Reduction of diabetic foot ulcer healing times through use of advanced treatment modalities

Clinical Evaluation of AMNIODERM+® Wound Dressing Containing Non-Viable Human Amniotic Membrane: Retrospective-Perspective Clinical Trial

Chronic wounds result from the body's inability to heal, causing pain, pathogen entry, limited treatment options, and societal burden. Diabetic foot ulcers are particularly challenging, often leading to severe complications like leg amputation. A clinical study tested AMNIODERM+®, a new device with a lyophilized human amniotic membrane (HAM), on chronic diabetic foot ulcers. Participants had diabetic neuropathic or neuroischemic leg wounds (2-16 cm2) unhealed by 20% after six weeks of standard care. This study showed significant wound healing improvements with AMNIODERM+®. The median wound size reduction after 12 weeks was 95.5%, far exceeding the null hypothesis of 20% change. Additionally, 65% of patients achieved complete ulceration healing, surpassing the 50% efficacy requirement. The median time to full closure was 11.4 weeks, with the proportion of completely healed patients rising progressively, reaching 55% by week 11. These findings, from the clinical trial "Freeze-dried amniotic membrane in the treatment of nonhealing wounds", suggest AMNIODERM+® as a promising future treatment for chronic diabetic foot ulcers. The published results were obtained as part of a clinical trial entitled "Freeze-dried amniotic membrane in the treatment of nonhealing wounds: a single-arm, retrospectively-perspective clinical trial", EUDAMED Nr. CIV-SK-22-10-041146.

The Efficacy of Negative Pressure Wound Therapy (NPWT) on Healing of Diabetic Foot Ulcers: A Literature Review

BACKGROUND

Diabetes mellitus is a complex disorder that requires continuous management to control blood sugar levels and prevent complications. Diabetic foot ulcers (DFU) are the most common complication in diabetic patients. A popular therapy modality with considerable advantages in the management of diabetic foot ulcers today is negative pressure wound therapy (NPWT).

OBJECTIVE

This study aimed to review related articles about the efficacy as well as the complications or adverse effects of using NPWT on the healing of DFUs.

METHODS

Searching English databases from PubMed, Ebscohost, Proquest and Science Direct was done to identify relevant citations published between January 2017 and January 2022. A combination of terms was used with the boolean formulation of "negative pressure wound therapy OR NPWT" OR "vacuum-assisted closure or VAC" AND "diabetic foot ulcers OR diabetic foot wound" AND "wound healing" AND "Conventional dressings" and map terms were also used for the subject heading. Some potentially relevant citations of articles from the bibliographies are also reviewed.

RESULTS

This study included 8 related articles consisting of 6 RCTs, 1 cohort study and 1 Quasy experimental study. There were various methodological techniques for using NPWT and outcome measures among studies. The results of this literature review showed that NPWT was more efficacious than the other conventional or advanced moist dressings. This therapy revealed a faster healing time with complete wound healing and formation of granulation tissue and reduction in wound size. The complications or adverse effects of NPWT, such as amputation rate, bleeding and pain, were not different from conventional or advanced moist dressings, though.

CONCLUSION

NPWT was more efficacious than other conventional or advanced moist dressings for the healing of DFUs. However, complications or adverse effects of using this therapy showed no significant difference with other conventional or advanced moist dressings.

The effect of Klotho protein complexed with nanomaterials on bone mesenchymal stem cell performance in the treatment of diabetic ischaemic ulcer

A lack of angiogenesis is the key problem in the healing of diabetic foot ulcers. Stem cells have already been proven to have a high potential for angiogenesis. The most important aspects of stem cell therapy are improving the microenvironment, cell homing and continuous factor stimulation. We investigated the effect of Klotho protein to heal wounds by promoting the proliferation and migration of bone mesenchymal stem cells and endothelial cells in vitro. Based on the above study, we produced a compound material by using poly(lactic-co-glycolic acid) (PLGA), chitosan microspheres and gelatin through electro spining technology. The structure of the compound material, just like a sandwich, is that two pieces of PLGA nanofiber films clamped gelatin film which contained chitosan microspheres. In the in vitro release experiment, we could detect the release of Klotho after seven days in the compound material, but the release time was approximately 40 hours for the chitosan microspheres. After seeded bone mesenchymal stem cells (BMSCs) on the surface of the compound material, we observed morphologies of the chitosan microsphere, the PLGA nanofiber and BMSCs by scanning electron microscopy. The nanofiber mesh biological tissue materials could supply an appropriate microenvironment and cell factors for the survival of BMSCs. Compared with the control group, the biological tissue material seeded with BMSCs significantly promoted angiogenesis in the lower limb of diabetic C57BL/6J mice and accelerated diabetic foot wound healing. The compound biomaterial which could continuously stimulate BMSCs through releasing Klotho protein could accelerate wound healing in the diabetic foot and other ischemic ulcers.

