Skin Wound Healing In Rats Research Articles

The Effect of Topical Curcumin Extract on Fibroblast Count and Collagen Density as an Indicator on Accelerating Clean Wound Healing Process: A Study on Wistar Rats

A factor that plays an important role in the process of wound healing is fibroblast, where fibroblasts can trigger the formation of collagen. Turmeric (Curcuma longa) containing curcumin and volatile oil is believed to accelerate fibroblast proliferation and collagen synthesis. This study compared the effectiveness of curcumin extract topical and tulle in the acceleration the process of wound healing in rat skin. This was an experimental study using Rattus novergicus. rats were divided into four groups: group of wounds that treat with carbomer, NaCl 0.9%, tulle and curcumin extract topical, then they were compared by the fibroblast count and collagen density. In this study, there were significant differences in the number of fibroblasts among the four groups (p = 0.034). We found that mean fibroblast count in group of wounds treated with curcumin extract topical was higher than that treated with tulle, and we obtained p = 0.045. There was no difference in collagen density score between groups of wounds treated with curcumin extract topical and tulle. There was a significant difference of fibroblast count in curcumin extract topical group compared to tulle group. However, there was no significant difference in collagen density score between both of them. How to Cite this Article Pubmed Style Erick Berto Yahya, Ariandi Setiawan, Marjono Dwi Wibowo, Edwin Danardono. Effect of Topical Curcumin Extract on Fibroblast Count and Collagen Density as an Indicator on Accelerating Clean Wound Healing Process: A Study on Wistar Rats. SRP. 2020; 11(5): 567-570. doi:10.31838/srp.2020.5.74 Web Style Erick Berto Yahya, Ariandi Setiawan, Marjono Dwi Wibowo, Edwin Danardono. Effect of Topical Curcumin Extract on Fibroblast Count and Collagen Density as an Indicator on Accelerating Clean Wound Healing Process: A Study on Wistar Rats. http://www.sysrevpharm.org/?mno=112417 [Access: March 28, 2021]. doi:10.31838/srp.2020.5.74 AMA (American Medical Association) Style Erick Berto Yahya, Ariandi Setiawan, Marjono Dwi Wibowo, Edwin Danardono. Effect of Topical Curcumin Extract on Fibroblast Count and Collagen Density as an Indicator on Accelerating Clean Wound Healing Process: A Study on Wistar Rats. SRP. 2020; 11(5): 567-570. doi:10.31838/srp.2020.5.74 Vancouver/ICMJE Style Erick Berto Yahya, Ariandi Setiawan, Marjono Dwi Wibowo, Edwin Danardono. Effect of Topical Curcumin Extract on Fibroblast Count and Collagen Density as an Indicator on Accelerating Clean Wound Healing Process: A Study on Wistar Rats. SRP. (2020), [cited March 28, 2021]; 11(5): 567-570. doi:10.31838/srp.2020.5.74 Harvard Style Erick Berto Yahya, Ariandi Setiawan, Marjono Dwi Wibowo, Edwin Danardono (2020) Effect of Topical Curcumin Extract on Fibroblast Count and Collagen Density as an Indicator on Accelerating Clean Wound Healing Process: A Study on Wistar Rats. SRP, 11 (5), 567-570. doi:10.31838/srp.2020.5.74 Turabian Style Erick Berto Yahya, Ariandi Setiawan, Marjono Dwi Wibowo, Edwin Danardono. 2020. Effect of Topical Curcumin Extract on Fibroblast Count and Collagen Density as an Indicator on Accelerating Clean Wound Healing Process: A Study on Wistar Reviews in Pharmacy, 11 (5), 567-570. doi:10.31838/srp.2020.5.74 Chicago Style Erick Berto Yahya, Ariandi Setiawan, Marjono Dwi Wibowo, Edwin Danardono. The Effect of Topical Curcumin Extract on Fibroblast Count and Collagen Density as an Indicator on Accelerating Clean Wound Healing Process: A Study on Wistar Rats. Systematic Reviews in Pharmacy 11 (2020), 567-570. doi:10.31838/srp.2020.5.74 MLA (The Modern Language Association) Style Erick Berto Yahya, Ariandi Setiawan, Marjono Dwi Wibowo, Edwin Danardono. The Effect of Topical Curcumin Extract on Fibroblast Count and Collagen Density as an Indicator on Accelerating Clean Wound Healing Process: A Study on Wistar Rats. Systematic Reviews in Pharmacy 11.5 (2020), 567-570. Print. doi:10.31838/srp.2020.5.74 APA (American Psychological Association) Style Erick Berto Yahya, Ariandi Setiawan, Marjono Dwi Wibowo, Edwin Danardono (2020) Effect of Topical Curcumin Extract on Fibroblast Count and Collagen Density as an Indicator on Accelerating Clean Wound Healing Process: A Study on Wistar Reviews in Pharmacy, 11 (5), 567-570. doi:10.31838/srp.2020.5.74

