Wound healing in animals is important to minimize the fitness costs of infection. Logically, a longer healing time is associated with higher risk of infection and higher energy loss. In wild mammals, wounds caused by aggressive intraspecific interactions can potentially have lethal repercussions. Clarifying wounding rate and healing time is therefore important for measuring the severity of the attacks. In addition, impact of secondary damage of wounds (e.g., accidental peeling off of scabs) on heeling time is unknown despite the risk of infection in wild mammals. In baboons, most male injuries have been reported to result from male to male fights. Here, we investigated the relationship between wound size and healing time in wild anubis baboons to clarify the healing cost of physical attacks including secondary damage of wounds. Observations were conducted daily between August 2016 and July 2017 in Kenya for seven adult male anubis baboons. The individual wound rate was one per month on average. In 16 cases, we were able to assess the number of days required for wound healing, and the median healing time was 13 d. Wound healing time was longer for larger wounds. When the scab was peeled off accidentally because of external factors, healing time became longer. One of the causes of scabs' peeling off was baboons' scab-picking behavior, and the behaviour was considered self-injurious behavior. However, its predicted healing cost might not be high. We concluded that wounds less than 800 mm2 (the largest observed in this study) in baboon males have little effect on survival. Our results suggest that lethal wounds by physical attacks rarely occur in male baboons, and that healing time and delay caused by secondary damages can be estimated by measuring wound area.

The purpose of the investigation was to evaluate the effect of the selected bioflavonoids curcumin, resveratrol and baicalin on the wound healing process in an in vitro model. In the study, Balb3t3 and L929 cell lines were used. The first step was the evaluation of the cytotoxicity of the substances tested (MTT assay). Then, using the scratch test (ST), the influence of bioflavonoids on the healing process was evaluated in an in vitro model. The second stage of the work was a mathematical analysis of the results obtained. On the basis of experimental data, the parameters of the Brian and Cousens model were determined in order to determine the maximum value of the cellular and metabolic response that occurs for the examined range of concentrations of selected bioflavonoids. In the MTT assays, no cytotoxic effect of curcumin, resveratrol and baicalin was observed in selected concentrations, while in the ST tests for selected substances, a stimulatory effect was observed on the cell division rate regardless of the cell lines tested. The results obtained encourage further research on the use of substances of natural origin to support the wound healing process.

The two known mammalian gelatinases, 72- and 92-kDa gelatinase, are extracellular matrix metalloproteinases (MMPs) with a potential role in wound healing. The gelatinase activity as a function of wound age was analysed in tissue extracts of partial- and full-thickness wounds in the skin of pigs, using two assay systems. Total gelatinase activity, assessed using a 3H-labelled gelatin assay, was highest in the early healing phases and then decreased as healing proceeded in both wound types. Gelatin zymography, which distinguishes the activities of the two gelatinases, showed that the 92-kDa (MMP-9) gelatinase essentially followed the same pattern as that of total gelatinase activity, whereas the activity of the 72-kDa gelatinase (MMP-2) remained fairly stable, although it was higher than in uninjured skin, over the experimental period, irrespective of wound type. In conclusion, the two gelatinases appear to have different functions in the wound healing process. The 72-kDa gelatinase (MMP-2) is important during the prolonged remodelling phase, whereas the 92-kDa gelatinase (MMP-9) is linked to the epithelialization process and early repair events.

Diabetic foot ulcers are associated with significant morbidity and mortality, and current treatments are far from optimal. Chronic wounds in diabetes are characterised by impaired angiogenesis, leukocyte function, fibroblast proliferation, and keratinocyte migration and proliferation. Methods: We tested the effect of exposure to argon gas on endothelial cell, fibroblast, macrophage and keratinocyte cell cultures in vitro and in vivo of a streptozotocin-induced diabetic mouse model. Results: Exposure to normobaric argon gas promotes multiple steps of the wound healing process. Argon accelerated angiogenesis, associated with upregulation of pro-angiogenic Angiopoietin-1 and vascular endothelial growth factor (VEGF) signalling in vitro and in vivo. Treatment with argon enhanced expression of transforming growth factor (TGF)-β, early recruitment of macrophages and keratinocyte proliferation. Argon had a pro-survival effect, inducing expression of cytoprotective mediators B-cell lymphoma 2 and heme oxygenase 1. Argon was able to accelerate wound closure in a diabetic mouse model. Conclusion: Together these findings indicate that argon gas may be a promising candidate for clinical use in treatment of diabetic ulcers.