Protease-Triggered Release of Stabilized CXCL12 from Coated Scaffolds in an Ex Vivo Wound Model

Biomaterials are designed to improve impaired healing of injured tissue. To accomplish better cell integration, we suggest to coat biomaterial surfaces with bio-functional proteins. Here, a mussel-derived surface-binding peptide is used and coupled to CXCL12 (stromal cell-derived factor 1α), a chemokine that activates CXCR4 and consequently recruits tissue-specific stem and progenitor cells. CXCL12 variants with either non-releasable or protease-mediated-release properties were designed and compared. Whereas CXCL12 was stabilized at the N-terminus for protease resistance, a C-terminal linker was designed that allowed for specific cleavage-mediated release by matrix metalloproteinase 9 and 2, since both enzymes are frequently found in wound fluid. These surface adhesive CXCL12 derivatives were produced by expressed protein ligation. Functionality of the modified chemokines was assessed by inositol phosphate accumulation and cell migration assays. Increased migration of keratinocytes and primary mesenchymal stem cells was demonstrated. Immobilization and release were studied for bioresorbable PCL-co-LC scaffolds, and accelerated wound closure was demonstrated in an ex vivo wound healing assay on porcine skin grafts. After 24 h, a significantly improved CXCL12-specific growth stimulation of the epithelial tips was already observed. The presented data display a successful application of protein-coated biomaterials for skin regeneration.

Recent perspectives of nanotechnology in burn wounds management: a review

OBJECTIVE

The burden of the management of problematic skin wounds characterised by a compromised skin barrier is growing rapidly. Almost six million patients are affected in the US alone, with an estimated market of $25 billion annually. There is an urgent requirement for efficient mechanism-based treatments and more efficacious drug delivery systems. Novel strategies are needed for faster healing by reducing infection, moisturising the wound, stimulating the healing mechanisms, speeding up wound closure and reducing scar formation.

METHODS

A systematic review of qualitative studies was conducted on the recent perspectives of nanotechnology in burn wounds management. Pubmed, Scopus, EMBASE, CINAHL and PsychINFO databases were all systematically searched. Authors independently rated the reporting of the qualitative studies included. A comprehensive literature search was conducted covering various resources up to 2018-2019. Traditional techniques aim to simply cover the wound without playing any active role in wound healing. However, nanotechnology-based solutions are being used to create multipurpose biomaterials, not only for regeneration and repair, but also for on-demand delivery of specific molecules. The chronic nature and associated complications of nonhealing wounds have led to the emergence of nanotechnology-based therapies that aim at facilitating the healing process and ultimately repairing the injured tissue.

CONCLUSION

Nanotechnology-based therapy is in the forefront of next-generation therapy that is able to advance wound healing of hard-to-heal wounds. In this review, we will highlight the developed nanotechnology-based therapeutic agents and assess the viability and efficacy of each treatment. Herein we will explore the unmet needs and future directions of current technologies, while discussing promising strategies that can advance the wound-healing field.

Managing Diabetic Foot Ulcers: Pharmacotherapy for Wound Healing

Historically, there has been a scarcity of evidence-based topical therapy to hasten the healing of diabetic foot ulcers. But recently new evidence-based treatments have emerged from multicentre, randomised, controlled trials. This article highlights those trials, and describes the current pharmacological management of the diabetic foot ulcer and the advances that have been made in wound therapy to date. It provides an overview of topical and systemic pharmacotherapies in current use and those in development for future use in managing the diabetic foot. For each treatment, proposed mechanisms of action and evidence available to support their clinical use are presented. There is supporting randomised, controlled evidence for sucrose octasulfate in the treatment of neuro-ischaemic ulcers, and multi-layered patch of autologous leucocytes, platelets and fibrin in ulcers with or without ischaemia. There is also evidence for placentally derived products and for topical and systemic oxygen therapy in the healing of diabetic foot ulcers. Growth factors, bio-engineered tissues, stem cell therapy, gene therapy and peptide therapy also have some supporting evidence in the healing of diabetic foot ulcers. Nonsurgical debriding agents may be useful when the optimum approach of sharp debridement is not possible, and immunomodulators may be helpful for their antimicrobial effects, but robust data is still required to strengthen the case for general use. The review does not cover antimicrobials as their primary role are as anti-infectives and not in wound healing. The development of nanotechnology has created a means of prolonging the bioavailability of target molecules at the wound site, with the use of glass/hydrogel nanoparticles, polyethylene glycol and hyaluronic acid. Looking forward, novel therapies, including traction force-activated payloads, local delivery of short-interfering RNA and finally hydrogels incorporating bioactive agents or cells may provide possibilities for pharmacotherapy in the future.

