Full-thickness Wound Model Research Articles

Injectable self-healing alginate/PEG hydrogels cross-linked via thiol-Michael addition bonds for hemostasis and wound healing

In this study, an alginate/PEG hydrogel was developed via a thiol-Michael addition reaction between oxidized quinone of catechols on dopamine-grafted sodium alginate (SA-DA) and sulfhydryl groups of 4-arm polyethylene glycol tetra-thiol (4-arm PEG-SH) under mildly basic conditions. Through the formation of thiol-terminated catechol groups, the accompanying oxidized catechols are reduced, significantly strengthening the internal network structure of the hydrogel and improving tissue adhesion. Meanwhile, the hydrogels have excellent self-healing properties due to the dynamic non-covalent bonds between the groups. Adjustment of hydrogel properties by varying the mass ratio of two hydrogel precursors. Due to the high content of thiol-terminated catechol groups, the Gel 3 exhibited good tissue adhesion, rapid self-healing ability, and other multifunctions beneficial to wound healing, including killing of E. coli and S. aureus, rapid hemostasis and promoting migration of L929 cells. The full-thickness skin wound model shows that the hydrogel dressing significantly accelerated wound contraction, with increased granulation tissue thickness, collagen disposition, and enhanced vascularization, thus promoting wound healing. Therefore, the thiol-Michael addition reaction is an effective method for creating multifunctional hydrogels, and the injectable self-healing alginate/PEG hydrogels prepared in this way could be used in the biomedical area as wound healing dressing materials.

Evaluation of a Kenaf Nanocrystalline Cellulose-based Hydrogel Containing Platelet Lysate for Full-thickness Wound Healing

Introduction: Healing full-thickness wounds is often challenging and time-consuming, with complications such as scarring and infections. The standard treatment, split skin grafting, has limitations due to the availability of healthy donors and suitability for immunocompromised patients. Method: Autologous platelet lysate (PL) has been popular for tissue regenerative potential because it contains growth factors (GF) and is a safer option for bedridden patients with weak immune systems. However, PL has inconsistent clinical efficacy, high costs, and a short half-life. To address these issues, this study explores a novel delivery system by fabricating a chitosan/nanocrystalline cellulose (CS/NCC) hydrogel to sustainably deliver autologous PL to the wound site. Notably, NCC was prepared from kenaf bast fibers using acid hydrolysis and integrated into the CS matrix through physical entrapment without any chemical crosslinkers. The composite hydrogel was then enriched with autologous PL and further characterized for its physicochemical properties, in vitro GF release, and compatibility with skin cells. At the molecular level, gene expression of wound healing genes was facilitated using qPCR, revealing that the PL-supplemented hydrogel upregulated the expression of extracellular matrix genes. An in vivo study using a full-thickness wound model demonstrated that the CS-NCC-PL hydrogel dressing achieved 81.8% wound closure within 14 days, compared to the control groups. Result: Histological analysis indicated enhanced re-epithelialization, angiogenesis, and collagen deposition. Particularly, the CS-NCC-PL hydrogel group showed a significantly higher hydroxyproline content (60.62 ± 11.46 μg/100 mg) by day 14. Immunohistochemistry results revealed elevated levels of α-SMA and CD31, markers of myofibroblast presence and angiogenesis, peaking at day 7. Conclusion: These findings suggest that the CS-NCC-PL hydrogel is a promising personalized wound dressing for bedridden patients, offering improved healing outcomes in hospital settings.

Inhibition of Ubiquitin C-Terminal Hydrolase L1 Facilitates Cutaneous Wound Healing via Activating TGF-β/Smad Signalling Pathway in Fibroblasts.

