Pathophysiology of acute wound healing

Antivirulence and antipathogenic activity of Mayan herbal remedies against Pseudomonas aeruginosa

ETHNOPHARMACOLOGICAL RELEVANCE

The Yucatan Peninsula has a privileged wealth of vascular plants with which various Mayan herbal formulations have been developed. However, studies on their antipathogenic and antivirulence properties are scarce.

AIM OF THE STUDY

Identify antivirulence properties in Mayan herbal remedies and determine their antipathogenic capacity in burn wounds infected with Pseudomonas aeruginosa.

MATERIALS AND METHODS

An ethnobotanical study was conducted in Mayan communities in central and southern Quintana Roo, Mexico. Furthermore, the antipathogenic capacity of three Mayan herbal remedies was analyzed using an animal model of thermal damage and P. aeruginosa infection. Antivirulence properties were determined by inhibiting phenotypes regulated by quorum sensing (pyocyanin, biofilm, and swarming) and by the secretion of the ExoU toxin. The chemical composition of the most active herbal remedy was analyzed using molecular network analysis.

RESULTS

It was found that topical administration of the remedy called "herbal soap" (HS) for eleven days maintained 100% survival of the animals, reduced establishment of the bacteria in the burn and prevented its systemic dispersion. Although no curative effect was recorded on tissue damaged by HS treatment, its herbal composition strongly reduced swarming and ExoU secretion. Through analysis of Molecular Networks, it was possible to carry out a global study of its chemical components, and identify the family of oxindole monoterpenoid alkaloids and carboline and tetrahydropyrididole alkaloids. In addition, flavonols, flavan-3-ols, and quinic acid derivatives were detected.

CONCLUSIONS

The antipathogenic and antivirulence capacity of ancient Mayan remedies makes them a potential resource for developing new antibacterial therapies to treat burns infected by P. aeruginosa.

The Potential Role of Cannabidiol in Cosmetic Dermatology: A Literature Review

Cannabidiol (CBD) is a non-psychotropic cannabinoid with multiple pharmacological properties. Cannabidiol has attracted growing attention in the cosmetic industry, with an increasing number of CBD-containing skincare products on the market in recent years. The aim of this review is to evaluate the current evidence on the use of CBD for cosmetic purposes. Following an overview of CBD and the endocannabinoid system in the skin, we summarize pre-clinical and clinical studies that address the potential of CBD in cosmetic dermatology. Available in vitro and in vivo evidence suggests that CBD has anti-oxidant, anti-inflammatory, moisturizing, anti-acne, wound-healing, and anti-aging properties. However, only a few clinical studies have been conducted on the use of CBD in the skin. In addition, there is a critical need to develop an efficient drug-delivery system for topical/transdermal application of CBD. Further research, including clinical and pharmacokinetic studies, are needed to fully evaluate the role of CBD in cosmetic dermatology.

Advances in ionic liquid-based antimicrobial wound healing platforms

Wound infections, marked by the proliferation of microorganisms at surgical sites, necessitate the development of innovative wound dressings with potent bactericidal properties to curb microbial growth and prevent bacterial infiltration. This study explores the recent strides in utilizing ionic liquid-based polymers as highly promising antimicrobial agents for advanced wound healing applications. Specifically, cationic polymers containing quaternary ammonium, imidazolium, guanidinium, pyridinium, triazolium, or phosphonium groups have emerged as exceptionally effective antimicrobial compounds. Their mechanism of action involves disrupting bacterial membranes, thereby preventing the development of resistance and minimizing toxicity to mammalian cells. This comprehensive review not only elucidates the intricate dynamics of the skin's immune response and the various stages of wound healing but also delves into the synthesis methodologies of ionic liquid-based polymers. By spotlighting the practical applications of antimicrobial wound dressings, particularly those incorporating ionic liquid-based materials, this review aims to lay the groundwork for future research endeavors in this burgeoning field. Through a nuanced examination of these advancements, this article seeks to contribute to the ongoing progress in developing cutting-edge wound healing platforms that can effectively address the challenges posed by microbial infections in surgical wounds.

Explicating the multifunctional roles of tocotrienol and squalene in promoting skin health

The skin is the largest organ in the integumentary system, protecting against various external threats, including ultraviolet exposure, heat, infections, dehydration and mechanical injuries. Skin disorders can arise from various causes, including allergic reactions or breaches in the skin barrier, which allow microorganisms or chemicals to penetrate the sweat ducts. These conditions encompass a wide range of issues, including acne, xerosis (dry skin), fungal infections, atopic dermatitis (eczema) and psoriasis. Collectively, these ailments affect a significant portion of the global population, impacting approximately one-third of people worldwide. Additionally, oxidative stress induced by ageing and prolonged exposure to ultraviolet rays can manifest in visible alterations such as pigmentation, wrinkling and dehydration. Recent investigations have underscored the potential of natural antioxidant compounds in safeguarding skin health and combating ageing-related changes. Tocotrienols, a subgroup of vitamin E, have garnered significant attention owing to their antioxidant and anti-inflammatory properties. Significant amounts of tocotrienols can be found in rice bran, olive, oats and hazelnuts. Similarly, squalene, predominantly sourced from fish liver oils such as those from sharks, has been used as an emollient in cosmetic formulations. This article offers a comprehensive review of existing literature elucidating the dermatological benefits associated with tocotrienols and squalene, emphasising their roles as antioxidants, anti-inflammatories, skin barrier protection and facilitators of wound healing. Moreover, it sheds light on contemporary research findings suggesting these compounds' therapeutic promise in managing and ameliorating various skin conditions.

Chitosan-based self-healing hydrogel dressing for wound healing

Skin has strong self-regenerative capacity, while severe skin defects do not heal without appropriate treatment. Therefore, in order to cover the wound sites and hasten the healing process, wound dressings are required. Hydrogels have emerged as one of the most promising candidates for wound dressings because of their hydrated and porous molecular structure. Chitosan (CS) with biocompatibility, oxygen permeability, hemostatic and antimicrobial properties is beneficial for wound treatment and it can generate self-healing hydrogels through reversible crosslinks, from dynamic covalent bonding, such as Schiff base bonds, boronate esters, and acylhydrazone bonds, to physical interactions like hydrogen bonding, electrostatic interaction, ionic bonding, metal-coordination, host-guest interactions, and hydrophobic interaction. Therefore, various chitosan-based self-healing hydrogel dressings have been prepared in recent years to cope with increasingly complex wound conditions. This review's objective is to provide comprehensive information on the self-healing mechanism of chitosan-based hydrogel wound dressings, discuss their advanced functions including antibacterial, conductive, anti-inflammatory, anti-oxidant, stimulus-responsive, hemostatic/adhesive and controlled release properties, further introduce their applications in the promotion of wound healing in two categories: acute and chronic (infected, burn and diabetic) wounds, and finally discuss the future perspective of chitosan-based self-healing hydrogel dressings for wound healing.

The interplay of skin architecture and cellular dynamics in wound healing: Insights and innovations in care strategies

Wound healing involves complex interactions among skin layers: the epidermis, which epithelializes to cover wounds; the dermis, which supports granulation tissue and collagen production; and the hypodermis, which protects overall skin structure. Key factors include neutrophils, activated by platelet degranulation and cytokines, and fibroblasts, which aid in collagen production during proliferation. The healing process encompasses inflammation, proliferation, and remodeling, with angiogenesis, fibroplasia, and re-epithelialization crucial for wound closure. Angiogenesis is characterized by the creation of collateral veins, the proliferation of endothelial cells, and the recruitment of perivascular cells. Collagen is produced by fibroblasts in granulation tissue, aiding in the contraction of wounds. The immunological response is impacted by T cells and cytokines. External topical application of various formulations and dressings expedites healing and controls microbial contamination. Polymeric materials, both natural and synthetic, and advanced dressings enhance healing by providing biodegradability, biocompatibility, and infection control, thus addressing tissue regeneration challenges. Numerous dressings promote healing, including films, hydrocolloids, hydrogels, foams, alginates, and tissue-engineered substitutes. Wound dressings are treated with growth factors, particularly PDGF, and antibacterial drugs to prevent infection. The challenges of tissue regeneration and infection control are evolving along with the field of wound care.

