Functional hydrogel dressings offer a promising therapeutic approach, and optimizing their formulations is crucial for improving diabetic foot ulcers (DFUs) outcomes. This study explores the comparative efficacy of different functional hydrogel dressings in DFUs treatment.

We conducted a systematic review and Bayesian network meta-analysis of randomized controlled trials evaluating functional hydrogel dressings for DFUs treatment. A comprehensive search was performed across PubMed, Embase, CENTRAL, CNKI and Web of Science from inception to June 2024. Bayesian network meta-analysis was employed to synthesize and compare the relative efficacy of hydrogel interventions, defined as the number of patients with complete wound closure.

In total, 23 studies involving 1671 patients with DFUs were included. The analysis revealed that immuno-regulating hydrogels (IRHs) had the highest effect estimate (2.2, 95% CI: 1.6, 3.2), compared with anti-bacterial hydrogels (ABHs) ranked last (1.3, 95% CI: 0.78, 2.3). Multi-functional hydrogels (MFHs) and proliferation-promoting hydrogels (PPHs) displayed intermediate effects (1.7, 95% CI: 1.2, 2.4). The relative efficacy ranking was IRH > MFH/PPH > ABH > placebo. The risk of adverse events was lower in functional hydrogel groups relative to placebo (0.75, 95% CI: 0.56, 0.96). Node-splitting analysis confirmed the consistency between direct and indirect evidence for IRH versus ABH. A funnel plot analysis indicated no significant publication bias, affirming the robustness of our findings.

This study provides a comprehensive evaluation of functional hydrogel dressings for DFUs treatment, highlighting the potential of IRH as the most effective option. These insights will guide future research and clinical applications to improve DFUs management.

Diabetic foot ulcers (DFUs) are a devastating complication of diabetes mellitus (DM) that affect millions of people worldwide every year. They have a long-term impact on patients' quality of life and pose a significant challenge for both patients and clinicians, alongside negative economic implications on affected individuals. The current therapeutic approaches are costly and, in many cases, ineffective, highlighting the urgent need to develop novel, affordable, more efficient, and personalized treatments. Recent advances in high-throughput omics technologies, including proteomics, bulk RNA sequencing (bulk RNA-seq), single-cell RNA sequencing (scRNA-seq), and spatial transcriptomics in both preclinical animal and human clinical studies, have enhanced our understanding of the molecular function and mechanisms of DFUs, thereby offering potential for targeted therapies. Additionally, these technologies provide valuable insights behind the mechanism of action of novel wound dressings and treatments. In this review, we outline the latest application of omics technologies in DFU preclinical animal and human clinical research on diabetic wound healing, and spotlight recent findings.A graphical abstract is available with this article.

Electrical stimulation (ES) therapy has emerged as a promising method for improving wound healing by mimicking the body's natural electric fields. However, traditional ES devices often fall short in practical applications due to their bulkiness and inefficiency. Current tools for electrical stimulation are hindered by issues such as poor sustainability, limited flexibility, and inadequate biocompatibility. To address these challenges, we have developed a novel self-powered electrical stimulation fabric dressing (SESFD). This innovative dressing employs advanced electrochemical deposition technology to integrate fiber electrodes seamlessly into the fabric using standard textile manufacturing methods. Additionally, we incorporated a gel electrolyte infused with antimicrobial agents to enhance protection against bacterial infections during electrical stimulation. To evaluate the effectiveness of the SESFD in promoting healing for chronic diabetic wounds, we conducted rigorous in vivo studies. The results demonstrated that the SESFD significantly improved cell proliferation and migration within the wound tissue while effectively reducing bacterial growth. These enhancements contributed to faster wound closure, decreased inflammatory response, increased collagen deposition, and improved angiogenesis. Furthermore, the SESFD displayed excellent mechanical properties, extended discharge durability, and stable voltage output even under mechanical deformation. These attributes greatly enhance user experience and comfort for patients throughout the healing process. This study positions the SESFD as a groundbreaking solution that combines electrical stimulation with antimicrobial treatment for diabetic wound care. It represents a sustainable, flexible, and biocompatible approach to accelerating wound healing and improving treatment outcomes.

Chronic wounds, defined by their prolonged healing process, significantly impair patients' quality of life and impose a hefty financial burden on healthcare systems worldwide. Sex- and gender-specific mechanisms regulate inflammation and infection, angiogenesis, matrix synthesis and cell recruitment. All of these processes contribute to cutaneous wound healing but remain largely understudied. This review aims to spotlight the innovative realm of bioengineering and nanomedicine, which is at the helm of revolutionizing complex chronic wound care. It underscores the significance of integrating patient sex into the development and (pre)clinical testing of these avant-garde treatment modalities, in order to enhance healing prospects for all patients regardless of sex. Moreover, we explore the representation of male and female patients in clinical trials of bioengineered and nanomedicine products. Finally, we examine the primary reasons for the historical neglect in translating sex-specific wound healing research into clinical practice and propose strategic solutions. By tackling these issues, the article advocates advanced treatment frameworks that could significantly improve healing outcomes for individuals of all sexes, thereby optimizing both efficacy and inclusivity in chronic wound management.

