Signaling pathways in cutaneous wound healing

Zinc-doped curcumin carbon dots promote infected wound healing with photodynamic via the VEGF signaling pathway

Management of bacterial infected wounds remains challenging due to the open, susceptibility to infection and delayed healing characteristics of damaged wounds, and there is an urgent need for non-antibiotic-based wound healing strategies. Here, we describe zinc-doped curcumin carbon dots (CCDs) as a novel nanoscale photosensitizer, which was applied in photodynamic therapy (PDT) to promote infected wound healing by modulating various cellular functions. The PDT generation of reactive oxygen species (ROS) effectively inactivates the source of infection without drug resistance, effectively inhibiting the propagation of bacteria and the spread of inflammation in the wound. In addition, CCDs have the ability to promote cell proliferation and extension, accelerate blood vessel formation and collagen deposition, and significantly improve wound healing efficiency by modulating the VEGF signaling pathway. These features create a favorable environment for skin regeneration and synergistically accelerate infected wound healing. We believe it has great potential to address antibiotic misuse and effectively manage infected wounds.

High-dimensional signalling analysis of organoids

Cellular phenotypes are regulated by dynamic signalling processes that involve proteins, post-translational modifications, epigenetic events, and transcriptional responses. Functional perturbation studies are required to understand cell signalling mechanisms and organoids have recently emerged as scalable biomimetic models amenable to large-scale perturbation. Here, we review the recent advances in high-dimensional analysis of cell signalling in organoids. Single-cell technologies provide cell-type specific analysis of multiple biochemical modalities, enabling a deeper understanding of the signalling mechanisms driving cell-fate dynamics. Emerging multimodal techniques are further revealing coordination between signalling layers and are poised to increase our mechanistic understanding of cell signalling.

Identification of TRPV1-Inhibitory Peptides from Takifugu fasciatus Skin Hydrolysate and Their Skin-Soothing Mechanisms

Skin sensitivity is increasingly prevalent, necessitating new therapeutic agents. This study screened multifunctional peptides from Takifugu fasciatus skin for transient receptor potential vanilloid 1 (TRPV1)-inhibitory and anti-inflammatory activities and investigated their mechanisms in alleviating sensitive skin (SS). A low-molecular-weight hydrolysate was prepared through enzymatic hydrolysis of T. fasciatus skin, followed by ultrafiltration, with subsequent peptide identification performed using nano-HPLC-MS/MS and molecular docking-based virtual screening. Among 20 TRPV1-antagonistic peptides (TFTIPs), QFF (T10), LDIF (T14), and FFR (T18) exhibited potent anti-inflammatory effects in (lipopolysaccharide) LPS-induced RAW 264.7 macrophages. T14 showed the strongest TRPV1 inhibition; T14 (200 μM) inhibited Ca2⁺ in capsaicin-stimulated HaCaT cells by 73.1% and showed stable binding in molecular docking, warranting further analysis. Mechanistic studies revealed that T14 suppressed NF-κB signaling by downregulating p65 protein expression, thereby reducing pro-inflammatory cytokine secretion (G-CSF, GM-CSF, ICAM-1, IL-6, TNF-α) in RAW 264.7 cells. Additionally, T14 (400 μM) inhibited ET-1 in LPS-stimulated endothelial cells by 75.0%; ICAM-1 reached 49.0%. Network pharmacology predicted STAT3, MAPK3, SPHK1, and CTSB as key targets mediating T14's effects. These study findings suggest that T14 may be a promising candidate for skincare applications targeting SS.

Cold Atmospheric Plasma Jet Promotes Wound Healing Through CK2-Coordinated PI3K/AKT and MAPK Signaling Pathways

The promising role of cold atmospheric plasma jet (CAPJ) treatment in promoting wound healing has been widely documented in therapeutic implications. However, the fact that not all subjects respond equally to CAPJ necessitates the investigation of the underlying cellular mechanisms, which have been rarely understood so far. Given that wound healing is a complex and prolonged process, post plasma-activated medium (PAM) treated keratinocytes were collected at two time points, 2 h (receiving) and 24 h (recovery), for (phospho)proteomic analysis to systematically dissect the molecular basis of CAPJ-promoted wound healing. The receiving (phospho)proteomics datasets, referred to the time point of 2 h, revealed an apparent increase in the phosphorylation of CK2 and its-mediated PI3K/AKT and MAPK signaling pathways, accompanied by a prompted downstream physiological response of cell migration. Additionally, incorporating the network analysis of predicted kinases and their direct interactors, we reiterated that CAPJ influenced cell growth and migration, thereby paving the way for its role in subsequent wound healing processes. Further determining the proteome profiles at recovery phase, which is the time point of 24 h, displayed a totally different view from the receiving proteome which had almost no change. The upregulation of ROBOs/SLITs expression and vesicle trafficking and fusion-related proteins, along with the abundant presence of 14-3-3 family proteins, indicated that the persistent effect of PAM on the wound healing process could potentially promote keratinocyte-fibroblast cross talk and stimulate extracellular matrix synthesis upon epithelialization. Consistent with proteome patterns, CAPJ-treated wound tissues indeed showed a denser and well-organized extracellular matrix architecture, implying hastened epithelialization during wound healing. Collectively, we delineated the molecular basis of CAPJ-accelerated wound healing at early and late responses, providing valuable insights for treatment selection and the development of therapeutic strategies to achieve better outcomes.

