Impact of wound duration on diabetic foot ulcer healing: evaluation of a new sucrose octasulfate wound dressing

OBJECTIVE

A common and frequent complication of diabetes is diabetic foot ulcers (DFU), which can have high treatment costs and severe adverse events. This study aims to evaluate the effects of wound duration on wound healing and the impact on costs, including treatment with a new sucrose octasulfate dressing compared with a control dressing.

METHOD

Based on the Explorer study (a two-armed randomised double-blind clinical trial), a cost-effectiveness analysis compared four different patient groups distinguished by their wound duration and additionally two DFU treatment options: a sucrose octasulfate dressing and a neutral dressing (as control). Clinical outcomes and total direct costs of wound dressings were evaluated over 20 weeks from the perspective of the Social Health Insurance in Germany. Simulation of long-term outcomes and costs were demonstrated by a five cycle Markov model.

RESULTS

The results show total wound healing rates between 71% and 14.8%, and direct treatment costs for DFU in the range of €2482-3278 (sucrose octasulfate dressing) and €2768-3194 (control dressing). Patients with a wound duration of ≤2 months revealed the highest wound healing rates for both the sucrose octasulfate dressing and control dressing (71% and 41%, respectively) and had the lowest direct treatment costs of €2482 and €2768, respectively. The 100-week Markov model amplified the results. Patients with ≤2 months' wound duration achieved wound healing rates of 98% and 88%, respectively and costs of €3450 and €6054, respectively (CE=€3520, €6864). Sensitivity analysis revealed that the dressing changes per week were the most significant uncertainty factor.

CONCLUSION

Based on the findings of this study, early treatment of DFU with a sucrose octasulfate dressing is recommended from a health economic view due to lower treatment costs, greater cost-effectiveness and higher wound healing rates.

[Sucrose octasulfate-evidence in the treatment of chronic wounds]

Patients with chronic wounds should receive wound treatment in addition to causative therapy. In this context, the lack of adequate evidence for wound healing products has been repeatedly discussed. Using the example of TLC-sucrose octasulfate (TLC: technology lipido-colloid), the present review shows that there is significant data with good evidence and comparability in this area. One therapeutic approach to promote wound healing is the inhibition of matrix-metalloproteinases, for example by sucrose octasulfate. For wound products containing TLC-sucrose octasulfate, several sequential clinical studies have been conducted in recent years. The WHAT study was an open randomized controlled trial (RCT) with 117 patients with venous leg ulcers (VLU). The CHALLENGE study was a double-blind RCT with 187 patients with VLU. The SPID study was a pilot study with 33 patients with diabetic foot ulcers (DFU). The two prospective, multicenter clinical pilot studies NEREIDES and CASSIOPEE examined a total of 88 patients with VLU in different phases of healing. In the REALITY study, a pooled data analysis was performed on eight observational studies with 10,220 patients with chronic wounds of different genesis. In the double-blind, two-armed EXPLORER RCT, 240 patients with neuro-ischemic DFU were followed from first presentation until complete healing. In all studies, a significant promotion of wound healing could be shown by the use of wound healing products with TLC-sucrose octasulfate.

Enzyme therapy: a forerunner in catalyzing a healthy society?

INTRODUCTION

The use of enzymes in various industries has been prevalent for centuries. However, their potency as therapeutics remained latent until the late 1950 s, when scientists finally realized the gold mine they were sitting on. Enzyme therapy has seen rapid development over the past few decades and has been widely used for the therapy of myriad diseases, including lysosomal storage disorders, cancer, Alzheimer's disease, irritable bowel syndrome, exocrine pancreatic insufficiency, and hyperuricemia. Enzymes are also used for wound healing, the treatment of microbial infections, and gene therapy.

AREAS COVERED

This is a comprehensive review of the therapeutic use of enzymes that can act as a guidepost for researchers and academicians and presents a general overview of the developments in enzyme therapy over the years, along with updates on recent advancements in enzyme therapy research.

EXPERT OPINION

Although enzyme therapy is immensely beneficial and induces little auxiliary damage, it has several drawbacks, ranging from high cost, low stability, low production, and hyperimmune responses to the failure to cure a variety of the problems associated with a disease. Further fine-tuning and additional clinical efficacy studies are required to establish enzyme therapy as a forerunner to catalyzing a healthy society.

Effect of gallium maltolate on a model of chronic, infected equine distal limb wounds

Distal limb wounds are common injuries sustained by horses and their healing is fraught with complications due to equine anatomy, prevalence of infection, and challenges associated with wound management. Gallium is a semi-metallic element that has been shown to possess antimicrobial properties and aid in wound healing in various preclinical models. The effects of Gallium have not been studied in equine wound healing. Therefore, the objective of this study was to compare healing rates between gallium-treated and untreated wounds of equine distal limbs and to demonstrate the antimicrobial effects of gallium on wounds inoculated with S. aureus. Using an established model of equine wound healing we demonstrated beneficial effects of 0.5% topical gallium maltolate on equine wound healing. Specifically we documented reduced healing times, reduced bioburden, and reduced formation of exuberant granulation tissue in wounds treated with gallium maltolate as compared with untreated wounds. Gallium appeared to exert its beneficial effects via its well-described antimicrobial actions as well as by altering the expression of specific genes known to be involved in wound healing of horses and other animals. Specifically, gallium maltolate appeared to increase expression of transforming growth factor-β in both infected and un-infected wounds. Further work is needed to document the effects of gallium on naturally occurring equine wounds and to compare the effects of gallium with other wound treatment options. These data, however, suggest that gallium may be an attractive and novel means of improving equine distal limb wound healing.

Clinical evaluation of polyabsorbent TLC-NOSF dressings on chronic wounds: a prospective, observational, multicentre study of 1140 patients

Objective:

The superior wound healing properties and cost-effectiveness of TLC-NOSF dressings in the local treatment of chronic wounds have already been demonstrated by several randomised controlled trials (RCTs) at a high quality level. Therefore, this study aimed to evaluate the efficacy and safety of new TLC-NOSF dressings with polyabsorbent fibres in an unselected population of patients under real-life conditions.

Method:

A large, prospective, multicentre, observational study with two polyabsorbent TLC-NOSF dressings (UrgoStart Plus Pad and UrgoStart Plus Border, Laboratoires Urgo, France) was conducted in Germany between July 2017 and December 2018. Main outcomes included wound healing rate, clinical assessment of wound healing progression, local tolerability and acceptance of dressings.

Results:

A total of 1140 patients with chronic wounds of various aetiologies (leg ulcers, diabetic foot ulcers, pressure ulcers, etc.) were treated with the investigated dressings in 130 centres, for a mean duration of 56±34 days. By the final visit, 48.5% of wounds had healed and 44.8% had improved. Similar results were reported regardless of wound aetiology or regardless of proportions of sloughy and granulation tissue at the start of treatment. According to the subgroup analysis by wound duration, the sooner the TLC-NOSF treatment was initiated, the better the clinical outcomes for all types of wounds. The dressings were very well tolerated and accepted by the patients.

Conclusion:

These results are consistent with those from RCTs conducted on TLC-NOSF dressings. They complete the evidence on the good healing properties and safety profile of these dressings, especially in non-selected patients treated in current practice, and regardless of the characteristics of wounds and patients. They support the use of the dressings as a first-line intervention and until wound healing in the management of chronic wounds, in association with appropriate standard of care.

The efficacy of a traditional medicine preparation on second-degree burn wounds in rats

ETHNOPHARMACOLOGICAL RELEVANCE

Lime Salve (L.S) has been well documented from the 9th to the 19th century AD by traditional Iranian medicine (TIM) as an effective remedy for burn healing.

