Metalloproteinases and Wound Healing

SIRT1/DNMT3B-mediated epigenetic gene silencing in response to phytoestrogens in mammary epithelial cells

We performed an integrated analysis of genome-wide DNA methylation and expression datasets in normal cells and healthy animals exposed to polyphenols with estrogenic activity (i.e. phytoestrogens). We identified that phytoestrogens target genes linked to disrupted cellular homeostasis, e.g. genes limiting DNA break repair (RNF169) or promoting ribosomal biogenesis (rDNA). Existing evidence suggests that DNA methylation may be governed by sirtuin 1 (SIRT1) deacetylase via interactions with DNA methylating enzymes, specifically DNMT3B. Since SIRT1 was reported to be regulated by phytoestrogens, we test whether phytoestrogens suppress genes related to disrupted homeostasis via SIRT1/DNMT3B-mediated transcriptional silencing. Human MCF10A mammary epithelial cells were treated with phytoestrogens, pterostilbene (PTS) or genistein (GEN), followed by analysis of cell growth, DNA methylation, gene expression, and SIRT1/DNMT3B binding. SIRT1 occupancy at the selected phytoestrogen-target genes, RNF169 and rDNA, was accompanied by consistent promoter hypermethylation and gene downregulation in response to GEN, but not PTS. GEN-mediated hypermethylation and SIRT1 binding were linked to a robust DNMT3B enrichment at RNF169 and rDNA promoters. This was not observed in cells exposed to PTS, suggesting a distinct mechanism of action. Although both SIRT1 and DNMT3B bind to RNF169 and rDNA promoters upon GEN, the two proteins do not co-occupy the regions. Depletion of SIRT1 abolishes GEN-mediated decrease in rDNA expression, suggesting SIRT1-dependent epigenetic suppression of rDNA by GEN. These findings enhance our understanding of the role of SIRT1-DNMT3B interplay in epigenetic mechanisms mediating the impact of phytoestrogens on cell biology and cellular homeostasis.

Endothelial cell supplementation promotes xenograft revascularization during short-term ovarian tissue transplantation

The ischemic/hypoxic window after Ovarian Tissue Transplantation (OTT) can be responsible for the loss of more than 60 % of follicles. The implantation of the tissue supplemented with endothelial cells (ECs) inside dermal substitutes represents a promising strategy for improving graft revascularization. Ovarian biopsies were partly cryopreserved and partly digested to isolate ovarian ECs (OVECs). Four dermal substitutes (Integra®, made of bovine collagen enriched with chondroitin 6-sulfate; PELNAC®, composed of porcine collagen; Myriad Matrix®, derived from decellularized ovine forestomach; and NovoSorb® BMT, a foam of polyurethane) were compared for their angiogenic bioactive properties. OVECs cultured onto the scaffolds upregulated the expression of angiogenic factors, supporting their use in boosting revascularization. Adhesion and proliferation assays suggested that the most suitable scaffold was the bovine collagen one, which was chosen for further in vivo experiments. Cryopreserved tissue was transplanted onto the 3D scaffold in immunodeficient mice with or without cell supplementation, and after 14 days, it was analyzed by immunofluorescence (IF) and X-ray phase contrast microtomography. The revascularization area of OVECs-supplemented tissue was doubled (7.14 %) compared to the scaffold transplanted alone (3.67 %). Furthermore, tissue viability, evaluated by nuclear counting, was significantly higher (mean of 169.6 nuclei/field) in the tissue grafted with OVECs than in the tissue grafted alone (mean of 87.2 nuclei/field). Overall, our findings suggest that the OVECs-supplementation shortens the ischemic interval and may significantly improve fertility preservation procedures.

Transcriptional Profiling of SSEA-1+ Endometrial Epithelial Progenitor Cells Highlights Their Role in Endometrial Regeneration, Remodeling, and Homeostasis

Stage-specific embryonic antigen-1 (SSEA-1)+ endometrial epithelial cells (EECs) assume the postulated stem/progenitor cell niche within the human endometrium. Previous studies have demonstrated that isolated SSEA-1+ cells have a higher capacity to generate organoids in a three-dimensional matrix, a lower steroid hormone receptor expression, and higher telomerase activity with longer telomere lengths. Here, we present the transcriptomic profile of isolated SSEA-1+ EECs from eight endometrial biopsies compared to SSEA-1- EECs. Transcriptome and pathway analysis indicate that SSEA-1+ EECs play an important role in endometrial regeneration, remodeling and neovascularization as expected from a basal progenitor population. We show that SSEA-1+ EECs play a role in endometrial tissue homeostasis and tumor suppression, and bioinformatically identify potential upstream regulators such as SPDEF and TGFB1, which may be involved in these mechanisms. In vitro EEC organoid models also demonstrate SSEA-1+ EECs to exhibit estrogen responsive proliferation evidenced by stronger immunostaining for progesterone receptor and Ki-67. Our data further suggest a more quiescent, less hormone responsive phenotype for SSEA-1+ EECs that co-localize to SOX9+ EECs within in silico analysis, thus validating previous studies.

Systematic Review of Relevant Biomarkers for Human Connective Tissue Repair and Healing Outcome: Implications for Understanding Healing Processes and Design of Healing Interventions

Objective: The healing process following connective tissue (CT) injuries is complex, resulting in variable and often suboptimal outcomes. Patients undergoing CT repair frequently experience healing failures, compromised function, and chronic degenerative diseases. The identification of biomarkers to guide improved clinical outcomes after CT injuries remains an emerging but promising field. [Figure: see text] [Figure: see text] Design: Systematic review. Data sources: Databases, including PubMed, MEDLINE Ovid, Web of Science, and Google Scholar, were searched up to August 2024. Eligibility criteria: To achieve the research objective, randomized control trials, cohort studies, and case-control studies on biomarkers associated with CT repair and healing outcomes were selected. The present analysis was confined to clinical and preclinical models, excluding imaging studies. The entire process of this systematic review adhered strictly to the guidelines outlined in the Preferred Reporting Items for Systematic Review and Meta-Analyses protocol checklist. Results: A total of 1,815 studies on biomarkers of CT repair were initially identified, with 75 studies meeting eligibility criteria and 55 passing quality assessments. For biomarkers associated with CT healing outcomes, 281 studies were considered, with 30 studies meeting eligibility criteria and 24 passing quality assessments. Twenty-one overlapping studies investigated the effects of biomarkers on both CT repair and healing outcomes. Specific biomarkers identified, and ranked from highest to lowest quality, include complement factor D, eukaryotic elongation factor-2, procollagen type I N-terminal propetide, procollagen type III N-terminal propetide, lactate, pyruvate, platelet-derived growth factor-BB, tissue inhibitor of metalloproteinase-3 (TIMP-3), cysteine-rich protein-1, plastin-3, periostin, protein S100-A11, vimentin, matrix metalloproteinases (MMP-2, MMP-7, and MMP-9), hepatocyte growth factor, interferon-γ, interleukins (IL-6, IL-8, and IL-10), MMP-1, MMP-3, tumor necrosis factor-α, fibroblast growth factor-2, IL-1α, chondroitin-6-sulfate, inter-alpha-trypsin inhibitor heavy chain-4, transforming growth factor-beta 1, vascular endothelial growth factor, C-C chemokine receptor 7, C-C chemokine ligand 19, IL-1β, IL-1Ra, IL-12p40, granulocyte-macrophage colony-stimulating factor (GM-CSF), and TIMP-1. Conclusions: All of the 37 identified potential biomarkers demonstrated regulatory effects on CT repair and mediated healing outcomes. Notably, the identified biomarkers from human studies can potentially play an essential role in the development of targeted treatment protocols to counteract compromised healing and can also serve as predictors for detecting CT healing processes and long-term outcomes.

The design principle of natural polysaccharide hydrogels for promoting wound healing: a prospective review

Acute skin injuries and chronic non-healing wounds are common in daily life, posing significant physical trauma to patients and creating substantial social and economic burdens. Polysaccharide-based hydrogels not only maintain optimal moisture levels for wound recovery but also act as effective barriers against bacterial infection. Polysaccharides, with their unique properties such as biocompatibility, biodegradability, and non-toxicity, are promising materials for constructing hydrogels designed for wound healing. This review discusses wound physiology, key design factors for wound-healing hydrogels, and the fundamental principles of hydrogel gelation. It also provides an overview of the current applications of polysaccharide-based hydrogels-including those derived from hyaluronic acid, chitosan, sodium alginate, cellulose, glucose, and starch-as advanced wound dressings. Finally, the review outlines current challenges and future research directions for polysaccharide-based hydrogels in wound healing, aiming to inspire further exploration and innovation in this field.

Research progress on the role of fascia in skin wound healing

The skin, the human body's largest organ, is perpetually exposed to environmental factors, rendering it vulnerable to potential injuries. Fascia, a vital connective tissue that is extensively distributed throughout the body, fulfils multiple functions, including support, compartmentalization, and force transmission. The role of fascia in skin wound healing has recently attracted considerable attention. In addition to providing mechanical support, fascia significantly contributes to intercellular signalling and tissue repair, establishing itself as a crucial participant in wound healing. This review synthesises the latest advancements in fascia research and its implications for skin wound healing.