Elevating Dermatology Beyond Aesthetics: Perinatal-Derived Advancements for Rejuvenation, Alopecia Strategies, Scar Therapies, and Progressive Wound Healing

Dermatologists have been interested in recent advancements in regenerative therapy. Current research is actively investigating the possibility of placental tissue derivatives to decelerate the skin aging process, enhance skin regeneration, reduce scarring, and prevent hair loss. Amniotic membranes (AM) play a crucial role in regenerative medicine as they serve as a suitable means of transporting stem cells, growth hormones, cytokines, and other essential compounds. Regulating an intricate network of biological processes improves the development and repair of tissues. Studies done by dermatologists indicate that several compounds found in the decidua, umbilical cord, and amniotic membrane have the potential to be used for regeneration. Examples include mesenchymal stem cells, growth factors, and immunomodulatory pharmaceuticals. Due to research and technological developments, scientists may use placental sections to facilitate skin regeneration, minimize scarring, and expedite wound healing. This study examines the current state of dermatological therapy, with a focus on using derivatives obtained from fetal tissue as the basis. The critical areas of study focus on this strategy are the potential benefits, growth opportunities, and recovery rates. Based on a thorough examination of the available literature and clinical data, we want to make definitive conclusions on the possible influence of fetal tissue derivatives in dermatological therapy.

Hybrid thermosensitive hydrogel/amniotic membrane structure incorporating S-nitrosothiol microparticles: potential uses for controlled nitric oxide delivery

Insufficient levels of nitric oxide may lead to chronic and acute wounds. Additionally, it is crucial that nitric oxide is prepared in a controlled-release manner due to its gaseous nature and short half-life. To address this issue, utilizing nitric oxide donors, particularly S-nitrosothiols such as S-nitrosoglutathione (GSNO), could efficiently overcome instability and aid in biomedical applications. Decellularized human amniotic membranes are also best known for their anti-inflammatory, angiogenic, and antimicrobial properties to promote wound epithelization. In this study, a novel nitric oxide-generated wound dressing based on an amniotic membrane was investigated. This construct consisted of a chitosan/β-glycerophosphate thermosensitive hydrogel covered with a decellularized human amniotic layer embedded with GSNO-loaded polylactic acid microparticles. The structure of GSNO was confirmed by spectrometric, elemental, and chemical analyses. The GSNO-loaded microparticles had a diameter of 40.66 ± 6.92 µm, and an encapsulation efficiency of 45.6 ± 6.74%. The hybrid construct and GSNO-loaded microparticles enhanced the long-term stable release of GSNO compared to free GSNO. The construct released nitric oxide ranging from 24 to 68 nM/mg during 7 days. The thermosensitive hydrogel was formed at 32.7 ± 1 °C and had a porous structure with a pore size of 41.76 ± 9.76 µm. The MTT and live/dead assays performed on human dermal fibroblast cells demonstrated suitable cell viability and adhesion to the final construct. Further, hemolysis analysis revealed less than a 5% hemolysis rate due to negligible blood cell adhesion. Overall, the prepared hybrid construct demonstrated suitable characteristics as a potential active wound dressing capable of controlled nitric oxide delivery.

In silico Profiling and Pharmacokinetic Modelling of Olivetol: Evaluating its Potential as a Therapeutic Agent for Diabetic Wound Healing

BACKGROUND

Diabetic wound healing poses a significant challenge due to the intricate disruptions in cellular and molecular processes induced by hyperglycaemia, leading to delayed or impaired tissue repair. Computational techniques offer a promising avenue for unravelling the complexities of diabetic wound healing by elucidating the molecular mechanisms involved.

METHODOLOGY

This study utilized in silico molecular docking and dynamics simulations to explore the potential therapeutic effectiveness of olivetol, a phenolic compound, in the context of diabetic wound healing. Furthermore, computational methodologies, encompassing pkCSM, Swiss ADME, OSIRIS® property explorer, PASS online web resource, and MOLINSPIRATION® software, were employed to forecast the pharmacokinetic properties, biological actions, and in vitro analyses, such as MTT and scratch assays, to evaluate the therapeutic effectiveness of olivetol in wound healing.

RESULTS AND DISCUSSION

Our findings have revealed olivetol to be a promising candidate for targeting multiple pathways implicated in diabetic wound healing. Its ability to modulate inflammation, oxidative stress, extracellular matrix remodeling, angiogenesis, and cell signaling suggests a multifaceted approach to promoting effective wound repair. Moreover, olivetol has been found to demonstrate strong binding affinity with key MRSA target proteins, indicating its potential as an antimicrobial agent against MRSA infections in diabetic wounds. The in vitro MTT assay demonstrated cell viability with an IC50 value of 40.80 μM, highlighting its cytotoxicity potential. Additionally, the scratch assay confirmed promising wound healing activity, showcasing its effectiveness in promoting cell migration and closure.

CONCLUSION

Olivetol emerges as a promising candidate for targeted interventions in non-healing diabetic wounds, particularly due to its ability to address prolonged inflammation, a common obstacle in diabetic wound healing.