AIM OF THE STUDY

The present study was undertaken to evaluate the healing effect and related underlying mechanisms of Lime Salve in a model of deep second-degree thermal burn in male Wistar rats.

MATERIALS AND METHOD

L.S was made up of a combination of refined calcium hydroxide powder, beeswax and sesame oil and its quality control was assessed. A deep second-degree burn was created by a hot plate in 48 male Wistar rats. Afterwards, they were randomly divided into four groups including normal saline (C group), L.S (T group), basement of formulation composed of beeswax and sesame oil (B group) and silver sulfadiazine (S group). On days 5, 10, 17 and 24, the wounds were digitally photographed by a camera and after sacrifice of the rats, skin samples were obtained for performing qRT-PCR, immunohistochemistry staining and histological examination.

RESULTS

L.S prominently augmented the wound closure rate, neovascularization on day 10 and collagen formation on days 17 and 24 in comparison with the C group. Furthermore, the Salve-exposed specimens showed a significant higher epithelialization during the experiment with a peak on day 24. qRT-PCR also showed that on day 10, VEGF and TGF-β1 genes were significantly higher in the T group as compared with the C group. Also, MMP-9 and MMP-2 genes had a significant peak of expression on day 17 and rapid reduction of expression on day 24. Expression levels of IL-6 and TNF-α genes peaked on day 10 in the T group, followed by a progressive reduction until the end of the examination.

CONCLUSION

L.S could effectively accelerate the healing process of deep second-degree burn wounds and therefore, it may be recommended as a promising topical medication for treating burn wounds in the future clinical trials.

Effectiveness of autologous platelet-rich plasma gel in the treatment of hard-to-heal leg ulcers: a randomised control trial

OBJECTIVE

Regenerative medicine products such as autologous platelet-rich plasma (autologous PRP) gel may speed up the process of healing. Clinical studies show promising results in the treatment of diabetic foot ulcers (DFUs), however there is lack of scientific evidence of autologous PRP effectiveness in treating leg ulcers of other aetiology. This study evaluates the effectiveness of autologous PRP gel in the treatment of hard-to-heal leg ulcers compared with existing conventional treatment.

METHOD

A prospective, randomised controlled, open-labelled clinical trial was carried out between 2014 and 2018. An eight-week study protocol was chosen or until 100% wound re-epithelialisation was observed. Wound size reduction, granulation tissue formation, microbiological wound bed changes and safety were evaluated.

RESULTS

A total of 69 patients (35 in the autologous PRP group and 34 in the control group) were included in the study; 25.71% of the autologous PRP group and 17.64% of control group had ulcers completely re-epithelialised (p>0.05). Wound size reduction in the autologous PRP group was 52.35% and 33.36% in the control group (p=0.003). The autologous PRP group showed superiority over conventional treatment in wound bed coverage with granulation (p=0.001). However, more frequent wound contamination was observed at the end of treatment in the autologous PRP group (p=0.024). No severe adverse events were noted during the study. Both treatment methods were considered equally safe.

CONCLUSION

Topical application of autologous PRP gel in leg ulcers of various aetiology show beneficial results in wound size reduction and induces the granulation tissue formation. However, it is associated with more frequent microbiological wound contamination.

New Evidence and Insights on Dalbavancin and Wound Healing in a Mouse Model of Skin Infection

Dalbavancin is an effective antibiotic that is widely used to treat skin infection. Our aim was to determine the effect of dalbavancin administration on wound healing compared to that of vancomycin and to elucidate if epidermal growth factor receptor (EGFR), matrix metalloproteinase 1 (MMP-1), MMP-9, and vascular endothelial growth factor (VEGF) could be involved in its therapeutic mechanism. A mouse model of methicillin-resistant Staphylococcus aureus (MRSA) skin infection was established. Mice were treated daily with vancomycin (10 mg/kg) and weekly with dalbavancin at day 1 (20 mg/kg) and day 8 (10 mg/kg). After 14 days, wounds were excised, and bacterial counts were performed. Wound healing was assessed by histological and immunohistochemical staining, followed by protein extraction and immunoblotting. Our microbiological results confirmed that both dalbavancin and vancomycin are effective in reducing the bacterial load in wounds. The dalbavancin group showed a strong effect compared with infected untreated animals and the vancomycin-treated group. The wounds treated with dalbavancin showed robust epidermal coverage with reconstitution of the regular and keratinized epidermal lining and well-organized granulation tissue with numerous blood vessels, although slightly less than that in the uninfected group. While in the vancomycin-treated group the epithelium appeared, in general, still hypertrophic, the granulation tissue appeared even less organized. We observed elevated EGFR and VEGF expression in both treated groups, although it was higher in dalbavancin-treated mice. MMP-1 and MMP-9 were decreased in uninfected tissue and in both treated tissues compared with untreated infected wounds. This study showed faster healing with dalbavancin treatment that might be associated with higher EGFR and VEGF levels.

Evaluation of Cypholophus macrocephalus sap as a treatment for infected cutaneous ulcers in Papua New Guinea

Cypholophus macrocephalus sap is used to treat bacterially infected cutaneous leg ulcers in Papua New Guinea. High resolution LC-MS analysis of the sap revealed it to be rich in sulphated flavonoids. We assessed the effects of the sap on the differentiation and pro-inflammatory anti-microbial responses of M1 macrophages using IL-6 and TNF-α ELISAs and found significant increases in M1 macrophage IL-6 expression with concentrations as low as 243 ng/ml sap. Neutrophil IL-6 and TNF-α expression was also significantly increased but to a lesser degree. Matrix metalloproteinases (MMPs) 1, 2, 8 and 9 which are known to contribute to the toxic nature of wound exudates were inhibited by the sap at 24 μg/ml. The sap was tested with several bacterial species known to colonize cutaneous ulcers in Papua New Guinea but proved not to be active. Cypholophus sap stimulates pro-inflammatory, anti-microbial M1 macrophage and neutrophil responses at very low concentrations, whilst also inhibiting MMPs. The combination of an enhanced innate immune response and inhibition of MMPs in ulcer exudate, may contribute to the eradication of bacteria and healing of these infected ulcers. The sap concentrations used in these assays are readily achievable in an in vivo context.

Microbiome-skin-brain axis: A novel paradigm for cutaneous wounds

Chronic wounds cause a significant burden on society financially, medically, and psychologically. Unfortunately, patients with nonhealing wounds often suffer from comorbidities that further compound their disability. Given the high rate of depressive symptoms experienced by patients with chronic wounds, further studies are needed to investigate the potentially linked pathophysiological changes in wounds and depression in order to improve patient care. The English literature on wound healing, inflammatory and microbial changes in chronic wounds and depression, and antiinflammatory and probiotic therapy was reviewed on PubMed. Chronic wound conditions and depression were demonstrated to share common pathologic features of dysregulated inflammation and altered microbiome, indicating a possible relationship. Furthermore, alternative treatment strategies such as immune-targeted and probiotic therapy showed promising potential by addressing both pathophysiological pathways. However, many existing studies are limited to a small study population, a cross-sectional design that does not establish temporality, or a wide range of confounding variables in the context of a highly complex and multifactorial disease process. Therefore, additional preclinical studies in suitable wound models, as well as larger clinical cohort studies and trials are necessary to elucidate the relationship between wound microbiome, healing, and depression, and ultimately guide the most effective therapeutic and management plan for chronic wound patients.

Evaluation of a superabsorbent wound dressing, patient and clinician perspective: a case series

Objective:

The primary objective of this study was to evaluate the fluid management capabilities of a superabsorbent wound dressing (Zetuvit Plus Silicone), with secondary objectives related to parameters that support whether the dressing enables undisturbed healing.