To provide an overview of the use of autogenous platelet concentrates (APCs) in periodontal regeneration and to conduct a systematic review (SR) of the treatment outcomes of periodontal intrabony defects by using platelet-rich fibrin (PRF) compared with other commonly utilized modalities. The eligibility criteria comprised randomized controlled trials (RCTs) comparing the clinical outcomes of PRF with that of other modalities. Studies were classified into 21 categories and into five different groups as follows: Group I (1) open flap debridement (OFD) alone versus OFD/PRF, (2) OFD versus Titanium-PRF (T-PRF) Group II, (3) Comparative PRF protocols (PRF vs. T-PRF), Group III (Comparative Studies to PRF): (4) OFD/PRP versus OFD/PRF, (5) OFD/bone graft(BG)/PRGF versus OFD/BG/PRF, (6) OFD/EMD versus OFD/PRF, (7) OFD/BG/EMD versus OFD/BG/PRF, (8) OFD/collagen membrane (CM) versus OFD/PRF, (9) OFD/BG/BM versus OFD/BG/PRF, (10) OFD/BG versus OFD/PRF, Group IV (Addition of PRF to treatment groups) (11) OFD/BG versus OFD/BG/PRF, (12) OFD/GTR versus OFD/GTR + PRF (13) OFD/EMD versus OFD/EMD/PRF (14) OFD/BG/BM versus OFD/BG/BM/PRF, Group V (Addition of Biomaterial/Biomolecule to PRF): OFD/PRF versus … (15) OFD/PRF/BG, (16) OFD/PRF/antibiotic, (17) OFD/PRF/Metformin, (18) OFD/PRF/Bisphosphonates, (19) OFD/PRF/Statins, (20) OFD/BG/PRF versus OFD/BG/PRF/Statins, and (21) OFD/PRF/low-level laser therapy (LLLT). Weighted means and forest plots were calculated for probing pocket depth (PPD), clinical attachment level (CAL), and radiographic bone fill (RBF). From 596 records identified, 55 RCTs were included. Group I: The use of OFD/PRF statistically significantly reduced PPD and improved CAL and RBF when compared to OFD. Group II: A significant difference between various PRF protocols was only observed for PPD. Group III: No significant advantage was found when comparing OFD/PRF to the following groups: OFD/PRP, OFD/EMD, OFD/BM, or OFD/BG. Group IV: The addition of PRF to OFD/BG led to significant improvements in PPD, CAL and RBF compared with OFD/BG alone. Group V: The addition of either a BG as well as three of the following biomolecules (metformin, bisphosphonates, and statins) to OFD/PRF led to statistically significant improvements in PPD, CAL, and/or RBF when compared to OFD/PRF alone. The use of PRF significantly improved clinical outcomes in intrabony defects when compared to OFD alone. Similar results were observed when OFD/PRF was compared with OFD/BG, OFD/EMD, OFD/PRP, and OFD/BM. The addition of PRF to a bone grafting material as well as the addition of various small biomolecules to PRF may offer additional clinical advantages, thus warranting further investigations. Future research investigating various protocols of PRF, longer-term outcomes, as well as PRF at the human histological level remains needed.

Autologous or allogeneic platelet-derived extracellular vesicles (pEVs) show potential in enhancing tissue recovery and healing chronic wounds. pEVs promote neovascularization and cell migration while reducing inflammation, oxidative stress, and scarring. However, their efficacy in clinical settings is challenged by their susceptibility to washout by wound exudate. Hydrogel-based bandages are effective carriers that stabilize pEVs for optimal personalized wound care. These bandages can be tailored for easy removal to minimize damage to regenerated tissue and can incorporate antibacterial or moisture-retaining properties. Furthermore, the possibility of integrating sensors in the wound bed will enable a theragnostic approach to healing. This review explores advancements in pEV-loaded hydrogels and their potential for personalized clinical applications.

Bioactive peptides and proteins (BAPPs) are promising therapeutic agents for tissue repair with considerable advantages, including multifunctionality, specificity, biocompatibility, and biodegradability. However, the high complexity of tissue microenvironments and their inherent deficiencies such as short half-live and susceptibility to enzymatic degradation, adversely affect their therapeutic efficacy and clinical applications. Investigating the fundamental mechanisms by which BAPPs modulate the microenvironment and developing rational delivery strategies are essential for optimizing their administration in distinct tissue repairs and facilitating clinical translation. This review initially focuses on the mechanisms through which BAPPs influence the microenvironment for tissue repair via reactive oxygen species, blood and lymphatic vessels, immune cells, and repair cells. Then, a variety of delivery platforms, including scaffolds and hydrogels, electrospun fibers, surface coatings, assisted particles, nanotubes, two-dimensional nanomaterials, and nanoparticles engineered cells, are summarized to incorporate BAPPs for effective tissue repair, modification strategies aimed at enhancing loading efficiencies and release kinetics are also reviewed. Additionally, the delivery of BAPPs can be precisely regulated by endogenous stimuli (glucose, reactive oxygen species, enzymes, pH) or exogenous stimuli (ultrasound, heat, light, magnetic field, and electric field) to achieve on-demand release tailored for specific tissue repair needs. Furthermore, this review focuses on the clinical potential of BAPPs in facilitating tissue repair across various types, including bone, cartilage, intervertebral discs, muscle, tendons, periodontal tissues, skin, myocardium, nervous system (encompassing brain, spinal cord, and peripheral nerve), endometrium, as well as ear and ocular tissue. Finally, current challenges and prospects are discussed.