Autologous platelet-rich gel and continuous vacuum sealing drainage for the treatment of patients with diabetic foot ulcer: Study Protocol

BACKGROUND

Research focusing on the efficacy of autologous platelet-rich gel (APRG) and continuous vacuum sealing drainage (CVSD) for diabetic foot ulcer (DFU) is increasing. Despite increasing knowledge on this theme, its results remain inconsistent. Thus, we will provide insight into the efficacy of APRG and CVSD for patients with DFU.

METHODS

We will search electronic databases of MEDILINE, EMBASE, Cochrane Library, CINAHL, AMED, Chinese Biomedical Literature Database, and China National Knowledge Infrastructure from inception to October 1, 2019. No language limitation is utilized to these databases. Two authors will independently perform study selection, data extraction, and risk of bias assessment. Disagreements between 2 authors will be solved through discussion with a third author.

RESULTS

The efficacy and safety of APRG and CVSD for patients with DFU will be assessed by the time to complete healing, proportion of ulcers healed within trial period, change of size of ulcer, health-related quality of life, patient length of hospital stay, and adverse events.

CONCLUSION

The results of this study will provide helpful evidence of APRG and CVSD for patients with DFU.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42019153289.

Hydrogel-Based Strategies to Advance Therapies for Chronic Skin Wounds

Chronic skin wounds are the leading cause of nontraumatic foot amputations worldwide and present a significant risk of morbidity and mortality due to the lack of efficient therapies. The intrinsic characteristics of hydrogels allow them to benefit cutaneous healing essentially by supporting a moist environment. This property has long been explored in wound management to aid in autolytic debridement. However, chronic wounds require additional therapeutic features that can be provided by a combination of hydrogels with biochemical mediators or cells, promoting faster and better healing. We survey hydrogel-based approaches with potential to improve the healing of chronic wounds by reviewing their effects as observed in preclinical models. Topics covered include strategies to ablate infection and resolve inflammation, the delivery of bioactive agents to accelerate healing, and tissue engineering approaches for skin regeneration. The article concludes by considering the relevance of treating chronic skin wounds using hydrogel-based strategies.

Efficacy and safety of platelet-rich plasma in treating cutaneous ulceration: A meta-analysis of randomized controlled trials

BACKGROUND

The biological mechanisms underlying the use of platelet-rich plasma (PRP), as well as the efficacy and possible adverse effects of PRP, have not yet been fully elucidated. Prior studies have evaluated PRP for cutaneous ulceration. However, the benefits from PRP still remain controversial and few have assessed the effects of ulceration etiologies. The purpose of our study is to determine the efficacy and safety of PRP and which kind of ulcer is more suitable for PRP by analyzing the effects of PRP on ulcers with different causes.

METHODS

A comprehensive search was performed to identify randomized controlled trials (RCTs) regarding the application of PRP from PubMed, EMBASE, Scopus, and the Cochrane Library. The data were analyzed using Review Manager 5.3.

RESULTS

A total of nineteen RCTs (909 patients) were included. In contrast with conventional treatments, PRP achieved higher healing rate, higher percentage of area reduction, and smaller final area in vascular ulcers. However, the advantage disappeared in diabetic and pressure ulcers. Concerning adverse events, PRP showed lower incidence in the short term, but higher in the long term. No significant differences were found in ulcer closure velocity and healing time.

CONCLUSION

Platelet-rich plasma effectiveness and safety in treating cutaneous ulceration depend on what is the ulceration etiology. For diabetic ulcers, PRP showed no satisfactory results suggesting that PRP may not be suitable for diabetic patients. However, PRP could be efficient and more beneficial for vascular ulcers and effects on pressure ulcers remain unclear. Thus, PRP option should be carefully considered for each patient in accordance with their ulceration etiologies.

ADIE - Nursing Interventions of Diabetic Foot Ulcer: An Integrative Review of the Literature

BACKGROUND AND AIMS

Diabetic foot ulcer is recognized as a consequence of peripheral neuropathy and peripheral arterial disease amid individuals with diabetes. As is well known, this situation still remains a crucial problem in nursing practice. Available studies describing an algorithm of inter- related nursing interventions concerned with diabetic foot ulcers are limited. Therefore, this integrative review was aimed to present evidence-based practice for overcoming the complications of diabetic foot ulcer as well as preventing lower extremity amputation.