Proteomic Insights into Human Limbal Epithelial Progenitor-Derived Small Extracellular Vesicles

Limbal epithelial stem/progenitor cells (LEPC), supported by limbal mesenchymal stromal cells (LMSC) and limbal melanocytes (LM) within a specialized niche, are responsible for maintaining the corneal epithelium. Small extracellular vesicles (sEV) emerged as critical mediators of intercellular communication in various stem cell niches, yet their role in maintaining human limbal niche homeostasis remains poorly understood. In this study, tangential flow filtration and size exclusion chromatography were used to isolate sEV from LEPC-, LMSC- and LM-conditioned media. The isolated sEV from LEPC exhibited properties characteristic for sEV as confirmed by nanoparticle tracking analysis for size and concentration, by electron microscopy for morphology, and by western blot analysis of canonical EV markers including the cell-specific protein (cytokeratin 17/19). Quantitative and comparative proteomic profiling revealed distinct molecular signatures of LEPC-derived sEV, enriched in factors associated with keratinocyte development, extracellular matrix organization, and niche regulation. These findings suggest that LEPC-derived sEV may serve as important signaling mediators within the limbal niche microenvironment, though additional studies are needed to determine their specific functional roles in maintaining niche homeostasis.

Sepia Melanin for the Local Deactivation of Matrix Metalloproteinases

Matrix metalloproteinases (MMPs) are a family of zinc-dependent enzymes that degrade the extracellular matrix and play essential functions in wound healing and tissue remodeling. However, the long-term overexpression of MMPs is associated with a chronic wound environment. Treatments that locally deactivate MMPs have been proposed to improve the outcomes of nonhealing chronic wounds. In this Letter, sepia melanin, a natural biopigment, is explored for the deactivation of MMPs, through chelation of zinc ions. Melanins have chemical functional groups to bind to various metal ions, which we demonstrate can be exploited for the deactivation of MMPs. Melanin's selectivity for zinc ions, and ability to deactivate MMPs that are associated with chronic wounds (MMP-1, MMP-2, and MMP-9) are examined, and its potential application in wound healing is demonstrated by functional in vitro tissue assays, mimicking the nonhealing wound environment. This is the first demonstration of the use of melanin for MMP deactivation.

Accelerated diabetic wound healing using a chitosan-based nanomembrane incorporating nanovesicles from Aloe barbadensis, Azadirachta indica, and Zingiber officinale

Diabetic wounds pose a substantial clinical challenge due to delayed healing, persistent inflammation, and susceptibility to infections. This study investigates the therapeutic efficacy of a chitosan-polyvinyl alcohol nanomembrane (OXY-NMAloe) plant-derived extracellular vesicles enriched with extracellular vesicles derived from Aloe barbadensis, Azadirachta indica, and Zingiber officinale. Chitosan, a natural biological macromolecule, forms the nanomembrane's matrix, contributing to its flexibility, porosity, and structural integrity, essential for maintaining optimal wound hydration and supporting tissue regeneration. In in vivo studies on streptozotocin-induced diabetic rats, OXY-NMAloe significantly accelerated wound closure by approximately 23 % compared to just 7 % in the control-treated group, even after one day. This effect was achieved by modulating pro-inflammatory cytokines, activating collagen synthesis, and restoring mitochondrial function. The membrane also inhibited matrix metalloproteinase overexpression, reducing excessive extracellular matrix degradation by ~40 % and promoting tissue regeneration. Furthermore, OXY-NMAloe demonstrated potent antimicrobial activity against Staphylococcus aureus and Pseudomonas aeruginosa, decreasing microbial colonization and fostering a favorable healing environment. By integrating the structural properties of chitosan with the bioactivity of plant-derived extracellular vesicles, the nanomembrane offers a multifunctional therapeutic platform for accelerating tissue repair and addressing key challenges in diabetic wound management.

Immunomarker profiling in human chronic wound swabs reveals IL-1 beta/IL-1RA and CXCL8/CXCL10 ratios as potential biomarkers for wound healing, infection status and regenerative stage

BACKGROUND

Chronic wounds, such as diabetic foot ulcers, venous leg ulcers, and post-surgical wound healing disorders pose a significant challenge due to prolonged healing, risk of infection, and impaired quality of life. Persistent inflammation and impaired tissue remodeling are common in these wounds. Traditional diagnostic methods, including visual inspection and microbiological cultures, offer limited insight into the wound micro-environment. Immunomarker profiling could provide a deeper understanding of the molecular mechanisms underpinning wound healing, offering potential biomarkers for infection status and healing progression.

METHODS

This observational, multi-center cohort study, part of the 'Wound-BIOME' project, analyzed 110 swab samples from patients with acute and chronic wounds using multiplex immunoassays. Clinical parameters such as wound type, healing status, regeneration stage, and microbial burden were recorded. Total protein concentration was assessed, and 35 key immunomarkers, including cytokines (e.g. IL- 1α, IL- 1β), chemokines (CCL2, CXCL8, CXCL10), growth factors (FGF- 2, VEGF) and matrix metalloproteinases (MMP- 7, MMP- 9, MMP- 13), were quantified. Statistical analyses were performed to correlate immunomarker levels with clinical outcomes.

RESULTS

Pro-inflammatory markers, such as IL- 1β, IL- 18 and chemokines like CCL2 and CXCL8, were significantly elevated in non-healing and infected wounds compared to healing wounds. The study identified two new immunomarker ratios - IL- 1β/IL- 1RA and CXCL8/CXCL10 - as potential predictors of wound healing status. The IL- 1β/IL- 1RA ratio showed the highest accuracy for distinguishing healing from non-healing wounds (AUC = 0.6837), while the CXCL8/CXCL10 ratio was most effective in identifying infection (AUC = 0.7669).

CONCLUSIONS

Immunomarker profiling via wound swabbing offers valuable insights into the wound healing process. Elevated levels of pro-inflammatory cytokines and MMPs are associated with chronic inflammation and impaired healing. The IL- 1β/IL- 1RA and CXCL8/CXCL10 ratios emerge as promising biomarkers to distinguish between infection and inflammation, with potential in targeted wound care. Further studies are needed to validate these findings and implement them in clinical practice.

Evaluating and comparing the effects of paracetamol and ibuprofen on wound healing, MMP-9, and TGF-β1 levels in patients following upper third molar tooth extraction

BACKGROUND

Paracetamol and ibuprofen are commonly prescribed pain relievers used in dental treatments, but their use can delay wound healing and lead to malunion and weaken the strength of newly formed bones. This randomized controlled clinical trial aimed to evaluate the wound healing (WH) and anti-inflammatory effects of paracetamol and ibuprofen on tooth extraction wounds in patients.

METHODS

This study involved a total of 20 patients who required removal of their fully erupted upper third molar under local anaesthesia at the Oral and Maxillofacial Surgery Clinic, Faculty of Dentistry, Chiang Mai University. The study subjects were divided into two groups of 10 patients each who were prescribed 400 mg of ibuprofen or 500 mg of paracetamol for seven days. Subsequently, WH was evaluated and the resulting proportions were compared using Landry Turnbull and Howley Index (LTHI) scores. Salivary matrix metalloproteinase 9 (MMP-9) and transforming growth factor beta1 (TGF-β1) concentrations were used as proinflammatory indicators. Accordingly, the WH values and the resulting proportions were compared using Fisher's exact test with a confidence interval (CI) of 95% (P < 0.05). The concentrations of MMP-9 and TGF-β1 were measured using ELISA and compared using the Mann‒Whitney U test at 95% CI (P < 0.05). The obtained statistical values were then analysed and interpreted accordingly.

RESULTS

LTHI values on days 3 and 7 after tooth extraction were not significantly different between the two treatment groups. Salivary MMP-9 levels were lower in the paracetamol-treated group than in the ibuprofen-treated group (P < 0.01) on day 3 only. The LTHI concentration was also negatively correlated (r = -0.433) with the MMP-9 concentration (P < 0.05) but was positively correlated (r = 0.369) with the salivary TGF-β1 concentration (P < 0.05). Interestingly, MMP-9 was negatively correlated with TGF-β1 in the ibuprofen treatment group (r2 = -0.351).

CONCLUSION

Ibuprofen can inhibit the inflammatory process and delay healing in the extraction socket. After discontinuation of medication, no differences were observed in the healing effects between the paracetamol and ibuprofen groups.

TRIAL REGISTRATION

The clinical trial was retrospectively registered at the Australian New Zealand Clinical Trial Registry (ANZCTR) NHMRC Clinical Trials Centre, Camperdown, Australia (Registry URL: https://www.anzctr.org.au ) (Registration number: ACTRN12624000595516 Date: 9/5/2024).