Melatonin and Bacterial Cellulose Regulate the Expression of Inflammatory Cytokines, VEGF, PCNA, and Collagen in Cutaneous Wound Healing in Diabetic Rats

The poor healing of diabetic wounds is characterized by prolonged inflammation and decreased collagen deposition. Diabetic patients exhibit changes in the plasma concentrations of pro-inflammatory cytokines, and the role of specific dressings may have an impact on healing. This study aims to evaluate the effects of a combined treatment comprising a bacterial cellulose dressing and melatonin application on the regulation and expression of inflammatory cytokines, VEGF, PCNA, and collagen in the healing of cutaneous wounds of diabetic rats. Pro-inflammatory cytokines, including IL-6, TNF-α, and VEGF, along with PCNA and type I and III collagen, were evaluated after 14 days. Immunohistochemistry showed decreased levels of IL-6, TNF-α, and VEGF, along with an increased expression of PCNA and type I collagen, in the groups treated exclusively with melatonin and bacterial cellulose associated with melatonin compared to the control and the commercial healing agent. It was concluded that treating the skin lesions of diabetic animals supplemented with melatonin using a bacterial cellulose-based dressing has positive effects in regulating the expression of inflammatory cytokines, vascular endothelial growth factor, and collagen, showing that this association could be a viable therapy approach in wound healing.

Insulin-Induced Gene 1-Enhance Secretion of BMSC Exosome Enriched in miR-132-3p Promoting Wound Healing in Diabetic Mice

Chronic diabetic wounds represent a significant clinical challenge because of impaired healing processes, which require innovative therapeutic strategies. This study explores the therapeutic efficacy of insulin-induced gene 1-induced bone marrow mesenchymal stem cell exosomes (Insig1-exos) in promoting wound healing in diabetic mice. We demonstrated that Insig1 enhanced the secretion of bone marrow mesenchymal stem cell-derived exosomes, which are enriched with miR-132-3p. Through a series of in vitro and in vivo experiments, these exosomes significantly promoted the proliferation, migration, and angiogenesis of dermal fibroblasts under high-glucose conditions. They also regulated key wound-healing factors, including matrix metalloproteinase-9, platelet-derived growth factor, vascular endothelial growth factor, transforming growth factor-β1, and platelet endothelial cell adhesion molecule-1, thereby accelerating wound closure in diabetic mice. Histological analysis showed that Insig1-exos were more effective in promoting epithelialization, enhancing collagen deposition, and reducing inflammation. Additionally, inhibition of miR-132-3p notably diminished these therapeutic effects, underscoring its pivotal role in the wound-healing mechanism facilitated by Insig1-exos. This study elucidates the molecular mechanisms through which Insig1-exos promotes diabetic wound healing, highlighting miR-132-3p as a key mediator. These findings provide new strategies and theoretical foundations for treating diabetes-related skin injuries.

Cellular and Molecular Effects of Magnetic Fields

Recently, magnetic fields (MFs) have received major attention due to their potential therapeutic applications and biological effects. This review provides a comprehensive analysis of the cellular and molecular impacts of MFs, with a focus on both in vitro and in vivo studies. We investigate the mechanisms by which MFs influence cell behavior, including modifications in gene expression, protein synthesis, and cellular signaling pathways. The interaction of MFs with cellular components such as ion channels, membranes, and the cytoskeleton is analyzed, along with their effects on cellular processes like proliferation, differentiation, and apoptosis. Molecular insights are offered into how MFs modulate oxidative stress and inflammatory responses, which are pivotal in various pathological conditions. Furthermore, we explore the therapeutic potential of MFs in regenerative medicine, cancer treatment, and neurodegenerative diseases. By synthesizing current findings, this article aims to elucidate the complex bioeffects of MFs, thereby facilitating their optimized application in medical and biotechnological fields.

Applications of mesenchymal stem cell-exosome components in wound infection healing: new insights

The healing process at a wound is made up of many types of cells, growth factors, the extracellular matrix, nerves and blood vessels all interacting with each other in complex and changing ways. Microbial colonization and proliferation are possible at the place of injury, which makes infection more likely. Because of this, any cut has a chance of getting an infection. Researchers have found that wound infections make patients more upset and cost the healthcare system a lot of money. Surgical site infections happen a lot to people who have recently had surgery. This study shows that such surgical infection is linked to a high rate of illness and death. This is shown by the fact that 25% of patients get serious sepsis and need to be transferred to an intensive care unit. In both animal models and people, mesenchymal stem cells (MSCs) play an active role in all stages of wound healing and have positive effects. Exosomes are one of the main things MSCs release. They have effects that are similar to those of the parent MSCs. Various effector proteins, messenger RNA and microRNAs can be transported by extracellular vesicles to control the activity of target cells. This has a big impact on the healing process. These results suggest that using MSC-exosomes as a new type of cell-free therapy could be a better and safer option than whole cell therapy. This review is mostly about how to use parts of MSC-exosomes to help wound infections heal.

Nanozyme-Incorporated Microneedles for the Treatment of Chronic Wounds

Acute wounds are converted to chronic wounds due to advanced age and diabetic complications. Nanozymes catalyze ROS production to kill bacteria without causing drug resistance, while microneedles (MNs) can break through the skin barrier to deliver drugs effectively. Nanozymes can be intergrateded into MNs delivery systems to improve painless drug delivery. It can also reduce the effective dose of drug sterilization while increasing delivery efficiency and effectively killing wounded bacteria while preventing drug resistance. This paper describes various types of metal nanozymes from previous studies and compares their mutual enhancement with nanozymes. The pooled results show that the MNs, through material innovation, are able to both penetrate the scab and deliver nanozymes and exert additional anti-inflammatory and bactericidal effects. The catalytic effect of some of the nanozymes can also accelerate the lysis of the MNs or create a cascade reaction against inflammation and infection. However, the issue of increased toxicity associated with skin penetration and clinical translation remains a challenge. This study reviews the latest published results and corresponding challenges associated with the use of MNs combined with nanozymes for the treatment of wounds, providing further information for future research.

The wound microbiota: microbial mechanisms of impaired wound healing and infection

The skin barrier protects the human body from invasion by exogenous and pathogenic microorganisms. A breach in this barrier exposes the underlying tissue to microbial contamination, which can lead to infection, delayed healing, and further loss of tissue and organ integrity. Delayed wound healing and chronic wounds are associated with comorbidities, including diabetes, advanced age, immunosuppression and autoimmune disease. The wound microbiota can influence each stage of the multi-factorial repair process and influence the likelihood of an infection. Pathogens that commonly infect wounds, such as Staphylococcus aureus and Pseudomonas aeruginosa, express specialized virulence factors that facilitate adherence and invasion. Biofilm formation and other polymicrobial interactions contribute to host immunity evasion and resistance to antimicrobial therapies. Anaerobic organisms, fungal and viral pathogens, and emerging drug-resistant microorganisms present unique challenges for diagnosis and therapy. In this Review, we explore the current understanding of how microorganisms present in wounds impact the process of skin repair and lead to infection through their actions on the host and the other microbial wound inhabitants.

Dynamic optical coherence tomography for imaging acute wound healing

The aim of this study was to investigate acute wound healing with dynamic optical coherence tomography (D-OCT). From 22 patients with 23 split skin graft donor sites, vessels at four wound edges, the wound bed, and adjacent and unaffected skin of the contralateral leg were measured by D-OCT at six time points from surgery to 4 weeks of healing. Changes in vessel orientation, density, diameter, morphology and pattern in horizontal, vertical and 3D images were analysed for wound healing and re-epithelialization. At 300 μm depth, there were significant differences of blobs and serpiginous vessels between normal and wounded skin. The wound had significantly more vertically oriented vessels, a higher degree of branching, vessel density and diameter compared with healthy skin. 3D images showed increased angiogenesis from healthy skin towards the wound centre, significantly higher vessel density at the wound than at normal skin and the highest at the interface. During wound healing blobs, coils and serpiginous vessels occurred significantly more frequently in lesional than healthy skin. Vessel density was greatest at the beginning, decreased and then increased by 4 weeks post-surgery. D-OCT helps to evaluate acute wound healing by visualizing and quantifying blood vessel growth in addition to re-epithelialization.

