In vitro and in vivo evaluation of the diabetic wound healing properties of Saffron (Crocus Sativus L.) petals.

Wound healing is a complex process orchestrated by interactions between a variety of cell types, including keratinocytes, fibroblasts, endothelial cells, inflammatory cells, and bioactive factors such as extracellular matrix (ECM) components, growth factors, and cytokines. Chronic wounds exhibit delayed proliferative phase initiation, reduced angiogenesis, impaired ECM synthesis, and persistent inflammatory response. Chronic wounds are one of the main challenges to the healthcare system worldwide, with a high cost for medical services. Hence, investigation of new approaches to accelerate wound healing is essential. Phytomedicines are considered as potential agents for improving the wound healing by accelerating epithelization, collagen synthesis, and angiogenesis. These natural compounds have various advantages including availability, ease of application, and high effectiveness in wound managment. This study aimed to investigate the biological effects of saffron or Crocus sativus L. (C. sativus) petal extract on cell survival, migration, and angiogenesis using MTT, scratch and in vitro tube formation assays. Moreover, the expression of collagen type I alpha 1 (COL1A1) and vascular endothelial growth factor (VEGF) were evaluated in human dermal fibroblasts (HDF)s and human umbilical vein endothelial cells (HUVEC)s, respectively. The effect of the C. sativus extract on the skin of diabetic mice was also monitored. The results showed that C. sativus petal extract promoted the viability and migration of HDFs and HUVECs. Moreover, C. sativus petal extract enhanced the formation of tube-like structures by HUVECs cultured on the Matrigel basement membrane matrix, indicating its potential to stimulate angiogenesis. Gene expression studies have shown the the C. sativus extract increases wound healing by upregulation of COL1A1 and VEGF, which are crucial factors involved in collagen deposition, epithelialization, and angiogenesis. Histological analysis revealed that C. sativus petal extract enhanced vascularity and increased the number of fibroblasts and collagen synthesis, ultimately accelerating wound closure compared to wounds treated with eucerin and commercial ointment in diabetic mice. Therefore, C. sativus petal extract has potential as a herbal treatment to improve the healing of diabetic wounds.

A bioactive composite sponge based on biomimetic collagen fibril and oxidized alginate for noncompressible hemorrhage and wound healing.

The study focuses on developing a bioactive shape memory sponge to address the urgent demand for short-term rapid hemostasis and long-term wound healing in noncompressible hemorrhage cases. A composite sponge was created by spontaneously generating pores and double cross-linking under mild conditions using biomimetic collagen fibril (BCF) and oxidized alginate (OA) as natural backbone, combined with an inert calcium source (Ca) from CaCO3-GDL slow gelation mechanism. The optimized BCF/OACa (5/5) sponge efficiently absorbed blood after compression and recovered to its original state within 11.2 ± 1.3 s, achieving physical hemostatic mechanism. The composite sponge accelerated physiological coagulation by promoting platelet adhesion and activation through BCF, as well as enhancing endogenous and exogenous hemostatic pathways by Ca2+. Compared to commercial PVA expanding hemostatic sponge, the composite sponge reduced bleeding volume and shortened hemostasis time in rat liver injury pick and perforation wound models. Additionally, it stimulated fibroblast migration and differentiation, thus promoting wound healing. It is biodegradable with low inflammatory response and promotes granulation tissue regeneration. In conclusion, this biocomposite sponge provides multiple hemostatic pathways and biochemical support for wound healing, is biologically safe and easy to fabricate, process and use, with significant potential for clinical translation and application.

Progress in chitin/chitosan and their derivatives for biomedical applications: Where we stand.

Chitin and its deacetylated form, chitosan, have demonstrated remarkable versatility in the realm of biomaterials. Their exceptional biocompatibility, antibacterial properties, pro- and anticoagulant characteristics, robust antioxidant capacity, and anti-inflammatory potential make them highly sought-after in various applications. This review delves into the mechanisms underlying chitin/chitosan's biological activity and provides a comprehensive overview of their derivatives in fields such as tissue engineering, hemostasis, wound healing, drug delivery, and hemoperfusion. However, despite the wealth of studies on chitin/chitosan, there exists a notable trend of homogeneity in research, which could hinder the comprehensive development of these biomaterials. This review, taking a clinician's perspective, identifies current research gaps and medical challenges yet to be addressed, aiming to pave the way for a more sustainable future in chitin/chitosan research and application.