Method:

This study was an open labelled non-comparative study. Patients included in the study were selected by the clinical investigator(s) according to whether the patient required a dressing for the management of moderately to highly exuding wounds.

Results:

A total of 50 patients were included in the study. Results related to the primary objective demonstrated that the superabsorbent wound dressing was able to absorb all levels of exudate across the range (low to high). At each assessment time point these results show that in 98% of assessments the superabsorbent dressing was rated as ‘very good’ (91%) or ‘good’ (7%) at exudate management. Secondary objectives relating to wound bed preparation, healing and management of pain were also positive. Additionally, at the end of each patient treatment, the dressing's fluid management capabilities were rated overall as ‘excellent’ (100% of cases). There was little pain associated with the wound or at dressing change throughout the study and its flexibility/conformability allowed for comfort and patient satisfaction aligned with increased quality of life. Additionally, inclusion of a silicone adhesive layer allowed painless and atraumatic removal of the dressing, increasing patient comfort, both during wear and at dressing removal, and supported the description of enabling undisturbed wound healing.

Conclusion:

The superabsorbent wound dressing achieved the primary objective relating to wound exudate management in all the assessments undertaken in this study. In addition, the silicone interface allowed for undisturbed healing as evidenced by little or no adherence of the dressing to underlying tissue, preventing damage to periwound skin. Overall, the superabsorbent wound dressing with the addition of the silicone interface could offer advantages over other superabsorbent polymer dressings (that might adhere to the wound surface) or silicone wound dressings (that might not have the absorbent properties of this type of dressing).

Effect of Hydrogel Enriched With Alginate, Fatty Acids, and Vitamins A and E on Pressure Injuries: A Case Series

Pressure injuries are a common kind of skin lesion that may be difficult to treat. The objective of this study was to analyze the effect of hydrogel enriched with alginate, fatty acids, and vitamins A and E in the treatment of pressure injuries. This case series with 12-week follow-up included applying daily dressings with hydrogel, maintaining a photographic record, using planimetry to calculate the lesion area, and classifying the healing process using the Pressure Ulcer Scale for Healing (PUSH). In addition, exudate collection from the ulcers was performed in the beginning and after 12 weeks of treatment to determine the dosage of metalloproteinase 9 (MMP9) and tissue inhibitor of metalloproteinase 1 (TIMP1). Of the 13 patients included in the study, 2 died and 11 were monitored for 12 weeks. Only 1 patient showed full wound healing, but all patients showed a significant 12.19% (p = .023) reduction in the lesion area. The PUSH score was also significantly reduced from 15.9 to 10.54 (p = .0052). Relative to the dosage of metalloproteinase and its inhibitor, there was a reduction in the level of MMP9 and there was no change in the level of TIMP1. This study showed that hydrogel enriched with alginate, fatty acids, and vitamins A and E provided promising results for the treatment of pressure injuries by reducing the lesion area, the general PUSH score, and the amount of MMP9 in the wounds' microenvironment.

Development of microRNA-21 mimic nanocarriers for the treatment of cutaneous wounds

Rationale: Of the regulatory microRNAs expressed in the wounded skin, microRNA-21 (miR21) plays a pivotal role in wound repair by stimulating re-epithelialization, an essential feature to facilitate healing and reduce scar formation. Despite their crucial roles in wound healing, synthetic exogenous microRNAs have limited applications owing to the lack of an appropriate delivery system. Herein, we designed an miR21 mimic nanocarrier system using facial amphipathic bile acid-conjugated polyethyleneimines (BA-PEI) for the intracellular and transdermal delivery of synthetic miR21 molecules to accelerate wound repair. Methods: To design miR21 mimic nanocarriers, BA-conjugated PEIs prepared from three different types of BA at molar feed ratios of 1 and 3 were synthesized. The intracellular uptake efficiency of synthetic miR21 mimics was studied using confocal laser scanning microscopy and flow cytometry analysis. The optimized miR21/BA nanocarrier system was used to evaluate the wound healing effects induced by miR21 mimics in human HaCaT keratinocytes in vitro and a murine excisional acute wound model in vivo. Results: The cell uptake efficiency of miR21 complexed with BA-conjugated PEI was dramatically higher than that of miR21 complexed with PEI alone. Deoxycholic acid (DA)-modified PEI at a molar feed ratio of 3:1 (DA3-PEI) showed the highest transfection efficiency for miR21 without any increase in toxicity. After effective transdermal and intracellular delivery of miR21/DA3 nanocarriers, miR21 mimics promoted cell migration and proliferation through the post-transcriptional regulation of programmed cell death protein 4 (PDCD4) and matrix metalloproteinases. Thus, miR21 mimic nanocarriers improved both the rate and quality of wound healing, as evident from enhanced collagen synthesis and accelerated wound re-epithelialization. Conclusion: Our miRNA nanocarrier systems developed using DA3-PEI conjugates may be potentially useful for the delivery of synthetic exogenous miRNAs in various fields.

Chronic Hypoxia-Induced Microvessel Proliferation and Basal Membrane Degradation in the Bone Marrow of Rats Regulated through the IL-6/JAK2/STAT3/MMP-9 Pathway

Chronic hypoxia (CH) is characterized by long-term hypoxia that is associated with microvessel proliferation and basal membrane (BM) degradation in tissues. The IL-6/JAK2/STAT3/MMP-9 pathway has been described in a variety of human cancers and plays an essential role in microvessel proliferation and BM degradation. Therefore, this study investigated the role of the IL-6/JAK2/STAT3/MMP-9 pathway in hypoxia-mediated microvessel proliferation and BM degradation in the rat bone marrow. Eighty pathogen-free Sprague Dawley male rats were randomly divided into four groups (20 per group)—control group, CH group (exposed to hypoxia in a hypobaric chamber at a simulated altitude of 5000 m for 28 d), CH + STAT3 inhibitor group (7.5 mg/kg/d), and CH + DMSO group. Microvessel density (MVD) and BM degradation in the bone marrow were determined by immunofluorescence staining and transmission electron microscopy. Serum IL-6 levels were assessed by enzyme-linked immunosorbent assay (ELISA), and the levels of P-JAK2, P-STAT3, and MMP-9 were assessed by western blot analysis and real-time reverse transcription PCR (RT-PCR). Hypoxia increased serum IL-6 levels, which in turn increased JAK2 and STAT3 phosphorylation, which subsequently upregulated MMP-9. Overexpression of MMP-9 significantly promoted the elevation of MVD and BM degradation. Inhibition of STAT3 using an inhibitor, SH-4-54, significantly downregulated MMP-9 expression and decreased MVD and BM degradation. Surprisingly, STAT3 inhibition also decreased serum IL-6 levels and JAK2 phosphorylation. Our results suggest that the IL-6/JAK2/STAT3/MMP-9 pathway might be related to CH-induced microvessel proliferation and BM degradation in the bone marrow.

Human Skin Keratinocytes on Sustained TGF-β Stimulation Reveal Partial EMT Features and Weaken Growth Arrest Responses

Defects in wound closure can be related to the failure of keratinocytes to re-epithelize. Potential mechanisms driving this impairment comprise unbalanced cytokine signaling, including Transforming Growth Factor-β (TFG-β). Although the etiologies of chronic wound development are known, the relevant molecular events are poorly understood. This lack of insight is a consequence of ethical issues, which limit the available evidence to humans. In this work, we have used an in vitro model validated for the study of epidermal physiology and function, the HaCaT cells to provide a description of the impact of sustained exposure to TGF-β. Long term TGF-β1 treatment led to evident changes, HaCaT cells became spindle-shaped and increased in size. This phenotype change involved conformational re-arrangements for actin filaments and E-Cadherin cell-adhesion structures. Surprisingly, the signs of consolidated epithelial-to-mesenchymal transition were absent. At the molecular level, modified gene expression and altered protein contents were found. Non-canonical TGF-β pathway elements did not show relevant changes. However, R-Smads experienced alterations best characterized by decreased Smad3 levels. Functionally, HaCaT cells exposed to TGF-β1 for long periods showed cell-cycle arrest. Yet, the strength of this restraint weakens the longer the treatment, as revealed when challenged by pro-mitogenic factors. The proposed setting might offer a useful framework for future research on the mechanisms driving wound chronification.