Ubiquitin C-terminal hydrolase L1 (UCHL1) plays vital roles in cell proliferation, angiogenesis, inflammation and oxidative stress. Nevertheless, it is unclear whether UCHL1 could regulate the biologic behaviour of cells and ultimately influences wound healing. We aim to illustrate the roles and the underlying mechanism of UCHL1 in cutaneous wound healing. Murine full-thickness excisional wound model was utilised to study the effects of UCHL1 on wound healing through topical administration of the UCHL1 inhibitor LDN57444, followed by assessment of wound areas and histological alterations. Subsequently, ethynyldeoxyuridine, scratch and transwell assays were performed to examine fibroblast migration and proliferation. The extracellular matrix (ECM)-related genes expression and transforming growth factor-β (TGF-β)/Smad signalling pathways activation were investigated by immuno-fluorescent staining, Western blots and quantitative reverse transcription polymerase chain reaction. We identified elevated UCHL1 expression in non-healing wound tissues. The UCHL1 expression displayed a dynamic change and reached a peak on Day-7 post-wounding during the healing process in mice. Cutaneous administration of LDN57444 promoted wound healing by facilitating collagen deposition, myofibroblast activation and angiogenesis. Invitro experiments demonstrated that UCHL1 concentration dependently inhibited migration, ECM synthesis and activation of human dermal fibroblasts, which was mechanistically related to downregulation of TGF-β/Smad signalling. Furthermore, these effects could be reversed by TGF-β inhibitor SB431542. Our findings reveal that UCHL1 is a negative regulator of cutaneous wound healing and considered as a novel prospective therapeutic target for effective wound healing.

Photo-Crosslinked Pro-Angiogenic Hydrogel Dressing for Wound Healing.

Severe burns are one of the most devastating injuries, in which sustained inflammation and ischemia often delay the healing process. Pro-angiogenic growth factors such as vascular endothelial growth factor (VEGF) have been widely studied for promoting wound healing. However, the short half-life and instability of VEGF limit its clinical applications. In this study, we develop a photo-crosslinked hydrogel wound dressing from methacrylate hyaluronic acid (MeHA) bonded with a pro-angiogenic prominin-1-binding peptide (PR1P). The materials were extruded in wound bed and in situ formed a wound dressing via exposure to short-time ultraviolet radiation. The study shows that the PR1P-bonded hydrogel significantly improves VEGF recruitment, tubular formation, and cell migration in vitro. Swelling, Scanning Electron Microscope, and mechanical tests indicate the peptide does not affect the overall mechanical and physical properties of the hydrogels. For in vivo studies, the PR1P-bonded hydrogel dressing enhances neovascularization and accelerates wound closure in both deep second-degree burn and full-thickness excisional wound models. The Western blot assay shows such benefits can be related to the activation of the VEGF-Akt signaling pathway. These results suggest this photo-crosslinked hydrogel dressing efficiently promotes VEGF recruitment and angiogenesis in skin regeneration, indicating its potential for clinical applications in wound healing.

All-natural hydrogel composed of carboxymethyl chitosan and oxidized dextran for promoting wound healing by immune-microenvironment regulation

Chronic wound treatment has always been a major clinical challenge owing to complex and dynamic wound microenvironment. The design and development of effective management with antimicrobial activity, ROS-scavenging and regulation immune response is vital for tissue repair. Herein, we developed puerarin (PUE) loaded a double network hydrogel consisting of methacrylated carboxymethyl chitosan and oxidized dextran with Schiff base and photo-crosslinking reaction. The composite hydrogel presented fast self-healing and outstanding compressive performance to bear deformation. The hydrogel exhibits a cumulative drug release pattern with biphasic release, which offers great potential for accelerating tissue healing at all stages of wounding. In addition, the hydrogel has good biocompatibility, antimicrobial ability and tube-forming ability in vitro. The full-thickness skin wound model of Staphylococcus aureus infection showed that the hydrogel dressing can accelerate tissue repair. This study demonstrated that the design of combing natural biomacromolecules with traditional Chinese medicine could be severed as a promising candidate biomaterial for skin tissue recovery.