Tunicate cellulose nanocrystals strengthened injectable stretchable hydrogel as multi-responsive enhanced antibacterial wound dressing for promoting diabetic wound healing.

The intricate microenvironment of diabetic wounds characterized by hyperglycemia, intense oxidative stress, persistent bacterial infection and complex pH fluctuations hinders the healing process. Herein, an injectable multifunctional hydrogel (QPTx) was developed, which exhibited excellent mechanical performance and triple responsiveness to pH, temperature, and glucose due to dynamic covalent cross-linking involving dynamic Schiff base bonds and phenylboronate esters with phenylboronic-modified quaternized chitosan (QCS-PBA), polydopamine coated tunicate cellulose crystals (PDAn@TCNCs) and polyvinyl alcohol (PVA). Furthermore, the hydrogels can incorporate insulin (INS) drugs to adapt to the complex and variable wound environment in diabetic patients for on-demand drug release that promote diabetic wound healing. Based on various excellent properties of the colloidal materials, the hydrogels were evaluated for self-healing, rheological and mechanical properties, in vitro insulin response to pH/temperature/glucose release, antibacterial, antioxidant, tissue adhesion, coagulation, hemostasis in vivo and in vitro, and biocompatibility and biodegradability. By introducing PDAn@TCNCs particles, the hydrogel has photothermal antibacterial activity, enhanced adhesion and oxidation resistance. We further demonstrated that these hydrogel dressings significantly improved the healing process compared to commercial dressings (Tegaderm™) in full-layer skin defect models. All indicated that the glucose-responsive QPTx hydrogel platform has great potential for treating diabetic wounds.

Effect of Topical Losartan in the Treatment of Established Corneal Fibrosis in Rabbits.

Purpose: The purpose of this study was to evaluate the safety and efficacy of topical losartan in the therapeutic treatment of established corneal scaring fibrosis at 1 month after alkali burn in rabbits. Methods: Standardized alkali burns were performed in 1 eye of 24 rabbits with 0.75N NaOH for 15 seconds. Corneas were allowed to heal and develop scaring of the cornea for 1 month. Twelve eyes per group were treated with 50 µL of topical 0.8 mg/mL losartan in balanced salt solution (BSS), pH 7.0, and 12 eyes were treated with vehicle BSS 6 times per day. Six corneas were analyzed at 1 week or 1 month in each group. Standardized slit lamp photographs were obtained at the end point for each cornea and opacity was quantitated using ImageJ. Corneoscleral rims were cryofixed in optimum cutting temperature (OCT) solution and combined duplex immunohistochemistry for myofibroblast marker alpha-smooth muscle actin (α-SMA), mesenchymal cell marker vimentin, and TUNEL assay for apoptosis was performed on all corneas. Results: Topical losartan was effective in the treatment of established stromal fibrosis following alkali burn injury to the rabbit cornea. Stromal myofibroblast density was decreased and stromal cell apoptosis was increased (included both α-SMA-positive myofibroblasts and α-SMA-negative, vimentin-positive cells) at both 1 week and 1 month in the topical losartan-treated compared with vehicle-treated groups. Conclusions: Topical losartan is effective in the treatment of established stromal fibrosis in rabbits. Most myofibroblasts disappear from the stroma within the first month of losartan treatment. Longer treatment with topical losartan is needed to allow time for corneal fibroblast regeneration of the epithelial basement membrane (in coordination with epithelial cells) and the removal of disordered extracellular matrix produced by myofibroblasts.

The efficacy of topically applied Sappan wood (Caesalpinia sappan L.) ethanol extract during incision wound healing in albino rats.