Enhancing immunotherapy with tumour-responsive nanomaterials

The targeted delivery of immunotherapies to tumours using tumour-responsive nanomaterials is a promising area of cancer research with the potential to address the limitations of systemic administration such as on-target off-tumour toxicities and a lack of activity owing to the immunosuppressive tumour microenvironment (TME). Attempts to address these challenges include the design and functionalization of nanomaterials capable of releasing their cargoes in response to specific TME characteristics, thus facilitating the targeted delivery of immune-checkpoint inhibitors, cytokines, mRNAs, vaccines and, potentially, chimaeric antigen receptors as well as of agents that modulate the extracellular matrix and induce immunogenic cell death. In this Review, we describe these various research efforts in the context of the dynamic properties of the TME, such as pH, reductive conditions, reactive oxygen species, hypoxia, specific enzymes, high levels of ATP and locoregional aspects, which can be leveraged to enhance the specificity and efficacy of nanomaterial-based immunotherapies. Highlighting preclinical successes and ongoing clinical trials, we evaluate the current landscape and potential of these innovative approaches. We also consider future research directions as well as the most important barriers to successful clinical translation, emphasizing the transformative potential of tumour-responsive nanomaterials in overcoming the barriers that limit the activity of traditional immunotherapies, thus improving patient outcomes.

Polysaccharides, proteins and DNA based stimulus responsive hydrogels promoting wound healing and repair: A review

The healing of various wounds remains a serious challenge in the medical field, hydrogel has high hydrophilicity and biocompatibility due to its unique network structure, which shows a strong advantage in the field of wound healing. Stimulus responsive hydrogels are particularly effective，which can control the material properties according to the external stimulus source, and provide more targeted treatment for different wounds. Here, we review physiological mechanisms of wound healing and the relationship between polysaccharides, proteins and DNA based stimulus responsive hydrogels and wound healing, materials commonly used of polysaccharides, proteins and DNA based stimulus responsive hydrogels, mechanisms of stimulus responsive hydrogels formation and network structure types, common properties of polysaccharides, proteins and DNA based stimulus responsive hydrogels for promoting wound healing and discuss their applications in medicine. Finally, the limitations and application prospects of polysaccharides, proteins and DNA based stimulus responsive hydrogels were discussed and evaluated. The review focuses on the biomedical use of polysaccharides, proteins and DNA based stimulus responsive hydrogels in wound healing and repair, and provides insights for the development of clinical related materials.

A high-fat diet changes the interaction of the extracellular matrix, cytokines, and growth factors in gastric ulcer repair

BACKGROUND

Obesity is characterized by persistent low-grade inflammation that alters the gastrointestinal system and healing process. The link between obesity and the prevalence of stomach ulcers has not yet been fully established.

AIMS

We investigated the healing features of gastric lesions in male Swiss mice fed a standard diet (SD) or high-fat diet (HFD) using morphometric, biochemical, and molecular parameters.

METHODS

After 12 weeks on different diets, the animals underwent acetic acid-induced stomach ulcer surgery. To evaluate healing patterns, the stomachs of the animals were studied at five post-induction times, including the early, middle, and late phases of healing (1, 3, 7, 10, and 14 days). Morphometric features, activity of matrix metalloproteinases 2 and 9 (MMP-2 and 9), and measurement of inflammatory and growth factors were investigated using multiplex immunoassays.

RESULTS

Compared with the SD group, the HFD group demonstrated slowing of the early healing process. During the initial phase of the healing process, the SD group had significantly higher levels of EGF, VEGF-A, and VEGF-D than the HFD group. In the intermediate phase, only the SD group showed a 70 % increase in the regeneration area compared with the initial phase of the procedure. In this phase, the SD group also had higher levels of MMP-9, VEGF-D, and HGF than the HFD group.

CONCLUSIONS

HFD can have a negative impact on the healing process of gastric ulcers in animals by delaying repair in gastric tissue when compared with animals consuming SD.

Effects of Different Self-Adhesive Resin Cements and Curing Through Zirconia on Gingival Fibroblasts

INTRODUCTION

Self-adhesive resin cements (SARCs) are widely used for fixed prostheses. These cements and their eluted products may affect periodontal tissues. This study aimed to investigate the response of human gingival fibroblasts (HGFs) to eluates from SARCs in vitro, simulating clinical conditions after prosthesis fixation, to gain insights into their potential effects on gingival health.

METHODS

Two SARCs, RelyX U200 (RX) and Maxcem Elite Chroma (MC), were polymerised according to the manufacturer's protocols using various curing methods (light-cured, light-cured through 1- or 2 mm zirconia, and self-cured). HGFs were exposed to cement eluates at different concentrations. Cell viability, vitality, wound healing, and gene expression were assessed at different time points.

RESULTS

Self-cured MC and MC cured through 2-mm zirconia (both undiluted and 1:5 dilution) significantly decreased HGFs' viability. Lower cell viability and vitality were detected in MC compared with RX. Wound healing was delayed in cells treated with MC cured through zirconia compared to those cured with direct light, whereas zirconia had no effect on cells treated with RX. The expression of NRF2, a key regulator of cellular defence against oxidative and toxic insults, showed an increasing trend in cells treated with MC compared to RX. This finding suggests that MC may induce more oxidative stress than RX, leading to a more pronounced inflammatory response in HGFs and aligning with the observed delay in wound healing.

CONCLUSION

The use of MC, especially when cured through zirconia, may negatively impact gingival tissue health, highlighting the importance of carefully selecting cement types and curing methods in clinical practice.

CLINICAL RELEVANCE

This study highlights the potential risks of using MC, especially when cured through zirconia, which may impair gingival tissue health and delay wound healing. Proper choice of cement and curing methods is essential for optimal patient outcomes.

Phosphocreatine-mediated enhancement of mitochondrial function for accelerated healing of diabetic foot ulcers through the PGC-1α-NRF-1 signaling pathway

Diabetic foot ulcers (DFUs) pose a significant clinical challenge due to their slow healing and high risk of complications, which severely affect patient quality of life. Central to the delayed healing observed in DFUs is mitochondrial dysfunction, a critical factor impairing cellular repair processes. Phosphocreatine (PCr), a vital molecule involved in cellular energy buffering and ATP regeneration, has recently emerged as a promising therapeutic candidate for ameliorating mitochondrial dysfunction and enhancing tissue repair. This study explores the novel therapeutic potential of PCr in restoring mitochondrial function and accelerating wound healing in DFUs through both in vitro and in vivo models. Using hyperglycemic human umbilical vein endothelial cells (HUVECs) as an in vitro model and a streptozotocin (STZ)-induced diabetic rat model as an in vivo, we evaluated the impact of PCr treatment on mitochondrial activity and wound repair. PCr treatment notably upregulated key mitochondrial biogenesis markers, including peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α) and nuclear respiratory factor 1 (NRF-1), indicating a restoration of mitochondrial function. In vivo, PCr-treated diabetic rats demonstrated significantly accelerated wound closure, enhanced granulation tissue formation, and reduced inflammatory cell infiltration. These findings underscore PCr's potential to address mitochondrial dysfunction and expedite wound healing in DFUs. This study offers promising new insights into PCr as a targeted therapeutic intervention, paving the way for improved patient outcomes in managing diabetic foot ulcers.

Differential Cellular Responses to Class I and II Sphingomyelinase D: Unraveling the Mechanisms of Loxosceles Venom-Induced Dermonecrosis and Potential Therapeutic Targets

Dermonecrosis resulting from Loxosceles spider envenomation, primarily driven by the enzyme sphingomyelinase D (SMase D), is characterized by severe inflammation and nonhealing wounds. SMases can be classified as Class I or II based on their structural characteristics. Class I exhibits greater dermonecrotic activity than Class II; however, the intracellular mechanisms responsible for this difference remain poorly understood. The differential transcriptomics analysis of human keratinocytes treated with each toxin revealed that Class I primarily activates pathways associated with proteolytic activity and apoptosis. In contrast, Class II uniquely upregulates key genes, including PIM-1, MCL-1, PAI-1, p21, and c-FOS, which support cell survival and inhibit apoptosis. These pathways also facilitate tissue repair and keratinocyte proliferation during wound healing, particularly through signaling mechanisms involving Substance P and VEGF-A. RT-qPCR confirmed these findings, with protein level evaluations indicating the sustained upregulation of VEGF-A exclusively in keratinocytes treated with Class II. We identified Substance P and VEGF-A as potential therapeutic targets for managing cutaneous loxoscelism, providing valuable insights into the cellular mechanisms underlying the distinct toxic effects of the two SMase D isoforms. By elucidating these pathways, this study enhances our understanding of loxoscelism's pathophysiology and highlights strategies for therapeutic intervention in dermonecrotic injuries caused by spider venom.

Characterization of a Bioactive Chitosan Dressing: A Comprehensive Solution for Different Wound Healing Phases

Wound management has made significant advances over the past few decades, particularly with the development of advanced dressings that facilitate autolytic debridement, the absorption of wound exudate, and protection from external bacteria. However, finding a single dressing that effectively addresses all four phases of wound healing─hemostasis, inflammation, proliferation, and remodeling─remains a major challenge. Additionally, biofilms in chronic wounds pose a substantial obstacle by shielding microbes from topical antiseptics and antibiotics, thereby delaying the healing process. This study evaluates the wound-healing properties of a commercially available bioactive microfiber gelling (BMG) dressing made from chitosan alongside commercially available silver-loaded carboxymethyl cellulose (CMC-Ag) dressing, carboxymethyl cellulose dressing (CMC) and cotton gauze. In vitro testing demonstrated that the BMG dressing significantly exhibited superior fluid absorption and exudate-locking properties compared with the CMC-Ag dressing. Additionally, the BMG dressing effectively sequestered and eradicated wound-relevant pathogenic microorganisms, including drug-resistant bacteria. Its bioactive properties were further highlighted by its ability to enhance platelet-derived growth factor (PDGF) expression and sequester matrix metalloproteases (MMPs). Overall, this study highlights the effectiveness of the BMG dressing in wound management, particularly in exudate absorption and antimicrobial activity, demonstrating its relevance in wound care.