Self-assembled ROS-triggered Bletilla striata polysaccharide-releasing hydrogel dressing for inflammation-regulation and enhanced tissue-healing

The antimicrobial and pro-healing properties remain critical clinical objectives for skin wound management. However, the escalating problem of antibiotic overuse and the corresponding rise in bacterial resistance necessitates an urgent shift towards an antibiotic-free approach to antibacterial treatment. The quest for antimicrobial efficacy while accelerating wound healing without antibiotic treatment have emerged as innovative strategies in skin wound treatment. Here, a dual-function hydrogel with antimicrobial and enhanced tissue-healing properties was developed by utilizing cyclodextrin, ferrocene, polyethyleneimine (PEI), and Bletilla striata polysaccharide (BSP), through multiple non-covalent interactions, which can intelligently release BSP by recognizing the wound inflammatory microenvironment through the cyclodextrin-ferrocene unit. Moreover, the porosity (65 % - 85 %), Young's modulus (400 KPa - 140 KPa), and DPPH scavenge rate (18 % - 40 %) of the hydrogel are modulated by varying the BSP content. The hydrogel exhibits outstanding antibacterial properties (98.3 % reduction of Escherichia coli observed after exposure to HTFC@BSP-20 for 24 h) and favorable biocompatibility. Furthermore, in a rat full-thickness skin wound model, the dual-function hydrogel significantly accelerates wound healing, increased CD31 expression promotes vascular regeneration, reduced TNF-α express and inhibited the inflammation. This multifunctional ROS responsive hydrogel provides a new perspective for antibiotics-free treatment of skin injuries.

Fabrication and development of biogenic selenium nanoparticles incorporated alginate hydrogel wound care material: a pre-clinical study

ABSTRACT In this study, we attempted to make a nanocomposite wound dressing that was both interactive and bioactive. In order to characterize the biogenic selenium nanoparticles, characterization techniques such as SEM, EDX, DLS, Zetasizer, FTIR, and XRD were utilized. The XRD results showed that the peaks located at around 2θ = 23.9°, 30.1°, 41.6°, 44.1°, and 52.9° that are corresponded to the (100), (101), (110), (102), and (201) reflections of the pure hexagonal phase of selenium crystals. The results of zeta potential measurement showed that the biosynthesized SeNPs have a zeta potential of around −27.5 mV. Studies conducted on animals using a full-thickness wound model of the rat’s skin showed that the wound dressing was able to speed up the natural process of wound healing. Based on the findings, it was determined that the wound dressing has the potential to serve as an effective wound dressing and healing material.

Design And Characterization Of Regenerative Potential In Full Thickness Burn Wound Model

Hydrogel is a three-dimensional network of interconnecting polymers that is crosslinked and consists of hydrophilic polymers that can absorb and endure water. Because it mimics the extracellular matrix (ECM), the hydrogel has found widespread use in pharmacological and biological applications. Many types of wound dressings are based on hydrogels due to its many advantages. These dressings include Coseal, Tegaderm, Algisite, and Evicel. Notwithstanding their exceptional ability to cure wounds, they have many drawbacks, including expensive expenses, unfavourable storage conditions, and inadequate mechanical protection for the wound. As we have come to realise the need for dressings with greater performance qualities (e.g., antimicrobial, biodegradable, responsive, and injectable), the field of wound dressings has attracted an increasing amount of interest. The purpose of this work is to evaluate the hydrogel loaded with 7, 8-Dihydroxy flavone's healing capabilities in a full-thickness burn wound model.

Evaluation of Full Thickness Wounds Following Application of a Visco-Liquid Hemostat in a Swine Model.

Wound healing is a complex dynamic biomechanical process as the body attempts to restore the integrity of traumatized or devitalized tissues. There are four stages of wound of healing that begins with hemostasis followed by inflammation, proliferation and finally weeks later wound remodeling. Full thickness wounds usually are covered with a dressing material after hemostasis, which allows for controlled hydration. We investigated the potential of a visco-liquid hemostat, polyhedral oligomeric silsesquioxane (POSS), for providing hemostasis and to maintain a microenvironment in the wound bed that would maintain moisture content and promote early re-epithelialization. We hypothesized that the hemostatic agent POSS if left in the wound bed would maintain a protective barrier and accelerate wound healing similar to using saline to irrigate the wound to keep the wound moist. We compared the early phase of wound repair (3-7 days) in a porcine full thickness wound model to evaluate the efficacy of the material. Biopsies were taken after 3 and 7 days to determine the acute response of the POSS hemostat or saline on inflammation, cell migration, concentrations of metalloproteinase (MMPs), and tissue inhibitors of metalloproteinase (TIMPs). Accelerated healing was observed in POSS treated wounds by changes in wound contraction, keratinocyte migration, and development of granulation tissue in comparison to saline treated wounds. Increased concentrations at day 3 of MMP-2, MMP-3, and in MMP-1 at day 7 in POSS treated wounds compared to saline coincide with keratinocyte migration observed in the tissue histology and changes in wound contraction. Tissue concentrations of TIMP-1 and TIMP-2 in POSS treated wounds appear to coordinate the sequence of MMP events in the healing tissue. Matrix metalloproteinase-13, a marker for tissue remodeling, was not upregulated in the early wound healing cascade in either POSS or saline treated wounds at 3 or 7 days. Overall, the data suggests POSS treatment contributed to enhanced early cell migration and wound closure compared to saline treatment.