The role of neuropeptides in cutaneous wound healing: a focus on mechanisms and neuropeptide-derived treatments

An extensive network of cutaneous nerves, neuropeptides, and specific receptors richly innervates the skin and influences a variety of physiological and pathological processes. The sensory and autonomic nerve fibers secrete a variety of neuropeptides that are essential to the different phases of wound healing. In addition to initiating a neurogenic inflammatory response in the early stages of healing, neuropeptides also control wound healing by influencing immune cells, repair cells, and the growth factor network. However, the precise mechanism by which they accomplish these roles in the context of cutaneous wound healing is still unknown. Investigating the mechanisms of action of neuropeptides in wound healing and potential therapeutic applications is therefore urgently necessary. The present review discusses the process of wound healing, types of neuropeptides, potential mechanisms underlying the role of neuropeptides in cutaneous wound healing, as well as some neuropeptide-derived treatment strategies, such as hydrogels, new dressings, electro stimulation, and skin-derived precursors. Future in-depth mechanistic studies of neuropeptides in cutaneous wound healing may provide opportunities to develop therapeutic technologies that harness the roles of neuropeptides in the wound healing process.

Epidermal Growth Factor Intralesional Delivery in Chronic Wounds: The Pioneer and Standalone Technique for Reversing Wound Chronicity and Promoting Sustainable Healing

The early expectations about growth factors' (GFs') discovery as an undisputed therapeutic solution for chronic wounds progressively eclipsed when they failed to accelerate acute wound closure and restore the healing trajectory of stagnant ulcers. Critical knowledge about chronic wound biology and GF pharmacology was a conundrum at that time. Diabetes undermines keratinocytes' and fibroblasts' physiology, impairing skin healing abilities. Diabetic ulcers, as other chronic wounds, are characterized by hyperinflammation, unbalanced proteolytic activity, catabolism, and free radical cytotoxicity. This hostile scenario for the chemical stability, integrity, and functionality of GFs led to the conclusion that topical administration may jeopardize GFs' clinical effectiveness. Epidermal growth factor (EGF) has a proximal position in tissues homeostasis by activating survival and mitogenic pathways from embryonic life to adulthood. Seminal experiments disclosed unprecedented pharmacological bounties of parenterally administered EGF. Accordingly, the experience accumulated for more than 20 years of EGF intralesional infiltration of diabetic wound bottoms and edges has translated into sustained healing responses, such as low recurrences and amputation rates. This delivery route, in addition to being safe and tolerated, has shown to restore a variety of circulating biochemical markers ordinarily disturbed in diabetic conditions. EGF infiltration triggers a cascade of local fibroblast reactions, supporting its molecular integrity, prolonged mean residence time, and ultimately eliciting its receptor trafficking and nuclear translocation. The intralesional delivery route seems to warrant that EGF reaches wound fibroblasts' epigenetic core, mitigating the consequences of metabolic memory imprinting.

Diverse calcium signaling profiles regulate migratory behavior in avascular wound healing and aberrant signal hierarchy occurs early in diabetes

In avascular wound repair, calcium signaling events are the predominant mechanism cells use to transduce information about stressors in the environment into an effective and coordinated migratory response. Live cell imaging and computational analysis of corneal epithelial wound healing revealed that signal initiation and propagation at the wound edge are highly ordered, with groups of cells engaging in cyclical patterns of initiation and propagation. The cells in these groups exhibit a diverse range of signaling behavior, and dominant "conductor cells" drive activity in groups of lower-signaling neighbors. Ex vivo model systems reveal that conductor cells are present in wing cell layers of the corneal epithelium and that signaling propagates both within and between wing and basal layers. There are significant aberrations in conductor phenotype and interlayer propagation in type II diabetic murine models, indicating that signal hierarchy breakdown is an early indicator of disease. In vitro models reveal that signaling profile diversity and conductor cell phenotype is eliminated with P2X7 inhibition and is altered in Pannexin-1 or P2Y2 but not Connexin-43 inhibition. Conductor cells express significantly less P2X7 than their lower-signaling neighbors and exhibit significantly less migratory behavior after injury. Together, our results show that the postinjury calcium signaling cascade exhibits significantly more ordered and hierarchical behavior than previously thought, that proteins previously shown to be essential for regulating motility are also essential for determining signaling phenotype, and that loss of signal hierarchy integrity is an early indicator of disease state. NEW & NOTEWORTHY Calcium signaling in corneal epithelial cells after injury is highly ordered, with groups of cells engaged in cyclical patterns of event initiation and propagation driven by high-signaling cells. Signaling behavior is determined by P2X7, Pannexin-1, and P2Y2 and influences migratory behavior. Signal hierarchy is observed in healthy ex vivo models after injury and becomes aberrant in diabetes. This represents a paradigm shift, as signaling was thought to be random and determined by factors in the environment.

Fabrication of fiber-particle structures by electrospinning/electrospray combination as an intrinsic antioxidant and oxygen-releasing wound dressing