Phytochemical Composition and Wound Healing Properties of Echinacea angustifolia DC. Root Hydroalcoholic Extract

The therapeutic potential of natural products has led to the exploitation of phytocomplexes for treating various skin conditions, including wounds. Echinacea angustifolia DC. has traditionally been used for wound healing, burns, and other ailments. In this study, dried roots of E. angustifolia were extracted using a hydroalcoholic solution, and the phytochemical composition was analyzed through HPLC-DAD. The polyphenol and polysaccharide content, along with in vitro antioxidant and anti-tyrosinase properties, were evaluated. The biological effect of E. angustifolia extract was evaluated on the 3T3-L1 cell line. HPLC-DAD analysis confirmed the presence of several polyphenols, particularly caffeic acid derivatives, with echinacoside as the predominant compound, exhibiting strong antioxidant properties. The extract demonstrated no cytotoxic effect on 3T3-L1 cells, and it showed a protective effect by increasing the migration process in an in vitro scratch wound healing test, together with echinacoside and allantoin, which were used as references. Furthermore, the extract reduced the expression of proinflammatory cytokines and promoted that of proteins that accelerate wound closure, such as TGF-β1. The present study demonstrates the potential wound healing properties and the antioxidant and anti-inflammatory activity of E. angustifolia root hydroalcoholic extract, giving a scientific rationale for its traditional use.

Elevation of Plasma IL-15 and RANTES as Potential Biomarkers of Healing in Chronic Venous Ulcerations: A Pilot Study

Chronic wounds present a large burden to our healthcare system and are typically marked by a failure to transition out of the inflammatory phase of wound healing. Venous leg ulcers (VLUs) represent the largest portion of chronic wounds. A pilot study of eleven (11) patients with VLUs seen over a 12-week period was undertaken utilizing RNA sequencing of wound biopsies and plasma cytokine levels to determine if biomarkers could be identified that would distinguish between wounds which heal versus those that do not. Chronic wounds were found to have increased expression of genes relating to epithelial-to-mesenchymal transition (EMT), cartilage and bone formation, and regulation of apical junction. Plasma cytokine levels showed predictive potential for IL-15 and RANTES, which were found to increase over time in patients with healed wounds. Further research is needed to validate these biomarkers as well as additional study of other chronic wound models, such as diabetic foot ulcers (DFUs).

The Role of CXCR2, MMP-2, and MMP-9 in the Pathogenesis of Placenta Accreta: A Molecular Expression Study

Background and Objectives: The pathogenesis of placenta accreta spectrum disorder (PASD) is influenced by the inflammatory process. Therefore, the examination of biomarkers related to the inflammatory process, namely matrix metalloproteinase (MMP) and CXC motif chemokine receptor 2 (CXCR2), is expected to bring researchers to a bright spot regarding the pathogenesis of PASD. This study analyzes the role of CXCR2, MMP-2, and MMP-9 in the pathogenesis of PASD. Materials and Methods: An observational study with a case-control design was conducted to assess differences in the mean density of CXCR2, MMP-2, and MMP-9 immunostaining in placental and uterine tissue in 17 patients with PASD and 34 patients without PASD at the Department of Obstetrics and Gynecology, Dr. Mohammad Hoesin Hospital Palembang. The expression of CXCR2, MMP-2, and MMP-9 was measured by immunohistochemistry analysis. The data were analyzed using STATA version 15. Results: There were no significant differences in the mean levels of MMP-2 expression in patients with and without PASD. There were significant differences in the expression of placental CXCR2 (p = 0.003), uterine CXCR2 (p < 0.001), and uterine MMP-9 (p = 0.018) in patients with and without PASD. Conclusions: CXCR2 and MMP-9 may play a role in the pathogenesis of PASD.

Repurposing diacerein for the treatment of chronic wounds in recessive-dystrophic epidermolysis bullosa patients by modulating matrix metalloproteinase-9 expression

Recessive dystrophic epidermolysis bullosa (RDEB) is caused by mutations in COL7A1, leading to loss or dysfunction of type-VII collagen (C7), a protein essential for skin stability. Clinically, patients suffer from severe skin blistering, chronic or recurrent wounds, and scarring, which predispose to early onset of aggressive squamous cell carcinoma. Previous studies showed that RDEB-keratinocytes (RDEB-KC) express high levels of matrix-metalloproteinase 9 (MMP-9), a molecule known to play a crucial role in wound chronification if dysregulated. We investigated the potential of diacerein, a small molecule that interferes with the MMP-9 regulatory pathway, to improve wound healing in a 5-year old RDEB patient presenting with chronic, generalized skin involvement unresponsive to previous treatment approaches. Upon 4 weeks of topical therapy applied to the patient's back, parents reported a nearly complete wound closure and a significant increase in quality of life. We also provide evidence that diacerein treatment of patient keratinocytes results in a downregulation of MMP-9 expression, accompanied by a reduction in their ability to degrade a fibrinogen matrix. These data characterize diacerein as a potential candidate for improving wound healing in RDEB through its impact on inflammatory as well as epithelial cells.

Wound Healing Splinting Devices for Faster Access and Use

With the goal of studying skin wound healing and testing new drug treatments to enhance wound healing in rodent models, there is a clear need for improved splinting techniques to increase surgical efficiency and support routine wound monitoring. Splinted wound healing models humanize wound healing in rodents to prevent contraction and instead heal through granulation tissue deposition, increasing the relevance to human wound healing. Current technologies require suturing and heavy wrapping, leading to splint failure and cumbersome monitoring of the wound. In this study, we developed a splint with resealable cap system that provides ease of access for wound inspection, therapeutic treatment delivery, and routine wound imaging without the need to unwrap and wrap the animal. Meanwhile, to overcome the challenges associated with suturing, we also developed adherent splints that can be applied to both hairless or haired mice with minimal wrapping. Both technologies are expected to improve and encourage the adoption of splinted wound healing models.

The regulatory role of BMP9 on lipopolysaccharide-induced matrix metalloproteinases in human stem cells from the apical papilla

OBJECTIVE

The aim of this study was to investigate changes in the expression of members of the matrix metalloproteinases (MMPs) family in response to lipopolysaccharide (LPS) stimulation and to investigate the regulatory effects of BMP9 on MMPs.

DESIGN

The extracted human stem cells from the apical papilla (hSCAPs) were identified by flow cytometry, Alizarin Red staining, Oil Red O staining, and alkaline phosphatase staining. The appropriate LPS concentration for inducing inflammation in hSCAPs was determined using real-time quantitative PCR (RT-qPCR) and Cell Counting Kit-8 (CCK-8) assays. MMP expression in LPS-stimulated hSCAPs was evaluated by RT-qPCR. BMP9 was overexpressed in hSCAPs via recombinant adenovirus, and its effects on MMP regulation were assessed using RT-qPCR, Western blotting, and ELISA. All experiments were conducted in vitro. Data were analyzed by one-way ANOVA followed by Tukey's post-hoc comparison, with p < 0.05 considered significant.

RESULTS

The results showed that on the 3rd and 5th day after LPS stimulation, the expression of MMP-1, MMP-2, MMP-3, MMP-8, MMP-9, MMP-10, MMP-12, and MMP-13 in hSCAPs was significantly upregulated. On the 7th day after LPS induction, the expression of MMP-3, MMP-8, MMP-9 and MMP-13 in hSCAPs was significantly increased. When BMP9 was overexpressed in hSCAPs, the elevated MMPs were inhibited to varying degrees.

CONCLUSIONS

In the LPS-induced inflammatory environment, certain MMPs are elevated in hSCAP, with MMP-13 being the most significant. Overexpression of BMP9 can significantly inhibit elevated MMPs, suggesting that BMP9 may provide new insights and targets for the treatment of periapical periodontitis.

Development of a porcine model of skin and soft-tissue infection caused by Staphylococcus aureus, including methicillin-resistant strains suitable for testing topical antimicrobial agents

BACKGROUND

In view of the ever-increasing representation of Staphylococcus spp. strains resistant to various antibiotics, the development of in vivo models for evaluation of novel antimicrobials is of utmost importance.

METHODS

In this article, we describe the development of a fully immunocompetent porcine model of extensive skin and soft tissue damage suitable for testing topical antimicrobial agents that matches the real clinical situation. The model was developed in three consecutive stages with protocols for each stage amended based on the results of the previous one.