The stress-responsive gene ATF3 drives fibroblast activation and collagen production through transcriptionally activating TGF-β receptor Ⅱ in skin wound healing

Skin wound is an emerging health challenge on account of the high-frequency trauma, surgery and chronic refractory ulcer. Further study on the disease biology will help to develop new effective approaches for wound healing. Here, we identified a wound-stress responsive gene, activating transcription factor 3 (ATF3), and then investigated its biological action and mechanism in wound healing. In the full-thickness skin wound model, ATF3 was found to promote fibroblast activation and collagen production, resulted in accelerated wound healing. Mechanically, ATF3 transcriptionally activated TGF-β receptor Ⅱ via directly binding to its specific promoter motif, followed by the enhanced TGF-β/Smad pathway in fibroblasts. Moreover, the increased ATF3 upon skin injury was partly resulted from hypoxia stimulation with Hif-1α dependent manner. Altogether, this work gives novel insights into the biology and mechanism of stress-responsive gene ATF3 in wound healing, and provides a potential therapeutic target for treatment.

Trinitroglycerin-loaded chitosan nanogels accelerate angiogenesis in wound healing process

Trinitroglycerin (TNG) with remarkable angiogenic, antibacterial, and antioxidative activity is a promising candidate to govern wound healing capacity. However, its clinical administration is limited due to associated complications and NO short half-life. In the current study, TNG-loaded chitosan nanogels (TNG-Ngs) were examined in-vitro and in-vivo to gain insight into their clinical application. We prepared TNG-Ngs and characterized their physiochemical properties. The potential of TNG-Ngs was assessed using biocompatibility, scratch assay, and a full-thickness skin wounds model, followed by histopathological and immunohistochemistry examinations. TNG-Ngs particle size 96 ± 18 and definite size distribution histogram. The loading capacity (LC) and encapsulation efficiency (EE) of prepared TNG-Ngs were 70.2 % and 2.1 %, respectively. The TNG-Ngs samples showed enhanced migration of HUVECs with no apparent cytotoxicity. The topical use of TNG-Ngs200 on the wounds revealed a complete wound closure ratio, skin component formation, less scar width, remarkable granulation tissue, promoted collagen deposition, and enhanced the relative mean density of α-SMA and CD31. TNG-Ngs accelerated wound healing by promoting collagen deposition and angiogenic activity, as well as reducing inflammation. The findings indicated that TNG-Ngs is expected to be well vascularized in the wound area and to be more effective in topical therapy.

Cost-effective and natural-inspired lotus root/GelMA scaffolds enhanced wound healing via ROS scavenging, angiogenesis and reepithelialization

