanofiber incorporated with BMSCs exhibited superior wound regeneration in animal model and may be utilised as a wound healing patch.

A Highly Standardized Pre-Clinical Porcine Wound Healing Model Powered by Semi-Automated Histological Analysis

The wound-healing process is a physiological response that begins after a disruption to the integrity of tissues present in the skin. To understand the intricacies involved in this process, many groups have tried to develop different in vitro models; however, the lack of a systemic response has, until this day, been the major barrier to the establishment of these models as the main study platform. Therefore, in vivo models are still the most common system for studying healing responses following different treatments, especially porcine models, which share several morphological similarities to the human skin. In this work, we developed a porcine excisional wound model and used semi-automated software as a strategy to generate quantitative morphometric results of healing responses by specific tissues and compartments. Our aim was to extract the most information from the model while producing reliable, reproducible, and standardized results. In order to achieve this, we established a 7-day treatment using a bacterial cellulose dressing as our standard for all the analyzed wounds. The thickness of the residual dermis under the wound (DUtW) bed was shown to influence the healing outcome, especially for the regeneration of epidermal tissue, including the wound closure rate. The analysis of the DUtW throughout the entire dorsal region of the animals opened up the possibility of establishing a map that will facilitate the experimental design of future works, increasing their standardization and reproducibility and ultimately reducing the number of animals needed. Thus, the developed model, together with the automated morphometric analysis approach used, offers the possibility to generate robust quantitative results with a rapid turnaround time while allowing the study of multiple extra morphometric parameters, creating a more holistic analysis.

Radiation Induced Skin Fibrosis (RISF): Opportunity for Angiotensin II-Dependent Intervention

Medical procedures, such as radiation therapy, are a vital element in treating many cancers, significantly contributing to improved survival rates. However, a common long-term complication of such exposure is radiation-induced skin fibrosis (RISF), a complex condition that poses substantial physical and psychological challenges. Notably, about 50% of patients undergoing radiation therapy may achieve long-term remission, resulting in a significant number of survivors managing the aftereffects of their treatment. This article delves into the intricate relationship between RISF, reactive oxygen species (ROS), and angiotensin II (Ang II) signaling. It proposes the underlying mechanisms and examines potential treatments for mitigating skin fibrosis. The primary goal is to offer essential insights in order to better care for and improve the quality of life of cancer survivors who face the risk of developing RISF.

Kynurenines as a Novel Target for the Treatment of Inflammatory Disorders

This review discusses the potential of targeting the kynurenine pathway (KP) in the treatment of inflammatory diseases. The KP, responsible for the catabolism of the amino acid tryptophan (TRP), produces metabolites that regulate various physiological processes, including inflammation, cell cycle, and neurotransmission. These metabolites, although necessary to maintain immune balance, may accumulate excessively during inflammation, leading to systemic disorders. Key KP enzymes such as indoleamine 2,3-dioxygenase 1 (IDO1), indoleamine 2,3-dioxygenase 2 (IDO2), tryptophan 2,3-dioxygenase (TDO), and kynurenine 3-monooxygenase (KMO) have been considered promising therapeutic targets. It was highlighted that both inhibition and activation of these enzymes may be beneficial, depending on the specific inflammatory disorder. Several inflammatory conditions, including autoimmune diseases, for which modulation of KP activity holds therapeutic promise, have been described in detail. Preclinical studies suggest that this modulation may be an effective treatment strategy for diseases for which treatment options are currently limited. Taken together, this review highlights the importance of further research on the clinical application of KP enzyme modulation in the development of new therapeutic strategies for inflammatory diseases.

3D Porous Polymer Scaffold-Conjugated KGF-Mimetic Peptide Promotes Functional Skin Regeneration in Chronic Diabetic Wounds

The re-epithelialization process gets severely dysregulated in chronic nonhealing diabetic foot ulcers/wounds. Keratinocyte growth factor (KGF or FGF-7) is the major modulator of the re-epithelialization process, which regulates the physiological phenotypes of cutaneous keratinocytes. The existing therapeutic strategies of growth factor administration have several limitations. To overcome these, we have designed a KGF-mimetic peptide (KGFp, 13mer) based on the receptor interaction sites in murine KGF. KGFp enhanced migration and transdifferentiation of mouse bone marrow-derived MSCs toward keratinocyte-like cells (KLCs). A significant increase in the expression of skin-specific markers Bnc1 (28.5-fold), Ck5 (14.6-fold), Ck14 (26.1-fold), Ck10 (187.7-fold), and epithelial markers EpCam (23.3-fold) and Cdh1 (64.2-fold) was associated with the activation of ERK1/2 and STAT3 molecular signaling in the KLCs. Further, to enhance the stability of KGFp in the wound microenvironment, it was conjugated to biocompatible 3D porous polymer scaffolds without compromising its active binding sites followed by chemical characterization using Fourier transform infrared spectroscopy, field-emission scanning electron microscopy, dynamic mechanical analysis, and thermogravimetry. In vitro evaluation of the KGFp-conjugated 3D polymer scaffolds revealed its potential for transdifferentiation of MSCs into KLCs. Transplantation of allogeneic MSCGFP using KGFp-conjugated 3D polymer scaffolds in chronic nonhealing type 2 diabetic wounds (db/db transgenic, 50-52 weeks old male mice) significantly enhanced re-epithelialization-mediated wound closure rate (79.3%) as compared to the control groups (Untransplanted -22.4%, MSCGFP-3D polymer scaffold -38.5%). Thus, KGFp-conjugated 3D porous polymer scaffolds drive the fate of the MSCs toward keratinocytes that may serve as potential stem cell delivery platform technology for tissue engineering and transplantation.