Evaluation of the wound healing potential of Sophora alopecuroides in SD rat's skin

Ethnopharmacological relevanceSophora alopecuroides Linn. (Leguminosae) has been largely used in traditional folk medicine in China as an anti-inflammatory agent and to treat various skin wounds, including sore furunculosis and ulcer (a common type of non-healing wound). The present study aimed to evaluate the effects of S. alopecuroides gel on skin wound healing in rats. Materials and methodsWhen the rats were anesthetized, full-thickness skin wound was performed on dorsal area by using biopsy punch with 8 mm diameter. Then, wounds received treatment with different doses of S. alopecuroides gel (1.25%, 2.5% and 5%, w/w) once a day with the gel base used as vehicle control and rb-FGF as positive control. Every five animals were sacrificed after 7, 12 days after surgery for histopathology and relevant biochemical indexes analysis. Besides, after RAW 264.7 cells exposure to LPS (1 μg/ml) with or without total extract (25 and 50 μg/ml) for 24 h, the culture supernatant was used for detection of IL-1β and TNF-α levels using ELISA kits and the protein lysate for western blot analysis. ResultsA remarkable wound closure was observed after administration with 5% S. alopecuroides gel with the wound area of 30% and 8.5% as compared to 42% and 19% in the control group on day 7 and 12, respectively. Histological and immunostaining analysis for the wound tissues also revealed that S. alopecuroides promoted the growth of granulation tissue, collagen deposition, cell proliferation and angiogenesis. Meanwhile, it was able to ameliorate inflammatory response and promote the production of TGF-β. In addition, we also demonstrated that S. alopecuroides inhibited the release of inflammatory mediators and expression of iNOS as well as up-regulated the expression of Arg-1 in LPS-triggered RAW 264.7 cells. ConclusionsThe present study confirmed that S. alopecuroides had a great potential for accelerated wound healing by regulating the over expression of inflammatory response for the first time and provided theoretical basis for the traditional use. It can be used as candidate drug for the treantment of chronic non-healing wounds.

Effect of snail mucus on angiogenesis during wound healing

Background: Angiogenesis is the process through which new blood vessels are formed from existing ones. This process plays an important role in supplying the oxygen and nutrients needed for cellular metabolism and eliminating cell debris during wound healing. Snail mucus can bind to several factors that stimulate angiogenesis, including vascular endothelial growth factor, platelet-derived growth factor, and fibroblast growth factor. The aim of this study is to observe changes in angiogenesis during the healing of wounds topically applied with snail mucus. Methods: Punch biopsy was performed on the back of male Wistar rats to obtain four wounds, and different concentrations of snail mucus were applied to each of these wounds. The animals were sacrificed on days 2, 4, and 7 to observe the extent of angiogenesis during wound healing by microscopy. Results: Two-way ANOVA showed differences in number of blood vessels formed (p = 0.00) and day of observation (p = 0.00) between groups. Post hoc Tukey’s HSD test showed that 24% snail mucus treatment does not significantly affect wound healing (p = 0.488); by contrast, treatment with 48% and 96% snail mucus demonstrated significant effects on angiogenesis (p = 0.01). Spearman’s test showed interactive effects between snail mucus concentration and day of observation on the extent of angiogenesis (p = 0.001, R = 0.946). Conclusion: Topical application of snail mucus gel can increase angiogenesis during wound healing in Wistar rat skin.

The Combined Effect of Photobiomodulation and Curcumin on Acute Skin Wound Healing in Rats.