Skin wounds, prevalent and fraught with complications, significantly impact individuals and society. Wound healing encounters numerous obstacles, such as excessive reactive oxygen species (ROS) production and impaired angiogenesis, thus promoting the development of chronic wound. Traditional clinical interventions like hemostasis, debridement, and surgery face considerable challenges, including the risk of secondary infections. While therapies designed to scavenge excess ROS and enhance proangiogenic properties have shown effectiveness in wound healing, their clinical adoption is hindered by high costs, complex manufacturing processes, and the potential for allergic reactions. Lotus root, distinguished by its natural micro and macro porous architecture, exhibits significant promise as a tissue engineering scaffold. This study introduced a novel scaffold based on hybridization of lotus root-inspired and Gelatin Methacryloyl (GelMA), verified with satisfactory physicochemical properties, biocompatibility, antioxidative capabilities and proangiogenic abilities. In vivo tests employing a full-thickness wound model revealed that these scaffolds notably enhanced micro vessel formation and collagen remodeling within the wound bed, thus accelerating the healing process. Given the straightforward accessibility of lotus roots and the cost-effective production of the scaffolds, the novel scaffolds with ROS scavenging, pro-angiogenesis and re-epithelialization abilities are anticipated to have clinical applicability for various chronic wounds.

Botulinum toxin type A inhibits the formation of hypertrophic scar through the JAK2/STAT3 pathway.

Hypertrophic scar (HS) is a fibrous proliferative disorder that occurs in the dermis after skin injury. Studies have confirmed that Botulinum toxin type A (BTA) is effective in scar prevention and treatment. However, the specific mechanism remains uncertain. Hypertrophic scar fibroblasts (HSFs) and normal skin fibroblasts (NSFs) from the skin tissues of HS patients were isolated and cultured. Western blot analysis was conducted to measure the expression of JAK2/STAT3 pathway-related proteins. HSFs were treated with the JAK2 inhibitor (AG490) or agonist (C-A1). The CCK-8 assay, EdU staining, scratch-wound assay and transwell assay were used to examine the biological properties of HSFs. Western blot, immunofluorescence, and Sirius red staining were used to assess the fibrosis of HSFs. Additionally, a mouse full-thickness wound model was constructed to investigate the role of BTA in wound healing. The results showed that the JAK2 and STAT3 phosphorylation levels were markedly increased in HS tissues and HSFs. AG490 treatment reduced cell viability, proliferation and migration capacity, and inhibited the fibrosis of HSFs, whereas C-A1 treatment had the opposite effect. BTA treatment inhibited the JAK2/STAT3 pathway. BTA reduced cell viability, proliferation and migration ability, and inhibited the fibrosis of HSFs, while C-A1 intervention weakened the impact of BTA. Meanwhile, BTA promoted wound healing and reduced collagen deposition in vivo. In conclusion, BTA inhibited the JAK2/STAT3 pathway, which in turn hindered the proliferation, migration and fibrosis of HSFs, and promoted wound healing in mice.

Black Phosphorus Nanosheets-Based Hydrogel for Efficient Bacterial Inhibition and Accelerating Wound Healing.

With the swift evolution of multidrug-resistant bacteria resulting from the intense and inappropriate use of antibiotics, there is a pressing need for innovative solutions. In this study, a thermosensitive hydrogel was developed for efficient bacterial inhibition and promotion of wound healing. The antibacterial chitosan (CS) thermosensitive hydrogel, cross-linked with two-dimensional photothermal nanomaterial black phosphorus (BP) nanosheets through electrostatic interactions, effectively encapsulates and sustains the release of angiogenic drug deferoxamine mesylate (DFO). This facilitates the acceleration of re-epithelialization and neovascularization by enhancing cell migration and proliferation. Following near-infrared (NIR) treatment, this hydrogel demonstrates rapid eradication of the most common multidrug-resistant bacteria encountered in clinical settings, achieved through physical disruption of bacterial membranes and photothermal therapies. Noteworthy is the significant upregulation of IL-19 expression via STAT3 signaling pathways by the BP/CS-DFO hydrogel in a full-thickness wound model. This results in the polarization of the anti-inflammatory M2 macrophage phenotype, altering the microenvironment to a pro-healing state and enhancing extracellular matrix deposition and blood vessel formation. In conclusion, the BP/CS-DFO hydrogel shows immense promise as a potential clinical candidate for wound healing and antimicrobial therapy. Its innovative design and multifunctional capabilities position it as a valuable asset in combating antibiotic resistance and enhancing efficiency in wound healing.