In this study, we employed a combination of electrospinning and electrospray techniques to fabricate wound dressings with a particle-fiber structure, providing dual characteristics of oxygen-releasing and intrinsic antioxidant properties, simultaneously. The electrospun part of the dressing was prepared from a blend of polycaprolactone/gallic acid-grafted-gelatin (GA-g-GE), enabling intrinsic ROS scavenging. To the best of our knowledge, this is the first time that PCL/GA-g-GE was fabricated by electrospinning. Furthermore, polyvinyl pyrrolidone (PVP) microparticles, containing calcium peroxide nanoparticles (CNPs), were considered as the oxygen production agent through the electrospray part. The CNP content was 1% and 3% w/w of PVP while biopolymer:PCL was 10% w/w. The fabricated structures were characterized in terms of fiber/particle morphology, elemental analysis, oxygen release behavior, ROS inhibition capacity, and water contact angle assessments. The covalent bonding of gallic acid to gelatin was confirmed by 1H-NMR, UV spectroscopy, and FTIR. According to the SEM results, the morphology of the prepared PCL/biopolymer fibers was bead-free and with a uniform average diameter. The analysis of released oxygen showed that by increasing the weight percentage of CNPs from 1 to 3 wt%, the amount of released oxygen increased from 120 mmHg to 195 mmHg in 24 h, which remained almost constant until 72 h. The obtained DPPH assay results revealed that the introduction of GA-g-GE into the fibrous structure could significantly improve the antioxidant properties of wound dressing compared to the control group without CNPs and modified gelatine. In vitro, the fabricated wound dressings were evaluated in terms of biocompatibility and the potential of the dressing to protect human dermal fibroblasts under oxidative stress and hypoxia conditions by an MTT assay. The presence of GA-g-GE led to remarkable protection of the cells against oxidative stress and hypoxia conditions. In vivo studies revealed that the incorporation of intrinsic ROS inhibition and oxygen-releasing properties could significantly accelerate the wound closure rate during the experimental period (7, 14, and 21 days). Additionally, histopathological investigations in terms of H&E and Masson's trichrome staining showed that the incorporation of the two mentioned capabilities remarkably facilitated the wound-healing process.

Co-Expression Network and Machine Learning Analysis of Transcriptomics Data Identifies Distinct Gene Signatures and Pathways in Lesional and Non-Lesional Atopic Dermatitis

BACKGROUND

Atopic dermatitis (AD) is a common inflammatory skin condition with complex origins. Current treatments often yield suboptimal results due to an incomplete understanding of its underlying mechanisms. This study aimed to identify pathway and gene signatures that distinguish between lesional AD, non-lesional AD, and healthy skin.

METHOD

We conducted differential gene expression and co-expression network analyses to identify differentially co-expressed genes (DCEGs) in lesional AD vs. healthy skin, lesional vs. non-lesional AD, and non-lesional AD vs. healthy skin. Modules associated with lesional and non-lesional AD were identified based on the correlation coefficients between module eigengenes and clinical phenotypes (|R| ≥ 0.5, p-value < 0.05). Subsequently, we employed Ingenuity Pathway Analysis (IPA) on the identified DCEGs, followed by machine learning (ML) analysis within the pathway expression framework. The ML analysis of pathway expressions, selected by IPA and derived from gene expression data, identified relevant pathway signatures, which were validated using an independent dataset and correlated with AD severity measures (EASI and SCORAD).

RESULTS

We identified 975, 441, and 40 DCEGs in lesional vs. healthy skin, lesional vs. non-lesional, and non-lesional vs. healthy skin, respectively. IPA and ML analyses revealed 25 relevant pathway signatures, including wound healing, glucocorticoid receptor signaling, and S100 gene family signaling pathways. Validation confirmed the significance of 10 pathway signatures, which were correlated with the AD severity measures. DCEGs such as MMP12 and S100A8 demonstrated high diagnostic efficacy (AUC > 0.70) in both the discovery and validation datasets.

CONCLUSIONS

Differential gene expression, co-expression networks and ML analyses of pathway expression have unveiled relevant pathways and gene signatures that distinguish between lesional, non-lesional, and healthy skin, providing valuable insights into AD pathogenesis.

Quaternized oxidized sodium alginate injectable hydrogel with high antimicrobial and hemostatic efficacy promotes diabetic wound healing

In this paper, a hydrogel material with efficient antibacterial, hemostatic, self-healing, and injectable properties was designed for the treatment of diabetic wounds. Firstly, quaternary ammonium salts were grafted with oxidized sodium alginate, and quaternized oxidized sodium alginate (QOSA) was synthesized. Due to the introduction of quaternary ammonium group it has antibacterial and hemostatic effects, at the same time, due to the presence of aldehyde group it can be reacted with carboxymethyl chitosan (CMCS) to form a hydrogel through the Schiff base reaction. Furthermore, deer antler blood polypeptide (DABP) was loaded into the hydrogel (QOSA&CMCS&DABP), showing good swelling ratio and bacteriostatic effect. In vitro and in vivo experiments demonstrated that the hydrogel not only quickly inhibited hepatic hemorrhage in mice and reduced coagulation index and clotting time in vitro, but also significantly enhanced collagen deposition at the wound site, accelerating wound healing. This demonstrates that the multifunctional hydrogel materials (QOSA&CMCS&DABP) have promising applications in the acceleration of skin wound healing and antibacterial promotion.

Advances in skin gene therapy: utilizing innovative dressing scaffolds for wound healing, a comprehensive review

The skin, serving as the body's outermost layer, boasts a vast area and intricate structure, functioning as the primary barrier against external threats. Disruptions in the composition and functionality of the skin can lead to a diverse array of skin conditions, such as wounds, burns, and diabetic ulcers, along with inflammatory disorders, infections, and various types of skin cancer. These disorders not only exacerbate concerns regarding skin health and beauty but also have a significant impact on mental well-being. Due to the complexity of these disorders, conventional treatments often prove insufficient, necessitating the exploration of new therapeutic approaches. Researchers develop new therapies by deciphering these intricacies and gaining a thorough understanding of the protein networks and molecular processes in skin. A new window of opportunity has opened up for improving wound healing processes because of recent advancements in skin gene therapy. To enhance skin regeneration and healing, this extensive review investigates the use of novel dressing scaffolds in conjunction with gene therapy approaches. Scaffolds that do double duty as wound protectors and vectors for therapeutic gene delivery are being developed using innovative biomaterials. To improve cellular responses and speed healing, these state-of-the-art scaffolds allow for the targeted delivery and sustained release of genetic material. The most recent developments in gene therapy techniques include RNA interference, CRISPR-based gene editing, and the utilization of viral and non-viral vectors in conjunction with scaffolds, which were reviewed here to overcome skin disorders and wound complications. In the future, there will be rare chances to develop custom methods for skin health care thanks to the combination of modern technology and collaboration among disciplines.