Pholiota nameko Polysaccharides Promotes Cell Proliferation and Migration and Reduces ROS Content in H2O2-Induced L929 Cells

Pholiota nameko, a type of edible and medicinal fungus, is currently grown extensively for food and traditional medicine in China and Japan. It possesses various biological activities, such as anti-inflammatory, anti-hyperlipidemia and antitumor activities. However, P. nameko has rarely been discussed in the field of dermatology; identifying its biological activities could be beneficial in development of a new natural ingredient used in wound care. To evaluate its in vitro wound healing activities, the present study assessed the antioxidant and anti-collagenase activities of P. nameko polysaccharides (PNPs) prepared through fractional precipitation (40%, 60% and 80% (v/v)); the assessments were conducted using reducing power, hydroxyl radical scavenging activity, dichloro-dihydro-fluorescein diacetate and collagenase activity assays. The ability of PNPs to facilitate L929 fibroblast cell proliferation and migration was assessed using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and scratch assays. The findings indicated that, among all fractions, PNP-80 showed the best antioxidant and anti-collagenase activity, as measured by their reducing power (IC₅₀ of PNP-80 was 2.43 ± 0.17 mg/mL), the hydroxyl radical scavenging (IC₅₀ of PNP-80 was 2.74 ± 0.11 mg/mL) and collagenase activity assay, and significantly reduced cellular ROS content, compared with that of H₂O₂-induced L929 cells. Moreover, PNP-80 significantly promoted L929 fibroblast proliferation and migration, compared with the control group. Overall, we suggested that PNP-80 could be a promising candidate for further evaluation of its potential application on wound healing.

Cost-effectiveness of TLC-sucrose octasulfate versus control dressings in the treatment of diabetic foot ulcers

Objective:

Diabetes is one of the most widespread diseases in Germany. Common complications are diabetic foot ulcers (DFU), which are associated with a cost-intensive treatment and serious adverse events, such as infections, amputations. This cost-effectiveness analysis compares two treatment options for patients with DFU: a TLC-NOSF dressing versus a neutral dressing, assessed through a European double-blind randomised controlled trial (RCT), Explorer.

Methods:

The evaluation of the clinical outcomes was associated to direct costs (costs for dressings, nursing time, hospitalisation etc.) of both dressings, from the perspective of the statutory health insurance in Germany. Due to the long mean healing time of a DFU, the observation period was extended from 20 to 100 weeks in a Markov model.

Results:

After 20 weeks, and with complete closure as a primary endpoint, the model revealed direct treatment costs for DFU of €2,864.21 when treated with a TLC-NOSF dressing compared with €2,958.69 with the neutral control dressing (cost-effectiveness: €6,017.25 versus €9,928.49). In the Markov model (100 weeks) the costs for the TLC-NOSF dressing were €5,882.87 compared with €8,449.39 with the neutral dressing (cost-effectiveness: €6,277.58 versus €10,375.56). The robustness of results was underlined by several sensitivity analyses for varying assumptions. The frequency of weekly dressing changes had the most significant influence in terms of parameter uncertainty.

Conclusion:

Overall, the treatment of DFU with a TLC-NOSF dressing is supported from a health economic perspective, because both the treatment costs and the cost-effectiveness were superior compared with the neutral wound dressing.

Uncontrolled gelatin degradation in non-healing chronic wounds

OBJECTIVE

To compare matrix metalloproteinase (MMP)-9 and the antiproteinase tissue inhibitor of metalloproteinases (TIMP)-1 in wound fluids and sera from patients with chronic non-healing or acute healing wounds. In addition, the functional consequences on MMP-9 activity and general gelatinase activity were assessed.

METHOD

In this observational study, samples were collected from patients with venous leg ulcers (VLUs), patients with type 2 diabetes with neuropathic foot ulcers (DFUs), and from another cohort of VLU patients with sterile split-thickness skin graft donor sites after autologous skin grafting, serving as healing control wounds. MMP-9 and TIMP-1 concentrations were determined by enzyme-linked immunosorbent assays. MMP-9 and gelatinase activities were determined in wound fluids in subsets of the patients.

RESULTS

A total of 24 patients took part in the study. No significant differences in MMP-9 wound fluid levels were found among the three groups. TIMP-1 levels were markedly and significantly lower in the two chronic wound groups resulting in a severely unbalanced MMP-9/TIMP-1 ratio, especially notable in the VLU group and possibly in the elevated endogenous MMP-9 activity (p<0.01) compared with the acute wound fluids. At least 20% of the chronic wound fluids displayed atypical patterns on gelatin zymography and showed high general gelatinase activity that was not inhibited by either TIMP-1 or by a gelatinase inhibitor (AG3340). MMP-9 levels were higher in the sera of the patients with type 2 diabetes.

CONCLUSION

We hypothesise that non-MMP proteinases contribute to matrix destruction in a significant number of chronic wounds. Blocking the excessive MMP-9 activity may be insufficient to normalise wound healing. The reasons and effects of the very low TIMP-1 levels in chronic wounds need further clarification.

Interim Results of the Remede d'Or Study: A Multicenter, Single-Blind, Randomized, Controlled Trial to Assess the Safety and Efficacy of an Innovative Topical Formulation of Erythropoietin for Treating Diabetic Foot Ulcers

Objective: To inform on the interim results of the Remede d'Or study, which is a prospective, multicenter, single-blind, randomized, controlled clinical study on the safety and efficacy of RMD-G1, a topical carbopol-based hydrogel with a fibronectin matrix whose active pharmaceutical ingredient is erythropoietin (EPO), for treating diabetic foot ulcers (DFU). Approach: The trial will comprise 20 patients with type 2 diabetes mellitus with neuroischemic DFUs who will be randomized into two groups: (1) a control group in which standard-of-care (SOC) will be used to treat the DFUs, and (2) a test group in which SOC and RMD-G1 will be used to treat the DFUs. On day 0, all participants will be randomized to receive either RMD-G1 and SOC treatment or SOC alone. The primary endpoint of the study is complete closure of the DFU within the 12-week study period following daily treatments and dressing changes. Results: Interim results reveal that those DFUs which were treated with RMD-G1 responded positively: there was a significant reduction in the wound areas. In contrast, the condition of those DFUs which were treated with only SOC deteriorated. Innovation: To date, no topical therapies with proven efficacy for treating DFUs exist. Topical application of EPO-based RMD-G1 in conjunction with SOC to a DFU accelerates their healing and closure. Conclusions: The interim results of this trial indicate that topical RMD-G1 is a safe adjunctive therapy to SOC, which accelerates the closure of a DFU. RMD-G1 is safe pharmaceutical because EPO has a proven safety profile.