Potential Wound Healing and Anti-Melanogenic Activities in Skin Cells of Aralia elata (Miq.) Seem. Flower Essential Oil and Its Chemical Composition

Aralia elata (Miq.) Seem. (AES; family Araliaceae) is a medicinal plant and has been reported to have various bioactivities, including anticancer and hepatotoxicity protective activities. However, no studies have investigated the biological activities of AES or its extracts on skin. To address this, we aimed to explore the effect of AES-flower-derived absolute-type essential oil (AESFEO) on skin-related biological activities, especially skin wound healing and whitening-related responses in skin cells (human-derived keratinocytes [HaCaT cells] and melanocytes [B16BL6 cells]) and to identify the components of AESFEO. Cell biological activities were analyzed using WST and BrdU incorporation assays, ELISA, or by immunoblotting. In HaCaT cells, AESFEO promoted proliferation, type IV collagen production, and enhanced the phosphorylations of Erk1/2, p38 MAPK, JNK, and Akt. In B16BL6 cells, AESFEO reduced serum-induced proliferation, α-MSH-stimulated increases in melanin synthesis and tyrosinase activity, and α-MSH-induced increases in MITF, tyrosinase, TRP-1, and TRP-2 expressions. In addition, AESFEO inhibited the phosphorylation of Erk1/2, p38 MAPK, and JNK in α-MSH-stimulated B16BL6 cells. Eighteen compounds were identified in AESFEO by GC/MS. These results suggest that AESFEO has beneficial effects on keratinocyte activities related to skin wound healing and melanocyte activities related to inhibition of skin pigmentation. AESFEO may serve as a useful natural substance for developing agents that facilitate skin wound healing and inhibit melanogenesis.

Mangiferin Induces Post-Implant Osteointegration in Male Diabetic Rats

Background and Objectives: Hyperglycemia is known to undermine the osteointegration process of implants. In this study, the effects of mangiferin (MF) on the post-implant osteointegration process in a type-II diabetes model were investigated molecularly and morphologically. Materials and Methods: Sprague Dawley male rats were divided into three groups: control, diabetes, and diabetes + MF. All animals were implanted in their tibia bones on day 0. At the end of the 3-month experimental period, the animals' blood and the implant area were isolated. Biochemical measurements were performed on blood samples and micro-CT, qRT-PCR, histological, and immunohistochemical measurements were performed on tibia samples. Results: MF significantly improved the increased glucose, triglyceride-VLDL levels, and liver enzymes due to diabetes. By administering MF to diabetic rats, the osteointegration percentage and bone volume increased while porosity decreased. DKK1 and BMP-2 mRNA expressions and OPN, OCN, and OSN mRNA-protein expressions increased by MF administration in diabetic rats. Additionally, while osteoblast and osteoid surface areas increased with MF, osteoclast and eroded surface areas decreased. Conclusions: The findings of our study indicate that MF will be beneficial to the bone-repairing process and osteointegration, which are impaired by type-II diabetes.

Scholarly knowledge fundamentals and dynamic research hotspots in the field of burns and immunology: A bibliometric analysis

BACKGROUND

An estimated 180,000 burn deaths occur each year, and the immune system plays a vital role in wound healing and burn complications, including inflammatory reactions and oxidative stress. This paper aims to explore the basic knowledge and dynamic hotspots in burns and immunology research with bibliometric methods.

METHODS

Through systematic retrieval, we ensured all the documents complied with our retrieval strategy and were included in the Science Citation Index-Expanded of the Web of Science Core Collection. Using bibliometric methodologies, the general information was delineated; and foundational knowledge, as well as dynamic research hotspots, were ascertained through VOSviewer, CiteSpace, and R-bibliometrix.

RESULTS

8758 publications were identified from January 1st, 2000, to June 17th, 2024. The most productive and collaborative country was the USA; Harvard University was the most productive affiliation; and the most productive author was David N. Herndon. According to source analysis, the highest-impact journal is Burns. Historically, "expression" was the most frequently occurring word. "Delivery" was the most frequently occurring word in recent years.

CONCLUSION

The domain of burns and immunology has reached a zenith, with a modest decline in publication output over the past two years, yet it continues to evolve robustly. The focal points of inquiry have evolved from the initial appraisal of immunotherapeutic interventions for critical burn injuries to the elucidation of immune cell mechanisms in burn patients. Future research trajectory is poised to innovate therapeutic modalities, encompassing anti-inflammatory, antioxidant, and targeted drug delivery systems, to enhance precision in immune modulation.

Early postoperative water exposure does not increase complications in cutaneous surgeries: A randomized, investigator-blinded, controlled trial

BACKGROUND

Patients are often advised to keep the initial postoperative dressings dry and undisturbed for 24 to 72 hours. However, these requirements may result in significant disruption of patients' activities of daily living, such as bathing, leisure, and exercise.

OBJECTIVE

Compare standard management of keeping wounds dry and covered (48 hours) with early (6 hours) postoperative water exposure.

METHODS

Investigator-blinded, randomized (1:1), controlled trial evaluating rate of infection and additional outcomes of interest.

RESULTS

Overall, 437 patients were randomized to either the early (6-hour) water exposure (n = 218) intervention group or the standard cohort (n = 219). The incidence of culture-proven infection in the intervention group (1.8%) was similar to the standard group (1.4%) (P > .99). There was also no difference in rates of bleeding or bruising. Scar assessment using the Patient and Observer Scar Assessment Scale revealed similar scar outcomes.

LIMITATIONS

Single site, academic center.

CONCLUSION

Surgical wounds can be allowed to get wet in the immediate postoperative period with no increased incidence of infection or other complications and with similar cosmesis.

Management of Acute Wounds-Expert Panel Consensus Statement

Significance: The Wound Healing Foundation recognized the need for consensus-based unbiased recommendations for the treatment of wounds. As a first step, a consensus on the treatment of chronic wounds was developed and published in 2022. The current publication on acute wounds represents the second step in this process. Acute wounds may result from any number of conditions, including burns, military and combat operations, and trauma to specific areas of the body. The management of acute wounds requires timely and evidence-driven intervention to achieve optimal clinical outcomes. This consensus statement provides the clinician with the necessary foundational approaches to the causes, diagnosis, and therapeutic management of acute wounds. Presented in a structured format, this is a useful guide for clinicians and learners in all patient care settings. Recent Advances: Recent advances in the management of acute wounds have centered on stabilization and treatment in the military and combat environment. Specifically, advancements in hemostasis, resuscitation, and the mitigation of infection risk through timely initiation of antibiotics and avoidance of high-pressure irrigation in contaminated soft tissue injury. Critical Issues: Critical issues include infection control, pain management, and the unique considerations for the management of acute wounds in pediatric patients. Future Directions: Future directions include new approaches to preventing the progression and conversion of burns through the use of specific gel formulations. Additionally, the use of three-dimensional bioprinting and photo-modulation for reconstruction is a promising area for continued discovery.

Preclinical determination of wound-healing activity of halibut oil cream in rat model of burn wound

This study investigated the effects of halibut oil cream, containing omega-3 fatty acids, vitamins A and D, and hydroxyproline, on burn wound healing in rats. Acute dermal toxicity tests confirmed its nontoxicity. Wistar rats were divided into five groups: a control, a positive control treated with silver sulfadiazine 1% (SSD), and three groups treated with 3%, 9%, and 27% halibut oil cream Formulation (HBOF). The SSD and HBOF groups showed significant healing improvements compared to the control. Histopathological analysis indicated increased collagen production in the HBOF groups, suggesting halibut oil cream's potential as a topical treatment for burn wounds.

Silk Fibroin and Its Nanocomposites for Wound Care: A Comprehensive Review

For most individuals, wound healing is a highly organized, straightforward process, wherein the body transitions through different phases in a timely manner. However, there are instances where external intervention becomes necessary to support and facilitate different phases of the body's innate healing mechanism. Furthermore, in developing countries, the cost of the intervention significantly impacts access to treatment options as affordability becomes a determining factor. This is particularly true in cases of long-term wound treatment and management, such as chronic wounds and infections. Silk fibroin (SF) and its nanocomposites have emerged as promising biomaterials with potent wound-healing activity. Driven by this motivation, this Review presents a critical overview of the recent advancements in different aspects of wound care using SF and SF-based nanocomposites. In this context, we explore various formats of hemostats and assess their suitability for different bleeding situations. The subsequent sections discuss the primary causes of nonhealing wounds, i.e., prolonged inflammation and infections. Herein, different treatment strategies to achieve immunomodulatory and antibacterial properties in a wound dressing were reviewed. Despite exhibiting excellent pro-healing properties, few silk-based products reach the market. This Review concludes by highlighting the bottlenecks in translating silk-based products into the market and the prospects for the future.

Cell Migration Assays and Their Application to Wound Healing Assays-A Critical Review

In recent years, cell migration assays (CMAs) have emerged as a tool to study the migration of cells along with their physiological responses under various stimuli, including both mechanical and bio-chemical properties. CMAs are a generic system in that they support various biological applications, such as wound healing assays. In this paper, we review the development of the CMA in the context of its application to wound healing assays. As such, the wound healing assay will be used to derive the requirements on CMAs. This paper will provide a comprehensive and critical review of the development of CMAs along with their application to wound healing assays. One salient feature of our methodology in this paper is the application of the so-called design thinking; namely we define the requirements of CMAs first and then take them as a benchmark for various developments of CMAs in the literature. The state-of-the-art CMAs are compared with this benchmark to derive the knowledge and technological gap with CMAs in the literature. We will also discuss future research directions for the CMA together with its application to wound healing assays.