A fundamental feature of multicellular organisms is their ability to self-repair wounds through the movement of epithelial cells into the damaged area. This collective cellular movement is commonly attributed to a combination of cell crawling and "purse-string" contraction of a supracellular actomyosin ring. Here we show by direct experimental measurement that these two mechanisms are insufficient to explain force patterns observed during wound closure. At early stages of the process, leading actin protrusions generate traction forces that point away from the wound, showing that wound closure is initially driven by cell crawling. At later stages, we observed unanticipated patterns of traction forces pointing towards the wound. Such patterns have strong force components that are both radial and tangential to the wound. We show that these force components arise from tensions transmitted by a heterogeneous actomyosin ring to the underlying substrate through focal adhesions. The structural and mechanical organization reported here provides cells with a mechanism to close the wound by cooperatively compressing the underlying substrate.

No abstract available

As part of our general objective of investigating indigenous plants used in wound healing in Ghana, we hereby report our findings from some in vitro and in vivo studies related to wound healing activities of Clerodendron splendens G. Don (Verbanaceae). Methanolic extract of the aerial parts of the plant was tested for antimicrobial activity against Gram positive bacteria (Bacillus subtilis, Staphylococcus aureus, Streptococcus faecalis, Micrococcus flavus, as well as resistant strains of Staph. aureus SA1199B, RN4220 and XU212), Gram negative bacteria (Escherichia coli, Pseudomonas aeruginosa, Proteous mirabilis, Klebsiella pneumoniae) and Candida albicans using the micro-well dilution method. Survivor-time studies of the microorganisms, radical scavenging activity using 2,2'-diphenylpicrylhydrazyl (DPPH) and various in vivo wound healing activity studies were also conducted on the extract. The extract exhibited biostatic action against all the test microorganisms with a Minimum Inhibition Concentration (MIC) ranging between 64 and 512 μg/ml and a free radical scavenging property with an IC(50) value of 103.2 μg/ml. The results of the in vivo wound healing tests showed that upon application of C. splendens ointment, there was a reduction in the epithelization period from 26.7 days (control) to 13.6 days along with a marked decrease in the scar area from 54.2 mm(2) (control) to 25.2 mm(2). Significant increase in the tensile strength and hydroxyproline content were also observed as compared to the control and was comparable to nitrofurazone. The above results appear to justify the traditional use of C. splendens in wound healing and treatment of skin infections in Ghana.

High-mobility group box protein-1 (HMGB-1) plays a central role in the inflammatory network, and uncontrolled chronic inflammation can lead to excessive scarring. The aim of this study was to evaluate the anti-inflammatory effects of polydeoxyribonucleotide (PDRN) on scar formation. Sprague-Dawley rats (n = 30) underwent dorsal excision of the skin, followed by skin repair. PDRN (8 mg/kg) was administered via intraperitoneal injection for three (PDRN-3 group, n = 8) or seven (PDRN-7 group, n = 8) days, and HMGB-1 was administered via intradermal injection in addition to PDRN treatment for three days (PDRN-3+HMGB-1 group; n = 6). The scar-reducing effects of PDRN were evaluated in the internal scar area and by inflammatory cell counts using histology and immunohistochemistry. Western blot, immunohistochemistry and immunofluorescence assays were performed to observe changes in type I and type III collagen and the expression of HMGB-1 and CD45. Treatment with PDRN significantly reduced the scar area, inflammatory cell infiltration and the number of CD45-positive cells. In addition, the increased expression of HMGB-1 observed in the sham group was significantly reduced after treatment with PDRN. Rats administered HMGB-1 in addition to PDRN exhibited scar areas with inflammatory cell infiltration similar to the sham group, and the collagen synthesis effects of PDRN were reversed. In summary, PDRN exerts anti-inflammatory and collagen synthesis effects via HMGB-1 suppression, preventing scar formation. Thus, we believe that the anti-inflammatory and collagen synthesis effects of PDRN resulted in faster wound healing and decreased scar formation.

Wound healing due to skin defects is a growing clinical concern. Especially when infection occurs, it not only leads to impair healing of the wound but even leads to the occurrence of death. In this study, a self-healing supramolecular hydrogel with antibacterial abilities was developed for wound healing. The supramolecular hydrogels inherited excellent self-healing and mechanical properties are produced by the polymerization of N-acryloyl glycinamide monomers which carries a lot of amides. In addition, excellent antibacterial properties are obtained by integrating silver nanoparticles (Ag NPs) into the hydrogels. The resultant hydrogel has a demonstrated ability in superior mechanical properties, including stretchability and self-healing. Also, the good biocompatibility and antibacterial ability have been proven in hydrogels. Besides, the prepared hydrogels were employed as wound dressings to treat skin wounds of animals. It was found that the hydrogels could significantly promote wound repair, including relieving inflammation, promoting collagen deposition, and enhancing angiogenesis. Therefore, such self-healing supramolecular hydrogels with composite functional nanomaterials are expected to be used as new wound dressings in the field of healthcare.