Background: Medical manifestations in the form of incisions, burns, and trauma will trigger a natural wound-healing process that involves complex interactions between cells. Brazilin and other secondary metabolites found in Sappan wood have numerous bioactive qualities, including anti-inflammatory, anti-cancer, and antioxidant properties. Aim: This study aimed to investigate the efficacy of Sappan wood (Caesalpinia Sappan L.) ethanol extract topically on the incision wound healing of albino rats. Methods: Twenty male rats were randomly assigned into five groups with four replications, i.e., (C-) was treated ointment-based, (C+) was treated with 10% povidone-iodine, (T1, T2, and T3 groups) were treated with Sappan wood extract concentration for 6.5%, 15%, and 30%, respectively. The treatment was topically administered to wounded areas twice a day for 15 days. Wound healing was evaluated histologically as the following parameters collagen deposition, polymorphonuclear neutrophils (PMN), angiogenesis, and fibrosis degree using H&E staining. IL-2 level was evaluated using the enzyme-linked immunosorbent assay (ELISA) method. Wound length reduction was calculated on days 8 and 15. Results: As a result, the 6.5% (T1), 15% (T2), and 30% (T3) Sappan wood extract groups were improved significantly (p < 0.05) compared to ointment-based (C-) and povidone-iodine (C+) groups on the collagen deposition, PMN, angiogenesis, fibrosis degree, and IL-2 level. In particular, the 6.5% (T1) Sappan wood extract group was highlighted significantly (p < 0.05) compared to other groups, evidenced by the improvisation of wound healing parameters and reduction of wound length on days 8 and 15. Conclusion: In conclusion, a 6.5% Sappan wood extract revealed its applicability to improve incision wound healing in albino rats.

Influence of azathioprine on healing of exposed dogs' dental pulp capped with three different materials.

Background: Azathioprine is one of the earliest immunosuppressants prescribed for several autoimmune diseases. Yet there is a lack of research on the impact of azathioprine on pulp healing following the pulp capping procedure. Aim: This study aimed to investigate the effect of azathioprine on the healing ability of mechanically exposed dogs' dental pulps following direct pulp capping with mineral trioxide aggregate (MTA), bio-aggregates (BA), and Calcium hydroxide (Ca(OH)2). Methods: Four mongrel dogs were randomly assigned to two groups (two dogs/30 teeth in each group): immunosuppressed (group I) and control (group II). Group I received azathioprine for two months before surgical treatments and until the dogs were euthanized. Fifteen class V buccal cavities were performed in each dog. Each group was randomly divided into three subgroups (10 teeth each) based on the pulp capping substance. The pulps in subgroups A, B, and C were immediately capped with MTA, BA, and Ca(OH)2, respectively. Inflammation and dentine bridge development were histopathologically evaluated and scored at one and two months. The data were statistically analyzed. Results: The immunosuppressed group exhibited statistically greater inflammatory cell count and decreased dentine bridge thickness, compared to the control group in all subgroups (p < 0.05). Conclusion: Azathioprine has an adverse effect on the healing of exposed dogs' dental pulp following direct pulp capping with MTA, BA, and Ca(OH)2. Therefore, patients using azathioprine as an immunosuppressive medication may experience delayed healing of mechanically exposed pulps following capping with MTA, BA, or Ca(OH)2.

Protection of stromal cell-derived factor-1 SDF-1/CXCL12 against proteases yields improved skin wound healing.

SDF-1/CXCL12 is a unique chemotactic factor with multiple functions on various types of precursor cells, all carrying the cognate receptor CXCR4. Whereas individual biological functions of SDF-1/CXCL12 have been well documented, practical applications in medicine are insufficiently studied. This is explained by the complex multifunctional biology of SDF-1 with systemic and local effects, critical dependence of SDF-1 activity on aminoterminal proteolytic processing and limited knowledge of applicable modulators of its activity. We here present new insights into modulation of SDF-1 activity in vitro and in vivo by a macromolecular compound, chlorite-oxidized oxyamylose (COAM). COAM prevented the proteolytic inactivation of SDF-1 by two inflammation-associated proteases: matrix metalloproteinase-9/MMP-9 and dipeptidylpeptidase IV/DPPIV/CD26. The inhibition of proteolytic inactivation was functionally measured by receptor-mediated effects, including intracellular calcium mobilization, ERK1/2 phosphorylation, receptor internalization and chemotaxis of CXCR4-positive cells. Protection of SDF-1/CXCL12 against proteolysis was dependent on electrostatic COAM-SDF-1 interactions. By in vivo experiments in mice, we showed that the combination of COAM with SDF-1 delivered through physiological fibrin hydrogel had beneficial effect for the healing of skin wounds. Collectively, we show that COAM protects SDF-1 from proteolytic inactivation, maintaining SDF-1 biological activities. Thus, protection from proteolysis by COAM represents a therapeutic strategy to prolong SDF-1 bioavailability for wound healing applications.