RESULTS

In the final model, 10 excisions of the skin and underlying soft tissue were created in each pig under general anesthesia, with additional incisions to the fascia performed at the base of the defects and immediately inoculated with Staphylococcus aureus suspension. One pig was not inoculated and used as the negative control. Subsequently, the bandages were changed on Days 4, 8, 11, and 15. At these time points, a filter paper imprint technique (FPIT) was made from each wound for semi-quantitative microbiological evaluation. Tissue samples from the base of the wound together with the adjacent intact tissue of three randomly selected defects of each pig were taken for microbiological, histopathological, and molecular-biological examination. The infection with the inoculated S. aureus strains was sufficient during the whole experiment as confirmed by both FPIT and from tissue samples. The dynamics of the inflammatory markers and clinical signs of infection are also described.

CONCLUSIONS

A successfully developed porcine model is suitable for in vivo testing of novel short-acting topical antimicrobial agents.

Development of a Cellular Assay as a Personalized Model for Testing Chronic Wound Therapeutics

Exudates of nonhealing wounds contain drivers of pathogenicity. We utilized >800 exudates from nonhealing and healing wounds of diverse etiologies, collected by 3 different methods, to develop a wound-specific, cell-based functional biomarker assay. Human dermal fibroblast proliferation served as readout to (i) differentiate between healing and nonhealing wounds, (ii) follow the healing process of individual patients, and (iii) assess the effects of therapeutics for chronic wounds ex vivo. We observed a strong correlation between wound chronicity and inhibitory effects of individual exudates on fibroblast proliferation, with good diagnostic sensitivity (76-90%, depending on the sample collection method). Transition of a clinically nonhealing to a healing phenotype restored fibroblast proliferation and extracellular matrix formation while reducing inflammatory cytokine production. Transcriptional analysis of fibroblasts exposed to ex vivo nonhealing wound exudates revealed an induction of inflammatory cytokine and chemokine pathways and the unfolded protein response, indicating that these changes may contribute to the pathology of nonhealing wounds. Testing the wound therapeutics, PDGF and silver sulfadiazine, yielded responses in line with clinical experience and indicates the usefulness of the assay to search for and profile new therapeutics.

Nanoengineered Self-Assembling Peptides with Increased Proteolytic Stability Promote Wound Healing

The copper complex of the tripeptide glycine-histidine-lysine (GHK) has proven benefits in wound healing and tissue remodeling by promoting blood vessel growth and increasing skin oxygen levels, but its activity is reduced in body fluids due to fast proteolytic cleavage. Herein, we designed several peptides that bear the GHK sequence and can self-assemble into supramolecular nanostructures aiming for enhanced bioactivity. The design involves a phenylalanine (F) backbone known for its ability to form supramolecular assemblies. We tested either coassembly between the structural peptide F4D and the functional sequence GHK or assembly of covalently bound peptides, in which the GHK is bound via the glycine (F4D-GHK) or lysine (F4D-KHG, i.e., inverted GHK sequence). All tested peptides assembled into nanotapes, but their resistance to proteolytic degradation was different: covalently bound peptides generated more stable assemblies. Wound healing assays demonstrated that the supramolecular structures have enhanced bioactivity when compared to GHK alone. Multiplex immunoassay analyses demonstrated the secretion of key regulators of the healing process, such as cytokines, matrix metalloproteinases, and growth factors. Altogether our data show that incorporation of GHK/KHG into supramolecular structures improves its stability, bioactivity, and efficacy in promoting wound healing.

Advancing chronic and acute wound healing with cold atmospheric plasma: cellular and molecular mechanisms, benefits, risks, and future directions

Chronic and acute wounds represent significant challenges in healthcare, often leading to prolonged recovery times and increased complications. While chronic wounds, such as diabetic foot ulcers and venous leg ulcers, persist due to underlying conditions and biofilm formation, acute wounds, including surgical incisions and burns, can also benefit from innovative therapeutic approaches. Cold atmospheric plasma (CAP) has emerged as a promising non-invasive therapy capable of enhancing wound healing outcomes across both wound types. This review examines the cellular and molecular mechanisms by which CAP promotes wound repair, focusing on its modulation of inflammation, stimulation of angiogenesis, facilitation of tissue remodeling, and antimicrobial effects, which can potentially be used in regenerative medicine. CAP generates reactive oxygen and nitrogen species that influence key cellular processes, accelerating tissue regeneration while reducing bacterial load and preventing biofilm formation. Clinical applications of CAP have demonstrated its efficacy in improving wound healing metrics for both chronic and acute wounds. Despite promising results, translating CAP into routine clinical practice requires addressing challenges such as standardizing treatment protocols, assessing long-term safety, and developing portable devices. Future research should prioritize optimizing CAP parameters and exploring combination therapies to maximize its therapeutic potential. Overall, CAP represents a safe, effective, and versatile modality in wound management, with the potential to significantly improve patient outcomes in both chronic and acute wound care.

Managing wound exudate with the superabsorbent dressing C-Sorb

Excess exudate is a major symptom of hard-to-heal wounds. It can delay wound healing and cause embarrassment and psychological distress for patients, as well as increase the number of dressing changes and thus nursing time and product costs. Exudate can be effectively managed with appropriate wound dressings, as part of a structured and holistic approach to wound assessment and care, involving treatment of the underlying aetiology. Superabsorbents are advanced, multi-layered dressings designed to absorb and retain large amounts of exudate, bacteria and matrix metalloproteinases. Different superabsorbents vary in composition and effectiveness. C-Sorb (Richardson Healthcare) is a range of superabsorbents designed to be clinically successful and cost-effective at managing moderate-to-high exudate in several types of wound. Five case studies demonstrate the positive impact of C-Sorb on exudate management and wound healing.

Chronic Wound Initiation: Single-Cell RNAseq of Cutaneous Wound Tissue and Contributions of Oxidative Stress to Initiation of Chronicity

Chronic wounds (CWs) in humans affect millions of people in the US alone, cost billions of dollars, cause much suffering, and still there are no effective treatments. Patients seek medical care when wound chronicity is already established, making it impossible to investigate factors that initiate chronicity. In this study, we used a diabetic mouse model of CWs that mimics many aspects of chronicity in humans. We performed scRNAseq to compare the cell composition and function during the first 72 h post-injury and profiled 102,737 cells into clusters of all major cell types involved in healing. We found two types of fibroblasts. Fib 1 (pro-healing) was enriched in non-CWs (NCWs) whereas Fib 2 (non-healing) was in CWs. Both showed disrupted proliferation and migration, and extracellular matrix (ECM) deposition in CWs. We identified several subtypes of keratinocytes, all of which were more abundant in NCWs, except for Channel-related keratinocytes, and showed altered migration, apoptosis, and response to oxidative stress (OS) in CWs. Vascular and lymphatic endothelial cells were both less abundant in CWs and both had impaired migration affecting the development of endothelial and lymphatic microvessels. Study of immune cells showed that neutrophils and mast cells are less abundant in CWs and that NCWs contained more proinflammatory macrophages (M1) whereas CWs were enriched in anti-inflammatory macrophages (M2). Also, several genes involved in mitochondrial function were abnormally expressed in CWs, suggesting impaired mitochondrial function and/or higher OS. Heat shock proteins needed for response to OS were downregulated in CWs, potentially leading to higher cellular damage. In conclusion, the initiation of chronicity is multifactorial and involves various cell types and cellular functions, indicating that one type of treatment will not fix all problems, unless the root cause is fundamental to the cell and molecular mechanisms of healing. We propose that such a fundamental process is high OS and its association with wound infection/biofilm.

Biological processes and factors involved in soft and hard tissue healing

Wound healing is a complex and iterative process involving myriad cellular and biologic processes that are highly regulated to allow satisfactory repair and regeneration of damaged tissues. This review is intended to be an introductory chapter in a volume focusing on the use of platelet concentrates for tissue regeneration. In order to fully appreciate the clinical utility of these preparations, a sound understanding of the processes and factors involved in soft and hard tissue healing. This encompasses an appreciation of the cellular and biological mediators of both soft and hard tissues in general as well as specific consideration of the periodontal tissues. In light of good advances in this basic knowledge, there have been improvements in clinical strategies and therapeutic management of wound repair and regeneration. The use of platelet concentrates for tissue regeneration offers one such strategy and is based on the principles of cellular and biologic principles of wound repair discussed in this review.

Bioengineered Silk Fibroin Hydrogel Reinforced with Collagen-Like Protein Chimeras for Improved Wound Healing

The study investigates the potentials of the rapid crosslinking hydrogel concoction comprising of natural silk fibroin (SF) and recombinant tailorable collagen-like protein with binding domains for wound repair. The formation of dityrosine crosslinks between the tyrosine moieties augments the formation of stable hydrogels, in the presence of the cytocompatible photo-initiator riboflavin and visible light. This uniquely engineered PASCH (Photo-activated silk fibroin and tailor-made collagen-like protein hydrogel) confers the key advantage of improved biological properties over the control hydrogels comprising only of SF. The physico-chemical characterization of the hydrogels with respect to crosslinking, modulus, and thermal stability delineates the ascendancy of PASCH 7:3 over other combinations. Furthermore, the hybrid protein hydrogel proves to be a favorable cellular matrix as it enhances cell adhesion, elongation, growth, and proliferation in vitro. Time-lapse microscopy studies reveal an enhanced wound closure in human endothelial cell monolayer (EA.hy926), while the gene expression studies portray the dynamic interplay of cytokines and growth factors in the wound milieu facilitating the repair and regeneration of cells, sculpted by the proteins. The results demonstrate the improved physical and biological properties of fabricated PASCH, depicting their synergism, and implying their competency for use in tissue engineering applications.