Recent advances in molecular mechanisms of skin wound healing and its treatments

The skin, being a multifaceted organ, performs a pivotal function in the complicated wound-healing procedure, which encompasses the triggering of several cellular entities and signaling cascades. Aberrations in the typical healing process of wounds may result in atypical scar development and the establishment of a persistent condition, rendering patients more vulnerable to infections. Chronic burns and wounds have a detrimental effect on the overall quality of life of patients, resulting in higher levels of physical discomfort and socio-economic complexities. The occurrence and frequency of prolonged wounds are on the rise as a result of aging people, hence contributing to escalated expenditures within the healthcare system. The clinical evaluation and treatment of chronic wounds continue to pose challenges despite the advancement of different therapeutic approaches. This is mainly owing to the prolonged treatment duration and intricate processes involved in wound healing. Many conventional methods, such as the administration of growth factors, the use of wound dressings, and the application of skin grafts, are used to ease the process of wound healing across diverse wound types. Nevertheless, these therapeutic approaches may only be practical for some wounds, highlighting the need to advance alternative treatment modalities. Novel wound care technologies, such as nanotherapeutics, stem cell treatment, and 3D bioprinting, aim to improve therapeutic efficacy, prioritize skin regeneration, and minimize adverse effects. This review provides an updated overview of recent advancements in chronic wound healing and therapeutic management using innovative approaches.

Gelatin-based biomaterials and gelatin as an additive for chronic wound repair

Disturbing or disrupting the regular healing process of a skin wound may result in its progression to a chronic state. Chronic wounds often lead to increased infection because of their long healing time, malnutrition, and insufficient oxygen flow, subsequently affecting wound progression. Gelatin-the main structure of natural collagen-is widely used in biomedical fields because of its low cost, wide availability, biocompatibility, and degradability. However, gelatin may exhibit diverse tailored physical properties and poor antibacterial activity. Research on gelatin-based biomaterials has identified the challenges of improving gelatin's poor antibacterial properties and low mechanical properties. In chronic wounds, gelatin-based biomaterials can promote wound hemostasis, enhance peri-wound antibacterial and anti-inflammatory properties, and promote vascular and epithelial cell regeneration. In this article, we first introduce the natural process of wound healing. Second, we present the role of gelatin-based biomaterials and gelatin as an additive in wound healing. Finally, we present the future implications of gelatin-based biomaterials.

Piperine, quercetin, and curcumin identified as promising natural products for topical treatment of cutaneous leishmaniasis

Leishmania braziliensis (L. braziliensis) causes cutaneous leishmaniasis (CL) in the New World. The costs and the side effects of current treatments render imperative the development of new therapies that are affordable and easy to administer. Topical treatment would be the ideal option for the treatment of CL. This underscores the urgent need for affordable and effective treatments, with natural compounds being explored as potential solutions. The alkaloid piperine (PIP), the polyphenol curcumin (CUR), and the flavonoid quercetin (QUE), known for their diverse biological properties, are promising candidates to address these parasitic diseases. Initially, the in vitro cytotoxicity activity of the compounds was evaluated using U-937 cells, followed by the assessment of the leishmanicidal activity of these compounds against amastigotes of L. braziliensis. Subsequently, a golden hamster model with stationary-phase L. braziliensis promastigote infections was employed. Once the ulcer appeared, hamsters were treated with QUE, PIP, or CUR formulations and compared to the control group treated with meglumine antimoniate administered intralesionally. We observed that the three organic compounds showed high in vitro leishmanicidal activity with effective concentrations of less than 50 mM, with PIP having the highest activity at a concentration of 8 mM. None of the compounds showed cytotoxic activity for U937 macrophages with values between 500 and 700 mM. In vivo, topical treatment with QUE daily for 15 days produced cured in 100% of hamsters while the effectiveness of CUR and PIP was 83% and 67%, respectively. No failures were observed with QUE. Collectively, our data suggest that topical formulations mainly for QUE but also for CUR and PIP could be a promising topical treatment for CL. Not only the ease of obtaining or synthesizing the organic compounds evaluated in this work but also their commercial availability eliminates one of the most important barriers or bottlenecks in drug development, thus facilitating the roadmap for the development of a topical drug for the management of CL caused by L. braziliensis.

Live Imaging of Cutaneous Wound Healing after Rotary Tool Injury in Zebrafish

Cutaneous wounds are common afflictions that follow a stereotypical healing process involving hemostasis, inflammation, proliferation, and remodeling phases. In the elderly and those suffering from vascular or metabolic diseases, poor healing after cutaneous injuries can lead to open chronic wounds susceptible to infection. The discovery of new therapeutic strategies to improve this defective wound healing requires a better understanding of the cellular behaviors and molecular mechanisms that drive the different phases of wound healing and how these are altered with age or disease. The zebrafish provides an ideal model for visualization and experimental manipulation of the cellular and molecular events during wound healing in the context of an intact, living vertebrate. To facilitate studies of cutaneous wound healing in zebrafish, we have developed an inexpensive, simple, and effective method for generating reproducible cutaneous injuries in adult zebrafish using a rotary tool. We demonstrate that our injury system can be used in combination with high-resolution live imaging to monitor skin re-epithelialization, immune cell recruitment and activation, and vessel regrowth in the same animal over time. This injury system provides a valuable experimental platform to study key cellular and molecular events during wound healing in vivo with unprecedented resolution.