A potential therapeutic strategy of an innovative probiotic formulation toward topical treatment of diabetic ulcer: an in vivo study.

BACKGROUND: The probiotic potential of Lacticacid bacteria has been studied in various medical complications, from gastrointestinal diseases to antibiotic resistance infections recently. Moreover, diabetic ulcer (DU) is known as one of the most significant global healthcare concerns, which comprehensively impacts the quality of life for these patients. Given that the conventional treatments of DUs have failed to prevent later complications completely, developing alternative therapies seems to be crucial. METHODS: We designed the stable oleogel-based formulation of viable probiotic cells, including Lactobacillus rhamnosus (L. rhamnosus), Lactobacillus casei (L. casei), Lactobacillus fermentum (L. fermentum), and Lactobacillus acidophilus (L. acidophilus) individually to investigate their effect on wound healing process as an in vivo study. The wound repair process was closely monitored regarding morphology, biochemical, and histopathological changes over two weeks and compared it with the effects of topical tetracycline as an antibiotic approach. Furthermore, the antibiofilm activity of probiotic bacteria was assessed against some common pathogens. RESULTS: The findings indicated that all tested lactobacillus groups (excluded L. casei) included in the oleogel-based formulation revealed a high potential for repairing damaged skin due to the considerably more levels of hydroxyproline content of tissue samples along with the higher numerical density of mature fibroblasts cell and volume density of hair follicles, collagen fibrils, and neovascularization in comparison with antibiotic and control groups. L. acidophilus and L. rhamnosus showed the best potential of wound healing among all lactobacillus species, groups treated by tetracycline and control groups. Besides, L. rhamnosus showed a significant biofilm inhibition activity against tested pathogens. CONCLUSIONS: This experiment demonstrated that the designed formulations containing probiotics, particularly L. acidophilus and L. rhamnosus, play a central role in manipulating diabetic wound healing. It could be suggested as an encouraging nominee for diabetic wound-healing alternative approaches, though further studies in detailed clinical trials are needed.

Electrospun nanofibrous wound dressings with enhanced efficiency through carbon quantum dots and citrate incorporation.

Nanofibers show promise for wound healing by facilitating active agent delivery, moisture retention, and tissue regeneration. However, selecting suitable dressings for diverse wound types and managing varying exudate levels remains challenging. This study synthesized carbon quantum dots (CQDs) from citrate salt and thiourea using a hydrothermal method. The CQDs displayed antibacterial activity against Staphylococcus aureus and Escherichia coli. A nanoscaffold comprising gelatin, chitosan, and polycaprolactone (GCP) was synthesized and enhanced with silver nanoparticle-coated CQDs (Ag-CQDs) to form GCP-Q, while citrate addition yielded GCP-QC. Multiple analytical techniques, including electron microscopy, FT-IR spectroscopy, dynamic light scattering, UV-Vis, photoluminescence, X-ray diffraction, porosity, degradability, contact angle, and histopathology assessments characterized the CQDs and nanofibers. Integration of CQDs and citrate into the GCP nanofibers increased porosity, hydrophilicity, and degradability-properties favorable for wound healing. Hematoxylin and eosin staining showed accelerated wound closure with GCP-Q and GCP-QC compared to GCP alone. Overall, GCP-Q and GCP-QC nanofibers exhibit significant potential for skin tissue engineering applications.

Mechanism of action of montmorillonite powder on injury and repair factors in Stage II pressure ulcers in model mice.