An Antibacterial, Conductive Nanocomposite Hydrogel Coupled with Electrical Stimulation for Accelerated Wound Healing

Background

Electrical stimulation (ES) can effectively promote skin wound healing; however, single-electrode-based ES strategies are difficult to cover the entire wound area, and the effectiveness of ES is often limited by the inconsistent mechanical properties of the electrode and wound tissue. The above factors may lead to ES treatment is not ideal.

Methods

A multifunctional conductive hydrogel dressing containing methacrylated gelatin (GelMA), Ti3C2 and collagen binding antimicrobial peptides (V-Os) was developed to improve wound management. Ti3C2 was selected as the electrode component due to its excellent electrical conductivity, the modified antimicrobial peptide V-Os could replace traditional antibiotics to suppress bacterial infections, and GelMA hydrogel was used due to its clinical applicability in wound healing.

Results

The results showed that this new hydrogel dressing (GelMA@Ti3C2/V-Os) not only has excellent electrical conductivity and biocompatibility but also has a durable and efficient bactericidal effect. The modified antimicrobial peptides V-Os used were able to bind more closely to GelMA hydrogel to exert long-lasting antibacterial effects. The results of cell experiment showed that the GelMA@Ti3C2/V-Os hydrogel dressing could enhance the effect of current stimulation and significantly improve the migration, proliferation and tissue repair related genes expression of fibroblasts. In vitro experiments results showed that under ES, GelMA@Ti3C2/V-Os hydrogel dressing could promote re-epithelialization, enhance angiogenesis, mediate immune response and prevent wound infection.

Conclusion

This multifunctional nanocomposite hydrogel could provide new strategies for promoting infectious wound healing.

Current Knowledge and Perspectives of Phage Therapy for Combating Refractory Wound Infections

Wound infection is one of the most important factors affecting wound healing, so its effective control is critical to promote the process of wound healing. However, with the increasing prevalence of multi-drug-resistant (MDR) bacterial strains, the prevention and treatment of wound infections are now more challenging, imposing heavy medical and financial burdens on patients. Furthermore, the diminishing effectiveness of conventional antimicrobials and the declining research on new antibiotics necessitate the urgent exploration of alternative treatments for wound infections. Recently, phage therapy has been revitalized as a promising strategy to address the challenges posed by bacterial infections in the era of antibiotic resistance. The use of phage therapy in treating infectious diseases has demonstrated positive results. This review provides an overview of the mechanisms, characteristics, and delivery methods of phage therapy for combating pathogenic bacteria. Then, we focus on the clinical application of various phage therapies in managing refractory wound infections, such as diabetic foot infections, as well as traumatic, surgical, and burn wound infections. Additionally, an analysis of the potential obstacles and challenges of phage therapy in clinical practice is presented, along with corresponding strategies for addressing these issues. This review serves to enhance our understanding of phage therapy and provides innovative avenues for addressing refractory infections in wound healing.

Human keratin matrices promote wound healing by modulating skin cell expression of cytokines and growth factors

A wide variety of biomaterials has been developed to assist in wound healing, including acellular animal and human-derived protein matrices. However, millions of patients worldwide still suffer from non-healing chronic wounds, demonstrating a need for further innovation in wound care. To address this need, a novel biomaterial, the human keratin matrix (HKM), was developed, characterised, and tested in vitro and in vivo. HKM was found to be degradation-resistant, and a proteomics analysis showed it to be greater than 99% human keratin proteins. PCR revealed adult human epidermal keratinocytes (HEKa) grown in contact with HKM showed increased gene expression of keratinocyte activations markers such as Epidermal Growth Factor (EGF). Additionally, a cytokine microarray demonstrated culture on HKM increased the release of cytokines involved in wound inflammatory modulation by both HEKa cells and adult human dermal fibroblasts (HDFa). Finally, in a murine chronic wound model, full-thickness wounds treated weekly with HKM were smaller through the healing process than those treated with human amniotic membrane (AM), bovine dermis (BD), or porcine decellularized small intestinal submucosa (SIS). HKM-treated wounds also closed significantly faster than AM- and SIS-treated wounds. These data suggest that HKM is an effective novel treatment for chronic wounds.

Plant-Derived Bioactive Compounds: Exploring Neuroprotective, Metabolic, and Hepatoprotective Effects for Health Promotion and Disease Prevention

There is a growing trend among consumers to seek out natural foods and products with natural ingredients. This shift in consumer preferences had a direct impact on both food and pharmaceutical industries, leading to a focus of scientific research and commercial efforts to meet these new demands. The aim of this work is to review recent available scientific data on foods of interest, such as the artichoke, gooseberry, and polygonoideae plants, as well as olive oil and red raspberries. Interestingly, the urgency of solutions to the climate change emergency has brought new attention to by-products of grapevine bunch stem and cane, which have been found to contain bioactive compounds with potential health benefits. There is a pressing need for a faster process of translating scientific knowledge from the laboratory to real-world applications, especially in the face of the increasing societal burden associated with non-communicable diseases (NCDs), environmental crises, the post-pandemic world, and ongoing violent conflicts around the world.

The Use of Extracellular Vesicles in Achilles Tendon Repair: A Systematic Review

Achilles tendon (AT) pathologies are common musculoskeletal conditions that can significantly impair function. Despite various traditional treatments, recovery is often slow and may not restore full functionality. The use of extracellular vesicles (EVs) has emerged as a promising therapeutic option due to their role in cell signaling and tissue regeneration. This systematic review aims to consolidate current in vivo animal study findings on the therapeutic effects of EVs on AT injuries. An extensive literature search was conducted using the PubMed, Scopus, and Embase databases for in vivo animal studies examining the effects of EVs on AT pathologies. The extracted variables included but were not limited to the study design, type of EVs used, administration methods, efficacy of treatment, and proposed therapeutic mechanisms. After screening, 18 studies comprising 800 subjects were included. All but one study reported that EVs augmented wound healing processes in the AT. The most proposed mechanisms through which this occurred were gene regulation of the extracellular matrix (ECM), the enhancement of macrophage polarization, and the delivery of therapeutic microRNAs to the injury site. Further research is warranted to not only explore the therapeutic potential of EVs in the context of AT pathologies, but also to establish protocols for their clinical application.

Bringing innovative wound care polymer materials to the market: Challenges, developments, and new trends

The development of innovative products for treating acute and chronic wounds has become a significant topic in healthcare, resulting in numerous products and innovations over time. The growing number of patients with comorbidities and chronic diseases, which may significantly alter, delay, or inhibit normal wound healing, has introduced considerable new challenges into the wound management scenario. Researchers in academia have quickly identified promising solutions, and many advanced wound healing materials have recently been designed; however, their successful translation to the market remains highly complex and unlikely without the contribution of industry experts. This review article condenses the main aspects of wound healing applications that will serve as a practical guide for researchers working in academia and industry devoted to designing, evaluating, validating, and translating polymer wound care materials to the market. The article highlights the current challenges in wound management, describes the state-of-the-art products already on the market and trending polymer materials, describes the regulation pathways for approval, discusses current wound healing models, and offers a perspective on new technologies that could soon reach consumers. We envision that this comprehensive review will significantly contribute to highlighting the importance of networking and exchanges between academia and healthcare companies. Only through the joint of these two actors, where innovation, manufacturing, regulatory insights, and financial resources act in harmony, can wound care products be developed efficiently to reach patients quickly and affordably.

Topographical depth reveals contact guidance mechanism distinct from focal adhesion confinement

Cellular response to the topography of their environment, known as contact guidance, is a crucial aspect to many biological processes yet remains poorly understood. A prevailing model to describe cellular contact guidance involves the lateral confinement of focal adhesions (FA) by topography as an underlying mechanism governing how cells can respond to topographical cues. However, it is not clear how this model is consistent with the well-documented depth-dependent contact guidance responses in the literature. To investigate this model, we fabricated a set of contact guidance chips with lateral dimensions capable of confining focal adhesions and relaxing that confinement at various depths. We find at the shallowest depth of 330 nm, the model of focal adhesion confinement is consistent with our observations. However, the cellular response at depths of 725 and 1000 nm is inadequately explained by this model. Instead, we observe a distinct reorganization of F-actin at greater depths in which topographically induced cell membrane deformation alters the structure of the cytoskeleton. These results are consistent with an alternative curvature-hypothesis to explain cellular response to topographical cues. Together, these results indicate a confluence of two molecular mechanisms operating at increased induced membrane curvature that govern how cells sense and respond to topography.