Objectives: To identify proteins that are prognostic for diabetic foot ulcer (DFU) healing and may serve as biomarkers for its management, serum samples were analyzed from diabetic mellitus (DM) patients. Approach: The serum specimens that were evaluated in this study were obtained from DM patients with DFU who participated in a prospective study and were seen biweekly until they healed their ulcer or the exit visit at 12 weeks. The group was divided into Healers (who healed their DFU during the study) and Non-Healers. Results: Interleukin (IL)-10, IL-4, IL-5, IL-6, and IL-13 and interferon-gamma were higher in the Healers while Fractalkine, IL-8, and TNFα were higher in the Non-Healers. The trajectory of IL-10 levels remained stable over time within and across groups, resulting in a strong prognostic ability for the prospective DFU healing course. Classification and Regression Tree analysis created an 11-node decision tree with healing status as the categorical response. Innovation: Consecutive measurements of proteins associated with wound healing can identify biomarkers that can predict DFU healing over a 12-week period. IL-10 was the strongest candidate for prediction. Conclusion: Measurement of serum proteins can serve as a successful strategy in guiding clinical management of DFU. The data also indicate likely superior performance of building a multiprotein biomarker score instead of relying on single biomarkers.

Significance: Chronic diabetic wounds on the lower extremities (diabetic foot ulcers, DFU) are one of the most prevalent and life-threatening complications of diabetes, responsible for significant loss of quality of life and cost to the health care system. Available pharmacologic treatments fail to achieve complete healing in many patients. Recent studies and investigational treatments have highlighted the potential of modulating wound pH in DFU. Recent Advances: Data from in vitro, preclinical, and clinical studies highlight the role of pH in the pathophysiology of DFU, and topical administration of pH-lowering agents have shown promise as a therapeutic strategy for diabetic wounds. In this critical review, we describe the role of pH in DFU pathophysiology and present selected low-molecular-weight and hydrogel-based pH-modulating systems for wound healing and infection control in diabetic wounds. Critical Issues: The molecular mechanisms leading to pH alterations in diabetic wounds are complex and may differ between in vitro models, animal models of diabetes, and the human pathophysiology. Wound pH-lowering bandages for DFU therapy must be tested in established animal models of diabetic wound healing and patients with diabetes to establish a comprehensive benefit-risk profile. Future Directions: As our understanding of the role of pH in the pathophysiology of diabetic wounds is deepening, new treatments for this therapeutic target are being developed and will be tested in preclinical and clinical studies. These therapeutic systems will establish a target product profile for pH-lowering treatments such as an optimal pH profile for each wound healing stage. Thus, controlling wound bed pH could become a powerful tool to accelerate chronic diabetic wound healing.

Chronic wounds affect ~2% of the U.S. population and increase risks of amputation and mortality. Unfortunately, treatments for such wounds are often expensive, complex, and only moderately effective. Electrotherapy represents a cost-effective treatment; however, its reliance on bulky equipment limits its clinical use. Here, we introduce water-powered, electronics-free dressings (WPEDs) that offer a unique solution to this issue. The WPED performs even under harsh conditions-situations wherein many present treatments fail. It uses a flexible, biocompatible magnesium-silver/silver chloride battery and a pair of stimulation electrodes; upon the addition of water, the battery creates a radial electric field. Experiments in diabetic mice confirm the WPED's ability to accelerate wound closure and promote healing by increasing epidermal thickness, modulating inflammation, and promoting angiogenesis. Across preclinical wound models, the WPED-treated group heals faster than the control with wound closure rates comparable to treatments requiring expensive biologics and/or complex electronics. The results demonstrate the WPED's potential as an effective and more practical wound treatment dressing.

Since the 1800s, platelet-rich plasma (PRP) has been used as a treatment for a wide range of medical conditions with a concomitant effect of tending to reduce the need for some invasive procedures. The aim of this narrative review was to concisely document the history and current usage of PRP specifically in the field of dermatology. Four databases (PubMed, Google Scholar, CINAHL, and Web of Science) were searched for primary articles written in English that evaluated human subjects and focused on PRP use in dermatology. Initial search terms included "platelet rich plasma," "alopecia," "androgenic alopecia," "dermatology," "PDGF," "aging," "skin rejuvenation," "diabetic ulcers," "venous leg ulcers," "acne," "acne scars," "scars," "hyperpigmentation," "melasma," "hypopigmentation," "vitiligo," and "PRP." After review, articles were excluded if they were commentaries, editorials, animal studies, review articles, or were unrelated to dermatology. The bibliography of retrieved articles was also searched for relevant articles. The present review results describe the function of PRP from its first usage for thrombocytopenia to its usage for melasma. In this time frame, its use in dermatology has gone through many evolutions from using its healing factors for treating wounds to using it as the treatment for wrinkles, hair loss, scars, ulcers, and skin pigmentation disorders. Its anti-inflammatory and growth factors have been shown to initiate a healing cascade that promotes the growth and regeneration of tissues. It is hoped that this review will help educate patients and physicians about the efficacy of PRP therapy and thereby help avoid unnecessary invasive procedures for certain conditions.

Diabetes mellitus is associated with morbid complications such as diabetic foot ulcers (DFUs) that may lead to amputations or mortality if not managed adequately.

New adjunctive interventions to treat diabetic wounds include topical biologics and growth factors. This study aims to evaluate their efficacy in improving wound-healing outcomes and safety.