Matrix metalloproteases and TIMPs as prognostic biomarkers in breast cancer patients treated with radiotherapy: A pilot study

Breast cancer (BC) is the most common tumour in women and one of the most important causes of cancer death worldwide. Radiation therapy (RT) is widely used for BC treatment. Some proteins have been identified as prognostic factors for BC (Ki67, p53, E‐cadherin, HER2). In the last years, it has been shown that variations in the expression of MMPs and TIMPs may contribute to the development of BC. The aim of this pilot work was to study the effects of RT on different MMPs (‐1, ‐2, ‐3, ‐7, ‐8, ‐9, ‐10, ‐12 and ‐13) and TIMPs (‐1 to ‐4), as well as their relationship with other variables related to patient characteristics and tumour biology. A group of 20 BC patients treated with RT were recruited. MMP and TIMP serum levels were analysed by immunoassay before, during and after RT. Our pilot study showed a slight increase in the levels of most MMP and TIMP with RT. However, RT produced a significantly decrease in TIMP‐1 and TIMP‐3 levels. Significant correlations were found between MMP‐3 and TIMP‐4 levels, and some of the variables studied related to patient characteristics and tumour biology. Moreover, MMP‐9 and TIMP‐3 levels could be predictive of RT toxicity. For this reason, MMP‐3, MMP‐9, TIMP‐3 and TIMP‐4 could be used as potential prognostic and predictive biomarkers for BC patients treated with RT.

Using a modified Delphi methodology to gain consensus on the use of dressings in chronic wounds management

OBJECTIVE

Managing chronic wounds is associated with a burden to patients, caregivers, health services and society and there is a lack of clarity regarding the role of dressings in improving outcomes. This study aimed to provide understanding on a range of topics, including: the definition of chronicity in wounds, the burden of illness, clinical outcomes of reducing healing time and the impact of early interventions on clinical and economic outcomes and the role of matrix metalloproteinases (MMPs) in wound healing.

METHOD

A systematic review of the literature was carried out on the role of dressings in diabetic foot ulcer (DFU), and venous leg ulcer (VLU) management strategies, their effectiveness, associated resource use/cost, and quality of life (QoL) impact on patients. From this evidence-base statements were written regarding chronicity in wounds, burden of illness, healing time, and the role of MMPs, early interventions and dressings. A modified Delphi methodology involving two iterations of email questionnaires followed by a face-to-face meeting was used to validate the statements, in order to arrive at a consensus for each. Clinical experts were selected, representing nurses, surgeons, podiatrists, academics, and policy experts.

RESULTS

In the first round, 38/47 statements reached or exceeded the consensus threshold of 80% and none were rejected. According to the protocol, any statement not confirmed or rejected had to be modified using the comments from participants and resubmitted. In the second round, 5/9 remaining statements were confirmed and none rejected, leaving 4 to discuss at the meeting. All final statements were confirmed with at least 80% consensus.

CONCLUSION

This modified Delphi panel sought to gain clarity from clinical experts surrounding the use of dressings in the management of chronic wounds. A full consensus statement was developed to help clinicians and policy makers improve the management of patients with these conditions.

Drug therapies and delivery mechanisms to treat perturbed skin wound healing

Acute wound healing is an orderly process of four overlapping events: haemostasis, inflammation, proliferation and remodelling. A drug delivery system with a temporal control of release could promote each of these events sequentially. However, acute wound healing normally proceeds very well in healthy individuals and there is little need to promote it. In the elderly and diabetics however, healing is often slow and wounds can become chronic and we need to promote their healing. Targeting the events of acute wound healing would not be appropriate for a chronic wound, which have stalled in the proinflammatory phase. They also have many additional problems such as poor circulation, low oxygen, high levels of leukocytes, high reactive oxygen species, high levels of proteolytic enzymes, high levels of proinflammatory cytokines, bacterial infection and high pH. The future challenge will be to tackle each of these negative factors to create a wound environment conducive to healing.

The reality of routine practice: a pooled data analysis on chronic wounds treated with TLC-NOSF wound dressings

OBJECTIVE

A number of randomised controlled trials (RCT) have compared control groups with TLC-NOSF dressings (UrgoStart) on chronic wounds. Our aim was to determine whether the clinical trials' results translate into routine management of such wounds, by pooling the data from real-life observational studies.

METHOD

Observational studies, conducted in France and Germany, evaluating current practices in patients suffering from non-selected chronic wounds treated with a TLC-NOSF dressing were identified. Demographic data, baseline description of wounds and description of their evolution during treatment were extracted and combined. We used two main indicators of clinical outcomes to measure the impact of the TLC-NOSF dressing on this population: time to wound closure and time to 50% reduction of the Pressure Ulcer Scale for Healing (PUSH) score.

RESULTS

In total, data from 10,220 patients were included, with 7903 leg ulcers (LUs), 1306 diabetic foot ulcers (DFUs) and 1011 pressure ulcers (PUs). The overall closure rate was 30.8 % [95 % confidence interval (CI): 29.9-31.7 %]. While the country, patient age, and number of wounds were identified as independent prognosis factors of healing, the most significant were wound duration and baseline area. The delay in initiating TLC-NOSF dressings treatment was also found to be significant. Overall the average time to complete closure was 112.5 days [95%CI: 105.8-119.3] for LUs, 98.1 days [95 %CI: 88.8-107.5] for DFUs and 119.5 days [95%CI: 94.6-144.3] for PUs. Based on a subgroup analysis of the French cohort, time to closure is substantially shorter for wounds treated with the TLC-NOSF dressing as a first-line intervention compared with those where it has been prescribed as a second-line intervention.

CONCLUSION

Compared with available data on time to complete closure of chronic wounds managed by 'standard' care, the data from this pooled data analysis showed healing time is reduced, which is consistent with the results of RCTs on TLC-NOSF. That these data are in agreement with those from the RCTs is testimony to their generalisability and important for routine practice. This indicates that using TLC-NOSF dressings in routine wound management can reduce the healing time of LUs, DFUs and PUs. These data also suggest that the earlier the decision to use this dressing, the shorter the time to closure, whatever the severity and the nature of these chronic wounds.

Inflammation Biomarkers and Correlation to Wound Status After Full-Thickness Skin Grafting

Background: A surgical site infection (SSI) is believed to be the result of an exaggerated inflammatory response. Objective: Examine the relationship between clinical status and inflammation biomarkers in full-thickness skin grafting wounds. Methods: Twenty patients planned for facial full-thickness skin grafting were enrolled. A week after surgery, all graft wounds were clinically assessed using a 3-step scale for inflammation (low, moderate, high). All wounds were swabbed for routine microbiological analysis and assessment of numbers of aerobic bacteria. Tie-over dressings from all patients were collected and used for wound fluid extraction and subsequent analysis of MMPs, cytokines, and NF-κB inducing activity. Results: Wounds with a high degree of inflammation contained increased total MMP activity (P ≤ 0.05) in their corresponding fluids. Likewise, the level of the cytokines IL-1ß, IL-8, IL-6, TNF-α was analyzed, and particularly IL-1ß was discriminatory for highly inflamed wounds (P ≤ 0.01). Moreover, bacterial loads were increased in highly inflamed wounds compared to wounds with a low degree of inflammation (P ≤ 0.01). NF-κB activation in the monocytic cell line THP-1 was significantly higher when these cells were stimulated by wound fluids with a high degree of inflammation (P ≤ 0.01). Growth of S. aureus in wounds did not vary between wounds with different degrees of inflammation (chi-square 3.8, P = 0.144). Conclusion: Biomarkers analyzed from tie-over dressings correlated to clinical wound healing in full-thickness skin grafting.

Optimal wound closure of diabetic foot ulcers with early initiation of TLC-NOSF treatment: post-hoc analysis of Explorer

Objective:

In March 2018, the Explorer study, an international, double-blind, randomised controlled trial (RCT), established that adding a TLC-NOSF (UrgoStart Contact, Laboratoires Urgo, France) dressing to good local standard of care (SoC) significantly and substantially increases wound closure and reduces the healing time of neuroischaemic diabetic foot ulcers (DFU). Besides the TLC-NOSF treatment, the wound duration was the only other covariate that had an influence on the wound closure rate in the regression model used in the original study. The purpose of this work was to further document the impact of wound duration on the healing outcomes of the DFUs included in the Explorer study and to discuss complementary pragmatic observations on the TLC-NOSF effect.