Collective cell migration plays important roles in various physiological processes. To investigate this collective cellular movement, various wound-healing assays have been developed. In these assays, a "wound" is created mechanically, chemically, optically, or electrically out of a cellular monolayer. Most of these assays are subject to drawbacks of run-to-run variations in wound size/shape and damages to cells/substrate. Moreover, in all these assays, cells are cultured in open, static (non-circulating) environments. In this study, we reported a microfluidics-based wound-healing assay by using the trypsin flow-focusing technique. Fibroblasts were first cultured inside this chip to a cellular monolayer. Then three parallel fluidic flows (containing normal medium and trypsin solution) were introduced into the channels, and cells exposed to protease trypsin were enzymatically detached from the surface. Wounds of three different widths were generated, and subsequent wound-healing processes were observed. This assay is capable of creating three or more wounds of different widths for investigating the effects of various physical and chemical stimuli on wound-healing speeds. The effects of shear stresses, wound widths, and β-lapachone (a wound healing-promoting chemical) on wound-healing speeds were studied. It was found that the wound-healing speed (total area healed per unit time) increased with increasing shear stress and wound width, but under a shear stress of 0.174 mPa the linear healing speed (percent area healed per unit time) was independent of the wound width. Also, the addition of β-lapachone up to 0.5 μM did not accelerate wound healing. This microfluidics-based assay can definitely help in understanding the mechanisms of the wound-healing process and developing new wound-healing therapies.

Impaired wound healing is a severe clinical challenge and research into finding effective wound healing strategies is underway as there is no ideal treatment. Gelatinous material from the umbilical cord called Wharton's jelly is a valuable source of mesenchymal stem cells which have been shown to aid wound healing. While the cellular component of Wharton's jelly has been the subject of extensive research during the last few years, little is known about the de-cellularized jelly material of the umbilical cord. This is important as they are native niche of stem cells. We have isolated Wharton's jelly from umbilical cords and then fractionated acellular gelatinous Wharton's jelly (AGWJ). Here, we show for the first time that AGWJ enhances wound healing in vitro as well as in vivo for wounds in a murine model. In vivo staining of the wounds revealed a smaller wound length in the AGWJ treated wounds in comparison to control treatment by enhancing cell migration and differentiation. AGWJ significantly enhanced fibroblast cell migration in vitro. Aside from cell migration, AGWJ changed the cell morphology of fibroblasts to a more elongated phenotype, characteristic of myofibroblasts, confirmed by upregulation of alpha smooth muscle actin using immunoblotting. AGWJ treatment of wounds led to accelerated differentiation of cells into myofibroblasts, shortening the proliferation phase of wound healing. This data provides support for a novel wound healing remedy using AGWJ. AGWJ being native biological, cost effective and abundantly available globally, makes it a highly promising treatment option for wound dressing and skin regeneration.

The wound healing process is complex and still poorly understood. Sericin is a silk protein synthesized by silk worms (Bombyx mori). The objective of this study was to evaluate in vivo wound healing effects of a sericin-containing gel formulation in an incision wound model in rats.

Jellyfishes are considered a new potential resource in food, pharmaceutical and biomedical industries. In these latter cases, they are studied as source of active principles but are also exploited to produce marine collagen. In the present work, jellyfish skin polysaccharides (JSP) with glycosaminoglycan (GAG) features were extracted from Rhizostoma pulmo, a main blooming species of Mediterranean Sea, massively augmented by climate leaded "jellyfishication" of the sea. Two main fractions of R. pulmo JSP (RP-JSPs) were isolated and characterized, namely a neutral fraction (RP-JSP1) and a sulphate rich, negatively charged fraction (RP-JSP2). The two fractions have average molecular weights of 121 kDa and 590 kDa, respectively. Their sugar composition was evaluated through LC-MS analysis and the result confirmed the presence of typical GAG saccharides, such as glucose, galactose, glucosamine and galactosamine. Their use as promoters of wound healing was evaluated through in vitro scratch assay on murine fibroblast cell line (BALB/3T3 clone A31) and human keratinocytes (HaCaT). Both RP-JSPs demonstrated an effective confluency rate activity leading to 80% of scratch repair in two days, promoting both cell migration and proliferation. Additionally, RP-JSPs exerted a substantial protection from oxidative stress, resulting in improved viability of treated fibroblasts exposed to H2O2. The isolated GAG-like polysaccharides appear promising as functional component for biomedical skin treatments, as well as for future exploitation as pharmaceutical excipients.