METHODS

This integrative review retrieved scientific literature from PubMed, CINAHL, ProQuest, SAGE Publishing and ScienceDirect databases as published from 2008 to 2017. Thirty-seven studies that met the inclusion criteria were included in this study.

RESULTS

Our findings present that neurologic and circulatory assessments were considered as primary steps prior to conducting interventions. Formulating a diagnosis based upon the assessment results is a principal part to determine appropriate interventions. Multiple experimental studies displayed the effectiveness of certain interventions consist of applying wound cleansing, advanced modern wound dressing, topical therapy, offloading, intensive diabetes education and advanced treatment modalities. Hemoglobin A1c, high-density lipoprotein, procalcitonin, the potential of hydrogen of wound fluid, wound size, neurological and circulatory status were determined as the outcomes measurement which must be correctly evaluated.

CONCLUSION

This review contributes an algorithm for intervening diabetic foot ulcer thereby generating the given name: ADIE (Assessment, Diagnosis, Interventions, and Evaluation). A collaborative care amid multidisciplinary diabetes team is needed for implementing along with evaluating the feasibility of the study findings. Moreover, active family participation also plays a crucial role to achieve successful management of diabetic foot ulcer at home.

A fibrinous and allogeneic fibroblast-enriched membrane as a biocompatible material can improve diabetic wound healing

The novel fibroblast-loaded fibrin membrane was prepared to promote diabetic wound healing.

Stem cell therapy for diabetic foot ulcers: a review of preclinical and clinical research

BACKGROUND

Diabetic foot ulcer (DFU) is a severe complication of diabetes, preceding most diabetes-related amputations. DFUs require over US$9 billion for yearly treatment and are now a global public health issue. DFU occurs in the setting of ischemia, infection, neuropathy, and metabolic disorders that result in poor wound healing and poor treatment options. Recently, stem cell therapy has emerged as a new interventional strategy to treat DFU and appears to be safe and effective in both preclinical and clinical trials. However, variability in the stem cell type and origin, route and protocol for administration, and concomitant use of angioplasty confound easy interpretation and generalization of the results.

METHODS

The PubMed, Google Scholar, and EMBASE databases were searched and 89 preclinical and clinical studies were selected for analysis.

RESULTS

There was divergence between preclinical and clinical studies regarding stem cell type, origin, and delivery techniques. There was heterogeneous preclinical and clinical study design and few randomized clinical trials. Granulocyte-colony stimulating factor was employed in some studies but with differing protocols. Concomitant performance of angioplasty with stem cell therapy showed increased efficiency compared to either therapy alone.

CONCLUSIONS

Stem cell therapy is an effective treatment for diabetic foot ulcers and is currently used as an alternative to amputation for some patients without other options for revascularization. Concordance between preclinical and clinical studies may help design future randomized clinical trials.

Assessing the Healing of Venous Leg Ulcers Using a Noncontact Near-Infrared Optical Imaging Approach

Objective: Venous leg ulcers (VLUs) are one of the most common complications in lower extremity wounds. To date, clinicians employ visual inspection of the wound site during its healing process by monitoring surface granulation and reduction in wound size across weeks of treatment. In this study, a handheld near-infrared optical scanner (NIROS) has been developed at the Optical Imaging Laboratory to differentiate healing from nonhealing VLUs based on differences in blood flow to the wound and its surroundings. Approach: Noncontact near-infrared (NIR) area imaging of 12 VLUs have been carried out at two podiatric clinics. Diffuse reflectance images of the wounds were used to quantify optical contrasts between the wound and its surroundings. The variability in imaging conditions, analysis, and operator dependency were assessed to determine the robustness of the imaging approach. Results: Optical contrast obtained from diffuse reflectance images of VLUs were distinctly different for healing (positive contrast) and nonhealing (negative contrast) wounds, independent of the varying imaging and data analysis conditions. Innovation: NIR imaging of wounds to differentiate healing from nonhealing VLUs using a noncontact wide-area imager has been demonstrated for the first time. Conclusion: The application of a portable handheld imager to assess the healing or nonhealing nature of VLUs during weekly clinical treatment is significant since physiological changes, as observed using NIROS, manifest before visual reduction in wound size during the healing process.