Comprehensive database searches of MEDLINE via PubMed, EMBASE, and Cochrane were performed from inception to December 2022. Three independent researchers selected the studies. Randomized controlled trials that compared the use of a topical biologic growth factor-containing regimen to other biologics or standard of care (SOC) were included. This review followed PRISMA guidelines. Risk of bias analysis was performed using the Jadad scale. Network meta-analysis was performed. Treatments were grouped into common nodes based on the type of biologic agent. Primary outcomes of interest were healing rate and time to wound closure. Secondary outcomes included wound infection, serious adverse events (AEs), and amputation rate.

Human umbilical cord (HUC) was associated with the highest cure, followed by recombinant human epidermal growth factor (hEGF). A significantly greater reduction in the time to cure DFUs was seen in HUC, hEGF, and fibroblast growth factor (FGF). There was a significantly lower risk of AEs when platelet-rich plasma (PRP) was administered.

HUC, hEGF, and FGF are promising topical biologics with statistically significant primary outcomes compared to SOC, while PRP is effective in reducing ulcer-related AEs. HUC has been found to be the most effective in terms of cure rate and a reduction in time to cure.

To evaluate the healing outcome of a platelet-rich plasma (PRP) gel prepared using TKKT01 (a wound care device to prepare the PRP gel) in patients with hard-to-heal diabetic foot ulcers (DFUs) and who showed an inadequate response to ≥4 weeks of standard of care (SoC).

This open-label, single-arm, multicentre study was conducted in 15 centres in Japan. Eligible patients received PRP gel treatment twice a week for eight weeks, followed by a final evaluation after the completion of week 8 (day 57). The primary endpoint was the percentage of patients who achieved ≥50% reduction in wound radius at the final evaluation (achievement criterion, ≥60% of patients). Secondary endpoints included: wound area and volume reduction rates; time to possible wound closure by secondary intention; time to possible wound closure using a relatively simple procedure (e.g., skin graft and suture); and safety at the final evaluation.

A total of 54 patients were included in the full analysis set, with 47 patients included in the per protocol set; the primary endpoint was met in 38/47 (80.9%) (95% confidence interval: 66.7-90.9%) patients who achieved ≥50% wound radius reduction at the final evaluation. High rates of wound area (72.8%) and volume (92.7%) reduction were observed at the final evaluation. The median time to possible wound closure by secondary intention and by use of a relatively simple procedure was 57 and 43 days, respectively. Complete wound closure at the final evaluation was achieved in 27 (57.4%) patients. No safety concerns were raised.

In this study, the efficacy and safety of PRP gel treatment with TKKT01 in patients with hard-to-heal DFUs in Japan were confirmed by our findings.

This study was funded by Rohto Pharmaceutical Co., Ltd., Japan. NO has been paid a consulting fee by Rohto Pharmaceutical Co., Ltd. KH is the Chief Medical Officer of Rohto Pharmaceutical. Co., Ltd. The other authors have no conflict of interest to declare.

Chronic wounds have emerged as an increasingly critical clinical challenge over the past few decades, due to their increasing incidence and socioeconomic burdens. Platelet-derived growth factor (PDGF) plays a pivotal role in regulating processes such as fibroblast migration, proliferation, and vascular formation during the wound healing process. The delivery of PDGF offers great potential for expediting the healing of chronic wounds. However, the clinical effectiveness of PDGF in chronic wound healing is significantly hampered by its inability to maintain a stable concentration at the wound site over an extended period. In this study, a controlled PDGF delivery system based on nanocapsules is proposed. In this system, PDGF is encapsulated within a degradable polymer shell. The release rate of PDGF from these nanocapsules can be precisely adjusted by controlling the ratios of two crosslinkers with different degradation rates within the shells. As demonstrated in a diabetic wound model, improved therapeutic outcomes with PDGF nanocapsules (nPDGF) treatment are observed. This research introduces a novel PDGF delivery platform that holds promise for enhancing the effectiveness of chronic wound healing.

Diabetic foot ulcer (DFU) is one of the most costly and serious complications of diabetes. Treatment of DFU is usually challenging and new approaches are required to improve the therapeutic efficiencies. This review aims to update new and upcoming adjunctive therapies with noninvasive characterization for DFU, focusing on bioactive dressings, bioengineered tissues, mesenchymal stem cell (MSC) based therapy, platelet and cytokine-based therapy, topical oxygen therapy, and some repurposed drugs such as hypoglycemic agents, blood pressure medications, phenytoin, vitamins, and magnesium. Although the mentioned therapies may contribute to the improvement of DFU to a certain extent, most of the evidence come from clinical trials with small sample size and inconsistent selections of DFU patients. Further studies with high design quality and adequate sample sizes are necessitated. In addition, no single approach would completely correct the complex pathogenesis of DFU. Reasonable selection and combination of these techniques should be considered.

Despite several promising preclinical studies performed over the past two decades, there remains a paucity of market-approved drugs to treat chronic lower extremity wounds in humans. This translational gap challenges our understanding of human chronic lower extremity wounds and the design of wound treatments. Current targeted drug treatments and delivery systems for lower extremity wounds rely heavily on preclinical animal models meant to mimic human chronic wounds. However, there are several key differences between animal preclinical wound models and the human chronic wound microenvironment, which can impact the design of targeted drug treatments and delivery systems. To explore these differences, this review delves into recent new drug technologies and delivery systems designed to address the chronic wound microenvironment. It also highlights preclinical models used to test drug treatments specific for the wound microenvironments of lower extremity diabetic, venous, ischemic, and burn wounds. We further discuss key differences between preclinical wound models and human chronic wounds that may impact successful translational drug treatment design.