Tryptanthrin promotes pressure ulcers healing in mice by inhibiting macrophage-mediated inflammation via cGAS/STING pathways

BACKGROUND

Pressure ulcers (PUs) is ischemic necrosis caused by long-term local tissue pressure, directly affecting postoperative functional recovery. There is evidence that inflammation has an adverse impact on the development of PUs and contributes to unfavorable outcomes, suggesting that blocking the inflammatory response may be a promising therapeutic strategy for PUs. Tryptanthrin (Tryp), a natural product isolated from indigenous plants, has an anti-inflammatory biological function. However, the efficacy of Tryp in PUs remains unclear.

METHODS

Efficacy of Tryp suppressed inflammation was assessed using magnets-induced PUs model in mice. Hematoxylin-Eosin staining, masson staining and immunohistochemistry were used to evaluate the histologic changes after the formation of PUs. The expression of inflammatory cytokines was detected by qRT-PCR. And we detected the expression of protein by Western blotting.

RESULTS

Tryp could promote wound healing, such as epidermal thickening, revascularization, and nerve regeneration. Then the treatment of Tryp was able to promote fibroblast migration and collagen deposition. Moreover, Tryp attenuated inflammation through inducing macrophage polarization to M2 phenotype by suppressing the activation of cGAS-STING pathway.

CONCLUSION

Tryp could reduce the release of inflammatory cytokines, and induce RAW 264.7 polarization to M2 phenotype by targeting cGAS/STING/TBK1 pathways. In summary, Tryp may be a novel medicine for the treatment of PUs in the future.

Identification of β-cycloidal-derived mono-carbonyl curcumin analogs as potential interleukin-6 inhibitor to treat wound healing through QSAR, molecular docking, MD simulation, MM-GBSA calculation

Interleukin-6 (IL-6) is a cytokine that involved in the different phases of wound healing. It is responsible for promoting inflammation, regulating tissue repair scar formation, stimulating the production of extracellular matrix components and recruiting immune cells to the wound site. Therefore, suppressing IL-6 is beneficial for wound healing. However, no small molecules are currently available in the market against the IL-6. As a result, this research gap motivates us to find a potential inhibitor. This study aimed to investigate the wound healing potential of novel β-cycloidal-derived mono-carbonyl curcumin analogs reported in the literature through screening a series of computational studies. The calculated pIC50 value of 18 compounds (below 10) showed that all compounds may have potential therapeutic efficacy. Molecular docking studies revealed that compound C12 (-45.6044 kcal/mol) bound most strongly in the active site of IL-6 compared to the FDA-approved drug clindamycin (-42.3223). The Molecular Dynamic (MD) simulation displayed that lead compound C12 had the highest stability in the active site of IL-6 compared to the reference drug clindamycin. Furthermore, MMGBSA results indicated that C12 (-20.28 kcal/mol) had the highest binding energy compared to clindamycin (-8.36 kcal/mol). The ADMET analysis predicted that C12 are favourable for drug candidates. This study recommended compound C12 as a lead IL-6 inhibitor for future testing and development as therapeutics for wound healing.Communicated by Ramaswamy H. Sarma.

Study on the rationality of small diameter metallic airway stent in treatment of tracheal stenosis in injured rabbits

BACKGROUND

To observe the occurrence of related complications after self-expandable metallic (SEM) airway stents implantation with different diameters at different time points, and to provide theoretical basis for the optimal chioce of existing airway stents in clinical practice.

METHODS

Healthy New Zealand white rabbits were used to establish benign tracheal stenosis models after chest CT examination. Forty-fivemodel rabbits with more than 50% of airway stenosis were divided into two groups. Small-diameter SEM stents (The ratio of stent diameter to airway diameter is nearly 1.0) were implanted in Group A in 21 rabbits, and large-diameter tracheal stents (The ratio of stent diameter to airway diameter is more than 1.2) were implanted in Group B in 24 rabbits. Stent-related complications were observed after stent implantation in 2nd,4th,8th, and 12th week by bronchoscopygross anatomy, pathological and the expressions of IL-1RA, IL-8 and MMP9 in involved tracheal.

RESULTS

The incidence rate of tracheomalacia of stent was significantly higher in group B (24/24 100%) than that in group A (1 /21,4.8%) (P < 0.05). The incidence rate of scar contracture at both ends of stent was significantly higher than in group B (11 / 24,45.8%) that in group A (2 /21, 9.5%) (P < 0.05). The pathological results of both A and B showed that the columnar epithelium of bronchial mucosa began to damage and detach, inflammatory cells infiltrated after 2nd and 4th week of stenting, The epithelium was repaired, the lamina propria glands almost disappeared, collagen fiber proliferation was obvious, and scars were formed after 8th and 12th week of stenting. ELISA results revealed that the expressions of IL-1RA, IL-8, and MMP9 were increased in the stent group than in model rabbit with benign tracheal stenosis. IL-1RA and MMP9 increased at different periods in group B, but the expression of IL-1RA and MMP9 showed a tread of increasing in the early stage and then decreasing in group A.

CONCLUSION

Metal stents can cause different degrees of stent-related complications in rabbits with benign tracheal stenosis. The incidence of stent-induced tracheomalacia and scar contracture were higher in Group B than that in Group A. IL-1RA, IL-8 and MMP9 may be involved in the development of complications after stentimplantation and peak value of group B movered backward. ing.

The naringin/carboxymethyl chitosan/sodium hyaluronate/silk fibroin scaffold facilitates the healing of diabetic wounds by restoring the ROS-related dysfunction of vascularization and macrophage polarization

Chronic diabetic wounds remain a globally recognized clinical challenge, which occurs mainly due to the disturbances of wound microenvironmental induced by high concentrations of reactive oxygen species (ROS). Impairments in angiogenesis and inflammation in the wound microenvironment ultimately impede the normal healing process. Therefore, targeting macrophage and vascular endothelial cell dysfunction is a promising therapeutic strategy. In our study, we fabricated artificial composite scaffolds composed of naringin/carboxymethyl chitosan/sodium hyaluronate/silk fibroin (NG/CMCS/HA/SF) to promote wound healing. The NG/CMCS/HA/SF scaffold demonstrated favorable anti-inflammatory, anti-oxidative, and pro-angiogenic properties in both in vitro and in vivo experiments, effectively promoting the healing of diabetic wounds. The positive therapeutic effects observed indicate that the composite scaffolds have great potential in clinical wound healing applications.

Fibronectin Connecting Cell Sheet Based on Click Chemistry for Wound Repair

As a living repair material, cell sheet exhibits significant potential in wound repair. Nonetheless, wound healing is a complicated and protracted process that necessitates specific repair functions at each stage, including hemostasis and antibacterial activity. In this work, on the basis of harvesting the cell sheet via a photothermal response strategy, a fibronectin attached cell sheet (FACS) is prepared to enhance its wound repair capability. For this purpose, the azide group (N3 ) is initially tagged onto the cell surface through metabolic glycoengineering of unnatural sugars, and then the conjugate (DBCO-fibronectin) comprises of the dibenzocyclooctyne (DBCO) and fibronectin with multiple wound repair functions is linked to N3 using click chemistry. Biological evaluations following this demonstrates that the FACS preparation exhibits excellent biocompatibility, and the fibronectin modification enhances the capacity for cell proliferation and migration. Moreover, in vivo wound healing experiment confirms the reparative efficacy of FACS. It not only has a wound closure rate 1.46 times that of a conventional cell sheet but also reduces inflammatory cell infiltration, promotes hair follicle and blood vessel regeneration, and encourages collagen deposition. This strategy holds enormous clinical potential and paves the way for advanced functional modifications of cell sheets.