Adipose Tissue-Derived Stromal Cells for Wound Healing

Skin as the outer layer covers the body. Wounds can affect this vital organ negatively and disrupt its functions. Wound healing as a biological process is initiated immediately after an injury. This process consists of three stages: inflammation, proliferation, remodeling. Generally, these three stages occur continuously and timely. However, some factors such as infection, obesity and diabetes mellitus can interfere with these stages and impede the normal healing process which results in chronic wounds. Financial burden on both patients and health care systems, negative biologic effect on the patient's general health status and reduction in quality of life are a number of issues which make chronic wounds as a considerable challenge. During recent years, along with advances in the biomedical sciences, various surgical and non-surgical therapeutic methods have been suggested. All of these suggested treatments have their own advantages and disadvantages. Recently, cell-based therapies and regenerative medicine represent promising approaches to wound healing. Accordingly, several types of mesenchymal stem cells have been used in both preclinical and clinical settings for the treatment of wounds. Adipose-derived stromal cells are a cost-effective source of mesenchymal stem cells in wound management which can be easily harvest from adipose tissues through the less invasive processes with high yield rates. In addition, their ability to secrete multiple cytokines and growth factors, and differentiation into skin cells make them an ideal cell type to use in wound treatment. This is a concise overview on the application of adipose-derived stromal cells in wound healing and their role in the treatment of chronic wounds.

Efficacy and Time Sensitivity of Amniotic Membrane treatment in Patients with Diabetic Foot Ulcers: A Systematic Review and Meta-analysis

INTRODUCTION

Diabetic foot ulcers (DFUs) are complex chronic wounds which have a major long-term impact on the morbidity, mortality and quality of patients. The objective of this study was to assess the efficacy and time sensitivity of human amnion/chorion membrane treatment in patients with chronic DFUs.

METHODS

The Cochrane Library, PubMed, Embase and Web of Science databases were systematically searched to identify relevant articles up to 10 April 2017. All randomized controlled trials (RCTs) comparing human amnion/chorion membrane + standard therapy and standard therapy alone in patients with DFUs were included in the analysis. Eligible studies were reviewed and data extracted into standard form. The Cochrane Collaboration's tool for assessing the risk of bias was used. Review manager version 5.3 software was used for statistical analysis. Data were analyzed using a random effect model.

RESULTS

Overall, the initial search of the four databases identified 352 published studies; of these, seven RCTS were ultimately included in the meta-analysis. The overall test effect in the group assessed at 4 weeks was Z = 4.14 [P < 0.0001; odds ratio (OR) 0.05; 95% confidence interval (CI) 0.01-0.21]. The overall test effect in the group assessed at 6 weeks was Z = 4.28 (P < 0.0001; OR 0.07; 95% CI 0.02-0.23). The overall effect in the group assessed at 12 weeks was Z = 4.96 (P < 0.00001; OR 0.10; 95% CI 0.04-0.24. The results showed that patients receiving amniotic membrane + standard therapy had far fewer incomplete healing wounds than those receiving standard of care alone. Assessment of the wound healing state at 4 and 6 weeks revealed that the wound healing state was almost the same, but there was a net difference of wound healing state at 12 weeks.

CONCLUSION

Human amnion/chorion membrane + standard of care treatment heals DFUs significantly faster than standard of care alone. When using the amnion in patients with DFUs, the optimal times to assess progress in wound healing should be 4 and 12 weeks.

Treatment of diabetic foot ulcers with Therapeutic Magnetic Resonance (TMR®) improves the quality of granulation tissue

Diabetic foot ulcers (DFUs) often result in severely adverse outcomes, such as serious infections, hospitalization, and lower extremity amputations. In last few years, to improve the outcome of DFUs, clinicians and researchers put their attention on the application of low intensity pulsating electro-magnetic fields through Therapeutic Magnetic Resonance (TMR®). In our study, patients with DFUs have been divided into two groups: The Sham Group treated with non-functioning TMR® device, and the Active Group treated with a functioning device. Biopsies were recovered from ulcers before and after a 15-day treatment with both kind of TMR® device. To recognize signs of inflammation or healing process, the harvested biopsies were subjected to histological and molecular analyses. The histological analysis showed a change in cell population after treatment with TMR®: an increase of fibroblasts and endothelial cells with a reduction of inflammatory cells. After TMR® application, the gene expression profile analysis revealed an improvement in extracellular matrix components such as matrix metalloproteinases, collagens and integrins, a reduction in pro-inflammatory interleukins, and an increase in growth factors expression. In conclusion, our research has identified histological and molecular features of reduced inflammation and increased cell proliferation during the wound healing process in response to TMR® application.

Topical aqueous extract of Ephedra alata can improve wound healing in an animal model

PURPOSE

Ephedra alata (E. alata) is perennial tough shrub plant that grows in Palestine and other regions. It is used often in folk's medicine for the treatment of various diseases. In this project, E. alata extract was tested for its ability to improve wound and burn healing.

METHODS

An aqueous extract of E. alata was prepared and underwent several phytochemical analyses for the presence of the major classes of phytochemical compounds. After that, a polyethylene glycol-based ointment containing the extract of E. alata was prepared and its wound and burn healing activities were tested in-vivo using an animal model for deep wound and full thickness skin burn. The effect was compared against a placebo ointment. Skin biopsies were evaluated by a blinded clinical histopathologist, in addition to digital analysis.