BACKGROUND: This study aims to elucidate the therapeutic effects and underlying mechanisms of montmorillonite powder on wound healing in mice with Stage II pressure ulcers, thereby providing a robust foundation for its clinical application in the treatment of such ulcers. MATERIALS AND METHODS: Sixty 8-week-old specific pathogen-free male BALB/c mice were randomly allocated into three groups: a model group (where Stage II pressure ulcers were induced using the magnet pressure method and the wounds were dressed with gauze soaked in 0.9% sodium chloride solution), a treatment group (where, following the induction of Stage II pressure ulcer models, wounds were uniformly treated with montmorillonite powder), and a control group (where magnets were placed in the same location without exerting magnetic pressure). Skin histopathology was assessed via light microscopy. Wound healing progress over various intervals was quantified utilizing Image-Pro Plus software. Histopathological alterations in the wounds were examined through hematoxylin and eosin (H&E) staining. The expression of growth factor proteins within the wound tissue was analyzed using the streptavidin-peroxidase method. Furthermore, the levels of vascular endothelial growth factor (VEGF), collagen types I and III (COL-I, COL-III) proteins were quantified via Western blotting, serum concentrations of inflammatory mediators in mice were determined by enzyme-linked immunosorbent assay, and the levels of oxidative stress markers in wound tissues were measured using UV-visible spectrophotometry. RESULTS: The treatment group exhibited significantly reduced serum levels of interleukin-1ß, interleukin-6, and tumor necrosis factor-alpha, and elevated levels of interleukin-4 compared to the model group (p < 0.05). Additionally, the expression of transforming growth factor-beta1, basic fibroblast growth factor, epidermal growth factor, VEGF, COL-I, and COL-III proteins in wound tissues was significantly higher in the treatment group than in the model group (p < 0.05). Levels of superoxide dismutase and glutathione peroxidase in wound tissues were higher, and levels of malondialdehyde were lower in the treatment group compared to the model group (p < 0.05). CONCLUSION: Montmorillonite powder facilitates wound healing and augments the healing rate of Stage II pressure ulcers in model mice. Its mechanism of action is likely associated with mitigating wound inflammation, reducing oxidative stress damage, promoting angiogenesis, and enhancing the synthesis of growth factors and collagen.

Effectiveness of silver and iodine dressings on wound healing: a systematic review and meta-analysis.

OBJECTIVE: To evaluate the effects of silver and iodine dressings on healing time, healing rate, exudate amount, pain and anti-infective efficacy. DESIGN: Systematic review and meta-analysis. DATA SOURCES: Databases including PubMed, Cochrane Library, Embase, Web of Science and CINAHL were surveyed up to May 2024. ELIGIBILITY CRITERIA: Randomised controlled trials comparing silver and iodine dressings on wound healing in humans. DATA EXTRACTION AND SYNTHESIS: Evidence certainty was evaluated using the Grading of Recommendations, Assessment, Development, and Evaluation approach. Data extraction was done independently by two reviewers, with the risk of bias assessed using the Cochrane tool. Narrative synthesis was performed to evaluate the effects of silver and iodine dressings on healing time, healing rate, pain, exudate amount and anti-infective efficacy. Meta-analysis using Review Manager V.5.4 calculated standardised mean differences for healing time and relative risks for rate to quantify the impacts of the treatments. RESULTS: 17 studies (18 articles) were included. The meta-analysis indicated that silver dressings significantly reduced healing time compared with iodine dressings (SMD=-0.95, 95% CI -1.62 to -0.28, I2=92%, p=0.005, moderate-quality evidence), with no significant difference in enhancing healing rate (RR=1.29, 95% CI 0.90 to 1.85, I2=91%, p=0.16, low-quality evidence). Based on low-quality evidence, for exudate amount (3/17), 66.7% (2/3) of the studies favoured silver dressings over iodine in reducing exudate volume. For pain (7/17), 57.1% (4/7) of the studies reported no significant difference between silver and iodine dressings, while 42.9% (3/7) studies indicated superior pain relief with silver dressings. For anti-infective efficacy (11/13), 54.5% (6/11) of the studies showed equivalence between silver and iodine dressings, while 36.4% (4/11) suggested greater antibacterial efficacy for silver. CONCLUSION: Silver dressings, demonstrating a comparable healing rate to iodine dressings, significantly reduce healing time, suggesting their potential as a superior adjunct in wound care. PROSPERO REGISTRATION NUMBER: CRD42020199602.

Astragalus polysaccharide-containing 3D-printed scaffold for traumatized skin repair and proteomic study.