Chitosan-based films filled with nanoencapsulated essential oil: Physical-chemical characterization and enhanced wound healing activity

The economic burden of chronic wounds, the complexity of the process of tissue repair and the possibility of resistant bacterial infections, have triggered a significant research interest in the application of natural alternative therapies for wound healing. Biomolecules are intrinsically multi-active, as they affect multiple mechanisms involved in tissue repair phenomenon, including immunomodulatory, anti-inflammatory, cell proliferation, extra cellular matrix remodeling and angiogenesis. Chitosan features a unique combination of attributes, including intrinsic hemostatic, antimicrobial, and immunomodulatory properties, that make it an exceptional candidate for wound management, in the development of wound dressings and scaffolds. In this study, we produced nanoemulsions (NE) loaded with SFO, characterized them, and evaluated their tissue repairing properties. Dynamic light scattering (DLS) analysis confirmed the formation of a nanoemulsion with a droplet size of 21.12 ± 2.31 nm and a polydispersity index (PdI) of 0.159, indicating good stability for up to 90 days. To investigate the potential wound healing effects, SFO-loaded NE were applied on male C57BL/6 mice for seven consecutive days, producing a significantly higher wound closure efficiency (p < 0.05) for the group treated with SFO-loaded NE compared to the control group treated with the saline solution. This finding indicates that the SFO-loaded NE exhibits therapeutic properties that effectively promote wound healing in this experimental model. Then, SFO-loaded NE were incorporated into chitosan:polyvinyl alcohol (PVA)-based films. The inclusion of NE into the polymer matrix resulted in increased lipophilicity reflected by the contact angle results, while decreasing moisture absorption, water solubility, and crystallinity. Moreover, FTIR analysis confirmed the formation of new bonds between SFO-NE and the film matrix, which also impacted on porosity properties. Thermal analysis indicated a decrease in the glass transition temperature of the films due to the presence of SFO-NE, suggesting a plasticizing role of NE, confirmed by XRD results, that showed a decrease in the crystallinity of the blend films upon the addition of SFO-NE. AFM images showed no evidence of NE droplet aggregation in the Chitosan:PVA film matrix. Moisture absorption and water content decreased upon incorporation of SFO-loaded NE. Although the inclusion of NE increased hydrophobicity and water contact angle, the values remained within an acceptable range for wound healing applications. Overall, our results emphasize the significant tissue repairing properties of SFO-loaded NE and the potential of Chitosan:PVA films containing nanoencapsulated SFO as effective formulations for wound healing with notable tissue repairing properties.

Accelerated wound healing after topical application of hyaluronic acid cotton to hemorrhoidectomy wounds in a rat model

Purpose

Anal wounds following hemorrhoidectomy can lead to severe pain and postoperative bleeding, impacting patient recovery and quality of life. Hyaluronic acid (HA) stimulates tissue regeneration and wound healing by accelerating cell migration and proliferation. This study aimed to investigate the differences in wound healing rate and completeness of recovery of perianal wounds topically treated with HA-soaked cotton in a murine model.

Methods

Forty-eight 8-week-old Sprague-Dawley rats with perianal wounds created using a biopsy punch were divided into 2 groups: simple dressing with gauze (control) and topical HA-soaked cotton. A single application of HA-soaked cotton was administered after surgery. Wound healing rate and completeness of recovery were evaluated by measuring the healed area and conducting histological analyses.

Results

The HA-cotton group exhibited a shorter complete wound healing duration compared to the control group (13.9 days vs. 16.4 days, P = 0.031). Differences in wound healing area between the 2 groups were greatest on postoperative day 2 (51.6% vs. 28.8%, P < 0.001). The HA-cotton group exhibited fewer cases of granulation tissue (2 vs. 5) or redness (0 vs. 3) upon complete wound healing. Histologically, the HA-cotton group showed accelerated reepithelialization, rapid shift to lymphocyte-dominant inflammation, enhanced fibroblast proliferation, and increased collagen deposition compared to the control group.

Conclusion

Herein, topical application of HA-soaked cotton on perianal wounds in rats resulted in accelerated wound healing, particularly in the initial stages, and improved completeness of recovery, underscoring the potential of the topical application of HA-soaked cotton on hemorrhoidectomy wounds in human patients to improve wound healing.

The Potential of PIP3 in Enhancing Wound Healing

Given the role of phosphatidylinositol 3,4,5-trisphosphate (PIP3) in modulating cellular processes such as proliferation, survival, and migration, we hypothesized its potential as a novel therapeutic agent for wound closure enhancement. In this study, PIP3 was examined in its free form or as a complex with cationic starch (Q-starch) as a carrier. The intracellular bioactivity and localization of free PIP3 and the Q-starch/PIP3 complexes were examined. Our results present the capability of Q-starch to form complexes with PIP3, facilitate its cellular membrane internalization, and activate intracellular paths leading to enhanced wound healing. Both free PIP3 and Q-starch/PIP3 complexes enhanced monolayer gap closure in scratch assays and induced amplified collagen production within HaCAT and BJ fibroblast cells. Western blot presented enhanced AKT activation by free or complexed PIP3 in BJ fibroblasts in which endogenous PIP3 production was pharmacologically inhibited. Furthermore, both free PIP3 and Q-starch/PIP3 complexes expedited wound closure in mice, after single or daily dermal injections into the wound margins. Free PIP3 and the Q-starch/PIP3 complexes inherently activated the AKT signaling pathway, which is responsible for crucial wound healing processes such as migration; this was also observed in wound assays in mice. PIP3 was identified as a promising molecule for enhancing wound healing, and its ability to circumvent PI3K inhibition suggests possible implications for chronic wound healing.

Natural agents as wound-healing promoters

The management of acute and chronic wounds resulting from diverse injuries poses a significant challenge to clinical practices and healthcare providers. Wound healing is a complex biological process driven by a natural physiological response. This process involves four distinct phases, namely hemostasis, inflammation, proliferation, and remodeling. Despite numerous investigations on wound healing and wound dressing materials, complications still persist, necessitating more efficacious therapies. Wound-healing materials can be categorized into natural and synthetic groups. The current study aims to provide a comprehensive review of highly active natural animal and herbal agents as wound-healing promoters. To this end, we present an overview of in vitro, in vivo, and clinical studies that led to the discovery of potential therapeutic agents for wound healing. We further elucidated the effects of natural materials on various pharmacological pathways of wound healing. The results of previous investigations suggest that natural agents hold great promise as viable and accessible products for the treatment of diverse wound types.

Nano-emodin mediated photodynamic therapy for wound healing of donor site after free gingival graft: A parallel clinical trial

AIM

This study aimed to evaluate the effectiveness of nano-emodin (n-Emo) mediated photodynamic therapy (PDT) as an adjunctive therapy to conventional wound care in patients undergoing free gingival graft (FGG) treatment. The study employed a single-center, parallel, two-blind, randomized, controlled trial design.

METHOD AND MATERIAL

A total of 53 patients requiring FGG treatment were randomly assigned to one of three groups: the n-Emo mediated PDT group, the n-Emo gel group, and the control group. The n-Emo mediated PDT group received n-Emo gel on donor site followed by LED (450 nm, 1000 ± 1400 mW/cm2, 60-80 J/cm2, 60 s), the n-Emo gel group received only n-Emo gel on donor site, and the control group received a placebo gel on donor site. All groups received treatment immediately and 48 h after FGG surgery. Wound healing was assessed based on wound area, bleeding, color match, and epithelialization. Postoperative pain perception was evaluated using a Visual Analogue Scale (VAS), and the number of non-steroidal anti-inflammatory drug (NSAID) intakes was recorded.

RESULTS

The results showed that all groups demonstrated significant improvement in wound healing by day 28, with the n-Emo mediated PDT exhibiting significantly better healing on the 14th, 21st, and 28th day compared to the control group. Additionally, on the 28th day, the n-Emo mediated PDT showed significantly better healing than the n-Emo gel group. The n-Emo mediated PDT also had significantly lower pain scores than the control group. There were no significant differences in the number of NSAID intakes, bleeding, or color match among the groups, but all groups showed improved color match during follow-up. By the third week, all groups had fully epithelialized without significant differences, and no secondary bleeding incidents were reported.

CONCLUSION

The study concludes that n-Emo mediated PDT is an effective adjunctive therapy to conventional wound care for managing complication after surgery at donor site after FGG surgery.