Development and characterization of contraction-suppressed full-thickness skin wound model in rabbits

The wound healing process in rodents (rats and mice) and lagomorphs (rabbits) predominantly relies on wound contraction rather than re-epithelialization and granulation tissue formation. As a result, existing laboratory animal models for wound healing often fail to mimic human wound healing mechanisms accurately. This study introduces a standardized rabbit model with superior translational potential for skin wound healing research. Two full-thickness dermal wounds were created on the posterior dorsal surface of each rabbit using a standard 2 ×2 cm² template. One of these wounds was randomly selected to be treated as a contraction-suppressed wound by applying a transparent adhesive elastic bandage. At the same time, the other was retained as a standard full-thickness wound. Wound contraction was measured on 7, 14, 21, 28, and 35 days. Histomorphological evaluation was done on day 35 to evaluate the quality of wound healing. The findings indicate that transparent adhesive elastic bandage prolonged the wound healing time and suppressed wound contraction in rabbits. In addition, the healed contraction-suppressed full-thickness wounds had denser and thicker collagen fibers than the healed standard full-thickness wounds, indicating better collagen fiber deposition. Our model achieved a 100 % success rate in maintaining the transparent adhesive elastic bandage in the rabbits. Therefore, we have developed a simple, non-invasive, cost-effective method for preventing wound contraction. Further studies are required to establish the utility of this model for studying wound healing mechanisms and evaluating therapeutic interventions.

Enhanced healing of burn wounds by multifunctional alginate-chitosan hydrogel enclosing silymarin and zinc ‎oxide ‎nanoparticles

Multifunctional wound dressings have been applied for burn injuries to avoid complications and promote tissue regeneration. In the present study, we fabricated a natural alginate-chitosan hydrogel comprising silymarin and green-synthesized zinc ‎oxide ‎nanoparticles (ZnO NPs). Then, the physicochemical attributes of ZnO NPs and loaded hydrogels were analyzed. Afterward, wound healing efficacy was evaluated in a rat model of full-thickness dermal burn wounds. The findings indicated that ZnO NPs were synthesized via reduction with phytochemicals from Elettaria cardamomum seeds extract. The microscopic images exhibited fairly spherical ZnO NPs (35-45nm), and elemental analysis verified the relevant composition. The hydrogel, containing silymarin and biosynthesized ZnO NPs, displayed a uniform appearance, smooth surfaces, and a porous structure. Moreover, infrared spectroscopy ‎identified functional groups, confirming the successful loading without adverse interactions. The obtained hydrogel exhibited great water absorption, high porosity, sustainable degradation for several days, and enhanced antioxidant capability of the combined loaded component. In vivo studies revealed faster and superior wound healing, achieving nearly complete closure by day 21. Histopathology confirmed improved cell growth, tissue regeneration, collagen deposition, and neovascularization. It is believed that this multifunctional hydrogel-based wound dressing can be applied for effective burn wound treatment.

Injectable immunoregulatory hydrogels sequentially drive phenotypic polarization of macrophages for infected wound healing

Regulating macrophage phenotypes to reconcile the conflict between bacterial suppression and tissue regeneration is ideal for treating infectious skin wounds. Here, an injectable immunoregulatory hydrogel (SrmE20) that sequentially drives macrophage phenotypic polarization (M0 to M1, then to M2) was constructed by integrating anti-inflammatory components and proinflammatory solvents. In vitro experiments demonstrated that the proinflammatory solvent ethanol stabilized the hydrogel structure, maintained the phenolic hydroxyl group activity, and achieved macrophages' proinflammatory transition (M0 to M1) to enhance antibacterial effects. With ethanol depletion, the hydrogel's cations and phenolic hydroxyl groups synergistically regulated macrophages' anti-inflammatory transition (M1 to M2) to initiate regeneration. In the anti-contraction full-thickness wound model with infection, this hydrogel effectively eliminated bacteria and even achieved anti-inflammatory M2 macrophage accumulation at three days post-surgery, accelerated angiogenesis and collagen deposition. By sequentially driving macrophage phenotypic polarization, this injectable immunoregulatory hydrogel will bring new guidance for the care and treatment of infected wounds.