Astragalus polysaccharide-containing 3D-printed scaffold shows great potential in traumatic skin repair. This study aimed to investigate its repairing effect and to combine it with proteomic technology to deeply resolve the related protein expression changes. Thirty SD rats were divided randomly into three groups (n = 10 per group): the sham-operated group, the model group and the scaffold group. Subsequently, we conducted a comparative analysis on trauma blood perfusion, trauma healing rate, histological changes, the expression of the YAP/TAZ signalling pathway and angiogenesis-related factors. Additionally, neonatal skin tissues were collected for proteomic analysis. The blood perfusion volume and wound healing recovery in the scaffold group were better than that in the model group (p < 0.05). The protein expression of STAT3, YAP, TAZ and expression of vascular-related factor A (VEGFA) in the scaffold group was higher than that in the model group (p < 0.05). Proteomic analysis showed that there were 207 differential proteins common to the three groups. Mitochondrial function, immune response, redox response, extracellular gap and ATP metabolic process were the main groups of differential protein changes. Oxidative phosphorylation, metabolic pathway, carbon metabolism, calcium signalling pathway, etc. were the main differential metabolic pathway change groups. Astragalus polysaccharide-containing 3D-printed scaffold had certain reversals of protein disorder. The Astragalus polysaccharide-containing 3D-printed scaffold may promote the VEGFs by activating the YAP/TAZ signalling pathway with the help of STAT3 into the nucleus, accelerating early angiogenesis of the trauma, correcting the protein disorder of the trauma and ultimately realizing the repair of the wound.

Advancements and Challenges of Nanostructured Lipid Carriers for Wound Healing Applications.

The current treatments for wound healing still exhibit drawbacks due to limited availability at the action sites, susceptibility to degradation, and immediate drug release, all of which are detrimental in chronic conditions. Nano-modification strategies, offering various advantages that can enhance the physicochemical properties of drugs, have been employed in efforts to maximize the efficacy of wound healing medications. Nowadays, nanostructured lipid carriers (NLCs) provide drug delivery capabilities that can safeguard active compounds from environmental influences and enable controlled release profiles. Consequently, NLCs are considered an alternative therapy to address the challenges encountered in wound treatment. This review delves into the application of NLCs in drug delivery for wound healing, encompassing discussions on their composition, preparation methods, and their impact on treatment effectiveness. The modification of drugs into the NLC model can be facilitated using relatively straightforward technologies such as pressure-based processes, emulsification techniques, solvent utilization methods, or phase inversion. Moreover, NLC production with minimal material compositions can accommodate both single and combination drug delivery. Through in vitro, in vivo, and clinical studies, it has been substantiated that NLCs can enhance the therapeutic potential of various drug types in wound healing treatments. NLCs enhance efficacy by reducing the active substance particle size, increasing solubility and bioavailability, and prolonging drug release, ensuring sustained dosage at the wound site for chronic wounds. In summary, NLCs represent an effective nanocarrier system for optimizing the bioavailability of active pharmacological ingredients in the context of wound healing.

Bacteria-Derived Cellulose Membranes Modified with Graphene Oxide-Silver Nanoparticles for Accelerating Wound Healing.

This study reports on the modification of bacterial cellulose (BC) membranes produced by static fermentation of Komagataeibacter xylinus bacterial strains with graphene oxide-silver nanoparticles (GO-Ag) to yield skin wound dressings with improved antibacterial properties. The GO-Ag sheets were synthesized through chemical reduction with sodium citrate and were utilized to functionalize the BC membranes (BC/GO-Ag). The BC/GO-Ag composites were characterized to determine their surface charge, morphology, exudate absorption, antimicrobial activity, and cytotoxicity by using fibroblast cells. The antimicrobial activity of the wound dressings was assessed against Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa. The results indicate that the BC/GO-Ag dressings can inhibit ∼70% of E. coli cells. Our findings also revealed that the porous BC/GO-Ag antimicrobial dressings can efficiently retain 94% of exudate absorption after exposure to simulated body fluid (SBF) for 24 h. These results suggest that the dressings could absorb excess exudate from the wound during clinical application, maintaining adequate moisture, and promoting the proliferation of epithelial cells. The BC/GO-Ag hybrid materials exhibited excellent mechanical flexibility and low cytotoxicity to fibroblast cells, making excellent wound dressings able to control bacterial infectious processes and promote the fast healing of dermal lesions.