RESULTS

Phytochemical analysis demonstrated the presence of the major classes of phytochemical compounds in the prepared extract including flavonoids, alkaloids, phytosteroids, phenolic compounds, volatile oils and tannins. As compared to placebo ointment, E. alata ointment significantly improved the healing of the wound ulcers, whereas it showed no advantage on the quality of the healing of burn ulcers.

CONCLUSION

E. alata extract is rich in phytochemical compounds and can improve wound healing when applied topically.

Effect of low-level light therapy on diabetic foot ulcers: a near-infrared spectroscopy study

Diabetic foot ulcer (DFU) is a diabetic complication due to peripheral vasculopathy and neuropathy. A promising technology for wound healing in DFU is low-level light therapy (LLLT). Despite several studies showing positive effects of LLLT on DFU, LLLT’s physiological effects have not yet been studied. The objective of this study was to investigate vascular and nervous systems modification in DFU after LLLT. Two samples of 45 DFU patients and 11 healthy controls (HCs) were recruited. The total hemoglobin (totHb) concentration change was monitored before and after LLLT by near-infrared spectroscopy and analyzed in time and frequency domains. The spectral power of the totHb changes in the very-low frequency (VLF, 20 to 60 mHz) and low frequency (LF, 60 to 140 mHz) bandwidths was calculated. Data analysis revealed a mean increase of totHb concentration after LLLT in DFU patients, but not in HC. VLF/LF ratio decreased significantly after the LLLT period in DFU patients (indicating an increased activity of the autonomic nervous system), but not in HC. Eventually, different treatment intensities in LLLT therapy showed a different response in DFU. Overall, our results demonstrate that LLLT improves blood flow and autonomic nervous system regulation in DFU and the importance of light intensity in therapeutic protocols.

Stem Cell-Containing Hyaluronic Acid-Based Spongy Hydrogels for Integrated Diabetic Wound Healing

The detailed pathophysiology of diabetic foot ulcers is yet to be established and improved treatments are still required. We propose a strategy that directs inflammation, neovascularization, and neoinnervation of diabetic wounds. Aiming to potentiate a relevant secretome for nerve regeneration, stem cells were precultured in hyaluronic acid-based spongy hydrogels under neurogenic/standard media before transplantation into diabetic mice full-thickness wounds. Acellular spongy hydrogels and empty wounds were used as controls. Re-epithelialization was attained 4 weeks after transplantation independently of the test groups, whereas a thicker and more differentiated epidermis was observed for the cellular spongy hydrogels. A switch from the inflammatory to the proliferative phase of wound healing was revealed for all the experimental groups 2 weeks after injury, but a significantly higher M2(CD163⁺)/M1(CD86⁺) subtype ratio was observed in the neurogenic preconditioned group that also failed to promote neoinnervation. A higher number of intraepidermal nerve fibers were observed for the unconditioned group probably due to a more controlled transition from the inflammatory to the proliferative phase. Overall, stem cell-containing spongy hydrogels represent a promising approach to enhance diabetic wound healing by positively impacting re-epithelialization and by modulating the inflammatory response to promote a successful neoinnervation.

Patients' intention to speak up for health care providers' hand hygiene in inpatient diabetic foot wound treatment: a cross-sectional survey in diabetes outpatient centres in Lower Saxony, Germany

Hand hygiene in wound care by health care providers (HCPs) is a key principle in treating hospitalized patients with diabetic foot infections. This study aimed to estimate the extent to which patients with type-2-diabetes (T2D) intend to speak up for HCPs' hand hygiene during inpatient foot treatment, test whether this motivation increases given the hospital would invite patients to speak up, and identify associations with socio-demographics, knowledge of hand hygiene requirements, and diabetes-related factors. A questionnaire-survey was conducted in eight diabetes outpatient centres in Lower Saxony/Germany. Intentions to speak up (without and with institutional encouragement) and knowledge about hand hygiene during foot-care were assessed. Analyses of variance were conducted, partly as repeated measures-models with intention-items as within-subject factor. N = 473 patients participated (response = 77.4%). N = 177 (41%) strongly intended to speak up. Institutional encouragement was associated with an increased rate of strong (54% vs. 41%; p < .001) and higher mean intention (M = 3.9 vs. 3.4 with vs. without encouragement [5-point-scales]; F(1, 434) = 41.5, p < .001). In patients without diabetic foot syndrome, this effect was limited to those with at least medium school education (F(2, 292) = 4.4, p = .013) and knowledge on HCPs' hand hygiene (F(2, 294) = 3.1, p = .047). In conclusion, a majority of T2D-patients in diabetes outpatient centres intend to speak for HCPs' hand hygiene in inpatient foot treatment, and are receptive to institutional encouragement. However, this presupposes at least medium education and knowledge about hand hygiene, emphasizing that patient empowerment begins with knowledge.