Method:

In this post-hoc analysis of the Explorer data, the wound closure rates by week 20 are reported for the global cohort (n=240, Intention-to-treat population) and for the treated (n=126) and control groups (n=114) according to DFU duration and location.

Results:

For the combined group, wound closure rates decreased with the increase of wound duration at baseline (from 57% in wounds ≤2 months to 19% in wounds >11 months). Whatever the wound duration subgroups analysed, higher closure rates were reported in the TLC-NOSF group than in the control group. However, the maximal difference between the two treatments was reported in wounds with a duration of ≤2 months (71% versus 41%, 30 percentage points difference, Relative Risk 1.7, 95% Confidence Interval 1.1 to 2.8). Regarding wound location subgroup analyses, the outcomes were always in favour of the TLC-NOSF treatment, with closure rates ranging between 43% and 61% within the TLC-NOSF group, and between 25% and 40% within the control group.

Conclusion:

This clinical evidence supports that treating DFUs with TLC-NOSF dressing and good SoC results in higher wound closure rates than with a neutral dressing and the same good standard of care, whatever the duration and the location of the treated wounds. However, the earlier the TLC-NOSF dressing is initiated in DFU treatment, the greater the benefits.

Targeting MMP-9 in Diabetic Foot Ulcers

Diabetic foot ulcers (DFUs) are significant complications of diabetes and an unmet medical need. Matrix metalloproteinases (MMPs) play important roles in the pathology of wounds and in the wound healing process. However, because of the challenge in distinguishing active MMPs from the two catalytically inactive forms of MMPs and the clinical failure of broad-spectrum MMP inhibitors in cancer, MMPs have not been a target for treatment of DFUs until recently. This review covers the discovery of active MMP-9 as the biochemical culprit in the recalcitrance of diabetic wounds to healing and targeting this proteinase as a novel approach for the treatment of DFUs. Active MMP-8 and MMP-9 were observed in mouse and human diabetic wounds using a batimastat affinity resin and proteomics. MMP-9 was shown to play a detrimental role in diabetic wound healing, whereas MMP-8 was beneficial. A new class of selective MMP-9 inhibitors shows clinical promise for the treatment of DFUs.

Metalloproteinases in chronic and acute wounds: A systematic review and meta-analysis

A systematic review and meta-analysis were undertaken in order to explore the influence of matrix metalloproteinases and their diagnostic methods in chronic and acute wounds. Searches were conducted in the PubMed (Medline) and Embase (Elsevier) databases from inception to late November 2017. We included clinical trials enrolling patients with cutaneous chronic and acute wounds where a validated diagnostic method was employed for metalloproteinases. We excluded in vitro, animal or preclinical studies, nonoriginal articles, and studies without available data for analysis. In addition, references of narrative and systematic reviews were scrutinized for additional articles. Eight studies met the inclusion criteria. Results revealed that the most frequently determined matrix metalloproteinases were MMP-2 and MMP-9, and were found in 54.5% of wounds. MMP-9 was present in more than 50% of the chronic wounds with a range from 37 to 78%. However, metalloproteinases were found in only 20% of acute wounds, and other types of metalloproteinases were also observed (MMP-2 and MMP-3). On the basis of the available evidence, high levels of metalloproteinases have been correlated with significantly delayed wound healing in wounds of a variety of etiologies.

Iron and iron-dependent reactive oxygen species in the regulation of macrophages and fibroblasts in non-healing chronic wounds

Chronic wounds pose a stern challenge to health care systems with growing incidence especially in the aged population. In the presence of increased iron concentrations, recruitment of monocytes from the circulation and activation towards ROS and RNS releasing M1 macrophages together with the persistence of senescent fibroblasts at the wound site are significantly enhanced. This unrestrained activation of pro-inflammatory macrophages and senescent fibroblasts has increasingly been acknowledged as main driver causing non-healing wounds. In a metaphor, macrophages act like stage directors of wound healing, resident fibroblasts constitute main actors and increased iron concentrations are decisive parts of the libretto, and - if dysregulated - are responsible for the development of non-healing wounds. This review will focus on recent cellular and molecular findings from chronic venous leg ulcers and diabetic non-healing wounds both constituting the most common pathologies often resulting in limb amputations of patients. This not only causes tremendous suffering and loss of life quality, but is also associated with an increase in mortality and a major socio-economic burden. Despite recent advances, the underlying molecular mechanisms are not completely understood. Overwhelming evidence shows that reactive oxygen species and the transition metal and trace element iron at pathological concentrations are crucially involved in a complex interplay between cells of different histogenetic origin and their extracellular niche environment. This interplay depends on a variety of cellular, non-cellular biochemical and cell biological mechanisms. Here, we will highlight recent progress in the field of iron-dependent regulation of macrophages and fibroblasts and related pathologies linked to non-healing chronic wounds.

Protease activity as a prognostic factor for wound healing in venous leg ulcers

BACKGROUND

Venous leg ulcers (VLUs) are a common type of complex wound that have a negative impact on people's lives and incur high costs for health services and society. It has been suggested that prolonged high levels of protease activity in the later stages of the healing of chronic wounds may be associated with delayed healing. Protease modulating treatments have been developed which seek to modulate protease activity and thereby promote healing in chronic wounds.

OBJECTIVES

To determine whether protease activity is an independent prognostic factor for the healing of venous leg ulcers.

SEARCH METHODS

In February 2018, we searched the following databases: Cochrane Central Register of Controlled Trials (CENTRAL), Ovid MEDLINE, Ovid Embase and CINAHL.

SELECTION CRITERIA

We included prospective and retrospective longitudinal studies with any follow-up period that recruited people with VLUs and investigated whether protease activity in wound fluid was associated with future healing of VLUs. We included randomised controlled trials (RCTs) analysed as cohort studies, provided interventions were taken into account in the analysis, and case-control studies if there were no available cohort studies. We also included prediction model studies provided they reported separately associations of individual prognostic factors (protease activity) with healing. Studies of any type of protease or combination of proteases were eligible, including proteases from bacteria, and the prognostic factor could be examined as a continuous or categorical variable; any cut-off point was permitted. The primary outcomes were time to healing (survival analysis) and the proportion of people with ulcers completely healed; the secondary outcome was change in ulcer size/rate of wound closure. We extracted unadjusted (simple) and adjusted (multivariable) associations between the prognostic factor and healing.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed studies for inclusion at each stage, and undertook data extraction, assessment of risk of bias and GRADE assessment. We collected association statistics where available. No study reported adjusted analyses: instead we collected unadjusted results or calculated association measures from raw data. We calculated risk ratios when both outcome and prognostic factor were dichotomous variables. When the prognostic factor was reported as continuous data and healing outcomes were dichotomous, we either performed regression analysis or analysed the impact of healing on protease levels, analysing as the standardised mean difference. When both prognostic factor and outcome were continuous data, we reported correlation coefficients or calculated them from individual participant data.We displayed all results on forest plots to give an overall visual representation. We planned to conduct meta-analyses where this was appropriate, otherwise we summarised narratively.

MAIN RESULTS

We included 19 studies comprising 21 cohorts involving 646 participants. Only 11 studies (13 cohorts, 522 participants) had data available for analysis. Of these, five were prospective cohort studies, four were RCTs and two had a type of case-control design. Follow-up time ranged from four to 36 weeks. Studies covered 10 different matrix metalloproteases (MMPs) and two serine proteases (human neutrophil elastase and urokinase-type plasminogen activators). Two studies recorded complete healing as an outcome; other studies recorded partial healing measures. There was clinical and methodological heterogeneity across studies; for example, in the definition of healing, the type of protease and its measurement, the distribution of active and bound protease species, the types of treatment and the reporting of results. Therefore, meta-analysis was not performed. No study had conducted multivariable analyses and all included evidence was of very low certainty because of the lack of adjustment for confounders, the high risk of bias for all studies except one, imprecision around the measures of association and inconsistency in the direction of association. Collectively the research indicated complete uncertainty as to the association between protease activity and VLU healing.