Introduction: Abnormal wound repair is a cause for considerable expense, as well as patient morbidity and mortality. Here, we investigated the combined impact of photobiomodulation (PBM) and curcumin on a rat experimental model of an acute skin wound. Methods: A round full-thickness wound was created on the back of each rat. We divided the rats into the following four groups. Group one was the control group. Group two received pulse wave (PW) PBM at a dose of 890 nm, 80 Hz, and 0.2 J/cm2. Group 3 received 40 mg/kg curcumin by gastric gavage and group 4 were treated with PWPBM + curcumin. We measured the wound area on days 4, 7, and 15, and performed microbiological and tensiometric examinations. Results: There was markedly improved wound contraction in the curcumin (7.5 ± 0.57; P =0.000), PBM (8.5 ± 1.2; P =0.000), and PBM + curcumin (14.5 ± 4.3; P =0.002) groups relative to the control group (25 ± 6). PBM (100 ± 7.3; P =0.005), and PBM + curcumin (98 ± 6; P =0.005) groups meaningfully improved tensile strength relative to the control group (61 ± 8.2). On day 15, the PBM (10 ± 5; P =0.000), curcumin (14 ± 4.5, P =0.000), and PBM + curcumin (27.3 ± 8.3; P =0.000) groups meaningfully decreased microbial flora relative to the control group (95 ± 6). Conclusion: We concluded that the PBM and PBM + curcumin groups meaningfully accelerated wound healing of the acute skin wound in the rats. The results of the PBM group were statistically more effective than the curcumin alone and PBM + curcumin-treated groups.

Alginate, gelatin, and carboxymethyl cellulose coated nonwoven fabrics containing antimicrobial AgNPs for skin wound healing in rats

Nonwoven fabrics containing silver nanoparticles (AgNPs) are widely utilized to assist management of infected wounds and those at risk of infection. However, such materials have varied responses due to their chemical nature. Herein we investigated the correlation between the concentration of AgNPs taken up by nonwoven viscose material and antibacterial activity in a simulated wound fluid model against two bacterial models (i.e., Escherichia coli and Staphylococcus aureus). Thereafter, the developed nonwoven viscose containing AgNPs were independently coated with two polyacid carbohydrate polymers (i.e., carboxymethyl chitosan (CMCs), alginate (ALG)), and gelatin (GEL) protein in order to study their influence on the physical and biological attributes in vitro and in vivo. Intensive characterizations were utilized to monitor the physicochemical features of the developed nonwoven viscose. The results demonstrated that higher concentrations of AgNPs were taken up by viscose fabric whilewhile increasing AgNPs in the colloidal solution during padding process. Overall, the treated nonwoven fabric with and without polymers' coatings showed remarkable antibacterial activity against two bacterial models in vitro. As well as they achieved high and speed wound recovery in rats which was almost similar to commercial dermazin treatment. Therefore, it validates excellent nonwoven dressing clinically relevant to the wound type and condition.

Ecballium elaterium extract reduces fibrosis during wound healing in rats

We explored the effects of subcutaneously injected Ecballium elaterium (L) A. Rich. (EE) extract on skin wound-healing in rats, as well as the effects on the liver and pancreas. Twenty-eight rats were divided into two groups of 14 each: a saline control group (S) and an EE group. Both groups were divided into two subgroups according to the day of sacrifice (S-7 and S-14, and EE-7 and EE-14). All animals received 2.5 cm skin incisions followed by subcutaneous injections of either saline or 2.5 mg/kg EE per margin (5 mg/kg in total). The S and EE groups were compared in terms of the severity and type of local and neighbouring inflammation, vascularization, fibrosis and effects on the liver and pancreas. In addition, apoptosis and vascularity between S and EE groups were compared immunohistochemically with caspase-3 and cd-34 antibodies. There was no significant difference between the staining rates of caspase-3 and cd-34 in the immunohistochemical assay between the S and E groups. Subcutaneous EE was not toxic to the pancreas or liver; the EE-14 group exhibited less fibrosis than the S-14 group. Therefore, it can contribute to the proper closure of the lesion by reducing fibrosis during wound healing.

Downregulation of miR‑27b promotes skin wound healing in a rat model of scald burn by promoting fibroblast proliferation

The aim of the present study was to investigate the effect and mechanism of action of microRNA (miR)-27b on skin wound healing in rats with deep second-degree scald burns and in BJ human skin fibroblast cells. Rat models with deep second-degree scald burns were constructed and injected with miR-27b mimics and inhibitors at the wound site daily for 21 days. Healing of burned skin tissues was observed at 0, 3, 7, 14 and 21 days following modeling. H&E and Masson staining were used to observe the pathological structure and degree of collagen fibers in the burned skin tissues. The effects of miR-27b on BJ cell proliferation and migration were determined by MTT and scratch assays. Matrix metalloproteinase-1 (MMP-1), α-smooth muscle actin (α-SMA), collagen I and collagen III expression in rat skin tissues and BJ cells were measured via reverse transcription-quantitative PCR and western blot analysis. The results of the in vivo experiments demonstrated that miR-27b inhibition accelerated scalded skin healing and induced fibroblast growth. Furthermore, the in vitro experiments revealed that miR-27b inhibition increased BJ cell proliferation and migration. Furthermore, miR-27b inhibition upregulated MMP-1, α-SMA, collagen I and collagen III expression in the skin tissues and cells, while the overexpression of miR-27b demonstrated the opposite effect. In conclusion, the results of the present study revealed that miR-27b inhibition increased fibroblast proliferation, thereby accelerating scald wound healing in rats.