A bitter flavonoid gum from Dorema aucheri accelerate wound healing in rats: Involvement of Bax/HSP 70 and hydroxyprolin mechanisms.

BACKGROUND: Dorema aucheri gum (DAG) is a bitter flavonoid gum widely used for numerous medicinal purposes including wound recovery. The present work investigates the acute toxicity and wound-healing effects of DAG in excisional skin injury in rats. MATERIALS AND METHODS: Sprague Dawley rats (24) were clustered into four groups, each rat had a full-thickness excisional dorsal neck injury (2.00 cm) and addressed with 0.2 mL of the following treatments for 15 days: Group A (vehicle), rats addressed with normal saline; Group B, rats received intrasite gel; C and D, rats addressed with 250 and 500 mg/kg of DAG, respectively. RESULTS: The results revealed the absence of any toxic signs in rats who received oral dosages of 2 and 5 g/kg of DAG. Wound healing was significantly accelerated following DAG treatments indicated by smaller open areas and higher wound contraction percentages compared to vehicle rats. Histological evaluation revealed higher fibroblast formation, collagen deposition, and noticeably lower inflammatory cell infiltration in granulated skin tissues of DAG-addressed rats compared to vehicle rats. DAG treatment caused significant modulation of immunohistochemical proteins (decreased Bax and increased HSP 70) and inflammatory mediators (reduced TNF-α, IL-6, and magnified IL-10), which were significantly varied compared to vehicle rats. Moreover, topical DAG treatment led to significant upregulation of the hydroxyproline (HDX) (collagen) and antioxidant content. At the same time, decreased the lipid peroxidation (MDA) levels in healed tissues obtained from DAG-treated rats. CONCLUSION: The present wound contraction by DAG might be linked with the modulatory effect of its phytochemicals (polysaccharides, flavonoids, and phenolic) on the cellular mechanisms, which justify their folkloric use and provokes further investigation as therapeutic drug additives for wound contraction.

Maleimide conjugated PEGylated liposomal antibiotic to combat multi-drug resistant Escherichia coli and Klebsiella pneumoniae with enhanced wound healing potential.

Antibiotic resistance is a significant threat, leaving us vulnerable to bacterial infections. Novel strategies are needed to combat bacterial resistance beyond discovering new antibiotics. This research focuses on using maleimide conjugated PEGylated liposomes (Mal-PL-Ab) to individually encapsulate a variety of antibiotics (ceftriaxone, cephalexin, doxycycline, piperacillin, ampicillin, and ceftazidime) and enhance their delivery against multi-drug resistant (MDR) bacteria like Escherichia coli (E. coli) and Klebsiella pneumoniae (K. pneumoniae). Mal-PL-Ab, with an average size of 84.2 nm ± 4.32 nm, successfully encapsulated these antibiotics with an encapsulation efficiency of 37.73 ± 3.19%. Compared to non-PEGylated liposomes (L-Ab), Mal-PL-Ab exhibited reduced toxicity in human dermal cells, emphasizing the importance of PEGylation in minimizing adverse effects. Mal-PL-Ab significantly decreased the minimum inhibitory concentration (MIC) values against both E. coli and K. pneumoniae by 9.33-fold and eightfold reduction (compared to non-PEGylated liposomes with 2.33-fold and 2.33fold reduction), respectively, indicating enhanced efficacy against MDR strains. Furthermore, in vitro scratch assay and gene expression analysis of human dermal fibroblast revealed that Mal-PL-Ab promoted cell proliferation, migration, and wound healing through upregulation of cell cycle, DNA repair, and angiogenesis-related genes. Harnessing the power of encapsulation, Mal-PL-Ab presents a novel avenue for enhanced antibiotic delivery and wound healing, potentially transcending the limitations of traditional options.

GelMA loaded with platelet lysate promotes skin regeneration and angiogenesis in pressure ulcers by activating STAT3.