AUTHORS' CONCLUSIONS

This review identified very low validity evidence regarding any association between protease activity and VLU healing and there is complete uncertainty regarding the relationship. The review offers information for both future research and systematic review methodology.

Descriptive vs mechanistic scientific approach to study wound healing and its inhibition: Is there a value of translational research involving human subjects?

The clinical field of wound healing is challenged by numerous hurdles. Not only are wound-healing disorders complex and multifactorial, but the corresponding patient population is diverse, often elderly and burdened by multiple comorbidities such as diabetes and cardiovascular disease. The care of such patients requires a dedicated, multidisciplinary team of physicians, surgeons, nurses and scientists. In spite of the critical clinical need, it has been over 15 years since a treatment received approval for efficacy by the FDA in the United States. Among the reasons contributing to this lack of effective new treatment modalities is poor understanding of mechanisms that inhibit healing in patients. Additionally, preclinical models do not fully reflect the disease complexity of the human condition, which brings us to a paradox: if we are to use a "mechanistic" approach that favours animal models, we can dissect specific mechanisms using advanced genetic, molecular and cellular technologies, with the caveat that it may not be directly applicable to patients. Traditionally, scientific review panels, for either grant funding or manuscript publication purposes, favour such "mechanistic" approaches whereby human tissue analyses, deemed "descriptive" science, are characterized as a "fishing expedition" and are considered "fatally flawed." However, more emerging evidence supports the notion that the use of human samples provides significant new knowledge regarding the molecular and cellular mechanisms that control wound healing and contribute to inhibition of the process in patients. Here, we discuss the advances, benefits and challenges of translational research in wound healing focusing on human subject research.

Scarring vs. functional healing: Matrix-based strategies to regulate tissue repair

All vertebrates possess mechanisms to restore damaged tissues with outcomes ranging from regeneration to scarring. Unfortunately, the mammalian response to tissue injury most often culminates in scar formation. Accounting for nearly 45% of deaths in the developed world, fibrosis is a process that stands diametrically opposed to functional tissue regeneration. Strategies to improve wound healing outcomes therefore require methods to limit fibrosis. Wound healing is guided by precise spatiotemporal deposition and remodelling of the extracellular matrix (ECM). The ECM, comprising the non-cellular component of tissues, is a signalling depot that is differentially regulated in scarring and regenerative healing. This Review focuses on the importance of the native matrix components during mammalian wound healing alongside a comparison to scar-free healing and then presents an overview of matrix-based strategies that attempt to exploit the role of the ECM to improve wound healing outcomes.

Sucrose octasulfate dressing versus control dressing in patients with neuroischaemic diabetic foot ulcers (Explorer): an international, multicentre, double-blind, randomised, controlled trial

BACKGROUND

Diabetic foot ulcers are serious and challenging wounds associated with high risk of infection and lower-limb amputation. Ulcers are deemed neuroischaemic if peripheral neuropathy and peripheral artery disease are both present. No satisfactory treatment for neuroischaemic ulcers currently exists, and no evidence supports one particular dressing. We aimed to assess the effect of a sucrose octasulfate dressing versus a control dressing on wound closure in patients with neuroischaemic diabetic foot ulcers.

METHODS

We did a randomised, double-blind clinical trial (Explorer) in 43 hospitals with specialised diabetic foot clinics in France, Spain, Italy, Germany, and the UK. Eligible participants were inpatients or outpatients aged 18 years or older with diabetes and a non-infected neuroischaemic diabetic foot ulcer greater than 1 cm² and of grade IC or IIC (as defined by the University of Texas Diabetic Wound Classification system). We excluded patients with a severe illness that might lead to them discontinuing the trial and those who had surgical revascularisation in the month before study entry. We randomly assigned participants (1:1) via a computer-generated randomisation procedure (concealed block size two); stratified by study centre and wound area (1-5 cm² and 5-30 cm²), to treatment with either a sucrose octasulfate wound dressing or a control dressing (the same dressing without sucrose octasulfate) for 20 weeks. Both groups otherwise received the same standard of care for a 2-week screening period before randomisation and throughout the 20-week trial. Dressings were applied by nursing staff (or by instructed relatives for some outpatients). Frequencies of dressing changes were decided by the investigator on the basis of the clinical condition of the wound. Patients were assessed 2 weeks after randomisation, then monthly until week 20 or occurrence of wound closure. The primary outcome, assessed by intention-to-treat, was proportion of patients with wound closure at week 20. This trial is registered with ClinicalTrials.gov, number NCT01717183.

FINDINGS

Between March 21, 2013, and March 31, 2016, we randomly assigned 240 individuals to treatment: 126 to the sucrose octasulfate dressing and 114 to the control dressing. After 20 weeks, wound closure occurred in 60 patients (48%) in the sucrose octasulfate dressing group and 34 patients (30%) in the control dressing group (18 percentage points difference, 95% CI 5-30; adjusted odds ratio 2·60, 95% CI 1·43-4·73; p=0·002). In both groups, the most frequent adverse events were infections of the target wound: 33 wound infections in 25 (20%) patients of 126 in the sucrose octasulfate dressing group and 36 in 32 (28%) patients of 114 in the control dressing group. Minor amputations not affecting the wound site were also reported in one (1%) patient in the sucrose octasulfate dressing group and two (2%) patients in the control dressing group. Three (2%) patients assigned to the sucrose octasulfate dressing and four (4%) assigned to the control dressing died, but none of the deaths were related to treatment, procedure, wound progression, or subsequent to amputation.

INTERPRETATION

A sucrose octasulfate dressing significantly improved wound closure of neuroischaemic diabetic foot ulcers without affecting safety after 20 weeks of treatment along with standard care. These findings support the use of sucrose octasulfate dressing as a local treatment for neuroischaemic diabetic foot ulcers.

FUNDING

Laboratoires Urgo Medical.

Role of Mitochondrial Reactive Oxygen Species in the Activation of Cellular Signals, Molecules, and Function

Mitochondria are a major source of intracellular energy and reactive oxygen species in cells, but are also increasingly being recognized as a controller of cell death. Here, we review evidence of signal transduction control by mitochondrial superoxide generation via the nuclear factor-κB (NF-κB) and GATA signaling pathways. We have also reviewed the effects of ROS on the activation of MMP and HIF. There is significant evidence to support the hypothesis that mitochondrial superoxide can initiate signaling pathways following transport into the cytosol. In this study, we provide evidence of TATA signal transductions by mitochondrial superoxide. Oxidative phosphorylation via the electron transfer chain, glycolysis, and generation of superoxide from mitochondria could be important factors in regulating signal transduction, cellular homeostasis, and cell death.