A New Nanoplatform Under NIR Released ROS Enhanced Photodynamic Therapy and Low Temperature Photothermal Therapy for Antibacterial and Wound Repair

Purpose

Skin injury, often caused by physical or medical mishaps, presents a significant challenge as wound healing is critical to restore skin integrity and tissue function. However, external factors such as infection and inflammation can hinder wound healing, highlighting the importance of developing biomaterials with antibiotic and wound healing properties to treat infections and inflammation. In this study, a novel photothermal nanomaterial (MMPI) was synthesized for infected wound healing by loading indocyanine green (ICG) on magnesium-incorporated mesoporous bioactive glass (Mg-MBG) and coating its surface with polydopamine (PDA).

Results

In this study, Mg-MBG and MMPI was synthesized via the sol-gel method and characterized it using various techniques such as scanning electron microscopy (SEM), the energy dispersive X-ray spectrometry (EDS) system and X-ray diffraction (XRD). The cytocompatibility of MMPI was evaluated by confocal laser scanning microscopy (CLSM), CCK8 assay, live/dead staining and F-actin staining of the cytoskeleton. The antibacterial efficiency was assessed using bacterial dead-acting staining, spread plate method (SPM) and TEM. The impact of MMPI on macrophage polarization was initially evaluated through flow cytometry, qPCR and ELISA. Additionally, an in vivo experiment was performed on a mouse model with skin excision infected. Histological analysis and RNA-seq analysis were utilized to analyze the in vivo wound healing and immunomodulation effect.

Conclusion

Collectively, the new photothermal and photodynamic nanomaterial (MMPI) can achieve low-temperature antibacterial activity while accelerating wound healing, holds broad application prospects.

Natural Compounds for Preventing Age-Related Diseases and Cancers

Aging is a multifaceted process influenced by hereditary factors, lifestyle, and environmental elements. As time progresses, the human body experiences degenerative changes in major functions. The external and internal signs of aging manifest in various ways, including skin dryness, wrinkles, musculoskeletal disorders, cardiovascular diseases, diabetes, neurodegenerative disorders, and cancer. Additionally, cancer, like aging, is a complex disease that arises from the accumulation of various genetic and epigenetic alterations. Circadian clock dysregulation has recently been identified as an important risk factor for aging and cancer development. Natural compounds and herbal medicines have gained significant attention for their potential in preventing age-related diseases and inhibiting cancer progression. These compounds demonstrate antioxidant, anti-inflammatory, anti-proliferative, pro-apoptotic, anti-metastatic, and anti-angiogenic effects as well as circadian clock regulation. This review explores age-related diseases, cancers, and the potential of specific natural compounds in targeting the key features of these conditions.

Exploring the mechanistic role of silk sericin biological and chemical conjugates for effective acute and chronic wound repair and related complications

OBJECTIVE

The current review is designed to elaborate and reveal the underlying mechanism of sericin and its conjugates of drug delivery during wounds and wound-related issues.

SIGNIFICANCE

Wound healing is a combination of different humoral, molecular, and cellular mechanisms. Various natural products exhibit potential in wound healing but among them, sericin, catches much attention of researchers due to its bio-functional properties such as being biodegradable, biocompatible, anti-oxidant, anti-bacterial, photo-protector, anti-inflammatory and moisturizing agent.

METHODS AND RESULTS

Sericin triggers the activity of anti-inflammatory cytokines which decrease cell adhesion and promote epithelial cell formation. Moreover, sericin enhances the anti-oxidant enzymes in the wounded area which scavenge the toxic consequences of reactive species (ROS).

CONCLUSIONS

This article highlights the mechanisms of how topical administration of sericin formulations along with 4-hexylresorcinol,\Chitosan\Ag@MOF-GO, polyvinyl alcohol (PVA), platelet lysate and UV photo cross-linked hydrogel sericin methacrylate which recruits a large number of cytokines on wounded area that stimulate fibroblasts and keratinocyte production as well as collagen deposition that led to early wound contraction. It also reviews the different sericin-based nanoparticles that play a significant role in rapid wound healing.