From Inflammation to Cutaneous Repair: Topical Application of Lupeol Improves Skin Wound Healing in Rats by Modulating the Cytokine Levels, NF-κB, Ki-67, Growth Factor Expression, and Distribution of Collagen Fibers.

Skin wound healing is a highly complex event that involves different mediators at the cellular and molecular level. Lupeol has been reported to possess different biological activities, such as anti-inflammatory, antioxidant, antidiabetic, and in vitro wound healing properties, which motivated us to proceed with in vivo studies. We aimed to investigate the wound healing effect of lupeol-based cream for 3, 7, and 14 days. Wound excisions were induced on the thoraco-lumbar region of rats and topically treated immediately after injury induction. Macroscopic, histopathological, and immunohistochemical analyses were performed. Cytokine levels were measured by ELISA and gene expression was evaluated by real-time RT-qPCR. Our results showed a strong wound-healing effect of lupeol-based cream after 7 and 14 days. Lupeol treatment caused a reduction in proinflammatory cytokines (TNF-a, IL-1β, and IL-6) and gene and protein NF-κB expression, and positively altered IL-10 levels, showing anti-inflammatory effects in the three treatment periods. Lupeol treatment showed involvement in the proliferative phase by stimulating the formation of new blood vessels, increasing the immunostaining of Ki-67 and gene expression, and immunolabeling of vascular endothelial growth factor (VEGF) and epidermal growth factor (EGF), and increasing gene expression of transforming growth factor beta-1 (TGF-β1) after seven days of treatment. Lupeol was also involved in the tissue regeneration phase by increasing the synthesis of collagen fibers noted in the three treatment periods analyzed. Our findings suggest that lupeol may serve as a novel therapeutic option to treat cutaneous wounds by regulating mechanisms involved in the inflammatory, proliferative, and tissue-remodeling phases.

Sustained release of human platelet lysate growth factors by thermosensitive hydroxybutyl chitosan hydrogel promotes skin wound healing in rats.

This study evaluated the effect of thermosensitive hydroxybutyl chitosan (HBC) hydrogel loaded with human platelet lysate (hPL) on skin wound healing in rats. hPLs were generated by freeze-thaw method of platelet-rich plasma from healthy donors. Successful grafting of hydroxybutyl group to chitosan molecular chain to obtain HBC hydrogel was confirmed by Fourier-transform infrared spectroscopy. HBC/hPL was prepared by combining 10% (vol/vol) hPL with HBC solution. Surface morphologies were determined by Scanning Electron Microscopy, rheological properties were measured by rheometer, and sustained release of factors from HBC/hPL was measured by enzyme-linked immunoassay. We evaluated the in vitro effect of HBC/hPL on human umbilical cord vein endothelial cell (HUVEC) proliferation, migration, and tube formation. The effect of growth factors released from HBC/hPL in promoting skin wound healing was evaluated by gross observation, histology, immunohistochemistry, and immunofluorescence in vivo. Rheological analyses indicated the gelation temperatures of HBC and HBC/hPL were 17 and 14°C, respectively. ELISA showed sustained release of human platelet-derived growth factor, basic fibroblast growth factor, and transforming growth factor-β1 from HBC/hPL hydrogel. In vitro studies revealed HBC/hPL promoted greater levels of HUVECs proliferation, migration, and tube formation than the HBC and control groups. In vivo studies showed better wound healing, greater amounts of newly formed collagen, as well as neovascular and neo-epidermis markers in the wound site of HBC/hPL-treated group compared to the HBC and control groups. HBC/hPL is a promising potential therapeutic agent for promoting skin wound healing via the sustained release of growth factors.

EFFECTS OF PROBIOTICS SUPPLEMENTATION ON SKIN WOUND HEALING IN DIABETIC RATS.