A facile strategy to fabricate stretchable, low hysteresis and adhesive zwitterionic elastomers by concentration-induced polymerization for wound healing

Developing high-efficient wound dressing with a combination of good mechanical toughness, conformal adhesion and multiple functions is important in clinical application yet remains challenge. Herein, a multi-functional zwitterionic elastomer (TASM) was developed by directly evaporating the uniform precursor containing zwitterionic monomer 3-[Dimethyl-[2-(2-methylprop-2-enoyloxy) ethyl] azaniumyl] propane-1-sulfonate (SBMA), α-thioctic acid (TA) and [2-(methacryloyloxy) ethyl] trimethyl ammonium chloride (METAC). It is interesting to find that the originally immiscible SBMA could dissolve well in ethanol with the assistance of TA, while some other zwitterionic still cannot. The underlying reason is revealed through Flory-Huggins model that the mixture of SBMA and TA exhibit a very low mixing free energy, making them successfully dissolve in ethanol. The obtained TASM elastomer exhibited good mechanical performance, robust adhesion, self-healing ability, along with wound monitoring potential. Besides, the elastomer also showed excellent biocompatibilities and efficient anti-bacterial capability. Furthermore, the elastomer worked well in promoting wound healing in both of full-thickness wound and incisions models. Specifically, in the incision model, the elastomer treatment can replace suturing treatment thanks to the strong adhesion, showing great advantages as wound dressing materials. This work could offer new insights into the preparation of PolyTA systems and promote their functionalization and applications.

Development of mADM-collagen wound dressings for mimicking native skin architecture to enhance skin wound healing

Acellular dermal matrix (ADM) is one of the most promising scaffold materials due to its ability to retain natural extracellular matrix structure. Micronized acellular dermal matrix (mADM) was prepared with no intact cell nuclei and preserved growth factors by High Hydrostatic Pressure (HHP) approach. And mADM-collagen wound dressings were developed with different proportion of type I collagen and recombinant humanized type III collagen. The porous structure of the mADM-collagen wound dressings made them a good candidate for preventing excessive fluid accumulation, while the collagens with gel-like texture combined with mADM powder to form pasty texture wound dressing, which preserving the moisture at the wound site. Moreover, the paste texture of the mADM-collagen wound dressing was easy to reshape to conform any wound shapes and body contours. Furthermore, the resulted mADM-collagen wound dressings showed good biocompatibility by supporting fibroblasts adhesion and proliferation in vitro. Subsequently, a murine model of full-thickness skin wounds was employed to assess its effects on wound healing. Notably, mADM-75% Col-I exhibited superior effects throughout the wound healing process, specifically it promoted neovascularization, skin appendage growth and new skin regeneration. This formulation closely mimicked the collagen ratio found in healthy skin, facilitating the favorable wound repair. These results indicated the superior performance of this mADM-collagen wound dressing providing an optimal environment for wound healing.Graphical

Developing multifunctional pectin-based hydrogel for wound dressing: In silico, in vitro and in vivo evaluation

Multifunctional hydrogel wound dressing with high hemostatic, antioxidant, and self-healing activity is desirable in clinical applications. In this contribution, we developed two distinct hydrogel formulations, namely PZ and PTBA, by employing low methoxyl pectin (P), zeolite, or 2-thiobarbituric acid (TBA) for sustained release of procaine (PC) in a controlled manner up to 40 h. These hydrogel systems (PZ and PTBA) utilize dynamic reversible hydrogen bonds between the components and a metal coordination bond between carboxyl acid groups of pectin chains and Ca2+ to confer self-healing properties, as demonstrated by molecular dynamics (MD) and rheological analyses. Moreover, PZ and PTBA hydrogels possess superior antioxidant, hemostasis, biocompatibility, and antibacterial activities. The data from the mouse skin incision model and infected full-thickness skin wound model demonstrated the highest wound closure rate (wound closure area per day) was achieved by the PZ (4.72) and PTBA (4.62) groups on day 21, which was better than the control (4.2) and Kaltostat groups (4.05) (p < 0.05). PZ and PTBA’s effectiveness in wound closure and acceleration of the wound healing process, highlighting its significant potential in wound management.