Signaling Pathways Triggering Therapeutic Hydrogels in Promoting Chronic Wound Healing

In recent years, there has been a significant increase in the prevalence of chronic wounds, such as pressure ulcers, diabetic foot ulcers, and venous ulcers of the lower extremities. The main contributors to chronic wound formation are bacterial infection, prolonged inflammation, and peripheral vascular disease. However, effectively treating these chronic wounds remains a global challenge. Hydrogels have extensively explored as wound healing dressing because of their excellent biocompatibility and structural similarity to extracellular matrix (ECM). Nonetheless, much is still unknown how the hydrogels promote wound repair and regeneration. Signaling pathways play critical roles in wound healing process by controlling and coordinating cells and biomolecules. Hydrogels, along with their therapeutic ingredients that impact signaling pathways, have the potential to significantly enhance the wound healing process and its ultimate outcomes. Understanding this interaction will undoubtedly provide new insights into developing advanced hydrogels for wound repair and regeneration. This paper reviews the latest studies on classical signaling pathways and potential targets influenced by hydrogel scaffolds in chronic wound healing. This work hopes that it will offer a different perspective in developing more efficient hydrogels for treating chronic wounds.

MicroRNA-409-3p/BTG2 signaling axis improves impaired angiogenesis and wound healing in obese mice

Wound healing is facilitated by neoangiogenesis, a complex process that is essential to tissue repair in response to injury. MicroRNAs are small, noncoding RNAs that can regulate the wound healing process including stimulation of impaired angiogenesis that is associated with type-2 diabetes (T2D). Expression of miR-409-3p was significantly increased in the nonhealing skin wounds of patients with T2D compared to the non-wounded normal skin, and in the skin of a murine model with T2D. In response to high glucose, neutralization of miR-409-3p markedly improved EC growth and migration in human umbilical vein endothelial cells (HUVECs), promoted wound closure and angiogenesis as measured by increased CD31 in human skin organoids, while overexpression attenuated EC angiogenic responses. Bulk mRNA-Seq transcriptomic profiling revealed BTG2 as a target of miR-409-3p, where overexpression of miR-409-3p significantly decreased BTG2 mRNA and protein expression. A 3' untranslated region (3'-UTR) luciferase assay of BTG2 revealed decreased luciferase activity with overexpression of miR-409-3p, while inhibition had opposite effects. Mechanistically, in response to high glucose, miR-409-3p deficiency in ECs resulted in increased mTOR phosphorylation, meanwhile BTG-anti-proliferation factor 2 (BTG2) silencing significantly decreased mTOR phosphorylation. Endothelial-specific and tamoxifen-inducible miR-409-3p knockout mice (MiR-409IndECKO ) with hyperglycemia that underwent dorsal skin wounding showed significant improvement of wound closure, increased blood flow, granulation tissue thickness (GTT), and CD31 that correlated with increased BTG2 expression. Taken together, our results show that miR-409-3p is a critical mediator of impaired angiogenesis in diabetic skin wound healing.

Network Pharmacology Study on Herb Pair Bletilla striata-Galla chinensis in the Treatment of Chronic Skin Ulcers

BACKGROUND

Herb pair Bletilla striata-Galla chinensis (BS-GC) is a classic combination of topical traditional Chinese medicine formulae in the treatment of chronic skin ulcers (CSUs).

OBJECTIVE

The aim of this study is to explore the effective active ingredients of BS-GC, as well as the core targets and signal transduction pathways of its action on CSUs.

METHODS

The ingredients of BS-GC were obtained from TCMSP and HERB databases. The targets of all active ingredients were retrieved from the SwissTargetPrediction database. The targets of CSUs were obtained from OMIM, GeneCards, Drugbank, and DisGeNET databases. A drug-disease target protein-protein interaction (PPI) network was constructed to select the most core targets, and an herb-ingredient-target network was built by utilizing Cytoscape 3.7.2. Furthermore, we performed Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes database (KEGG) analysis and verified the results of network pharmacology through molecular docking.

RESULTS

A total of 40 active ingredients from the herb pair BS-GC were initially screened, and a total of 528 targets were retrieved. Meanwhile, the total number of CSU targets was 1032. Then, the number of common targets between BS-GC and CSUs was 107. The 13 core targets of herb pair BS-GC with CSUs were filtered out according to the PPI network, including AKT1, TNF, EGFR, BCL2, HIF1A, MMP-9, etc. The 5 main core active ingredients were 1-(4-Hydroxybenzyl)-2-methoxy-9,10-dihydrophenanthrene-4,7-diol, 1-(4- Hydroxybenzyl)-4-methoxy-9,10-dihydrophenanthrene-2,7-diol, physcion, dihydromyricetin, and myricetin. The main biological processes were inflammation, oxidative stress, and immune response, involving the AGE-RAGE signaling pathway in diabetic complications, HIF-1 signaling pathway, NF-κB signaling pathway, and calcium signaling pathway. Molecular docking results showed good binding activity between the 5 main core active ingredients and 13 core targets.