Diabetic wound healing is uniquely challenging to manage due to chronic inflammation and heightened microbial growth from elevated interstitial glucose. Carbon monoxide (CO), widely acknowledged as a toxic gas, is also known to provide unique therapeutic immune modulating effects. To facilitate delivery of CO, we have designed hyaluronic acid-based CO-gas-entrapping materials (CO-GEMs) for topical and prolonged gas delivery to the wound bed. We demonstrate that CO-GEMs promote the healing response in murine diabetic wound models (full-thickness wounds and pressure ulcers) compared to N2-GEMs and untreated controls.

Management of severe diabetic foot ulcers (DFUs) remains challenging. Tibial cortex transverse transport (TTT) facilitates healing and limb salvage in patients with recalcitrant DFUs. However, the underlying mechanism is largely unknown, necessitating the establishment of an animal model and mechanism exploration.

Severe DFUs were induced in rats, then assigned to TTT, sham, or control groups (n=16/group). The TTT group underwent a tibial corticotomy, with 6 days each of medial and lateral transport; the sham group had a corticotomy without transport. Ulcer healing was assessed through Laser Doppler, CT angiography, histology, and immunohistochemistry. Serum HIF-1α, PDGF-BB, SDF-1, and VEGF levels were measured by ELISA.

The TTT group showed lower percentages of wound area, higher dermis thickness (all p < 0.001 expect for p = 0.001 for TTT vs Sham at day 6) and percentage of collagen content (all p < 0.001) than the other two groups. The TTT group had higher perfusion and vessel volume in the hindlimb (all p < 0.001). The number of CD31+ cells (all p < 0.001) and VEGFR2+ cells (at day 6, TTT vs Control, p = 0.001, TTT vs Sham, p = 0.006; at day 12, TTT vs Control, p = 0.003, TTT vs Sham, p = 0.01) were higher in the TTT group. The activity of HIF-1α, PDGF-BB, and SDF-1 was increased in the TTT group (all p < 0.001 except for SDF-1 at day 12, TTT vs Sham, p = 0.005). The TTT group had higher levels of HIF-1α, PDGF-BB, SDF-1, and VEGF in serum than the other groups (all p < 0.001).

TTT enhanced neovascularization and perfusion at the hindlimb and accelerated healing of the severe DFUs. The underlying mechanism is related to HIF-1α-induced angiogenesis.

Dermal wounds are a major global health burden made worse by common comorbidities such as diabetes and infection. Appropriate wound closure relies on a highly coordinated series of cellular events, ultimately bridging tissue gaps and regenerating normal physiological structures. Wound dressings are an important component of wound care management, providing a barrier against external insults while preserving the active reparative processes underway within the wound bed. The development of wound dressings with biomaterial constituents has become an attractive design strategy due to the varied functions intrinsic in biological polymers, such as cell instructiveness, growth factor binding, antimicrobial properties, and tissue integration. Using photosensitive agents to generate crosslinked or photopolymerized dressings in situ provides an opportunity to develop dressings rapidly within the wound bed, facilitating robust adhesion to the wound bed for greater barrier protection and adaptation to irregular wound shapes. Despite the popularity of this fabrication approach, relatively few experimental wound dressings have undergone preclinical translation into animal models, limiting the overall integrity of assessing their potential as effective wound dressings. Here, we provide an up-to-date narrative review of reported photoinitiator- and wavelength-guided design strategies for in situ light activation of biomaterial dressings that have been evaluated in preclinical wound healing models.

Chronic, non-healing wounds represent a significant challenge for healthcare systems worldwide, often requiring significant human and financial resources. Chronic wounds arise from the complex interplay of underlying comorbidities, such as diabetes or vascular diseases, lifestyle factors, and genetic risk profiles which may predispose extremities to local ischemia. Injuries are further exacerbated by bacterial colonization and the formation of biofilms. Infection, consequently, perpetuates a chronic inflammatory microenvironment, preventing the progression and completion of normal wound healing. The current standard of care (SOC) for chronic wounds involves surgical debridement along with localized wound irrigation, which requires inpatient care under general anesthesia. This could be followed by, if necessary, defect coverage via a reconstructive ladder utilizing wound debridement along with skin graft, local, or free flap techniques once the wound conditions are stabilized and adequate blood supply is restored. To promote physiological wound healing, a variety of approaches have been subjected to translational research. Beyond conventional wound healing drugs and devices that currently supplement treatments, cellular and immunotherapies have emerged as promising therapeutics that can behave as tailored therapies with cell- or molecule-specific wound healing properties. However, in contrast to the clinical omnipresence of chronic wound healing disorders, there remains a shortage of studies condensing the current body of evidence on cellular therapies and immunotherapies for chronic wounds. This review provides a comprehensive exploration of current therapies, experimental approaches, and translational studies, offering insights into their efficacy and limitations. Ultimately, we hope this line of research may serve as an evidence-based foundation to guide further experimental and translational approaches and optimize patient care long-term.