Electrical stimulation (ES) can serve as a therapeutic modality accelerating the healing of wounds, particularly chronic wounds which have impaired healing due to complications from underlying pathology. This review explores how ES affects the cellular mechanisms of wound healing, and its effectiveness in treating acute and chronic wounds. Literature searches with no publication date restrictions were conducted using the Cochrane Library, Medline, Web of Science, Google Scholar and PubMed databases, and 30 full-text articles met the inclusion criteria. In vitro and in vivo experiments investigating the effect of ES on the general mechanisms of healing demonstrated increased epithelialization, fibroblast migration, and vascularity around wounds. Six in vitro studies demonstrated bactericidal effects upon exposure to alternating and pulsed current. Twelve randomized controlled trials (RCTs) investigated the effect of pulsed current on chronic wound healing. All reviewed RCTs demonstrated a larger reduction in wound size and increased healing rate when compared to control groups. In conclusion, ES therapy can contribute to improved chronic wound healing and potentially reduce the financial burden associated with wound management. However, the variations in the wound characteristics, patient demographics, and ES parameters used across studies present opportunities for systematic RCT studies in the future.

To determine the role of thrombomodulin (TM) in corneal epithelial wound healing, and to investigate whether recombinant TM epidermal growth factor-like domain plus serine/threonine-rich domain (rTMD23) has therapeutic potential in corneal epithelial wound healing.

Wounds cause structural and functional discontinuity of an organ. Wound healing, therefore, seeks to re-establish the normal morphology and functionality through intertwined stages of hemostasis, inflammation, proliferation, and tissue remodelling. Ivermectin, a macrolide, has been used as an endectoparasiticide in human and veterinary medicine practice for decades. Here, we show that ivermectin exhibits wounding healing activity by mechanisms independent of its well-known antiparasitic activity. This study aimed to evaluate the wound healing property of ivermectin cream using histochemistry and enzyme-linked immunosorbent assay techniques.

Periodontitis is a set of inflammatory conditions affecting the tissues surrounding the teeth predominantly sustained by bacterial infections. The aim of the work was the design and the development of scaffolds based on biopolymers to be inserted in the periodontal pocket to restore tissue integrity and to treat bacterial infections. Nanofibrous scaffolds were prepared by means of electrospinning. Gelatin was considered as base component and was associated to low and high molecular weight chitosans and alginate. The scaffolds were characterized by chemico-physical properties (morphology, solid state-FTIR and differential scanning calorimetry (DSC)-surface zeta potential and contact angle), and mechanical properties. Moreover, preclinical properties (cytocompatibility, fibroblast and osteoblast adhesion and proliferation and antimicrobial properties) were assessed. All the scaffolds were based on cylindrical and smooth nanofibers and preserved their nanofibrous structure upon hydration independently of their composition. They possessed a high degree of hydrophilicity and negative zeta potentials in a physiological environment, suitable surface properties to enhance cell adhesion and proliferation and to inhibit bacteria attachment. The scaffold based on gelatin and low molecular weight chitosan proved to be effective in vitro to support both fibroblasts and osteoblasts adhesion and proliferation and to impair the proliferation of Streptococcus mutans and Aggregatibacter actinomycetemcomitans, both pathogens involved in periodontitis.

In contact with the external environment, the cornea can easily be injured. Although corneal wounds generally heal rapidly, the pain and increased risk of infection associated with a damaged cornea, as well as the impaired healing observed in some individuals, emphasize the need for novel treatments to accelerate corneal healing. We previously demonstrated in epidermal keratinocytes that the glycerol channel aquaporin-3 (AQP3) interacts with phospholipase D2 (PLD2) to produce the signaling phospholipid phosphatidylglycerol (PG), which has been shown to accelerate skin wound healing in vivo. We hypothesized that the same signaling pathway might be operational in corneal epithelial cells.

In this study, the antioxidant properties of Arum maculatum plant were evaluated. This study reported for the first time the wound healing activity of the methanol extract of A. maculatum fruits. This study aimed to assess and determine the possible pharmacological activities of A. maculatum and evaluate its potential to act as a wound care plant.

No abstract available