Potential matrix metalloproteinase 2 and 9 inhibitors identified from Ehretia species for the treatment of chronic wounds - Computational drug discovery approaches

Matrix metalloproteinases (MMPs) serve as prognostic factors in several pathophysiological conditions, including chronic wounds. Therefore, they are considered important therapeutic targets in the intervention and treatment of these conditions. In this study, computational tools such as molecular docking and molecular dynamics simulations were used to gain insight into protein‒ligand interactions and determine the free binding energy between Ehretia species phytoconstituents and gelatinases (MMP2 and MMP9). A total of 74 phytoconstituents from Ehretia species were compiled from the literature, and 46 of these compounds were identified as potential inhibitors of at least one type of MMP. Molecular docking revealed that lithospermic acid B, rosmarinic acid, and danshensu had stronger binding affinities against the two enzymes than the reference ligands. Furthermore, (9S, 10E, 12Z, 15Z)-9-hydroxy-10,12,15-octadecatrienoic (∗-octadecatrienoic) had a higher binding energy for MMP2, whereas caffeic anhydride and caffeic acid established stronger binding energy with MMP9 than the reference ligand. These complexes also demonstrated relatively stable, favourable, and comparable conformational changes with those of unbound proteins at 500 ns. The free energy decomposition results further provide detailed insights into the contributions of active site residues and different types of interactions to the overall binding free energy. Finally, most of the hit phytoconstituents (rosmarinic acid, caffeic anhydride, caffeic acid, and danshensu) had good physicochemical, drug-likeness, and pharmacokinetic properties. Collectively, our findings showed that phytoconstituents from Ehretia species could be beneficial in the search for novel MMP inhibitors as therapeutic agents for the treatment of chronic wounds.

Empirical use, phytochemical, and pharmacological effects in wound healing activities of compounds in Diospyros leaves: A review of traditional medicine for potential new plant-derived drugs

ETHNOPHARMACOLOGICAL RELEVANCE

Wound healing extracts' activity is increasingly being studied in the field of traditional medicine. Among medicinal plants, Diospyros is known to have healing effects on wounds, along with activities such as anti-biofilm, anti-inflammatory, antibacterial, antioxidant, and regulation of the immune system. However, the current use of the leaves could be more optimal, and the scientific basis needs to be improved.

AIM OF THIS REVIEW

This review aimed to critically examine the literature on the traditional use and bioactive metabolites of several Diospyros species, demonstrating the significant potential in wound healing, antibacterial, anti-biofilm, regulatory effect on the immune system, anti-inflammatory, and antioxidant activities. The critical analysis was conducted to provide robust perspectives and recommendations for future studies on the use of Diospyros potential resources of wound healing material, including related activities.

MATERIALS AND METHODS

Exploratory studies on Diospyros species over the past 20 years were examined, with a focus on general information, practical use, secondary metabolite, and pharmacological activities related to wound healing. Data were meticulously collected from scientific databases including Scopus, ScienceDirect, Web of Science, Taylor & Francis, Google Scholar, PubMed as well as various botanical and biodiversity sources. Furthermore, manual searches were conducted to ensure comprehensive coverage. Reference manager software was used to manage articles and remove duplicates, then the gathered data were summarized and verified, ensuring the thoroughness and validity of the review process.

RESULTS

The results showed that Diospyros leaves have great potential to be harnessed as herbal medications, evidenced by both scientific findings and community uses. Various substances, including flavonoids, coumarins, tannins, terpenoids, steroids, lignans, quinones, and secoiridoids were identified. Chemical compound investigations in both in vivo and in vitro studies of Diospyros leaves reported wound healing activity, as well as antibacterial, anti-inflammatory, anti-biofilm, antioxidant, and immunomodulatory properties.

CONCLUSION

The review highlights the traditional uses and bioactive metabolites of Diospyros species in wound healing, identifying various beneficial compounds such as flavonoids and tannins. These compounds demonstrate various therapeutic effects, including antibacterial, anti-biofilm, anti-inflammatory, antioxidant, and immunomodulatory activities. Diospyros leaf extracts have a favorable safety profile, but further studies, including in vivo investigations and clinical trials, are necessary to confirm their efficacy and safety for clinical applications. Diospyros leaf extracts have significant potential for the development of wound healing substances due to the wide range of bioactivities targeting various stages of wound healing.

Vitamin Bs as Potent Anticancer Agents through MMP-2/9 Regulation

In recent years, the role of coenzymes, particularly those from the vitamin B group in modulating the activity of metalloenzymes has garnered significant attention in cancer treatment strategies. Metalloenzymes play pivotal roles in various cellular processes, including DNA repair, cell signaling, and metabolism, making them promising targets for cancer therapy. This review explores the complex interplay between coenzymes, specifically vitamin Bs, and metalloenzymes in cancer pathogenesis and treatment. Vitamins are an indispensable part of daily life, essential for optimal health and well-being. Beyond their recognized roles as essential nutrients, vitamins have increasingly garnered attention for their multifaceted functions within the machinery of cellular processes. In particular, vitamin Bs have emerged as a pivotal regulator within this intricate network, exerting profound effects on the functionality of metalloenzymes. Their ability to modulate metalloenzymes involved in crucial cellular pathways implicated in cancer progression presents a compelling avenue for therapeutic intervention. Key findings indicate that vitamin Bs can influence the activity and expression of metalloenzymes, thereby affecting processes such as DNA repair and cell signaling, which are critical in cancer development and progression. Understanding the mechanisms by which these coenzymes regulate metalloenzymes holds great promise for developing novel anticancer strategies. This review summarizes current knowledge on the interactions between vitamin Bs and metalloenzymes, highlighting their potential as anticancer agents and paving the way for innovative, cell-targeted cancer treatments.

Photobiomodulation therapy in diabetes: Benefits for pain relief, quality of life, and wound healing

Globally, 537 million people suffer from diabetes mellitus (DM), a condition often associated with sensory disturbances, wound development, and chronic pain, which significantly affects the quality of life and imposes a substantial economic burden. This study evaluated the effects of photobiomodulation (PBM) therapy on nociceptive and sensory changes in diabetic patients to understand pain manifestations and explore PBM's molecular mechanisms on wound healing. Twenty patients with type 2 DM underwent clinical assessments, completed pain and quality of life questionnaires, and had their pain sensitivity evaluated using the quantitative sensory test (QST). A 5 mm skin biopsy was taken for fibroblast culture. PBM therapy, using 660 nm red light, was administered twice weekly for 7 weeks on lower limb wounds. Results indicated that DM patients faced significant sensory impairments, impacting their quality of life. PBM therapy improved pain scores, alleviated neuropathic pain, and enhanced sensory function, leading to better quality of life and reduced anxiety and depression. It also accelerated wound healing, enhancing mobility and autonomy. In vitro studies showed PBM therapy increased cell proliferation through the ERK signaling pathway and modulation of matrix metalloproteinases (MMP-1/8 and 2) and tissue inhibitors of metalloproteinases (TIMP).

Aligned membranes regulate wound healing via MMP12 secreted by macrophages

Aligned electrospinning membranes (Align) have demonstrated the potential to enhance wound healing by establishing a regenerative microenvironment surrounding the wound; However, the precise mechanism underlying its facilitation of healing remains unclear. To elucidate aligned electrospun fiber membrane's role in accelerating wound healing and improving its quality, we conducted a comprehensive analysis. Firstly, in vivo experiments confirmed that Align promotes wound healing. Through combined bulk RNA sequencing and single-cell RNA sequencing, we identified that MMP12+ macrophages exhibit high expression of MMP12 during the early stage of wound remodeling, thereby inhibiting fibroblast migration and reducing scar formation after wound closure. Finally, both in vitro and in vivo experiments further validated the role of MMP12 in promoting wound healing and suppressing fibroblast migration. Our findings reveal that Align effectively enhances skin wound healing by upregulating MMP12 expression while inhibiting fibroblast migration. These insights provide valuable knowledge on how Align promotes efficient scar-free wound healing and serve as a theoretical foundation for developing more effective biological dressings.