Characterization and comparative evaluation of wound healing potential of Ajugarin I and Ajuga bracteosa Wall. ex Benth

Ajuga bracteosa (family: Lamiaceae), commonly known as kauri booti, is an important ethnomedicinal plant. The current research was conducted to appraise and compare the in vitro antioxidant and antibacterial profiles as well as in vivo wound healing potentials of Ajugarin I and A. bracteosa extract. Ajugarin I and polyphenols in A. bracteosa were enumerated by reversed-phase high-performance liquid chromatography analysis that confirmed significant amounts of Ajugarin I (2.2 ± 0.02 μg/mg DW) and other phenolic compounds (14 out of 17 standards). A. bracteosa (374.4 ± 0.20 µg AAE/mg of DW, 201.9 ± 0.20 µg AAE/mg of DW, 87 ± 0.30%) showed a higher antioxidant profile compared to Ajugarin I (221.8 ± 0.50 µg AAE/mg of DW, 51.8 ± 0.40 µg AAE/mg of DW, 27.65 ± 0.80%) with 1.86-, 3.89-, and 3.15-fold greater activity in ferric reducing antioxidant power, total antioxidant capacity, and free radical scavenging assays, respectively. Likewise, A. bracteosa showed antibacterial activity against 3/5 strains (MIC 25-200 μg/ml) than Ajugarin I (2/5 strains; MIC 50-200 μg/ml). Hemolytic (<2% hemolysis) and dermal toxicity tests rendered both samples non-toxic. Additionally, A. bracteosa (100 ± 2.34% at day 12; 9.33 ± 0.47 days) demonstrated 1.11- and 1.24-fold higher percent wound contraction and epithelization time, respectively, than Ajugarin I (95.6 ± 1.52% at day 12; 11.6 ± 0.47 days) as assessed by an excision wound model in mice. Histopathological examination further reinforced the better wound healing potential of A. bracteosa with good epithelization, collagen synthesis, fibroblast proliferation, and revascularization. Briefly, we endorse the significant comparative antioxidant, antibacterial, and wound healing activities of A. bracteosa and Ajugarin I and present these as prospective candidates for wound healing drugs.

Lespedeza maximowiczii flower absolute promotes skin epithelization, barrier properties, and moisturization-related beneficial responses in human keratinocytes

Lespedeza maximowiczii (LM), a member of the legume family, has tyrosinase inhibitory and estrogenic activities. However, its effects on skin-related biological activities remain unclear. Therefore, the present study aimed to explore the effects of LM flower absolute (LMFAb) on skin-related biological events, especially skin re-epithelization, barrier and moisturizing-related keratinocyte (HaCaT cell) responses. In this study, LMFAb was isolated from LM flowers via solvent extraction and its chemical composition analysis was performed using gas chromatography/mass spectrometry. 5-bromo-2'-deoxyuridine incorporation, Boyden chamber, sprout outgrowth, enzyme-linked immunosorbent, and Western blot assay were used to analyze the biological effects of LMFAb on HaCaT cells (a human epidermal keratinocyte cell line). Twelve components were identified in LMFAb. LMFAb promoted cell proliferation, migration, and sprout outgrowth in HaCaT cells. The absolute enhanced the activations of MAPKs (ERK1/2, JNK, and p38), PI3K and AKT proteins in HaCaT cells and elevated collagen type I and IV levels in HaCaT cell conditioned medium. In addition, LMFAb induced an increase in the expression levels of epidermal barrier proteins (filaggrin and involucrin) in HaCaT cells. Furthermore, LMFAb increased hyaluronan (HA) production and expression of HA synthases (HAS-1, HAS-2, and HAS-3) but decreased HYBID (HA binding protein involved in HA depolymerization) level in HaCaT cells. These findings demonstrate that LMFAb might promote skin re-epithelization, barrier and moisturizing-related beneficial responses in keratinocytes. This study suggests that LMFAb should be considered a potential starting material for the development of cosmetic or pharmaceutical agents that restore the functions of damaged skin.

Metal Nanoparticles: Advanced and Promising Technology in Diabetic Wound Therapy

Diabetic wounds pose a significant challenge to public health, primarily due to insufficient blood vessel supply, bacterial infection, excessive oxidative stress, and impaired antioxidant defenses. The aforementioned condition not only places a significant physical burden on patients' prognosis, but also amplifies the economic strain on the medical system in treating diabetic wounds. Currently, the effectiveness of available treatments for diabetic wounds is limited. However, there is hope in the potential of metal nanoparticles (MNPs) to address these issues. MNPs exhibit excellent anti-inflammatory, antioxidant, antibacterial and pro-angiogenic properties, making them a promising solution for diabetic wounds. In addition, MNPs stimulate the expression of proteins that promote wound healing and serve as drug delivery systems for small-molecule drugs. By combining MNPs with other biomaterials such as hydrogels and chitosan, novel dressings can be developed and revolutionize the treatment of diabetic wounds. The present article provides a comprehensive overview of the research progress on the utilization of MNPs for treating diabetic wounds. Building upon this foundation, we summarize the underlying mechanisms involved in diabetic wound healing and discuss the potential application of MNPs as biomaterials for drug delivery. Furthermore, we provide an extensive analysis and discussion on the clinical implementation of dressings, while also highlighting future prospects for utilizing MNPs in diabetic wound management. In conclusion, MNPs represent a promising strategy for the treatment of diabetic wound healing. Future directions include combining other biological nanomaterials to synthesize new biological dressings or utilizing the other physicochemical properties of MNPs to promote wound healing. Synthetic biomaterials that contain MNPs not only play a role in all stages of diabetic wound healing, but also provide a stable physiological environment for the wound-healing process.

Effects of an Ultra-Polished Scalpel on Incisional Wounds in a Diabetic Model

Inflammation after surgical incisions is related to the degree of tissue damage. Healing with low inflammation is desirable, especially in patients with compromised healing potential. This experimental study was conducted to assess the degree of inflammatory reaction and scar formation from incisions made by an ultra-polished scalpel (UPS). Two paravertebral incisions were made with a conventional scalpel (CS) and a UPS in 18 individual rats with diabetes. The fibrotic tissue (scar) area and expression levels of collagen, transforming growth factor, and matrix metalloproteinases were quantified on postoperative days 3, 7, and 30. The scar widths and areas were significantly lower in the UPS group than in the CS group. The scar widths were 64.3 ± 14.7 µm and 86.8 ± 12.1 µm in the UPS and CS groups, respectively (P = 0.03). The scar areas were 11,398 ± 1595 µm2 in the UPS group and 17,433 ± 3487 µm2 in the CS group (P = 0.014). The UPS group had less inflammation on day 3, less transforming growth factor synthesis on days 3 and 7, lower levels of matrix metalloproteinases, and less collagen synthesis on day 7 than did the CS group. The UPS achieved less local inflammation by reducing the local tissue damage in diabetic rat models, enabling better healing, and resulting in less scar formation. The UPS warrants further clinical study as it may bring beneficial outcomes for patients with impaired healing capability and patients who seek to reduce scarring.

Genome-wide association study identifies genetic variants underlying footrot in Portuguese Merino sheep

BACKGROUND

Ovine footrot caused by Dichelobacter nodosus (D. nodosus) is a contagious disease with serious economic and welfare impacts in sheep production systems worldwide. A better understanding of the host genetic architecture regarding footrot resistance/susceptibility is crucial to develop disease control strategies that efficiently reduce infection and its severity. A genome-wide association study was performed using a customized SNP array (47,779 SNPs in total) to identify genetic variants associated to footrot resistance/susceptibility in two Portuguese native breeds, i.e. Merino Branco and Merino Preto, and a population of crossbred animals. A cohort of 1375 sheep sampled across 17 flocks, located in the Alentejo region (southern Portugal), was included in the analyses.

RESULTS

Phenotypes were scored from 0 (healthy) to 5 (severe footrot) based on visual inspection of feet lesions, following the Modified Egerton System. Using a linear mixed model approach, three SNPs located on chromosome 24 reached genome-wide significance after a Bonferroni correction (p < 0.05). Additionally, six genome-wide suggestive SNPs were identified each on chromosomes 2, 4, 7, 8, 9 and 15. The annotation and KEGG pathway analyses showed that these SNPs are located within regions of candidate genes such as the nonsense mediated mRNA decay associated PI3K related kinase (SMG1) (chromosome 24) and the RALY RNA binding protein like (RALYL) (chromosome 9), both involved in immunity, and the heparan sulfate proteoglycan 2 (HSPG2) (chromosome 2) and the Thrombospodin 1 (THBS1) (chromosome 7) implicated in tissue repair and wound healing processes.

CONCLUSION

This is the first attempt to identify molecular markers associated with footrot in Portuguese Merino sheep. These findings provide relevant information on a likely genetic association underlying footrot resistance/susceptibility and the potential candidate genes affecting this trait. Genetic selection strategies assisted on the information obtained from this study could enhance Merino sheep-breeding programs, in combination with farm management strategies, for a more effective and sustainable long-term solution for footrot control.