CONCLUSION

This study predicted the core targets and signal transduction pathways in the treatment of CSUs to provide a reference for further molecular mechanism research.

A Lower IL-34 Expression Is Associated with Non-Healing Diabetic Foot Ulcers

BACKGROUND

The non-healing of diabetic foot ulcers (DFU) is a major cause of high disability, morbidity, and mortality. Thus, new therapeutic targets and methods to help healing in patients with DFUs are major research hotspots.

OBJECTIVE

This study examined the molecular differences between healing and non-healing DFUs to identify genes associated with DFU healing.

METHODS

Differentially expressed genes (DEGs) were identified by bioinformatics. Samples were collected from patients with healing (n=10) and non-healing (n=10) DFUs from September 2021 to September 2022. Interleukin (IL)-34 expression was measured by ELISA and qRT-PCT. The fibroblasts from healing and non-healing DFU were divided according to their gene signatures and subdivided based on their gene expression profile differences.

RESULTS

A comparison of fibroblast subpopulation characteristics revealed that the proportion of subpopulation 4 was significantly higher in non-healing DFUs than in healing DFUs. Subpopulation 4 had 254 upregulated genes and 2402 downregulated genes in the non-healing compared with the healing DFUs. The DEGs were involved in several biological functions, including cytokine activity, receptor-ligand activity, signaling receptor activator activity, and receptor regulator activity. IL-34 was downregulated in non-healing compared with healing DFUs, suggesting a possible role of IL-34 in DFU healing. In the clinical specimens, IL-34 was significantly downregulated in non-healing DFUs, consistent with the bioinformatics results.

CONCLUSION

IL-34 expression is downregulated in non-healing DFU. IL-34 appears to be involved in DFU healing, but the exact causal relationship remains to be explored.

Changes in gene expression in pressure ulcers debrided by different approaches - a pilot study

Pressure ulcers (PUs), also known as pressure injuries, are chronic wounds that represent potential lifelong complications. Pressure ulcers of a deep category (III and IV) are often indicated for surgical treatment - debridement and surgical reconstruction. Sharp surgical debridement is widely used in the debridement of PUs; however, the Versajet® hydrosurgery system is becoming an increasingly popular tool for tangential excision in surgery due to its numerous advantages. This work focused on the expression of selected genes, especially those associated with oxidative stress, in PUs debrided by two approaches - sharp surgical debridement and debridement using Versajet® hydrosurgery system. Expression of following genes was evaluated: NFE2L2, ACTA2, NFKB1, VEGFA, MKI67, HMOX1, HMOX2, HIF1A, and SOD2. ACTB and PSMB were used as housekeeping genes. So far, five patients have been enrolled in the study. Preliminary results suggest no significant difference in gene expression with different pressure ulcer treatment approaches except NFE2L2, despite the macroscopic differences. However, the results revealed correlations between the expression of some genes, namely HIF1A and SOD2, VEGFA and SOD2 and VEGFA and HIF1A. These results may indicate a connection between hypoxia, oxidative stress, pressure ulcer healing processes and angiogenesis.

Real-time in vivo monitoring of the antimicrobial action of combination therapies in the management of infected topical wounds

The increasing prevalence of non-healing infected wounds has become a serious concern in the clinical practice, being associated to population aging and to the rising prevalence of several chronic conditions such as diabetes. Herein, the evaluation of the bactericidal and antibiofilm effects of the natural antiseptic terpenes thymol and farnesol standing alone or in combination with the standard care antiseptic chlorhexidine was carried out both in vitro and in vivo. The in vitro combinatorial treatment of chlorhexidine associated with those terpenes against Staphylococcus aureus in its planktonic and sessile forms demonstrated a superior antibacterial activity than that of chlorhexidine alone. Real-time in vivo monitoring of infection progression and antimicrobial treatment outcomes were evaluated using the bioluminescent S. aureus strain Xen36. In vivo studies on infected wound splinting murine models corroborated the superior bactericidal effects of the combinatorial treatments here proposed. Moreover, the encapsulation of thymol in electrospun Eudragit® S100 (i.e., a synthetic anionic copolymer of methacrylic acid and ethyl acrylate)-based wound dressings was also carried out in order to design efficient antimicrobial wound dressings.

Chronic venous insufficiency and venous leg ulcers: Aetiology, on the pathophysiology-based treatment

The chronic venous disease covers a wide spectrum of venous disorders that are characterized by severely impaired blood return that primarily affects veins in the lower extremities. Morphological and functional abnormalities of the venous system led to chronic venous insufficiency (CVI), and present as leg heaviness/achiness, edema, telangiectasia, and varices. The term 'chronic venous insufficiency' (CVI) refers to a disease of greater severity. Venous dysfunction is associated with venous hypertension and is associated with venous reflux due to poorly functioning or incompetent venous valves, which ultimately reduces venous return, leading to a cascade of morphological, physiological, and histologic abnormalities such as blood pooling, hypoxia, inflammation, swelling, skin changes (lipodermatosclerosis), and in severe cases, venous leg ulcers (VLU). This review summarizes recent knowledge about the aetiology, risk factors, and pathophysiology of VLU and compared the possibilities of their treatment.