Wildfire-relevant woodsmoke and extracellular vesicles (EVs): Alterations in EV proteomic signatures involved in extracellular matrix degradation and tissue injury in airway organotypic models

Wildfires adversely impact air quality and public health worldwide. Exposures to wildfire smoke are linked to adverse health outcomes, including cardiopulmonary diseases. Critical research gaps remain surrounding the underlying biological pathways leading to wildfire-induced health effects. The regulation of intercellular communication and downstream toxicity driven by extracellular vesicles (EVs) is an important, understudied biological mechanism. This study investigated EVs following a wildfire smoke-relevant in vitro exposure. We hypothesized that woodsmoke (WS) would alter the proteomic content of EVs secreted in organotypic in vitro airway models. Exposures were carried out using a tri-culture model of alveolar epithelial cells, fibroblasts, and endothelial cells and a simplified co-culture model of alveolar epithelial cells and fibroblasts to inform responses across different cell populations. Epithelial cells were exposed to WS condensate and EVs were isolated from basolateral conditioned medium following 24 h exposure. WS exposure did not influence EV particle characteristics, and it moderately increased EV count. Exposure caused the differential loading of 25 and 35 proteins within EVs collected from the tri- and co-culture model, respectively. EV proteins involved in extracellular matrix degradation and wound healing were consistently modulated across both models. However, distinct proteins involved in the wound healing pathway were altered between models, suggesting unique but concerted efforts across cell types to communicate in response to injury. These findings demonstrate that a wildfire-relevant exposure alters the EV proteome and suggest an impact on EV-mediated intercellular communication. Overall, results demonstrate the viability of organotypic approaches in evaluating EVs to investigate exposure-induced biomarkers and underlying mechanisms. Findings also highlight the impact of differences in the biological complexity of in vitro models used to evaluate the effects of inhaled toxicants.

Naturally Inspired Tree-Ring Structured Dressing Provides Sustained Wound Tightening and Accelerates Closure

Mechanically regulated wound dressings require a rational combination of contraction and adhesion functions as well as balancing exudate-induced swelling issues. However, many of the reported dressings face the dilemma of impaired function and impeded wound self-contraction due to fluid-absorbing swelling. In this study, inspired by the tree ring, a core-ring structured hydrogel dressing capable of mechanical modulation is designed, and prepare it using a simple two-step photopolymerization process. The core covers the center of the wound, contracts spontaneously at body temperature to generate a contractile force of 3.4 kPa, and resists swelling. Meanwhile, the ring adheres to the normal epidermis around the wound and transfers the contraction stress to the wound edge. The integration of a functionally independent core and ring ultimately achieves effective wound traction and avoids dressing swelling. In murine and porcine skin wound-healing models, this hydrogel with a closely connected core and ring promotes healing by accelerating epidermal closure (50% closure in mouse skin on day 2, 85% closure in pig skin on day 8), collagen deposition, vascular maturation, and extracellular matrix remodeling. These results can guide further research on mechanical force modulation in wound healing, with the potential for clinical translation.

Recent advancements in drug delivery system of flavonoids with a special emphasis on the flavanone naringenin: exploring their application in wound healing and associated processes

Numerous flavonoids have been identified in citrus fruits which show potential to cure several complex diseases. These natural polyphenolic bioactive compounds are the secondary metabolites of various plants, among which naringenin has been explored in several pre-clinical research for its beneficial role in promoting health by modulating various biochemical processes. Its antioxidant, anti-inflammatory, and anti-microbial effects have been projected toward healing of wounds. Further, its application has also been shown to regrow vascular networks, which are known to facilitate the healing of chronic wounds. Thus, the potential of naringenin to modulate various molecular pathways aids in the healing process of wounds. Considering the recent literature, an update has been attempted to present the correlation between the healing mechanisms of wounds by the application of naringenin. Furthermore, the application of naringenin is challenging because of its properties of poor solubility and limited permeability, which can be overcome by the nanotechnology platform. Thus, several nanocarriers that have been employed for the improvement of naringenin delivery are highlighted. Thereby, it can be concluded that a suitable nanocarrier of naringenin could be an effective tool in treating wounds to improve the quality of life of such patients.

Role of MMP inhibitors on levels of MMP-2 and MMP-9 in mammalian cell lines - A systematic review

Matrix metalloproteinases (MMPs) are proteolytic enzymes involved in extracellular matrix (ECM) degradation, contributing to various pathological conditions, including periapical lesions and periodontal diseases. This systematic review evaluates the inhibitory effects of different natural and synthetic MMP inhibitors on MMP-2 and MMP-9 activities in mammalian cells, which are critical enzymes implicated in ECM breakdown. A comprehensive literature search was performed across databases, including PubMed, Scopus, and Cochrane until June 2023, following PRISMA guidelines. The Office of Health Assessment and Translation (OHAT) risk of bias tool was used for quality assessment, revealing a low risk of bias across all studies. Our findings demonstrate that both natural and synthetic MMP inhibitors significantly reduce MMP-2 and MMP-9 activities in mammalian cells. These compounds offer potential therapeutic benefits in managing diseases characterized by excessive MMP activity, such as periapical lesions and periodontal disease. This review highlights the therapeutic potential of MMP inhibitors in dentistry, specifically focusing on the promising roles of natural and synthetic MMP inhibitors in protecting ECM integrity.

Lilium candidum Extract Loaded in Alginate Hydrogel Beads for Chronic Wound Healing

Chronic wounds are a major health problem, affecting millions of people worldwide. Resistance to treatment is frequently observed, requiring an extension of the wound healing time, and improper care can lead to more problems in patients. Smart wound dressings that provide a controlled drug release can significantly improve the healing process. In this paper, alginate beads with white lily leaf extract were prepared and tested for chronic wound healing. The obtained beads were characterized by scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). Also, the efficiency of extract encapsulation in alginate was determined as being of. The obtained hydrogel was tested on two normal human cell lines, respectively, dermal fibroblasts (BJ-CRL-2522-ATCC) and endothelial cells (human umbilical vein endothelial cells-HUVEC 2). The longer release of bioactive compounds from plant extract loaded in the alginate hydrogel resulted in more effective wound closure, compared to the extract alone, and scar formation, compared to the alginate hydrogel. Therefore, the effect of the white lily extract in combination with that of sodium alginate hydrogel improves the biological activity of the alginate hydrogel and increases the wound healing properties of the alginate.

Thyroid hormone receptor- and stage-dependent transcriptome changes affect the initial period of Xenopus tropicalis tail regeneration

BACKGROUND

Thyroid hormone (T3) has an inhibitory effect on tissue/organ regeneration. It is still elusive how T3 regulates this process. It is well established that the developmental effects of T3 are primarily mediated through transcriptional regulation by thyroid hormone receptors (TRs). Here we have taken advantage of mutant tadpoles lacking both TRα and TRβ (TRDKO), the only receptor genes in vertebrates, for RNA-seq analyses to investigate the transcriptome changes underlying the initiation of tail regeneration, i.e., wound healing and blastema formation, because this crucial initial step determines the extent of the functional regeneration in the later phase of tissue regrowth.

RESULTS

We discovered that GO (gene ontology) terms related to inflammatory response, metabolic process, cell apoptosis, and epithelial cell migration were highly enriched among commonly regulated genes during wound healing at either stage 56 or 61 or with either wild type (WT) or TRDKO tadpoles, consistent with the morphological changes associated with wound healing occurring in both regenerative (WT stage 56, TRDKO stage 56, TRDKO stage 61) and nonregenerative (WT stage 61) animals. Interestingly, ECM-receptor interaction and cytokine-cytokine receptor interaction, which are essential for blastema formation and regeneration, were significantly enriched among regulated genes in the 3 regenerative groups but not the non-regenerative group at the blastema formation period. In addition, the regulated genes specific to the nonregenerative group were highly enriched with genes involved in cellular senescence. Finally, T3 treatment at stage 56, while not inducing any measurable tail resorption, inhibited tail regeneration in the wild type but not TRDKO tadpoles.

CONCLUSIONS

Our study suggests that TR-mediated, T3-induced gene regulation changed the permissive environment during the initial period of regeneration and affected the subsequent patterning/outgrowth period of the regeneration process. Specifically, T3 signaling via TRs inhibits the expression of ECM-related genes while promoting the expression of inflammation-related genes during the blastema formation period. Interestingly, our findings indicate that amputation-induced changes in DNA replication-related pathways can occur during this nonregenerative period. Further studies, particularly on the regenerative microenvironment that may depend on ECM-receptor interaction and cytokine-cytokine receptor interaction, should provide important insights on the regulation of regenerative capacity during vertebrate development.

Evaluating antibacterial and antioxidant properties of sericin recovered from cocoons of Bombyx mori, Gonometa postica and Samia ricini in Kenya

Microbial infections and excessive reactive oxygen species are the primary contributors to delays in wound healing with Pseudomonas aeruginosa, Escherichia coli and Staphylococcus aureus as the common wound infection causing bacteria. In fact, wound management has become more challenging since most of these microbes have developed resistance against commonly used conventional antibiotics thus making it necessary to develop natural products with both antibacterial and antioxidant activities. Increasing attention has been paid to silk sericin in the last decade, with limited research focus in Africa. Therefore, this work focus on evaluating antibacterial and antioxidant capacity of sericin recovered from cocoons of domesticated (Bombyx mori, Samia ricini) and wild (Gonometa postica) silkworms in Kenya. Sericin recovery was achieved using high temperature-high pressure method. Results revealed significance interspecies variation in all the parameters. Total flavonoid content ranged between 270±60.1 and 603.3±44.1 mg GAE/100g with S. ricini demonstrating the highest whereas G. postica exhibited the least content. Moreover, S. ricini showed the highest total phenolic content at 780.0±67.6 mg QE/100g while G. postica had the least phenolic content at 330.6±14.6 mg QE/100g. Samia ricini revealed the highest radical scavenging capacity at 40.47 ± 3.76% whereas B. mori sericin extract showed the least radical scavenging ability at 24.6± 2.96%. Furthermore, S. ricini silk sericin extract demonstrated the highest inhibitory activity against Staphylococcus aureus, Pseudomonas aeruginosa and Klebsiella pneumonia which translated to 70.79 ± 11.28%, 93.86 ± 1.92%, 94.77 ± 7.07% when compared to streptomycin, chloramphenicol and oxytetracycline respectively. Bombyx mori and Gonometa postica showed the highest inhibitory activity against S. pyogene and E. coli respectively. These findings uncovered sufficient antibacterial efficacy of all three silk sericin extracts against both Gram-positive and negative bacteria, however, in depth research is still required to guarantee the aforementioned bioactivities to boost the therapeutic potential of silk sericin-based biomaterials.