ABSTRACT Background: Chronic wounds in patients with Diabetes Mellitus often become incurable due to prolonged and excessive production of inflammatory cytokines. The use of probiotics modifies the intestinal microbiota and modulates inflammatory reactions. Aim: To evaluate the influence of perioperative supplementation with probiotics in the cutaneous healing process in diabetic rats. Methods: Forty-six rats were divided into four groups (C3, P3, C10, P10) according to the treatment (P=probiotic or C=control, both orally administered) and day of euthanasia, 3rd or 10th postoperative days. All rats were induced to Diabetes Mellitus 72 h before starting the experiment with alloxan. Supplementation was initiated five days before the incision and maintained until euthanasia. Scalpel incision was guided by a 2x2 cm mold and the wounds were left to heal per second-intention. The wounds were digitally measured. Collagen densitometry was done with Picrosirius Red staining. Histological parameters were analyzed by staining by H&E. Results: The contraction of the wound was faster in the P10 group which resulted in a smaller scar area (p=0.011). There was an increase in type I collagen deposition from the 3rd to the 10th postoperative day in the probiotic groups (p=0.016), which did not occur in the control group (p=0.487). The histological analysis showed a better degree of healing in the P10 group (p=0.005), with fewer polymorphonuclear (p<0.001) and more neovessels (p=0.001). Conclusions: Perioperative supplementation of probiotics stimulates skin wound healing in diabetic rats, possibly due to attenuation of the inflammatory response and increased neovascularization and type I collagen deposition.

Human mesenchymal stem cells-conditioned medium improves diabetic wound healing mainly through modulating fibroblast behaviors.

Fibroblast plays a key role in wound healing, and the advantages of mesenchymal stem cells (MSC) secretome in wound healing have previously been reported. In the present study, we investigated the impact of human bone marrow MSC-conditioned media (CM) on skin wound healing in diabetic rats and found that some improvements occurred mainly through fibroblast functions. Then, we scrutinized the impact of MSC-CM treatment on fibroblast cellular behavior by culturing human dermal fibroblasts (HDFs) in a high-glucose (HG) medium, as an in vitro diabetic model. In vivo findings revealed significant improvements in some healing kinetics of diabetic wound which received MSC-CM. Particularly, MSC-CM-treated diabetic wounds reached considerably higher percentages of wound closure. Also, the granulation tissue of these wound had less pronounced inflammatory response, better tissue remodeling, and more vascularization compared with non-treated diabetic ones. Gene expression analyses indicated that MSC-CM treatment leads to upregulation of epidermal growth factor (EGF) and basic fibroblast growth factor (bFGF) genes. In addition, a significantly higher cell viability/proliferation, migration, and bFGF gene expression were observed when MSC-CM was used to treat HDFs in HG culture media. Based on these findings, it is suggested that MSC-CM could promote wound repair and skin regeneration, in some major processes, via improvement of cellular behaviors of fibroblasts in the diabetic microenvironment. The beneficial advantages of mesenchymal stem cells-conditioned media on fibroblast cellular behaviors and wound healing may lead to establish a novel approach as an alternative therapeutic procedure to cure chronic wounds in diabetic conditions.

Impact of Photobiomodulation and Condition Medium on Mast Cell Counts, Degranulation, and Wound Strength in Infected Skin Wound Healing of Diabetic Rats.

Background: Numerous people suffer from diabetes mellitus (DM) and resultant diabetic foot ulcers (DFU), which lack effective treatment. Photobiomodulation (PBM) has accelerated wound healing in diabetic animals and patients in some studies. However, there is scant information on the number and activation state of skin mast cells (MCs) in PBM-treated diabetic wounds. Objective: We intend to assess the influence of the number of MCs and degranulation in the remodeling step of an infected wound model on wound strength and its microbial flora in a type 1 DM (T1DM) rat model by administration of PBM, condition medium (CM) derived from human bone marrow mesenchymal stem cells (hBMMSCs), and the combination of PBM+CM. Methods: We prepared CM by culturing hBMMSCs. T1DM was induced in 72 rats and, after 1 month, we created one excisional wound in each rat. All wounds were infected with methicillin-resistant Staphylococcus aureus (MRSA). We divided the rats into four groups: (n = 18): (i) control; (ii) PBM; (iii) CM, and (iv) PBM+CM. On days 4, 7, and 15, we conducted microbiological, tensiometrical, and stereological analyses. The type of MCs (T1MCs, T2MCs, or T3MCs) and total number of MCs (TOMCs) were counted by light microscopy. Results: On day 15, the PBM+CM, PBM, and CM groups had significantly increased wound strength compared with the control group. There was a significant decrease in colony-forming units (CFU) at all time points in the PBM+CM and PBM groups. The PBM+CM and PBM groups had more stable MCs (T1MCs), less significant degranulated MCs (T2MCs), less significant disintegrated MCs (T3MCs), and less significant TOMCs compared with the control group at all time points. Conclusions: PBM+CM and PBM treatments significantly increased the healing process in an ischemic and MRSA-infected wound model of T1DM rats. PBM+CM and PBM significantly decreased both TOMCs and their degranulation, and significantly decreased CFU.