Slow-healing and chronic wounds represent a major global economic and medical burden, and there is significant unmet need for novel therapies which act to both accelerate wound closure and enhance biomechanical recovery of the skin. Here, we report a new approach in which bioactives that augment early stages of wound healing can kickstart and engender effective wound closure in healthy and diabetic, obese animals, and set the stage for subsequent tissue repair processes. We demonstrate that a nanomaterial dressing made of silk fibroin and gold nanorods (GNR) stimulates a pro-neutrophilic, innate immune, and controlled inflammatory wound transcriptomic response. Further, Silk-GNR, lasered into the wound bed, in combination with exogeneous histamine, accelerates early-stage processes in tissue repair leading to effective wound closure. Silk-GNR and histamine enhanced biomechanical recovery of skin, increased transient neoangiogenesis, myofibroblast activation, epithelial-to-mesenchymal transition (EMT) of keratinocytes and a pro-resolving neutrophilic immune response, which are hitherto unknown activities for these bioactives. Predictive and temporally coordinated delivery of growth factor nanoparticles that modulate later stages of tissue repair further accelerated wound closure in healthy and diabetic, obese animals. Our approach of kickstarting healing by delivering the "right bioactive at the right time" stimulates a multifactorial, pro-reparative response by augmenting endogenous healing and immunoregulatory mechanisms and highlights new targets to promote tissue repair.

It is critical that interventions used to enhance the healing of chronic foot ulcers in diabetes are backed by high-quality evidence and cost-effectiveness. In previous years, the systematic review accompanying guidelines published by the International Working Group of the Diabetic Foot performed 4-yearly updates of previous searches, including trials of prospective, cross-sectional and case-control design.

Due to a need to re-evaluate older studies against newer standards of reporting and assessment of risk of bias, we performed a whole new search from conception, but limiting studies to randomised control trials only.

For this systematic review, we searched PubMed, Scopus and Web of Science databases for published studies on randomised control trials of interventions to enhance healing of diabetes-related foot ulcers. We only included trials comparing interventions to standard of care. Two independent reviewers selected articles for inclusion and assessed relevant outcomes as well as methodological quality.

The literature search identified 22,250 articles, of which 262 were selected for full text review across 10 categories of interventions. Overall, the certainty of evidence for a majority of wound healing interventions was low or very low, with moderate evidence existing for two interventions (sucrose-octasulfate and leucocyte, platelet and fibrin patch) and low quality evidence for a further four (hyperbaric oxygen, topical oxygen, placental derived products and negative pressure wound therapy). The majority of interventions had insufficient evidence.

Overall, the evidence to support any other intervention to enhance wound healing is lacking and further high-quality randomised control trials are encouraged.

Principles of wound management, including debridement, wound bed preparation, and newer technologies involving alternation of wound physiology to facilitate healing, are of utmost importance when attempting to heal a chronic diabetes-related foot ulcer. However, the rising incidence and costs of diabetes-related foot ulcer management necessitate that interventions to enhance wound healing of chronic diabetes-related foot ulcers are supported by high-quality evidence of efficacy and cost effectiveness when used in conjunction with established aspects of gold-standard multidisciplinary care. This is the 2023 International Working Group on the Diabetic Foot (IWGDF) evidence-based guideline on wound healing interventions to promote healing of foot ulcers in persons with diabetes. It serves as an update of the 2019 IWGDF guideline.

We followed the GRADE approach by devising clinical questions and important outcomes in the Patient-Intervention-Control-Outcome (PICO) format, undertaking a systematic review, developing summary of judgements tables, and writing recommendations and rationale for each question. Each recommendation is based on the evidence found in the systematic review and, using the GRADE summary of judgement items, including desirable and undesirable effects, certainty of evidence, patient values, resources required, cost effectiveness, equity, feasibility, and acceptability, we formulated recommendations that were agreed by the authors and reviewed by independent experts and stakeholders.

From the results of the systematic review and evidence-to-decision making process, we were able to make 29 separate recommendations. We made a number of conditional supportive recommendations for the use of interventions to improve healing of foot ulcers in people with diabetes. These include the use of sucrose octasulfate dressings, the use of negative pressure wound therapies for post-operative wounds, the use of placental-derived products, the use of the autologous leucocyte/platelet/fibrin patch, the use of topical oxygen therapy, and the use of hyperbaric oxygen. Although in all cases it was stressed that these should be used where best standard of care was not able to heal the wound alone and where resources were available for the interventions.

These wound healing recommendations should support improved outcomes for people with diabetes and ulcers of the foot, and we hope that widescale implementation will follow. However, although the certainty of much of the evidence on which to base the recommendations is improving, it remains poor overall. We encourage not more, but better quality trials including those with a health economic analysis, into this area.

TS is a consultant for Inotec AMD Ltd., UK. The authors have no other conflicts of interest to declare.

Diabetic foot ulcers (DFU) pose a significant health risk in diabetic patients, with insufficient revascularization during wound healing being the primary cause. This study aimed to assess microvessel sprouting and wound healing capabilities using vascular endothelial growth factor (VEGF-A) and a modified fibroblast growth factor (FGF1).

An ex vivo aortic ring rodent model and an in vivo wound healing model in diabetic mice were employed to evaluate the microvessel sprouting and wound healing capabilities of VEGF-A and a modified FGF1 both as monotherapies and in combination.

The combination of VEGF-A and FGF1 demonstrated increased vascular sprouting in the ex vivo mouse aortic ring model, and topical administration of a combination of VEGF-A and FGF1 mRNAs formulated in lipid nanoparticles (LNPs) in mouse skin wounds promoted faster wound closure and increased neovascularization seven days post-surgical wound creation. RNA-sequencing analysis of skin samples at day three post-wound creation revealed a strong transcriptional response of the wound healing process, with the combined treatment showing significant enrichment of genes linked to skin growth.

f-LNPs encapsulating VEGF-A and FGF1 mRNAs present a promising approach to improving the scarring process in DFU.