Reprogramming of epidermal keratinocytes by PITX1 transforms the cutaneous cellular landscape and promotes wound healing

Cutaneous wound healing is a slow process that often terminates with permanent scarring while oral wounds, in contrast, regenerate after damage faster. Unique molecular networks in epidermal and oral epithelial keratinocytes contribute to the tissue-specific response to wounding, but key factors that establish those networks and how the keratinocytes interact with their cellular environment remain to be elucidated. The transcription factor PITX1 is highly expressed in the oral epithelium but is undetectable in cutaneous keratinocytes. To delineate if PITX1 contributes to oral keratinocyte identity, cell-cell interactions, and the improved wound healing capabilities, we ectopically expressed PITX1 in the epidermis of murine skin. Using comparative analysis of murine skin and oral (buccal) mucosa with single-cell RNA-Seq and spatial transcriptomics, we found that PITX1 expression enhances epidermal keratinocyte migration and proliferation and alters differentiation to a quasi-oral keratinocyte state. PITX1+ keratinocytes reprogrammed intercellular communication between skin-resident cells to mirror buccal tissue while stimulating the influx of neutrophils that establish a pro-inflammatory environment. Furthermore, PITX1+ skin healed significantly faster than control skin via increased keratinocyte activation and migration and a tunable inflammatory environment. These results illustrate that PITX1 programs oral keratinocyte identity and cellular interactions while revealing critical downstream networks that promote wound closure.

Efficacy of neutral electrolyzed water vs. common topical antiseptics in the healing of full‑thickness burn: Preclinical trial in a mouse model

Burn injuries impose challenges such as infection risk, pain management, fluid loss, electrolyte imbalance and psychological and emotional impact, on healthcare professionals, requiring effective treatments to enhance wound healing. The present study evaluated the efficacy superoxidized electrolyzed solution (SES), with low (SES-low) or high (SES-high) concentrations of active species, alone or in combination with a formulation in gel (G), in comparison with commonly prescribed treatments for burn injury, including nitrofurazone (NF) and silver sulfadiazine (S); normal saline was used as placebo (PI). A scald burn model was established in BALB/c mice. Measurements of the burned area and histological parameters such as inflammatory infiltration state, epithelial regeneration and collagen fibers were evaluated on days 3, 6, 9, 18 and 32 to assess healing score and status. All treatments achieved wound closure at day 32; histopathological parameters indicated that SES-low and SES-low + G performed better than the Pl and S groups (P<0.05). All treatments showed a lower count of inflammatory cells compared with S (P<0.05); for collagen deposition and orientation, SES-low + G showed a more uniform horizontal orientation compared with Pl, SES-high + G, NF and S groups (P<0.05). SES-Low was the most effective substance to induce favorable and organized healing, while S was the worst, inducing disorganized closure of the wound due to a pro-inflammatory effect.

Matrix Metalloproteinases on Skin Photoaging

BACKGROUND

Skin aging is characterized by an imbalance between the generation and degradation of extracellular matrix molecules (ECM). Matrix metalloproteinases (MMPs) are the primary enzymes responsible for ECM breakdown. Intrinsic and extrinsic stimuli can induce different MMPs. However, there is limited literature especially on the summary of skin MMPs and potential inhibitors.

OBJECTIVE

We aim to focus on the upregulation of MMP expression or activity in skin cells following exposure to UV radiation. We also would like to offer valuable insights into potential clinical applications of MMP inhibitors for mitigating skin aging.

METHODS

This article presents the summary of prior research, which involved an extensive literature search across diverse academic databases including Web of Science and PubMed.

RESULTS

Our findings offer a comprehensive insight into the effects of MMPs on skin aging after UV irradiation, including their substrate preferences and distinct roles in this process. Additionally, a comprehensive list of natural plant and animal extracts, proteins, polypeptides, amino acids, as well as natural and synthetic compounds that serve as inhibitors for MMPs is compiled.

CONCLUSION

Skin aging is a complex process influenced by environmental factors and MMPs. Research focuses on UV-induced skin damage and the formation of Advanced Glycosylation End Products (AGEs), leading to wrinkles and impaired functionality. Inhibiting MMPs is crucial for maintaining youthful skin. Natural sources of MMP inhibitor substances, such as extracts from plants and animals, offer a safer approach to obtain inhibitors through dietary supplements. Studying isolated active ingredients can contribute to developing targeted MMP inhibitors.

Exploring the wound-healing potential and seasonal chemical variability of the Formosan Callery pear Pyrus calleryana: implications for therapeutic applications

CONTEXT

Pyrus calleryana Decne (Rosaceae), renowned for its therapeutic properties, is known to moisturize the lungs (removing dryness; relieving cough), clear heat (acting as an antipyretic; febrifuge) and aid in detoxification (relieving pyogenic inflammation; eliminating toxins). However, scientific evidence supporting its efficacy in wound healing is lacking.

OBJECTIVE

This study investigated P. calleryana samples collected over a year to explore metabolite variations and their impact on skin wound-healing activities.

MATERIALS AND METHODS

P. calleryana (PC) twigs and leaves were collected from the Matsu Islands, Taiwan, spanning 2018-2020. Extracts were prepared using 95% ethanol or water, and we assessed the chemical composition, total phenolic/triterpenoid contents and antioxidant properties. Metabolites were analysed via LC-MS/MS and molecular networking. Wound healing potential was evaluated on WS-1 cells through MTT and migration assays, and gene expression analyses, with tests including control (DMSO), compounds 1 (3'-hydroxylbenzyl-4-hydroxybenzoate-4'-O-β-glucopyranoside) and 2 (vanilloylcalleryanin) (100 µM), and a positive control (ascorbic acid, 100 µM) for 24 h.

RESULTS

Significant variations in extract compositions were observed based on the solvent used, with distinct metabolomic profiles in extracts collected during different months. Notably, compounds 1 and 2 showed no cytotoxic effects on human dermal fibroblast cells and significantly accelerated wound closure at 100 μM. A gene expression analysis indicated upregulation of wound healing-associated genes, including MMP-1 (matrix metalloproteinase-1) and COL1A1 (collagen, type 1, alpha 1).

CONCLUSIONS

This study reports the first evidence of PC compounds aiding wound healing. Utilizing Global Natural Products Social Molecular Networking (GNPS) and principal component analysis (PCA) approaches, we unveiled metabolomic profiles, suggesting the potential to expedite wound-healing.

Human Keratin Matrices Suppress Matrix Metalloproteinase Activity to Support Wound Healing

Elevated protease activity is a hallmark of non-healing chronic wounds. Though multiple biomaterials exist that are successful in treating wounds, their roles in modulating the enzymatic environment of the wound are only beginning to be elucidated. Because keratin has long been known to be resistant to degradation by most enzymes, we studied a keratin biomaterial, the human keratin matrix (HKM), in the presence of enzymes identified to contribute to wound chronicity: neutrophil-derived elastase (NE), matrix metalloproteinase 1 (MMP-1), and MMP-9. Upon finding the suppression of MMP-9 activity in the presence of HKM without reducing enzyme protein levels, we further studied the ability of HKM to bind metal ions in the wound and showed the reduction of Zn2+ ion concentration in the presence of HKM. Finally, because of the enzyme resistance of keratin and the suppression of wound enzymes, we demonstrated that HKM was durable in the wound environment, and did not degrade in wound healing efficacy when left in place for two weeks compared to one week in a diabetic mouse model of wound non-healing. In this way, we show HKM is a unique and effective biomaterial for the treatment of chronic wounds through the modulation of wound MMP activity.

Optimising outcomes with 'Wound Balance' and dressings containing superabsorbent polyacrylate polymers

The ever-increasing burden of hard-to-heal wounds requires emphasis placed on early intervention to help heal wounds and improve patient quality of life. A patient's healing potential can be optimised by applying the 'Wound Balance' holistic framework for wound assessment, care planning and quality of life considerations. This holistic management can be facilitated with appropriate dressings, such as dressings containing superabsorbent polyacrylate polymers (SAPs), including RespoSorb® Silicone Border (Hartmann). SAP-containing dressings can absorb exudate and bind and lock away wound inhibitors, such as proteases and micro-organisms, reversing the factors associated with hard-to-heal wounds to enable a healing environment similar to an acute wound. Three case studies demonstrate the positive benefits of using RespoSorb Silicone Border in clinical practice. The dressings proved easy to use and comfortable, with atraumatic changes and long wear times, providing a costeffective option for patients with both acute and hard-to-heal wounds.