Underwater-adhesive microparticle dressing composed of hydrophobically-modified Alaska pollock gelatin for gastrointestinal tract wound healing

Despite the success of minimally-invasive endoscopic submucosal dissection (ESD) for the treatment of early gastrointestinal cancer, additional symptoms after ESD, including contracture, perforation, bleeding, and esophageal stricture remain. Conventional wound dressings were ineffective in preventing stricture because of poor stability of underwater-adhesives on living tissues. Here, we present a microparticle-based wound dressing with underwater adhesive stability for the treatment of gastrointestinal tract wound healing after ESD. Monodisperse microparticles composed of hydrophobically-modified Alaska pollock gelatin were prepared by self-assembly of gelatin in water-ethanol mixed solvents and thermal crosslinking. Hydrophobic modification of gelatin with aliphatic aldehydes increased adhesion strength to gastric and esophageal submucosal tissues through hydrophobic interaction with living tissues and cohesion force. Optimal hydrophobic modification drastically improved underwater stability of microparticles compared to that of non-modified gelatin and formed a thick, integrated hydrogel layer on tissues. Histological observation of rat skin wound healing models showed that hydrophobically-modified gelatin microparticles decreased the expression levels of α-smooth muscle actin in the dermis layer and could suppress fibrosis and inflammation after ESD. The microparticle wound dressing with high underwater-adhesive stability has enormous therapeutic potential to promote wound healing in the gastrointestinal tract and prevent additional symptoms after ESD. Statement of SignificanceThe goal of this study was to develop wound dressing with strong tissue-adhesive property to living tissues for promoting wound healing after ESD treatment. Monodisperse microparticles composed of hydrophobically-modified Alaska pollock gelatin were prepared by self-assembly of gelatin in water-ethanol mixed solvents and thermal crosslinking. Hydrophobic modification of gelatin with aliphatic aldehydes enhanced adhesion strength to gastric and esophageal submucosal tissues through hydrophobic interaction with living tissues and cohesion force. Optimal hydrophobic modification drastically improved underwater stability of microparticles. The in vivo studies were performed to evaluate the ability of this colloidal wound dressing to suppress fibrosis. This new biomaterial has enormous potential to promote wound healing after ESD.

Adipose tissue-derived mesenchymal stem cells and keratinocytes co-culture on gelatin/chitosan/β-glycerol phosphate nanoscaffold in skin regeneration.

Using cell-based engineered skin is an emerging strategy for treating difficult-to-heal wounds. To date, much endeavor has been devoted to the fabrication of appropriate scaffolds with suitable biomechanical properties to support cell viability and growth in the microenvironment of a wound. The aim of this research was to assess the impact of adipose tissue-derived mesenchymal stem cells (AD-MSCs) and keratinocytes on gelatin/chitosan/β-glycerol phosphate (GCGP) nanoscaffold in full-thickness excisional skin wound healing of rats. For this purpose, AD-MSCs and keratinocytes were isolated from rats and GCGP nanoscaffolds were electrospun. Through an in vivo study, the percentage of wound closure was assessed on days 7, 14, and 21 after wound induction. Samples were taken from the wound sites in order to evaluate the density of collagen fibers and vessels at 7 and 14 days. Moreover, sampling was done on days 7 and 14 from wound sites to assess the density of collagen fibers and vessels. The wound closure rate was significantly increased in the keratinocytes-AD-MSCs-scaffold (KMS) group compared with other groups. The expressions of vascular endothelial growth factor, collagen type 1, and CD34 were also significantly higher in the KMS group compared with the other groups. These results suggest that the combination of AD-MSCs and keratinocytes seeded onto GCGP nanoscaffold provides a promising treatment for wound healing.

Human keratinocyte-derived microvesicle miRNA-21 promotes skin wound healing in diabetic rats through facilitating fibroblast function and angiogenesis.