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

A skin wound leads to the loss of skin integrity and the influx of pathogens into the tissue. Platelet-derived growth factors (PDGFs) are cytokines released from alpha granules during wound healing and interact with their cell surface receptors and activate signals involved in chemotaxis, growth, proliferation, and differentiation pathways. Due to the low stability of growth factors (GFs), a new peptide-derived PDGF-BB was designed, expressed in the Shuffle strain of E. coli, and purified by Ni-NTA agarose affinity column chromatography. The effect of fusion peptide was then evaluated on L929 fibroblast cells and animal models with skin lesions. In vitro, studies showed that the peptide led to an increase in the migration of fibroblast cells in the scratch assay. Its positive effect on wound healing was also observed in the skin-injured rats after 3, 7, and 12 days. A significant rise in neutrophils and granular tissue formation, re-epithelialization, angiogenesis, and collagen formation was exhibited on the third day of treatment when compared to the control group. The results showed that, despite reducing PDGF size, the fusion peptide was able to maintain at least some of the known functions attributed to full-length PDGF and showed positive results in wound healing.

Impaired wound healing is a common complication for diabetic patients and effective diabetic wound management remains a clinical challenge. Furthermore, a significant problem that contributes to patient morbidity is the suboptimal quality of healed skin, which often leads to reoccurring chronic skin wounds. Herein, a novel compound and biomaterial building block, panthenol citrate (PC), is developed. It has interesting fluorescence and absorbance properties, and it is shown that PC can be used in soluble form as a wash solution and as a hydrogel dressing to address impaired wound healing in diabetes. PC exhibits antioxidant, antibacterial, anti-inflammatory, and pro-angiogenic properties, and promotes keratinocyte and dermal fibroblast migration and proliferation. When applied in a splinted excisional wound diabetic rodent model, PC improves re-epithelialization, granulation tissue formation, and neovascularization. It also reduces inflammation and oxidative stress in the wound environment. Most importantly, it improves the regenerated tissue quality with enhanced mechanical strength and electrical properties. Therefore, PC could potentially improve wound care management for diabetic patients and play a beneficial role in other tissue regeneration applications.

Aim: To profile and study the proteins responsible for the beneficial effect of the TNF-α-induced human umbilical cord mesenchymal stem cells (hUCMSCs) secretome in wound healing. Methods: The hUCMSCs secretome was generated with (induced) or without (uninduced) TNF-α and was subsequently analyzed by liquid chromatography-mass spectrometry, immunoassay and in vitro scratch assay. Results: Proteomic analysis revealed approximately 260 proteins, including 51 and 55 unique proteins in the induced and uninduced secretomes, respectively. Gene ontology analysis disclosed that differential proteins in the induced secretome mainly involved inflammation-related terms. The induced secretome, consisting of higher levels of FGFb, VEGF, PDGF and IL-6, significantly accelerated wound closure and enhanced MMP-13 secretion in HaCaT keratinocytes. Conclusion: The secretome from induced hUCMSCs includes factors that promote wound closure.

Since the only and the milestone FDA approval of becaplermin gel (RegranexTM, 0.01% human recombinant PDGF-BB) as a (diabetic) wound healing therapeutic more than 25 years ago, no new therapeutic (excluding physical therapies, devices, dressings, anti-microbial agents, or other preventive treatments) for any type of wound healing has advanced to clinical applications. During the same period of time, the FDA has approved additional 250 new drugs for various human tumors, which were famously described as "wounds that do not heal". Two similar pathological conditions have experienced such a dramatic difference in therapeutics. More surprisingly, few in the wound healing community seem to be alarmed by this mysterious deficit. As it is often said, "damaging is far easier than re-building". In contrast to the primary duty of a cancer drug to damage a single molecule of the signaling network, a wound healing drug must be able to re-build the multi-level damages in the wound. No known single molecule alone is capable of repairing multi-cell-type and multi-pathway damages all at once. We argue that the previous single molecule-based strategy for developing wound healing therapeutics is profoundly flawed in theory. The future success of effective wound healing therapeutics requires a fundamental change in the paradigm.

Poor wound healing on the face and neck can lead to significant morbidity and dissatisfaction in facial plastic surgery. With current advances in wound healing management and commercially available biologic and tissue-engineered products, there are several options available to optimize acute wound healing and treat delayed or chronic wounds. This article summarizes some of the key principals and recent developments in wound healing research in addition to potential future advancements in the field of soft tissue wound healing.

Butyrate is a key bacterial metabolite that plays an important and complex role in modulation of immunity and maintenance of epithelial barriers. Its translation to clinic is limited by poor bioavailability, pungent smell, and the need for high doses, and effective delivery strategies have yet to realize clinical potential. Here, a novel polymeric delivery platform for tunable and sustainable release of butyrate consisting of a methacrylamide backbone with butyryl ester or phenyl ester side chains as well as mannosyl side chains, which is also applicable to other therapeutically relevant metabolites is reported. This platform's utility in the treatment of non-healing diabetic wounds is explored. This butyrate-containing material modulated immune cell activation in vitro and induced striking changes in the milieu of soluble cytokine and chemokine signals present within the diabetic wound microenvironment in vivo. This novel therapy shows efficacy in the treatment of non-healing wounds through the modulation of the soluble signals present within the wound, and importantly accommodates the critical temporal regulation associated with the wound healing process. Currently, the few therapies to address non-healing wounds demonstrate limited efficacy. This novel platform is positioned to address this large unmet clinical need and improve the closure of otherwise non-healing wounds.