Chitosan-Based Hydrogels for Infected Wound Treatment

Wound infections slow down the healing process and lead to complications such as septicemia, osteomyelitis, and even death. Although traditional methods relying on antibiotics are effective in controlling infection, they have led to the emergence of antibiotic-resistant bacteria. Hydrogels with antimicrobial function become a viable option for reducing bacterial colonization and infection while also accelerating healing processes. Chitosan is extensively developed as antibacterial wound dressings due to its unique biochemical properties and inherent antibacterial activity. In this review, the recent research progress of chitosan-based hydrogels for infected wound treatment, including the fabrication methods, antibacterial mechanisms, antibacterial performance, wound healing efficacy, etc., is summarized. A concise assessment of current limitations and future trends is presented.

Skewing cPLA2α activity toward oxoeicosanoid production promotes neutrophil N2 polarization, wound healing, and the response to sepsis

Uncontrolled inflammation is linked to poor outcomes in sepsis and wound healing, both of which proceed through distinct inflammatory and resolution phases. Eicosanoids are a class of bioactive lipids that recruit neutrophils and other innate immune cells. The interaction of ceramide 1-phosphate (C1P) with the eicosanoid biosynthetic enzyme cytosolic phospholipase A2 (cPLA2) reduces the production of a subtype of eicosanoids called oxoeicosanoids. We investigated the effect of shifting the balance in eicosanoid biosynthesis on neutrophil polarization and function. Knockin mice expressing a cPLA2 mutant lacking the C1P binding site (cPLA2αKI/KI mice) showed enhanced and sustained neutrophil infiltration into wounds and the peritoneum during the inflammatory phase of wound healing and sepsis, respectively. The mice exhibited improved wound healing and reduced susceptibility to sepsis, which was associated with an increase in anti-inflammatory N2-type neutrophils demonstrating proresolution behaviors and a decrease in proinflammatory N1-type neutrophils. The N2 polarization of cPLA2αKI/KI neutrophils resulted from increased oxoeicosanoid biosynthesis and autocrine signaling through the oxoeicosanoid receptor OXER1 and partially depended on OXER1-dependent inhibition of the pentose phosphate pathway (PPP). Thus, C1P binding to cPLA2α suppresses neutrophil N2 polarization, thereby impairing wound healing and the response to sepsis.

An In Vitro Study of Local Oxygen Therapy as Adjunctive Antimicrobial Therapeutic Option for Patients with Periodontitis

Periodontitis is a common global disease caused by bacterial dysbiosis leading to tissue destruction, and it is strongly associated with anaerobic bacterial colonization. Therapeutic strategies such as oxygen therapy have been developed to positively influence the dysbiotic microbiota, and the use of oxygen-releasing substances may offer an added benefit of avoiding systemic effects commonly associated with antibiotics taken orally or hyperbaric oxygen therapy. Therefore, the oxygen release of calcium peroxide (CaO₂) was measured using a dissolved oxygen meter, and CaO₂ solutions were prepared by dissolving autoclaved CaO₂ in sterile filtered and deionized water. The effects of CaO₂ on planktonic bacterial growth and metabolic activity, as well as on biofilms of Streptococcus oralis and Porphyromonas gingivalis, were investigated through experiments conducted under anaerobic conditions. The objective of this study was to investigate the potential of CaO₂ as an antimicrobial agent for the treatment of periodontitis. Results showed that CaO₂ selectively inhibited the growth and viability of P. gingivalis (p < 0.001) but had little effect on S. oralis (p < 0.01), indicating that CaO₂ has the potential to selectively affect both planktonic bacteria and mono-species biofilms of P. gingivalis. The results of this study suggest that CaO₂ could be a promising antimicrobial agent with selective activity for the treatment of periodontitis.

The Role of Chronotype of Patients and Cryoexrtact of Placenta in the Activity of Antioxidant Enzymes in Facial Scar

BACKGROUND: The chronotypical features of people have a significant impact on the course of reparative processes in the patient’s body. Understanding the mechanisms of influence on the course of reparative skin regeneration after planned surgical interventions within the maxillofacial tissues can contribute to improving the provision of medical care to such patients. AIM: The study was aimed to determine role of chronotype of patients and cryoexrtact of placenta in the activity of antioxidant enzymes in facial scar. METHODS: In our study, 60 patients (36 males and 24 females) of the Department of Maxillofacial Surgery of the Poltava Regional Clinical Hospital, Ukraine, aged from 18 to 68 years, who underwent inpatient treatment for planned surgical interventions of the maxillofacial area, were enrolled. At the time of the study, the patients did not have concomitant diseases, but if necessary, all patients could consult by other specialists. The practical section was carried out between September 2019 and August 2021 as follow. According to our study, 60 patients were divided depending on the type of chronotype, which was determined by the Horn-Ostberg questionnaire in Stepanova’s modification and the type of using treatment taking into account different ways of using of cryoextract of placenta. The activities of superoxide dismutase and catalase were determined on the 90th, 180th, and 360th days of observation in the forming scar tissue. We used the method of Chevari et al. to determine the activity of superoxide dismutase. Catalase activity in homogenates of scar tissue was determined according to the method of M.A. Koroliuk. RESULTS: It was noted that the enzymatic activity of catalase in the scar homogenate is characterized by a lower dynamics of changes than the activity of superoxide dismutase. Positive dynamics were noted under the conditions of use in the treatment protocol of placenta cryoextract, which was more pronounced in patients with a morning chronotype. CONCLUSIONS: The most significant changes were observed in the studied indicators of antioxidant protection in patients of the morning chronotype who underwent intrawound administration of cryoextract of the placenta in combination with electrophoresis of this remedy against the background of a standard treatment protocol, especially at earlier terms after surgical treatment.