Skin wound healing is a complex physiological process that maintains the integrity of the skin tissues, involving a variety of distinct cell types and signaling molecules. The specific signaling pathways or extracellular cues that govern the healing processes remain elusive. Microvesicles (MVs) have recently emerged as critical mediators of cell communication by delivery of genetic materials to target cells. In this study, we found the direct delivery of HEKa-MVs expressing miR-21 mimics significantly promoted the healing of skin wound in diabetic rats. In-depth studies showed that MV miR-21 promoted fibroblast migration, differentiation, and contraction, induced a pro-angiogenic process of endothelial cells and mediated a pro-inflammatory response. Mechanically, MV miR-21 might target specific essential effector mRNA in fibroblasts such as MMP-1, MMP-3, TIMP3, and TIMP4 to increase MMPs expression and enzymatic activities. Moreover, MV miR-21 regulated ɑ-SMA and N-cadherin to induce fibroblast-myofibroblast differentiation. MV miR-21 up-regulated the IL-6 and IL-8 expressions and their secretion to amplify the immune response. Furthermore, MV miR-21 down-regulated PTEN and RECK in protein level, and activate MAPK/ERK signaling cascade, thereby promoting fibroblast functions. Thus, our study has provided for the first time the basis for the potential application of HEKa-MVs, and MV miR-21 in particular for wound healing.

Moxibustion promoted transformation of inflammatory phase to facilitate wound healing in rats with full-thickness cutaneous wounds

Our previous study demonstrated that moxibustion could promote skin wound healing in rats with full-thickness cutaneous wounds. The present study was designed to observe the effect of moxibustion on the levels of pro-inflammatory and anti-inflammatory cytokines, and proliferation of vascular endothelial cells, so as to explore its mechanisms underlying facilitating wound-healing. A total of 84 adult SD male rats were randomly assigned to normal (n＝6), model(n＝39)and moxibustion(n＝39)groups. The skin wound model was established by removal of a piece of full-thickness skin from the median line of the rats' back (about 2 cm below the shoulder blade). Moxibustion was applied to the surrounding area of the focus for 25 min, once daily for 6 days. The blood samples were collected at day 1, 2, 3 and 5 after modeling for assaying serum contents of IL-1α， IL-1β， IL-6, IL-4, IL-10, IL-13, granulocyte-colony stimulating factor (G-CSF), granulocyte macrophagecolony stimulating factor (GM-CSF, an inflammatory mediator), macrophage inhibitory protein-1α (MIP-1α) and vascular endothelial growth factor (VEGF) with liquid chip methods, and the topical wound tissues were collected after trans-cardiac perfusion with 4% paraforma-ldehyde solution for detecting the expression of CD31 proteins by using immunofluorescence staining. After modeling and in comparison with the model group, the contents of serum IL-1α and IL-6 at the 1st day were significantly increased (P<0.05), but notably decreased at the 3rd day after modeling in the moxibustion group (P<0.05). The contents of serum IL-1β on day 1 and 2 were significantly higher in the moxibustion group than those of the model group (P<0.05). After moxibustion, the contents of serum IL-4 and IL-10 were significantly up-regulated on day 1 after modeling (P<0.05), and obviously down-regulated from the 3rd day on (P<0.05). The contents of serum MIP-1α on the 2nd day and serum VEGF on day 1 and 2, and wound-skin VEGF on day 5 were obviously up-regulated in the moxibustion group in comparison with the model group (P<0.05, P<0.01)．. Moxibustion promotes the inflammatory response by regulating the levels of both pro-inflammatory and anti-inflammatory cytokines in the early phase of skin wounds in rats, which may be in favor of the transformation from the inflammatory phase to the proliferation phase in advance, promoting wound healing at last.

Effect of Honey/PVA Hydrogel Loaded by Erythromycin on Full-Thickness Skin Wound Healing in Rats; Stereological Study.

Background: Skin wounds are a significant public health risk, and treatment of wound remains a challenging clinical problem for medical teams and researchers. Materials and Methods: In the present study, we aimed to investigate the healing effects of honey/polyvinyl alcohol (PVA) hydrogel loaded with erythromycin as wound dressing on skin wounds in rats, based on histological studies. In this study, 60 male Wistar rats, with a 1.5 ×1.5 cm2 diameter full-thickness wounds on the backs were divided into four groups: honey/PVA with the erythromycin hydrogel group, honey group, PVA group, and the control group, with no treatment. Skin biopsies were prepared at days 4, 7, and 14 for microscopic analyses. The stereological analysis, including the mean area of the wound, length of vessels, numerical density of fibroblast, macrophage, basal cell and volume of the epidermis, dermis, and fibrous tissue were performed. Results: Wounds area in the honey/PVA hydrogel with the erythromycin group were significantly (P<0.05) smaller than in the other group. The numerical density of fibroblast, macrophage, basal cell and volume of the epidermis in the honey/PVA hydrogel with the erythromycin group were significantly higher than other groups. Conclusion: According to our results, honey/PVA hydrogel with erythromycin may promote early wound healing and has a positive influence on fibroblast proliferation and re-epithelialization, and its administration is recommended after further validation of clinical data.