The Versican G1 Fragment and Serum-Derived Hyaluronan-Associated Proteins Interact and Form a Complex in Granulation Tissue of Pressure Ulcers

The hyaluronan (HA)-rich extracellular matrix plays dynamic roles during tissue remodeling. Versican and serum-derived HA-associated protein (SHAP), corresponding to the heavy chains of inter-α-trypsin inhibitor, are major HA-binding molecules in remodeling processes, such as wound healing. Versican G1-domain fragment (VG1F) is generated by proteolysis and is present in either remodeling tissues or the mature dermis. However, the macrocomplex formation of VG1F has not been clarified. Therefore, we examined the VG1F-containing macrocomplex in pressure ulcers characterized by chronic refractory wounds. VG1F colocalized with SHAP-HA in specific regions of the granulation tissue but not with fibrillin-1. A unique VG1F-SHAP-HA complex was isolated from granulation tissues using gel filtration chromatography and subsequent cesium chloride-gradient ultracentrifugation under dissociating conditions. Consistent with this molecular composition, recombinant versican G1, but not versican G3, interacted with the two heavy chains of inter-α-trypsin inhibitor. The addition of recombinant VG1 in fibroblast cultures enhanced VG1F-SHAP-HA complex deposition in the pericellular extracellular matrix. Comparison with other VG1F-containing macrocomplexes, including dermal VG1F aggregates, versican-bound microfibrils, and intact versican, highlighted the tissue-specific organization of HA-rich extracellular matrix formation containing versican and SHAP. The VG1F-SHAP-HA complex was specifically detected in the edematous granulation tissues of human pressure ulcers and in inflamed stages in a mouse model of moist would healing, suggesting that the complex provides an HA-rich matrix suitable for inflammatory reactions.

[Pathogen analysis in patients with diabetic foot osteomyelitis using 16S rRNA high-throughput sequencing]

OBJECTIVE

To analyze the characteristics of pathogenic microorganisms in the infected bone tissues in patients with diabetic foot osteomyelitis (DFO) using 16S rRNA high-throughput sequencing to facilitate rapid and accurate detection of pathogens and effective infection control.

METHODS

Between September, 2016 and April, 2017, 16 patients with DFO were admitted in our department and infected bone specimens were obtained during debridement. The pathogenic microorganisms in the specimens were identified using both 16S rRNA high-throughput sequencing and automatic blood culture analyzer, and the characteristics of the microflora were analyzed based on 16S rRNA sequencing data in comparison with the results of blood culture.

RESULTS

The results of 16S rRNA sequencing showed that bone tissues of DFO contained diverse and uniformly distributed pathogenic organisms, among which 20 (87%) dominant genera were identified with Prevotella as the most abundant pathogen. Both 16S rRNA sequencing and routine culture results suggested the domination of gram-negative bacteria among the pathogens in DFO bone tissues. 16S rRNA sequencing, compared with routine culture, yielded a higher positivity rate (100% vs 88.24%) and detected a greater average number of pathogens (12.56 vs 1.50) and a higher proportion of gram-negative bacteria (67.16% vs 50.00%) in the samples. 16S rRNA sequencing detected nearly all the pathogens identified by routine culture except for Escherichia coli, Serratia marcescens and Enterobacter cloaca, and identified 13 genera that failed to be detected by routine culture, including the obligate or strict anaerobes Anaerococcus, Veillonella, Bacteroides, Fusobacterium, Porphyromonas, Finegoldia, Prevotella, Peptostreptococcus, Parvimonas, Peptoniphilus and Bulleidia. Routine culture did not detect any anaerobes in the samples but identified multidrug-resistant strains in as many as 58.33% of the pathogens.

CONCLUSIONS

16S rRNA high-throughput sequencing is capable of demonstrating the diversity and abundance of microflora in DFO bone tissues, where diverse and uniformly distributed pathogens can be detected with a discrete distribution of the dominant genera, most of which are gram-negative. Compared with routine culture method, 16S rRNA sequencing allows more convenient and accurate identification of the pathogens (especially gram-negative bacteria and anaerobes), and can be useful in clinical decision on appropriate treatment of DFO.

Proteolytic signatures define unique thrombin-derived peptides present in human wound fluid in vivo

The disease burden of failing skin repair and non-healing ulcers is extensive. There is an unmet need for new diagnostic approaches to better predict healing activity and wound infection. Uncontrolled and excessive protease activity, of endogenous or bacterial origin, has been described as a major contributor to wound healing impairments. Proteolytic peptide patterns could therefore correlate and “report” healing activity and infection. This work describes a proof of principle delineating a strategy by which peptides from a selected protein, human thrombin, are detected and attributed to proteolytic actions. With a particular focus on thrombin-derived C-terminal peptides (TCP), we show that distinct peptide patterns are generated in vitro by the human S1 peptidases human neutrophil elastase and cathepsin G, and the bacterial M4 peptidases Pseudomonas aeruginosa elastase and Staphylococcus aureus aureolysin, respectively. Corresponding peptide sequences were identified in wound fluids from acute and non-healing ulcers, and notably, one peptide, FYT21 (FYTHVFRLKKWIQKVIDQFGE), was only present in wound fluid from non-healing ulcers colonized by P. aeruginosa and S. aureus. Our result is a proof of principle pointing at the possibility of defining peptide biomarkers reporting distinct proteolytic activities, of potential implication for improved diagnosis of wound healing and infection.

Quality of life in patients with leg ulcers: results from CHALLENGE, a double-blind randomised controlled trial

OBJECTIVE

We recently showed the superiority of a matrix metalloproteinase (MMP) modulating dressing (foam impregnated with NOSF, nano-oligosaccharide factor) compared with a lipidocolloid matrix (TLC) control dressing in median wound area reduction (WAR). Here we report the results from the same study assessing the performance and safety of TLC-NOSF in the local management of venous leg ulcers (VLUs) or mixed leg ulcers and determining its impact on the patient's health-related quality of life (HRQoL).

METHOD

A superiority randomised double-blind controlled trial was conducted on patients presenting with a non-infected leg ulcer (VLUs or mixed leg ulcers) of predominantly venous origin (ABPI >0.8), with a surface area ranging from 5 to 50cm² and a duration of 6 to 36 months. Patients were randomly allocated to either the TLC-NOSF matrix foam (UrgoStart) dressing group or to the neutral TLC foam dressing group (UrgoTul Absorb). All received appropriate compression therapy and the wounds were assessed blindly (clinical examination, wound area tracing and photographic record) every 2 weeks for a period of 8 weeks, or until complete closure. A secondary endpoint, described here, was the patient's HRQoL, documented by the patient, through the EuroQol 5D tool (EQ-5D) questionnaire and visual analogue scale (VAS).

RESULTS

In total, 187 patients were randomised to either the TLC-NOSF group (n=94) or the control dressing group (n=93). The two groups were well balanced at baseline with regard to wound and patient characteristics. In the HRQoL questionnaire (EQ-5D), the pain/discomfort and anxiety/depression dimensions were significantly improved in the TLC-NOSF group versus the control one (pain/discomfort: 1.53±0.53 versus 1.74±0.65; p=0.022, and anxiety/depression: 1.35±0.53 versus 1.54±0.60, p=0.037). The VAS score was better in the test group compared with the control group (72.1±17.5 versus 67.3±18.7, respectively), without reaching significance (p=0.072). Acceptability and tolerance of the two products were similar in both groups.

CONCLUSION

The double-blind clinical trial has demonstrated that the TLC-NOSF matrix dressing promotes faster healing of VLUs and mixed leg ulcers and significantly reduces the pain/discomfort and anxiety/depression experienced by the patients. These results suggest that acceleration of VLU healing could improve the HRQoL of the patients and reduced the emotional and social burden of these chronic wounds.

Using biomaterials to rewire the process of wound repair

Wound healing is one of the most complex processes that our bodies must perform. While our ability to repair wounds is often taken for granted, conditions such as diabetes, obesity, or simply old age can significantly impair this process. With the incidence of all three predicted to continue growing into the foreseeable future, there is an increasing push to develop strategies that facilitate healing. Biomaterials are an attractive approach for modulating all aspects of repair, and have the potential to steer the healing process towards regeneration. In this review, we will cover recent advances in developing biomaterials that actively modulate the process of wound healing, and will provide insight into how biomaterials can be used to simultaneously rewire multiple phases of the repair process.