Evaluation of wound healing in diabetic foot ulcer using platelet-rich plasma gel: A single-arm clinical trial

The aim of the present study was to evaluate the effectiveness of using autologous platelet-rich plasma (PRP) gel for treatment of diabetic foot ulcer (DFU) during the first 4 weeks of the treatment. In this longitudinal and single-arm trial, 100 patients were randomly selected after meeting certain inclusion and exclusion criteria; of these 100 patients, 70 (70%) were enrolled in the trial. After the primary care actions such as wound debridement, the area of each wound was calculated and recorded. The PRP therapy (2mL/cm² of ulcers) was performed weekly until the healing time for each patient. We used one sample T-test for healing wounds and Bootstrap resampling approach for reporting confidence interval with 1000 Bootstrap samples. The p-value<0.05 were considered statistically significant. The mean (SD) of DFU duration was 19.71 weeks (4.94) for units sampling. The ratio of subjects who withdrew from the study was calculated to be 2 (2.8%). Average area of 71 ulcers in the mentioned number of cases was calculated to be 6.11cm² (SD: 4.37). Also, the mean, median (SD) of healing time was 8.7, 8 weeks (SD: 3.93) except for 2 mentioned cases. According to one sample T-test, wound area (cm²), on average, significantly decreased to 51.9% (CI: 46.7-57.1) through the first four weeks of therapy. Furthermore, significant correlation (0.22) was not found between area of ulcers and healing duration (p-value>0.5). According to the results, PRP could be considered as a candidate treatment for non-healing DFUs as it may prevent future complications such as amputation or death in this pathological phenomenon.

Remote ischaemic conditioning in the context of type 2 diabetes and neuropathy: the case for repeat application as a novel therapy for lower extremity ulceration

An emerging treatment modality for reducing damage caused by ischaemia–reperfusion injury is ischaemic conditioning. This technique induces short periods of ischaemia that have been found to protect against a more significant ischaemic insult. Remote ischaemic conditioning (RIC) can be administered more conveniently and safely, by inflation of a pneumatic blood pressure cuff to a suprasystolic pressure on a limb. Protection is then transferred to a remote organ via humoral and neural pathways. The diabetic state is particularly vulnerable to ischaemia–reperfusion injury, and ischaemia is a significant cause of many diabetic complications, including the diabetic foot. Despite this, studies utilising ischaemic conditioning and RIC in type 2 diabetes have often been disappointing. A newer strategy, repeat RIC, involves the repeated application of short periods of limb ischaemia over days or weeks. It has been demonstrated that this improves endothelial function, skin microcirculation, and modulates the systemic inflammatory response. Repeat RIC was recently shown to be beneficial for healing in lower extremity diabetic ulcers. This article summarises the mechanisms of RIC, and the impact that type 2 diabetes may have upon these, with the role of neural mechanisms in the context of diabetic neuropathy a focus. Repeat RIC may show more promise than RIC in type 2 diabetes, and its potential mechanisms and applications will also be explored. Considering the high costs, rates of chronicity and serious complications resulting from diabetic lower extremity ulceration, repeat RIC has the potential to be an effective novel advanced therapy for this condition.

Neuropathy and Diabetic Foot Syndrome

Diabetic foot ulceration is a serious complication of diabetes mellitus worldwide and the most common cause of hospitalization in diabetic patients. The etiology of diabetic foot ulcerations is complex due to their multifactorial nature; in the pathophysiology of diabetic foot ulceration polyneuropathy is important. Proper adherence to standard treatment strategies and interdisciplinary cooperation can reduce the still high rates of major amputations.

Delivery of mesenchymal stem cells in biomimetic engineered scaffolds promotes healing of diabetic ulcers

AIM

We hypothesized that delivery of mesenchymal stem cells (MSCs) in a biomimetic collagen scaffold improves wound healing in a diabetic mouse model.

MATERIALS & METHODS

Rolled collagen scaffolds containing MSCs were implanted or applied topically to diabetic C57BL/6 mice with excisional wounds.

RESULTS

Rolled scaffolds were hypoxic, inducing MSC synthesis and secretion of VEGF. Diabetic mice with wounds treated with rolled scaffolds containing MSCs showed increased healing compared with controls. Histologic examination showed increased cellular proliferation, increased VEGF expression and capillary density, and increased numbers of macrophages, fibroblasts and smooth muscle cells. Addition of laminin to the collagen scaffold enhanced these effects.