Iridoid Glycosides and Coumarin Glycoside Derivatives from the Roots of Nymphoides peltata and Their In Vitro Wound Healing Properties

Nymphoides peltata has been used as a medicinal herb in traditional medicines to treat strangury, polyuria, and swelling. The phytochemical investigation of the MeOH extract of N. peltata roots led to the isolation of three iridoid glycosides and three coumarin glycoside derivatives, which were characterized as menthiafolin (1), threoninosecologanin (2), callicoside C (3), and scopolin (4), as well as two undescribed peltatamarins A (5) and B (6). The chemical structures of the undescribed compounds were determined by analyzing their 1 dimensional (D) and 2D nuclear magnetic resonance (NMR) spectra and using high-resolution (HR)-electrospray ionization mass spectroscopy (ESI-MS), along with the chemical reaction of acid hydrolysis. The wound healing activities of the isolated compounds 1-6 were evaluated using a HaCaT cell scratch test. Among the isolates, scopolin (4) and peltatamarin A (5) promoted HaCaT cell migration over scratch wounds, and compound 5 was the most effective. Furthermore, compound 5 significantly promoted cell migration without adversely affecting cell proliferation, even when treated at a high dose (100 μM). Our results demonstrate that peltatamarin A (5), isolated from N. peltata roots, has the potential for wound healing effects.

Mussel-inspired electroactive, antibacterial and antioxidative composite membranes with incorporation of gold nanoparticles and antibacterial peptides for enhancing skin wound healing

Large skin wounds are one of the most important health problems in the world. Skin wound repair and tissue regeneration are complex processes involving many physiological signals, and effective wound healing remains an enormous clinical challenge. Therefore, there is an urgent need for a strategy to rapidly kill bacteria, promote cell proliferation and accelerate wound healing. At present, electrical stimulation (ES) is often used in the clinical treatment of skin wounds and can simulate the endogenous biological current of the body and accelerate the repair process of skin wounds. However, a single ES strategy has difficulty covering the entire wound area, which may lead to unsatisfactory therapeutic effects. To overcome this deficiency, it is essential to develop a collaborative treatment strategy that combines ES with other treatments. In this study, gold nanoparticles and antibacterial peptides (Os) were loaded on the surface of poly(lactic-co-glycolic acid) (PLGA) material through the reducibility and adhesion of polydopamine (PDA) and improved the electrical activity, anti-inflammatory, antibacterial and biocompatibility properties of the polymer material. At the same time, this composite membrane material (Os/Au-PDA@PLGA) combined with ES was used in wound therapy to improve the wound healing rate. The results show that the new wound repair material has good biocompatibility and can effectively promote cell proliferation and migration. Through the combined application of gold nanoparticles and antibacterial peptides Os, the polymer materials have more efficient bactericidal and antioxidant effects. The antibacterial experiment results showed that gold nanoparticles could further enhance the antibacterial activity of antibacterial peptides. Furthermore, the Os/Au-PDA@PLGA composite membrane has good hydrophilicity and electrical activity, which can provide a more favorable cell microenvironment for wound healing. In vivo studies using a full-thickness skin defect model in rats showed that the Os/Au-PDA@PLGA composite membrane had a better therapeutic effect than the pure PLGA material. More importantly, the combination of the Os/Au-PDA@PLGA composite with ES significantly accelerated the rate of vascularization and collagen deposition and promoted wound healing compared with non-ES controls. Therefore, the combination of the Au/Os-PDA@PLGA composite membrane with ES may provide a new strategy for the effective treatment of skin wounds.

Dynamic optical coherence tomography of chronic venous ulcers

BACKGROUND

Chronic ulcers, especially venous leg ulcers, are a major burden on the healthcare system. To date there are only few non-invasive established procedures for evaluation of blood perfusion in wounds. Dynamic optical coherence tomography (D-OCT) provides images of the skin's superficial vascularisation.

OBJECTIVES

This study aims to investigate if and how the D-OCT measurement of chronic wounds can provide new information about the vascularisation during the healing process.

METHODS

We examined 16 venous ulcers over 16 weeks and evaluated the vessel morphology and density using D-OCT at the wound bed, borders, two centimetres adjacent to the wound und at non-ulcerated skin on the contralateral leg.

RESULTS

In D-OCT scans clumps were unique and the most common vessel type in the wound area of venous ulcers, whereas lines and serpiginous vessels were the most common in non-ulcerated skin. At the wound border mottle and cluster patterns occurred more frequently. Healthy skin showed a significant increase of mesh pattern. Vessel density significantly increased at the wound area compared to non-ulcerated skin. During the healing process the wound border showed the most vascular changes while only an increase in curves was observed in the wound centre. Non-healing wounds had fewer dots and blobs at the borders, fewer dots, coils, clumps, lines and serpiginous vessels at the centre and fewer dots in adjacent skin. Temperature analysis showed higher temperatures in non-ulcerated skin, followed by the wound margin and centre. Non-healing wounds showed the lowest temperatures in the wound centre.

CONCLUSIONS

These results highlight the non-invasive use of D-OCT for the examination and monitoring of wound healing in chronic venous ulcers. D-OCT imaging of blood vessels may offer the potential to detect disorders of wound healing at an early stage, differentiate ulcers of different genesis and to tailor more individualized, patient-oriented therapy.

Topical metformin accelerates wound healing by promoting collagen synthesis and inhibiting apoptosis in a diabetic wound model

The wound healing process, which is a pathophysiological process that includes various phases, is interrupted in diabetes due to hyperglycemia, and since deterioration occurs in these phases, a normal healing process is not observed. The aim of the current study is to investigate the proliferative and antiapoptotic effects of metformin on wound healing after topical application on diabetic and non-diabetic wounds. For this purpose, we applied metformin topically on the full-thickness excisional wound model we created in diabetic and nondiabetic groups. We investigated the effects of metformin on the apoptotic index by the Terminal deoxynucleotidyl transferase mediated dUTP Nick-End Labeling method and on collagen-I, collagen-III, p53, and c-jun expression levels by quantitative reverse transcription polymerase chain reaction technique in wound biopsy tissues. Our results showed that c-jun and p53 mRNA levels and apoptotic index increased with the effect of diabetes, while collagen synthesis was disrupted. As a result of the study, we showed that metformin increases cellular proliferation and has anti-apoptotic effects by increasing collagen-I/III expression and decreasing p53/c-jun level, especially in diabetic wounds and also in normal wounds. In conclusion, the topical effect of metformin on diabetic wounds reversed the adverse effects caused by diabetes, increasing the wound healing rate and improving the wound repair process.

Sucralfate Prevents Pin Site Infections of External Fixators in Open Tibia Fractures

Pin site infections are the main complication of external fixators. The most common pathogens are Staphylococcus epidermidis and Staphylococcus aureus. The incidence of pin site infections ranges from 2% to 30%. Until now, no satisfactory prevention strategy exists. Therefore, we performed this study to assess the effect of a sucralfate gel 25% applied around the pins of external fixation systems in trauma patients with open tibia fractures. We prospectively studied two groups of patients with open tibia fractures treated with external fixators. In group A patients, pin site care was performed with the use of normal saline and plain dressings once a day. In group B patients, pin site care was performed with the use of sucralfate gel 25%. The incidence of pin site infections was 33.33% for patients of group A and 16.67% for patients of group B. Patients of group B showed significantly lower rate of pin site infections compared to patients of group A (p-value = 0.032). No patient experienced any complications related to the local application of the drug. Sucralfate significantly prevents pin site infections of external fixators in open tibia fractures. Therefore, it can be used as a preventive antimicrobial agent for pin site infections in patients with external fixators.

Mechanism and application of β-adrenoceptor blockers in soft tissue wound healing

Soft tissue damage stimulates sympathetic nerves to release large amounts of catecholamine hormones which bind to β-adrenergic receptors (β-ARs) on the cell membrane surface. It activates the downstream effector molecules and impairs soft tissue wound healing. β-blockers specifically inhibit β-ARs activation in acute/chronic skin lesions and ulcerative hemangiomas. They also accelerate soft tissue wound healing by shortening the duration of inflammation, speeding keratinocyte migration and reepithelialization, promoting wound contraction and angiogenesis, and inhibiting bacterial virulence effects. In addition, β-blockers shorten wound healing periods in patients with severe thermal damage by reducing the hypermetabolic response. While β-blockers promote/inhibit corneal epithelial cell regeneration and restores limbal stem/progenitor cells function, it could well accelerate/delay corneal wound healing. Given these meaningful effects, a growing number of studies are focused on examining the efficacy and safety of β-blockers in soft tissue wound repair, including acute and chronic wounds, severe thermal damage, ulcerated infantile hemangioma, corneal wounds, and other soft tissue disorders. However, an intensive investigation on their acting mechanisms is imperatively needed. The purpose of this article is to summerize the roles of β-blockers in soft tissue wound healing and explore their clinical applications.