Is it possible to combine photodynamic therapy and application of dinitrosyl iron complexes in the wound treatment?

We have studied the effect of interactions between dinitrosyl iron complexes with thiol-containing ligands (DNIC-TL) and diglucamine salt of chlorine e6 (photoditazine, PD) on the rate of photosensitized oxidation of a model organic substrate – tryptophan – in the presence and absence of an amphiphilic polymer, Pluronic F127, as well as on the DNIC-TL and PD photostability. Using EPR and UV spectroscopy, we determined the rate constants for photodegradation of mono- and dinuclear DNIC-TL and PD, respectively. The presence of the photosensitizer and Pluronic F127 has been shown to have a negligible effect on the rate of photodestruction of mono- and dinuclear DNIC-TL, taking into account the changing DNIC-TL and PD concentrations in the photoexcitation conditions. At the same time, in the DNIC-TL presence, the rate of PD photodestruction increases, however, addition of Pluronic F127 leads to a decrease in the rate constant of PD photodestruction. The latter circumstance creates an opportunity for a simultaneous application of DNIC-TL and photodynamic therapy in the wound treatment without losing the PDT efficiency. Indeed, photodynamic therapy in combination with DNIC-TL facilitated skin wound healing in laboratory rats. As shown by a morphological study, application of the DNIC-TL-PD-F127 complex with the subsequent photoactivation was beneficial in reducing inflammation and stimulating regenerative processes.

Beneficial effect of Curcumin Nanoparticles-Hydrogel on excisional skin wound healing in type-I diabetic rat: Histological and immunohistochemical studies

Management of diabetic wounds remains a major challenge in the medical field, mostly due to incompetent outcomes of treatments. Curcumin has been documented as anti-inflammatory, antioxidant, antimicrobial and antineoplastic agent in addition to wound healing activities. However, its poor aqueous solubility and impaired skin permeation handicap its topical pharmaceutical usage. Hydrogel loaded curcumin nanoparticle (Cur-NP/HG) could overcome this pitfall and enable extended topical delivery of curcumin. Rat model of diabetes mellitus (DM) type I was induced using single injection of 70mg/kg streptozotocin (STZ) followed by full thickness skin wound. Rats were divided into 4 groups. GpI: control non-diabetic, GpII: diabetic non-treated, GpIII: diabetic treated with topical curcumin hydrogel (Cur/HG) and GpIV: diabetic treated with topical Cur-NP/HG. Histological assessment of epidermal regeneration, dermo-epidermal junction, leukocyte infiltration and collagen deposition, in addition to immunohistochemical staining for vascular endothelial growth factor (VEGF) and aquaporin-3 (AQP3) were performed. Diabetic rat possessed impaired wound closure, persistence of inflammation and decreased collagen deposition as compared to non-diabetic control. Application of Cur/HG induced partial improvement of the healing process in diabetic rats. Cur-NP/HG treatment provoked obvious improvement of the healing process with complete re-epithelization, intact dermo-epidermal junction, reorganization of the dermis with significantly increased collagen deposition and VEGF and AQP3 expression. These results illustrated that Cur-NP/HG have effectively improved the healing process in diabetic skin wound with substantial differences in the wound healing kinetics compared to wounds that received Cur/HG.

MDia1 and Cdc42 Regulate Activin B-Induced Migration of Bone Marrow-Derived Mesenchymal Stromal Cells.

In a previous study, we have shown that Activin B is a potent chemoattractant for bone marrow‐derived mesenchymal stromal cells (BMSCs). As such, the combination of Activin B and BMSCs significantly accelerated rat skin wound healing. In another study, we showed that RhoA activation plays a key role in Activin B‐induced BMSC migration. However, the role of the immediate downstream effectors of RhoA in this process is unclear. Here, we demonstrated that mammalian homolog of Drosophila diaphanous‐1 (mDia1), a downstream effector of RhoA, exerts a crucial function in Activin B‐induced BMSC migration by promoting membrane ruffling, microtubule morphology, and adhesion signaling dynamics. Furthermore, we showed that Activin B does not change Rac1 activity but increases Cdc42 activity in BMSCs. Inactivation of Cdc42 inhibited Activin B‐stimulated Golgi reorientation and the cell migration of BMSCs. Furthermore, knockdown of mDia1 affected Activin B‐induced BMSC‐mediated wound healing in vivo. In conclusion, this study demonstrated that the RhoA‐mDia1 and Cdc42 pathways regulate Activin B‐induced BMSC migration. This study may help to optimize clinical MSC‐based transplantation strategies to promote skin wound healing. stem cells 2019;37:150–161