CONCLUSION

Activated MSCs delivered in a biomimetic-collagen scaffold enhanced wound healing in a translationally relevant diabetic mouse model.

Hepatocyte Growth Factor Effects on Mesenchymal Stem Cells Derived from Human Arteries: A Novel Strategy to Accelerate Vascular Ulcer Wound Healing

Vascular ulcers are a serious complication of peripheral vascular disease, especially in diabetics. Several approaches to treat the wounds are proposed but they show poor outcomes and require long healing times. Hepatocyte Growth Factor/Scatter Factor (HGF/SF) is a pleiotropic cytokine exerting many biological activities through the c-Met receptor. This study was aimed at verifying whether HGF/SF influences proliferation, migration, and angiogenesis on mesenchymal stem cells isolated from human arteries (hVW-MSCs). hVW-MSCs were exposed to NIBSC HGF/SF (2.5, 5, 10, and 70 ng/mL) from 6 hrs to 7 days. HGF and c-MET mRNA and protein expression, cell proliferation (Alamar Blue and Ki-67 assay), migration (scratch and transwell assays), and angiogenesis (Matrigel) were investigated. hVW-MSCs displayed stemness features and expressed HGF and c-MET. HGF/SF did not increase hVW-MSC proliferation, whereas it enhanced the cell migration, the formation of capillary-like structures, and the expression of angiogenic markers (vWF, CD31, and KDR). The HGF/SF effects on hVW-MSC migration and angiogenic potential are of great interest to accelerate wound healing process. Local delivery of HGF/SF could therefore improve the healing of unresponsive vascular ulcers.

Challenges in the Treatment of Chronic Wounds

Significance: Chronic wounds include, but are not limited, to diabetic foot ulcers, venous leg ulcers, and pressure ulcers. They are a challenge to wound care professionals and consume a great deal of healthcare resources around the globe. This review discusses the pathophysiology of complex chronic wounds and the means and modalities currently available to achieve healing in such patients. Recent Advances: Although often difficult to treat, an understanding of the underlying pathophysiology and specific attention toward managing these perturbations can often lead to successful healing. Critical Issues: Overcoming the factors that contribute to delayed healing are key components of a comprehensive approach to wound care and present the primary challenges to the treatment of chronic wounds. When wounds fail to achieve sufficient healing after 4 weeks of standard care, reassessment of underlying pathology and consideration of the need for advanced therapeutic agents should be undertaken. However, selection of an appropriate therapy is often not evidence based. Future Directions: Basic tenets of care need to be routinely followed, and a systematic evaluation of patients and their wounds will also facilitate appropriate care. Underlying pathologies, which result in the failure of these wounds to heal, differ among various types of chronic wounds. A better understanding of the differences between various types of chronic wounds at the molecular and cellular levels should improve our treatment approaches, leading to better healing rates, and facilitate the development of new more effective therapies. More evidence for the efficacy of current and future advanced wound therapies is required for their appropriate use.

Nanomaterials for wound healing: scope and advancement

Innovative methods for treating impaired and hard-to-heal wounds are needed. Novel strategies are needed for faster healing by reducing infection, moisturizing the wound, stimulating the healing mechanisms, speeding up the wound closure and reducing scar formation. In the past few years, nanotechnology has been constantly revolutionizing the treatment and management of wound care, by offering novel solutions which include but are not limited to: state-of-the-art materials, so called 'smart' biomaterials and theranostic nanoparticles. Nanotechnology-based therapy has recently announced itself as a possible next-generation therapy that is able to advance wound healing to cure chronic wounds. In this communication, the recent progress in advanced therapy for cutaneous wound healing during last 5 years using a nanotechnology-based approach is summarized.

Emerging drugs for the treatment of wound healing

INTRODUCTION

Wound healing can be characterized as underhealing, as in the setting of chronic wounds, or overhealing, occurring with hypertrophic scar formation after burn injury. Topical therapies targeting specific biochemical and molecular pathways represent a promising avenue for improving and, in some cases normalizing, the healing process.

AREAS COVERED

A brief overview of both normal and pathological wound healing has been provided, along with a review of the current clinical guidelines and treatment modalities for chronic wounds, burn wounds and scar formation. Next, the major avenues for wound healing drugs, along with drugs currently in development, are discussed. Finally, potential challenges to further drug development, and future research directions are discussed.

EXPERT OPINION

The large body of research concerning wound healing pathophysiology has provided multiple targets for topical therapies. Growth factor therapies with the ability to be targeted for localized release in the wound microenvironment are most promising, particularly when they modulate processes in the proliferative phase of wound healing.