Chronic non-healing wounds occur frequently in individuals affected by diabetes, yet standard-of-care treatment leaves many patients inadequately treated or with recurring wounds. MicroRNA (miR) expression is dysregulated in diabetic wounds and drives an anti-angiogenic phenotype, but miRs can be inhibited with short, chemically-modified RNA oligonucleotides (anti-miRs). Clinical translation of anti-miRs is hindered by delivery challenges such as rapid clearance and uptake by off-target cells, requiring repeated injections, excessively large doses, and bolus dosing mismatched to the dynamics of the wound healing process. To address these limitations, we engineered electrostatically assembled wound dressings that locally release anti-miR-92a, as miR-92a is implicated in angiogenesis and wound repair. In vitro, anti-miR-92a released from these dressings was taken up by cells and inhibited its target. An in vivo cellular biodistribution study in murine diabetic wounds revealed that endothelial cells, which play a critical role in angiogenesis, exhibit higher uptake of anti-miR eluted from coated dressings than other cell types involved in the wound healing process. In a proof-of-concept efficacy study in the same wound model, anti-miR targeting anti-angiogenic miR-92a de-repressed target genes, increased gross wound closure, and induced a sex-dependent increase in vascularization. Overall, this proof-of-concept study demonstrates a facile, translational materials approach for modulating gene expression in ulcer endothelial cells to promote angiogenesis and wound healing. Furthermore, we highlight the importance of probing cellular interactions between the drug delivery system and the target cells to drive therapeutic efficacy.

Diabetic foot ulcers (DFUs) are a severe and rapidly growing diabetic complication, but treating DFUs remains a challenge for the existing therapies are expensive and highly non-responsive. Recently, we discovered that a natural adhesive from snail mucus can promote skin wound healing. Herein, inspired by the finding, we developed a double-network hydrogel biomaterial that composed of snail glycosaminoglycan (AFG) and methacrylated gelatin (GelMA), in which AFG is the main bioactive component of snail mucus and GelMA provides a scaffold mimicking the proteins in snail mucus. The biomimetic hydrogel exhibited strong tissue adhesion, potent anti-inflammatory activity, and excellent biocompatibility. The biodegradable AFG/GelMA hydrogel markedly promoted chronic wound healing in both STZ-induced type 1 diabetic rat and db/db mouse models after a single treatment. Further mechanistic research showed that the hydrogel significantly attenuated inflammation by sequestrating pro-inflammatory cytokines, as well as downregulated their expression by inhibiting NF-ĸB signaling pathway, and it can also promote macrophage polarization to M2 phenotype. Taken together, the bioinspired hydrogel can effectively promote the transition of chronic wounds from inflammation to proliferation stage. These data suggest that the AFG/GelMA hydrogel is a promising therapeutic biomaterial for the treatment of chronic diabetic wounds.

This study examined the relative efficacy of growth factor therapies in healing diabetes-related foot ulcers (DFU).

PubMed and Cochrane databases were searched for randomized controlled trials testing growth factor therapies for treating DFU. The primary outcome was complete wound closure. Results were reported as relative risk (RR) ± 95% credible intervals (CrI). The risk of bias was assessed using Cochrane's RoB-2 tool.

A total of 31 RCTs involving 2174 participants were included. Only 13 of the trials (n = 924) reported on the aetiology of the ulcers (85.4% neuropathic and 14.6% ischaemic). Epidermal growth factor (RR 3.83; 95% CrI 1.81, 9.10), plasma-rich protein (PRP) (RR 3.36; 95% CrI 1.66, 8.03) and platelet-derived growth factor (PDGF) (RR 2.47; 95% CrI 1.23, 5.17) significantly improved the likelihood of complete ulcer healing compared to control. Sub-analyses suggested that PRP (3 trials - RR 9.69; 95% CrI 1.37, 103.37) and PDGF (6 trials - RR 2.22; 95% CrI 1.12, 5.19) significantly improved the likelihood of wound closure amongst trial mainly recruiting participants with neuropathic ulcers. Eleven trials had a low risk of bias, 9 had some concerns and 11 had a high risk of bias. Sub-analysis of trials with a low risk of bias suggested that none of the growth factors significantly improved ulcer healing compared with control.

This network meta-analysis found low-quality evidence that Epidermal growth factor, PRP and PDGF therapy improved DFU healing likelihood compared with control. Larger well-designed trials are needed.

Pressure injuries (PIs) are localized tissue damage resulting from prolonged compression or shear forces on the skin or underlying tissue, or both. Different stages of PIs share common features include intense oxidative stress, abnormal inflammatory response, cell death, and subdued tissue remodeling. Despite various clinical interventions, stage 1 or stage 2 PIs are hard to monitor for the changes of skin or identify from other disease, whereas stage 3 or stage 4 PIs are challenging to heal, painful, expensive to manage, and have a negative impact on quality of life. Here, we review the underlying pathogenesis and the current advances of biochemicals in PIs. We first discuss the crucial events involved in the pathogenesis of PIs and key biochemical pathways lead to wound delay. Then, we examine the recent progress of biomaterials-assisted wound prevention and healing and their prospects.