Pressure ulcers (PU) are caused by persistent long-term pressure, which compromises the integrity of the epidermis, dermis, and subcutaneous adipose tissue layer by layer, making it difficult to heal. Platelet products such as platelet lysate (PL) can promote tissue regeneration by secreting numerous growth factors based on clinical studies on skin wound healing. However, the components of PL are difficult to retain in wounds. Gelatin methacrylate (GelMA) is a photopolymerizable hydrogel that has lately emerged as a promising material for tissue engineering and regenerative medicine. The PL liquid was extracted, flow cytometrically detected for CD41a markers, and evenly dispersed in the GelMA hydrogel to produce a surplus growth factor hydrogel system (PL@GM). The microstructure of the hydrogel system was observed under a scanning electron microscope, and its sustained release efficiency and biological safety were tested in vitro. Cell viability and migration of human dermal fibroblasts, and tube formation assays of human umbilical vein endothelial cells were applied to evaluate the ability of PL to promote wound healing and regeneration in vitro. Real-time polymerase chain reaction (PCR) and western blot analyses were performed to elucidate the skin regeneration mechanism of PL. We verified PL's therapeutic effectiveness and histological analysis on the PU model. PL promoted cell viability, migration, wound healing and angiogenesis in vitro. Real-time PCR and western blot indicated PL suppressed inflammation and promoted collagen I synthesis by activating STAT3. PL@GM hydrogel system demonstrated optimal biocompatibility and favorable effects on essential cells for wound healing. PL@GM also significantly stimulated PU healing, skin regeneration, and the formation of subcutaneous collagen and blood vessels. PL@GM could accelerate PU healing by promoting fibroblasts to migrate and secrete collagen and endothelial cells to vascularize. PL@GM promises to be an effective and convenient treatment modality for PU, like chronic wound treatment.

Efficacy and Safety of Honey Dressings in the Management of Chronic Wounds: An Updated Systematic Review and Meta-Analysis.

Chronic wounds impose a substantial economic burden on healthcare systems and result in decreased productivity. Honey possesses diverse properties, rendering it a promising, cost-effective, and efficacious intervention strategy for the management of chronic wounds. However, the findings are controversial. We have presented an updated and comprehensive systematic review and meta-analysis to evaluate the efficacy and safety of honey dressings in the management of chronic wounds. Nine electronic databases were systematically searched to identify relevant studies published prior to 22 March 2024. A total of eight studies, including 906 individuals that met the inclusion criteria, were incorporated. The findings demonstrated a significant acceleration in wound healing time with honey dressings (MD = -17.13, 95% CI -26.37 to -7.89, p = 0.0003) and an increase in the percentage of wound healing (MD = 18.31, 95% CI 8.86 to 27.76, p = 0.0001). No statistically significant differences were observed in the healing rate (RR = 2.00, 95% CI 0.78 to 5.10, p = 0.15), clearance time of bacteria (MD = -11.36, 95% CI: -25.91 to 3.18, p = 0.13) and hospital stay duration. Honey may decrease the VAS score but may increase the incidence of painful discomfort during treatment. The topical application of honey is an effective therapeutic approach for managing chronic wounds, but the quality of the evidence was very low due to the quality of risk of bias, inconsistency, and publication bias, highlighting the necessity for larger-scale studies with adequately powered RCTs to ensure the safety and efficacy of honey dressings in chronic wound healing.

Sprayable biomimetic double mask with rapid autophasing and hierarchical programming for scarless wound healing.

Current sprayable hydrogel masks lack the stepwise protection, cleansing, and nourishment of extensive wounds, leading to delayed healing with scarring. Here, we develop a sprayable biomimetic double wound mask (BDM) with rapid autophasing and hierarchical programming for scarless wound healing. The BDMs comprise hydrophobic poly (lactide-co-propylene glycol-co-lactide) dimethacrylate (PLD) as top layer and hydrophilic gelatin methacrylate (GelMA) hydrogel as bottom layer, enabling swift autophasing into bilayered structure. After photocrosslinking, BDMs rapidly solidify with strong interfacial bonding, robust tissue adhesion, and excellent joint adaptiveness. Upon implementation, the bottom GelMA layer could immediately release calcium ion for rapid hemostasis, while the top PLD layer could maintain a moist, breathable, and sterile environment. These traits synergistically suppress the inflammatory tumor necrosis factor-α pathway while coordinating the cyclic guanosine monophosphate/protein kinase G-Wnt/calcium ion signaling pathways to nourish angiogenesis. Collectively, our BDMs with self-regulated construction of bilayered structure could hierarchically program the healing progression with transformative potential for scarless wound healing.